Microvacuolar neuronopathy: a postmortem artifact of sensory neurons.

Vacuolar changes in primary sensory neurons have been described in the context of disease and injury. In this work we examine microvacuolation of rat dorsal root ganglion (primary sensory) neurons. This change, attributed to swelling of mitochondria, had a direct relationship with the duration of the post mortem interval prior to harvesting. Similar microvacuolation, but also the presence of subplasmalemmal scalloping was prominent in dorsal root ganglion samples from patients without known peripheral disease undergoing post mortem examination. Both types of vacuolar change differ from "signet ring" vacuolation linked to neuron injury or disease. We suggest that care is required in evaluating vacuolar changes in primary sensory neurons. Microvacuolation is probably not a feature of sensory neuron disease.