Occult intrasacral meningocele: clinical and radiographic diagnosis.

We evaluated four patients who had occult intrasacral meningocele with multimodality radiographic imaging techniques. The clinical features, radiological findings, gross appearances of the lesion at surgery, surgical technique, histopathological features of the cyst wall, and surgical outcome are described. The role of magnetic resonance imaging in the preoperative evaluation compared with standard radiographic techniques is discussed.

Nasal encephaloceles: definitive one-stage reconstruction.

Nasal encephaloceles can cause complex deformities of the naso-orbital skeleton. As the encephalocele pushes through a defect in the facial skeleton it causes lateral displacement of the medial orbital walls. Correction of this skeletal deformity is necessary to achieve a normal facial contour.

Chronic ventricular cerebrospinal fluid sampling, drug injections, and pressure monitoring using subcutaneous reservoirs in monkeys.

Animal models enabling reliable access to ventricular cerebrospinal fluid (CSF) are crucial to the study of neuropharmacological and neurotoxicological effects of cytotoxic agents used to treat central nervous system neoplasms. This investigation concludes that 4th ventricular catheterization using subcutaneous CSF reservoirs in rhesus monkeys: (a) provides chronic access to sterile CSF without chronic immobilization, (b) enables mixing of injected drugs with lateral ventricular CSF, (c) permits sensitive monitoring of intraventricular pressure and (d) does not produce tissue damage during cannula implantation or breakdown of the blood-brain barrier.

Cardiac arrhythmias resulting from experimental head injury.

The cardiovascular events resulting from experimental head injury were studied to determine the incidence of cardiac arrhythmias and to define the autonomic mechanisms responsible for these changes. Electrocardiograms and arterial blood pressure were recorded in anesthetized monkeys before and after the animals were subjected to temporoparietal head impact. Cardiac arrhythmias and hypotension occurred immediately following impact in every animal studied.