Refractive surgery for high myopia
Andrzej Grzybowski MD
Each of the surgical options for correcting high myopia has a unique set of pros and cons, but only refractive lens exchange (RLE) appears
to be associated with an increased risk of
Speaking at the 18th EURETINA Congress in Vienna, Austria, Andrzej Grzybowski MD, PhD, MBA, reviewed the literature on risk of retinal detachment in high myopes and with cornea and lens-based refractive surgery techniques. He concluded that RLE increases the risk significantly, while phakic IOL implantation does not. Although excimer laser keratorefractive surgery might be excluded from consideration for other reasons, there is no evidence that it increases the risk of retinal detachment, said Dr Grzybowski, Chair of Ophthalmology, University of Warmia and Mazury, Olsztyn, Poland.
According to published reports, the risk of retinal detachment in non-operated myopic eyes ranges between 0.71% and 3.2%. Compared with the general population, the risk of retinal detachment is estimated to be about 50-fold higher in the subgroup with myopia <-15D and 110-fold higher in eyes with myopia >-15D.
“In addition, the risk of retinal detachment in myopes is particularly high during the second, third and fourth decades of life, mainly owing to atrophic retinal holes,” Dr Grzybowski said.
Refractive surgery-related risk
In an article reviewing published data on RLE, Dr Grzybowski and colleagues found that the reported rate of retinal detachment ranged from 0% in some studies to 8.1% in one paper (Alió JL, Grzybowski A, Romaniuk D. Eye Vis (Lond). 2014 Dec 10;1:10.).
“It is quite well known that phacoemulsification itself increases the risk of retinal detachment by 10-fold, and young age is one of the risk factors,” said Dr Grzybowski.
The proposed mechanism involves induction of posterior vitreous detachment, which might occur in close to 80% of highly myopic patients undergoing RLE, he explained.
Traumatic effects resulting from placement of the microkeratome suction ring combined with the shock-wave and thermal effects of the excimer laser create a mechanistic basis for an increased risk of retinal detachment after excimer laser keratorefractive surgery. However, the rate of retinal detachment after LASIK for up to -10D myopia was very low in a study of almost 12,000 eyes (Arevalo JF, Lasave AF, Torres F, Suarez E. Graefes Arch Clin Exp Ophthalmol. 2012;250(7):963-970.).
“Studies comparing PRK and LASIK found no difference between the procedures in the rate of retinal detachment,” Dr Grzybowski said.
Only a few studies evaluated the rate of retinal detachment in myopic eyes that underwent phakic IOL implantation, and they did not find an increased risk, he added.