Aneurysm of the Internal Carotid Artery Pressing on Dorello’s Canal in a Patient with Bilateral Abducens Nerve Palsy: Case Report

Abstract

Objective: Abducens nerve palsy (ANP) has an incidence of 11.3/100,000. ANP related to pressure of the aneurysm on the Dorello’s canal is unusual. We report a case of bilateral ANP following head trauma.

Case: A 31-year-old woman was admitted for the evalu­ation of diplopia began after trauma.  In the diagnostic imaging; the magnetic resonance imaging (MRI) revealed the normal course of bilateral abducens nerve (AN) in the pontine cistern. The adjacent anatomy of the right AN from pons up to the oculer bulb was normal.  But the distal part of the left ICA petrous segment at the level of foramen lacerum had a remarkable loss of signal void. Multidetector computed tomography  angiogram demonstrated a left distal petrous ICA aneurysm which was under the Dorello’s canal and remodeling the clivus.

Conclusion: We estimated the left ANP was caused by the pressure of the aneurysm. And the right ANP was probably due to the trauma  the patient had experienced.

Keywords

• Abducens Palsy,Aneurysm,Dorello’s Canal; MRI; Trauma

Aneurysm of the Internal Carotid Artery Pressing on Dorello’s Canal in a Patient with Bilateral Abducens Nerve Palsy: Case Report

Öz

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