Abstract
Purpose::
To investigate refractive, morphological and optical changes induced by Lasik surgery for hyperopia by measuring refractive results, keratorefractive indices and corneal aberrations.
Methods::
90 hyperopic eyes that underwent hyperopic lasik using an Hansatome microkeratome (Baush&Lomb) and the Technolas 217Z (Baush&Lomb) excimer laser have been evaluated. Corneal topography was performed with Eye-Top (CSO). Mean preoperative cycloplegic refraction was 3,44 +- 1,16 D. Mean preoperative pupillary power was 43,48 +- 6,14 D. Refraction, UCVA, BCVA, Mean pupillary power, Asphericity, Surface Asimmetry Index (SAI), Curvature irregularity have been recorded. Total, cylinder, spherical, coma and HO aberrations have been measured using RMS value for a 5 mm pupil size preoperatively and at 1 year.
Results::
Postoperatively: SAI was 1,81 D (std = 2,04); the mean average root mean square (RMS) of total aberrations was 1,30 µm (std 0,64); for spherical aberrations was -0,55 µm (std = 0,90); LSA 0,10 µm (std = 0,18); for coma -0,89 µm (std = 1,60); for HO 0,13 µm (std = 0,20). Corneal aberrations increased after hyperopic treatment; spherical aberration was shifted in negative direction.
Conclusions::
Lasik hyperopic treatment induced an increase in corneal aberrations. Evaluation of corneal aberrations can be helpful to evaluate the refractive surgery outcome.
Keywords: hyperopia • refractive surgery • optical properties