title: Magnetic resonance imaging based classification of anatomic relationship between the cochleovestibular nerve and anterior inferior cerebellar artery in patients with non-specific neuro-otologic symptoms.
abstract: In this study, we aimed to assess anatomical relationship between the anterior inferior cerebellar artery (AICA) and cochleovestibular nerve (CNV) in patients with non-specific cochleovestibular symptoms using magnetic resonance imaging (MRI). One-hundred and forty patients with non-specific neuro-otologic symptoms were assessed using cranial and temporal MRI. Classification was performed according to four different types of anatomical relationship observed between the AICA and CVN. In type 1 (point compression), the AICA compresses only a limited portion of the CVN. In type 2 (longitudinal compression), the AICA approaches the CVN as both traverse parallel to each other. In type 3 (loop compression), the vascular loop of the AICA encircles the CVN. In type 4 (indentation), the AICA compresses the CVN so as to make an indentation in the nerve. The anatomical relationship between the CVN and AICA was encountered in 19 out of 140 (13.6%) patients (20 ears). The VCC was unilateral in 18 patients (94.7%) and bilateral in one patient (5.3%). There was no other vascular structure causing VCC to the CVN except for vertebral artery that was seen in 2 out of 140 patients (1.4%). These were unilateral cases. There were tinnitus, vertigo or dizziness, hearing loss, and both hearing loss and vertigo in 5 (25%), 13 (65%), 1 (5%) and 1 (5%) ears of 20 patients, respectively. There was no relationship between the cochleovestibular symptoms and type of compression (p>0.05). Neurovascular relationship between the CVN and AICA can be imaged properly using MR and MR based classification may help reporting this relationship in a standard way. Although, MR images can show the anatomical relationship accurately, diagnosis of vascular conflict should not be based on imaging findings alone.
authors.affiliation: Department of Radiology, Faculty of Medicine, University of Gaziantep, Gaziantep, Turkey.
authors.forename: Akif
authors.initials: A
authors.lastname: Sirikci
authors.forename: Yildirim
authors.initials: Y
authors.lastname: Bayazit
authors.forename: Enver
authors.initials: E
authors.lastname: Ozer
authors.forename: Ayhan
authors.initials: A
authors.lastname: Ozkur
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Adaletli
authors.forename: M Ali
authors.initials: MA
authors.lastname: Cüce
authors.forename: Metin
authors.initials: M
authors.lastname: Bayram
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001158:Arteries / Q000473:pathology; D002530:Cerebellopontine Angle / Q000098:blood supply / Q000473:pathology; D002531:Cerebellum / Q000098:blood supply*; D002560:Cerebrovascular Circulation / Q000502:physiology; D004244:Dizziness / Q000175:diagnosis; D005260:Female; D034381:Hearing Loss / Q000175:diagnosis; D006801:Humans; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000145:classification*; D014012:Tinnitus / Q000175:diagnosis; D014717:Vertigo / Q000175:diagnosis; D000159:Vestibulocochlear Nerve / Q000473:pathology*; D000160:Vestibulocochlear Nerve Diseases / Q000145:classification*