Correct! You are looking at normal ocular pursuit movements, but the patient has an abnormal head impulse test and an abnormal dynamic visual acuity test. In the head impulse test, the examiner grasps the patient’s head and moves it briskly from side to side, watching for conjugate recovery saccades in a direction opposite to the head movement, which would indicate an impaired vestibulo-ocular reflex (VOR). You probably noticed those recovery saccades in this patient video. In the dynamic visual acuity test, which is not part of the standard ophthalmologic examination (visual acuity is always tested with the head still), the same head maneuver is performed as the patients reads the Snellen chart. If a defective VOR carries the eyes off target, visual acuity will be degraded. That happened here (the patient reported that shaking his head made his vision unclear). These abnormalities are usually due to dysfunction of the inner ear structures, the most common cause being aminoglycoside toxicity. In fact, this patient had been treated with tobramycin for a serious wound infection. Those who suffer from this ototoxicity often also complain of imbalance, especially when they walk on poorly-lighted and uneven surfaces. The deficits are permanent, but symptoms lessen over time, perhaps because patients avoid the inciting circumstances.

Incorrect

Incorrect

Incorrect