First-bite syndrome: a novel complication of carotid body paraganglioma resection

Alyssa Trenery,1 Zaina P. Qureshi, PhD, MPH,2,3 Randall Rowen, PharmD,2 Terry Day, MD,4,5 LeAnn Norris, PharmD,2 and Charles L. Bennett, MD, PhD, MPP2,3,4
1 College of Arts and Sciences, University of South Carolina, Columbia, SC; 2 The South Carolina Center of Economic Excellence for Medication Safety, South Carolina College of Pharmacy, Columbia, SC; 3 Health Services, Policy and Management, Arnold School of Public Health, University of South Carolina, Columbia, SC; 4 Hollings Cancer Center of the Medical University of South Carolina, Charleston, SC; and 5 Head and Neck Tumor Center, Medical University of South Carolina, Charleston, SC

First-bite syndrome is a relatively uncommon and recently identified problem associated with surgery involving the parotid gland, neck tumors, parapharyngeal- space masses, and paragangliomas. Treatments for first-bite syndrome offer variable results, with botulinum toxin being perhaps the most promising option.

Case presentation
A 55-year-old man was referred for excision of an asymptomatic left parapharyngeal mass thought to be a carotid body paraganglioma. The patient had been treated previously with antibiotics for a possible sinus infection, without resolution. He underwent CT and angiographic embolization of the tumor prior to excision of the mass. Pretreatment imaging was consistent with a carotid body tumor. The patient was presented with treatment options, including surgical resection.

Preoperatively, the surgeon informed the patient of the potential for neurologic and cranial nerverelated complications and other perioperative risks. Surgery was performed via a transcervical incision. Through careful subadventitial dissection, the tumor was separated from the carotid artery and the carotid artery bifurcation. Excision of the tumor involved separation from and/or mobilization of the marginal mandibular branch of the facial nerve, hypoglossal nerve, spinal accessory nerve, glossopharyngeal nerve, and vagus nerve but was free of the sympathetic trunk and ganglion. However, the tumor was attached to and required ligation of the external carotid artery.

A few days after surgery, the patient experienced pain in his left jaw and ear immediately upon ingesting the first bite of solid food. The sensation was described as a “strong electrical jolt” with severe cramping, which was initially painful but then slowly dissipated after 5–15 minutes. In addition, the patient reported that the pain returned a few minutes after eating and persisted for up to 15 minutes.

About 2 weeks after surgery, the postprandial pain began to diminish in intensity, with complete resolution about 3 weeks thereafter. The first-bite syndrome pain, however, continued with similar intensity and duration 3.5 months post surgery. Selftreatment with acetaminophen and ibuprofen did not eliminate the pain.

Background discussion
First-bite syndrome is a relatively uncommon and recently identified problem associated with surgeries involving the parotid gland and/or the parapharyngeal space.1 The current description of the syndrome was initially reported in 1998 by Netterville,2 and the term “first-bite” syndrome was thought to be an appropriate name for the findings. In 1986, a gastrointestinal surgeon, Haubrich, had associated “first-bite syndrome” with a different clinical syndrome: esophageal dysfunction in patients who complained of an inability to swallow the first few bites of a meal ac companied by retrosternal pain. These individuals’ symptoms were relieved by regurgitation. 3

The true incidence of “first-bite syndrome” as characterized by Netterville is unknown, but cases have been reported after surgery of the parotid gland, neck tumors, parapharyngeal-space masses, and paragangliomas (Table 1).4–7 Those with the syndrome typically develop an intense, sharp, and sometimes cramping pain in the ipsilateral parotid region after the first bite of each meal.3 The severe pain lessens with each subsequent bite of the meal only to return at the first bite of the next meal.2

Netterville et al2 proposed that firstbite syndrome is due to the loss of sympathetic innervation to the parotid gland, resulting in the denervation and supersensitivity of the sympathetic receptors that control the myoepithelial cells. The pain comes from a supramaximal response of the myoepithelial cells stimulated by parasympathetic neurotransmitters, causing a spasm with the initial intake of food after a period of salivary rest (Figure 1). This etiology holds true in the majority of cases, although not all. A common feature for those afflicted with first-bite syndrome is residual parotid gland tissue. In some cases, even the thought of eating may cause a reaction by the salivary glands.

Tumors of the parapharyngeal space are rare; they typically evade diagnosis until found incidentally on imaging for another reason or grow to a size that becomes symptomatic or deforming. Imaging should be performed to evaluate the extent of the mass in the parapharyngeal area and the surrounding vascular structures preoperatively and to assure appropriate surgical planning and patient advisement.1 Biopsy is not recommended for carotid body tumors due to the risk of vascular injury, bleeding, and more severe complications.

Common surgical procedures that a b can result in first-bite syndrome include parotidectomy, neck dissection, transcervical excision of a sympathetic chain schwannoma, paraganglioma excision, and excision of a deep lobe parotid pleomorphic adenoma.8 In a retrospective study by Kawashima et al,4 9 of 22 patients who underwent surgery to remove a tumor in the parapharyngeal space postoperatively developed first-bite syndrome. All five patients who had external carotid artery ligation and resection of the deep lobe in the parotid gland during surgery developed first-bite syndrome. One patient underwent ligation of the external carotid artery from the sympathetic pathway and ligation of the auriculotemporal nerve from the parasympathetic pathway (Figure 1) and did not develop first-bite syndrome.

Therapy options
Treatments for first-bite syndrome offer variable results. Treatment outcomes experienced by patients in the various studies focusing on first-bite and Horner’s syndromes are summarized in Table 2, with only a few therapies having reported positive effects. Concomitant amitriptyline (25 mg at bedtime) reduced the intensity as well as the duration of pain, as reported by Phillips and Farquhar-Smith.9 In the cases from Chiu et al,8 two of three patients with first-bite syndrome found slight pain relief following tympanic neurectomy. Another patient found that amitriptyline and carbamazepine reduced the pain to only the first few bites.9 Casserly et al1 reported on a patient with Horner’s syndrome and first-bite syndrome whose pain improved with pregabalin (Lyrica).

Perhaps the most promising treatment is botulinum toxin. In a study by Ali et al,5 a woman who received no benefit from multiple narcotics and surgeries received an injection of botulinum toxin into the side of the parotid gland, where the pain was most intense. Four months after undergoing tympanic neurectomy (to relieve the symptoms of four surgical resections including mandibular osteotomies and parapharyngeal-space dissection), the patient received an injection of 75 units of botulinum toxin diluted in 2 mL of saline solution into the right parotid gland. Less than 48 hours later, the patient reported that the pain was markedly improved.5 If untreated, the pain associated with first-bite syndrome goes; it has been reported to resolve gradually, up to 21 months following its original onset.

Conclusion
The potential for first-bite syndrome should be included in the preoperative discussion for those undergoing surgery of the parotid gland, neck, and/or parapharyngeal space. Patients who undergo external carotid artery ligation as part of these surgeries or who develop Horner’s syndrome postoperatively appear to be at highest risk for development of firstbite syndrome. Additional reports on the efficacy of botulinum toxin in alleviating the pain associated with firstbite syndrome are eagerly awaited.

Disclosures
The authors have no conflicts of interest to disclose. Funding was provided by the University of South Carolina and the South Carolina Center of Economic Excellence Center for Medication Safety initiative (C.L.B.).

References
1. Casserly P, Kiely P, Fenton JE. Cervical sympathetic chain schwannoma masquerading as a carotid body tumour with a postoperative complication of first-bite syndrome. Eur Arch Otorhinolaryngol 2009;266:1659–1662.

 2. Netterville JL, Jackson CG, Miller FR, Wanamaker JR, Glasscock ME. Vagal paraganglioma: a review of 46 patients treated during a 20-year period. Arch Otolaryngol Head Neck Surg 1998;124:1133–1140.

 3. Haubrich WS. The first-bite syndrome. Henry Ford Hosp Med J 1986;34:275–278.

 4. Kawashima Y, Sumi T, Sugimoto T, Kishimoto S. First-bite syndrome: a review of 29 patients with parapharyngeal space tumor. Auris Nasus Larynx 2008;35:109–113.

 5. Ali MJ, Orloff LA, Lustig LR, Eisele DW. Botulinum toxin in the treatment of first bite syndrome. Otolaryngol Head Neck Surg 2008;139:742–743.

 6. Mandel L, Syrop SB. First-bite syndrome after parapharyngeal surgery for cervical schwannoma. J Am Dent Assoc 2008;139:1480– 1483.

 7. Albasri H, Eley KA, Saeed NR. Chronic pain related to first bite syndrome: report of two cases. Br J Oral Maxillofac Surg 2011;49:154–156.

 8. Chiu AG, Cohen JI, Burningham AR, Andersen PE, Davidson BJ. First bite syndrome: a complication of surgery involving the parapharyngeal space. Head Neck 2002;24:996–999.

 9. Phillips TJ, Farquhar-Smith WP. Pharmacological treatment of a patient with firstbite syndrome. Anaesthesia 2009;64:97–98.

Alyssa Trenery,1 Zaina P. Qureshi, PhD, MPH,2,3 Randall Rowen, PharmD,2 Terry Day, MD,4,5 LeAnn Norris, PharmD,2 and Charles L. Bennett, MD, PhD, MPP2,3,4
1 College of Arts and Sciences, University of South Carolina, Columbia, SC; 2 The South Carolina Center of Economic Excellence for Medication Safety, South Carolina College of Pharmacy, Columbia, SC; 3 Health Services, Policy and Management, Arnold School of Public Health, University of South Carolina, Columbia, SC; 4 Hollings Cancer Center of the Medical University of South Carolina, Charleston, SC; and 5 Head and Neck Tumor Center, Medical University of South Carolina, Charleston, SC

First-bite syndrome is a relatively uncommon and recently identified problem associated with surgery involving the parotid gland, neck tumors, parapharyngeal- space masses, and paragangliomas. Treatments for first-bite syndrome offer variable results, with botulinum toxin being perhaps the most promising option.

Case presentation
A 55-year-old man was referred for excision of an asymptomatic left parapharyngeal mass thought to be a carotid body paraganglioma. The patient had been treated previously with antibiotics for a possible sinus infection, without resolution. He underwent CT and angiographic embolization of the tumor prior to excision of the mass. Pretreatment imaging was consistent with a carotid body tumor. The patient was presented with treatment options, including surgical resection.

Preoperatively, the surgeon informed the patient of the potential for neurologic and cranial nerverelated complications and other perioperative risks. Surgery was performed via a transcervical incision. Through careful subadventitial dissection, the tumor was separated from the carotid artery and the carotid artery bifurcation. Excision of the tumor involved separation from and/or mobilization of the marginal mandibular branch of the facial nerve, hypoglossal nerve, spinal accessory nerve, glossopharyngeal nerve, and vagus nerve but was free of the sympathetic trunk and ganglion. However, the tumor was attached to and required ligation of the external carotid artery.

A few days after surgery, the patient experienced pain in his left jaw and ear immediately upon ingesting the first bite of solid food. The sensation was described as a “strong electrical jolt” with severe cramping, which was initially painful but then slowly dissipated after 5–15 minutes. In addition, the patient reported that the pain returned a few minutes after eating and persisted for up to 15 minutes.

About 2 weeks after surgery, the postprandial pain began to diminish in intensity, with complete resolution about 3 weeks thereafter. The first-bite syndrome pain, however, continued with similar intensity and duration 3.5 months post surgery. Selftreatment with acetaminophen and ibuprofen did not eliminate the pain.

Background discussion
First-bite syndrome is a relatively uncommon and recently identified problem associated with surgeries involving the parotid gland and/or the parapharyngeal space.1 The current description of the syndrome was initially reported in 1998 by Netterville,2 and the term “first-bite” syndrome was thought to be an appropriate name for the findings. In 1986, a gastrointestinal surgeon, Haubrich, had associated “first-bite syndrome” with a different clinical syndrome: esophageal dysfunction in patients who complained of an inability to swallow the first few bites of a meal ac companied by retrosternal pain. These individuals’ symptoms were relieved by regurgitation. 3

The true incidence of “first-bite syndrome” as characterized by Netterville is unknown, but cases have been reported after surgery of the parotid gland, neck tumors, parapharyngeal-space masses, and paragangliomas (Table 1).4–7 Those with the syndrome typically develop an intense, sharp, and sometimes cramping pain in the ipsilateral parotid region after the first bite of each meal.3 The severe pain lessens with each subsequent bite of the meal only to return at the first bite of the next meal.2

Netterville et al2 proposed that firstbite syndrome is due to the loss of sympathetic innervation to the parotid gland, resulting in the denervation and supersensitivity of the sympathetic receptors that control the myoepithelial cells. The pain comes from a supramaximal response of the myoepithelial cells stimulated by parasympathetic neurotransmitters, causing a spasm with the initial intake of food after a period of salivary rest (Figure 1). This etiology holds true in the majority of cases, although not all. A common feature for those afflicted with first-bite syndrome is residual parotid gland tissue. In some cases, even the thought of eating may cause a reaction by the salivary glands.

Tumors of the parapharyngeal space are rare; they typically evade diagnosis until found incidentally on imaging for another reason or grow to a size that becomes symptomatic or deforming. Imaging should be performed to evaluate the extent of the mass in the parapharyngeal area and the surrounding vascular structures preoperatively and to assure appropriate surgical planning and patient advisement.1 Biopsy is not recommended for carotid body tumors due to the risk of vascular injury, bleeding, and more severe complications.

Common surgical procedures that a b can result in first-bite syndrome include parotidectomy, neck dissection, transcervical excision of a sympathetic chain schwannoma, paraganglioma excision, and excision of a deep lobe parotid pleomorphic adenoma.8 In a retrospective study by Kawashima et al,4 9 of 22 patients who underwent surgery to remove a tumor in the parapharyngeal space postoperatively developed first-bite syndrome. All five patients who had external carotid artery ligation and resection of the deep lobe in the parotid gland during surgery developed first-bite syndrome. One patient underwent ligation of the external carotid artery from the sympathetic pathway and ligation of the auriculotemporal nerve from the parasympathetic pathway (Figure 1) and did not develop first-bite syndrome.

Therapy options
Treatments for first-bite syndrome offer variable results. Treatment outcomes experienced by patients in the various studies focusing on first-bite and Horner’s syndromes are summarized in Table 2, with only a few therapies having reported positive effects. Concomitant amitriptyline (25 mg at bedtime) reduced the intensity as well as the duration of pain, as reported by Phillips and Farquhar-Smith.9 In the cases from Chiu et al,8 two of three patients with first-bite syndrome found slight pain relief following tympanic neurectomy. Another patient found that amitriptyline and carbamazepine reduced the pain to only the first few bites.9 Casserly et al1 reported on a patient with Horner’s syndrome and first-bite syndrome whose pain improved with pregabalin (Lyrica).

Perhaps the most promising treatment is botulinum toxin. In a study by Ali et al,5 a woman who received no benefit from multiple narcotics and surgeries received an injection of botulinum toxin into the side of the parotid gland, where the pain was most intense. Four months after undergoing tympanic neurectomy (to relieve the symptoms of four surgical resections including mandibular osteotomies and parapharyngeal-space dissection), the patient received an injection of 75 units of botulinum toxin diluted in 2 mL of saline solution into the right parotid gland. Less than 48 hours later, the patient reported that the pain was markedly improved.5 If untreated, the pain associated with first-bite syndrome goes; it has been reported to resolve gradually, up to 21 months following its original onset.

Conclusion
The potential for first-bite syndrome should be included in the preoperative discussion for those undergoing surgery of the parotid gland, neck, and/or parapharyngeal space. Patients who undergo external carotid artery ligation as part of these surgeries or who develop Horner’s syndrome postoperatively appear to be at highest risk for development of firstbite syndrome. Additional reports on the efficacy of botulinum toxin in alleviating the pain associated with firstbite syndrome are eagerly awaited.

Disclosures
The authors have no conflicts of interest to disclose. Funding was provided by the University of South Carolina and the South Carolina Center of Economic Excellence Center for Medication Safety initiative (C.L.B.).

References
1. Casserly P, Kiely P, Fenton JE. Cervical sympathetic chain schwannoma masquerading as a carotid body tumour with a postoperative complication of first-bite syndrome. Eur Arch Otorhinolaryngol 2009;266:1659–1662.

 2. Netterville JL, Jackson CG, Miller FR, Wanamaker JR, Glasscock ME. Vagal paraganglioma: a review of 46 patients treated during a 20-year period. Arch Otolaryngol Head Neck Surg 1998;124:1133–1140.

 3. Haubrich WS. The first-bite syndrome. Henry Ford Hosp Med J 1986;34:275–278.

 4. Kawashima Y, Sumi T, Sugimoto T, Kishimoto S. First-bite syndrome: a review of 29 patients with parapharyngeal space tumor. Auris Nasus Larynx 2008;35:109–113.

 5. Ali MJ, Orloff LA, Lustig LR, Eisele DW. Botulinum toxin in the treatment of first bite syndrome. Otolaryngol Head Neck Surg 2008;139:742–743.

 6. Mandel L, Syrop SB. First-bite syndrome after parapharyngeal surgery for cervical schwannoma. J Am Dent Assoc 2008;139:1480– 1483.

 7. Albasri H, Eley KA, Saeed NR. Chronic pain related to first bite syndrome: report of two cases. Br J Oral Maxillofac Surg 2011;49:154–156.

 8. Chiu AG, Cohen JI, Burningham AR, Andersen PE, Davidson BJ. First bite syndrome: a complication of surgery involving the parapharyngeal space. Head Neck 2002;24:996–999.

 9. Phillips TJ, Farquhar-Smith WP. Pharmacological treatment of a patient with firstbite syndrome. Anaesthesia 2009;64:97–98.

Alyssa Trenery,1 Zaina P. Qureshi, PhD, MPH,2,3 Randall Rowen, PharmD,2 Terry Day, MD,4,5 LeAnn Norris, PharmD,2 and Charles L. Bennett, MD, PhD, MPP2,3,4
1 College of Arts and Sciences, University of South Carolina, Columbia, SC; 2 The South Carolina Center of Economic Excellence for Medication Safety, South Carolina College of Pharmacy, Columbia, SC; 3 Health Services, Policy and Management, Arnold School of Public Health, University of South Carolina, Columbia, SC; 4 Hollings Cancer Center of the Medical University of South Carolina, Charleston, SC; and 5 Head and Neck Tumor Center, Medical University of South Carolina, Charleston, SC

First-bite syndrome is a relatively uncommon and recently identified problem associated with surgery involving the parotid gland, neck tumors, parapharyngeal- space masses, and paragangliomas. Treatments for first-bite syndrome offer variable results, with botulinum toxin being perhaps the most promising option.

Case presentation
A 55-year-old man was referred for excision of an asymptomatic left parapharyngeal mass thought to be a carotid body paraganglioma. The patient had been treated previously with antibiotics for a possible sinus infection, without resolution. He underwent CT and angiographic embolization of the tumor prior to excision of the mass. Pretreatment imaging was consistent with a carotid body tumor. The patient was presented with treatment options, including surgical resection.

Preoperatively, the surgeon informed the patient of the potential for neurologic and cranial nerverelated complications and other perioperative risks. Surgery was performed via a transcervical incision. Through careful subadventitial dissection, the tumor was separated from the carotid artery and the carotid artery bifurcation. Excision of the tumor involved separation from and/or mobilization of the marginal mandibular branch of the facial nerve, hypoglossal nerve, spinal accessory nerve, glossopharyngeal nerve, and vagus nerve but was free of the sympathetic trunk and ganglion. However, the tumor was attached to and required ligation of the external carotid artery.

A few days after surgery, the patient experienced pain in his left jaw and ear immediately upon ingesting the first bite of solid food. The sensation was described as a “strong electrical jolt” with severe cramping, which was initially painful but then slowly dissipated after 5–15 minutes. In addition, the patient reported that the pain returned a few minutes after eating and persisted for up to 15 minutes.

About 2 weeks after surgery, the postprandial pain began to diminish in intensity, with complete resolution about 3 weeks thereafter. The first-bite syndrome pain, however, continued with similar intensity and duration 3.5 months post surgery. Selftreatment with acetaminophen and ibuprofen did not eliminate the pain.

Background discussion
First-bite syndrome is a relatively uncommon and recently identified problem associated with surgeries involving the parotid gland and/or the parapharyngeal space.1 The current description of the syndrome was initially reported in 1998 by Netterville,2 and the term “first-bite” syndrome was thought to be an appropriate name for the findings. In 1986, a gastrointestinal surgeon, Haubrich, had associated “first-bite syndrome” with a different clinical syndrome: esophageal dysfunction in patients who complained of an inability to swallow the first few bites of a meal ac companied by retrosternal pain. These individuals’ symptoms were relieved by regurgitation. 3

The true incidence of “first-bite syndrome” as characterized by Netterville is unknown, but cases have been reported after surgery of the parotid gland, neck tumors, parapharyngeal-space masses, and paragangliomas (Table 1).4–7 Those with the syndrome typically develop an intense, sharp, and sometimes cramping pain in the ipsilateral parotid region after the first bite of each meal.3 The severe pain lessens with each subsequent bite of the meal only to return at the first bite of the next meal.2

Netterville et al2 proposed that firstbite syndrome is due to the loss of sympathetic innervation to the parotid gland, resulting in the denervation and supersensitivity of the sympathetic receptors that control the myoepithelial cells. The pain comes from a supramaximal response of the myoepithelial cells stimulated by parasympathetic neurotransmitters, causing a spasm with the initial intake of food after a period of salivary rest (Figure 1). This etiology holds true in the majority of cases, although not all. A common feature for those afflicted with first-bite syndrome is residual parotid gland tissue. In some cases, even the thought of eating may cause a reaction by the salivary glands.

Tumors of the parapharyngeal space are rare; they typically evade diagnosis until found incidentally on imaging for another reason or grow to a size that becomes symptomatic or deforming. Imaging should be performed to evaluate the extent of the mass in the parapharyngeal area and the surrounding vascular structures preoperatively and to assure appropriate surgical planning and patient advisement.1 Biopsy is not recommended for carotid body tumors due to the risk of vascular injury, bleeding, and more severe complications.

Common surgical procedures that a b can result in first-bite syndrome include parotidectomy, neck dissection, transcervical excision of a sympathetic chain schwannoma, paraganglioma excision, and excision of a deep lobe parotid pleomorphic adenoma.8 In a retrospective study by Kawashima et al,4 9 of 22 patients who underwent surgery to remove a tumor in the parapharyngeal space postoperatively developed first-bite syndrome. All five patients who had external carotid artery ligation and resection of the deep lobe in the parotid gland during surgery developed first-bite syndrome. One patient underwent ligation of the external carotid artery from the sympathetic pathway and ligation of the auriculotemporal nerve from the parasympathetic pathway (Figure 1) and did not develop first-bite syndrome.

Therapy options
Treatments for first-bite syndrome offer variable results. Treatment outcomes experienced by patients in the various studies focusing on first-bite and Horner’s syndromes are summarized in Table 2, with only a few therapies having reported positive effects. Concomitant amitriptyline (25 mg at bedtime) reduced the intensity as well as the duration of pain, as reported by Phillips and Farquhar-Smith.9 In the cases from Chiu et al,8 two of three patients with first-bite syndrome found slight pain relief following tympanic neurectomy. Another patient found that amitriptyline and carbamazepine reduced the pain to only the first few bites.9 Casserly et al1 reported on a patient with Horner’s syndrome and first-bite syndrome whose pain improved with pregabalin (Lyrica).

Perhaps the most promising treatment is botulinum toxin. In a study by Ali et al,5 a woman who received no benefit from multiple narcotics and surgeries received an injection of botulinum toxin into the side of the parotid gland, where the pain was most intense. Four months after undergoing tympanic neurectomy (to relieve the symptoms of four surgical resections including mandibular osteotomies and parapharyngeal-space dissection), the patient received an injection of 75 units of botulinum toxin diluted in 2 mL of saline solution into the right parotid gland. Less than 48 hours later, the patient reported that the pain was markedly improved.5 If untreated, the pain associated with first-bite syndrome goes; it has been reported to resolve gradually, up to 21 months following its original onset.

Conclusion
The potential for first-bite syndrome should be included in the preoperative discussion for those undergoing surgery of the parotid gland, neck, and/or parapharyngeal space. Patients who undergo external carotid artery ligation as part of these surgeries or who develop Horner’s syndrome postoperatively appear to be at highest risk for development of firstbite syndrome. Additional reports on the efficacy of botulinum toxin in alleviating the pain associated with firstbite syndrome are eagerly awaited.

Disclosures
The authors have no conflicts of interest to disclose. Funding was provided by the University of South Carolina and the South Carolina Center of Economic Excellence Center for Medication Safety initiative (C.L.B.).

References
1. Casserly P, Kiely P, Fenton JE. Cervical sympathetic chain schwannoma masquerading as a carotid body tumour with a postoperative complication of first-bite syndrome. Eur Arch Otorhinolaryngol 2009;266:1659–1662.

 2. Netterville JL, Jackson CG, Miller FR, Wanamaker JR, Glasscock ME. Vagal paraganglioma: a review of 46 patients treated during a 20-year period. Arch Otolaryngol Head Neck Surg 1998;124:1133–1140.

 3. Haubrich WS. The first-bite syndrome. Henry Ford Hosp Med J 1986;34:275–278.

 4. Kawashima Y, Sumi T, Sugimoto T, Kishimoto S. First-bite syndrome: a review of 29 patients with parapharyngeal space tumor. Auris Nasus Larynx 2008;35:109–113.

 5. Ali MJ, Orloff LA, Lustig LR, Eisele DW. Botulinum toxin in the treatment of first bite syndrome. Otolaryngol Head Neck Surg 2008;139:742–743.

 6. Mandel L, Syrop SB. First-bite syndrome after parapharyngeal surgery for cervical schwannoma. J Am Dent Assoc 2008;139:1480– 1483.

 7. Albasri H, Eley KA, Saeed NR. Chronic pain related to first bite syndrome: report of two cases. Br J Oral Maxillofac Surg 2011;49:154–156.

 8. Chiu AG, Cohen JI, Burningham AR, Andersen PE, Davidson BJ. First bite syndrome: a complication of surgery involving the parapharyngeal space. Head Neck 2002;24:996–999.

 9. Phillips TJ, Farquhar-Smith WP. Pharmacological treatment of a patient with firstbite syndrome. Anaesthesia 2009;64:97–98.