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.

Severe pain confounds neuropsychological test performance.

There is little information on the effect of pain on neuropsychological test performance. We have undertaken this study to explore which tests are affected by pain, the magnitude of these changes, and other confounders of neuropsychological performance in a population of patients having spine surgery. Twenty-four elderly English speaking Caucasian patients (age > 60 years) were enrolled pre-operatively in this Institutional Review Board approved study. Pain scores using an 11-point Numeric Pain Intensity scale and performance on a neuropsychological battery (Controlled Oral Word Association, Rey Complex Figure, Trails A and B) were assessed at two times, before and one day after surgery. Scores were calculated using the standard algorithms and change scores were calculated by subtracting the baseline from follow-up scores. After surgery, performance on the Rey Complex Figure ( r = -0.577, p = 0.004) and Trails Part A (r = 0.527, p = 0.01) declined with increasing post-operative pain scores. Women reported higher pain scores post-operatively than men (p = 0.046), and performed worse than men for change in performance on Trails Part A (p = 0.027). These data suggest that pain can influence performance on certain cognitive tests, and that some gender differences in these effects may occur. Interpretation of performance measures should take into account possible effects of pain, although our understanding of pain effects and ability to predict them in individual people, currently are quite limited.

Spinal cord swelling preceding syrinx development. Case report.

The pathophysiology of syrinx development is controversial. The authors report on a patient with progressive cervical myelopathy and a Chiari I malformation in whom spinal cord swelling preceded, by a few months, the development of a syrinx in the same location. The patient underwent a craniocervical decompressive procedure and duraplasty, and complete resolution of cord swelling and syringomyelia was achieved. This report is consistent with the theory that patients with Chiari I malformation have increased transmural flow of cerebrospinal fluid, which causes spinal cord swelling that later coalesces into a syrinx. The pathophysiology of syrinx development from spinal cord edema and the success of surgical decompressive treatments that do not invade the central nervous system support the prompt treatment of patients with spinal cord edema who are at risk for the development of a syrinx.

Estrogen and progesterone receptor-negative T11 vertebral hemangioma presenting as a postpartum compression fracture: case report and management.

OBJECTIVE AND IMPORTANCE: Pregnancy-related vertebral hemangioma compressive myelopathy is a rare occurrence that tends to arise in the upper thoracic and lower cervical spine, peaks during the third trimester, and remits after parturition. Whether corticosteroid receptors play a role in the pathogenesis of these lesions is unknown. Most of these lesions have been managed with posterior decompression. CLINICAL PRESENTATION: A 29-year-old woman presented with acute-onset lower-extremity weakness and sensory loss immediately after parturition. INTERVENTION: We used a retropleural approach for anterior decompression and fusion, followed by radiation therapy. Immunohistochemical analysis of estrogen and progesterone receptor expression was performed. CONCLUSION: We report an unusual case of lower thoracic postpartum vertebral hemangioma compressive myelopathy caused by a parturition-related compression fracture. Results of tests for corticosteroid receptors were negative, which implicated a hemodynamic rather than hormonal cause for disease progression.

Clinoid and paraclinoid aneurysms: surgical anatomy, operative techniques, and outcome.

BACKGROUND: Paraclinoid or ophthalmic segment aneurysms arise from the internal carotid artery (ICA) between the roof of the cavernous sinus and the origin of the posterior communicating artery. Clinoid aneurysms arise between the proximal and distal carotid dural rings. The complex anatomy of clinoid and paraclinoid ICA aneurysms often makes them difficult to treat by microsurgery. The natural history of these aneurysms varies, based on their location and anatomic relationships. Accurate preoperative assessment of the origin of these aneurysms is therefore a critical aspect of their management. METHODS: The authors reviewed 35 clinoid and paraclinoid ICA aneurysms operated in 28 patients and classify them according to their anatomic location and angiographic pattern. The operative techniques, surgical outcomes, and indications for surgery are reviewed. RESULTS: Based on surgical anatomy and angiographic patterns, the aneurysms were classified into two categories: clinoid segment and paraclinoid (ophthalmic) segment. The clinoid segment aneurysms consisted of medial, lateral and anterior varieties. The paraclinoid aneurysms could be classified topographically into medial, posterior and anterior varieties, or based on the artery of origin into ophthalmic, superior, hypophyseal, and posterior paraclinoid aneurysms. Ophthalmic aneurysms were most common (40%), followed by posterior ICA wall aneurysms (29%), superior hypophyseal aneurysms (14%), and clinoid aneurysms (17%). Twenty patients (71%) had single aneurysms. Of the remaining eight, six had bilateral aneurysms and two had unilateral multiple aneurysms. Of the 35 aneurysms, 32 were clipped satisfactorily, as confirmed by intraoperative or postoperative angiography. One small broad-based aneurysm was wrapped, and two others were treated by trapping and bypass techniques. Three patients who had bilateral aneurysms underwent successful clipping of four contralateral, left-sided aneurysms via a right frontotemporal, transorbital approach. On follow-up (mean, 39 months), 25 patients were in excellent condition (returned to their prior occupation), two were in good condition (independent, but not working), and one died postoperatively of vasospasm. CONCLUSION: Our increased knowledge of anatomy and refinements in operative techniques have greatly improved the surgical treatment of clinoid and paraclinoid aneurysms.

Epithelioid hemangioendothelioma of the lumbar vertebral column: case report and review of literature.

Epithelioid hemangioendothelioma is a recently described, rare vasoformative vascular tumor of variable biological behavior. Its principal sites of occurrence are soft tissues, liver, lung, and bone. There have been no formal case reports of this tumor occurring in the vertebral column, and there are no reports in the literature of surgical treatment for vertebral epithelioid hemangioendothelioma. We present a case of primary vertebral epithelioid hemangioendothelioma occurring in the L2 vertebral body. Surgical treatment, pathological findings, imaging characteristics, and a review of the literature are presented.

Diphtheria toxin mutant selectively kills cerebellar Purkinje neurons.

CRM107 (crossreacting material 107), a double point mutant of diphtheria toxin that lacks receptor-binding activity, specifically kills cerebellar Purkinje cells in vivo. After injection into guinea pig cerebrospinal fluid, CRM107 (0.9 micrograms) and CRM107-monoclonal antibody conjugates (10 micrograms) kill up to 90% of the total Purkinje cell population with no detectable toxicity to other neurons. Animals exhibit ataxia, tremor, and abnormalities of posture and tone. Native diphtheria toxin, ricin, and ricin A chain do not cause ataxia and do not reduce the Purkinje cell population after intrathecal injection into guinea pigs at toxic or maximally tolerated doses. However, in rats, which will tolerate higher doses of diphtheria toxin than guinea pigs, Purkinje cells can be killed by both CRM107 and diphtheria toxin. A truncated mutant of diphtheria toxin, called CRM45, can also cause Purkinje cell killing but has additional toxicity not seen with CRM107. Animals treated with intrathecal CRM107 or CRM107 linked to antibodies may serve as models for Purkinje cell loss in a broad spectrum of human diseases and may be used to further study cerebellar physiology. Understanding the basis for the Purkinje cell sensitivity to CRM107 may illuminate other causes of Purkinje cell loss.