✓ The temporal lobe, posterolateral cavernous sinus, tentorium, and petrous apex restrict anterolateral surgical access to lesions of the upper brain stem and clivus. The authors describe a modified transpetrosal approach that enhances the exposure of clival chordomas and aneurysms of the basilar artery bifurcation. An intradural and extradural subtemporal approach is combined with division of the tentorium and superior petrosal sinus, posterolateral dissection of the cavernous sinus, and intradural removal of the petrous bone from its apex to the cochlea. The indications, advantages, and disadvantages of this subtemporal, transcavernous, anterior transpetrosal approach are described in detail, along with its use in six patients.
Griffith R. Harsh IV and Laligam N. Sekhar
Griffith R. Harsh IV and Charles B. Wilson
✓ Local recurrence developed 6 years after the initial resection of an intraspinal meningeal tumor that originally was thought to be an angioblastic meningioma. Histological review of the pathology led to a change of that diagnosis to one of mesenchymal chondrosarcoma. The recurrent vascular tumor was embolized, then totally excised. Because this tumor had malignant features, the patient received irradiation and chemotherapy. No evidence of regrowth has been observed during a period of more than 4 years. Mesenchymal chondrosarcomas of the central nervous system and their treatment are reviewed.
Norman L. Lehman, Dikran S. Horoupian and Griffith R. Harsh IV
✓ The authors report the case of a 49-year-old man with synchronous drop metastases from a multiply recurrent somatotroph pituitary adenoma. The metastatic lesions were found in the subarachnoid space of the cauda equina and foramen magnum 18 years after the initial diagnosis of the disease. Five transsphenoidal resections had previously failed to cure the sellar tumor. Two of these, performed 4 and 5 years before the patient's current presentation, had been complicated by cerebrospinal fluid rhinorrhea that necessitated lumbar drainage. Resections of the two subarachnoid lesions, separated by 14 months, removed pathologically aggressive pituitary adenomas. There were no signs of local recurrence or subarachnoid dissemination of disease during the postoperative follow-up periods, which lasted 18 and 4 months, respectively. Previous cases of subarachnoid spread of a pituitary adenoma have been associated with multiple intracranial metastases, multiple intraspinal metastases, or widely disseminated disease. This case demonstrates that subarachnoid metastasis of a pituitary adenoma, particularly when it follows multiple operations, is not invariably widely disseminated or associated with a very poor prognosis.
Griffith R. Harsh IV, George W. Sypert, Philip R. Weinstein, Donald A. Ross and Charles B. Wilson
✓ Ossification of the posterior longitudinal ligament (OPLL) is a well-documented cause of cervical spine stenosis and myelopathy among Japanese patients. Reports of OPLL in North Americans are rare. Choices of diagnostic method and treatment for this entity remain controversial. The authors report the results of management of 20 patients in the United States with symptomatic OPLL of the cervical spine. These represented 10% to 20% of patients operated on over the last 3 years for myelopathy secondary to structural spinal compression. Most of these OPLL patients were Caucasian (60%), male (male:female 4:1), and middle-aged (median age 47.5 years). Six had previously undergone laminectomy or discectomy. Cervical roentgenograms and standard myelography occasionally suggested the diagnosis. Axial computerized tomography (CT) metrizamide myelography with small interslice intervals proved invaluable for diagnosis and operative planning. Magnetic resonance imaging was not necessary for diagnosis. Retrovertebral calcification extended over one to five bodies (mean 2.75). The mass ranged in size from 5 to 16 mm in anteroposterior diameter and reduced the residual canal diameter to a mean (± standard deviation) caliber of 9.42 ± 2.41 mm (mean narrowing ratio 0.44 ± 0.12).
Anterior cervical decompression by medial corpectomy and discectomy with fusion uniformly reduced preoperative myelopathy. Complications were limited to transient neurological deterioration in two patients, recurrent laryngeal nerve palsy in one, and halo device pin site infections in two. At a mean postoperative interval of 15 months, improvement was seen in each category of deficit: extremity weakness, hypesthesia, hypertonia, and urinary dysfunction. All fusions produced solid unions.
It is concluded that OPLL of the cervical spine is an unexpectedly prevalent cause of myelopathy among patients treated in the United States. Thin-section axial CT metrizamide myelography with small interslice intervals is essential for the investigation of patients who may have OPLL. Anterior decompression and stabilization by medial corpectomy, discectomy, removal of the calcified mass, and fusion is a safe and effective method of treatment.
Report of two cases
John S. Yu, M. Priscilla Short, James Schumacher, Paul H. Chapman and Griffith R. Harsh IV
✓ The authors describe two cases of intramedullary hemorrhage caused by thoracic hemangioblastoma. Both patients presented with acute paraplegia. The lesion in the first case was diagnosed by myelography and in the second by magnetic resonance imaging. Emergency surgical evacuation of the intramedullary hematoma and tumor was performed in these patients. Hemangioblastoma was confirmed by histopathological examination in both cases. Both patients remain paraplegic after 7 and 1 years, respectively. Intramedullary hemorrhage is a rare and devastating effect of spinal hemangioblastoma.
Griffith R. Harsh, Charles B. Wilson, Grant B. Hieshima and William P. Dillon
✓ A patient with trigeminal neuralgia and hemifacial spasm was evaluated using multiplanar magnetic resonance (MR) imaging with gadolinium enhancement. Preoperative images demonstrated massively ectatic vertebral and basilar arteries and their distortion of the brain stem and the trigeminal and facial nerves. Surgical manipulation included selective trigeminal rhizotomy, cushioning of the residual nerve at the point of maximal distortion by the underlying basilar artery, and microvascular decompression of the seventh nerve from the anterior inferior cerebellar artery which was being pushed dorsomedially by the vertebral artery. Postoperatively, the patient had neither trigeminal neuralgia nor facial spasm. Gadolinium-enhanced MR imaging not only excludes other etiologies such as tumor or arteriovenous malformation, but also demonstrates cranial nerve compression by ectatic vertebral and basilar arteries. The choice of preoperative imaging modality is discussed and the literature concerning the etiology of tic convulsif is reviewed.
Joshua B. Bederson, Griffith R. Harsh IV, John A. Walker and Charles B. Wilson
✓ The authors report a case in which bilateral cystic temporal lobe necrosis developed after treatment of nasopharyngeal lymphoepithelioma with 7000 cGy of external beam radiation. The patient presented with an isolated memory deficit that was documented by neuropsychological testing. After fenestration and internal shunting of both cysts, there was striking resolution of the lesions and of the memory deficit.
Anil K. Lalwani, Robert K. Jackler, Griffith R. Harsh IV and Fidelia Yuan-Shin Butt
✓ Irradiation of the central nervous system may cause significant morbidity, including endocrine dysfunction and intellectual impairment. The authors report a case of bilateral temporal bone encephaloceles in a 21-year-old man who had received prophylactic central nervous system irradiation for acute lymphocytic leukemia in early childhood. Endaural encephaloceles are uncommon, and most occur as a complication of mastoid surgery. The etiology, clinical features, radiological diagnosis, and surgical treatment of temporal bone encephaloceles are discussed.
Norman L. Lehman, Dikran S. Horoupian, Roger A. Warnke, Uma N. Sundram, Kendra Peterson and Griffith R. Harsh IV
✓ The authors report the case of a 63-year-old woman who presented with a primary dural extranodal marginal zone lymphoma (MZL) associated with massive kappa light chain amyloidosis of the meninges. Extranodal MZL is a low-grade B-cell lymphoma that may show variable degrees of plasmacytic differentiation. Like solitary plasmacytoma of soft tissue, which can also be associated with amyloid, extranodal MZL generally responds well to local therapy and has a good prognosis. It is important to distinguish these entities from high-grade primary central nervous system (CNS) B-cell lymphomas and more aggressive and/or widespread, potentially amyloidogenic conditions such as multiple myeloma, lymphoplasmacytoid lymphoma, and chronic lymphocytic leukemia/small lymphocytic lymphoma. To the authors' knowledge this is the first reported case of dural MZL associated with massive meningeal amyloid deposition. Extranodal MZL is a rare low-grade primary CNS B-cell lymphoma that may be associated with amyloidosis. It should be considered in the differential diagnosis of CNS lymphoproliferative lesions and CNS amyloidosis.