With such a wealth of lengthy and professional terminology, it’s no wonder that many candidates for laser eye surgery are puzzled at the different treatment options. It’s also quite possible that one can qualify for several different types of surgery, and that in this case, a patient may request one particular method over another (subject to approval by their ophthalmologist, of course).
In this article, the main differences between the three most popular types of laser eye surgery will be explained, which are Conventional PRK, Trans-epithelial PRK, and LASIK.
PRK is well-known for being the first of its kind: the original laser eye treatment. In comparison to older methods, Conventional PRK was revolutionary, as this technique provided a far less invasive procedure to correct the most common visual imperfections such as astigmatism, farsightedness (hyperopia) and nearsightedness (myopia).
The entire procedure is quite brief. After prepping for surgery – which includes using anaesthetic eye drops – the epithelium (the thinnest, outermost layer of the cornea) is gently removed, either with an alcohol agent, or manually. Then, laser pulses are used to reshape the curved cornea to correct irregularities.
Post-treatment, the epithelium will regenerate itself completely within 5 or so days. During this time, you will visit your ophthalmologist frequently in order to keep tabs on the healing process. You will be prescribed antibiotic eye drops to help speed up the healing process, however as the epithelium is completely removed, most find that complete healing takes longer in comparison to other treatments.
With advances in technology, Trans-epithelial PRK has emerged as an even less invasive PRK procedure, yet the underlying treatment is the same. The epithelial layer and the stroma are removed during this type of surgery, however, as its name suggests, they are removed in a single, swift step with a laser – and no other instruments are used during the entire operation.
The recovery process for Trans-epithelial PRK is a little faster than compared to Conventional PRK, partly due to the “hands-free” nature of the operation. Clarity of vision appears to return faster and there may be a little less post-operative discomfort.
The term LASIK is an acronym for Laser in situ Keratomileusis. It differs greatly from Conventional PRK and Trans-epithelial PRK in that it does not involve the removal of any part of the epithelial layer, or the stroma, in order to reshape the cornea.
Rather than removing or disintegrating the eye’s delicate epithelial layer, a tiny incision is made – either via laser or with a scalpel, which leaves a “flap”‘ or opening in the epithelium. This thin flap is gently lifted up, allowing the laser beams to smooth and shape the cornea underneath. The procedure generally takes around five minutes or so for each eye.
In comparison with Trans-epithelial and Conventional PRK, LASIK appears to have the least overall post-operative complications, and the fastest recovery. This is because the minute incisions in the outer layers heal more rapidly in comparison to removal of the epithelial layer.