January is a time where people tend to make resolutions to maybe lose weight, stop smoking, etc. but some people will be finally making the resolution to get their vision corrected by more than just glasses or contact lenses. Of course, any kind of vision correction requires a detailed and thorough consultation by an eye clinic and ophthalmologist to check suitability, but here we will look at the 3 most common types of vision correction.
Laser Vision Correction
Laser vision correction, or LVC, is probably the most common vision correction method when people initially start researching about getting their eye sight corrected. There are various types of laser vision correction and machines to carry it out, but the main to procedures are LASIK (Laser-Assisted in situ Keratomileusis) and LASEK (Laser-Assisted Subepithelial Keratomileusis).
With the LASIK procedure, a femtosecond laser is used to create a flap on the cornea. The flap then is opened like the page of a book to expose tissue just below the cornea’s surface. Next, the excimer laser is used to remove ultra-thin layers from the cornea to reshape it to reduce nearsightedness, farsightedness and/or astigmatism. Finally, the flap is returned to its original position.
During the LASEK procedure instead of a femtosecond laser creating a flap, a dilute solution of alcohol in placed within a ring on the cornea, this softens the top cells of the cornea which are then gently pushed over to one side. Again, the excimer laser is used to remove ultra-thin layers from the cornea to reshape it to reduce nearsightedness, farsightedness and/or astigmatism. The remaining cells are then pushed back onto the cornea and a bandage contact lens is applied to the surface of the eye to facilitate healing of the epithelium and which will be removed at the first follow up appointment.
Implantable Contact Lens
Implantable contact lenses, or ICLs, medically called phakic IOL lens implants, can be used if someone is unsuitable for laser vision correction, this may be due to prescription, shape of the cornea, or pupil size, amongst many other reasons. There are two main types of ICLs, behind the iris or in front of the iris (iris clip). With both procedures the implantable lenses have a power which corrects the prescription.
The most common type of ICL is behind the iris as you are unable to see the lens within the eye. During behind the iris ICL surgery the ophthalmologist makes a small incision between the white and coloured part of the eye, the incision is only a few millimetres, then the lens is implanted through the incision. The lens is folded up within a cartridge and as it is being implanted will start to unfold within the eye behind the iris and then it will be manoeuvred into place. With iris clip ICLs a small incision will be made between the white and coloured part of the eye again. This time the lens is implanted through the incision but on top of the iris. There are clips on either side of the lens which are clipped to the iris once the lens is in the correct position.
Refractive Lens Exchange
Refractive lens exchange, or RLE, surgery replaces the natural clear lens (or with very early cataract, preventing the natural lens developing a more advanced cataract) with an artificial intraocular lens to correct vision. It is especially good for people with high myopia or presbyopia (natural aging of the eye) and is a better alternative to laser vision correction in older people. It is also an option where laser vision correction is not indicated or not able to correct vision such as in young people with high levels of long-sightedness.
The usual technique to remove the natural lens is called phaco-emulsification. A tiny incision is made between the white and coloured part of the eye. Then the natural lens is softened with ultrasound through the incision and removed through a small tube. The artificial lens is then implanted into the eye, which is supported by a bag of lens tissue (capsule). The lens implant stays in the eye permanently.
There are various types of artificial lenses that can be implanted into the eyes to correct vision; a monofocal lens implant will correct distance vision only, monovision using monofocal lens implants will correct one eye for distance and one eye for reading, and premium lens implants such as multifocal and trifocal lenses will correct both eyes the same for distance, near and intermediate.
All three procedures above are normally carried out while the you are awake, but the eye has been completely numbed so you won’t feel anything, and they are all quite quick procedures.
Remember to always do your research when considering having any kind of vision correction and always visit a reputable eye clinic or ophthalmologist to discuss your options.