Gasperini's syndrome: its neuroanatomical basis now and then.

Crossed brainstem syndromes consist of ipsilateral impairment of cranial nerves III-XII and contralateral impairment of the pyramidal and sensory tracts. Gasperini's syndrome, described in 1912 by the Italian internist Ubaldo Gasperini, is one of them. It results from a lesion of the caudal pontine tegmentum and is most frequently defined as ipsilateral impairment of cranial nerves V, VI, VII, and VIII and contralateral sensory loss. Since no autopsy was performed to confirm Gasperini's clinical observations, we analyzed all elements of his syndrome from a current perspective as well as in the light of the anatomical knowledge available to him. This resulted in a historical survey of the development of neuroanatomy over the last 300 years.