Decompressive bifrontal craniectomy provides a statistical advantage over medical treatment of intractable posttraumatic cerebral hypertension and should be considered in the management of malignant posttraumatic cerebral swelling. If the operation can be accomplished before the ICP value exceeds 40 torr for a sustained period and within 48 hours of the time of injury, the potential to influence outcome is greatest.

Hydrocephalus seems to have a multifactorial etiology. Knowledge of risk factors related to the occurrence of hydrocephalus may help guide neurosurgeons in the long-term care of patients who have experienced aneurysmal SAH.

Adhesion molecules are known to be involved in white cell adherence to the endothelium and subsequent diapedesis and migration in which a role in initiation of tissue damage is postulated. The authors have demonstrated the elevation of three adhesion molecules, with severely elevated levels of E-selectin seen in patients who later develop vasospasm. A correlation with a role of vascular adhesion molecules in the pathogenesis of cerebral vasospasm is suggested.

Background and Purpose-Inflammatory responses have been implicated in the elaboration of several forms of central nervous system injury, including cerebral vasospasm after subarachnoid hemorrhage (SAH). A critical event participating in such responses is the recruitment of circulating leukocytes into the inflammatory site. Two of the key adhesion molecules responsible for the attachment of leukocytes to endothelial cells are intercellular adhesion molecule-1 (ICAM-1) and the common ␤ chain of the integrin superfamily (CD18). This study examined the effects of monoclonal antibodies on ICAM-1 and the effects of CD18 on cerebral vasospasm after SAH. Methods-A rabbit model of SAH was utilized to test the influence of intracisternally administered antibodies to ICAM-1 and CD18 on cerebral vasospasm. Antibodies were administered alone or in combination, and the cross-sectional area of basilar arteries was assessed histologically on day 2 post-SAH. Results-Treatment with antibodies to ICAM-1 or CD18 inhibited vasospasm by 22% and 27%, respectively. When administered together, the attenuation of vasospasm increased to 56%. All of these effects achieved statistical significance. Conclusions-These findings provide the first evidence that the severity of cerebral vasospasm can be attenuated using monoclonal antibodies against ICAM-1 and CD18. The results reinforce the concept that cell-mediated inflammation plays an important role in cerebral vasospasm after SAH and suggest that therapeutic targeting of cellular adhesion molecules can be of benefit in treating cerebral vasospasm.

Transluminal cerebral angioplasty is very effective in reversing angiographically confirmed vasospasm, and anecdotal reports of its clinical utility are numerous. However, in this report the authors conclude that its superiority to medical management for symptomatic cerebral vasospasm is questionable.

OBJECTIVE To integrate spatial three-dimensional information concerning the pyramidal tracts into a customized system for frameless neuronavigation during brain tumor surgery. METHODS Four consecutive patients with intracranial tumors in eloquent areas underwent diffusion-weighted and anatomic magnetic resonance imaging studies within 48 hours before surgery. Diffusion-weighted datasets were merged with anatomic data for navigation purposes. The pyramidal tracts were segmented and reconstructed for three-dimensional visualization. The reconstruction results, together with the fused-image dataset, were available during surgery in the environment of a customized neuronavigation system. RESULTS In all four patients, the combination of reconstructed data and fused images was a helpful additional source of information concerning the tumor seat and topographical interaction with the pyramidal tract. In two patients, intraoperative motor cortex stimulation verified the tumor seat with regard to the precentral gyrus. CONCLUSION Diffusion-weighted magnetic resonance imaging allows individual estimation of large fiber tracts applicable as important information in intraoperative neuronavigation and in planning brain tumor resection. A three-dimensional representation of fibers associated with the pyramidal tract during brain tumor surgery is feasible with the presented technique and is a helpful adjunct for the neurosurgeon. The main drawbacks include the length of time required for the segmentation procedure, the lack of direct intraoperative control of the pyramidal tract position, and brain shift. However, mapping of large fiber tracts and its intraoperative use for neuronavigation have the potential to increase the safety of neurosurgical procedures and to reduce surgical morbidity.

The nonoperative management of patients with Types II and III fractures of the odontoid process consists of a prolonged course of cervical immobilization. The need for rigid fixation, demonstrated by the routine use of the halo vest in many institutions, has never been rigorously substantiated. We retrospectively analyzed our results with the nonsurgical management of odontoid fractures to ascertain whether cranial fixation affected overall outcome. Fifty-four patients managed at the University of Virginia Health Sciences Center, Charlottesville, VA, between 1976 and 1994 were studied. All 18 patients with Type III fractures (5 treated in the collar, 18 in the halo vest) demonstrated fracture healing and late stability. Among 36 individuals with Type II fractures, 20 were treated in the halo vest and 16 were managed in the Philadelphia collar or similar orthoses. The overall rate of late surgical intervention, the stability to flexion and extension, and the rate of bony fracture healing were not statistically different between the methods of immobilization. The rate of bony union was not significantly higher in the halo vest group (74 versus 53%), even though patients managed in the Philadelphia collar were significantly older than those in the halo vest (mean, 68 versus 44 yr). In general, nonsurgical management of Type III odontoid fractures was recommended, accompanied by use of a cervical orthosis. The determination of operative versus nonoperative treatment for Type II fractures was made on the basis of fracture anatomy, patient age, other associated injuries, and patient preference. The lack of a significant difference in the need for late surgical procedures or late instability, improved patient comfort with the cervical orthosis, and elimination of the risk of halo-related complications favored the use of the rigid cervical orthosis in the majority of these cases.

Although isolated series documenting clinical successes have prompted the increased use of papaverine as a treatment for vasospasm after SAH, this series suggests that, as it is currently being used, the drug does not provide added benefits, compared with medical treatment of vasospasm alone. This result does not preclude the possibility that alterations in the timing of or indications for drug treatment might produce beneficial effects.