Journal Article

Third Nerve Palsy Secondary to Compression by Dolichoectatic Posterior Communicating Artery

Mandell, Daniel M., Margolin, Edward, Iizuka, Megumi, Donaldson, Laura

2022

Overview

The third cranial nerve exits the ventral surface of the midbrain between the posterior cerebral artery (PCA) and superior cerebellar arteries and runs just underneath the PCommA in the subarachnoid space. An exact cutoff for vessel diameter to be considered as dolichoectatic has been proposed for the basilar artery but has not been defined for the ICA and its branches.3 The prevalence varies from 0.05% to 6% with over 80% of intracranial dolichoectasia involving the vertebrobasilar system.3 Pathophysiology of dolichoectasia is unknown, but is considered to be the result of vessel wall’s response to various vascular risk factors and congenital vessel variations with changes in the tunica media due to matrix metalloproteinase activation and resultant injury of the muscle cells and elastic fibers. Dolichoectasia has been associated with older age, hypertension, coronary artery disease, and abdominal aortic aneurysms.3,4 Dolichoectasia of the ICA and its branches is much less common and less well characterized than that affecting vertebrobasilar circulation.

• Publisher: Cambridge University Press
• Subject: Aneurysms / Blood vessels / Cardiovascular disease / Letters to the Editor: Published Article / Medical imaging / Neurological disorders / Ophthalmology