Journal of neurosurgery
-
Journal of neurosurgery · May 1984
Serial measurement of regional cerebral blood flow in patients with SAH using 133Xe inhalation and emission computerized tomography.
A noninvasive three-dimensional method for measuring cerebral blood flow (CBF), xenon-133 inhalation and emission computerized tomography, was used to investigate the CBF changes accompanying delayed neurological deterioration following subarachnoid hemorrhage (SAH). A total of 67 measurements were performed on 20 patients in Hunt and Hess' clinical Grades I to III in the first 21 days post SAH. ⋯ Severe vasospasm was noted in three of these patients in whom arteriography was performed in the 2nd week post SAH. Diffuse bihemispheric CBF decreases were noted later in the course of delayed neurological deficits; however, measurements obtained soon after the onset of focal symptoms suggest that the only CBF decreases directly produced by vasospasm in Grade III patients are regional changes.
-
The spinal canals of 11 patients with various pathological conditions, both benign and malignant, were examined intraoperatively using real-time ultrasonography. The spinal cords in eight of these patients with lesions causing cord compression were seen to oscillate rhythmically over each mass with a frequency corresponding to the patient's arterial pulsations. ⋯ Spinal cord motion, as described, has important implications for neurosurgery, since it contradicts the previously held belief that oscillations of the spinal cord or dura mater imply a "free" or noncompressed spinal cord. Furthermore, spinal cord motion may play a role in the degradation of computerized tomography images of the cord, since these movements are maximized at the areas with the most severe pathology.
-
Journal of neurosurgery · Apr 1984
ReviewSome inquiries in neuroanesthesia and neurological supportive care.
Complications of performing neurosurgery in the sitting position have been well defined, and include cardiac and respiratory effects, air embolism, and pneumocephalus. Prophylactic measures and early diagnosis allow prompt therapy with minimal residual sequelae. ⋯ Patients with cerebrovascular disorders frequently have multisystem disease, and careful preanesthetic assessment and preparation ensure a more stable intraoperative and postoperative course. Many chemical and mechanical reactions follow an ischemic hypoxic insult, but appropriate therapeutic intervention and early establishment of cardiorespiratory support measures have shown promise in improving the neurological outcome in these patients.
-
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.
-
The microsurgical anatomy of the tentorial incisura was evaluated in 25 adult cadavers using X 3 to X 40 magnification. The area surrounding the incisura is divided into the anterior, middle, and posterior incisural spaces. ⋯ The arterial relationships in the anterior incisural space and the venous relationships in the posterior incisural space are extremely complex, since the anterior incisural space contains all the components of the circle of Willis and the bifurcation of the internal carotid and basilar arteries, and the posterior incisural space contains the convergence of the internal cerebral and basal veins and many of their tributaries on the vein of Galen. The discussion reviews tentorial herniation and operative approaches to the incisura.