Voluntary nystagmus associated with accommodation spasms.

BACKGROUND Voluntary nystagmus has been recognized as a pendular, rapid, conjugate, primarily horizontal, benign eye movement initiated and maintained by voluntary effort. CASE A 10-year-old Japanese girl presented with voluntary nystagmus associated with accommodation spasms. Her chief complaints, intermittent blurred vision, headache, and soreness of the eyes, were thought to be related to the voluntary nystagmus and accommodation spasms. FINDINGS The waveform of the nystagmus appeared pendular, the frequency was 13-15 Hz, and the amplitude was 3-5 degrees. Scanning laser ophthalmoscopic video images clearly demonstrated vertical and torsional components in addition to the horizontal eye movements. Her refraction was unstable, varying between -0.5 diopters (D) and -5.5 D, and the recording of the accommodometer increased to -12.0 D when nystagmus was initiated. CONCLUSIONS This may be a unique form of voluntary nystagmus that consists of horizontal, vertical, and rotational components associated with accommodation spasms. Observation of this patient continues, without any further treatment or examination.