[Lafora-like neuronal inclusions in the nucleus tegmentalis pedunculopontinus--their relation of aging (author's...

At routine postmortem examinations, peculiar basophilic inclusion bodies were often encountered in nerve cells of the nucleus tegmentalis pendunculopontinus in the lower midbrain. Morphology and histochemistry of these inclusions were most similar to Lafora bodies commonly seen in Lafora type myoclonus epilepsy. Incidence and distribution of such Lafora-like bodies were examined in transverse sections through the lower midbrain of 38 patients selected at random who did not have storage or degenerative diseases. In neurons of 14 out of these 38 cases, at least one Lafora-like body was found. Their distribution was restricted to the nucleus tegmentalis pedunculopontinus. Almost every body occupied the neuronal perikarya to various degrees or they were also seen in the neuropil. Clinical data and autopsy findings revealed age-dependence of these bodies and also probable correlation to cerebral infarction: 5 or the 14 positive cases had old cerebral infarcts. In addition to Lafora type myoclonus epilepsy and rare instance of certain degenerative diseases, also aging may induce formation of Lafora-like bodies, though regionally restricted, in neurons.