Consequences of inadvertent intravitreal Mitomycin C injection

Mitomycin C (MMC) as an alkylating agent is miscellaneous an antineoplastic, antibiotic and ophthalmic agent. Here we aim to report a case of inadvertent intravitreal MMC injection instead of Avastin in case of diabetic macular edema.

A 53 years old woman was planned to receive intravitreal Avastin injection, but accidentally, 0.05 ml of MMC 0.2% was injected. Best corrected visual acuity (BCVA) was 20/160 before injection. After 2 days, patient was referred to a tertiary referral eye center. BCVA was hand motion at presentation. Intraocular pressure was 4 mmHg. In slit lamp exams, conjunctival injection, corneal edema, Descemet fold, anterior chamber and anterior vitreous cells were presented. Pars plana vitrectomy with peripheral vitreous shaving and silicone oil tamponade was performed. Electroretinography showed undetectable responses. Ultrasound biomicroscopy showed ciliary body shortening and detachment. Optical coherent tomography showed diffuse retinal edema the day after surgery, subretinal fluid pockets in 2 weeks, and atrophy with undetectable and intertwined layers 2 months later. Gradually, like the retina, iris became atrophic and pigments were dispersed diffusely over the lens and endothelium.

MMC is showed to be severely toxic to intraocular tissues. In our case, iris and ciliary body became atrophic. Ciliary body detachment induced hypotony. Moreover, MMC induces retinal necrosis and atrophy. Visual outcome is profoundly poor.