Optical coherence tomography angiography findings in patients with sudden sensorineural hearing loss

Sudden sensorineural hearing loss (SSNHL) is a common otological condition; however, its pathophysiology and prognostic factors remain unclear. We aimed to investigate the relationship between retinal microvascular changes and the severity and prognosis of SSNHL using optical coherence tomography angiography (OCTA), exploring the role of ocular microcirculation. A prospective cohort study was conducted on 88 patients with SSNHL between December 2019 and December 2022. All patients underwent OCTA on the affected side to assess retinal vasculature. Parameters analyzed included vessel density (VD), vessel length density (VLD), choriocapillaris flow deficit (CCFD), along with retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness. Hearing recovery was classified using the Modified American Academy of Otolaryngology-Head and Neck Surgery criteria, and correlations with OCTA findings were assessed. Patients with poor hearing recovery (Group 1) showed significantly thinner RNFL and GCL compared to those with improved hearing (Group 2). The superficial (SCP) and deep (DCP) capillary plexus VD had a significant negative correlation with initial hearing loss severity (rho = -0.272 and - 0.306, respectively; p < 0.05), suggesting that reduced ocular blood flow may be related to SSNHL severity. No significant correlations were observed for VLD and CCFD. Reduced RNFL and GCL thickness may serve as prognostic markers for SSNHL. The inverse correlation between SCP/DCP VD and hearing loss severity suggests that arterial hypoperfusion may contribute to SSNHL. Our results support the potential utility of OCTA as a noninvasive method for evaluating ocular blood flow in SSNHL patients.