Influence of pupil dilation on predicted postoperative refraction and recommended IOL to obtain target postoperative refraction calculated by using third- and fourth-generation calculation formulas

Abstract

PurposeTo evaluate the influence of pupil dilation on predicted postoperative refraction (PPR) and recommended intraocular lens (IOL) power to obtain target postoperative refraction calculated by using the third- and fourth-generation IOL power calculation formulas with a new optical biometer.MethodsThis retrospective study included 162 eyes with cataract that underwent uneventful phacoemulsification with IOL implantation. PPR, recommended IOL power, anterior chamber depth (ACD), and lens thickness (LT) were measured pre- and post-pupil dilation. The change in PPR detected by using third-generation (Hoffer Q and SRK/T) and fourth-generation formulas (Haigis and Holladay 2) and the changes in ACD and LT were evaluated pre- and postdilation. The influence of dilation on the recommended IOL power calculated by each formula was analyzed.ResultACD and LT significantly changed from pre- to postdilation. The mean absolute change in PPR between pre- and postdilation was significantly higher for fourth-generation formulas compared with third-generation formulas. The change in PPR between pre- and postdilation showed a significantly positive correlation with change in ACD and a significantly negative correlation with change in LT with fourth-generation formulas, but not with third-generation formulas. The discrepancy rate of recommended IOL power between pre- and postdilation calculated by fourth-generation formulas was significantly higher than that calculated by third-generation formulas.ConclusionACD and LT significantly changed by dilation. PPR and recommended IOL power significantly changed more by dilation when using fourth-generation formulas compared with third-generation formulas. Given the significant correlations of the change in PPR (between the pre- and postdilation) in the fourth-generation formulas and the changes in ACD and LT, the latter changes may be key in influencing dilation in the fourth-generation power calculation. Knowledge of the influence of dilation on fourth-generation formulas could help improve IOL calculation.

Influence of pupil dilation on the Barrett universal II (new generation), Haigis (4th generation), and SRK/T (3rd generation) intraocular lens calculation formulas: a retrospective study

“…In our study, while ACD significantly increased after dilation, LT significantly decreased, which are both consistent with previous research [16]. WTW did not significantly change.…”

“…Effective lens position is estimated based on ACD and AL in Haigis [2], and Barrett Universal II uses AL, corneal curvature radius, ACD, LT, and WTW [3]. Several studies have investigated the influence of pupil dilation on these biometric measurements [8,[10][11][12][13][14][15][16]. In a clinical setting, pupil dilation is a vital process of preoperative examination.…”

Agreement of ocular biometric measurements in young healthy eyes between IOLMaster 700 and OA-2000

“…Our results were in good accordance with those previously reported between the OA-2000 and Lenstar 16 and between the Lenstar and IOLMaster 700 17 . Although LT was not used as a variable in the calculation of IOL power previously, the fourth-generation formula such as Olsen has taken this into account 18 . Therefore, the impact of LT difference on the refractive prediction error of pseudophakic eye may not be negligible in the new-generation formulas for IOL power calculation, and further studies are needed.…”

Comparison of the influence of pupil dilation on predicted postoperative refraction and recommended intraocular lens power among Barrett Universal II, Haigis, and SRK/T calculation formulas: a retrospective study

“…Universal II changed most frequently among the formulas, although it was not statistically significant between Barrett Universal II and Haigis. Although some studies demonstrated that the recommended IOL power in Haigis was significantly affected by pupil dilation but not in SRK/T 10),12), 16) , our research was the first to show that Barrett Universal II may be even more sensitive to pupil dilation than Haigis, considering PPR and recommended IOL power. Haigis and SRK/T.…”

“…In our research, while ACD significantly increased after dilation, LT significantly decreased, which are consistent with other studies. 16) WTW did not significantly change. When it comes to the influence of pupil dilation on PPR and recommended IOL power, the outcomes of past research vary from formula to formula and from research to research.…”