Faculty Bibliography

For neuroradiologic evaluation of parasellar lesions, a wide array of examinations may be utilized. CT and MRI are used in the assessment of these lesions to establish the diagnosis and to assist the neurosurgeon in defining the precise location. Careful neuroradiologic assessment and close cooperation between the neurosurgeon and the neuroradiologist have much bearing on the surgical planning and eventual outcome of the patient

The term craniovertebral junction refers to an area comprising the inferior portion of the occipital bone surrounding the foramen magnum and the first two cervical vertebrae. A variety of anomalies of bony, meningeal, and neural elements are known to occur in this region, producing a wide spectrum of clinical symptoms. These can range from dizziness, ataxia, and nuchal headaches to obvious quadriparesis and cranial nerve palsies. Often the symptoms are vague with an evolution marked by temporary exacerbations and remissions. The diagnosis can be difficult, and in our experience is best achieved by combining a neurotologic and neurologic evaluation. We discuss here the symptoms and diagnosis in ten patients with lesions at the craniovertebral junction. The surgical management of two cases of basilar invagination is described, and the controversies regarding the technique are discussed

The objective of this study was to evaluate the effects of mannitol, given over different time periods, on regional cerebral blood flow (rCBF) in patients with intracranial aneurysms. Seven patients with unruptured aneurysms (Group I) and 16 patients with Grade I and II subarachnoid hemorrhage (SAH) (Group II) received 1.5 gm/kg/8 hrs of 20% mannitol intravenously over a 24-hour period. Seven other patients with unruptured aneurysms (Group III) received 1.5 gm/kg of mannitol over 8 hours only. The last seven patients with unruptured aneurysms (Group IV) received the same dose, but as an intravenous bolus. Over a period of 24 hours, the patients underwent serial measurements of rCBF, intracranial pressure (ICP), mean blood pressure (MBP), cardiac output, and cerebral metabolic rate of oxygen consumption (CMRO2). Mannitol, when given as a continuous intravenous infusion, increased rCBF significantly without increasing MBP or decreasing ICP. This increase was more pronounced in SAH patients. The effects of mannitol lasted for 18 hours when given over an 8-hour period only; however, when it was given as a bolus, the increase in rCBF lasted for 24 hours, cardiac output tended to increase, and the effect on CMRO2 was variable