Journal of neurosurgery
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Journal of neurosurgery · Feb 1984
Origin and evolution of plateau waves. Experimental observations and a theoretical model.
Laboratory observations made in cats with fluid-percussion head injuries have suggested that plateau waves or Lundberg "A-waves" are not independent of systemic circulatory events. Four distinct phases in the evolution of the plateau wave have been identified, and each related to a circulatory change in a causal manner. The first phase is the premonitory drift phase where intracranial pressure (ICP) gradually increases prior to the plateau proper. ⋯ The fourth phase is the resolution, characterized by a rapid decline in the ICP to baseline levels with stabilization of the SABP and CPP, and is best explained by autoregulatory vasoconstriction. Plateau waves appear to occur as the result of intact or mostly intact autoregulation responding to changes in CPP. The series of events that follow are best explained by what is known of normal autoregulation; the various properties of plateau waves are viewed and explained as the expected and logical consequences of an unstable CPP acting upon a generally intact cerebrovascular bed in the face of elevated ICP and decreased compliance.
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Journal of neurosurgery · Feb 1984
Case ReportsSubarachnoid hemorrhage from intracranial dissecting aneurysm.
Rupture of an intracranial dissecting aneurysm is a rare but dangerous event. The authors' experience with 14 cases of these lesions on the vertebrobasilar circulation suggests that these aneurysms have typical angiographic silhouettes and that, at least in the vertebral artery, they are treatable by proximal arterial occlusion.
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The recurrent arteries of Heubner were studied in 30 unfixed human brains (60 hemispheres) obtained from routine autopsies of individuals with a mean age of 34 years. The arteries were injected with tinted polyester resin via cannulation of the internal carotid arteries, and dissected under microscopic magnification. The recurrent artery of Heubner was absent in two hemispheres and double in seven hemispheres, either with a separate origin (in two) or from a common stem (in five). ⋯ The point of penetration of the main trunk was found to be constant at the level of the lateral perforated substance-medial Sylvian fissure in 85% of the cases. This report emphasizes the advantages of the intravascular casting resin injection technique in unfixed human brains over other conventional methods. It also describes the application of these anatomic data to the surgical strategy for the anterior circle of Willis, including the possible use of the recurrent artery of Heubner for microvascular reconstructive procedures.
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Journal of neurosurgery · Jan 1984
Brachytherapy of recurrent malignant brain tumors with removable high-activity iodine-125 sources.
Thirty-seven patients harboring recurrent malignant primary or metastatic brain tumors were treated by 40 implantations of high-activity iodine-125 (125I) sources. All patients had been treated with irradiation and most had been treated with chemotherapeutic agents, primarily nitrosoureas. Implantations were performed using computerized tomography (CT)-directed stereotaxy; 125I sources were held in one or more afterloaded catheters that were removed after the desired dose (minimum tumor dose of 3000 to 12,000 rads) had been delivered. ⋯ All improved after resection of the focal necrotic mass and are still alive 10, 15, 19, 24, and 25 months after the initial implantation procedure; only one patient has evidence of tumor regrowth. The median follow-up period after implantation for the malignant glioma (anaplastic astrocytoma and glioblastoma multiforme) group is 9 months, with 48% of patients still surviving. While direct comparison with the results of chemotherapy is difficult, results obtained in this patient group with interstitial brachytherapy are probably superior to results obtained with chemotherapy.
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Journal of neurosurgery · Jan 1984
Case ReportsCarotid to distal vertebral artery bypass for vertebrobasilar ischemia. Case report.
A simple technique is described for a venous graft between the common carotid artery and the extracranial vertebral artery. In the case described, the vertebral artery was shown angiographically to be occluded and reconstituted by collateral vessels. This patient had symptoms of vertebrobasilar insufficiency which resolved postoperatively.