Jacob Fidelis Ackermann (1765-1815): Pioneer in the Anatomical Description of Basilar Invagination.

Jacob Fidelis Ackermann was a German Medical Doctor born in 1765 in the city of Rüdesheim. Between 1789 and 1815 years he was professor of medicine at the universities of Mainz and Heidelberg, teaching the disciplines of anatomy, physiology, botany, and natural history. In his famous work on basilar invagination, Ackermann described and illustrated the cranial base flattening in two skulls from Italy. For this, he traveled through various European Alps analyzing autopsies and cranial specimens to describe the basilar invagination as an extremely inclined foramen magnum, with hypoplasia of occipital condyles, and elevation of the petrous part of the temporal bone. In his analyses, the thyroid gland dysfunction was the main etiology of the basilar invagination, in which the brainstem compression was a major pathological relevance discussed.