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The Rodent Model of Nonarteritic Anterior Ischemic Optic Neuropathy rNAION
Published on: November 20, 2016
Short-term treatment with oral amiodarone resulting in bilateral optic neuropathy and permanent blindness
1University of Southern Denmark, Faculty of Health Sciences, Odense M, Denmark.
Insights
A patient developed toxic optic neuropathy, leading to blindness, after taking amiodarone for atrial fibrillation. This highlights a serious potential side effect of this common heart medication.
Area of Science:
- Ophthalmology
- Cardiology
- Pharmacology
Background:
- Atrial fibrillation management often involves antiarrhythmic drugs like amiodarone.
- Amiodarone is effective in maintaining sinus rhythm but carries potential toxicities.
Observation:
- A 66-year-old male patient experienced progressive bilateral vision loss.
- Symptoms included blurred vision and cloudy areas, starting three weeks after amiodarone initiation.
Findings:
- The patient was diagnosed with amiodarone-induced toxic optic neuropathy.
- Visual acuity decreased to 0.05 (1.3 LogMAR) in both eyes, resulting in legal blindness.
Implications:
- This case underscores the critical need for ophthalmological monitoring in patients on long-term amiodarone therapy.
- Early detection and discontinuation of amiodarone may be crucial for mitigating vision loss.
Abstract:
A 66-year-old man was hospitalised due to worsening of his atrial fibrillation, and successfully underwent an electrocardioversion to restore sinus rhythm. He was discharged with a prescription of 600 mg amiodarone daily to retain the sinus rhythm prospectively. 3 weeks after discharge, he noticed that his vision became blurry with cloudy areas spreading throughout his field of view on both eyes simultaneously. The visual symptoms gradually worsened throughout the following 5 months, and the patient was hospitalised in the department of ophthalmology. At this point, his vision had dramatically decreased and visual acuity was measured to 0.05 (1.3 LogMAR) on both eyes. After a thorough medical examination, the patient was diagnosed with an amiodarone-induced toxic optic neuropathy. Regular follow-ups conducted throughout 7 years have shown that the patient's vision has stabilised, but remains limited to the ability of recognising hand motions on both eyes, thus characterising him as blind.
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