Comparison of Predictability Using Barrett Universal II and SRK/T Formulas according to Keratometry. (19th June 2020)

• Record Type: Journal Article
• Authors: Iijima, Kei; Kamiya, Kazutaka; Iida, Yoshihiko; Shoji, Nobuyuki
• Other Names: Lansingh Van C. Academic Editor.
• Is Part Of: Journal of ophthalmology. Volume 2020(2020)
• Publication Date: 2020-06-19
• Subjects: Ophthalmology -- Periodicals; Eye Diseases; Ophthalmology; Ophthalmology; Electronic journals; Periodicals; Periodicals; Fulltext; Internet Resources; Periodicals; 617.7
• DOI: 10.1155/2020/7625725
• Languages: English
• ISSNs: 2090-004X

Abstract

Abstract : Purpose . To compare the predictability of intraocular lens (IOL) power calculation using the Barrett Universal II and the SRK/T formulas, according to the keratometry. Methods . We retrospectively reviewed the clinical charts of 335 consecutive eyes undergoing standard cataract surgery. IOL power calculations were performed using the Barrett Universal II and the SRK/T formulas. We compared the prediction error, the absolute error, and the percentages within ±0.25, ±0.5, and ±1.0 D of the targeted refraction, 1 month postoperatively, and also investigated the relationship of these outcomes with the keratometric readings, using the two formulas. Results . The prediction error using the SRK/T formula was significantly more myopic than that using the Barrett Universal II formula (the paired t -test, p < 0.001 ). The absolute error using the SRK/T formula was significantly larger than that using the Barrett Universal II formula (p = 0.006 ). We found a significant correlation between the prediction error and the keratometric readings using the SRK/T formula (Pearson correlation coefficient, r = −0.522, p < 0.001 ), but there was no significant correlation between them using the Barrett Universal II formula ( r = −0.031, p = 0.576 ). Conclusions . The Barrett Universal II formula provides a better predictability of IOL power calculation and is less susceptible to the effect of the corneal shape, than the SRK/T formula. The Barrett Universal formula, instead of the SRK/T formula, may be clinically helpful for improving the refractive accuracy, especially in eyes with steep or flat corneas.