Assessing the Role of Nystagmus Slow Phase Velocity as a Prognostic Indicator in Idiopathic Sudden Sensorineural Hearing Loss: A Prospective Study.

INTRODUCTION

Idiopathic sudden sensorineural hearing loss (ISSNHL) exhibits a diverse range of clinical presentations and treatment responses. Currently, there are no established variables that clinicians can utilize for the purposes of patient counseling when treating ISSNHL.

MATERIALS AND

METHODS

This prospective study involved 35 patients diagnosed with ISSNHL who were treated with oral and intratympanic steroid injections. We measured the peak and average slow phase velocity (SPV) (°/sec) of nystagmus after caloric stimulation during the first session of intratympanic steroid injection (ITI), and four variables were evaluated: age, time elapsed before treatment (ET), gain, and pure tone average (PTA) posttreatment. An association between these variables was determined using Spearman's Rho statistical analysis, followed by regression modeling.

RESULTS

We found a strong significant correlation between SPV and gain and PTA posttreatment (Spearman Rho 0.000). A significant correlation between SPV and ET was also detected (Spearman Rho 0.05). The linear regression analysis indicated that for every 1° increase in SPV, there is an expected increase of 0.27 dB in gain and a decrease of 0.18 dB in PTA posttreatment. Furthermore, an SPV of 17.7 (°/sec) demonstrated a strong correlation with Siegel grade 1 posttreatment ( p 0.000).

CONCLUSIONS

The SPV (°/sec) of nystagmus during the first ITI may serve as a valuable tool for patient counseling in the management of ISSNHL, thereby encouraging the continuation or consideration of alternative treatment options. Further studies are warranted to validate these findings.