Sudden Sensorineural Hearing Loss Associated with the Presence of a Vascular Loop in the Internal Auditory Canal. Case Report

The vascular loop refers to a trajectory abnormality of the antero-inferior cerebellar artery or its branch in the internal auditory canal. The Chavda radiological classification identifies three types of trajectory depending on the depth of penetration of the loop at the level of the internal auditory canal. The article presents the case of a 26-year-old patient admitted to the ENT department for left ear sudden sensorineural hearing loss and dizziness. The 3D Fiesta-C axial sequence MRI shows the presence of the vascular loop inside the internal auditory canal, without exceeding half of it. The hearing loss had an unfavourable evolution, without recovery after treatment with steroids and vasodilators. Sudden sensorineural hearing loss may be a consequence of the presence of the vascular loop in the internal auditory canal. The prognosis for recovery from hearing loss is poor if the loop is at least type II.