Influence of pupil dilation on predicted postoperative refraction and recommended IOL power in monofocal and bifocal IOLs to obtain target postoperative refraction calculated by 3rd- and 4th-generation IOL power calculation formulas
Session Details
Session Title: Presented Poster Session: Cataract Surgery Outcomes
Venue: Poster Village: Pod 1
First Author: : T.Teshigawara JAPAN
Co Author(s): : A. Meguro N. Mizuki
Abstract Details
Purpose:
To evaluate the influence of pupil dilation on predicted postoperative refraction (PPR) and recommended IOL power in monofocal (SN60WF, Alcon) and bifocal (ZLB00, AMO) IOLs to obtain target postoperative refraction calculated by the 3rd- (Hoffer Q and SRK/T) and 4th- (Haigis and Holladay2) generation IOL power calculation formulas using a new optical biometer (IOL Master 700, Carl Zeiss Meditec). Its effect on anterior chamber depth (ACD) and lens thickness (LT), and the correlation between all influences was analyzed.
Setting:
Yokohama Tsurumi Chuoh Eye Clinic and Yokosuka Chuoh Eye Clinic, Kanagawa, Japan
Methods:
This retrospective study used 234 eyes (164 SN60WF and 70 ZLB00). PPR, recommended IOL power, ACD and LT were measured pre- and post-dilation. PPR and recommended IOL power were calculated by 3rd- and 4th-generation formulas. Mean absolute change (MAC) between pre- and post-dilation in PPR in each formula and mean change between pre- and post-dilation in ACD and LT were evaluated. Correlation between all changes was analyzed. Dilation’s influence on recommended IOL power calculated by each formula was analyzed. All analyses were done in both monofocal and bifocal IOLs. BellCurve for Excel used for analysis.
Results:
MAC between pre- and post-dilation in PPR in 4th-generation (monofocal: 0.0385; bifocal: 0.0431) was significantly higher than in 3rd-generation (monofocal: 0.0061; bifocal: 0.0064)(p<0.0001). ACD and LT significantly changed between pre- and post-dilation (p<0.0001). Change between pre- and post-dilation in PPR in 4th-generation showed positive correlation with change in ACD (p<0.0001) and negative correlation in LT (p<0.0001), but not in 3rd-generation. Recommended IOL power calculated by 4th-generation changed between pre- and post-dilation in 15.4% of monofocal IOL and 20.0% of bifocal IOL, whereas 3rd-generation showed no or few changes in recommended IOL power between pre- and post-dilation (monofocal: 0.6%; bifocal: 0.0%)(p<0.0001).
Conclusions:
PPR and recommended IOL power in monofocal and bifocal IOLs were significantly changed by dilation in 4th-generation compared to the ones in 3rd-generation. ACD and LT were significantly changed by dilation. Given the significant correlation between the change in PPR pre- and post-dilation in 4th-generation and the change in ACD and LT pre- and post-dilation, it suggests the change of ACD and LT is key in the influence of dilation on 4th-generation. Conversance to dilation’s influence on 4th-generation is key to improve IOL calculation in both monofocal and bifocal IOLs.
Financial Disclosure:
NONE
