Photo-Refractive Keratectomy

Photo-Refractive Keratectomy (PRK) was the first-ever laser refractive surgical technique introduced in the eighties for the corneal surface remodeling. Although PRK has been the most commonly practiced Excimer Laser refractive surgery procedure across the world for decades, it gained its first medical approval as a safe, suitable and effective laser refractive correction technique from the FDA in 1995. In the US, PRK is widely performed on professionals in military and defense services.

Several surgical evidences and case studies also claim that the PRK surgery is performed widely on patients having low to high levels of myopia and astigmatism. In addition, PRK is also a better surgical procedure for hyperopic patients. Following this surface remodeling technique, the corneal surface is either flattened (for myopic) or smoothened out from irregularities (for astigmatic) or curved out (in hyperopia). Hence, patients get better and clearer vision e.g. 20/40 vision. With the rapid developments in other more sophisticated methods such as LASIK and LASEK, the PRK technique is now becoming quite outdated and is used mostly to correct low refractive errors. In some cases, surgeons perform PRK on patients who have thinner corneas or larger pupils.

There are differences in opinions among ophthalmologists worldwide regarding the safety profile of PRK. Some potential risk factors of the PRK include

·    Patients may experience mild discomfort, eye irritation and watering for 1-3 days in the post-operative period.

·    The healing process of the cornea is not as fast as the LASIK or LASEK procedures.

·    PRK patients usually takes a longer time to achieve the best corrected vision ( up to 3 months after surgery in normal circumstances).

·    Sometimes patients may require glasses to achieve best vision.

·    Patients may experience other visual discomforts such as minor glares, mild halos and haze around images or in the dimly lit surroundings.   

Various medical reports confirm that the PRK is as safe and effective as LASIK and LASEK, yet the visual recovery process is much slower than the latter Excimer laser surgeries. Therefore, PRK techniques need better evaluations to live up the patient’s expectations and providing them a satisfying and long term vision correction. Several experiments have been conducted so far, and many are on the run to determine how and to what extent the PRK can be made safer and a more effective laser refractive surgery. PRK is not recommended for patients with medical records of glaucoma, thinning cornea, dry eyes, cataracts and eye infections. Moreover, those who are suffering from diabetes, immunity related ailments, multiple sclerosis or rheumatoid arthritis are not advised to undergo PRK.