MEDICAL TREATMENTS FOR ABNORMAL EYE-MOVEMENTS - PHARMACOLOGICAL, OPTICAL AND IMMUNOLOGICAL STRATEGIES

Purpose: To review current medical treatments for nystagmus and saccad ic intrusions, and their visual consequences. Methods: Evaluation of s tudies that have used reliable measurement of eye movements and visual acuity before and after treatment. Interpretation of results in light oi physiological and pharmacological studies in animals, and recent i mmunological advances. Results: There are many case reports of patient s with abnormal eye movements being improved by a variety of drugs, bu t few double-blind, controlled studies have been carried out. Most pro mising are agents that mediate their effects through the neurotransmit ter gamma-aminobutyric acid: such drugs include baclofen and gabapenti n. Botulinum toxin, injected into selected extraocular muscles or the retrobulbar space, can abolish nystagmus for several months, but often produces troublesome side-effects, such as diplopia and ptosis, which limit its value. Optical measures to either reduce nystagmus by manip ulating vergence angle, or reduce retinal image motion, help some pati ents. Opsoclonus occurring in association with cancer may be successfu lly treated with an immune-adsorption technique using a protein A colu mn. Conclusions: There is need for controlled, blinded studies to eval uate the many agents reported to improve visual symptoms in individual patients with abnormal eye movements.