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OBJECTIVEThe objective of this study was to determine the utility and safety of rigid endoscopy as an adjunct during posterior fossa surgery to treat cranial neuropathies.METHODSA suboccipital craniotomy was performed for 19 patients with non-neoplastic processes involving the Vth, VIIth, and/or VIIIth cranial nerves. Ten patients with trigeminal neuralgia (n = 8), hemifacial spasm (n = 1), or intractable tinnitus (n = 1) underwent primarily microvascular decompression procedures. One patient with geniculate neuralgia underwent nervus intermedius sectioning combined with microvascular decompression. Eight patients underwent unilateral vestibular nerve neurectomies for treatment of Ménière's disease. A 0- or 30-degree rigid endoscope was used in conjunction with the standard microscopic approach for all procedures.RESULTSAll patients experienced resolution or significant improvement of their preoperative symptoms after posterior fossa surgery. The endoscope allowed improved definition of anatomic neurovascular relationships without the need for significant cerebellar or brainstem retraction. Cleavage planes between the cochlear and vestibular nerves entering the internal auditory canal and sites of vascular compression could not be microscopically observed for several patients; however, endoscopic identification was possible for all patients. There were no complications related to the use of the endoscope.CONCLUSIONThe rigid endoscope can be used safely during posterior fossa surgery to treat cranial neuropathies, and it allows improved observation of the cranial nerves, nerve cleavage planes, and vascular anatomic features without significant cerebellar or brainstem retraction.

OBJECTIVEOur goals were to study the normal histological features of the jugular foramen, compare them with the histopathological features of glomus tumors involving the temporal bone, and thus provide insight into the surgical management of these tumors with respect to cranial nerve function.METHODSTen jugular foramen blocks were obtained from five human cadavers after removal of the brain. Microscopic studies of these blocks were performed, with particular attention to fibrous or bony compartmentalization of the jugular foramen, the relationships of the caudal cranial nerves to the jugular bulb/jugular vein and internal carotid artery, and the fascicular structures of the nerves. In addition, we studied the histopathological features of 11 glomus tumors involving the temporal bone (10 patients), with respect to nerve invasion, associated fibrosis, and carotid artery adventitial invasion.RESULTSA dural septum separating the IXth cranial nerve from the fascicles of Cranial Nerves X and XI, at the intracranial opening, was noted. Only two specimens, however, had a septum (one bony and one fibrous) producing internal compartmentalization of the jugular foramen. The cranial nerves remained fasciculated within the foramen, with the vagus nerve containing multiple fascicles and the glossopharyngeal and accessory nerves containing one and two fascicles, respectively. All of these nerve fascicles lay medial to the superior jugular bulb, with the IXth cranial nerve located anteriorly and the XIth cranial nerve posteriorly. All nerve fascicles had separate connective tissue sheaths. A dense connective tissue sheath was always present between the IXth cranial nerve and the internal carotid artery, at the level of the carotid canal. The inferior petrosal sinus was present between the IXth and Xth cranial nerves, as single or multiple venous channels. The glomus tumors infiltrated between the cranial nerve fascicles and inside the perineurium. They also produced reactive fibrosis. In one patient, in whom the internal carotid artery was also excised, the tumor invaded the adventitia.CONCLUSIONWithin the jugular foramen, the cranial nerves lie anteromedial to the jugular bulb and maintain a multifascicular histoarchitecture (particularly the Xth cranial nerve). Glomus tumors of the temporal bone can invade the cranial nerve fascicles, and infiltration of these nerves can occur despite normal function. In these situations, total resection may not be possible without sacrifice of these nerves.

THE MANAGEMENT OF chordomas and chondrosarcomas involving the cranial base remains controversial. The options for therapy include biopsy, partial resection, radical resection, and various forms of radiotherapy. In this article, we analyze the outcome of 60 patients with cranial base chordoma

Background Tumors at the craniovertebral junction are difficult to remove because of their location and complex anatomic relations. The lateral transcondylar approach is a versatile approach to this area and allows access to a variety of intra- and extradural tumors. The lateral transcondylar approach has been used for a series of chordomas in this location. Objective The nuances of this operation and its effectiveness in this group of patients are presented. Methods There were 29 chordomas (1991-2007) in this region treated by one of the authors (CS) that were retrospectively reviewed. The imaging studies and medical records were evaluated. The location and extent of the tumor were defined, and the postoperative images were studied to determine the degree of resection. Results There were 11 male and 18 female patients; their age range was 7 to 67 years. Headache and neck pain were the predominant presenting symptoms, and hypoglossal nerve palsy was the most common cranial nerve palsy. Twelve patients had previous surgery and 9 had previous radiation. Anterior midline and lateral approaches were used independently or in combination to treat these patients. Dural invasion was found in 27 patients requiring resection of the dura. Surgery was performed in 1 stage in 19 patients, and the tumor resection in the remaining patients was done in 2 stages. The lateral transcondylar approach was used in 19 patients. The occipital condyle was involved in all these patients. Radical tumor resection was achieved in 17 patients. Patients who had complete removal of the occipital condyle required occipitocervical fusion (20 patients) in the immediate postoperative period. Conclusion The lateral transcondylar approach is an effective approach to chordomas in this region. Most of the tumors were large and extended into multiple anatomic compartments. The approach allowed resection of all the involved tissues, intra- and extracranial, and afforded excellent neurovascular control.

The authors report a series of 30 patients who underwent reconstruction of the internal carotid artery (ICA) at the skull base with the saphenous vein during the surgical management of lesions at the cranial base. This group represents about 9% of the total patients in whom the ICA in the cavernous or petrous segment was manipulated either during the surgical approach or dissection from the tumor. Two of these patients failed a clinical balloon test occlusion of the ICA, and, in 9 patients, cerebral blood flow during balloon test occlusion dropped to between 15 to 30 ml/100g/min. The patency rate is 86% over a mean follow-up time of 18 months. Of the 4 patients with graft occlusion, 3 were asymptomatic. The fourth patient who suffered ICA dissection with graft occlusion subsequently died from a massive cerebral infarction. Three patients with inadequate collateral circulation sustained minor strokes as the result of the temporary ICA occlusion during the grafting, but all are capable of leading independent lives. Two patients suffered acute graft occlusion within 12 hours of the surgery and underwent successful revision of the graft. None of the grafted patients suffered delayed occlusion or ischemic or embolic problems. The patients with malignant tumors died within 2 years of the operation from the original disease; total tumor removal was accomplished in 14 of the 19 patients with benign tumors. The aneurysms were successfully eliminated in all 5 patients. The lessons learned from this experience are discussed.

OBJECTIVE: Patients with partial or complete bilateral vertebral artery occlusion often present with signs and symptoms of transient ischemic attacks or infarction. Advances in phase contrast magnetic resonance imaging have led to noninvasive assessment of volumetric blood flow rates and direction that help in the workup and management of these patients. CLINICAL PRESENTATION: We present the case of a patient with symptoms of vertebrobasilar insufficiency without previous transient ischemic attacks or stroke. Quantitative magnetic resonance angiography (QMRA) demonstrated bilateral vertebral artery occlusion with reversal of flow in the basilar and vertebral arteries to the level of the posterior inferior cerebellar arteries bilaterally. A prominent right posterior communicating artery filled the basilar artery and proximal vertebral arteries. INTERVENTION: The presence of reversal and diminished flow in the basilar and vertebral arteries suggested that occipital artery-to-posterior inferior cerebellar artery bypass would improve posterior circulation, relieve symptoms, and reduce the risk of infarction. Postoperative QMRA and angiography confirmed revascularization, and QMRA confirmed correction of blood flow direction. CONCLUSION: This case illustrates the potential of QMRA as part of a comprehensive cerebrovascular assessment, operative planning, and follow-up of patients with vertebrobasilar insufficiency.

Extradural tumors of the cervical spine may involve the vertebral artery on one or both sides, posing one of the limiting factors toward the radical resection of such neoplasms. A standard anterior approach may be inadequate for the management of such tumors. An anterolateral approach allows the dissection and mobilization of the vessel, which can then be preserved, resected, or reconstructed with a vein graft. An anterior approach can be supplemented with this for tumor resection and stabilization. This management strategy is described in 10 patients with a variety of tumors.

The aesthetic and functional morbidity associated with facial palsy is significant. Fortunately, corneal exposure and ulceration with the potential for the loss of visual acuity can be minimized by eyelid procedures such as gold weight implantation and horizontal eyelid shortening. Although primarily designed for restoration of eyelid function, these procedures also improve ocular cosmesis. However, uncertainty remains regarding the indications for eyelid surgery: When should surgery be performed, in whom, and which procedure(s)? On the basis of our series of 60 patients evaluated for facial paralysis, guidelines for the management of the paralyzed eyelids after iatrogenic injury to the facial nerve are proposed.