Abstract
The nests of neuroglial tissues have been observed beyond the Schwann-glial junction of the eighth nerve specimens from patients with known vestibular disorders. The inner ears of a 71-year-old male who died of lung carcinoma were fixed with 2% paraformaldehyde and 2% glutaraldehyde one and one-half hours after death. He was reported to have no auditory or vestibular complaints. The tissue was postfixed in 2% osmium tetroxide. The superior vestibular nerve was removed intact and studied with an electron microscope. The neuroglial tissues were observed among the myelinated vestibular nerve fibers in the distal part close to the cribriform area. They consisted of bundles of numerous cytoplasmic processes of fibrous astrocytes. The process contained bundles of abundant filaments, endoplasmic reticulum and mitochondria. These glial processes were joined by a double membrane and numerous tight junctions were observed. The filaments extended as parallel arrays in the processes. It has been suggested that neuroglial tissues are focus of the eighth nerve tumor or causes of various vestibular disorders including Meniere's disease. However, this study exhibits that neuroglia in the vestibular nerve could be normal histological characteristics.
