Intradural jugular tubercle reduction to enhance exposure via the transcondylar approach: technical note

OBJECTIVE: The jugular tubercle can present an obstruction to adequate visualization of posteroinferior cerebellar artery (PICA) or vertebrobasilar junction aneurysms approached via a far lateral transcondylar approach. Reduction of the tubercle via an intradural approach was performed to enhance exposure. The technical details of this maneuver are discussed and demonstrated. METHODS: Two patients with PICA aneurysms were treated via the far lateral transcondylar approach. Intradural reduction of the jugular tubercle was performed to enhance exposure in each case. RESULTS: Exposure of the parent artery and aneurysm was enhanced in each case by intradural reduction of the jugular tubercle, providing several millimeters of added space. Both PICA aneurysms were successfully clipped with no intraoperative complications. CONCLUSION: Several millimeters of additional exposure can be obtained when treating a PICA or vertebrobasilar junction aneurysm via the far lateral transcondylar approach by removing the jugular tubercle via an intradural approach.     

远外侧枕下入路临床应用的初步经验

目的 改良远外侧枕下入路,适当显露病变,改善延髓和上颈髓腹侧病变的治疗效果。方法 采用远外侧枕下入路的5种改良入路,包括经小关节入路、经枕骨髁后入路、部分经枕骨髁入路、完全经枕骨髁入路和极端外侧经颈静脉孔入路,治疗延髓及上颈髓腹侧和腹外侧肿瘤12例、椎动脉动脉瘤2例,并分析手术治疗的效果和并发症。结果 本组12例肿瘤患者,7例肿瘤全切除,5例肿瘤在部分切除,所有患者术后恢复良好;其中3例术后遗留永久性组颅神经麻痹。2例动脉瘤患者,1例夹闭瘤颈,1例动脉瘤切除的患者因脑干缺血死亡。没有与入路有关的严重并发症。结论 远外侧枕下入路的改良可以满足延髓及上颈髓腹侧和腹外侧病变手术的需要和良好手术野显著,减少不必要的手术步骤,改善治疗效果。     

枕骨大孔区肿瘤的显微外科治疗

目的 探索枕骨大孔区肿瘤的治疗方法以提高治疗效果。方法 通过显微外科手术治疗31例枕骨大孔区肿瘤,其中脑膜瘤13例,神经鞘瘤15例,脊索3例。根据肿瘤附着点、生长方式及手术入路将肿瘤分为2种类型：I型：肿瘤主要位于枕骨大孔前方,包括基底起源于枕骨大孔上方、前方和前侧方,共15例;Ⅱ型：肿瘤主要位于枕骨大孔后方,包括基底起源于枕骨大孔后方、后侧方和椎管内,共16例。采用3种手术入路切除肿瘤：枕颈后正中和侧方入路18例,远外侧或经髁入路10例,枕下乙状窦后入路3例。结果 肿瘤全部切除25例,次全切除5例,部分切除1例,无手术死亡。I型枕骨大孔区肿瘤全切除9例,次全切除5例,部分切除1例;Ⅱ型均全切除。结论 I型枕骨大孔区肿瘤,手术全切除肿瘤困难,远外侧经髁入路是切除I型枕骨大孔区肿瘤最有效的方法;Ⅱ型肿瘤容易全切除,预后良好。     

The extreme lateral transcondylar approach to aneurysms of the vertebrobasilar junction, the vertebral artery, and the posterior inferior cerebellar artery

The unilateral suboccipital craniotomy is the commonly performed approach to aneurysms of the vertebrobasilar junction, the vertebral artery, and the posterior inferior cerebellar artery (PICA). Many of these aneurysms are placed anterior or anterolateral to the brain stem, necessitating brain stem retraction for adequate exposure. Small dorsolateral enlargement of the foramen magnum, partial resection of the occipital condyle, and removal of the jugular tubercle allow access to the neurovascular structures ventral to the medulla without retraction of the neuroaxis. This extreme lateral transcondylar approach was performed in 20 patients with aneurysms of the vertebrobasilar junction, the vertebral artery, and the PICA; intraoperatively, two suspected aneurysms proved to be vascular malformations. Occlusion of the aneurysm and vascular malformation was successfully performed in 16 patients, resection of the vascular malformation was achieved in 1 patient, and the vertebral artery was clipped in 3 patients with fusiform aneurysms without complications related to the extreme lateral transcondylar approach. Unobstructed exposure of the aneurysm, parent artery, and neural structures without retraction of the sensitive lower brain stem are the major advantages of the extreme lateral transcondylar approach.     

The dorsolateral, suboccipital, transcondylar approach to the lower clivus and anterior portion of the craniocervical junction.

The authors review their experience with a dorsolateral approach to the anterior rim of the foramen magnum and adjacent region. The operative technique includes exposure of the vertebral artery at C1, partial resection of the occipital condyle and lateral atlantal mass, and extradural drilling of the jugular tubercle. This approach has been applied in six patients who harbored intradural space-occupying lesions located ventral to the lower brain stem. Excision of the neoplasm was virtually total in all but one patient, in whom biopsy was the primary goal of the intervention. No morbidity and no mortality were associated with this approach. The main advantage of the dorsolateral, suboccipital, transcondylar route is the direct view it offers to the anterior rim of the foramen magnum without requiring brain stem retraction.     

The Extreme Lateral Transcondylar Approach to Aneurysms of the Vertebrobasilar Junction, the Vertebral Artery, and the Posterior Inferior Cerebellar Artery

The unilateral suboccipital craniotomy is the commonly performed approach to aneurysms of the vertebrobasilar junction, the vertebral artery, and the posterior inferior cerebellar artery (PICA). Many of these aneurysms are placed anterior or anterolateral to the brain stem, necessitating brain stem retraction for adequate exposure. Small dorsolateral enlargement of the foramen magnum, partial resection of the occipital condyle, and removal of the jugular tubercle allow access to the neurovascular structures ventral to the medulla without retraction of the neuroaxis. This extreme lateral transcondylar approach was performed in 20 patients with aneurysms of the vertebrobasilar junction, the vertebral artery, and the PICA; intraoperatively, two suspected aneurysms proved to be vascular malformations. Occlusion of the aneurysm and vascular malformation was successfully performed in 16 patients, resection of the vascular malformation was achieved in 1 patient, and the vertebral artery was clipped in 3 patients with fusiform aneurysms without complications related to the extreme lateral transcondylar approach. Unobstructed exposure of the aneurysm, parent artery, and neural structures without retraction of the sensitive lower brain stem are the major advantages of the extreme lateral transcondylar approach.     

Glossopharyngeal nerve schwannoma: report of a case operated on by the far-lateral transcondylar approach

Complete resection with conservation of cranial nerves is the primary goal of contemporary surgery for lower cranial nerve tumors. We describe the case of a patient with a schwannoma of the left glossopharyngeal nerve, operated on in our Neurosurgical Unit. The far lateral approach combined with laminectomy of the posterior arch of C1 was done in two steps. The procedure allowed total tumor resection and was found to be better than classic unilateral suboccipital or combined supra- and infratentorial approaches. The advantages and disadvantages of the far lateral transcondylar approach, compared to the other more common approaches, are discussed.     

Surgical experience with skull base approaches for foramen magnum meningioma

The surgical treatment of patients with foramen magnum meningioma remains challenging. This study evaluated the outcome of this tumor according to the evolution of surgical approaches during the last 29 years. A retrospective analysis of medical records, operative notes, and neuroimages of 492 meningioma cases from 1972 to 2001 identified seven cases of foramen magnum meningioma (1.4%). All patients showed various neurological symptoms corresponding with foramen magnum syndrome. The tumor locations were anterior in five cases and posterior in two. Surgical removal was performed through a transoral approach in one patient, the suboccipital approach in three, and the transcondylar approach in two. Total removal was achieved in all patients, except for one who refused any surgical treatment. The major complications were tetraparesis and lower cranial nerve paresis for tumors in anterior locations, and minor complications for posterior locations. One patient died of atelectasis and pneumonia after a long hospitalization. The transcondylar approach is recommended for anterior locations, and the standard suboccipital approach for posterior locations.     

C2 root nerve sheath tumors management

Background

Upper cervical nerve sheath tumors (NST) arising mainly from C2 root and to lesser extent from C1 root are not uncommon, they constitute approximately 5-12% of spinal nerve sheath tumors and 18-30% of all cervical nerve sheath tumors, unique in presentation and their relationship to neighbouring structures owing to the discrete anatomy at the upper cervical-craniovertebral region, and have atendency for growth reaching large-sized tumors before manifesting clinically due to the capacious spinal canal at this region; accordingly the surgical approaches to such tumors are modified. The aim of this paper is to discuss the surgical strategies for upper cervical nerve sheath tumors.

Methods

Eleven patients (8 male and 3 females), age range 28–63 years, with C2 root nerve sheath tumors were operated upon based on their anatomical relations to the spinal cord. The magnetic resonance imaging findings were utilized to determine the surgical approach. The tumors had extra- and intradural components in 10 patients, while in one the tumor was purely intradural. The operative approaches included varied from extreme lateral transcondylar approach(n?=?1) to laminectomy, whether complete(n?=?3) a or hemilaminectomy(n?=?7), with partial facetectomy(n?=?7), and with suboccipital craniectomy(n?=?2).

Results

The clinical picture ranged from spasticity (n?=?8, 72,72 %), tingling and numbness below neck (n?=?6, 54,54 %), weakness (n?=?6, 54,54 %), posterior column involvement (n?=?4, 26,36 %), and neck pain (n?=?4, 36,36 %). The duration of symptoms ranged from 1 to 54 months, total excision was performed in 7 patients; while in 3 patients an extraspinal component, and in 1 patient a small intradural component, were left in situ. Eight patients showed improvement of myelopathy; 2 patients maintained their grades. One poor-grade patient was deteriorated.

Conclusion

The surgical approaches for the C2 root nerve sheath tumors should be tailored according to the relationship to the spinal cord, determined by magnetic resonance imaging.     

Surgery on anterior foramen magnum meningiomas using a conventional posterior suboccipital approach: a report on an experience with 17 cases.

OBJECTIVE: The advantages of a posterior "conventional" suboccipital approach with a midline incision over lateral, anterolateral, and anterior approaches to anteriorly placed foramen magnum meningiomas are discussed. METHODS: From 1991 to March 2000, 17 patients with foramen magnum meningiomas arising from the anterior or anterolateral rim of the foramen magnum underwent operations in the Department of Neurosurgery at King Edward Memorial Hospital and Seth G.S. Medical College. All patients were operated on in a semi-sitting position by use of a conventional suboccipital approach with a midline incision and extension of the craniectomy laterally toward the side of the tumor up to the occipital condyle. RESULTS: The patients ranged in age from 17 to 72 years, and the tumors ranged in size from 2.1 to 3.8 cm. The intradural vertebral artery was at least partially encased on one side in eight patients and on both sides in two patients. The brainstem was displaced predominantly posteriorly in each patient. A partial condylar resection was performed in two cases to enhance the exposure. Total tumor resection was achieved in 14 patients, and a subtotal resection of the tumor was performed in the other 3 patients. In one patient, a small part of the tumor was missed inadvertently, and in the other two patients, part of the tumor in relation to the vertebral artery and posterior inferior cerebellar artery was deliberately left behind. After surgery, one patient developed exaggerated lower cranial nerve weakness. There was no significant postoperative complication in the remainder of the patients, and their conditions improved after surgery. The average length of follow-up is 43 months, and there has been no recurrence of the tumor or growth of the residual tumor. CONCLUSION: From our experience, we conclude that a large majority of anterior foramen magnum meningiomas can be excised with a lateral suboccipital approach and meticulous microsurgical techniques.     

Intradural jugular tuberclectomy in a case of inadequate extradural removal

BACKGROUND: The jugular tubercles are paired protuberances that arise from the inferolateral margins of the clivus and project posterosuperiorly over the hypoglossal canal. These bony structures sometimes obscure and hinder surgical manipulation of lesions situated in the lateral and premedullary cisterns during extended far lateral suboccipital approaches. The application of intradural jugular tuberclectomy is described to remove this bony eminence. METHODS: A case of ruptured dissecting aneurysm in the vertebral artery was treated through the transcondylar approach. Extradural removal of the posterior portion of the jugular tubercle was performed. The dura over the jugular tubercle was then removed, and the anterior part of the jugular tubercle was drilled away between the intradural hypoglossal canal foramen and jugular foramen under the lower cranial nerves. RESULTS: Great care was required during the intradural drilling procedure to prevent damage to the lower cranial nerves, brain stem, and jugular bulb. Intradural jugular tuberclectomy provided an adequate microscopic view of the midline anterior lower clival region. CONCLUSIONS: Intradural jugular tuberclectomy is a useful technique to remove the anterior part of this bony eminence after the transcondylar approach.     

Microvascular decompression for treatment of trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia: three surgical approach variations: technical note

OBJECTIVE: We have used three different approaches, namely, the infratentorial lateral supracerebellar approach, the lateral suboccipital infrafloccular approach, and the transcondylar fossa approach, for microvascular decompression for treatment of trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia, respectively. Each approach is a variation of the lateral suboccipital approach to the cerebellopontine angle (CPA); however, each has a different site of bony opening, a different surgical direction, and a different route along the cerebellar surface. METHODS: The infratentorial lateral supracerebellar approach is used to access the trigeminal nerve in the superior portion of the CPA through the lateral aspect of the cerebellar tentorial surface. The lateral suboccipital infrafloccular approach is directed through the inferior part of the cerebellar petrosal surface to reach the root exit zone of the facial nerve below the flocculus. The transcondylar fossa approach is used to access the glossopharyngeal nerve in the inferior portion of the CPA through the cerebellar suboccipital surface, after extradural removal of the jugular tubercle as necessary. RESULTS: In all three approaches, the cerebellar petrosal surface is never retracted transversely, that is, the cerebellar retraction is never directed parallel to the longitudinal axis of the VIIIth cranial nerve, dramatically reducing the risk of postoperative hearing loss. CONCLUSION: The greatest advantage of the differential selection of the surgical approach is increased ability to reach the destination in the CPA accurately, with minimal risk of postoperative cranial nerve palsy.     

椎管内髓外硬膜下多发性肿瘤的诊断与手术治疗

目的探讨椎管内多发性肿瘤的诊断及治疗方法。方法本组男11例,女4例。年龄16～81岁,（51.0±21.2）岁。病程2～27月,（11.0±7.6）月。均无皮肤咖啡斑及体表神经纤维瘤,头颅MR未见异常。增强MR示椎管内髓外硬膜下肿瘤46个,其中≥0.5cm肿瘤35个,肿瘤累及颈段1例,累及胸段5例,累及腰骶段12例。手术方法：采用后正中入路椎板切除术切除肿瘤,〈1cm者切除半椎板,在显微镜下操作,力争保留重要的载瘤神经而将肿瘤自神经上剔除,如肿瘤与神经无法分离,尽可能游离神经根在切除肿瘤后行神经根吻合。术后常规应用抗生素及激素治疗,术后戴颈围领、围腰保护2个月,同时训练腰背部肌肉。结果15例手术肿瘤全切12例,其中1例行神经根吻合;未全切的3例中2例术前诊断为多发神经纤维瘤或神经鞘瘤,因部位散在且直径〈0.5cm未考虑手术切除,另1例术中见肿瘤与多根神经根粘连,病理为转移瘤,仅行部分切除减压术。手术共切除肿瘤33个。病理：神经鞘瘤8例,神经纤维瘤1例,室管膜瘤2例,黑色素瘤1例,腺癌转移1例,脊膜瘤2例。黑色素瘤患者于术后22个月死亡,转移瘤患者于术后1年死亡,余13例随访4～72个月,平均30.1月,肿瘤无复发增长,其中2例多发神经鞘瘤未手术全切除者分别随访12、43个月,肿瘤无明显增长。13例存活者术后KPS评分较术前均有改善（术前75.4±13.3,术后最后一次随访时97.7±6.0,t=-7.366,P=0.000）。结论椎管内髓外硬膜下多发肿瘤以良性居多,中老年多见,半椎板及次全椎板入路显微手术切除是有效的治疗方法,〈0.5cm的无症状肿瘤可严密随访。     

Retrospective analysis of peripheral nerve sheath tumors of the second cervical nerve root in 60 surgically treated patients

OBJECT: This study is a retrospective analysis of 60 surgically treated patients with 64 peripheral nerve sheath tumors (PNSTs) at the second cervical (C-2) nerve root. The anatomical subtleties of these tumors and their implications for surgical strategy when compared with other spinal PNSTs and other tumors in the foramen magnum region are reviewed. METHODS: Sixty patients with C-2 PNSTs treated surgically in the Department of Neurosurgery at King Edward VII Memorial Hospital and Seth Gordhandas Sunderdas Medical College between 1992 and 2006 were studied. All patients underwent magnetic resonance imaging. Tumors were divided into 3 groups depending on their anatomical location identified during surgery. Those tumors located within or extending into the spinal dural tube were called Type A, those located within the dural tube of the C-2 ganglion were labeled as Type B, and tumors extending laterally into the paraspinal region were labeled as Type C. Follow-up durations ranged from 6 months to 15 years (mean 64 months). RESULTS: There were 38 male and 22 female patients in the study, who ranged in age from 6 to 62 years (mean 28 years). Nine patients had clinical features indicative of neurofibromatosis (NF). The mean duration of symptoms at the time of presentation was 27 months (range 4 days-5 years). Two patients had no specific symptoms related to the C-2 PNST, 6 patients had only local symptoms such as neck pain or stiffness, and 52 patients had symptoms of varying degrees of myelopathy. There were 5 solely Type A tumors, 7 Type A + B tumors, 31 Type B tumors, and 21 Type B + C tumors. All Type A, A + B, and B tumors were totally resected. Seven of 21 Type B + C tumors were partially resected, and the remainder were completely resected. All patients postoperatively reported varying improvement in their preoperative symptoms. Except for patients with NF who were disabled by other tumors, the rest of the patients resumed their normal life style. There have been no cases of symptomatic tumor recurrence. CONCLUSIONS: The majority of PNSTs located at the C-2 level in these patients probably arose from the large C-2 ganglion and are limited within the dural confines or are interdural in location. In contrast to other spinal PNSTs, the location of C-2 PNSTs is in most cases posterior to the lateral mass of the atlas and axis and the atlantoaxial joint and is exposed to the posterior without any bone cover. Radical tumor resection is safe, resolution of clinical symptoms is rapid, and recurrence rates are extremely low. In a selected number of cases, bone work for tumor exposure and resection can be entirely avoided.     

The midline suboccipital subtonsillar approach to the hypoglossal canal: surgical anatomy and clinical application

Summary Primary lesions of the hypoglossal canal, such as hypoglossal schwannomas, are rare. No consensus exists with regard to the surgical approach of choice for treatment of these lesions. Usually, lateral transcondylar approaches have been used. The authors describe the surgical anatomy of the midline subtonsillar approach to the hypoglossal canal. This approach includes a midline suboccipital craniotomy, dorsal opening of the foramen magnum and elevation of ipsilateral cerebellar tonsil to expose the hypoglossal nerve and its canal. The midline subtonsillar approach permits a straight primary intradural view to the hypoglossal canal. There is no necessity of condylar resections. The surgical anatomy of the subtonsillar approach is described and illustrated by an example of a case.     

Far-lateral approach to intradural lesions of the foramen magnum without resection of the occipital condyle

OBJECT: The goal of this study was to determine whether drilling out the occipital condyle facilitates surgery via the far-lateral approach by comparing data from 10 clinical cases with that from studies of eight cadaver heads. METHODS: During the last 6 years at Louisiana State University Health Sciences Center-Shreveport, 10 patients underwent surgery via the far-lateral approach to the foramen magnum. Six of these patients harbored anterior foramen magnum meningiomas, one patient a dermoid cyst, two patients vertebral artery (VA) aneurysms, and an additional patient suffered from rheumatoid disease of the craniocervical junction. The surgical approach consisted of retromastoid craniectomy and C-1 laminectomy. The seven tumors and the pannus of rheumatoid disease were completely excised, and the two aneurysms were clipped without drilling the occipital condyle. In one patient a chronic subdural hematoma was found 3 months after surgery, but no patient displayed any complication associated with surgery. It is significant that in no patient was a cerebrospinal fluid leak present. All patients experienced improved neurological function postoperatively. To compare surgical visibility, eight cadaveric specimens (16 sides) were studied, including delineation of the VA and its segments around the craniocervical junction. Increase in visibility as a function of fractional removal of the occipital condyle was quantified by measuring the degrees of visibility gained by removing one third and one half of the occipital condyle. Removal of one third of the occipital condyle produced a mean increase of 15.9 degrees visibility, and removal of one half produced a mean increase of 19.9 degrees. CONCLUSIONS: On the basis of their findings the authors conclude that removal of the occipital condyle is not necessary for the safe and complete resection of anterior intradural foramen magnum tumors.     

Combined microsurgical and endoscopic removal of extensive suprasellar and prepontine epidermoid tumors

Epidermoids tend to grow around and adhere to critical neurovascular structures, but total or maximal tumor removal is recommended to reduce the risk of recurrence. We describe our method of combined microscopic and endoscopic resection for extensive epidermoid tumors. Thirteen patients with epidermoid tumors located in the suprasellar, prepontine, or surrounding cisterns underwent microsurgical resection with a rigid endoscope and a high definition camera system. An anterior petrosal and/or a pterional approach was selected in 6 patients and a lateral suboccipital approach in 7 patients. An endoscope was used with the operating microscope to remove 6 tumors through the anterior petrosal and/or pterional approaches in 5 cases and the lateral suboccipital approach in 1 case. An endoscope was used to confirm microscopic removal in 5 patients. Total removal was achieved in 5 patients and subtotal removal in 8 patients. We recommend the combined microsurgical and endoscopic approaches to achieve maximal resection of extensive suprasellar and prepontine epidermoids.     

Osteoplastic lateral suboccipital approach for acoustic neuroma surgery

OBJECTIVE: Persistent headache remains a significant problem in a small group of patients after acoustic neuroma surgery via the lateral suboccipital approach. We describe a modified technique of osteoplastic lateral suboccipital craniotomy for surgery of the cerebellopontine angle. This simple and elegant technique provides a superior cosmetic result and a significant reduction in patients' symptoms. METHODS: We report on our series of 75 patients who underwent surgery for acoustic neuroma. The maximal follow-up period was 4 years. RESULTS: No patients reported headache postoperatively. Cerebrospinal fluid fistulae were not observed. CONCLUSION: This modified approach minimizes cerebellar retraction, and the neural and vascular structures can be preserved under direct visualization of the tumor. This lateral suboccipital approach is a useful modification of previous approaches in acoustic neuroma surgery. It provides successful tumor resection and excellent functional results.     

Occipitocervical fusion following the extreme lateral transcondylar approach

BACKGROUND: Modern cranial base approaches to the clivus and foramen magnum may threaten the stability of the cranio-cervical junction. This necessitates stabilization and fusion in some cases. We studied occipitocervical fusion after extreme lateral transcondylar approaches.METHODS: Twenty-seven patients underwent an extreme lateral transcondylar approach over a 2-year period. Two patients were excluded because of prior occipitocervical fusion. The pathological diagnosis was meningioma in ten patients, chordoma in six patients, neurofibroma in two, and 10 patients had other tumoral and nontumoral pathologies.RESULTS: Eight patients required occipitocervical fusion and stabilization. Five of six patients with chordomas required fusion, whereas no patient with a meningioma underwent fusion. All the patients who were fused had more than 70% resection of their occipital condyle. No patient with resection of less than 70% of the occipital condyle required fusion. Significant interference of the surgical construct with follow-up imaging was seen only in the patient in whom a stainless steel Steinman pin was used.CONCLUSION: One third of patients will require fusion after extreme lateral transcondylar approaches. Most patients with less than 70% resection of the condyle remain stable without need for surgical intervention, whereas complete resection necessitates fusion in most cases.     

Microvascular decompression for glossopharyngeal neuralgia: case report

We report the case of a glossopharyngeal neuralgia that was successfully treated using microvascular decompression (MVD). A 61-year-old female reported intermittent piercing pain from tongue to pinna on the left side. Although she had been prescribed carbamazepine and has undergone attempted nerve block on several occasions, no pain relief has been achieved. MVD was thus attempted using a lateral suboccipital approach. The offending vessel, which was PICA, had adhered to the glossopharyngeal nerve and was repositioned laterally away from the nerve by interposition of a felt cushion. Pain disappeared immediately after surgery and has not recurred. In the literature, MVD for glossopharyngeal neuralgia has been performed using a transcondylar approach to achieve minimally invasive surgery. However, the sensory distributions for the floor of the oral cavity and tongue involve 4 overlapping nerves: the trigeminal nerve, sensory components of the facial and vagal nerves, and the glossopharyngeal nerve. In typical cases, it seems that the transcondylar fossa approach is appropriate for glossopharyngeal neuralgia. If the pain occurs in the place involving an overlapping nerve, the lateral suboccipital approach might be necessary.