Literature Monitor

Elevated blood ammonia levels may help differentiate epileptic generalized convulsive seizures (GCS) from other events, suggests a recent report in Epilepsia. When Rawan Albadareen and associates measured blood ammonia levels in 78 patients with GCS, psychogenic nonepileptic seizures with convulsions (PNES-C), or focal seizures using video–electroencephalography (vEEG) monitoring, they discovered that ammonia levels at or above 80 μmol/L could classify generalized convulsive seizures in 80% of patients with a sensitivity of 53.9% and specificity of 100%. Their findings suggest that transient hyperammonemia may serve as an inexpensive test for the diagnosis of GCS.

Albadareen R, Gronseth G, Landazuri P, et al. Postictal ammonia as a biomarker for electrographic convulsive seizures: a prospective study. Epilepsia. 2016;57(8): 1221-1227.

Elevated blood ammonia levels may help differentiate epileptic generalized convulsive seizures (GCS) from other events, suggests a recent report in Epilepsia. When Rawan Albadareen and associates measured blood ammonia levels in 78 patients with GCS, psychogenic nonepileptic seizures with convulsions (PNES-C), or focal seizures using video–electroencephalography (vEEG) monitoring, they discovered that ammonia levels at or above 80 μmol/L could classify generalized convulsive seizures in 80% of patients with a sensitivity of 53.9% and specificity of 100%. Their findings suggest that transient hyperammonemia may serve as an inexpensive test for the diagnosis of GCS.

Albadareen R, Gronseth G, Landazuri P, et al. Postictal ammonia as a biomarker for electrographic convulsive seizures: a prospective study. Epilepsia. 2016;57(8): 1221-1227.

Elevated blood ammonia levels may help differentiate epileptic generalized convulsive seizures (GCS) from other events, suggests a recent report in Epilepsia. When Rawan Albadareen and associates measured blood ammonia levels in 78 patients with GCS, psychogenic nonepileptic seizures with convulsions (PNES-C), or focal seizures using video–electroencephalography (vEEG) monitoring, they discovered that ammonia levels at or above 80 μmol/L could classify generalized convulsive seizures in 80% of patients with a sensitivity of 53.9% and specificity of 100%. Their findings suggest that transient hyperammonemia may serve as an inexpensive test for the diagnosis of GCS.

Albadareen R, Gronseth G, Landazuri P, et al. Postictal ammonia as a biomarker for electrographic convulsive seizures: a prospective study. Epilepsia. 2016;57(8): 1221-1227.

In order to determine if there is an association between ictal fear and other auras and with patients’ gender and age, investigators analyzed 536 participants in the Epilepsy Phenome/Genome Project.  Among 36 patients with confirmed ictal fear, the phenomenon was associated with temporal lobe auras, including cephalic, olfactory, and visceral symptoms, as well as déjà vu and derealization. Aphasias were also correlated with ictal fear but researchers found no link between such fear and age or gender.

Chong DJ, Dugan P; The EPGP Investigators. Ictal fear: associations with age, gender, and other experiential phenomena. Epilepsy Behav. 2016;62:153-158. 

In order to determine if there is an association between ictal fear and other auras and with patients’ gender and age, investigators analyzed 536 participants in the Epilepsy Phenome/Genome Project.  Among 36 patients with confirmed ictal fear, the phenomenon was associated with temporal lobe auras, including cephalic, olfactory, and visceral symptoms, as well as déjà vu and derealization. Aphasias were also correlated with ictal fear but researchers found no link between such fear and age or gender.

Chong DJ, Dugan P; The EPGP Investigators. Ictal fear: associations with age, gender, and other experiential phenomena. Epilepsy Behav. 2016;62:153-158. 

In order to determine if there is an association between ictal fear and other auras and with patients’ gender and age, investigators analyzed 536 participants in the Epilepsy Phenome/Genome Project.  Among 36 patients with confirmed ictal fear, the phenomenon was associated with temporal lobe auras, including cephalic, olfactory, and visceral symptoms, as well as déjà vu and derealization. Aphasias were also correlated with ictal fear but researchers found no link between such fear and age or gender.

Chong DJ, Dugan P; The EPGP Investigators. Ictal fear: associations with age, gender, and other experiential phenomena. Epilepsy Behav. 2016;62:153-158. 

Researchers examined 1567 patient medical records from the Vanderbilt University Medical Center Adult EMU and found a 5.2% prevalence rate of coexisting epilepsy/psychogenic nonepileptic spells (PNES). Other findings include:

·         Epileptic seizures were preceded by a PNES event in 94.4% of epilepsy/PNES patients

·         Patients with epilepsy/PNES had a higher presence of epilepsy risk factors

·         Abnormal brain MRI and abnormal neurological examination were more common in the epilepsy/PNES group. 

Chen-Block S, Abou-Khalil BW, Arain A, et al. Video-EEG results and clinical characteristics in patients with psychogenic nonepileptic spells: the effect of a coexistent epilepsy. Epilepsy Behav. 2016;62:62-65.

Researchers examined 1567 patient medical records from the Vanderbilt University Medical Center Adult EMU and found a 5.2% prevalence rate of coexisting epilepsy/psychogenic nonepileptic spells (PNES). Other findings include:

·         Epileptic seizures were preceded by a PNES event in 94.4% of epilepsy/PNES patients

·         Patients with epilepsy/PNES had a higher presence of epilepsy risk factors

·         Abnormal brain MRI and abnormal neurological examination were more common in the epilepsy/PNES group. 

Chen-Block S, Abou-Khalil BW, Arain A, et al. Video-EEG results and clinical characteristics in patients with psychogenic nonepileptic spells: the effect of a coexistent epilepsy. Epilepsy Behav. 2016;62:62-65.

Researchers examined 1567 patient medical records from the Vanderbilt University Medical Center Adult EMU and found a 5.2% prevalence rate of coexisting epilepsy/psychogenic nonepileptic spells (PNES). Other findings include:

·         Epileptic seizures were preceded by a PNES event in 94.4% of epilepsy/PNES patients

·         Patients with epilepsy/PNES had a higher presence of epilepsy risk factors

·         Abnormal brain MRI and abnormal neurological examination were more common in the epilepsy/PNES group. 

Chen-Block S, Abou-Khalil BW, Arain A, et al. Video-EEG results and clinical characteristics in patients with psychogenic nonepileptic spells: the effect of a coexistent epilepsy. Epilepsy Behav. 2016;62:62-65.

People with epilepsy are at an increased risk of specific safety-related adverse events while in the hospital. Researchers found that hospitalized patients with epilepsy were at a greater risk for fall with hip fracture, respiratory failure, sepsis, and preventable postoperative death. The authors also reported that adverse events were associated with a prolonged length of stay, as well as an increase in the odds of inpatient death and an increase in high-level post-acute care.

Mendizabal A, Thibault DP, Willis AW. Patient safety events in hospital care of individuals with epilepsy [published online ahead of print June 28, 2016]. Epilepsia. 2016;doi:10.1111/epi.13440.

People with epilepsy are at an increased risk of specific safety-related adverse events while in the hospital. Researchers found that hospitalized patients with epilepsy were at a greater risk for fall with hip fracture, respiratory failure, sepsis, and preventable postoperative death. The authors also reported that adverse events were associated with a prolonged length of stay, as well as an increase in the odds of inpatient death and an increase in high-level post-acute care.

Mendizabal A, Thibault DP, Willis AW. Patient safety events in hospital care of individuals with epilepsy [published online ahead of print June 28, 2016]. Epilepsia. 2016;doi:10.1111/epi.13440.

People with epilepsy are at an increased risk of specific safety-related adverse events while in the hospital. Researchers found that hospitalized patients with epilepsy were at a greater risk for fall with hip fracture, respiratory failure, sepsis, and preventable postoperative death. The authors also reported that adverse events were associated with a prolonged length of stay, as well as an increase in the odds of inpatient death and an increase in high-level post-acute care.

Mendizabal A, Thibault DP, Willis AW. Patient safety events in hospital care of individuals with epilepsy [published online ahead of print June 28, 2016]. Epilepsia. 2016;doi:10.1111/epi.13440.

In a study of 1816 patients with tuberous sclerosis complex (TSC), researchers found that specific disease manifestations—cardiac rhabodmyomas, retinal hemartomas, renal cysts, renal angiomyolipipomas, and facial angiofibromas—were associated with a higher likelihood of epilepsy development. The authors posit that this research can help identify patients who will benefit from novel, targeted, preventative treatments.

Jeong A, Wong M. Systemic disease manifestations associated with epilepsy in tuberous sclerosis complex [published online ahead of print July 15, 2016]. Epilepsia. 2016;doi:10.1111/epi.13467. 

In a study of 1816 patients with tuberous sclerosis complex (TSC), researchers found that specific disease manifestations—cardiac rhabodmyomas, retinal hemartomas, renal cysts, renal angiomyolipipomas, and facial angiofibromas—were associated with a higher likelihood of epilepsy development. The authors posit that this research can help identify patients who will benefit from novel, targeted, preventative treatments.

Jeong A, Wong M. Systemic disease manifestations associated with epilepsy in tuberous sclerosis complex [published online ahead of print July 15, 2016]. Epilepsia. 2016;doi:10.1111/epi.13467. 

In a study of 1816 patients with tuberous sclerosis complex (TSC), researchers found that specific disease manifestations—cardiac rhabodmyomas, retinal hemartomas, renal cysts, renal angiomyolipipomas, and facial angiofibromas—were associated with a higher likelihood of epilepsy development. The authors posit that this research can help identify patients who will benefit from novel, targeted, preventative treatments.

Jeong A, Wong M. Systemic disease manifestations associated with epilepsy in tuberous sclerosis complex [published online ahead of print July 15, 2016]. Epilepsia. 2016;doi:10.1111/epi.13467. 

To determine if patients with epilepsy are appropriate candidates for resective surgery, presurgical conferences are conducted to review magnetic resonance images (MRIs) of the patient’s head. Kenney and associates analyzed repeat reviews of MRIs at presurgical epilepsy conferences to assess their impact on the decision-making process. Among the 233 patients whose charts were re-reviewed, 94 patients (40.3%) had the resective surgery performed, and the analysis revealed that 41 patients (17.6%) had previously undiagnosed findings; 18 of the 41 patients had the surgery. However, among 4 of the 41 patients (9.8%), the re-reviews found abnormalities that did not warrant surgical resection, including autoimmunity and bilateral pathology.  

Kenney DL, Kelly-Williams KM, Krecke KN et al. Usefulness of Repeat Review of Head Magnetic Resonance Images During Presurgical Epilepsy Conferences. Epilepsy Res. 2016. In press.  http://dx.doi.org/10.1016/j.eplepsyres.2016.06.005.

To determine if patients with epilepsy are appropriate candidates for resective surgery, presurgical conferences are conducted to review magnetic resonance images (MRIs) of the patient’s head. Kenney and associates analyzed repeat reviews of MRIs at presurgical epilepsy conferences to assess their impact on the decision-making process. Among the 233 patients whose charts were re-reviewed, 94 patients (40.3%) had the resective surgery performed, and the analysis revealed that 41 patients (17.6%) had previously undiagnosed findings; 18 of the 41 patients had the surgery. However, among 4 of the 41 patients (9.8%), the re-reviews found abnormalities that did not warrant surgical resection, including autoimmunity and bilateral pathology.  

Kenney DL, Kelly-Williams KM, Krecke KN et al. Usefulness of Repeat Review of Head Magnetic Resonance Images During Presurgical Epilepsy Conferences. Epilepsy Res. 2016. In press.  http://dx.doi.org/10.1016/j.eplepsyres.2016.06.005.

To determine if patients with epilepsy are appropriate candidates for resective surgery, presurgical conferences are conducted to review magnetic resonance images (MRIs) of the patient’s head. Kenney and associates analyzed repeat reviews of MRIs at presurgical epilepsy conferences to assess their impact on the decision-making process. Among the 233 patients whose charts were re-reviewed, 94 patients (40.3%) had the resective surgery performed, and the analysis revealed that 41 patients (17.6%) had previously undiagnosed findings; 18 of the 41 patients had the surgery. However, among 4 of the 41 patients (9.8%), the re-reviews found abnormalities that did not warrant surgical resection, including autoimmunity and bilateral pathology.  

Kenney DL, Kelly-Williams KM, Krecke KN et al. Usefulness of Repeat Review of Head Magnetic Resonance Images During Presurgical Epilepsy Conferences. Epilepsy Res. 2016. In press.  http://dx.doi.org/10.1016/j.eplepsyres.2016.06.005.

Before surgeons perform a resection involving the language-dominant hemisphere of a patient with epilepsy, they may do electrical stimulation mapping to identify a patient’s language-dominant hemisphere. Typically they will ask patients to identify objects to help locate the language cortex and then avoid resection in an area of the brain in which electrical stimulation makes it difficult for patients to name said objects. But because word production involves mechanisms that may be centered in more than one area of the brain, Hamberger et al tested locations that have been identified by stimulation as naming sites to look for disparities. Testing patients with refractory temporal lobe epilepsy who had subdural electrodes implanted, they discovered that stimulating naming sites in the superior temporary lobe was more likely to disrupt phonological processing but did not affect a patient’s ability to process semantic information. Stimulating the inferior temporal naming sites was more likely to impair semantic processing. 

Hamberger MJ, Miozzo M, Schevon CA, et al. Functional differences among stimulation-identified cortical naming sites in the temporal region. Epilepsy Behav. 2016;60:124-129. 

Before surgeons perform a resection involving the language-dominant hemisphere of a patient with epilepsy, they may do electrical stimulation mapping to identify a patient’s language-dominant hemisphere. Typically they will ask patients to identify objects to help locate the language cortex and then avoid resection in an area of the brain in which electrical stimulation makes it difficult for patients to name said objects. But because word production involves mechanisms that may be centered in more than one area of the brain, Hamberger et al tested locations that have been identified by stimulation as naming sites to look for disparities. Testing patients with refractory temporal lobe epilepsy who had subdural electrodes implanted, they discovered that stimulating naming sites in the superior temporary lobe was more likely to disrupt phonological processing but did not affect a patient’s ability to process semantic information. Stimulating the inferior temporal naming sites was more likely to impair semantic processing. 

Hamberger MJ, Miozzo M, Schevon CA, et al. Functional differences among stimulation-identified cortical naming sites in the temporal region. Epilepsy Behav. 2016;60:124-129. 

Before surgeons perform a resection involving the language-dominant hemisphere of a patient with epilepsy, they may do electrical stimulation mapping to identify a patient’s language-dominant hemisphere. Typically they will ask patients to identify objects to help locate the language cortex and then avoid resection in an area of the brain in which electrical stimulation makes it difficult for patients to name said objects. But because word production involves mechanisms that may be centered in more than one area of the brain, Hamberger et al tested locations that have been identified by stimulation as naming sites to look for disparities. Testing patients with refractory temporal lobe epilepsy who had subdural electrodes implanted, they discovered that stimulating naming sites in the superior temporary lobe was more likely to disrupt phonological processing but did not affect a patient’s ability to process semantic information. Stimulating the inferior temporal naming sites was more likely to impair semantic processing. 

Hamberger MJ, Miozzo M, Schevon CA, et al. Functional differences among stimulation-identified cortical naming sites in the temporal region. Epilepsy Behav. 2016;60:124-129. 

Open surgical resection is still considered the best approach for patients with epilepsy that do not respond well to medical therapy. But despite being considered the gold standard in neurosurgical care, the shortcomings of open surgical resection need to be addressed. McGovern and colleagues do so in a review published in Current Neurology and Neuroscience Reports. They point to the value of stereotactic electroencephalography, which can localize deep epileptic foci. Similarly laser interstitial thermal therapy (LITT) and stereotactic radiosurgery have advantages because they can ablate specific regions of the brain using minimally or non-invasive techniques. In the case of LITT, it can offer clinicians near real-time feedback on its effects. Neurostimulation is also worth consideration in select patients because it can reduce seizure occurrence without the need for ablation or resection

McGovern RA, Banks GP, McKhann GM 2nd. New techniques and progress in epilepsy surgery. Curr Neurol Neurosci Rep. 2016;16(7):65. 

Open surgical resection is still considered the best approach for patients with epilepsy that do not respond well to medical therapy. But despite being considered the gold standard in neurosurgical care, the shortcomings of open surgical resection need to be addressed. McGovern and colleagues do so in a review published in Current Neurology and Neuroscience Reports. They point to the value of stereotactic electroencephalography, which can localize deep epileptic foci. Similarly laser interstitial thermal therapy (LITT) and stereotactic radiosurgery have advantages because they can ablate specific regions of the brain using minimally or non-invasive techniques. In the case of LITT, it can offer clinicians near real-time feedback on its effects. Neurostimulation is also worth consideration in select patients because it can reduce seizure occurrence without the need for ablation or resection

McGovern RA, Banks GP, McKhann GM 2nd. New techniques and progress in epilepsy surgery. Curr Neurol Neurosci Rep. 2016;16(7):65. 

Open surgical resection is still considered the best approach for patients with epilepsy that do not respond well to medical therapy. But despite being considered the gold standard in neurosurgical care, the shortcomings of open surgical resection need to be addressed. McGovern and colleagues do so in a review published in Current Neurology and Neuroscience Reports. They point to the value of stereotactic electroencephalography, which can localize deep epileptic foci. Similarly laser interstitial thermal therapy (LITT) and stereotactic radiosurgery have advantages because they can ablate specific regions of the brain using minimally or non-invasive techniques. In the case of LITT, it can offer clinicians near real-time feedback on its effects. Neurostimulation is also worth consideration in select patients because it can reduce seizure occurrence without the need for ablation or resection

McGovern RA, Banks GP, McKhann GM 2nd. New techniques and progress in epilepsy surgery. Curr Neurol Neurosci Rep. 2016;16(7):65. 

To determine if genetic variation influences the susceptibility to traumatic brain injury and the subsequent posttraumatic seizures, Anne Ritter and her associates from the University of Pittsburgh analyzed the relationship between posttraumatic seizures and single nucleotide polymorphisms (SNPs). Thirty two SNPs were evaluated within SLC1A1 and SLC1A6, which are protein coding genes for glutamate transporters. (Glutamate transporters control glutamate levels and excitatory neurotransmission and have been associated with traumatic brain injury.) The analysis found that among 253 individuals, 49 had experienced posttraumatic seizures. Within this smaller group, they found genotypes at SNP rs10974620 (SLC1A1) linked to the time to the first seizure during a three year follow-up. And after factoring in several confounding variables, rs10974620 remained statistically significant (P = .017).

Rittner AC, Kammerer CM, Brooks MM, Conley YP, Wagner AM. Genetic variation in neuronal glutamate transport genes and associations with posttraumatic seizure. Epilepsia. 2016;57(6):984-993. 

To determine if genetic variation influences the susceptibility to traumatic brain injury and the subsequent posttraumatic seizures, Anne Ritter and her associates from the University of Pittsburgh analyzed the relationship between posttraumatic seizures and single nucleotide polymorphisms (SNPs). Thirty two SNPs were evaluated within SLC1A1 and SLC1A6, which are protein coding genes for glutamate transporters. (Glutamate transporters control glutamate levels and excitatory neurotransmission and have been associated with traumatic brain injury.) The analysis found that among 253 individuals, 49 had experienced posttraumatic seizures. Within this smaller group, they found genotypes at SNP rs10974620 (SLC1A1) linked to the time to the first seizure during a three year follow-up. And after factoring in several confounding variables, rs10974620 remained statistically significant (P = .017).

Rittner AC, Kammerer CM, Brooks MM, Conley YP, Wagner AM. Genetic variation in neuronal glutamate transport genes and associations with posttraumatic seizure. Epilepsia. 2016;57(6):984-993. 

To determine if genetic variation influences the susceptibility to traumatic brain injury and the subsequent posttraumatic seizures, Anne Ritter and her associates from the University of Pittsburgh analyzed the relationship between posttraumatic seizures and single nucleotide polymorphisms (SNPs). Thirty two SNPs were evaluated within SLC1A1 and SLC1A6, which are protein coding genes for glutamate transporters. (Glutamate transporters control glutamate levels and excitatory neurotransmission and have been associated with traumatic brain injury.) The analysis found that among 253 individuals, 49 had experienced posttraumatic seizures. Within this smaller group, they found genotypes at SNP rs10974620 (SLC1A1) linked to the time to the first seizure during a three year follow-up. And after factoring in several confounding variables, rs10974620 remained statistically significant (P = .017).

Rittner AC, Kammerer CM, Brooks MM, Conley YP, Wagner AM. Genetic variation in neuronal glutamate transport genes and associations with posttraumatic seizure. Epilepsia. 2016;57(6):984-993. 

To determine the unique characteristics of cluster seizures, investigators looked at 92 subjects, 83% of whom had at least one seizure cluster. They found that seizures occurring within a cluster were significantly shorter than the last seizure that occurred in the cluster. They also discovered that the terminal seizure in a cluster is similar to duration in isolated seizures that are not part of a cluster. Finally, the researchers found that cluster seizures are more likely to occur in the frontal and temporal lobes.

Ferastraoaru V, Schulze-Bonhage A, Lipton RB, Dumpelmann M, Legatt AD, Hunt SR. Termination of seizure clusters is related to duration of focal seizures. Epilepsia. 2016;57(6):889-895.

To determine the unique characteristics of cluster seizures, investigators looked at 92 subjects, 83% of whom had at least one seizure cluster. They found that seizures occurring within a cluster were significantly shorter than the last seizure that occurred in the cluster. They also discovered that the terminal seizure in a cluster is similar to duration in isolated seizures that are not part of a cluster. Finally, the researchers found that cluster seizures are more likely to occur in the frontal and temporal lobes.

Ferastraoaru V, Schulze-Bonhage A, Lipton RB, Dumpelmann M, Legatt AD, Hunt SR. Termination of seizure clusters is related to duration of focal seizures. Epilepsia. 2016;57(6):889-895.

To determine the unique characteristics of cluster seizures, investigators looked at 92 subjects, 83% of whom had at least one seizure cluster. They found that seizures occurring within a cluster were significantly shorter than the last seizure that occurred in the cluster. They also discovered that the terminal seizure in a cluster is similar to duration in isolated seizures that are not part of a cluster. Finally, the researchers found that cluster seizures are more likely to occur in the frontal and temporal lobes.

Ferastraoaru V, Schulze-Bonhage A, Lipton RB, Dumpelmann M, Legatt AD, Hunt SR. Termination of seizure clusters is related to duration of focal seizures. Epilepsia. 2016;57(6):889-895.