With LASIK a thin flap of corneal tissue is lifted and the laser correction placed on the underlying corneal bed and the overlying corneal flap then repositioned.

With PRK the correction is placed on the surface of the cornea.

However, the surface of the cornea is covered by a thin layer of clear skin, called epithelium, that if lasered, would grow back and the laser effect negated.

In PRK, but not LASIK, we have to remove this layer of epithelium prior to performing the Laser. Removing the epithelium is painless. However, after PRK there is discomfort until the epithelium heals, which usually takes about 3 days. I put an extended-wear soft contact lens on your eye after PRK, which stays in for 4 to 5 days after PRK, to allow the epithelium to heal faster. In both PRK and LASIK, I have you use antibiotic drops to prevent infection and anti-inflammatory eye drops to decrease discomfort.

I recommend PRK for younger, active patients, for patients with thin corneas, for patients with allergies who may vigorously rub their eyes, and for patients with higher myopic (nearsighted) prescriptions over -5.00 diopters. Presently, I am performing approximately 60 percent PRK and 40 percent LASIK.

If the thought of the flap in LASIK makes you uncomfortable, I would strongly encourage you to consider PRK! PRK is slightly safer and slightly more predictable than LASIK. Also, in my experience, I think the quality of vision is slightly better long term with PRK. The risk associated with the LASIK flap is small, but in 1 to 2 percent of LASIK patients, flap complications occur, but are usually treatable without resultant vision loss. PRK is more uncomfortable (usually watering, light-sensitivity, gritty sensation) than LASIK for 48 to 72 hours post-op.

I think the biggest drawback to PRK is that the vision takes longer to clear after PRK than LASIK. LASIK patients typically return to normal activities 1 to 2 days after surgery; PRK patients are typically blurrier than LASIK patients for about a week after surgery but can usually return to work within 5 days after surgery. Typically, 7 to 10 days after PRK, patients are seeing well enough to function without problem, and by 4-6 weeks the vision after PRK is usually excellent. PRK has a lower retreatment rate (1 to 2 percent vs 5 to 10 percent for LASIK) and may have somewhat less glare and dryness than LASIK. I prefer LASIK in hyperopic (farsighted) patients.

In Summary, both LASIK and PRK give excellent long term results; PRK is marginally safer than LASIK but is more uncomfortable initially and takes slightly longer to heal.