A 70-year-old patient with Fuchs' endothelial dystrophy undergoes Descemet membrane endothelial keratoplasty (DMEK) rather than penetrating keratoplasty. The primary advantage of DMEK over full-thickness PK is:
- A DMEK replaces full-thickness stroma providing greater structural support
- B DMEK is easier to perform technically and is preferred in low-volume centres
- C DMEK selectively replaces only the diseased Descemet's membrane and endothelium with faster visual recovery, lower rejection rates, and preservation of host corneal structure ✓
- D DMEK provides better correction of irregular astigmatism from stromal scarring
Correct answer: C. DMEK selectively replaces only the diseased Descemet's membrane and endothelium with faster visual recovery, lower rejection rates, and preservation of host corneal structure
Explanation
DMEK involves transplanting a thin scroll of donor Descemet's membrane and endothelium (~10–15 µm thick) without accompanying stroma. Advantages over PK include: faster visual rehabilitation (often 6/9 or better within 1–3 months), significantly lower immune rejection rate (< 1% vs 10–20% for PK), no suture-related complications, and preservation of recipient corneal biomechanics. Technical difficulty (manipulation of the extremely delicate graft) is a recognised disadvantage, not an advantage. PK is preferred for stromal scarring.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.