Which refractive procedure predates excimer-laser methods?

Which refractive procedure predates excimer-laser methods?

• A. Radial Keratotomy
• B. Photorefractive Keratotomy
• C. LASIK
• D. Phakic IOL

Answer: (A)

Radial keratotomy predates excimer-laser methods because it achieves refractive change with mechanical corneal incisions rather than laser ablation. Surgeons made radial cuts in the cornea to flatten its shape and correct myopia, a technique used well before excimer lasers were developed for corneal reshaping. Photorefractive keratectomy and LASIK rely on the excimer laser to remove tissue and reshape the cornea, which came into wide use later. Phakic intraocular lenses alter vision by implanting a lens rather than reshaping the cornea, and they were introduced after laser-based corneal procedures. So the earliest procedure among these is radial keratotomy.

Radial keratotomy predates excimer-laser methods because it achieves refractive change with mechanical corneal incisions rather than laser ablation. Surgeons made radial cuts in the cornea to flatten its shape and correct myopia, a technique used well before excimer lasers were developed for corneal reshaping. Photorefractive keratectomy and LASIK rely on the excimer laser to remove tissue and reshape the cornea, which came into wide use later. Phakic intraocular lenses alter vision by implanting a lens rather than reshaping the cornea, and they were introduced after laser-based corneal procedures. So the earliest procedure among these is radial keratotomy.