The clinical spectrum of amiodarone-associated optic neuropathy

• Published in: Journal of the National Medical Association Vol. 96; no. 11; pp. 1477 - 1491
• Main Authors: JOHNSON, Lenworth N, KROHEL, Gregory B, THOMAS, Eric R
• Format: Journal Article
• Language: English
• Published: Thorofare, NJ Slack 01.11.2004; Elsevier Limited; National Medical Association
• Subjects: Aged; Amiodarone - adverse effects; Anti-Arrhythmia Agents - adverse effects; Biological and medical sciences; Diseases of visual field, optic nerve, optic chiasma and optic tracts; Dose-Response Relationship, Drug; Female; General aspects; Humans; Male; Medical sciences; Middle Aged; Ophthalmology; Optic Disk - drug effects; Optic Nerve Diseases - chemically induced; Optic Nerve Diseases - classification; Optic Nerve Diseases - pathology; Time Factors; Antianginal agent; Nervous system diseases; Optic neuropathy; Coronary vasodilator agent; Loss; Amiodarone; visual field loss; Antiarrhythmic agent; Iodine Organic compounds; Retrobulbar; Spectrum; Eye disease; Cranial nerve disease; Visual field disease; Vision; Visual field defect; Tropical medicine; vision loss
• ISSN: 0027-9684; 1943-4693

To describe the clinical spectrum of amiodarone-associated optic neuropathy. Observational cases series and review. Of 55 cases, the median interval for onset of optic neuropathy was four months after initiating amiodarone; 88% occurred within 12 months. Seven (13%) patients were asymptomatic. Twenty-two (40%) patients presented with sudden visual loss, while 26 (47%) had insidious loss of vision. Visual acuity ranged from 20/15 to light perception; 10 (18%) patients had legal blindness with visual acuity of 20/200 or worse. Visual field loss was present in 91% of cases. Color vision loss was present in eight (40%) of 20 cases. Optic disc edema was present in 85% of cases, while eight (15%) patients had retrobulbar optic neuropathy, without evidence of disc edema. Optic disc edema resolved over a median time of three months. Five patients had raised intracranial pressure on lumbar puncture. We were able to classify amiodarone-associated optic neuropathy into five clinical categories with respect to temporal characteristics and optic nerve appearance: insidious-onset (43%), acute-onset (28%), retrobulbar (13%), increased intracranial pressure (8%), and delayed-progressive onset (8%). Most cases of optic neuropathy commenced within 12 months of initiating amiodarone, with the median onset being four months. Over 10% of patients will have no visual symptoms at the onset. Ophthalmologic examinations within the first 12 months--and particularly within four months of initiating amiodarone--should improve early detection of amiodarone-associated optic neuropathy.