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Updated: Jun 20, 2025
Author Spotlight: Advancements in Refractive Surgical Correction for Presbyopia and Exploring Postoperative Visual Acuity
Published on: September 20, 2024
Effect of Belin-Ambrósio deviation index on 2-year refractive outcomes of PRK
Seyyed Saeed Shams1, Samira Hassanzadeh, Mehran Zarei-Ghanavati
1From the Student Research Committee, Islamic Azad University, Mashhad Branch, Mashhad, Iran (Shams); Department of Optometry, School of Paramedical Sciences and Rehabilitation, Mashhad University of Medical Sciences, Mashhad, Iran (Hassanzadeh); Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran (M. Zarei-Ghanavati); Department of Community Medicine, Mashhad Branch, Islamic Azad University, Mashhad, Iran (Ravanshad); Eye Research Center, Mashhad University of Medical Sciences, Mashhad, Iran (Sadeghi, S. Zarei-Ghanavati); Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand (Ziaei).
Purpose:
To assess the effect of preoperative Belin-Ambrósio deviation (BAD-D) index on 2-year visual, refractive, and tomographic outcomes, as well as the efficacy and safety of photorefractive keratectomy (PRK) surgery.
Setting:
Eye clinic, Mashhad, Iran.
Design:
Prospective cohort study.
Methods:
This study included 66 patients (66 eyes) who underwent PRK surgery, with a minimum follow-up period of 2 years. Participants were divided into 2 groups: preoperative BAD-D ≥1.60 (high BAD-D) and preoperative BAD-D <1.60 (low BAD-D). Preoperative and postoperative visual, refractive, and tomographic parameters were evaluated, and the efficacy and safety of the procedure were compared between groups.
Results:
66 patients with a mean age of 35.50 ± 8.21 years (range 22 to 55 years) were included. Postoperatively, the mean spherical equivalent (SE) of refractive error was +0.32 ± 0.65 diopters (D) in the high BAD-D group and +0.18 ± 0.66 D in the low BAD-D group ( P = .40). In addition, at 2 years of follow-up, the mean uncorrected distance visual acuity was 0.98 ± 0.07 in the high BAD-D group and 0.97 ± 0.08 in the low BAD-D group ( P = .905). Among the postoperative tomographic parameters, front elevation thickness, maximum Ambrósio relational thickness, astigmatism, and central corneal thickness were significantly different between the 2 groups (all, P < .05). At the 2-year follow-up, the mean Safety Index was 1.02 ± 0.04, and 1.01 ± 0.04 in high and low BAD-D groups, respectively ( P = .37), and the mean Efficacy Index was 0.99 ± 0.07 and 0.98 ± 0.06 in high and low BAD-D groups, respectively ( P = .40).
Conclusions:
The preoperative BAD-D index does not predict postoperative visual, refractive, and tomographic outcomes in patients with low-to-moderate myopia. However, in patients with normal preoperative BAD-D values, higher agreement was expected between the attempted and achieved SE.
