Jacobs Journal of Anatomy and Physiology

Petroclival Canal: A Rare Passage of the Abducens Nerve at the Petroclival Region-Anatomic Variation

Published on: 2018-12-20


Petroclival canal (PCC), which occurs as a result of petrosfenoidal ligament (PSL) calsification is a different passage for the abducens nerve path. During performing the anatomic dissection of petroclival region of a the cadaveric specimen, we incidentally noted existence of a bony canal in which abducens nerve was passing through petro-occipital fissure (POF), petroclival canal. This variation was also confirmed by thin sections of computed tomography images. PSL was found as a thin fibrous band between the petrous apex and posterior clinoid process at an interdural space, however the sixth cranial nerve were passing through bony canals in the petro-occipital fissures to the superior posterior side of the lacerum segment of the internal carotid artery on both sides. Passage of the abducens nerve through a bony canal is presumed to be clinically important in terms of fractures reaching up to the petroclival region and there is a risk of nerve injury during both anterior transpetrosal or endoscopic approaches through the petroclival region.


Abducens Nerve, Ossification, Petro-Clival Canal, Petro sphenoidal Ligament