Quantitative, histological and ultrastructural studies of peripheral nerve in arteriosclerotic non-diabetic patients.

The superficial peroneal nerve was taken from 12 arteriosclerotic non-diabetic patients just after amputation of a leg. Preparations of teased fibers were performed in 8 cases. Specimens were studied by light and electron microscopy in all cases. Histograms of myelinated fibers in transverse semi-thin sections showed that depletion of myelinated fibers varied from case to case, with no selective vulnerability in either the large or the small diameter group. There was a dramatic loss of myelinated fibers in only one case. No real nerve infarct was observed. In most cases, regions of Wallerian-like degeneration were prevalent; however, myelino-axonal changes were severe only in a few cases. Axons with organelle aggregates were seen in some cases. Figures of segmental demyelination were not numerous in this series. Unmyelinated fibers were also damaged, and the degree of involvement differed from case to case. Pathological changes observed in this study confirm the relative resistance of peripheral nerve to ischemia.