|
Medical Definition of Pedunculus cerebellaris inferior
1. Large paired bundles of nerve fibres which develop on the dorsolateral surfaces of the upper medulla, extend under the lateral recesses of the rhomboid fossa and curve dorsally into the cerebellum medial to the middle cerebellar peduncle; composed of a larger (lateral) bundle, the restiform body, and a small (medial) bundle, the juxtarestiform body. Fibres forming this composite bundle originate from spinal neurons and medullary relay nuclei. The largest constituent (restiform body) is crossed fibres from the inferior olive; it also contains the dorsal spinocerebellar tract and cerebellar projections from the lateral reticular nucleus, the accessory cuneate nucleus, the paramedian reticular nuclei and the perihypoglossal nuclei. Vestibulocerebellar fibres are placed medially in the inferior cerebellar peduncle and are usually separately identified as the juxtarestiform body. Synonym: pedunculus cerebellaris inferior. (05 Mar 2000)