Idiopathic Sudden Sensorineural Hearing Loss Caused by Infarction of the Vestibulo-Cochlear Artery Can Be Detected by Testing Semicircular Canal Function and Audiometry: Proposal for Angiopathic Sudden Sensorineural Hearing Loss.

Background: Although the specific pathogenesis of idiopathic sudden sensorineural hearing loss (ISSNHL) remains unknown, vascular impairment is one of the leading causes of ISSNHL. Establishing diagnostic criteria for ISSNHL due to vascular impairment is essential. We hypothesized that isolated posterior semicircular canal dysfunction (IPSCD) in ISSNHL patients results from infarction of the vestibulo-cochlear artery (VCA). The aim of this preliminary retrospective study is to identify possible diagnostic characteristics of ISSNHL patients with IPSCD.

Methods: Seventeen ISSNHL patients were enrolled. They underwent video head impulse testing within 28 days of ISSNHL onset between September 2019 and November 2023. We obtained patient characteristics and clinical information, including results of audiometric and balance function tests. Eligible patients were divided into two groups according to the presence or absence of IPSCD. Patient characteristics and clinical information of the two groups were compared.

Results: Of the 17 ISSNHL patients included, 6 had IPSCD. Compared to the 11 patients without IPSCD, the 6 patients with IPSCD had significantly more coronary artery disease (odds ratio, infinite; p = 0.03) and had regularly used antithrombotic medications (odds ratio, infinite; p < 0.01). The audiogram shapes of the six ISSNHL-IPSCD patients were profound, flat, or high-frequency descending forms.

Conclusions: Given that VCA impairment is associated with profound, flat, and high-frequency hearing loss and consistent with the arterial anatomy of the inner ear, ISSNHL-IPSCD patients are more likely to have vascular impairment. Conducting trials that target ISSNHL-IPSCD patients may lead to the discovery of new and effective treatments for ISSNHL.