Crystalline deposits in the retina may be associated with a wide variety of systemic disorders such as oxalosis, cystinosis, hyperornithinaemia and Sjogren-Larsson syndrome. Refractile crystalline deposits may also be a manifestation of drug toxicity like the antineoplastic agent tamoxifen, the anesthetic methoxyflurane and the oral tanning agent canthaxanthine. Crystals may also occur in drug abusers who inject multiple crushed tablets of methadone or meperidine intravenously (talc retinopathy).