Optic Neuropathy following Botulinum Toxin Injection into the Medial Rectus Muscle for Diplopia

Purpose: To report a case of optic neuropathy (ON) following botulinum toxin A (BTA) injection into the medial rectus muscle. Case Report: We describe a 37-year-old man with unilateral ON after a BTA injection into the left medial rectus for treatment of traumatic sixth nerve palsy. Oral prednisolone was prescribed for 14 days. After two weeks, his visual acuity returned to 20/20. Conclusion: Botulinum toxin-induced neuropathy is a rare and vision-threatening complication of BTA. In patients with recent injection of BTA who present with visual complaints, botulinum toxin-induced neuropathy should be considered