Active head-impulse tests may help detect acute unilateral vestibulopathy: a preliminary study.

INTRODUCTION

Apart from conventional head-impulse tests (i.e., passive HITs), patency of the vestibulo-ocular reflex (VOR) can also be evaluated through self-generated HITs (i.e., active HITs). We aimed to evaluate the usefulness of active (self-generated) HITs in patients with acute unilateral vestibulopathy/vestibular neuritis (AUVP/VN) during the acute stages.

METHODS

We prospectively recruited 24 patients with AUVP/VN and 30 healthy participants from January 2019 to June 2026. All subjects underwent passive as well as active HITs. We compared the latency and amplitude of corrective saccades during active and passive HITs.

RESULTS

During active HITs, patients with AUVP/VN exhibited shorter latency (p < 0.001) and larger amplitude (p < 0.001) of their 1st corrective saccade compared with healthy participants. The latency of 1st corrective saccades during active HITs showed a positive correlation (p < 0.001), whereas the amplitude showed a negative correlation (p < 0.001) with the VOR gain during passive HITs. To differentiate patients with AUVP/VN from healthy participants, the sensitivity and specificity were 83.3 and 86.4%, respectively, at a cut-off latency of 242 ms for the 1st corrective saccade during active HITs with an area-under-the-curve (AUC) of 0.907. The sensitivity was 91.7% and the specificity was 93.3% at a cut-off value of 8.15° for amplitude of 1st corrective saccades, with an AUC of 0.971.

DISCUSSION: Detection of short-latency (≤ 242 ms) and large (≥ 8.15°) corrective saccades may help identify AUVP/VN during active HITs. Active HITs may provide complementary information for detecting acute unilateral vestibular hypofunction, although further validation is warranted.