sulfur mustard exposure and non-ischemic central retinal vein occlusion

a 41-year-old man was referred with a complaint of visual loss in his left eye and his best corrected visual acuity was 20/80. slit lamp examination showed arborizing conjunctival vessels and dry eye. fundus examination and fluorescein angiography revealed a non-ischemic central retinal vein occlusion. cardiovascular, rheumatologic, and hematologic work up showed no abnormal findings. an ascertained history of exposure to sulfur mustard during the iran-iraq war was documented in his medical history. four sessions of intravitreal bevacizumab injections were done as needed. after two-year follow-up, visual acuity in his left eye improved to 20/25 and macular edema was resolved without any need for further interventions. we conclude that sulfur mustard gas exposure may be considered as a predisposing factor for central retinal vein occlusion, as was found in our patient (an iranian war veteran) by excluding all yet known etiologies and predisposing factors.