Objective:

The present study aimed to assess the accuracy and clinical utility of the HINTS examination in patients with idiopathic sudden sensorineural hearing loss (SSNHL) and vertigo.

Background:

SSNHL with vertigo poses a diagnostic challenge because it can mimic central lesions such as anterior inferior cerebellar artery infarction. Although the head impulse, nystagmus, and test of skew (HINTS) examination is widely used to differentiate peripheral from central causes in acute vestibular syndrome, its reliability in idiopathic SSNHL with vertigo remains uncertain. 

Design/Methods:

We reviewed medical records of 121 patients with idiopathic SSNHL and vertigo who presented to two tertiary university hospitals in South Korea. All patients underwent eye-movement recording, video head impulse tests, and caloric tests, along with brain MRI to exclude central lesions. The HINTS exam was interpreted as “benign” or “dangerous” based on standard criteria. False positive and true negative rates of the HINTS exam were calculated in patients with spontaneous nystagmus (SN).

Results:

SN was observed in 49% and benign paroxysmal positional vertigo in 34%. Abnormal caloric responses were identified in 48%, while abnormal horizontal head impulse tests (HITs) occurred in 29%. Concordance between caloric and horizontal HITs was noted in 80% of patients, whereas 17% showed abnormal caloric responses despite a normal horizontal HITs, indicating selective low-frequency vestibular dysfunction. Among 59 patients with SN, 61% exhibited “dangerous” HINTS patterns in the absence of central lesions on MRI, indicating a high false-positive rate. Misclassification was particularly frequent in those with ipsilesional SN (89%), compared with those with contralesional SN (31%, p<0.001). Skew deviation and direction-changing nystagmus were rare. 

Conclusions:

This study showed that the HINTS examination frequently produced “dangerous” patterns in idiopathic SSNHL and vertigo, suggesting the limited specificity of the HINTS examination in this setting. Clinicians should therefore interpret these findings with caution and complement bedside examination with formal audiovestibular testing.