CT pneumomeatography in the diagnosis of small acoustic neuromas.

The introduction of a small quantity of air by lumbar puncture in the lateral decubitus position followed by high-resolution computerized tomography (CT) scanning is a simple method allowing optimal visualization of the cerebellopontine angle cistern and the internal auditory meatus. Our experience with 37 CT pneumomeatographies in 22 patients who had clinical and audiometric findings suggestive of retrocochlear lesions is presented. Thirty-two examinations were normal, and 5 revealed small acoustic neuromas. In all cases, conventional X-rays, multidirectional tomography and contrast CT were nonconclusive. We advocate that CT pneumomeatography be the procedure of choice in the diagnosis of purely intracanalicular or very small extracanalicular acoustic neuromas.

Expression of epidermal growth factor receptors in human brain tumors.

The expression of receptors for epidermal growth factor (EGF-R) was determined in 29 samples of brain tumors from 22 patients. Primary gliogenous tumors, of various degrees of cancer, five meningiomas, and two neuroblastomas were examined. Tissue samples were frozen in liquid nitrogen immediately after the operation and stored at -70 degrees until use. Cerebral tissue samples from 11 patients who died from diseases not related to the central nervous system served as controls. Immunoprecipitation of functional EGF-R-kinase complexes revealed high levels of EGF-R in all of the brain tumors of nonneuronal origin that were examined. The level of EGF-R varied between tumors from different patients and also between specimens prelevated from different areas of the same tumor. In contrast, the levels of EGF-R from control specimens were invariably low. The biochemical properties of EGF-R in brain tumor specimens were found to be indistinguishable from those of the well-characterized EGF-R from the A-431 cell line, derived from human epidermoid carcinomas. Human brain EGF-R displays a molecular weight of 170,000 by polyacrylamide-sodium dodecyl sulfate gel electrophoresis. It is phosphorylated mainly in tyrosine residues and shows a 2-dimensional phosphopeptide map similar to that obtained with the phosphorylated EGF-R from membranes of A-431 cells. Our observations suggest that induction of EGF-R expression may accompany the malignant transformation of human brain cells of nonneuronal origin.

Carbon dioxide laser surgery of basal meningiomas.

This preliminary report summarizes our results with laser surgery in patients with basal meningiomas (8 basilar and 1 intraventricular extending also into the third ventricle). Illustrative preoperative and postoperative CT scans are included. The advantages and limitations of this surgical technique are discussed briefly.

Dumb-bell neurinoma of the hypoglossal nerve.

A unique case of dumb-bell neurinoma of the hypoglossal nerve is presented. The importance of hemiatrophy of the tongue is stressed for early diagnosis of the lesion. The myelocisternogram is the single most important contrast study confirming the intracranial extension of the tumour. Total dissection of the tumour capsule may not be feasible in all cases.

Anterior interbody fuson for cervical osteomyelitis. Reversal of quadriplegia after evacuation of epidural spinal abscess.

Interbody fusion for stabilization of the cervical spine after osteomyelitic destruction of the body of C5 vertebra is reported in a patient with quadriplegia and sphincter disturbances secondary to an epidural abscess. The successful union of the bone graft along with complete neurological recovery after anterior decompression and evacuation of the epidural mass seem to justify the procedure.