Scientific Program
PGT4
Author Membership Number:
03243A
Author Name:
Dr.Samarpita Dhar
Presenting Author
MEMBERSHIP NO
AUTHOR NAME
EMAIL
MOBILE
03243A
Dr.Samarpita Dhar
[email protected]
7000682325
Title:
Accuracy of intraocular lens power calculation formula in patients with high myopia in Central India
Synopsis:
Objective: To compare the accuracy of four IOL power calculation formulae (Barrett Universal II, SRK/T, Holladay 1, and Holladay 2) in patients with axial lengths (AL) > 26 mm undergoing cataract surgery. Design: Prospective observational clinical study. Methodology: The study included 43 eyes from highly myopic patients. Preoperative biometry (AL, K, ACD, LT, WTW) was performed using the SS-OCT-based IOL Master 700. Phacoemulsification with foldable IOL implantation was performed, and stable postoperative refraction was recorded at 6 weeks. Statistical Analysis: Data were analyzed via IBM SPSS 22. The Kruskal-Wallis test compared Mean Absolute Errors (MAE) across four AL subgroups (26–27 mm, 27.01–28 mm, 28.01–29 mm, and 29.01–30 mm), and the Friedman test compared the four formulae. Results: The mean AL was 27.27 ± 1.17 mm. Barrett Universal II demonstrated the highest accuracy with the lowest overall MAE (-0.122 D) and 67% of eyes within ±0.50 D of target. SRK/T followed with an MAE of -0.173 D. Holladay 2 and Holladay 1 were less accurate, with MAEs of -0.509 D and -0.585 D, respectively. Accuracy for SRK/T and Holladay formulae significantly declined as AL increased, whereas Barrett remained consistent across all subgroups. Conclusions: The Barrett Universal II formula is the most reliable for IOL power calculation in high myopia (AL > 26 mm). While SRK/T is acceptable for moderate ALs, newer generation formulae like Barrett Universal II, paired with SS-OCT biometry, are essential to minimize hyperopic surprises and optimize visual outcomes in extremely long eyes.
