A patient with an intraocular foreign body (IOFB) from a metallic hammer-and-chisel injury requires management. The IOFB is 3 mm copper fragment in the vitreous visible on B-scan. The urgency is related to the specific toxic reaction caused by copper, which is:
- A Siderosis — iron ion-mediated oxidative damage to photoreceptors
- B Chalcosis — deposition of copper compounds in ocular tissues causing Kayser-Fleischer ring, sunflower cataract, and retinal degeneration ✓
- C Lead toxicity — optic neuropathy and ERG changes
- D Zinc toxicity — RPE disruption without anterior segment changes
Correct answer: B. Chalcosis — deposition of copper compounds in ocular tissues causing Kayser-Fleischer ring, sunflower cataract, and retinal degeneration
Explanation
Copper IOFBs cause chalcosis, where copper ions disseminate throughout the eye, depositing in Descemet's membrane (Kayser-Fleischer ring), lens capsule (sunflower cataract), and retina (macular degeneration, abnormal ERG). Pure copper (>85%) causes an acute sterile endophthalmitis-like reaction, while copper alloys cause slow chalcosis. Urgent surgical removal is mandatory. Siderosis is caused by iron-containing IOFBs with rust-colored iris and ERG amplitude reduction. Chalcosis is specific to copper.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.