ESCRS - PO717 - Evaluating The Impact Of Angle Kappa On Effective Optical Zone In Kerato-Lenticule Extraction (Klex) Surgery With Intraoperative Angle Kappa Adjustment

Evaluating The Impact Of Angle Kappa On Effective Optical Zone In Kerato-Lenticule Extraction (Klex) Surgery With Intraoperative Angle Kappa Adjustment

Published 2025 - 43rd Congress of the ESCRS

Reference: PO717 | Type: Free paper | DOI: 10.82333/pt46-a568

Authors: Hamza Khorsheed 1 , Ahmed Sermed Al Sakini 2 , Fadi Alzraikat 1 , Irfan Ullah 3 , Omar Hossain 4 , Mohammed A. Fenjan* 5

1Jordanian University of Science and Technology,Amman,Jordan, 2Department of Ophthalmology ,University of Baghdad, College of Medicine,Baghdad,Iraq, 3Department of Internal Medicine,Bacha Khan Medical College,Mardan,Pakistan, 4University of Western Ontario,Ontario,Canada, 5Department of ophthalmology,Ibn Al Haitham Teaching Eye Hospital,Baghdad,Iraq;Department of Ophthalmology ,University of Baghdad, Alkindy College of Medicine,Baghdad,Iraq

Purpose

The impact of angle kappa on the postoperative effective optical zone (EOZ) in kerato-lenticule extraction (KLEx) surgery remained inconclusive. This study aimed to investigate the influence of preoperative angle kappa on postoperative EOZ in KLEx patients with intraoperative angle kappa adjustment.

Setting

Taipei Chang Gung Memorial Hospital

Methods

A retrospective study was conducted on 174 eyes from 89 myopic patients who underwent KLEx with small incision lenticule extraction (SMILE) procedure with intraoperative angle kappa adjustments was included. Preoperative angle kappa (µ) was defined as the chord distance between the pupil center and corneal vertex. The study cohort was divided into two groups: large angle kappa (µ > 0.2mm, n = 84) and small angle kappa (µ ≤ 0.2mm, n = 90). EOZ parameters, including EOZ area, decentration, and eccentricity, were measured at one month postoperatively. Linear regression analyses were performed to assess the relationships between preoperative angle kappa and postoperative EOZ parameters.

Results

Postoperatively, EOZ area, major and minor axis, decentration, and eccentricity did not differ significantly between groups. Univariate linear regression revealed significant but modest negative correlation of angle kappa with EOZ area and minor axis (adjusted R² = 0.02 and 0.03; P = 0.03 and 0.02, respectively). Further multiple regression incorporating spherical equivalent demonstrated that angle kappa was not a significant predictor of EOZ parameters.

Conclusions

In conclusion, our study showed that preoperative angle kappa had minimal effect on EOZ parameters in KLEx surgery when appropriate intraoperative adjustments for angle kappa were implemented.