A scanning electron microscopy study of post mortem autolytic changes in the human and rat cochleas

The use of SEM as an adjunct to TEM and electrophysiological examination of the cochlea is now well established. It has provided a relatively simple method of assessing the effect of noise, ototoxic drugs, electrical stimulation, etc. on the surface features of the organ of corti. A controlled experiment was undertaken to document the surface autolytic changes in rat cochleas by fixation at intervals up to eight hours post mortem. These were compared with human material fixed between 40 minutes and eight hours post mortem. The results complement previous light and transmission electron microscopy studies, gives insight into the optimal and acceptable fixation times for the two species and act as a guide for the interpretation of human material.