Kelvin H Wan1, Thomas C H Lam2, Marco C Y Yu3, Tommy C Y Chan4. 1. Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong. 2. Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Hong Kong Eye Hospital, Hong Kong. 3. Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Department of Mathematics and Statistics, Hang Seng Management College, Hong Kong. 4. Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong; Department of Ophthalmology, Hong Kong Sanatorium and Hospital, Hong Kong. Electronic address: tommychan.me@gmail.com.
Abstract
PURPOSE: To compare the accuracy and precision of the new Hill-RBF version 2.0 (Hill-RBF 2) formula with other formulas (Barrett Universal II, Haigis, Hoffer Q, Holladay 1, and SRK/T) in predicting residual refractive error after phacoemulsification in high axial myopic eyes. DESIGN: Retrospective case series. METHODS: 127 eyes of 127 patients with axial length (AL) ≥26 mm were included. The refractive prediction error (PE) was calculated as the difference between the postoperative refraction and the refraction predicted by each formula for the intraocular lens (IOL) power actually implanted. Standard deviation (SD) of PE, median absolute PE (MedAE), proportion of eyes within ±0.25, ±0.50, and ±1.00 diopter (D) of PE were compared. A generalized linear model was used to model the mean function and variance function of the PE (indicative of the accuracy and precision) with respect to biometric variables. RESULTS: The MedAE and SD of Hill-RBF 2 were lower than that of Hoffer Q, Holladay 1, and SRK/T (P ≤ .036) and were comparable to Barrett Universal II and Haigis (P ≥ .077). Hill-RBF 2 had more eyes within ±0.25 D of the intended refraction (76 out of 127 eyes [59.84%]) compared to other formulas (P ≤ .034) except Barrett Universal II (P = .472). AL was associated with the mean function or variance function of the PE for all formulas except Hill-RBF 2. CONCLUSIONS: In this study, the precision of Hill-RBF 2 is comparable to Barret Universal II and Haigis. Unlike the other 5 formulas, its dispersion and the accuracy of the refractive prediction is independent of the AL.
PURPOSE: To compare the accuracy and precision of the new Hill-RBF version 2.0 (Hill-RBF 2) formula with other formulas (Barrett Universal II, Haigis, Hoffer Q, Holladay 1, and SRK/T) in predicting residual refractive error after phacoemulsification in high axial myopic eyes. DESIGN: Retrospective case series. METHODS: 127 eyes of 127 patients with axial length (AL) ≥26 mm were included. The refractive prediction error (PE) was calculated as the difference between the postoperative refraction and the refraction predicted by each formula for the intraocular lens (IOL) power actually implanted. Standard deviation (SD) of PE, median absolute PE (MedAE), proportion of eyes within ±0.25, ±0.50, and ±1.00 diopter (D) of PE were compared. A generalized linear model was used to model the mean function and variance function of the PE (indicative of the accuracy and precision) with respect to biometric variables. RESULTS: The MedAE and SD of Hill-RBF 2 were lower than that of Hoffer Q, Holladay 1, and SRK/T (P ≤ .036) and were comparable to Barrett Universal II and Haigis (P ≥ .077). Hill-RBF 2 had more eyes within ±0.25 D of the intended refraction (76 out of 127 eyes [59.84%]) compared to other formulas (P ≤ .034) except Barrett Universal II (P = .472). AL was associated with the mean function or variance function of the PE for all formulas except Hill-RBF 2. CONCLUSIONS: In this study, the precision of Hill-RBF 2 is comparable to Barret Universal II and Haigis. Unlike the other 5 formulas, its dispersion and the accuracy of the refractive prediction is independent of the AL.
Authors: Laura Gutierrez; Jane Sujuan Lim; Li Lian Foo; Wei Yan Ng; Michelle Yip; Gilbert Yong San Lim; Melissa Hsing Yi Wong; Allan Fong; Mohamad Rosman; Jodhbir Singth Mehta; Haotian Lin; Darren Shu Jeng Ting; Daniel Shu Wei Ting Journal: Eye Vis (Lond) Date: 2022-01-07