Abstract
Purpose:
Evaluate the refractive results from two months onward, had a focus group of patient who was able to benefit trans-PRK for ametropia.
Methods:
Trans-epithelial PRK, whereas regular PRK, uses laser for the ablation of the corneal epithelium and is not operated manually. The retrospective study includes 70 patients (129 eyes) who undergo surgery for myopia, astigmatism and hyperopia by Trans-PRK (Excimer Schwind Amaris 500E) between April 2012 and October 2013. The auto-refraction measures preoperative and postoperative were realized by an auto-refractometer (Luneau L67). The study parameters were: preoperative and final refractions after 2 months (based on a spherical equivalent) compared with intended refraction initially researched. For a majority of the patients, the targeted refraction was emmetropia, excepted for the youngest myopics patients for which the targeted refraction was +0.25 D. For fifteen presbyopics patients, a final residual myopia between -0.50 and -2.00D were deliberately sought at the master eye.
Results:
Our study is focusing on 129 eyes from 70 patients (43 females, 27 males) with a middle age population of 38.3 ±13.7 years old. Patients presented myopia, hyperopia or astigmatism. The ametropia population was considered as the norm, with a maximal hyperopia of +4D and a maximal myopia of -8D. The average basis of corrected myopia were -2.52 ±1.47D, hyperopia one’s of +2.58 ±1.05D, finally astigmatism one’s 1.58± 1.09D. On all 96 eyes intended emmetropia or intended at +0.25D, 64% (61 eyes) had postoperative acuity of 20/20 and 98% (94 eyes) had acuity of 20/40 or better uncorrected. The mean deviation from intended correction is 0.455± 0,39D at 2 months (in absolute value), and is not correlated to the type of ametropia. The mean manifest refractive spherical equivalent was ≤0.25D for 52% of the eyes (66) and ≤0.50D for 81% of the eyes (104).
Conclusions:
Treatments by transPRK are currently not well developed, lacking adapted equipment in most of the healing centers. Refractive results bring satisfaction with a mean deviation from intended correction of 0.45D, regardless the initial ametropia, which is conform and equivalent to the results after regular PRK in the literature data. The transPRK procedure appears as a simple, fast, uniform and non-operator-dependent method for a refractive result which appears equivalent to the one obtained through the regular PRK surgical intervention.
Keywords: 686 refractive surgery: PRK •
482 cornea: epithelium