PRK - Trans PRK
You would like to get rid of your glasses? It’s now possible with laser technology.
You need to have a full eye examination. During this exam, a precise evaluation of your refractive error (myopia, hyperopia, astigmatism, presbyopia) will be performed.
In addition, the shape of your cornea will be evaluated using specific instruments (topography, tomography, aberrometry, pachymetry, corneal hysteresis). Those exams are very easy to perform and take 5 mn per examination without any contact with your eye.
The interview with the eye surgeon is essential in order to evaluate your need and discuss the best option for your condition so you can benefit from a customized/personalized treatment.
Myopia, hyperopia and astigmatism can be corrected with PRK with excellent results. The main difference with LASIK is the longer recovery time with PRK because it takes a few days for the new epithelial layer to regenerate and cover the surface of the cornea. The second main difference is higher discomfort (tearing, burning and itching sensation) in the first 2 days after PRK as compared to LASIK surgery.
The main benefit of PRK is sparing corneal tissue because there is no corneal flap as in LASIK. Thus it’s indicated for thin corneas in which LASIK surgery might be contra-indicated. Post-operative corneal dryness can occur after LASIK or PRK however, it’s more moderate after a PRK.
Refractive Surgery - PRK
Like LASIK, Photorefractive Keratectomy (PRK) works by reshaping the cornea using an excimer laser, allowing light entering the eye to be focused on the retina.
In PRK the outer layer of the cornea (epithelium) is removed (manually or with the laser (TransPRK) and the underlying tissue (stroma) is reshaped with the excimer laser. The epithelium grows back over the corneal surface within few days after the surgery.
Surgery occur under local anesthesia so anesthetic drops are instilled inside your eyes to prevent any pain during the procedure. A specific instrument is positioned to keep your eyes open and avoid blinking. You will be asked to fixate a target light for a short time while the laser is in action.
The preparation for the surgery takes 15 mn, while surgery itself takes few seconds.
After the surgery, burning, itching and tearing might begin and will remain for the first 24 to 36 hours (during the epithelial healing period). During that time, it’s normal to have a blurry vision. Vision will start to improve after 3 days and will keep improving 4 to 6 weeks after the surgery.
At 3 months, vision after PRK is usually as good as after a LASIK procedure.
Refractive Surgery - Trans-PRK
Transepithelial PRK is a no touch, one step laser only treatment for myopia, hyperopia, and astigmatism. Compared to PRK, many patients find there is a speedier recovery. Compared to LASIK, Transepithelial PRK does not require an additional procedure to create a flap in order to expose the layer where laser treatment is applied.
Under local topical anesthesia (drops), Transepithelial PRK uses a laser to remove a thin layer of cells (corneal epithelium) which naturally grow back after surgery. Transepithelial PRK is therefore preferred over LASIK in patients with a thinner cornea.
You will be asked to look at a blurry light. Once you're ready, the laser treatment is applied. Once complete, drops and a temporary contact lens are applied to allow the eye to heal.
The post-operative course is very close to the one described above after a PRK, with slightly faster healing and less pain.