Vascular malformation of the brainstem: report of a case with long duration and fluctuating course.

We studied a patient with a vascular malformation within the pons and medulla, affecting the cranial nerve nuclei, ascending and descending pathways, and cerebellar peduncles and adjoining structures. The symptoms had been present for more than 50 years. They were fluctuating in the beginning but later were progressive. The malformation probably had its origin during the first month of embryonic life.