LASIK vs. Phakic IOLs
Written by Dr. David Evans Last modified on September 20, 2018
As the popularity of phakic IOLs increases comes increased confusion over whether it’s a better vision correction option than LASIK. Both procedures can help patients achieve 20/20 vision without the need for glasses or contact lenses, but these are two very different procedures that correct vision in very different ways.
The LASIK procedure uses a laser to remove tissue from the cornea to correct vision. This procedure can correct very low to very high amounts of defocus from 0.5 diopters up to 10 or more. (Some studies show excellent LASIK results for patients up to 18 diopters.) But the major restricting factor in how much correction can be achieved with LASIK is corneal thickness. The higher the correction, the more corneal tissue has to be removed. For patients with a very high degree of myopia, the cornea may simply not be thick enough to obtain the full correction.
Phakic IOLs on the other hand do not require the removal of corneal tissue; vision is corrected by placement of a lens inside the eye. The two different types of phakic IOLs — Visian and Verisyse — work a little differently in terms of where they are placed in the eye, but both work the same way by combining the correction of the implanted lens with the natural lens to achieve 20/20 vision (or better).
The biggest difference between LASIK and phakic IOLs is that LASIK cannot be performed on a substantial number of patients whose required level of correction is above six diopters, due to the corneal thickness. Alternatively, phakic IOLs can correct very high levels of myopia (up to 20 diopters) with few patient restrictions. However, on the lower end of the spectrum (below three diopters of correction) no phakic IOLs are available to accommodate this low level of correction; so LASIK is the only potential option.
If you need between three and 10 diopters of correction, then you may have a choice of LASIK or phakic IOLs for vision correction since both may be used to correct this level of blur. If you fall within this category, these comparative bullet points may be helpful.
- LASIK Is less Invasive, but requires the removal of corneal tissue and cannot be reversed (i.e. once the corneal tissue is gone it cannot be replaced).
- Phakic IOLs require the surgeon to enter the inner part of the eye to place the lens, making this procedure more invasive than LASIK. But, it can be reversed (i.e. the surgeon can re-enter the eye and remove the lens).
- Both procedures have very low complication rates.
- Both procedures combine with the focusing power of the natural lens, so if you don’t not have presbyopia before the procedure, you will still be able to read without glasses.
- Phakic IOLs are more expensive than LASIK. Typically $3,000 to $5,000 per eye versus $1,5000 to $2,000. This added expense is because the procedure is more invasive and takes longer to perform, and because there is a cost for the lens. Although both procedures take less than 15 to 20 minutes.
- Both procedures give patients an immediate improvement in vision.
- Some studies show that LASIK patients have a higher incidence of dry eye after treatment than phakic IOL patients. Just as with any type of eye surgery, those with phakic IOLs are not immune from potential dry eye complications.
- Phakic IOLs are used primarily to treat myopia, though new lenses (called Toric lenses) are now available to treat certain ranges of astigmatism.
- LASIK can be used to treat myopia, astigmatism or hyperopia.
In summary, LASIK is the best procedure for patients with low-to-medium myopia while phakic IOLs are better suited for patients with medium-to-high myopia. For those patients in the middle who could have either procedure, a discussion with your eye surgeon can help determine which procedure may best suit your vision needs.