Excimer laser photorefractive keratectomy (PRK) in myopic astigmatism.

UNLABELLED: To assess the visual and refractive results of excimer laser photorefractive keratectomy (PRK) in myopic astigmatism.

METHODS: Excimer laser PRK was performed using an Aesculap Meditec MEL 60 laser in 46 myopic astigmatic eyes. Preoperative corneal astigmatism was -1.50 D. (+/- 0.50) in 7 eyes (15.2%); -2.50 D. (+/- 0.50 in 14 eyes (30.5%); -3.50 D. (+/- 0.50) in 13 eyes (28.3%); -4.50 D. (+/- 0.50) in 8 eyes (17.4%); and -5.50 D. (+/- 0.50) in 4 eyes (8.6%). Mean preoperative cylinder was -3.50 D. (+/- 2.50). Mean preoperative sphere was -4.50 D. (+/- 2.25). Pre and post-operative visual acuity, refraction, keratometer readings, corneal topography, intraocular pressure, and slit lamp findings were recorded.

RESULTS: By one year of follow-up, postoperative cylinder was between +0.50 and -0.50 D. in 31 eyes (67.4%); between -0.50 and -1.50 D. in 11 eyes (23.9%); between -1.50 and -2.50 D. in 4 eyes (8.7%). Mean post-operative cylinder was -1.21 D. (+/- 1.70). Mean postoperative sphere was -1.09 D. (+/- 1.25). Myopic and astigmatic improvement was achieved in each patient (100%). Topography analysis showed 69.4% were within 0.5 mm, 96.8% within 1 mm, 97.8% within 1.5 mm of centration; 55% of the patients achieved uncorrected visual acuity of 10/10 (Snellen). One patient (2.2%) lost one line of best corrected vision due to decentration and change of axis.

CONCLUSION: These preliminary results of myopic astigmatic excimer laser PRK procedures compare favorably in efficiency and safety with reports of PRK for myopia.