Posters

Analysis of excimer laser treatment outcome and corresponding angle kappa in hyperopic astigmatism

Poster Details

First Author: E.Bigdon GERMANY

Co Author(s):    A. Frings   S. Linke   J. Steinberg   T. Katz           

Abstract Details

Purpose:

To investigate the prevalence of pre-, intra- and postoperative Angle Kappa (AK) in hyperopic eyes and its impact on refractive outcome of Excimer Laser vision correction.

Setting:

University Hospitals Düsseldorf and Hamburg and Care Vision Refractive Centers, Germany.

Methods:

Retrospective multicenter study. Hyperopic patients after LASIK prior to retreatment due to hyperopic regression were included. Three treatment groups were defined based on the magnitude of preoperative AK defined as low <0,25, moderate 0,25 to 0,50, or high >0,50 mm.

Results:

170 hyperopic eyes of 112 patients (mean age 29,8 ±10,04, range 21 to 62 years) were analyzed. Preoperative AK was low, moderate or high in 23, 49 and 98 cases, respectively. In eyes with a preoperative AK of 0,25mm and more, changes of AK´s x/y-axes and its magnitude were statis-tically significant (P<0,05) between pre- and intraoperative measurements. In these eyes, in-traoperative AK (offset) was statistically significantly (P<0,05) smaller, Purkinje images were statistically significantly (P=0.00) more caudal. Treatment predictability was independent from using pre- or intraoperative AK and no statistically significant differences in efficacy or safety were obtained.

Conclusions:

A preoperative magnitude of AK as high as 0.50 or higher is present in more than 50% of re-gressed hyperopic eyes. Measuring AK preoperatively does not reflect its real time intraoperative magnitude. Using the preoperatively larger AK as intraoperative offset may result in a too nasal-ly centered ablation which causes topographic and optical drawbacks. We recommend centering the ablation based on the intraoperative measured offset.

Financial Disclosure:

None