The Association of Vascular Loops of Anterior Inferior Cerebellar Artery and Vestibulocochlear Symptoms

Abstract

Aim: The association of vascular loops of anterior inferior cerebellar artery (AICA) with vestibulocochlear symptoms including hear loss, tinnitus, and vertigo is controversial. We aimed to investigate the relationship between vestibulocochlear symptoms and AICA vascular loop syndrome on magnetic resonance imaging (MRI). Materials and Methods: The patients underwent a posterior fossa MRI examination were reviewed regarding the presence of hear loss, tinnitus, and vertigo by an experienced ear-nose-throat specialists' physical examinations. The incidences of these lesions in the patients with and without AICA vascular loop syndromes were compared. Furthermore, the correlation between the AICA vascular loop syndrome subtypes (grade 1-3) and the incidence of the symptoms were analyzed. Results: A total of 502 patients (1004 ears) were included in this study. Vascular loops were demonstrated in 150 ears (14.9%). Subtype 1 was observed in 97 (9.7%), subtype 2 in 40 (4.0%) and subtype 3 in 13 (1.3%) ears. The incidences of tinnitus, hear loss, and tinnitus + hear loss were statistically significantly higher in the patients with vascular loops than without vascular loops (p: 0.000042, p: 0.0446906, p: 0.028106, respectively). However, there was not a significant correlation between the incidence of the symptoms and the grade of the vascular loop formation (p>0.05). Vertigo incidence was very similar among the patients with no, with one-sided and with both-sided AICA vascular loops (41.5%, 39.8% and 46.2%, respectively) with no statistical difference (p>0.05). Conclusion: The AICA vascular loop is associated with either tinnitus or hear loss but there is no correlation with the degree of the vascular loops. There is no relationship between AICA vascular loops and vertigo.