Abstract
A 31-year-old female with oculocutaneous albinism presented with congenital nystagmus and positional nystagmus of the benign paroxysmal type. The patient had had abnormal ocular movements since 4 years of age. She developed severe vertigo when she moved her head 7 days before she visited our hospital. Stenger's head positioning test elicited pure rotatory nystagmus accompanied by vertigo. A horizontal pendular eye movement of about 1° width and 4Hz frequency was observed continuously at any eye or head position; its width was smallest when she gazed up about 10° to the right electronystagmography (ENG) disclosed that this pendular eye movement was weaker with the eyes open in darkness and was absent with the eyes closed. ENG also disclosed saccadic pursuit, poor optokinetic nystagmus and very weak caloric nystagmus. The characteristics of the horizontal eye movements were compatible with congenital nystagmus. Neurological findings, other than eye movements, blood and urine analyses, auditory brainstem response, visually evoked potential and NMR-CT study of the brain were normal.
Congenital nystagmus is a very common symptom in patients with albinism and it usually is not accompanied by vertigo. The pure rotatory nystagmus observed on head positioning in this patient was thought to be “positional nystagmus of benign paroxysmal type” or positional nystagmus of peripheral vestibular origin. A pure tone audiogram showed about 20 to 30dB bilateral sensori-neural hearing loss at 4 and 8kHz. These findings could be due to fragility of the inner ear of albino patients.
