1994 Volume 1994 Issue Supplement69 Pages 7-13
We used three cats with iris versicolor (Waardenburg syndrome) for study of the ear. Under general anesthesia, after the auditory brainstem response (ABR) was performed, the head was perfused in vivo with 2% glutaraldehyde. After removal of the temporal bone and perfusion with 2% osmic acid from the round window to the oval window, specimens of membranous labyrinths to be observed by scanning electron microscopes (SEM) were processed by the surface preparation technique. The results were as follows: Two of the three cats demonstrated a clear wave, but one had no response on ABR. The former showed normal cochlear findings on SEM, but in the latter the hair cells of the organ of Corti had all disappeared, and total degeneration of the organ of Corti and remnants of supporting cells, especially pillar cells were observed on the basilar membrane. The cochlear duct had collapsed and Reissner's membrane was adherent to the upper surface of the tectorial membrane. The stria vascularis was found to have atrophied.
