Vision loss and methamphetamine use

A 57‐year‐old man presented to the emergency department with a 2‐day history of painless vision loss in his left eye. He had a history of smoking tobacco and methamphetamine, with increased methamphetamine use over the previous week. He had no history of hypertension, dyslipidaemia or diabetes. Visual acuity was 6/6 in the right eye and count fingers in the left eye. He had a left relative afferent pupillary defect, and on fundoscopy there were widespread flame haemorrhages and cotton wool spots (Figure, B, arrow), suggestive of an ischaemic central retinal vein occlusion. In the right eye, he also had some flame haemorrhages and a cotton wool spot (Figure, A, white arrow) inferior to the macula, suggestive of a small area of branch retinal vein occlusion. A sclerosed branch retinal vein extending from the inferonasal part of the right optic nerve (Figure, A, black arrow) was also visible, suggestive of a previous (presumably long‐standing) branch retinal vein occlusion. Methamphetamine‐induced ocular complications include severe corneal ulceration and scarring, keratitis, episcleritis, scleritis, crystalline retinopathy, central retinal artery occlusion, ischaemic retinopathy, and retinal vasculitis.1,2 The sympathomimetic effects of methamphetamine, which might induce extensive vasoconstriction or vascular spasm,2 are believed to be the cause of ischaemic central retinal vein occlusion.