A 28-year-old patient wants LASIK surgery. Corneal topography shows inferior steepening with an asymmetric bowtie pattern and posterior elevation of +18 μm above the best-fit sphere. The correct clinical interpretation and management decision is:
- A Normal topography; proceed with LASIK
- B Forme fruste keratoconus; LASIK is contraindicated, refer for corneal collagen crosslinking evaluation ✓
- C Regular myopic astigmatism; LASIK can be performed after spectacle correction trial
- D Contact lens warpage; discontinue contact lenses and repeat in 4 weeks
Correct answer: B. Forme fruste keratoconus; LASIK is contraindicated, refer for corneal collagen crosslinking evaluation
Explanation
Inferior corneal steepening with asymmetric bowtie pattern on Placido topography combined with elevated posterior elevation (>12–15 μm above the best-fit sphere) on Scheimpflug imaging (Pentacam) is characteristic of forme fruste (subclinical) keratoconus. LASIK is absolutely contraindicated as it will weaken the already ectatic cornea and precipitate iatrogenic keratectasia post-surgery. Management involves close monitoring and corneal collagen crosslinking (CXL) if progression is documented. PRK (surface ablation) is also generally avoided in suspected ectasia.
Reference: Khurana Comprehensive Ophthalmology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.