Peripheral vestibular assessment

Peripheral vestibular assessment focuses on the vestibulo-ocular reflex (VOR), the eye movement that keeps vision stable during head motion. The main tests covered are dynamic visual acuity, gaze stability, the head impulse test, and the head shake test, all used to identify unilateral vestibular hypofunction. Dynamic visual acuity uses a Snellen chart to compare vision at rest and during head movement; a drop of three or more lines suggests reduced VOR function. Gaze stability is a simpler clinical version that checks whether a person can keep their eyes fixed on a target without blurring, dizziness, or compensatory body movement. The head impulse test examines rapid passive head turns to detect a corrective “double jump” of the eyes, which strongly indicates peripheral vestibular weakness on the side being tested. The explanation also covers nystagmus, including how to define its direction, how peripheral and central patterns differ, and why visual fixation can suppress it. Head shake testing is used to expose hidden imbalance by provoking nystagmus, making it highly sensitive but not specific. Overall, learners can expect a practical framework for interpreting these findings together.