Society of NeuroInterventional Surgery (SNIS): Annual Meeting

SAN DIEGO – The practice patterns for endovascular treatment of intracranial aneurysms appear to differ widely between sites inside and outside of North America, "likely reflecting practice variation rather than individual patient differences," according to Dr. Charles J. Prestigiacomo. "This is important to keep in mind when we’re establishing and designing multinational trials."

In terms of clinical outcomes, however, "everybody is doing very good work, no matter where you are in the world. I think that’s a testament to the technology and a testament to the physicians who are taking such good care of these patients," he said at the annual meeting of the Society of Neurointerventional Surgery.

Numerous international studies have shown that aneurysms can be safely and effectively treated via various coil types, "but we’ve had trouble trying to compare the efficacy of one international study with [that of] another, because there are differences in the primary end points of most of these studies," said Dr. Prestigiacomo, who chairs the department of neurological surgery at New Jersey Medical School, Newark. "The very low bleeding or rebleeding rates of treated aneurysms has led most investigators to use angiographic outcomes to compare devices. However, angiographic assessments are operator dependent and can potentially affect trial results."

In an effort to understand the impact of geography on aneurysm treatment, Dr. Prestigiacomo and his associates evaluated data from 626 patients who were enrolled in the MAPS (Matrix and Platinum Science) trial, a prospective, multicenter, multinational trial that compared bare platinum Guglielmi detachable coils and Matrix2 detachable coils, with the primary end point being target aneurysm recurrence. Patients were stratified into two groups: 407 who were treated at 28 North American (NA) sites, which included the United States, Canada, and Mexico, and 219 who were treated at 15 international (INTL) sites, which included South America, Europe, Asia, and the Asia-Pacific region. The researchers analyzed baseline patient demographics, comorbidities, and aneurysm characteristics, and compared procedural complications and clinical and angiographic outcomes between the two groups.

Several patient demographic factors differed significantly between the NA and INTL groups, including the proportion of female patients (76% vs. 60%, respectively), patients with ruptured aneurysms (28% vs. 52%), white patients (86% vs. 72%), and patients with two or more cardiovascular risk factors (31% vs. 15%), all with a P value less than .0001. NA patients were also more likely than their INTL counterparts to have a Hunt and Hess scale grade III or IV aneurysm (33% vs. 21%; P = .0452), to have more posterior-circulation aneurysms treated (16% vs. 8%; P = .0064), to have more aneurysms with a neck size of 4 mm or larger (39% vs. 31%; P = .0353), and to have more patients older than 55 years (54% vs. 40%; P = .0014).

The researchers found that a similar proportion of patients in the NA and INTL groups were alive and living independently at 1 year after the procedure (90% vs. 91% among those with ruptured aneurysms, respectively, and 95% vs. 97% among those with unruptured aneurysms), whereas a higher proportion of NA patients with ruptured aneurysms were discharged within 30 days, compared with their INTL counterparts (89% vs. 72%; P = .007). "I don’t think that is because of a clinical issue with the patients; it’s more of an issue of the health care system within the INTL community vs. the NA community," Dr. Prestigiacomo said.

Immediately post procedure, there was a lower incidence of complete or near complete occlusion in the NA group, compared with the INTL group (56% vs. 73%, respectively; P = .0002). The packing density of more than 25% was similar (43% vs. 39%) and the use of stents was more common in the NA group (45% vs. 19%; P less than .0001).

When the researchers evaluated 1-year angiographic outcomes, they noted no differences between the NA and INTL groups in the incidence of residual aneurysm (37% vs. 29%, respectively; P = .08) and retreatment rates for unruptured aneurysms (11% vs. 7%; P = .2285). But retreatment for ruptured aneurysms occurred significantly more often among those in the NA group than in the INTL group (22% vs. 4%; P = .001).

"When you look at when patients were treated, in North America there seems to be a higher probability of treating recurrent aneurysms within 1 year, and then the lines converge at 2 years," Dr. Prestigiacomo said. "In part, these differences may exist because there is a higher incidence of unruptured aneurysms in the North American population."

Dr. Prestigiacomo disclosed that he is a consultant for Stryker and Aesculap. He is also a member of the scientific advisory board for Thermopeutix and Edge Therapeutics, and is a board member of the International Brain Research Foundation.

SAN DIEGO – The practice patterns for endovascular treatment of intracranial aneurysms appear to differ widely between sites inside and outside of North America, "likely reflecting practice variation rather than individual patient differences," according to Dr. Charles J. Prestigiacomo. "This is important to keep in mind when we’re establishing and designing multinational trials."

In terms of clinical outcomes, however, "everybody is doing very good work, no matter where you are in the world. I think that’s a testament to the technology and a testament to the physicians who are taking such good care of these patients," he said at the annual meeting of the Society of Neurointerventional Surgery.

Numerous international studies have shown that aneurysms can be safely and effectively treated via various coil types, "but we’ve had trouble trying to compare the efficacy of one international study with [that of] another, because there are differences in the primary end points of most of these studies," said Dr. Prestigiacomo, who chairs the department of neurological surgery at New Jersey Medical School, Newark. "The very low bleeding or rebleeding rates of treated aneurysms has led most investigators to use angiographic outcomes to compare devices. However, angiographic assessments are operator dependent and can potentially affect trial results."

In an effort to understand the impact of geography on aneurysm treatment, Dr. Prestigiacomo and his associates evaluated data from 626 patients who were enrolled in the MAPS (Matrix and Platinum Science) trial, a prospective, multicenter, multinational trial that compared bare platinum Guglielmi detachable coils and Matrix2 detachable coils, with the primary end point being target aneurysm recurrence. Patients were stratified into two groups: 407 who were treated at 28 North American (NA) sites, which included the United States, Canada, and Mexico, and 219 who were treated at 15 international (INTL) sites, which included South America, Europe, Asia, and the Asia-Pacific region. The researchers analyzed baseline patient demographics, comorbidities, and aneurysm characteristics, and compared procedural complications and clinical and angiographic outcomes between the two groups.

Several patient demographic factors differed significantly between the NA and INTL groups, including the proportion of female patients (76% vs. 60%, respectively), patients with ruptured aneurysms (28% vs. 52%), white patients (86% vs. 72%), and patients with two or more cardiovascular risk factors (31% vs. 15%), all with a P value less than .0001. NA patients were also more likely than their INTL counterparts to have a Hunt and Hess scale grade III or IV aneurysm (33% vs. 21%; P = .0452), to have more posterior-circulation aneurysms treated (16% vs. 8%; P = .0064), to have more aneurysms with a neck size of 4 mm or larger (39% vs. 31%; P = .0353), and to have more patients older than 55 years (54% vs. 40%; P = .0014).

The researchers found that a similar proportion of patients in the NA and INTL groups were alive and living independently at 1 year after the procedure (90% vs. 91% among those with ruptured aneurysms, respectively, and 95% vs. 97% among those with unruptured aneurysms), whereas a higher proportion of NA patients with ruptured aneurysms were discharged within 30 days, compared with their INTL counterparts (89% vs. 72%; P = .007). "I don’t think that is because of a clinical issue with the patients; it’s more of an issue of the health care system within the INTL community vs. the NA community," Dr. Prestigiacomo said.

Immediately post procedure, there was a lower incidence of complete or near complete occlusion in the NA group, compared with the INTL group (56% vs. 73%, respectively; P = .0002). The packing density of more than 25% was similar (43% vs. 39%) and the use of stents was more common in the NA group (45% vs. 19%; P less than .0001).

When the researchers evaluated 1-year angiographic outcomes, they noted no differences between the NA and INTL groups in the incidence of residual aneurysm (37% vs. 29%, respectively; P = .08) and retreatment rates for unruptured aneurysms (11% vs. 7%; P = .2285). But retreatment for ruptured aneurysms occurred significantly more often among those in the NA group than in the INTL group (22% vs. 4%; P = .001).

"When you look at when patients were treated, in North America there seems to be a higher probability of treating recurrent aneurysms within 1 year, and then the lines converge at 2 years," Dr. Prestigiacomo said. "In part, these differences may exist because there is a higher incidence of unruptured aneurysms in the North American population."

Dr. Prestigiacomo disclosed that he is a consultant for Stryker and Aesculap. He is also a member of the scientific advisory board for Thermopeutix and Edge Therapeutics, and is a board member of the International Brain Research Foundation.

SAN DIEGO – The practice patterns for endovascular treatment of intracranial aneurysms appear to differ widely between sites inside and outside of North America, "likely reflecting practice variation rather than individual patient differences," according to Dr. Charles J. Prestigiacomo. "This is important to keep in mind when we’re establishing and designing multinational trials."

In terms of clinical outcomes, however, "everybody is doing very good work, no matter where you are in the world. I think that’s a testament to the technology and a testament to the physicians who are taking such good care of these patients," he said at the annual meeting of the Society of Neurointerventional Surgery.

Numerous international studies have shown that aneurysms can be safely and effectively treated via various coil types, "but we’ve had trouble trying to compare the efficacy of one international study with [that of] another, because there are differences in the primary end points of most of these studies," said Dr. Prestigiacomo, who chairs the department of neurological surgery at New Jersey Medical School, Newark. "The very low bleeding or rebleeding rates of treated aneurysms has led most investigators to use angiographic outcomes to compare devices. However, angiographic assessments are operator dependent and can potentially affect trial results."

In an effort to understand the impact of geography on aneurysm treatment, Dr. Prestigiacomo and his associates evaluated data from 626 patients who were enrolled in the MAPS (Matrix and Platinum Science) trial, a prospective, multicenter, multinational trial that compared bare platinum Guglielmi detachable coils and Matrix2 detachable coils, with the primary end point being target aneurysm recurrence. Patients were stratified into two groups: 407 who were treated at 28 North American (NA) sites, which included the United States, Canada, and Mexico, and 219 who were treated at 15 international (INTL) sites, which included South America, Europe, Asia, and the Asia-Pacific region. The researchers analyzed baseline patient demographics, comorbidities, and aneurysm characteristics, and compared procedural complications and clinical and angiographic outcomes between the two groups.

Several patient demographic factors differed significantly between the NA and INTL groups, including the proportion of female patients (76% vs. 60%, respectively), patients with ruptured aneurysms (28% vs. 52%), white patients (86% vs. 72%), and patients with two or more cardiovascular risk factors (31% vs. 15%), all with a P value less than .0001. NA patients were also more likely than their INTL counterparts to have a Hunt and Hess scale grade III or IV aneurysm (33% vs. 21%; P = .0452), to have more posterior-circulation aneurysms treated (16% vs. 8%; P = .0064), to have more aneurysms with a neck size of 4 mm or larger (39% vs. 31%; P = .0353), and to have more patients older than 55 years (54% vs. 40%; P = .0014).

The researchers found that a similar proportion of patients in the NA and INTL groups were alive and living independently at 1 year after the procedure (90% vs. 91% among those with ruptured aneurysms, respectively, and 95% vs. 97% among those with unruptured aneurysms), whereas a higher proportion of NA patients with ruptured aneurysms were discharged within 30 days, compared with their INTL counterparts (89% vs. 72%; P = .007). "I don’t think that is because of a clinical issue with the patients; it’s more of an issue of the health care system within the INTL community vs. the NA community," Dr. Prestigiacomo said.

Immediately post procedure, there was a lower incidence of complete or near complete occlusion in the NA group, compared with the INTL group (56% vs. 73%, respectively; P = .0002). The packing density of more than 25% was similar (43% vs. 39%) and the use of stents was more common in the NA group (45% vs. 19%; P less than .0001).

When the researchers evaluated 1-year angiographic outcomes, they noted no differences between the NA and INTL groups in the incidence of residual aneurysm (37% vs. 29%, respectively; P = .08) and retreatment rates for unruptured aneurysms (11% vs. 7%; P = .2285). But retreatment for ruptured aneurysms occurred significantly more often among those in the NA group than in the INTL group (22% vs. 4%; P = .001).

"When you look at when patients were treated, in North America there seems to be a higher probability of treating recurrent aneurysms within 1 year, and then the lines converge at 2 years," Dr. Prestigiacomo said. "In part, these differences may exist because there is a higher incidence of unruptured aneurysms in the North American population."

Dr. Prestigiacomo disclosed that he is a consultant for Stryker and Aesculap. He is also a member of the scientific advisory board for Thermopeutix and Edge Therapeutics, and is a board member of the International Brain Research Foundation.

SAN DIEGO – The 30-day periprocedural outcomes in patients who underwent carotid artery stenting with closed-cell design stents were not significantly inferior to outcomes of those treated with carotid endarterectomy, a large meta-analysis demonstrated.

However, patients who underwent carotid endarterectomy (CEA) had significantly better 30-day periprocedural outcomes, compared with those who underwent carotid artery stenting (CAS) with open-cell design stents.

Doug Brunk/IMNG Medical Media

"A number of randomized clinical trials and meta-analyses have consistently showed the higher risk of periprocedural stroke in patients undergoing stenting when compared to endarterectomy," Dr. Mohammed A. Almekhlafi said at the annual meeting of the Society of Neurointerventional Surgery. "One of the factors that has been implicated as a determinant of periprocedural neurological events is the stent cell design. The small free-cell area between the struts of a closed-cell stent theoretically provides better scaffolding of the vessel wall and superior plaque stabilization compared to the larger uncovered gaps in open-cell stents."

Dr. Almekhlafi, an interventional neurology fellow at the University of Calgary (Alta.), and his associates set out to investigate the impact of stent cell design on the outcome of randomized controlled trials comparing CAS vs. CEA. The stent cell design was divided into closed (meaning all stent struts are interconnected) or open (meaning not all stent-struts are interconnected). The primary outcome was a composite of the 30-day risk of stroke or death.

The final analysis included 4,949 patients from nine randomized clinical trials. Of these, 807 underwent CAS with closed-cell stenting, 1,657 underwent CAS with open-cell stenting, and 2,485 underwent CEA.

Dr. Almekhlafi reported that the primary outcome was significantly lower among patients in the CEA arm, compared with those in the CAS open-cell design arm (odds ratio, 1.84; P = .003). The primary outcome was lower among patients in the CEA arm, compared with those in the CAS closed-cell design arm, although this difference did not reach statistical significance (OR, 1.54; P = .29).

When the researchers limited their analysis to risk of 30-day periprocedural stroke, this outcome remained nonsignificant among patients in the CEA arm, compared with those in the CAS closed-cell design arm (OR 2.92; P = .22). However, the risk of 30-day periprocedural stroke remained significantly higher among patients in the CAS open-cell design arm, compared with those in the CEA arm (OR, 1.97; P = .0007).

"Uncertainty still exists regarding the impact of stent characteristics on CAS outcome," Dr. Almekhlafi said. "The size of the emboli might also be relevant."

He acknowledged certain limitations of the study, including the fact that trials included in this analysis did not randomize patients to open vs. closed stents, and that trials using the closed-design stents recruited fewer patients than did those using open-cell stents.

Dr. Almekhlafi said that he had no relevant financial disclosures to make.

SAN DIEGO – The 30-day periprocedural outcomes in patients who underwent carotid artery stenting with closed-cell design stents were not significantly inferior to outcomes of those treated with carotid endarterectomy, a large meta-analysis demonstrated.

However, patients who underwent carotid endarterectomy (CEA) had significantly better 30-day periprocedural outcomes, compared with those who underwent carotid artery stenting (CAS) with open-cell design stents.

Doug Brunk/IMNG Medical Media

"A number of randomized clinical trials and meta-analyses have consistently showed the higher risk of periprocedural stroke in patients undergoing stenting when compared to endarterectomy," Dr. Mohammed A. Almekhlafi said at the annual meeting of the Society of Neurointerventional Surgery. "One of the factors that has been implicated as a determinant of periprocedural neurological events is the stent cell design. The small free-cell area between the struts of a closed-cell stent theoretically provides better scaffolding of the vessel wall and superior plaque stabilization compared to the larger uncovered gaps in open-cell stents."

Dr. Almekhlafi, an interventional neurology fellow at the University of Calgary (Alta.), and his associates set out to investigate the impact of stent cell design on the outcome of randomized controlled trials comparing CAS vs. CEA. The stent cell design was divided into closed (meaning all stent struts are interconnected) or open (meaning not all stent-struts are interconnected). The primary outcome was a composite of the 30-day risk of stroke or death.

The final analysis included 4,949 patients from nine randomized clinical trials. Of these, 807 underwent CAS with closed-cell stenting, 1,657 underwent CAS with open-cell stenting, and 2,485 underwent CEA.

Dr. Almekhlafi reported that the primary outcome was significantly lower among patients in the CEA arm, compared with those in the CAS open-cell design arm (odds ratio, 1.84; P = .003). The primary outcome was lower among patients in the CEA arm, compared with those in the CAS closed-cell design arm, although this difference did not reach statistical significance (OR, 1.54; P = .29).

When the researchers limited their analysis to risk of 30-day periprocedural stroke, this outcome remained nonsignificant among patients in the CEA arm, compared with those in the CAS closed-cell design arm (OR 2.92; P = .22). However, the risk of 30-day periprocedural stroke remained significantly higher among patients in the CAS open-cell design arm, compared with those in the CEA arm (OR, 1.97; P = .0007).

"Uncertainty still exists regarding the impact of stent characteristics on CAS outcome," Dr. Almekhlafi said. "The size of the emboli might also be relevant."

He acknowledged certain limitations of the study, including the fact that trials included in this analysis did not randomize patients to open vs. closed stents, and that trials using the closed-design stents recruited fewer patients than did those using open-cell stents.

Dr. Almekhlafi said that he had no relevant financial disclosures to make.

SAN DIEGO – The 30-day periprocedural outcomes in patients who underwent carotid artery stenting with closed-cell design stents were not significantly inferior to outcomes of those treated with carotid endarterectomy, a large meta-analysis demonstrated.

However, patients who underwent carotid endarterectomy (CEA) had significantly better 30-day periprocedural outcomes, compared with those who underwent carotid artery stenting (CAS) with open-cell design stents.

Doug Brunk/IMNG Medical Media

"A number of randomized clinical trials and meta-analyses have consistently showed the higher risk of periprocedural stroke in patients undergoing stenting when compared to endarterectomy," Dr. Mohammed A. Almekhlafi said at the annual meeting of the Society of Neurointerventional Surgery. "One of the factors that has been implicated as a determinant of periprocedural neurological events is the stent cell design. The small free-cell area between the struts of a closed-cell stent theoretically provides better scaffolding of the vessel wall and superior plaque stabilization compared to the larger uncovered gaps in open-cell stents."

Dr. Almekhlafi, an interventional neurology fellow at the University of Calgary (Alta.), and his associates set out to investigate the impact of stent cell design on the outcome of randomized controlled trials comparing CAS vs. CEA. The stent cell design was divided into closed (meaning all stent struts are interconnected) or open (meaning not all stent-struts are interconnected). The primary outcome was a composite of the 30-day risk of stroke or death.

The final analysis included 4,949 patients from nine randomized clinical trials. Of these, 807 underwent CAS with closed-cell stenting, 1,657 underwent CAS with open-cell stenting, and 2,485 underwent CEA.

Dr. Almekhlafi reported that the primary outcome was significantly lower among patients in the CEA arm, compared with those in the CAS open-cell design arm (odds ratio, 1.84; P = .003). The primary outcome was lower among patients in the CEA arm, compared with those in the CAS closed-cell design arm, although this difference did not reach statistical significance (OR, 1.54; P = .29).

When the researchers limited their analysis to risk of 30-day periprocedural stroke, this outcome remained nonsignificant among patients in the CEA arm, compared with those in the CAS closed-cell design arm (OR 2.92; P = .22). However, the risk of 30-day periprocedural stroke remained significantly higher among patients in the CAS open-cell design arm, compared with those in the CEA arm (OR, 1.97; P = .0007).

"Uncertainty still exists regarding the impact of stent characteristics on CAS outcome," Dr. Almekhlafi said. "The size of the emboli might also be relevant."

He acknowledged certain limitations of the study, including the fact that trials included in this analysis did not randomize patients to open vs. closed stents, and that trials using the closed-design stents recruited fewer patients than did those using open-cell stents.

Dr. Almekhlafi said that he had no relevant financial disclosures to make.

SAN DIEGO – A surgical procedure or intervention with a perioperative stroke risk of less than 9% would advance the treatment of chronic carotid artery occlusive disease, according to Dr. Colin P. Derdeyn.

If such a procedure existed, "we’d have an intervention that would provide a benefit in a very high-risk population," he said at the annual meeting of the Society of Neurointerventional Surgery.

The Carotid Occlusion Surgery Study, a recently completed randomized trial of surgical bypass for complete atherosclerotic carotid artery occlusion, failed to show a benefit for surgery. The risk of stroke in patients who had surgery, but did not suffer a complication from the surgery, was much lower than the risk of stroke in the medically treated patients. If the perioperative complication rate had been less than 9%, surgery might have shown a benefit in the trial, explained Dr. Derdeyn, director of the stroke and cerebrovascular center and professor of radiology, neurology, and neurologic surgery at Washington University, St. Louis.

Dr. Derdeyn and his colleagues are trying to take the perioperative complication rate of endovascular recanalization below 9% by organizing a pilot trial of its use in patients with subacute or chronic carotid occlusion. PET scans will be used "to identify patients whom we know are going to have a high 2-year risk of stroke, and examine safety and 2-year stroke rates," he said. "There have been a number of case series, primarily from Asia, with very high recanalization rates and very low perioperative complication rates for going through a chronic occlusion and stenting it open."

Another important area for future research in chronic occlusive disease may involve exploration of a theory known as reversible cognitive impairment. "The idea here is that there is a metabolic downregulation secondary to chronic oligemia, and that this reduced metabolic activity reduces the blood flow needs," Dr. Derdeyn said. "The second part of this theory is that there is cognitive impairment related to this metabolic downregulation, and the third part of the theory is that if you revascularize, it all gets better."

He emphasized that reversible cognitive impairment has not been proven. "We’ve certainly had anecdotal cases that make us think that it’s true, but we have no proof yet that this exists," he said. "There have been a lot of case series, but the problem is that many of them include stroke patients who recovered from their strokes. We expect stroke patients to get better in terms of their neurocognition, so there is no good control [group]."

Dr. Derdeyn is one of the investigators in the National Institute of Neurological Disorders and Stroke–sponsored Randomized Evaluation Carotid Occlusion and Neurocognition (RECON) trial. For this blinded clinical study, researchers set out to test the hypothesis that patients who have symptomatic, unilateral carotid artery occlusion and increased oxygen extraction fraction will have better cognitive function following extracranial to intracranial bypass, compared with an identical group of patients treated with best medical therapy alone. The results of the trial are expected to be presented at the 2013 International Stroke Conference.

Baseline data from RECON published earlier this year demonstrated an association of increased oxygen extraction fraction with cognitive impairment in 44 patients who suffered a transient ischemic attack (Neurology 2012;78:250-5).

Dr. Derdeyn said that he had no relevant financial disclosures.

SAN DIEGO – A surgical procedure or intervention with a perioperative stroke risk of less than 9% would advance the treatment of chronic carotid artery occlusive disease, according to Dr. Colin P. Derdeyn.

If such a procedure existed, "we’d have an intervention that would provide a benefit in a very high-risk population," he said at the annual meeting of the Society of Neurointerventional Surgery.

The Carotid Occlusion Surgery Study, a recently completed randomized trial of surgical bypass for complete atherosclerotic carotid artery occlusion, failed to show a benefit for surgery. The risk of stroke in patients who had surgery, but did not suffer a complication from the surgery, was much lower than the risk of stroke in the medically treated patients. If the perioperative complication rate had been less than 9%, surgery might have shown a benefit in the trial, explained Dr. Derdeyn, director of the stroke and cerebrovascular center and professor of radiology, neurology, and neurologic surgery at Washington University, St. Louis.

Dr. Derdeyn and his colleagues are trying to take the perioperative complication rate of endovascular recanalization below 9% by organizing a pilot trial of its use in patients with subacute or chronic carotid occlusion. PET scans will be used "to identify patients whom we know are going to have a high 2-year risk of stroke, and examine safety and 2-year stroke rates," he said. "There have been a number of case series, primarily from Asia, with very high recanalization rates and very low perioperative complication rates for going through a chronic occlusion and stenting it open."

Another important area for future research in chronic occlusive disease may involve exploration of a theory known as reversible cognitive impairment. "The idea here is that there is a metabolic downregulation secondary to chronic oligemia, and that this reduced metabolic activity reduces the blood flow needs," Dr. Derdeyn said. "The second part of this theory is that there is cognitive impairment related to this metabolic downregulation, and the third part of the theory is that if you revascularize, it all gets better."

He emphasized that reversible cognitive impairment has not been proven. "We’ve certainly had anecdotal cases that make us think that it’s true, but we have no proof yet that this exists," he said. "There have been a lot of case series, but the problem is that many of them include stroke patients who recovered from their strokes. We expect stroke patients to get better in terms of their neurocognition, so there is no good control [group]."

Dr. Derdeyn is one of the investigators in the National Institute of Neurological Disorders and Stroke–sponsored Randomized Evaluation Carotid Occlusion and Neurocognition (RECON) trial. For this blinded clinical study, researchers set out to test the hypothesis that patients who have symptomatic, unilateral carotid artery occlusion and increased oxygen extraction fraction will have better cognitive function following extracranial to intracranial bypass, compared with an identical group of patients treated with best medical therapy alone. The results of the trial are expected to be presented at the 2013 International Stroke Conference.

Baseline data from RECON published earlier this year demonstrated an association of increased oxygen extraction fraction with cognitive impairment in 44 patients who suffered a transient ischemic attack (Neurology 2012;78:250-5).

Dr. Derdeyn said that he had no relevant financial disclosures.

SAN DIEGO – A surgical procedure or intervention with a perioperative stroke risk of less than 9% would advance the treatment of chronic carotid artery occlusive disease, according to Dr. Colin P. Derdeyn.

If such a procedure existed, "we’d have an intervention that would provide a benefit in a very high-risk population," he said at the annual meeting of the Society of Neurointerventional Surgery.

The Carotid Occlusion Surgery Study, a recently completed randomized trial of surgical bypass for complete atherosclerotic carotid artery occlusion, failed to show a benefit for surgery. The risk of stroke in patients who had surgery, but did not suffer a complication from the surgery, was much lower than the risk of stroke in the medically treated patients. If the perioperative complication rate had been less than 9%, surgery might have shown a benefit in the trial, explained Dr. Derdeyn, director of the stroke and cerebrovascular center and professor of radiology, neurology, and neurologic surgery at Washington University, St. Louis.

Dr. Derdeyn and his colleagues are trying to take the perioperative complication rate of endovascular recanalization below 9% by organizing a pilot trial of its use in patients with subacute or chronic carotid occlusion. PET scans will be used "to identify patients whom we know are going to have a high 2-year risk of stroke, and examine safety and 2-year stroke rates," he said. "There have been a number of case series, primarily from Asia, with very high recanalization rates and very low perioperative complication rates for going through a chronic occlusion and stenting it open."

Another important area for future research in chronic occlusive disease may involve exploration of a theory known as reversible cognitive impairment. "The idea here is that there is a metabolic downregulation secondary to chronic oligemia, and that this reduced metabolic activity reduces the blood flow needs," Dr. Derdeyn said. "The second part of this theory is that there is cognitive impairment related to this metabolic downregulation, and the third part of the theory is that if you revascularize, it all gets better."

He emphasized that reversible cognitive impairment has not been proven. "We’ve certainly had anecdotal cases that make us think that it’s true, but we have no proof yet that this exists," he said. "There have been a lot of case series, but the problem is that many of them include stroke patients who recovered from their strokes. We expect stroke patients to get better in terms of their neurocognition, so there is no good control [group]."

Dr. Derdeyn is one of the investigators in the National Institute of Neurological Disorders and Stroke–sponsored Randomized Evaluation Carotid Occlusion and Neurocognition (RECON) trial. For this blinded clinical study, researchers set out to test the hypothesis that patients who have symptomatic, unilateral carotid artery occlusion and increased oxygen extraction fraction will have better cognitive function following extracranial to intracranial bypass, compared with an identical group of patients treated with best medical therapy alone. The results of the trial are expected to be presented at the 2013 International Stroke Conference.

Baseline data from RECON published earlier this year demonstrated an association of increased oxygen extraction fraction with cognitive impairment in 44 patients who suffered a transient ischemic attack (Neurology 2012;78:250-5).

Dr. Derdeyn said that he had no relevant financial disclosures.

SAN DIEGO – Sometimes the only relief for a patient who presents with chronic and recalcitrant pain comes from a course of spinal cord stimulation.

"I consider spinal cord stimulation a real home run," Dr. Allan L. Brook said at the annual meeting of the Society of Neurointerventional Surgery. "You can really help patients who have no other method of pain relief."

Spinal cord stimulation is a form of neuromodulation that masks the pain signals by delivering pulses of electricity via an electrode directly to the spinal cord, leading to parasthesias along the desired path. The procedure has Food and Drug Administration clearance for treating neuropathic, intractable pain in the extremities and trunk.

In describing its proposed mechanism of action, Dr. Brook, director of neurointerventional neuroradiology at Montefiore Medical Center in the Bronx, N.Y., said that the noxious afferent stimulus is masked by nonnoxious sensations produced by stimulation. This results in a conductance blockade of the spinothalamic sensory system, which in turn activates supraspinal pain-relieving centers. Stimulation also causes blockage of supraspinal or segmental autonomic nervous systems, and alters the way neurotransmitters are released.

"I consider spinal cord stimulation a real home run."

The most common indication for spinal cord stimulation is failed back surgery syndromes. "There are many fusion surgeries out there with poor results," said Dr. Brook, who is also professor of clinical radiology and neurosurgery at Albert Einstein College of Medicine, New York. "Causes may include arachnoiditis, recurrent or residual disk herniation, epidural fibrosis, and radiculopathy from any cause."

Other indications include complex regional pain syndrome type I, CRPS type II, ischemic limb pain, refractory angina, peripheral neuropathy, abdominal pain, brachial plexus/cervical pain, interstitial cystitis, phantom limb pain, postherpetic neuralgia, headache/facial pain, and chronic pain that fails medical therapy.

Contraindications for spinal cord stimulation include patients with an infection, those in whom standard pain therapy works, those with coagulation issues, those who are mentally incompetent, and those who lack health insurance, as each device costs about $20,000. Psychological exclusion criteria include patients with active psychosis or those who are suicidal, and those with major depression, mood problems, or substance abuse problems. "Insurance companies require a psychological evaluation for this procedure," Dr. Brook said.

Orientation of the pain drives placement of the stimulator’s lead tip. For example, the lead tip is positioned on C2-C5 for pain in the upper extremity, on T11-L1 for foot pain, on T9-T10 for lower extremity pain, on T8-T10 for low back pain, on T1-T2 for chest pain, on C1-C2 for occipital neuralgia, and on S2-S4 for pelvic pain.

The least invasive initial approach is to temporarily position the spinal cord stimulator for several days so that the proximal lead portion is secured to skin. If the pain relief exceeds 50% during this trial period, then a permanent spine stimulator can be placed surgically.

The main drawback to permanent placement is that patients can’t undergo an MRI, but Dr. Brook said that an MRI-compatible device is currently being developed. Complications can rarely occur, including nerve injury, epidural hematoma, wound infection, and lead migration. "All of these can be prevented with good techniques," he said.

Researchers who conducted a 20-year retrospective review of 51 studies of spinal cord stimulation concluded that the procedure had a positive effect on chronic low back pain, severe limb ischemia, refractory angina, and peripheral neuropathy (J. Neurosurg. 2004;100:254-67).

A randomized, prospective, controlled trial of spinal cord stimulation in patients who had reflex sympathetic dystrophy (now called CRPS type I) for at least 6 months found a significant benefit of decreased pain and improved function, with a P value less than .001 (N. Engl. J. Med. 2000;343:618-24).

Another trial found that neurostimulation for failed back surgery syndrome resulted in a cost savings after 2.5 years, compared with conventional medical management (Neurosurgery 2002;51:106-16).

"This is a reversible, minimally invasive procedure," Dr. Brook said of spinal cord stimulation. "It’s nondestructive, compared with neuroablation; it reduces the abuse of narcotics; and it can improve a patient’s ability to perform activities of daily living."

Dr. Brook said that he had no relevant financial conflicts to disclose.

SAN DIEGO – Sometimes the only relief for a patient who presents with chronic and recalcitrant pain comes from a course of spinal cord stimulation.

"I consider spinal cord stimulation a real home run," Dr. Allan L. Brook said at the annual meeting of the Society of Neurointerventional Surgery. "You can really help patients who have no other method of pain relief."

Spinal cord stimulation is a form of neuromodulation that masks the pain signals by delivering pulses of electricity via an electrode directly to the spinal cord, leading to parasthesias along the desired path. The procedure has Food and Drug Administration clearance for treating neuropathic, intractable pain in the extremities and trunk.

In describing its proposed mechanism of action, Dr. Brook, director of neurointerventional neuroradiology at Montefiore Medical Center in the Bronx, N.Y., said that the noxious afferent stimulus is masked by nonnoxious sensations produced by stimulation. This results in a conductance blockade of the spinothalamic sensory system, which in turn activates supraspinal pain-relieving centers. Stimulation also causes blockage of supraspinal or segmental autonomic nervous systems, and alters the way neurotransmitters are released.

"I consider spinal cord stimulation a real home run."

The most common indication for spinal cord stimulation is failed back surgery syndromes. "There are many fusion surgeries out there with poor results," said Dr. Brook, who is also professor of clinical radiology and neurosurgery at Albert Einstein College of Medicine, New York. "Causes may include arachnoiditis, recurrent or residual disk herniation, epidural fibrosis, and radiculopathy from any cause."

Other indications include complex regional pain syndrome type I, CRPS type II, ischemic limb pain, refractory angina, peripheral neuropathy, abdominal pain, brachial plexus/cervical pain, interstitial cystitis, phantom limb pain, postherpetic neuralgia, headache/facial pain, and chronic pain that fails medical therapy.

Contraindications for spinal cord stimulation include patients with an infection, those in whom standard pain therapy works, those with coagulation issues, those who are mentally incompetent, and those who lack health insurance, as each device costs about $20,000. Psychological exclusion criteria include patients with active psychosis or those who are suicidal, and those with major depression, mood problems, or substance abuse problems. "Insurance companies require a psychological evaluation for this procedure," Dr. Brook said.

Orientation of the pain drives placement of the stimulator’s lead tip. For example, the lead tip is positioned on C2-C5 for pain in the upper extremity, on T11-L1 for foot pain, on T9-T10 for lower extremity pain, on T8-T10 for low back pain, on T1-T2 for chest pain, on C1-C2 for occipital neuralgia, and on S2-S4 for pelvic pain.

The least invasive initial approach is to temporarily position the spinal cord stimulator for several days so that the proximal lead portion is secured to skin. If the pain relief exceeds 50% during this trial period, then a permanent spine stimulator can be placed surgically.

The main drawback to permanent placement is that patients can’t undergo an MRI, but Dr. Brook said that an MRI-compatible device is currently being developed. Complications can rarely occur, including nerve injury, epidural hematoma, wound infection, and lead migration. "All of these can be prevented with good techniques," he said.

Researchers who conducted a 20-year retrospective review of 51 studies of spinal cord stimulation concluded that the procedure had a positive effect on chronic low back pain, severe limb ischemia, refractory angina, and peripheral neuropathy (J. Neurosurg. 2004;100:254-67).

A randomized, prospective, controlled trial of spinal cord stimulation in patients who had reflex sympathetic dystrophy (now called CRPS type I) for at least 6 months found a significant benefit of decreased pain and improved function, with a P value less than .001 (N. Engl. J. Med. 2000;343:618-24).

Another trial found that neurostimulation for failed back surgery syndrome resulted in a cost savings after 2.5 years, compared with conventional medical management (Neurosurgery 2002;51:106-16).

"This is a reversible, minimally invasive procedure," Dr. Brook said of spinal cord stimulation. "It’s nondestructive, compared with neuroablation; it reduces the abuse of narcotics; and it can improve a patient’s ability to perform activities of daily living."

Dr. Brook said that he had no relevant financial conflicts to disclose.

SAN DIEGO – Sometimes the only relief for a patient who presents with chronic and recalcitrant pain comes from a course of spinal cord stimulation.

"I consider spinal cord stimulation a real home run," Dr. Allan L. Brook said at the annual meeting of the Society of Neurointerventional Surgery. "You can really help patients who have no other method of pain relief."

Spinal cord stimulation is a form of neuromodulation that masks the pain signals by delivering pulses of electricity via an electrode directly to the spinal cord, leading to parasthesias along the desired path. The procedure has Food and Drug Administration clearance for treating neuropathic, intractable pain in the extremities and trunk.

In describing its proposed mechanism of action, Dr. Brook, director of neurointerventional neuroradiology at Montefiore Medical Center in the Bronx, N.Y., said that the noxious afferent stimulus is masked by nonnoxious sensations produced by stimulation. This results in a conductance blockade of the spinothalamic sensory system, which in turn activates supraspinal pain-relieving centers. Stimulation also causes blockage of supraspinal or segmental autonomic nervous systems, and alters the way neurotransmitters are released.

"I consider spinal cord stimulation a real home run."

The most common indication for spinal cord stimulation is failed back surgery syndromes. "There are many fusion surgeries out there with poor results," said Dr. Brook, who is also professor of clinical radiology and neurosurgery at Albert Einstein College of Medicine, New York. "Causes may include arachnoiditis, recurrent or residual disk herniation, epidural fibrosis, and radiculopathy from any cause."

Other indications include complex regional pain syndrome type I, CRPS type II, ischemic limb pain, refractory angina, peripheral neuropathy, abdominal pain, brachial plexus/cervical pain, interstitial cystitis, phantom limb pain, postherpetic neuralgia, headache/facial pain, and chronic pain that fails medical therapy.

Contraindications for spinal cord stimulation include patients with an infection, those in whom standard pain therapy works, those with coagulation issues, those who are mentally incompetent, and those who lack health insurance, as each device costs about $20,000. Psychological exclusion criteria include patients with active psychosis or those who are suicidal, and those with major depression, mood problems, or substance abuse problems. "Insurance companies require a psychological evaluation for this procedure," Dr. Brook said.

Orientation of the pain drives placement of the stimulator’s lead tip. For example, the lead tip is positioned on C2-C5 for pain in the upper extremity, on T11-L1 for foot pain, on T9-T10 for lower extremity pain, on T8-T10 for low back pain, on T1-T2 for chest pain, on C1-C2 for occipital neuralgia, and on S2-S4 for pelvic pain.

The least invasive initial approach is to temporarily position the spinal cord stimulator for several days so that the proximal lead portion is secured to skin. If the pain relief exceeds 50% during this trial period, then a permanent spine stimulator can be placed surgically.

The main drawback to permanent placement is that patients can’t undergo an MRI, but Dr. Brook said that an MRI-compatible device is currently being developed. Complications can rarely occur, including nerve injury, epidural hematoma, wound infection, and lead migration. "All of these can be prevented with good techniques," he said.

Researchers who conducted a 20-year retrospective review of 51 studies of spinal cord stimulation concluded that the procedure had a positive effect on chronic low back pain, severe limb ischemia, refractory angina, and peripheral neuropathy (J. Neurosurg. 2004;100:254-67).

A randomized, prospective, controlled trial of spinal cord stimulation in patients who had reflex sympathetic dystrophy (now called CRPS type I) for at least 6 months found a significant benefit of decreased pain and improved function, with a P value less than .001 (N. Engl. J. Med. 2000;343:618-24).

Another trial found that neurostimulation for failed back surgery syndrome resulted in a cost savings after 2.5 years, compared with conventional medical management (Neurosurgery 2002;51:106-16).

"This is a reversible, minimally invasive procedure," Dr. Brook said of spinal cord stimulation. "It’s nondestructive, compared with neuroablation; it reduces the abuse of narcotics; and it can improve a patient’s ability to perform activities of daily living."

Dr. Brook said that he had no relevant financial conflicts to disclose.

SAN DIEGO – An approach that uses CT perfusion findings to select patients for mechanical thrombectomy resulted in effective, safe treatment of stroke patients beyond the traditional 7- to 8-hour treatment window, results from a single-center study demonstrated.

"CT perfusion–based patient selection for endovascular therapy enables us to treat patients who would otherwise have not received such therapy based on time criteria," Jordan Magarik said at the annual meeting of the Society of Neurointerventional Surgery. "We have seen improved outcomes over historical controls and improved safety as well. The bottom line is that patient selection is paramount. When patients are selected based solely on CT perfusion imaging, we are finding very similar rates of good functional outcome regardless of when they were treated, whether it’s 8 or 18 hours after symptom onset."

When the Medical University of South Carolina (MUSC) in Charleston launched its Comprehensive Stroke Center in 2008, clinicians there devised an alternate method of selecting patients solely based on the CT perfusion findings, regardless of their time from symptom onset. For the current study, Mr. Magarik, who is a medical student at MUSC, and his associates reviewed the records of 140 stroke patients who were treated at the stroke center from 2008 to 2011. The mean age of the patients was 67 years. Data of interest included age, concurrent administration of IV tissue plasminogen activator (TPA), time to treatment, presenting National Institutes of Health Stroke Scale (NIHSS) score, 90-day modified Rankin score (mRS), and angiographic recanalization rates. The primary intra-arterial device used was the Penumbra System.

All 140 patients underwent mechanical thrombectomy; 54 received IV TPA in addition to mechanical thrombectomy and 86 only underwent mechanical thrombectomy. The mean NIHSS score was 16.2, and the mean time to treatment was 11.3 hours, which is well beyond the traditional 7- to 8-hour time window used in mechanical device trials, said Mr. Magarik.

The majority of patients (87%) achieved a partial or full recanalization and 10% of patients suffered symptomatic intracranial hemorrhage, which is consistent with previous trials.

More than one-third of patients (38%) achieved a 90-day mRS of 0-2, and 53% achieved a 90-day mRS of 0-3. The mortality rate was 25%, which is consistent with previous trials.

When the researchers divided patients on the basis of mean time from symptom onset to treatment, they observed no statistically significant differences in the rates of patients with mRS of 0-2 (31% among those treated within a 7-hour window vs. 42% among those treated beyond a 7-hour window) or mRS of 0-3 (49% among those treated within a 7-hour window vs. 55% among those treated beyond a 7-hour window).

"Many patients in the later time group are presenting 15 or 18 hours out from symptom onset, yet they are still achieving a very similar rate of good functional outcome," Mr. Magarik said. "We believe this is because they were selected based on their CT perfusion findings."

Mr. Magarik said that he had no relevant financial disclosures to make.

SAN DIEGO – An approach that uses CT perfusion findings to select patients for mechanical thrombectomy resulted in effective, safe treatment of stroke patients beyond the traditional 7- to 8-hour treatment window, results from a single-center study demonstrated.

"CT perfusion–based patient selection for endovascular therapy enables us to treat patients who would otherwise have not received such therapy based on time criteria," Jordan Magarik said at the annual meeting of the Society of Neurointerventional Surgery. "We have seen improved outcomes over historical controls and improved safety as well. The bottom line is that patient selection is paramount. When patients are selected based solely on CT perfusion imaging, we are finding very similar rates of good functional outcome regardless of when they were treated, whether it’s 8 or 18 hours after symptom onset."

When the Medical University of South Carolina (MUSC) in Charleston launched its Comprehensive Stroke Center in 2008, clinicians there devised an alternate method of selecting patients solely based on the CT perfusion findings, regardless of their time from symptom onset. For the current study, Mr. Magarik, who is a medical student at MUSC, and his associates reviewed the records of 140 stroke patients who were treated at the stroke center from 2008 to 2011. The mean age of the patients was 67 years. Data of interest included age, concurrent administration of IV tissue plasminogen activator (TPA), time to treatment, presenting National Institutes of Health Stroke Scale (NIHSS) score, 90-day modified Rankin score (mRS), and angiographic recanalization rates. The primary intra-arterial device used was the Penumbra System.

All 140 patients underwent mechanical thrombectomy; 54 received IV TPA in addition to mechanical thrombectomy and 86 only underwent mechanical thrombectomy. The mean NIHSS score was 16.2, and the mean time to treatment was 11.3 hours, which is well beyond the traditional 7- to 8-hour time window used in mechanical device trials, said Mr. Magarik.

The majority of patients (87%) achieved a partial or full recanalization and 10% of patients suffered symptomatic intracranial hemorrhage, which is consistent with previous trials.

More than one-third of patients (38%) achieved a 90-day mRS of 0-2, and 53% achieved a 90-day mRS of 0-3. The mortality rate was 25%, which is consistent with previous trials.

When the researchers divided patients on the basis of mean time from symptom onset to treatment, they observed no statistically significant differences in the rates of patients with mRS of 0-2 (31% among those treated within a 7-hour window vs. 42% among those treated beyond a 7-hour window) or mRS of 0-3 (49% among those treated within a 7-hour window vs. 55% among those treated beyond a 7-hour window).

"Many patients in the later time group are presenting 15 or 18 hours out from symptom onset, yet they are still achieving a very similar rate of good functional outcome," Mr. Magarik said. "We believe this is because they were selected based on their CT perfusion findings."

Mr. Magarik said that he had no relevant financial disclosures to make.

SAN DIEGO – An approach that uses CT perfusion findings to select patients for mechanical thrombectomy resulted in effective, safe treatment of stroke patients beyond the traditional 7- to 8-hour treatment window, results from a single-center study demonstrated.

"CT perfusion–based patient selection for endovascular therapy enables us to treat patients who would otherwise have not received such therapy based on time criteria," Jordan Magarik said at the annual meeting of the Society of Neurointerventional Surgery. "We have seen improved outcomes over historical controls and improved safety as well. The bottom line is that patient selection is paramount. When patients are selected based solely on CT perfusion imaging, we are finding very similar rates of good functional outcome regardless of when they were treated, whether it’s 8 or 18 hours after symptom onset."

When the Medical University of South Carolina (MUSC) in Charleston launched its Comprehensive Stroke Center in 2008, clinicians there devised an alternate method of selecting patients solely based on the CT perfusion findings, regardless of their time from symptom onset. For the current study, Mr. Magarik, who is a medical student at MUSC, and his associates reviewed the records of 140 stroke patients who were treated at the stroke center from 2008 to 2011. The mean age of the patients was 67 years. Data of interest included age, concurrent administration of IV tissue plasminogen activator (TPA), time to treatment, presenting National Institutes of Health Stroke Scale (NIHSS) score, 90-day modified Rankin score (mRS), and angiographic recanalization rates. The primary intra-arterial device used was the Penumbra System.

All 140 patients underwent mechanical thrombectomy; 54 received IV TPA in addition to mechanical thrombectomy and 86 only underwent mechanical thrombectomy. The mean NIHSS score was 16.2, and the mean time to treatment was 11.3 hours, which is well beyond the traditional 7- to 8-hour time window used in mechanical device trials, said Mr. Magarik.

The majority of patients (87%) achieved a partial or full recanalization and 10% of patients suffered symptomatic intracranial hemorrhage, which is consistent with previous trials.

More than one-third of patients (38%) achieved a 90-day mRS of 0-2, and 53% achieved a 90-day mRS of 0-3. The mortality rate was 25%, which is consistent with previous trials.

When the researchers divided patients on the basis of mean time from symptom onset to treatment, they observed no statistically significant differences in the rates of patients with mRS of 0-2 (31% among those treated within a 7-hour window vs. 42% among those treated beyond a 7-hour window) or mRS of 0-3 (49% among those treated within a 7-hour window vs. 55% among those treated beyond a 7-hour window).

"Many patients in the later time group are presenting 15 or 18 hours out from symptom onset, yet they are still achieving a very similar rate of good functional outcome," Mr. Magarik said. "We believe this is because they were selected based on their CT perfusion findings."

Mr. Magarik said that he had no relevant financial disclosures to make.

SAN DIEGO  – When used as a first-line choice for the treatment of acute ischemic stroke secondary to large artery occlusion, the Solitaire FR revascularization device was safe and offered good recanalization rates and clinical outcomes, a multicenter study showed.

The Solitaire FR device, which mechanically removes blood clots from blocked vessels, received CE Mark approval in Europe and has been commercialized internationally by Covidien since November 2009. The Solitaire FR device was cleared in March of 2012 by the Food and Drug Administration.

Photo courtesy Covidien

At the annual meeting of the Society of Neurointerventional Surgery, Dr. Vitor Mendes Pereira presented findings from 141 consecutive patients with acute ischemic stroke who were treated with the Solitaire FR device as first-line treatment to restore blood flow at clinical centers located in Geneva; Barcelona; Essen, Germany; Montpellier, France; Stockholm; and Bern, Switzerland, between March 2009 and July 2010. The researchers used an independent clinical lab to evaluate Thrombolysis in Cerebral Infarction (TICI) scores on pre- and postprocedural angiograms.

Dr. Pereira, one of the investigators who heads the section of interventional neuroradiology at University Hospital of Geneva, said that complete recanalization was defined as TICI 2b or 3 post treatment. He and his associates defined good early neurologic outcome as a National Institutes of Health Stroke Scale (NIHSS) score improvement of 10 or more points or a NIHSS score of 0 or 1 at hospital discharge. They defined favorable outcome as a modified Rankin Scale score of 2 or less at day 90.

The mean age of the 141 patients was 66 years; 44% were women. Their median NIHSS score was 18, and 52% of patients were treated after previous treatment using intravenous tissue plasminogen activator (TPA). Most of the occlusions were located in the anterior circulation (86%), and 46% corresponded to M1 occlusions.

Dr. Pereira reported successful revascularization in 85% of patients with a TICI of 2b or greater, 96% for those with a Thrombolysis in Myocardial Infarction (TIMI) score of 2 or greater, and 83% for those with an Arterial Occlusive Lesion (AOL) score of 3.

Nearly three-quarters of cases (74%) were performed using a balloon-guided catheter. Technical success was achieved in 97.8% of patients, and the median time to groin puncture was 40 minutes. The mean number of passes was 1.8, and 77% of patients achieved recanalization success with up to two passes. Rescue therapy was required in seven cases (4.9%).

Nearly one-third of patients (32%) achieved a good neurologic outcome at hospital discharge and 55% had a modified Rankin Scale score of 2 or less at 90 days. The rate of death at 90 days was 26%, and 6% experienced intracranial hemorrhage.

The study was funded by Covidien. Dr. Pereira disclosed that he is a consultant for Covidien and is the principal investigator for two studies funded by the company.

SAN DIEGO  – When used as a first-line choice for the treatment of acute ischemic stroke secondary to large artery occlusion, the Solitaire FR revascularization device was safe and offered good recanalization rates and clinical outcomes, a multicenter study showed.

The Solitaire FR device, which mechanically removes blood clots from blocked vessels, received CE Mark approval in Europe and has been commercialized internationally by Covidien since November 2009. The Solitaire FR device was cleared in March of 2012 by the Food and Drug Administration.

Photo courtesy Covidien

At the annual meeting of the Society of Neurointerventional Surgery, Dr. Vitor Mendes Pereira presented findings from 141 consecutive patients with acute ischemic stroke who were treated with the Solitaire FR device as first-line treatment to restore blood flow at clinical centers located in Geneva; Barcelona; Essen, Germany; Montpellier, France; Stockholm; and Bern, Switzerland, between March 2009 and July 2010. The researchers used an independent clinical lab to evaluate Thrombolysis in Cerebral Infarction (TICI) scores on pre- and postprocedural angiograms.

Dr. Pereira, one of the investigators who heads the section of interventional neuroradiology at University Hospital of Geneva, said that complete recanalization was defined as TICI 2b or 3 post treatment. He and his associates defined good early neurologic outcome as a National Institutes of Health Stroke Scale (NIHSS) score improvement of 10 or more points or a NIHSS score of 0 or 1 at hospital discharge. They defined favorable outcome as a modified Rankin Scale score of 2 or less at day 90.

The mean age of the 141 patients was 66 years; 44% were women. Their median NIHSS score was 18, and 52% of patients were treated after previous treatment using intravenous tissue plasminogen activator (TPA). Most of the occlusions were located in the anterior circulation (86%), and 46% corresponded to M1 occlusions.

Dr. Pereira reported successful revascularization in 85% of patients with a TICI of 2b or greater, 96% for those with a Thrombolysis in Myocardial Infarction (TIMI) score of 2 or greater, and 83% for those with an Arterial Occlusive Lesion (AOL) score of 3.

Nearly three-quarters of cases (74%) were performed using a balloon-guided catheter. Technical success was achieved in 97.8% of patients, and the median time to groin puncture was 40 minutes. The mean number of passes was 1.8, and 77% of patients achieved recanalization success with up to two passes. Rescue therapy was required in seven cases (4.9%).

Nearly one-third of patients (32%) achieved a good neurologic outcome at hospital discharge and 55% had a modified Rankin Scale score of 2 or less at 90 days. The rate of death at 90 days was 26%, and 6% experienced intracranial hemorrhage.

The study was funded by Covidien. Dr. Pereira disclosed that he is a consultant for Covidien and is the principal investigator for two studies funded by the company.

SAN DIEGO  – When used as a first-line choice for the treatment of acute ischemic stroke secondary to large artery occlusion, the Solitaire FR revascularization device was safe and offered good recanalization rates and clinical outcomes, a multicenter study showed.

The Solitaire FR device, which mechanically removes blood clots from blocked vessels, received CE Mark approval in Europe and has been commercialized internationally by Covidien since November 2009. The Solitaire FR device was cleared in March of 2012 by the Food and Drug Administration.

Photo courtesy Covidien

At the annual meeting of the Society of Neurointerventional Surgery, Dr. Vitor Mendes Pereira presented findings from 141 consecutive patients with acute ischemic stroke who were treated with the Solitaire FR device as first-line treatment to restore blood flow at clinical centers located in Geneva; Barcelona; Essen, Germany; Montpellier, France; Stockholm; and Bern, Switzerland, between March 2009 and July 2010. The researchers used an independent clinical lab to evaluate Thrombolysis in Cerebral Infarction (TICI) scores on pre- and postprocedural angiograms.

Dr. Pereira, one of the investigators who heads the section of interventional neuroradiology at University Hospital of Geneva, said that complete recanalization was defined as TICI 2b or 3 post treatment. He and his associates defined good early neurologic outcome as a National Institutes of Health Stroke Scale (NIHSS) score improvement of 10 or more points or a NIHSS score of 0 or 1 at hospital discharge. They defined favorable outcome as a modified Rankin Scale score of 2 or less at day 90.

The mean age of the 141 patients was 66 years; 44% were women. Their median NIHSS score was 18, and 52% of patients were treated after previous treatment using intravenous tissue plasminogen activator (TPA). Most of the occlusions were located in the anterior circulation (86%), and 46% corresponded to M1 occlusions.

Dr. Pereira reported successful revascularization in 85% of patients with a TICI of 2b or greater, 96% for those with a Thrombolysis in Myocardial Infarction (TIMI) score of 2 or greater, and 83% for those with an Arterial Occlusive Lesion (AOL) score of 3.

Nearly three-quarters of cases (74%) were performed using a balloon-guided catheter. Technical success was achieved in 97.8% of patients, and the median time to groin puncture was 40 minutes. The mean number of passes was 1.8, and 77% of patients achieved recanalization success with up to two passes. Rescue therapy was required in seven cases (4.9%).

Nearly one-third of patients (32%) achieved a good neurologic outcome at hospital discharge and 55% had a modified Rankin Scale score of 2 or less at 90 days. The rate of death at 90 days was 26%, and 6% experienced intracranial hemorrhage.

The study was funded by Covidien. Dr. Pereira disclosed that he is a consultant for Covidien and is the principal investigator for two studies funded by the company.

SAN DIEGO – Stroke patients who are likely to benefit from endovascular reperfusion can be identified on the basis of their MRI profile, results from a multicenter study demonstrated.

"These results are largely independent of stroke onset time," Dr. Michael P. Marks said at the annual meeting of the Society of Neurointerventional Surgery. "Our belief is that if the right patients are identified, it can be shown that endovascular therapy will be of benefit in the treatment of their acute strokes."

Endovascular treatment is increasingly used in the management of acute stroke, said Dr. Marks, an interventional neuroradiologist at Stanford (Calif.) University. "A randomized trial has shown benefit for intra-arterial thrombolytic agents in this setting," he said (JAMA 1999;282:2003-11). "Single-armed prospective studies have shown that thrombectomy devices improve outcome in patients when reperfusion is successfully attained. Nevertheless, tremendous controversy exists because there is an absence of any study with randomized data and concurrent controls. In addition, many questions remain as to which candidates are best suited for revascularization and whether imaging can help identify those patients," Dr. Marks said.

Against this backdrop, he and his associates at nine clinical sites carried out the DEFUSE-2 (Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution Study-2) to identify patients who might fit into a randomized controlled trial. DEFUSE-2 is a prospective study of acute stroke patients who underwent endovascular therapy following MRI. The primary hypothesis was that a target mismatch profile (TMM) could be identified where patients had a relatively small area of injured tissue as seen on diffusion-weighted imaging (DWI) relative to a larger volume of ischemic tissue that was still salvageable as identified by perfusion-weighted imaging (PWI); and that patients with a TMM would respond more favorably to endovascular reperfusion therapy than patients without a TMM.

To be eligible for the trial, patients had to have endovascular therapy started within 12 hours of an anterior circulation stroke. They underwent a baseline MRI within 90 minutes of endovascular therapy, a second MRI following reperfusion in the catheter lab, and a third MRI at 5 days to assess infarct volume. This was followed by clinical assessments at day 30 and day 90 using the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS).

A TMM was defined as PWI volume over the DWI volume of 1.8 or greater, when the PWI volume had a Tmax of more than 6 seconds. PWI reperfusion was defined as a reduction in PWI lesion volume of greater than 50% between baseline and follow-up.

The investigators defined reperfusion as a Thrombolysis in Cerebral Infarction (TICI) score of 2b or 3. In this study, TICI 1 was defined as perfusion past the initial obstruction but little or slow distal perfusion with limited branch filling. TICI 2a was defined as partial perfusion of less than half of the vascular distribution of the occluded artery, TICI 2b was defined as partial perfusion of half or more of the vascular distribution of the occluded artery, and TICI 3 was defined as full perfusion filling of all distal branches.

Dr. Marks reported on outcomes from 78 patients who had a target mismatch and 21 who did not have a target mismatch. The researchers found that reperfusion was associated with a significantly increased odds of a favorable clinical response (odds ratio, 2.8), which was defined as an improvement in NIHSS score between baseline and day 30 of 8 points or more, or an NIHSS score of 0-1 at day 30. This outcome was driven by the target mismatch group, which had significantly greater odds of a favorable response to reperfusion than the no target mismatch group (OR, 5.0 vs. 0.2; P = .004).

A significantly higher percentage of patients in the target mismatch group achieved a 90-day mRS of 0-2 when there was reperfusion, compared with their counterparts in the no target mismatch group (57% vs. 25%), as well as when there was no reperfusion (31% vs. 22%).

The median time to the onset of vascular therapy was 6 hours. "When we divided patients into those started less than 6 hours versus those started greater than 6 hours, the results were very comparable," he said.

Dr. Marks also reported that by day 90, 29% of patients a TICI score of 0-1 achieved an mRS score of 0-2, compared with 25% of patients with a TICI score of 2a, 61% of patients with a score of 2b, and 50% of those with a score of 3. "This was driven by having a target mismatch," he said.

Dr. Marks and his associates are proposing a randomized controlled trial in which the primary hypothesis is that treatment with an approved thrombectomy device within 18-24 hours is more likely to result in a good clinical outcome at 90 days when patients are selected on the basis of a favorable MRI profile.

"The time is right to do this study, because current stentrievers have a high rate of recanalization," Dr. Marks said. "Physiologic imaging can identify patients who will benefit from recanalization in an extended time period."

DEFUSE-2 was funded by the National Institute of Neurological Disorders and Stroke. Dr. Marks said that he had no relevant financial conflicts to disclose.

SAN DIEGO – Stroke patients who are likely to benefit from endovascular reperfusion can be identified on the basis of their MRI profile, results from a multicenter study demonstrated.

"These results are largely independent of stroke onset time," Dr. Michael P. Marks said at the annual meeting of the Society of Neurointerventional Surgery. "Our belief is that if the right patients are identified, it can be shown that endovascular therapy will be of benefit in the treatment of their acute strokes."

Endovascular treatment is increasingly used in the management of acute stroke, said Dr. Marks, an interventional neuroradiologist at Stanford (Calif.) University. "A randomized trial has shown benefit for intra-arterial thrombolytic agents in this setting," he said (JAMA 1999;282:2003-11). "Single-armed prospective studies have shown that thrombectomy devices improve outcome in patients when reperfusion is successfully attained. Nevertheless, tremendous controversy exists because there is an absence of any study with randomized data and concurrent controls. In addition, many questions remain as to which candidates are best suited for revascularization and whether imaging can help identify those patients," Dr. Marks said.

Against this backdrop, he and his associates at nine clinical sites carried out the DEFUSE-2 (Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution Study-2) to identify patients who might fit into a randomized controlled trial. DEFUSE-2 is a prospective study of acute stroke patients who underwent endovascular therapy following MRI. The primary hypothesis was that a target mismatch profile (TMM) could be identified where patients had a relatively small area of injured tissue as seen on diffusion-weighted imaging (DWI) relative to a larger volume of ischemic tissue that was still salvageable as identified by perfusion-weighted imaging (PWI); and that patients with a TMM would respond more favorably to endovascular reperfusion therapy than patients without a TMM.

To be eligible for the trial, patients had to have endovascular therapy started within 12 hours of an anterior circulation stroke. They underwent a baseline MRI within 90 minutes of endovascular therapy, a second MRI following reperfusion in the catheter lab, and a third MRI at 5 days to assess infarct volume. This was followed by clinical assessments at day 30 and day 90 using the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS).

A TMM was defined as PWI volume over the DWI volume of 1.8 or greater, when the PWI volume had a Tmax of more than 6 seconds. PWI reperfusion was defined as a reduction in PWI lesion volume of greater than 50% between baseline and follow-up.

The investigators defined reperfusion as a Thrombolysis in Cerebral Infarction (TICI) score of 2b or 3. In this study, TICI 1 was defined as perfusion past the initial obstruction but little or slow distal perfusion with limited branch filling. TICI 2a was defined as partial perfusion of less than half of the vascular distribution of the occluded artery, TICI 2b was defined as partial perfusion of half or more of the vascular distribution of the occluded artery, and TICI 3 was defined as full perfusion filling of all distal branches.

Dr. Marks reported on outcomes from 78 patients who had a target mismatch and 21 who did not have a target mismatch. The researchers found that reperfusion was associated with a significantly increased odds of a favorable clinical response (odds ratio, 2.8), which was defined as an improvement in NIHSS score between baseline and day 30 of 8 points or more, or an NIHSS score of 0-1 at day 30. This outcome was driven by the target mismatch group, which had significantly greater odds of a favorable response to reperfusion than the no target mismatch group (OR, 5.0 vs. 0.2; P = .004).

A significantly higher percentage of patients in the target mismatch group achieved a 90-day mRS of 0-2 when there was reperfusion, compared with their counterparts in the no target mismatch group (57% vs. 25%), as well as when there was no reperfusion (31% vs. 22%).

The median time to the onset of vascular therapy was 6 hours. "When we divided patients into those started less than 6 hours versus those started greater than 6 hours, the results were very comparable," he said.

Dr. Marks also reported that by day 90, 29% of patients a TICI score of 0-1 achieved an mRS score of 0-2, compared with 25% of patients with a TICI score of 2a, 61% of patients with a score of 2b, and 50% of those with a score of 3. "This was driven by having a target mismatch," he said.

Dr. Marks and his associates are proposing a randomized controlled trial in which the primary hypothesis is that treatment with an approved thrombectomy device within 18-24 hours is more likely to result in a good clinical outcome at 90 days when patients are selected on the basis of a favorable MRI profile.

"The time is right to do this study, because current stentrievers have a high rate of recanalization," Dr. Marks said. "Physiologic imaging can identify patients who will benefit from recanalization in an extended time period."

DEFUSE-2 was funded by the National Institute of Neurological Disorders and Stroke. Dr. Marks said that he had no relevant financial conflicts to disclose.

SAN DIEGO – Stroke patients who are likely to benefit from endovascular reperfusion can be identified on the basis of their MRI profile, results from a multicenter study demonstrated.

"These results are largely independent of stroke onset time," Dr. Michael P. Marks said at the annual meeting of the Society of Neurointerventional Surgery. "Our belief is that if the right patients are identified, it can be shown that endovascular therapy will be of benefit in the treatment of their acute strokes."

Endovascular treatment is increasingly used in the management of acute stroke, said Dr. Marks, an interventional neuroradiologist at Stanford (Calif.) University. "A randomized trial has shown benefit for intra-arterial thrombolytic agents in this setting," he said (JAMA 1999;282:2003-11). "Single-armed prospective studies have shown that thrombectomy devices improve outcome in patients when reperfusion is successfully attained. Nevertheless, tremendous controversy exists because there is an absence of any study with randomized data and concurrent controls. In addition, many questions remain as to which candidates are best suited for revascularization and whether imaging can help identify those patients," Dr. Marks said.

Against this backdrop, he and his associates at nine clinical sites carried out the DEFUSE-2 (Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution Study-2) to identify patients who might fit into a randomized controlled trial. DEFUSE-2 is a prospective study of acute stroke patients who underwent endovascular therapy following MRI. The primary hypothesis was that a target mismatch profile (TMM) could be identified where patients had a relatively small area of injured tissue as seen on diffusion-weighted imaging (DWI) relative to a larger volume of ischemic tissue that was still salvageable as identified by perfusion-weighted imaging (PWI); and that patients with a TMM would respond more favorably to endovascular reperfusion therapy than patients without a TMM.

To be eligible for the trial, patients had to have endovascular therapy started within 12 hours of an anterior circulation stroke. They underwent a baseline MRI within 90 minutes of endovascular therapy, a second MRI following reperfusion in the catheter lab, and a third MRI at 5 days to assess infarct volume. This was followed by clinical assessments at day 30 and day 90 using the National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS).

A TMM was defined as PWI volume over the DWI volume of 1.8 or greater, when the PWI volume had a Tmax of more than 6 seconds. PWI reperfusion was defined as a reduction in PWI lesion volume of greater than 50% between baseline and follow-up.

The investigators defined reperfusion as a Thrombolysis in Cerebral Infarction (TICI) score of 2b or 3. In this study, TICI 1 was defined as perfusion past the initial obstruction but little or slow distal perfusion with limited branch filling. TICI 2a was defined as partial perfusion of less than half of the vascular distribution of the occluded artery, TICI 2b was defined as partial perfusion of half or more of the vascular distribution of the occluded artery, and TICI 3 was defined as full perfusion filling of all distal branches.

Dr. Marks reported on outcomes from 78 patients who had a target mismatch and 21 who did not have a target mismatch. The researchers found that reperfusion was associated with a significantly increased odds of a favorable clinical response (odds ratio, 2.8), which was defined as an improvement in NIHSS score between baseline and day 30 of 8 points or more, or an NIHSS score of 0-1 at day 30. This outcome was driven by the target mismatch group, which had significantly greater odds of a favorable response to reperfusion than the no target mismatch group (OR, 5.0 vs. 0.2; P = .004).

A significantly higher percentage of patients in the target mismatch group achieved a 90-day mRS of 0-2 when there was reperfusion, compared with their counterparts in the no target mismatch group (57% vs. 25%), as well as when there was no reperfusion (31% vs. 22%).

The median time to the onset of vascular therapy was 6 hours. "When we divided patients into those started less than 6 hours versus those started greater than 6 hours, the results were very comparable," he said.

Dr. Marks also reported that by day 90, 29% of patients a TICI score of 0-1 achieved an mRS score of 0-2, compared with 25% of patients with a TICI score of 2a, 61% of patients with a score of 2b, and 50% of those with a score of 3. "This was driven by having a target mismatch," he said.

Dr. Marks and his associates are proposing a randomized controlled trial in which the primary hypothesis is that treatment with an approved thrombectomy device within 18-24 hours is more likely to result in a good clinical outcome at 90 days when patients are selected on the basis of a favorable MRI profile.

"The time is right to do this study, because current stentrievers have a high rate of recanalization," Dr. Marks said. "Physiologic imaging can identify patients who will benefit from recanalization in an extended time period."

DEFUSE-2 was funded by the National Institute of Neurological Disorders and Stroke. Dr. Marks said that he had no relevant financial conflicts to disclose.

SAN DIEGO – Of the many scales at a clinician’s disposal to measure acute pain, the three most commonly used are the Numerical Rating Scale, the Verbal Rating Scale, and the Visual Analog Scale, Dr. Jeffrey A. Stone said at the annual meeting of the Society of Neurointerventional Surgery.

"All of these scales have been shown to be statistically reliable and valid," said Dr. Stone, associate professor of neurointerventional surgery in the radiology department at the Mayo Clinic, Jacksonville, Fla. In his clinical experience, most patients prefer the Numerical Rating Scale (NRS) and the Verbal Rating Scale (VRS) because they are easy to use. "The other advantage is that these can be conducted by telephone or electronic diaries," he said.

The NRS is a familiar and commonly used 0-10 scale, where 0 = no pain, 1-3 = mild pain, 4-6 = moderate pain, and 7-10 = severe pain. "If patients tell you, ‘I’m a 5 out of 10,’ that can be difficult to gauge, particularly in the elderly," Dr. Stone said. "The VRS, a four-scale system ranging from no pain up to severe pain, is somewhat simpler and correlates well with the NRS."

With the Visual Analog Scale, patients are asked to make a vertical slash on a 100-mm line to denote their level of pain. "I use this scale a lot, but it can be cumbersome, particularly with follow-up," he said.

Factors to consider in the backdrop of pain intensity include rescue analgesics, which may be prescribed by other physicians for sleep or anxiety, or may be used to prevent pain from increased activity or to treat unrelated pain. "Another factor is concomitant pain treatments, such as acupuncture and chiropractic treatments," Dr. Stone said. "In addition, patients enrolled in the placebo group of a clinical trial are generally expected to have more pain medication use compared with those in an efficacious treatment group."

Other distinct components of pain include pain sensation and pain affect. Pain sensation "is the quality of the pain, such as burning, throbbing, or sharp pain versus dull pain," Dr. Stone said. "There are also temporal aspects to pain, such as variability of intensity over time; time to onset of meaningful pain relief; durability of pain relief; and the frequency, duration, and intensity of pain episodes. Pain affect is the mental distress caused by the pain."

Global pain assessments for pain sensation and pain affect include a modification of the McGill Pain Questionnaire (MPQ), known as the short-form MPQ, and the Brief Pain Inventory (BPI), which was adapted from the Wisconsin Brief Pain Questionnaire. The short-form MPQ contains 15 sensory and affective descriptors, while the BPI "does a much better job measuring the temporal aspect of pain and is often used in conjunction with the short-form MPQ," Dr. Stone said.

Two other core pain outcome domains are physical function and emotional function. Effective outcome measures for these domains include the Oswestry Disability Index (ODI), the Short Form-36 (SF-36), the Roland-Morris Disability Questionnaire (RMQ) and the Pain Disability Index (PDI).

The ODI, a 10-item questionnaire, "has been used in many pain trials," he said. "It looks at pain intensity but also other things such as lifting, the ability to walk, social life, sexual activity, and sleep cycle. It is a very accurate way to look at a patient’s global disability from pain."

He described the SF-36 as "a little bit more cumbersome for patients to complete" in measuring physical and emotional function. This tool provides an eight-scale profile of functional health and well-being scores, as well as a psychometric-based physical and mental health summary.

The 24-item RMQ consists of yes/no questions intended to measure self-perceived disability, while the 7-question PDI measures pain interference in physical and psychosocial role performance.

In a later interview, Dr. Stone said that the NRS, VRS, and VAS instruments can be used in hospitalized patients. Outcome measures such as the ODI and the RMQ "would not be very useful, as they ask many functional questions such as sex life [and] activity level, which would not be applicable to a hospitalized patient."

Dr. Stone said that he had no relevant financial disclosures to make.

SAN DIEGO – Of the many scales at a clinician’s disposal to measure acute pain, the three most commonly used are the Numerical Rating Scale, the Verbal Rating Scale, and the Visual Analog Scale, Dr. Jeffrey A. Stone said at the annual meeting of the Society of Neurointerventional Surgery.

"All of these scales have been shown to be statistically reliable and valid," said Dr. Stone, associate professor of neurointerventional surgery in the radiology department at the Mayo Clinic, Jacksonville, Fla. In his clinical experience, most patients prefer the Numerical Rating Scale (NRS) and the Verbal Rating Scale (VRS) because they are easy to use. "The other advantage is that these can be conducted by telephone or electronic diaries," he said.

The NRS is a familiar and commonly used 0-10 scale, where 0 = no pain, 1-3 = mild pain, 4-6 = moderate pain, and 7-10 = severe pain. "If patients tell you, ‘I’m a 5 out of 10,’ that can be difficult to gauge, particularly in the elderly," Dr. Stone said. "The VRS, a four-scale system ranging from no pain up to severe pain, is somewhat simpler and correlates well with the NRS."

With the Visual Analog Scale, patients are asked to make a vertical slash on a 100-mm line to denote their level of pain. "I use this scale a lot, but it can be cumbersome, particularly with follow-up," he said.

Factors to consider in the backdrop of pain intensity include rescue analgesics, which may be prescribed by other physicians for sleep or anxiety, or may be used to prevent pain from increased activity or to treat unrelated pain. "Another factor is concomitant pain treatments, such as acupuncture and chiropractic treatments," Dr. Stone said. "In addition, patients enrolled in the placebo group of a clinical trial are generally expected to have more pain medication use compared with those in an efficacious treatment group."

Other distinct components of pain include pain sensation and pain affect. Pain sensation "is the quality of the pain, such as burning, throbbing, or sharp pain versus dull pain," Dr. Stone said. "There are also temporal aspects to pain, such as variability of intensity over time; time to onset of meaningful pain relief; durability of pain relief; and the frequency, duration, and intensity of pain episodes. Pain affect is the mental distress caused by the pain."

Global pain assessments for pain sensation and pain affect include a modification of the McGill Pain Questionnaire (MPQ), known as the short-form MPQ, and the Brief Pain Inventory (BPI), which was adapted from the Wisconsin Brief Pain Questionnaire. The short-form MPQ contains 15 sensory and affective descriptors, while the BPI "does a much better job measuring the temporal aspect of pain and is often used in conjunction with the short-form MPQ," Dr. Stone said.

Two other core pain outcome domains are physical function and emotional function. Effective outcome measures for these domains include the Oswestry Disability Index (ODI), the Short Form-36 (SF-36), the Roland-Morris Disability Questionnaire (RMQ) and the Pain Disability Index (PDI).

The ODI, a 10-item questionnaire, "has been used in many pain trials," he said. "It looks at pain intensity but also other things such as lifting, the ability to walk, social life, sexual activity, and sleep cycle. It is a very accurate way to look at a patient’s global disability from pain."

He described the SF-36 as "a little bit more cumbersome for patients to complete" in measuring physical and emotional function. This tool provides an eight-scale profile of functional health and well-being scores, as well as a psychometric-based physical and mental health summary.

The 24-item RMQ consists of yes/no questions intended to measure self-perceived disability, while the 7-question PDI measures pain interference in physical and psychosocial role performance.

In a later interview, Dr. Stone said that the NRS, VRS, and VAS instruments can be used in hospitalized patients. Outcome measures such as the ODI and the RMQ "would not be very useful, as they ask many functional questions such as sex life [and] activity level, which would not be applicable to a hospitalized patient."

Dr. Stone said that he had no relevant financial disclosures to make.

SAN DIEGO – Of the many scales at a clinician’s disposal to measure acute pain, the three most commonly used are the Numerical Rating Scale, the Verbal Rating Scale, and the Visual Analog Scale, Dr. Jeffrey A. Stone said at the annual meeting of the Society of Neurointerventional Surgery.

"All of these scales have been shown to be statistically reliable and valid," said Dr. Stone, associate professor of neurointerventional surgery in the radiology department at the Mayo Clinic, Jacksonville, Fla. In his clinical experience, most patients prefer the Numerical Rating Scale (NRS) and the Verbal Rating Scale (VRS) because they are easy to use. "The other advantage is that these can be conducted by telephone or electronic diaries," he said.

The NRS is a familiar and commonly used 0-10 scale, where 0 = no pain, 1-3 = mild pain, 4-6 = moderate pain, and 7-10 = severe pain. "If patients tell you, ‘I’m a 5 out of 10,’ that can be difficult to gauge, particularly in the elderly," Dr. Stone said. "The VRS, a four-scale system ranging from no pain up to severe pain, is somewhat simpler and correlates well with the NRS."

With the Visual Analog Scale, patients are asked to make a vertical slash on a 100-mm line to denote their level of pain. "I use this scale a lot, but it can be cumbersome, particularly with follow-up," he said.

Factors to consider in the backdrop of pain intensity include rescue analgesics, which may be prescribed by other physicians for sleep or anxiety, or may be used to prevent pain from increased activity or to treat unrelated pain. "Another factor is concomitant pain treatments, such as acupuncture and chiropractic treatments," Dr. Stone said. "In addition, patients enrolled in the placebo group of a clinical trial are generally expected to have more pain medication use compared with those in an efficacious treatment group."

Other distinct components of pain include pain sensation and pain affect. Pain sensation "is the quality of the pain, such as burning, throbbing, or sharp pain versus dull pain," Dr. Stone said. "There are also temporal aspects to pain, such as variability of intensity over time; time to onset of meaningful pain relief; durability of pain relief; and the frequency, duration, and intensity of pain episodes. Pain affect is the mental distress caused by the pain."

Global pain assessments for pain sensation and pain affect include a modification of the McGill Pain Questionnaire (MPQ), known as the short-form MPQ, and the Brief Pain Inventory (BPI), which was adapted from the Wisconsin Brief Pain Questionnaire. The short-form MPQ contains 15 sensory and affective descriptors, while the BPI "does a much better job measuring the temporal aspect of pain and is often used in conjunction with the short-form MPQ," Dr. Stone said.

Two other core pain outcome domains are physical function and emotional function. Effective outcome measures for these domains include the Oswestry Disability Index (ODI), the Short Form-36 (SF-36), the Roland-Morris Disability Questionnaire (RMQ) and the Pain Disability Index (PDI).

The ODI, a 10-item questionnaire, "has been used in many pain trials," he said. "It looks at pain intensity but also other things such as lifting, the ability to walk, social life, sexual activity, and sleep cycle. It is a very accurate way to look at a patient’s global disability from pain."

He described the SF-36 as "a little bit more cumbersome for patients to complete" in measuring physical and emotional function. This tool provides an eight-scale profile of functional health and well-being scores, as well as a psychometric-based physical and mental health summary.

The 24-item RMQ consists of yes/no questions intended to measure self-perceived disability, while the 7-question PDI measures pain interference in physical and psychosocial role performance.

In a later interview, Dr. Stone said that the NRS, VRS, and VAS instruments can be used in hospitalized patients. Outcome measures such as the ODI and the RMQ "would not be very useful, as they ask many functional questions such as sex life [and] activity level, which would not be applicable to a hospitalized patient."

Dr. Stone said that he had no relevant financial disclosures to make.

SAN DIEGO – Patients who presented with acute ischemic stroke secondary to a large-vessel occlusion in the anterior circulation were nearly four times more likely to have a favorable outcome at 90 days if they underwent endovascular therapy than if they underwent intravenous rt-PA therapy in a single-center study.

"Large-vessel occlusions cause almost half of acute ischemic strokes and portend a poor prognosis if untreated," Dr. Ansaar T. Rai said at the annual meeting of the Society of Neurointerventional Surgery. "There are limited data comparing IV rt-PA [recombinant tissue-type plasminogen activator] and endovascular therapy outcomes for large-vessel occlusions. We need evidence to define the target population for endovascular therapy. We need to design meaningful trials around this target population and provide reasonable outcome expectations and information to patients presenting with acute ischemic stroke."

Dr. Rai, an interventional neuroradiologist with West Virginia University, Morgantown, presented findings from a single-center, retrospective study of 223 patients with an intracranial vascular occlusion in the anterior circulation on baseline CT angiography (CTA). The patients had undergone either endovascular therapy (EVT) or IV rt-PA treatment (IVT), but not both. Large-vessel occlusion on admission CTA was defined as involvement of the internal carotid artery terminus (ICA-T), the middle cerebral artery main stem with or without bifurcation involvement (M1), or isolated involvement of the proximal M2 branches.

The primary outcome was 90-day favorable outcome, defined as a modified Rankin score of 0-2, while the safety outcomes were mortality and significant parenchymal hemorrhage.

Dr. Rai reported on results from 100 patients in the IVT group and 123 patients in the EVT group. The mean age of patients was 72 years, 56% were female, and their mean baseline National Institutes of Health Stroke Scale (NIHSS) score was 19.1. Nearly half of the occlusions (48%) involved M1, 32% involved M2, and 20% involved ICA-T.

Among all patients, a favorable outcome occurred in 81 (36.3%), and mortality occurred in 81 (36.3%).

A comparison of baseline characteristics revealed that patients in the EVT group were significantly younger than those in the IVT group (69 vs. 76 years; P = .0002), had significantly more M1 occlusions (56% vs. 38%; P = .007), and had significantly fewer M2 occlusions (20% vs. 46%; P = .0002).

A significantly greater proportion of patients in the EVT group had a favorable outcome compared with those in the IVT group (45% vs. 26%, P = .003; odds ratio, 2.3), yet there were no significant differences between the groups in terms of mortality (32% vs. 42%; P = .10) or in the rate of significant hemorrhage (14% vs. 10%; P = .38).

For all occlusion sites, patients in the EVT group had significantly better outcomes than did patients in the IVT group. For ICA-T occlusions, 27% of patients in the EVT group achieved a good outcome, compared with 0% in the IVT group (P = .004). Similar associations were observed for M1 lesions (41% vs. 11%, respectively; P = .0006) and for M2 lesions (76% vs. 48%; P = .01).

The researchers observed that at all sites of occlusion, a higher proportion of patients younger than 80 years had favorable outcomes, compared with patients aged 80 and older, especially those with proximal occlusions.

Multivariate analysis controlling for age and occlusion site composition demonstrated that patients in the EVT group were 3.9 times more likely to achieve a favorable outcome compared with their counterparts in the IVT group (P = .0004).

"In the last decade, we’ve seen significant technological advancement in our techniques and devices for stroke therapy," Dr. Rai commented. "The number of stroke treatments has not changed significantly. We need a paradigm shift in how we select patients for therapy, an appropriate intervention, and a comprehensive strategy."

Dr. Rai acknowledged certain limitations of the study, including its retrospective design and a bias in selecting EVT patients.

He said that he had no relevant financial disclosures.

SAN DIEGO – Patients who presented with acute ischemic stroke secondary to a large-vessel occlusion in the anterior circulation were nearly four times more likely to have a favorable outcome at 90 days if they underwent endovascular therapy than if they underwent intravenous rt-PA therapy in a single-center study.

"Large-vessel occlusions cause almost half of acute ischemic strokes and portend a poor prognosis if untreated," Dr. Ansaar T. Rai said at the annual meeting of the Society of Neurointerventional Surgery. "There are limited data comparing IV rt-PA [recombinant tissue-type plasminogen activator] and endovascular therapy outcomes for large-vessel occlusions. We need evidence to define the target population for endovascular therapy. We need to design meaningful trials around this target population and provide reasonable outcome expectations and information to patients presenting with acute ischemic stroke."

Dr. Rai, an interventional neuroradiologist with West Virginia University, Morgantown, presented findings from a single-center, retrospective study of 223 patients with an intracranial vascular occlusion in the anterior circulation on baseline CT angiography (CTA). The patients had undergone either endovascular therapy (EVT) or IV rt-PA treatment (IVT), but not both. Large-vessel occlusion on admission CTA was defined as involvement of the internal carotid artery terminus (ICA-T), the middle cerebral artery main stem with or without bifurcation involvement (M1), or isolated involvement of the proximal M2 branches.

The primary outcome was 90-day favorable outcome, defined as a modified Rankin score of 0-2, while the safety outcomes were mortality and significant parenchymal hemorrhage.

Dr. Rai reported on results from 100 patients in the IVT group and 123 patients in the EVT group. The mean age of patients was 72 years, 56% were female, and their mean baseline National Institutes of Health Stroke Scale (NIHSS) score was 19.1. Nearly half of the occlusions (48%) involved M1, 32% involved M2, and 20% involved ICA-T.

Among all patients, a favorable outcome occurred in 81 (36.3%), and mortality occurred in 81 (36.3%).

A comparison of baseline characteristics revealed that patients in the EVT group were significantly younger than those in the IVT group (69 vs. 76 years; P = .0002), had significantly more M1 occlusions (56% vs. 38%; P = .007), and had significantly fewer M2 occlusions (20% vs. 46%; P = .0002).

A significantly greater proportion of patients in the EVT group had a favorable outcome compared with those in the IVT group (45% vs. 26%, P = .003; odds ratio, 2.3), yet there were no significant differences between the groups in terms of mortality (32% vs. 42%; P = .10) or in the rate of significant hemorrhage (14% vs. 10%; P = .38).

For all occlusion sites, patients in the EVT group had significantly better outcomes than did patients in the IVT group. For ICA-T occlusions, 27% of patients in the EVT group achieved a good outcome, compared with 0% in the IVT group (P = .004). Similar associations were observed for M1 lesions (41% vs. 11%, respectively; P = .0006) and for M2 lesions (76% vs. 48%; P = .01).

The researchers observed that at all sites of occlusion, a higher proportion of patients younger than 80 years had favorable outcomes, compared with patients aged 80 and older, especially those with proximal occlusions.

Multivariate analysis controlling for age and occlusion site composition demonstrated that patients in the EVT group were 3.9 times more likely to achieve a favorable outcome compared with their counterparts in the IVT group (P = .0004).

"In the last decade, we’ve seen significant technological advancement in our techniques and devices for stroke therapy," Dr. Rai commented. "The number of stroke treatments has not changed significantly. We need a paradigm shift in how we select patients for therapy, an appropriate intervention, and a comprehensive strategy."

Dr. Rai acknowledged certain limitations of the study, including its retrospective design and a bias in selecting EVT patients.

He said that he had no relevant financial disclosures.

SAN DIEGO – Patients who presented with acute ischemic stroke secondary to a large-vessel occlusion in the anterior circulation were nearly four times more likely to have a favorable outcome at 90 days if they underwent endovascular therapy than if they underwent intravenous rt-PA therapy in a single-center study.

"Large-vessel occlusions cause almost half of acute ischemic strokes and portend a poor prognosis if untreated," Dr. Ansaar T. Rai said at the annual meeting of the Society of Neurointerventional Surgery. "There are limited data comparing IV rt-PA [recombinant tissue-type plasminogen activator] and endovascular therapy outcomes for large-vessel occlusions. We need evidence to define the target population for endovascular therapy. We need to design meaningful trials around this target population and provide reasonable outcome expectations and information to patients presenting with acute ischemic stroke."

Dr. Rai, an interventional neuroradiologist with West Virginia University, Morgantown, presented findings from a single-center, retrospective study of 223 patients with an intracranial vascular occlusion in the anterior circulation on baseline CT angiography (CTA). The patients had undergone either endovascular therapy (EVT) or IV rt-PA treatment (IVT), but not both. Large-vessel occlusion on admission CTA was defined as involvement of the internal carotid artery terminus (ICA-T), the middle cerebral artery main stem with or without bifurcation involvement (M1), or isolated involvement of the proximal M2 branches.

The primary outcome was 90-day favorable outcome, defined as a modified Rankin score of 0-2, while the safety outcomes were mortality and significant parenchymal hemorrhage.

Dr. Rai reported on results from 100 patients in the IVT group and 123 patients in the EVT group. The mean age of patients was 72 years, 56% were female, and their mean baseline National Institutes of Health Stroke Scale (NIHSS) score was 19.1. Nearly half of the occlusions (48%) involved M1, 32% involved M2, and 20% involved ICA-T.

Among all patients, a favorable outcome occurred in 81 (36.3%), and mortality occurred in 81 (36.3%).

A comparison of baseline characteristics revealed that patients in the EVT group were significantly younger than those in the IVT group (69 vs. 76 years; P = .0002), had significantly more M1 occlusions (56% vs. 38%; P = .007), and had significantly fewer M2 occlusions (20% vs. 46%; P = .0002).

A significantly greater proportion of patients in the EVT group had a favorable outcome compared with those in the IVT group (45% vs. 26%, P = .003; odds ratio, 2.3), yet there were no significant differences between the groups in terms of mortality (32% vs. 42%; P = .10) or in the rate of significant hemorrhage (14% vs. 10%; P = .38).

For all occlusion sites, patients in the EVT group had significantly better outcomes than did patients in the IVT group. For ICA-T occlusions, 27% of patients in the EVT group achieved a good outcome, compared with 0% in the IVT group (P = .004). Similar associations were observed for M1 lesions (41% vs. 11%, respectively; P = .0006) and for M2 lesions (76% vs. 48%; P = .01).

The researchers observed that at all sites of occlusion, a higher proportion of patients younger than 80 years had favorable outcomes, compared with patients aged 80 and older, especially those with proximal occlusions.

Multivariate analysis controlling for age and occlusion site composition demonstrated that patients in the EVT group were 3.9 times more likely to achieve a favorable outcome compared with their counterparts in the IVT group (P = .0004).

"In the last decade, we’ve seen significant technological advancement in our techniques and devices for stroke therapy," Dr. Rai commented. "The number of stroke treatments has not changed significantly. We need a paradigm shift in how we select patients for therapy, an appropriate intervention, and a comprehensive strategy."

Dr. Rai acknowledged certain limitations of the study, including its retrospective design and a bias in selecting EVT patients.

He said that he had no relevant financial disclosures.

SAN DIEGO – Interim results from an ongoing study demonstrated that that a higher pretreatment Alberta Stroke Program Early CT Score on computed tomography angiogram images is associated with better outcome following endovascular therapy.

"There is no standard imaging approach for endovascular therapy patient selection," Dr. Donald Frei said at the annual meeting of the Society of Neurointerventional Surgery. "We’re trying to improve time from door to CT imaging and time from imaging to groin puncture, but we also need to be a little bit more sophisticated about patient selection. That’s what we tried to do in this study."

For the analysis, Dr. Frei, director of neurointerventional surgery for Radiology Imaging Associates/Swedish Medical Center in Denver, and his associates at 15 centers evaluated the influence of pretreatment ASPECTS from CTA source image on outcomes following endovascular therapy in the START (Stroke Treatment and Revascularization Therapy) trial, a prospective, single-arm multicenter trial that set out to study the influence of pretreatment core infarct size in 147 patients undergoing endovascular stroke therapy with the Penumbra system.

Imaging methods were at the direction of each investigator and included noncontrast CT, CTA-SI (CTA source images), CT perfusion, or MRI diffuse imaging. The current analysis focused on the preliminary CTA-SI results. ASPECTS was graded in a blinded fashion and analyzed according to a prior classification (0-4, 5-7, or 8-10) and the entire scale. Clinical outcomes were dichotomized as 90-day modified Rankin Scale (mRS) scores of 0-2 (good) vs. 3-6.

Dr. Frei reported interim results from 77 patients who met study criteria. Their mean age was 66 years, 56% were women, and their mean National Institutes of Health Stroke Scale score was 19. The majority of target vessel occlusions were in the middle cerebral artery (75.3%), followed by internal carotid artery (22.1%), and other areas (2.6%). (Dr. Frei noted that results from all 147 patients are expected to be presented at the upcoming International Stroke Conference.)

The median pre-ASPECTS on CTA-SI was 6. Of the 77 patients, 20 (26%) had a score of 0-4, 43 (56%) had a score of 5-7, and 14 (18%) had a score of 8-10.

Dr. Frei, who is also a member of the SNIS Executive Committee, reported that the rate of TIMI (Thrombolysis in Myocardial Infarction) 2-3 revascularization was 85.3%, the median time from groin puncture to aspiration discontinuation was 71.5 minutes, and 48.1% of patients achieved a good 90-day clinical outcome.

The mortality rate was 28.6%, and 32.5% suffered from intracranial hemorrhage. Of these, 20.8% were asymptomatic.

In general, the higher the pretreatment ASPECTS on CTA-SI, the better the outcome. For example, the rate of good outcomes was 20% for those with a pretreatment ASPECTS of 0-4, 56% for 5-7, and 64% for 8-10 (P = .08 for all). After adjusting for age and stroke severity, the researchers determined that a pre-ASPECTS score of 5-10 was an independent predictor of good outcome (odds ratio, 6.8; P = .006).

Univariate analysis demonstrated the following significant predictors of good outcomes: pretreatment ASPECTS greater than 4 (P = .0043), younger age (P = .01), lower pretreatment NIHSS (P = .04), shorter time from groin puncture to discontinuation of aspiration (P = .0004), and revascularization time (P = .0001).

In a prepared statement, Dr. Frei noted that although thousands of men and women suffer a stroke every day, "only a small percentage of those affected are treated with endovascular therapy. This study strongly suggests that a simple ASPECTS reading from a fast, easy-to-obtain CTA source image can guide patient selection for endovascular therapy, particularly those most likely to benefit from the Penumbra System" beyond the 3- to 4.5-hour window.

The START trial was sponsored by Penumbra Inc.

Dr. Frei said that he had no relevant financial disclosures to make.

SAN DIEGO – Interim results from an ongoing study demonstrated that that a higher pretreatment Alberta Stroke Program Early CT Score on computed tomography angiogram images is associated with better outcome following endovascular therapy.

"There is no standard imaging approach for endovascular therapy patient selection," Dr. Donald Frei said at the annual meeting of the Society of Neurointerventional Surgery. "We’re trying to improve time from door to CT imaging and time from imaging to groin puncture, but we also need to be a little bit more sophisticated about patient selection. That’s what we tried to do in this study."

For the analysis, Dr. Frei, director of neurointerventional surgery for Radiology Imaging Associates/Swedish Medical Center in Denver, and his associates at 15 centers evaluated the influence of pretreatment ASPECTS from CTA source image on outcomes following endovascular therapy in the START (Stroke Treatment and Revascularization Therapy) trial, a prospective, single-arm multicenter trial that set out to study the influence of pretreatment core infarct size in 147 patients undergoing endovascular stroke therapy with the Penumbra system.

Imaging methods were at the direction of each investigator and included noncontrast CT, CTA-SI (CTA source images), CT perfusion, or MRI diffuse imaging. The current analysis focused on the preliminary CTA-SI results. ASPECTS was graded in a blinded fashion and analyzed according to a prior classification (0-4, 5-7, or 8-10) and the entire scale. Clinical outcomes were dichotomized as 90-day modified Rankin Scale (mRS) scores of 0-2 (good) vs. 3-6.

Dr. Frei reported interim results from 77 patients who met study criteria. Their mean age was 66 years, 56% were women, and their mean National Institutes of Health Stroke Scale score was 19. The majority of target vessel occlusions were in the middle cerebral artery (75.3%), followed by internal carotid artery (22.1%), and other areas (2.6%). (Dr. Frei noted that results from all 147 patients are expected to be presented at the upcoming International Stroke Conference.)

The median pre-ASPECTS on CTA-SI was 6. Of the 77 patients, 20 (26%) had a score of 0-4, 43 (56%) had a score of 5-7, and 14 (18%) had a score of 8-10.

Dr. Frei, who is also a member of the SNIS Executive Committee, reported that the rate of TIMI (Thrombolysis in Myocardial Infarction) 2-3 revascularization was 85.3%, the median time from groin puncture to aspiration discontinuation was 71.5 minutes, and 48.1% of patients achieved a good 90-day clinical outcome.

The mortality rate was 28.6%, and 32.5% suffered from intracranial hemorrhage. Of these, 20.8% were asymptomatic.

In general, the higher the pretreatment ASPECTS on CTA-SI, the better the outcome. For example, the rate of good outcomes was 20% for those with a pretreatment ASPECTS of 0-4, 56% for 5-7, and 64% for 8-10 (P = .08 for all). After adjusting for age and stroke severity, the researchers determined that a pre-ASPECTS score of 5-10 was an independent predictor of good outcome (odds ratio, 6.8; P = .006).

Univariate analysis demonstrated the following significant predictors of good outcomes: pretreatment ASPECTS greater than 4 (P = .0043), younger age (P = .01), lower pretreatment NIHSS (P = .04), shorter time from groin puncture to discontinuation of aspiration (P = .0004), and revascularization time (P = .0001).

In a prepared statement, Dr. Frei noted that although thousands of men and women suffer a stroke every day, "only a small percentage of those affected are treated with endovascular therapy. This study strongly suggests that a simple ASPECTS reading from a fast, easy-to-obtain CTA source image can guide patient selection for endovascular therapy, particularly those most likely to benefit from the Penumbra System" beyond the 3- to 4.5-hour window.

The START trial was sponsored by Penumbra Inc.

Dr. Frei said that he had no relevant financial disclosures to make.

SAN DIEGO – Interim results from an ongoing study demonstrated that that a higher pretreatment Alberta Stroke Program Early CT Score on computed tomography angiogram images is associated with better outcome following endovascular therapy.

"There is no standard imaging approach for endovascular therapy patient selection," Dr. Donald Frei said at the annual meeting of the Society of Neurointerventional Surgery. "We’re trying to improve time from door to CT imaging and time from imaging to groin puncture, but we also need to be a little bit more sophisticated about patient selection. That’s what we tried to do in this study."

For the analysis, Dr. Frei, director of neurointerventional surgery for Radiology Imaging Associates/Swedish Medical Center in Denver, and his associates at 15 centers evaluated the influence of pretreatment ASPECTS from CTA source image on outcomes following endovascular therapy in the START (Stroke Treatment and Revascularization Therapy) trial, a prospective, single-arm multicenter trial that set out to study the influence of pretreatment core infarct size in 147 patients undergoing endovascular stroke therapy with the Penumbra system.

Imaging methods were at the direction of each investigator and included noncontrast CT, CTA-SI (CTA source images), CT perfusion, or MRI diffuse imaging. The current analysis focused on the preliminary CTA-SI results. ASPECTS was graded in a blinded fashion and analyzed according to a prior classification (0-4, 5-7, or 8-10) and the entire scale. Clinical outcomes were dichotomized as 90-day modified Rankin Scale (mRS) scores of 0-2 (good) vs. 3-6.

Dr. Frei reported interim results from 77 patients who met study criteria. Their mean age was 66 years, 56% were women, and their mean National Institutes of Health Stroke Scale score was 19. The majority of target vessel occlusions were in the middle cerebral artery (75.3%), followed by internal carotid artery (22.1%), and other areas (2.6%). (Dr. Frei noted that results from all 147 patients are expected to be presented at the upcoming International Stroke Conference.)

The median pre-ASPECTS on CTA-SI was 6. Of the 77 patients, 20 (26%) had a score of 0-4, 43 (56%) had a score of 5-7, and 14 (18%) had a score of 8-10.

Dr. Frei, who is also a member of the SNIS Executive Committee, reported that the rate of TIMI (Thrombolysis in Myocardial Infarction) 2-3 revascularization was 85.3%, the median time from groin puncture to aspiration discontinuation was 71.5 minutes, and 48.1% of patients achieved a good 90-day clinical outcome.

The mortality rate was 28.6%, and 32.5% suffered from intracranial hemorrhage. Of these, 20.8% were asymptomatic.

In general, the higher the pretreatment ASPECTS on CTA-SI, the better the outcome. For example, the rate of good outcomes was 20% for those with a pretreatment ASPECTS of 0-4, 56% for 5-7, and 64% for 8-10 (P = .08 for all). After adjusting for age and stroke severity, the researchers determined that a pre-ASPECTS score of 5-10 was an independent predictor of good outcome (odds ratio, 6.8; P = .006).

Univariate analysis demonstrated the following significant predictors of good outcomes: pretreatment ASPECTS greater than 4 (P = .0043), younger age (P = .01), lower pretreatment NIHSS (P = .04), shorter time from groin puncture to discontinuation of aspiration (P = .0004), and revascularization time (P = .0001).

In a prepared statement, Dr. Frei noted that although thousands of men and women suffer a stroke every day, "only a small percentage of those affected are treated with endovascular therapy. This study strongly suggests that a simple ASPECTS reading from a fast, easy-to-obtain CTA source image can guide patient selection for endovascular therapy, particularly those most likely to benefit from the Penumbra System" beyond the 3- to 4.5-hour window.

The START trial was sponsored by Penumbra Inc.

Dr. Frei said that he had no relevant financial disclosures to make.