For which procedures are Excimer or halide lasers commonly used?

• A. Photocoagulation and thermal therapy
• B. PRK and LASIK
• C. Endoscopic surgeries
• D. Soft tissue repair

Answer: (B)

Excimer and halide lasers are particularly well-suited for refractive eye surgeries, specifically procedures like PRK (Photorefractive Keratectomy) and LASIK (Laser-Assisted In Situ Keratomileusis). These lasers emit ultraviolet light which is highly effective at precisely reshaping the cornea by removing microscopic layers of tissue without causing thermal damage to surrounding areas. This precision is crucial in these types of surgeries, as the goal is to correct refractive errors such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism.

In PRK, the outer layer of the cornea is removed, and then the excimer laser is used to reshape the underlying corneal tissue. In LASIK, a flap is created in the cornea, and the laser is used beneath the flap to reshape the cornea, after which the flap is repositioned.

The other procedures listed, while they may utilize different laser technologies or methodologies, do not typically involve excimer or halide lasers in the same manner. Photocoagulation and thermal therapy involve different types of lasers and techniques, while endoscopic surgeries typically use CO2 lasers or other modalities. Soft tissue repair generally does not involve exc