Abstract
Purpose :
A glasses prescription is often readily available at the pre-operative cataract evaluation visit. The Holladay2 intraocular lens (IOL) power prediction formula permits entry of such a refraction as an added variable. The purpose of this study was to investigate the predictive accuracy of the Holladay2 formula with and without use of this optional variable.
Methods :
Retrospective consecutive case series of eyes that underwent routine phacoemulsification cataract surgery with implantation of a one-piece acrylic monofocal IOL performed, or supervised by, a single surgeon at an academic medical center between February 2016 and June 2018. Exclusion criteria included prior surgery in the operative eye, another procedure performed concurrently at the time of cataract surgery, absence of a pre-operative glasses prescription on record, or a best-corrected post-operative visual acuity worse than 20/40. An optical biometer was used to measure each eye, and the Holladay2 formula, with and without input of the eye’s pre-operative glasses prescription, was used to calculate predicted post-operative spherical equivalents. Outcome measures included mean prediction error (MPE), absolute MPE, and proportion of eyes achieving a post-operative refraction within 0.5 D of predicted. Student’s t-test was used to compare the paired data.
Results :
In the 179 eyes that met criteria for inclusion in the analysis, the MPE with and without use of the pre-operative glasses prescription was 0.03 and 0.05 D, respectively (p = 0.12). Absolute MPEs were 0.40 and 0.37 D, respectively. The proportion of eyes achieving a post-operative spherical equivalent within 0.5 D of predicted was 69.3 and 74.8%, respectively (p = 0.29). Optimization of the formula did not alter these results significantly.
Conclusions :
There is a trend toward improved refractive outcomes of cataract surgery when the most recent glasses prescription is omitted from the Holladay2 formula. Larger scale studies are warranted to determine whether this trend is statistically significant, and how the Holladay2 formula may be optimized.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.