Which laser vision correction would have less chance of complication such as hazy vision after surgery: Lasik or PRK?
PRK Vs. Lasik
Doctor Answers (10)
The Difference Between PRK and LASIK
- LASIK is usually our procedure of choice, given the quick and painless visual recovery. The safety profile of LASIK has increased significantly since the advent of the femtosecond lasers. Flap complications are very rare.
- Some patients may not be the best candidates for LASIK, and PRK (flapless lasik) may be recommended. Situations when PRK is preferable include: thin corneas, corneal scars, corneal shape irregularity. Studies show that when you compare the quality of vision 1 month after the procedure, PRK and LASIK result in very comparable, excellent quality of vision.
- In the past when LASIK was done with mechanical keratomes one had to consider the risk of having a flap complications (LASIK) vs. the risk of possible PRK haze. With the advent of flying spot EXCIMER lasers like the Wavelight Allegretto and use of adjuvants like mitomycin, PRK haze has become very uncommon.
PRK Versus LASIK: Pros and Cons
It may be hard to believe these days, when everything is "LASIK this" and "LASIK that," but PRK (photorefractive keratectomy) used to be the most common refractive surgery procedure.
Both are grouped under the umbrella "laser eye surgery," but each is a little different when it comes to advantages and disadvantages.
LASIK patients have less discomfort and obtain good vision more quickly (with PRK improvement is gradual and over a few days or even months), but many surgeons prefer PRK for patients with larger pupils or thin corneas. Dr. Drucker is one of these surgeons, and, in fact, is a PRK specialist.
PRK was invented in the early 1980s. The first FDA approval of a laser for PRK was in 1995, but the procedure was practiced in other countries for years. In fact, many Americans had the surgery done in Canada before it was available in the United States.
PRK is performed with an excimer laser, which uses a cool ultraviolet light beam to precisely remove ("ablate") very tiny bits of tissue from the surface of the cornea in order to reshape it. When you reshape the cornea in the right way, it works better to focus light into the eye and onto the retina, providing clearer vision than before.
Both nearsighted and farsighted people can benefit from PRK. With nearsighted people, the goal is to flatten the too-steep cornea; with farsighted people, a steeper cornea is desired. Also, excimer lasers can correct astigmatism by smoothing an irregular cornea into a more normal shape.
Complication rate of LASIK vs PRK
I am a believer that these two procedures are equally safe provided, obviously, that they are performed well and that patient selection is appropriate. Some patients with thin corneas, for example, are better candidates for PRK. Others, with very high prescriptions, are more suited for LASIK. Performing either one on the "wrong" patient can lead to side effects, including haze. This fact emphasizes the pivotal importance of choosing a surgeon that has the integrity to choose his/her procedures wisely and, most importantly, has the wisdom to tell a patient they are not a candidate for either procedure if that is the case.
These are both extremely safe procedures, actually, in my opinion, safer than wearing contact lenses. They do however, necessitate a thorough preoperative workup, good patient education and elegant surgical skill during the procedure.
You might also like...
Safety: PRK versus LASIK
PRK has a lower chance of complications than traditional LASIK.
However Intra-LASIK and PRK are both so safe that it is difficult to compare. Both are among the safest procedures in existence. Comparable to dental surgery in safety or laser hair removal.
Intra-LASIK and PRK are both similar to getting a laser treatment in your cornea, which is the fastest healing area of the body, faster than your skin.
Haze can be a complication of some PRK procedures
Corneal haze has long been a complication of PRK. With the newer lasers and medications used during and after surgery to modulate healing it is much less common than it has been. The newer lasers create a smoother ablation and this substantially reduces the risk of complications. Most surgeons now use a drug called Mitomycin that reduces the chance of haze substantially. Patients can do their part as well. Avoid pregnanacy for the first few months. Substantial changes in hormonal status substantially increases the risk of haze. The use of UV protecting sunglasses for a year after your procedure is also important, even on a cloudy day. Lastly, many surgeons believe that the consumption of one gram of Vitamin C per day for the first year is also helpful.
LASIK has less chance of haze post operatively
LASIK has less chance of haze post operatively. iLASIK, which is the most advanced LASIK technology has the best chance of superior vision as it is the most accurate and precise procedure.
Hazy vision and corneal haze
Hazy vision can be from many things including swelling, infiltrates, refractive error, internal eye problems and corneal haze.
Corneal haze is a medical term where the clear cornea becomes somewhat opaque and this can interfere with vision in some cases. This type of haze was common after PRK due to the healing response but is much less likely due to newer and better lasers and medical treatment after the PRK procedure. A major change is the usage of Mitomycin C off label to reduce post operative corneal haze.
Haze can also occur with LASIK, although due to the location of the treatment, it is much less likely than with PRK and thus the Mito C is not required.
Again, patients complaints of hazy vision needs to be distinguished from true corneal haze which is a medical condition.
About Lasik or PRK complication: Hazy vision, corneal haze, and LASIK
"Hazy vision" does not necessarily equal corneal haze. As the two previous MDs have already noted, corneal haze (a loss of clarity of the cornea, the front part of the eye) can occur with any corneal surgery, though it is extremely rare with LASIK, and very rare now with PRK thanks to the adjunctive (intraoperative) use of a medication called Mitomycin-C. Corneal haze is a euphamism for scarring.
Hazy vision, on the other hand, might have several possible causes post-LASIK. Certainly corneal haze or scarring can cause hazy vision. Dryness of the eye can give a sensation of haziness, as can corneal edema or swelling which is common in the weeks following LASIK and PRK.
Also, residual refractive error (nearsightedness, farsightedness, and astigmatism) can make the vision hazy, though it more typically causes blurring. Some people may actually say their vision is hazy but they really mean it's blurry. Hazy vision can also mean a reduction in what is known as "contrast sensitivity." This has to do with the optical quality of the eye, and the effect of optical aberrations such as spherical aberration on your visual perception. Things that wavefront LASIK help reduce, or keep neutral. As these aberrations increase, which typically occurs with non-wavefront LASIK, there is more of a burden on your brain to filter them out to keep your vision from being perceived as "hazy."
And finally, other non-corneal problems can lead to hazy vision. This would include cataract, and retinal troubles. Glaucoma, an elevation of pressure in the eye, if acute can lead to swelling of the cornea and hazy vision.
LASIK vs PRK
Haze is now less common withthe advent of new laser technologies and the use of mitomycin C. PRK has the advantage of being a safer procedure than LASIK. There are no flap complications, less dry eye problems, and less night vision problems. LASIK does offer a much faster return to vision.
Haze more common with PRK than LASIK
Haze or a slight clouding of the cornea, or the outer surface of the eye, is a complication more commonly associated following PRK. With newer lasers and medicines to prevent haze, this is not commonly seen in 2008. The risk of haze to the cornea is less often noted with LASIK. However, it is important to discuss the risks as well as the benefits of these procedures with your laser vision specialist to determine which procedure is best for you!
These answers are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.
You might also like...
Ask a Doctor
Get personalized answers from board-certified doctors. For free.