A patient develops pseudophakic bullous keratopathy 5 years after extracapsular cataract surgery with anterior chamber IOL implantation. The primary mechanism of corneal decompensation is:

• A Intraoperative phototoxicity to corneal endothelium
• B Posterior corneal dystrophy accelerated by surgery
• C Elevated IOP causing endothelial pump failure
• D Chronic contact and mechanical trauma to corneal endothelium by IOL haptics ✓

Explanation

Pseudophakic bullous keratopathy (PBK) following anterior chamber IOL (AC-IOL) placement results from chronic mechanical trauma and contact between the IOL haptics/optic edge and the corneal endothelium. AC-IOLs lie in close proximity to the endothelium, especially if oversized; haptic pressure on angle structures causes endothelial cell loss over time through direct contact injury and uveitis-glaucoma-hyphema (UGH) syndrome. This progressive endothelial cell loss eventually falls below the critical threshold (~500 cells/mm²), precipitating stromal oedema and bullous keratopathy. Management requires IOL exchange and penetrating or DSAEK keratoplasty.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.