Posted on January 13, 2018
The options for removal of glasses, collectively called refractive surgeries, available today are many, and each one of them has a proven track record in terms of both, safety and efficacy.
The options can broadly be categorized into two classes: LASIK and LASIK like laser vision correction, including Advanced Surface Ablations; and the second being intraocular lenses, IOL, including phakic IOLs and clear lens exchange (CLE). The former uses laser to reshape the cornea (the outermost clear, dome shaped part of the eye which is responsible for focusing light on to the retina, along with the natural crystalline lens of the eye). Lens implants are artificial lenses that are fitted inside the eye, either in the space between the iris and the natural crystalline lens (called phakic IOL) or in the space created after removing the natural lens of the eye (called clear lens extraction or refractive lens exchange).
All refractive procedures can achieve 20/20 vision without the need for glasses or contact lenses, safely and effectively, provided they are well suited to the individuals’ eye status and visual needs. Choosing the refractive surgery correctly is the first step in better vision without glasses, and can only be done in conjunction with your eye surgeon, after a thorough comprehensive eye evaluation.
Indications of each procedure and patient selection:
- The following patients are not considered eligible for LASIK: Required level of correction above six to eight dioptres depending on corneal thickness, thin corneas, previous corneal scars or surgeries, corneal grafts, keratoconus etc
- Intraocular lenses can correct very high levels of myopia (up to 20 dioptres) with few patient restrictions. However, less than three dioptres of correction phakic IOLs are not recommended.
- Cataracts are an absolute contraindication for LASIK and phakic IOLs while Refractive lens exchange is the method of choice for patients with early cataractous changes. The same surgery, RLE, is called cataract surgery with IOL implantation, when performed in a patient with visually significant cataract.
- LASIK is less invasive, and the surgeon only operates on the surface of the eye (called an extraocular procedure). However, LASIK involves permanent ablation of some corneal tissue, making the procedure irreversible. LASIK is also significantly faster than a lens implant, and both eyes are operated simultaneously.
- Lens implants are more invasive with the surgeon working on the inside of eye, the procedure is intraocular. Phakic IOLs which do not involve removal of the natural lens of the eye are completely reversible, while CLE is not since in the latter, the natural lens of the eye is removed. Most surgeons prefer to operate each eye on separate days since the procedure carries an increased risk of intraocular infection.
- Lens implants provide additional protection from ultraviolet radiation, a harmful radiation present in sunlight which has been linked with formation of cataracts and age related macular degeneration.
Procedure Duration and Surgical Downtime
The time required in the hospital is the same for both surgeries because of processing of papers and transfers to the operating room. However, LASIK on both eyes is done simultaneously, while certain surgeons prefer to perform lens implants on different days.
- The laser treatment per se takes less than one minute for each eye; total procedure lasts about 15 minutes per eye, after processes to start surgery are complete.
- Lens implants require about 20-30 minutes per eye. Usually, the surgeries for the two eyes are performed about a week apart.
- The time for vision recovery and follow up visit protocols for both goups of surgeries is almost the same.
In case you already need reading glasses, due to presbyopia, an age related decrease in near vision, all refractive procedures cannot address this need.
- In case of LASIK, monovision is possible, in which one eye is corrected for distance vision while the other is corrected for near work.
- Phakic IOLs or Implantable Collamer Lenses, ICL, cannot correct for near vision. Clear lens extraction and refractive lens exchange with multifocal lenses can correct for both, near and distance.
- If you don’t not have presbyopia before the procedure, you will still be able to read without glasses, regardless of the refractive procedure you choose, except if you have a refractive lens exchange with a unifocal lens.
Cost of Procedure
Lens implants are generally more expensive than LASIK. This a is because the lens implant procedure is more invasive and takes longer to perform. There is te additional cost of the lens implant which makes the procedure expensive. However, the costs are comparable to, if not exactly the same as, that of the newly available variants of LASIK including femtosecond LASIK and Relex SMILE.
For patients with low to moderate refractive error and no associated eye diseases, LASIK is the surgery of choice. Refractive lens exchange or lens implants can correct almost any degree of refractive error, and the quality of vision after lens implants is said to be better than after LASIK. That said, RLE usually is performed only if the patient is not a suitable candidate for any other vision correction surgeries like LASIK since it is an invasive procedure, and is more expensive. Phakic IOLs are the best choice for patients of stable keratoconus and for patients post corneal surgeries. For patients with early cataract RLE is the best option.