Keratometry Prediction Accuracy in SCHWIND AMARIS 1050 after Myopic Laser Correction
Seyed Hashem Daryabari1 *, Khosrow Jadidi2 , Hesam Hashemian3
- Assistant Prof. of Ophthalmology, Chemical Injury Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran
- Department of Ophthalmology, Baqiyatallah University of Medical Sciences, Tehran, Iran
- Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
Abstract: Introduction: The SCHWIND AMARIS 1050RS is a new eye laser system for corneal refractive surgery. It also estimates post-operative keratometry before laser ablation. Post-operative keratometry is one of the influential factors that can change the outcome of Photorefractive keratectomy (PRK). This study aimed to compare Schwind's predicted keratometry results with post-operative keratometry six months after myopic PRK.
Methods: In this cross-sectional study, patients with myopia less than -10.00 Diopters and astigmatism less than 5.00 Diopters were admitted for PRK. They were excluded if they had any previous ocular surgery or comorbidities. Schwind AMARIS 1050RS predicts Post-operative keratometry when refraction is inserted Before laser ablation. Keratometric values, sphere, cylinder, and SE were recorded Before and six months after laser ablation,
Results: This study included 60 eyes of 30 patients (16 female and 14 male) with a mean age of 28.56 ± 6.1 years (Range 21 to 45 years) PRK was done for both eyes in all patients. The difference between predicted mean keratometry and Post-operative mean keratometry was 0.19 diopter, and the intraclass correlation coefficient (ICC) test average measure showed 0.98 (P-value ˂ 0.001). The ICC test was used for different ages, keratometry, and spherical equivalent (SE) between predicted mean keratometry and Post-operative mean keratometry, and it showed a range between 0.98 to 0.91 (P-value ˂ 0.001).
Conclusion: Pre-operative Keratometry prediction by SCHWIND AMARIS 1050RS has high accuracy in different conditions. The conventional formula is a powerful instrument for keratometry prediction, but we need a more complicated procedure for high myopic patients.
