Two-handed endoscopic-directed vestibular nerve sectioning: case series and review of the literature.

OBJECT: Vestibular nerve sectioning is an accepted surgical treatment option for patients with medically refractory Ménière disease. In this paper the authors introduce and evaluate a 2-handed endoscopic-directed technique for vestibular nerve section. METHODS: Eleven patients underwent a retrosigmoid craniectomy for endoscopic-directed vestibular nerve sectioning as treatment for intractable vertigo associated with Ménière disease. In all patients, identification and dissection of the cranial nerve VII/VIII complex was performed entirely under endoscopic guidance. The authors used the specially designed Frazee II neuroendoscope, consisting of a traditional endoscope lens with a microsuction attachment. RESULTS: Vestibular nerve sectioning was completed in all 11 patients. Postoperative improvement in vertiginous episodes was achieved in 10 patients (91%). Auditory function was noted to be worse postoperatively in only 1 patient (9%). The same patient also developed a House-Brackmann Grade III facial nerve palsy, which improved gradually over time. There were no further complications, including no delayed CSF leaks. CONCLUSIONS: The endoscopic-directed approach represents a safe and effective method for performing vestibular nerve sectioning. Until now, the endoscope has been used primarily as an adjunct to the operating microscope in surgery at the cerebellopontine angle. In addition, previous endoscopic techniques typically require a third hand to manipulate the endoscope. With the 2-handed endoscopic-directed technique, however, the endoscope is used as the primary means of visualization, and the unique design of this endoscope allows for a bimanual procedure without the requirement of a cosurgeon. Advantages of using this technique compared with the microscope include superior brightness at close distances, greater depth of field, increased maneuverability within small regions, and an improved ability to visualize objects not in a direct line of sight. Among other things, this allows for minimally invasive openings, decreased cerebellar retraction, and better identification of nerve cleavage planes and vascular anatomy.

Intracranial Metastases of Cervical Intramedullary Low-Grade Astrocytoma without Malignant Transformation in Adult.

The first case of intracranial metastases of a cervical intramedullary low-grade astrocytoma without malignant transformation in adult is presented in this report. Seven years ago, a 45 year-old male patient underwent biopsy to confirm pathologic characteristics and received craniocervical radiation and chemotherapy for a grade II astrocytoma in the cervical spinal cord. Two years later, posterior fusion was necessary for progressive kyphosis in the cervical spine. He was well for approximately 7 years after the primary surgery. Two months ago, he presented with partial weakness and incoordination with gait difficulty. MRI Scan demonstrated multiple small lesions in the cerebellar vermis and left hemisphere. After suboccipital craniectomy and posterior cervical exposure, the small masses in the cerebellar vermis and hemispheres were excised to a large extent by guidance of an intraoperative navigation system. The tumor at the cervical and brain lesions was classified as an astrocytoma (WHO grade II). When a patient with low-grade astrocytoma in the spinal cord has new cranial symptoms after surgery, radiaton, and chemotherapy, the possibility of its metastasis should be suspected because it can spread to the intracranial cavity even without malignant transformation as shown in this case.

Nongalenic arteriovenous fistulas: history of treatment and technology.

Nongalenic cerebral arteriovenous fistulas (AVFs) are uncommon, high-flow vascular lesions first treated by Walter Dandy and his colleagues by using open surgery with ligation of the feeding artery. Due to advances in endovascular technology over the past four decades that make possible the control of high flow in AVFs, treatment has evolved from the sole option of surgery to include the alternative or adjunct option of endovascular embolization. The authors of this review discuss the history of nongalenic AVF treatment, including techniques of both surgery and interventional neuroradiology and the technological developments underlying them.

Primary intramedullary spinal cord germinoma: case report.

We describe an 18-year-old male with an intramedullary spinal cord germinoma in whom the diagnosis was made two years after onset of a progressive myelopathy. Spinal cord germinomas are rare, most having been described in young Japanese adults. They often respond well to radiotherapy. A unique feature of this case was the prolonged time interval between onset of the patient's symptoms and ability to visualize the mass radiographically. A further interesting finding was the infiltrative nature of the tumor surrounding residual spinal cord neurons.