Abstract
Purpose :
For the image quality control of intraocular lenses (IOLs), ISO 11979-2 standard recommends the usage of small (2 to 3 mm) apertures for monofocal designs and both small and large (4 to 5 mm) apertures for multifocal ones. Historically, monofocal and multifocal IOL designs from different manufacturers were characterized by various amounts of pupil dependent optical behavior. JJSV developed IOL designs whose image quality is characterized by progressively higher pupil independence. In this context, for selected monofocal and multifocal designs, the current study evaluates the predictive reliability of 5 mm Modulation Transfer Function (MTF) metric for small apertures.
Methods :
A large sample of TECNIS monofocal (ZCB00) and TECNIS Synergy (ZFR00V) IOLs was used for the evaluation of image quality in quality control conditions. Optical bench measurements were performed in an ISO11979-2 model eye 2 (c(4,0) = 0.27 micrometers). MTF at FAR was recorded for both 3 and 5 mm pupils and 546 nm wavelength. For each lens model and figure of merit, statistical evaluations were conducted to assess the measurements capability as well as their reliability to detect failed IOLs. Additionally, a correlation analysis by means of 2D histograms was conducted.
Results :
For both lens models and MTF FAR metrics the standard deviations were ≤ 0.02 MTF units. Furthermore, the distance from the average to the specification limit for MTF at FAR with 5 mm was higher than 6.0 deviation units. For both lens models, for the 5 mm FAR metric the critical value corresponds to > 99.9% reliability for detecting failed IOLs with 95% confidence. For both lens models, the correlation analysis between the two MTF metrics evidenced a statistically significant (p < 0.05) and positive correlation.
Conclusions :
For lens model TECNIS monofocal and TECNIS Synergy, the MTF at FAR with a 5 mm pupil is predictive for and more sensitive to variations than MTF at FAR with 3 mm pupil. Therefore, for specific lens designs, since the 5 mm measurement is a worst-case test condition, the addition of small pupil measurement is not relevant for IOL image quality control. Hence, for specific monofocal and multifocal IOL designs the ISO 11979-2 requirements for image quality control might be considered generic.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.