Abstract
Purpose :
This study aimed to determine the longitudinal variability of intraocular lens (IOL) measurements. There is little consensus regarding the time interval during which IOL measurements appear to be reliable or consistent. If there is significant variability in measurements over time, utilizing outdated scans may lead to unanticipated refractive error postoperatively. However, if this longitudinal variation in measurements does not exist, unnecessarily recapturing measurements would waste patient and physician time and resources.
Methods :
A retrospective study was conducted utilizing the Lenstar LS900 and Atlas Topography 9000 databases within University Ophthalmology Associates, an Ophthalmology clinic at Rush University Medical Center in Chicago, Illinois. Patients between the ages of 55 and 90 who had undergone 2 sets of ocular biometry and topography, at least 3 months apart, were included. Biometry variables, such as axial length, corneal thickness, aqueous depth, anterior chamber depth, lens thickness, flat meridian, and steep meridian, as well as topography variables, such as flat and steep keratometry, were included. Changes in recommended IOL power and theoretical postsurgical refractive error, calculated using the Hoffer Q, Holladay I, SRK/T, Olsen, Barrett, and Hill RBF formulations were also examined. A linear mixed effect model with random intercept was applied to determine if there were significant differences between the measurements.
Results :
A total of 100 subjects (200 eyes) were included in this analysis. When comparing the two sets of measurements captured by the Lenstar LS900 and Atlas Topography 9000, only a significant difference in lens thickness (p = 0.026) was appreciated. There were no significant differences observed in recommended IOL power or theoretical postsurgical refractive error using the Hoffer Q, Holladay I, SRK/T, Olsen, Barrett, and Hill RBF formulations.
Conclusions :
Current dogma warns against utilizing outdated IOL measurements for cataract extraction with IOL implantation. However, no significant differences exist in recommended IOL power or theoretical postsurgical refractive error between measurements captured at least 3 months apart. Thus, clinical significance of such principles is limited.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.