Skip to main content

Refractive surgery questions and MCQs for residents

Refractive surgery, BCSC Section 13, covers the optics of refractive error and wavefront aberrations, corneal biomechanics and imaging, patient evaluation, and the full range of procedures: photorefractive keratectomy and other surface ablations, LASIK, small-incision lenticule extraction, incisional corneal surgery, intracorneal ring segments, corneal cross-linking, phakic intraocular lenses, refractive lens exchange and presbyopia correction. It also addresses refractive surgery in eyes with coexisting ocular or systemic disease.

Boards concentrate on candidacy and safety. Expect topography and tomography maps to be read for forme fruste keratoconus or pellucid marginal degeneration, reasoning about residual stromal bed thickness and ectasia risk, and complications identified by their timing and appearance: diffuse lamellar keratitis versus central toxic keratopathy versus infectious keratitis, epithelial ingrowth, flap striae and post-LASIK ectasia. Items on IOL calculation and IOP measurement after corneal refractive surgery link this section to cataract and glaucoma.

Use these refractive surgery MCQs to rehearse the preoperative checklist until it is reflexive, then use the explanations and decision flowcharts to separate look-alike postoperative complications. Spaced repetition and weak-topic drills help retain the optics principles and contraindications that recur across exams.

Free refractive surgery practice questions

Refractive surgery questions are in the OphthoMentor app: create a free account to practise them with explanations, flowcharts and spaced-repetition review.

High-yield refractive surgery topics for boards

  • Preoperative evaluation: refractive stability, contact lens holiday, dry eye, pupil size
  • Topography and tomography: forme fruste keratoconus, inferior steepening, posterior elevation
  • Pellucid marginal degeneration: crab-claw topography, against-the-rule astigmatism
  • Ectasia risk factors: abnormal topography, thin residual stromal bed, young age
  • Munnerlyn formula: ablation depth, optical zone diameter and attempted correction
  • Wavefront aberrations: Zernike polynomials, spherical aberration, coma from decentration
  • Contraindications: corneal ectasia, uncontrolled autoimmune disease, pregnancy, unstable refraction
  • LASIK flap complications: buttonhole, free cap, striae, dislocation
  • Epithelial ingrowth: risk factors, flap lift enhancement, indications for removal
  • Diffuse lamellar keratitis staging versus central toxic keratopathy versus infection
  • Post-LASIK infectious keratitis: early gram-positive versus late atypical mycobacteria
  • Pressure-induced stromal keratitis: steroid response with underestimated IOP after LASIK
  • Post-PRK haze: risk factors and mitomycin C prophylaxis
  • Small-incision lenticule extraction versus LASIK: flapless technique, enhancement options
  • Corneal cross-linking: riboflavin-UVA mechanism, indications, corneal thickness requirement
  • Astigmatic keratotomy and limbal relaxing incisions: the coupling effect
  • Radial keratotomy legacy: diurnal fluctuation, progressive hyperopic shift
  • Phakic IOLs: endothelial cell loss, cataract, pigment dispersion, angle closure
  • Presbyopia correction: monovision, multifocal and extended-depth-of-focus IOLs
  • IOL power calculation after LASIK, PRK and radial keratotomy

How refractive surgery is examined

Refractive surgery corresponds to BCSC Section 13. On the OKAP and ABO written examinations, items often combine a clinical vignette with a topography or tomography map, or with a refractive outcome that must be explained, so the tested skill is judgment about candidacy and complications rather than surgical technique alone. Clinical optics underpins many stems, including aberrations, ablation depth and anisometropia.

The EBO Diploma and FRCOphth written papers test the same principles, particularly patient selection, risks relevant to consent, recognition of post-LASIK complications and the implications of prior refractive surgery for later cataract surgery and IOP measurement. Questions frequently cross over with cornea (keratoconus, cross-linking) and with lens and cataract (refractive lens exchange, IOL calculation after keratorefractive surgery).

In orals, refractive surgery tends to appear as a counseling or complication scenario: assessing an unsuitable candidate, explaining halos after surgery or managing interface inflammation in the first postoperative days. A structured approach of history, examination, imaging, contraindications and options transfers directly from written items to spoken answers.