Influence of a multifocal intraocular lens centration and eye angles on light distortion and ocular scatter index

Criteria for premium intraocular lens patient selection

PURPOSE OF REVIEW

To discuss available premium intraocular lenses (IOLs), patient selection, and important considerations for each premium IOL.

RECENT FINDINGS

We review important topics and considerations for premium IOL selection: specifically, toric, extended depth of focus (EDOF), multifocal/trifocal, light adjustable lenses (LALs), and small aperture IOLs. Toric lenses are an excellent option for patients with astigmatism. However, to achieve optimal patient satisfaction, it is critical to account for the ATR astigmatism contribution from the posterior cornea and high angle alphas. Additionally, examining the ocular surface prior to placement of EDOF/multifocal IOLs is important, yet the significance of HOAs on outcomes after implantation still must be elucidated more. Finally, recent studies reveal that the small aperture lens is a good alternative for those with corneal irregularities, and second generation LALs are a great option to achieve target refractions in those with less predictable refractive outcomes, such as in Fuchs' dystrophy or in eyes with previous refractive surgery.

Clinical and Patient Reported Outcomes of an Optimized Trifocal Intraocular Lens

Background/Objectives: To evaluate the clinical and patient-reported outcomes (PROMs) obtained with an optimized version of a previously investigated trifocal IOL. Methods: Prospective non-comparative single-center study enrolling 29 patients (55-71 years) undergoing bilateral cataract surgery with implantation of the trifocal diffractive IOL Liberty 677CMY (Medicontur Medical Engineering Ltd., Zsámbék, Hungary). Visual and refractive outcomes as well as PROMs were evaluated during a 3-month follow-up: measurement of uncorrected and corrected distance (UDVA, CDVA), intermediate (UIVA, DCIVA) and near visual acuities (UNVA, DCNVA), defocus curve, patient satisfaction, photic phenomena perception, spectacle independence, and difficulty in performing some vision-related activities. Results: A total of 100%, 92%, and 80% of patients achieved a postoperative binocular UDVA, UIVA, and UNVA of 20/25 or better, respectively. Likewise, 100%, 80%, and 84% of patients achieved a postoperative binocular CDVA, DCIVA, and DCNVA of 20/25 or better, respectively. In the defocus curve, all mean visual acuity values were better than 0.15 logMAR for all defocus levels. A total of 95.8%, 95.8%, and 91.7% of patients referred to be satisfied with their distance, intermediate, and near visual vision, respectively. Mean overall Catquest Rasch calibrated score was -3.12 ± 0.98. Most of the patients were spectacle independent: far (95.8%), intermediate (95.8%) or near vision (91.7%). No bothersome or minimal to moderately bothersome halo, starburst, and glare was perceived by 83.3%, 83.4%, and 83.3% of patients, respectively. Conclusions: The trifocal IOL evaluated provides a visual acuity improvement, with high levels of spectacle independence, patient satisfaction, and perceived visual quality associated.

Screening of positive dysphotopsia before multifocal intraocular lens implantation

PURPOSE

To assess the photic phenomena (PP) and positive dysphotopsia in candidates for presbyopia or cataract surgery and to evaluate their relationship with cataract grading systems.

DESIGN

Retrospective observational.

METHODS

Monocular data for 82 subjects measured during the preoperative screening were retrospectively retrieved from our database. The evaluated variables consisted of two methods for PP measurement: light distortion index (LDI) and parameters obtained from a simulator, both of which were combined with subjective bother related to PP. The cutoff for LDI that better predicted patients passing from slightly to moderately bothersome was estimated. The relationships between LDI and the following objective cataract grading methods were also assessed: objective scatter index (OSI), dysfunctional lens index (DLI), and Pentacam Nucleus Staging (PNS).

RESULTS

LDI was the best method for measuring PP, which showed a significant correlation with the bothersome question (rho = 0.34, P = 0.002) and also with OSI (rho = 0.67, P < 0.0005), DLI (rho = -0.29, P = 0.007), and PNS (rho = 0.48, P < 0.0005). The number/percentage of patients who found it bothersome was as follows: "Not at all" (18/22%), "Slightly" (41/50%), "Moderately" (15/18.3%), and "Very" (8/9.7%). The cutoff value that predicted the transition from slightly to moderately bothersome was ≥15.20% according to LDI, which could be estimated with the following values for grading: ≥2.8 for OSI, ≤7.6 for DLI, and ≥2 for PNS.

CONCLUSIONS

Patients reporting moderately or higher bothersome levels in the preoperative period and with LDI <15.20%, <2.8 for OSI, >7.6 for DLI, and <2 for PNS might deserve special attention in the multifocal intraocular lens selection.

Simulations of Multifocal Vision in Patients With Previous Monofocal Intraocular Lens Implantation

PURPOSE

To evaluate the effectiveness and patient acceptance of multifocal vision simulation in patients with previous monofocal intraocular lens (IOL) implantation, and to explore their willingness-to-pay (WTP) and willingness-to-accept (WTA) based on the perceived advantages and disadvantages of multifocal vision.

METHODS

Seventeen patients with previous monofocal IOL implantation participated in this cross-sectional study. The SimVis Gekko device (2EyesVision SL) was used to simulate monofocal (Evaluation B) and multifocal (Evaluation C) visual experiences, compared to their existing vision (Evaluation A). Visual acuity at three distances and defocus curves were measured. Patients responded to inquiries about visual quality in each evaluation, bothersomeness of photic phenomena, probability to select the visual experience, and the monetary value they associated with enhanced WTP or diminished WTA visual quality.

RESULTS

The simulations underestimated the visual acuity reported for the IOL in existing literature by one or two lines, depending on the testing distance. This underestimation was more pronounced in defocus curves. However, 70.6% of patients were likely or very likely to opt for multifocal vision, indicating they perceived the benefits of multifocality. The WTP for multifocal vision was twice that of monofocal vision, and the WTP/WTA ratio exceeded 1, suggesting the perceived vision benefits outweighed potential drawbacks.

CONCLUSIONS

Despite underestimating the expected postoperative visual performance, the multifocal simulation enabled patients to perceive the benefits of multifocal vision to some extent. This system could be beneficial in avoiding potential postoperative complaints, but the possible rise in false-positive results should be considered and evaluated in future research. [J Refract Surg. 2023;39(12):831-839.].