[Ultrastructural morphometric analysis of the spiral ganglion in guinea pigs (author's transl)].

This is the first morphometric analysis of the cochlear spiral ganglion. Therefore the ganglion was subdivided in precisely defined compartments. We found that the normal, untreated spiral ganglion in guinea pigs contains 58% ganglion cells of the granular type, 26% satellite cells and Schwann cells, 8.6% extracellular space, 6.4% myelinated nerve fibers and 1% ganglion cells of the filamentous type. The granular ganglion cell consists in 83% out of cytoplasm and in 17% out of nuclei. The cytoplasm is containing 13% ribosomes, 12% mitochondria, 10% RER, 2.1% Golgi apparatus, 1.3% lysosomes. Based on these quantitative datas we expect to detect alterations of the normal structure earlier and more precisely under pathophysiological conditions as before.