Stability of a Novel Intraocular Lens Design: Comparison of Two Trifocal Lenses

Epidemiology and Burden of Astigmatism: A Systematic Literature Review

SIGNIFICANCE

This is the first literature review to report the epidemiology, patient burden, and economic burden of astigmatism in the general adult population. The unmet needs of astigmatism patients with coexisting ocular conditions (cataract, glaucoma, dry eye, presbyopia, or macular degeneration) and risks associated with untreated astigmatism are also reviewed and reported.

PURPOSE

This study aimed to identify, report, and summarize the published literature on epidemiology, patient burden, and economic burden of astigmatism using a systematic literature review.

METHODS

MEDLINE, EMBASE, and Cochrane Library databases were searched (January 1996 to May 2021). Search results were limited to the English language. Proceedings (2018 to 2021) from ophthalmology congresses were searched along with gray literature using the Google Scholar platform.

RESULTS

The literature search yielded 6804 citations, of which 125 met the inclusion criteria (epidemiology, 68; patient burden, 60; economic burden, 6). Astigmatism prevalence in the general population varied from 8 to 62%, with higher rates in individuals 70 years or older. The prevalence of with-the-rule astigmatism was higher in individuals 40 years or younger, whereas rates of against-the-rule and oblique astigmatism increased with age. Astigmatic patients experienced decreased vision quality, increased glare (53 to 77%), haloes (28 to 80%), night-time driving difficulties (66%), falls, and spectacle dependence (45 to 85%). Astigmatic patients performed vision-related tasks slower (1 D, 9% slower; 2 D, 29% slower) and made more errors (1 D, 38% more errors; 2 D, 370% more errors) compared with fully corrected individuals. In cataract patients with astigmatism, the annual mean per-patient productivity loss costs ranged from €55 ($71) to €84 ($108), and mean informal care costs ranged from €30 ($39) to €55 ($71) with a mean of 2.3 to 4.1 hours spent on informal care.

CONCLUSIONS

Uncorrected astigmatism decreases patients' vision-related quality of life, decreases productivity among working-age adults, and poses an economic burden on patients and their families.

Exploration of the Visual Function after the Implantation of Continuous Visual Range Human Cocrystal Micromonocular Vision in Both Eyes of the Patient

Eye diseases such as myopia, hyperopia, astigmatism, and cataract are have affected most people at home and abroad for many years. With the development of science and technology, people who wear glasses are now younger, and they are on the rise over time. This paper is to explore the visual function after the implantation of continuous visual range human cocrystal micromonocular vision in both eyes of the patient. On this basis, the latest visual sensor technology is used to conduct clinical research on the operation, a case-control study is performed on the patient's eyes, followed by intraocular lens insertion surgery, one eye is hemitrope and the other eye has a certain degree of intraocular lens inserted, and it is recorded within a period of time after the operation. According to the analysis of the experimental results, the patient's naked eye and corrected distance vision is (t = 2.102, P = 0.049), middle distance vision (t = 1.403, P = 0.200), and near vision (t = 1.463, P = 0.216). After the operation, the ratio of patients taking off glasses 91.8%. After the continuous visual range intraocular lens micromonocular vision design, it can well correct the patient's near and far vision of the naked eye of both eyes.

In Vitro Chromatic Performance of Three Presbyopia-Correcting Intraocular Lenses with Different Optical Designs

Most of the new premium models of intraocular lenses for presbyopia correction use diffractive optics in their optical design. The presence of multiple foci and the difference of the diffractive efficiency for different wavelengths have a great impact in the lens optical performance. In this context, there is a limited information available for clinicians to understand the optical principles that differentiate each design and their potential influence on clinical outcomes. Optical bench studies with polychromatic light are necessary to solve this limitation. In this work, a custom made optical bench was employed to assess with polychromatic light the through the focus optical quality of three different IOL designs: trifocal, EDOF effect; and enhanced monofocal. By using different and complimentary approaches: images of the USAF test, axial PSFs and TF-MTFs, each design revealed its intrinsic features, which were not previously reported for these IOLs models in a comparative way. It was found that the chromatic aberration plays a very important role in the performance of each IOL. Our results could help clinicians to understand the optical principle of each lens and also provide useful information for choosing the lens that best suits the needs of the individual patient.

Comparative Efficacy Between Trifocal and Bifocal Intraocular Lens Among Patients Undergoing Cataract Surgery: A Systematic Review and Meta-Analysis

The comparative efficacy of trifocal and bifocal intraocular lenses (IOLs) remained uncertain among patients undergoing cataract surgery. A systematic review and meta-analysis was performed to answer this question. PubMed, Cochrane Library and Embase were searched to capture relevant randomized controlled trials (RCTs). Visual acuity (VA) and patient's satisfaction were regarded as primary outcomes. Secondary outcomes included residual sphere, spherical equivalence, residual cylinder, posterior capsular opacification (PCO), spectacle independence, and other complications. Statistical analysis was done using RevMan 5.2.0. A total of 9 studies (11 RCTs) with 297 participants (558 eyes) were included. Meta-analysis showed significant differences between trifocal and bifocal IOLs in the uncorrected near VA (mean difference [MD], −0.008; 95% confidence interval [Cl], −0.015 to −0.001; P = 0.028) and uncorrected intermediate VA (MD, −0.06; 95% CI, −0.10 to −0.02; P < 0.01). Trifocal IOLs were associated with decreased PCO incidence when compared to bifocal IOLs (relative risk [RR], 0.54; 95% CI, 0.31 to 0.95; P = 0.03). Trifocal IOLs may be superior to bifocal IOLs because of its improved intermediate VA and reduced incidence of PCO.

Measures of visual disturbance in patients receiving extended depth-of-focus or trifocal intraocular lenses

The degree of visual disturbance associated with a particular model of intraocular lens (IOL) depends on several factors, including IOL optic, material, and mechanics. Characterization of visual disturbance profiles is paramount for informing clinical IOL selection. Although many studies evaluating presbyopia-correcting IOLs include subjective assessment of visual symptoms, the types of patient-reported outcome measures (PROMs) used to capture these outcomes are inconsistent across studies, complicating data contextualization. Furthermore, some tools produce more meaningful results than others. This review presents a discussion on the scientific literature published on the subjective and semiobjective (halo and glare simulator, light-distortion analyzer, vision monitor, and halometers) methods used to assess visual disturbances in patients implanted with trifocal or extended depth-of-focus IOLs, highlighting their advantages and limitations. It underscores the importance of between-study comparisons and the need for standardized PROMs in clinical IOL research to provide more accurate information for IOL selection.

Comparison of Visual Performance and Patient Satisfaction Outcomes with Two Trifocal IOLs with Similar Optical Design but Different Materials

Purpose

To compare clinical outcomes in a prospective trial of cataract surgery patients bilaterally implanted with two different trifocal intraocular lenses (IOLs) with very similar optical designs but consisting of different IOL materials (hydrophobic and hydrophilic).

Patients and Methods

Fifty-one patients (102 eyes) were randomized to receive trifocal IOLs bilaterally – FineVision POD F (hydrophilic) or FineVision POD F GF (hydrophobic) (both PhysIOL, Liége, Belgium). The follow-up period was 3 months. Outcome measurements included uncorrected distance (UDVA), corrected distance (CDVA), distance-corrected intermediate (DCIVA), and distance-corrected near visual acuity (DCNVA), refraction, negative dysphotopsia, optical quality of vision, contrast sensitivity under photopic and mesopic conditions, halometry (discrimination index), and patient-reported outcomes.

Results

At the final study visit, mean (SD) values for binocular UDVA, CDVA, DCIVA (80 cm), and DCNVA (40 cm) were −0.01 (0.06), −0.04 (0.04), 0.09 (0.10), and 0.10 (0.09) logMAR, respectively, for POD F, and 0.01 (0.08), −0.03 (0.03), 0.08 (0.1), and 0.13 (0.11) respectively, for POD F GF. Defocus assessments showed a continuous curve with a functional range of visual acuity (≤0.15 logMAR) from ~30 cm to infinity in both groups. The discrimination index was >0.85 for all patients, and both groups showed similar contrast sensitivity under photopic and mesopic conditions. At 3 months, no patient reported negative dysphotopsia, and high satisfaction rates were observed.

Conclusion

Clinical outcomes showed no significant difference between each lens when measured at 1 month and 3 months after implantation. This equally good clinical performance of hydrophilic and hydrophobic trifocal lenses allows the surgeon to choose the IOL material based on personal preferences or patients’ needs.

Comparison of visual and refractive outcomes between hydrophilic and hydrophobic trifocal intraocular lenses sharing the same optical design

PURPOSE

To compare clinical outcomes between two trifocal intraocular lenses (IOLs): the new FineVision POD F GF trifocal IOL made of hydrophobic acrylic glistening-free material, and the FineVision POD F IOL made of hydrophilic acrylic material with 26% water uptake in patients undergoing routine cataract surgery using standard phacoemulsification.

SETTING

Semmelweis University, Department of Ophthalmology, Budapest, Hungary.

DESIGN

Prospective controlled randomized single-center single-surgeon study.

METHODS

Each patient had the hydrophilic POD F IOL implanted in one eye and the hydrophobic POD F GF IOL in the contralateral eye, according to a randomization table. Clinical outcomes included distance (4 m), intermediate (70 cm), and near (35 cm) visual acuities, contrast sensitivity measured under photopic and mesopic conditions, and defocus curves under photopic conditions. The follow-up was 6 months.

RESULTS

The study comprised 25 patients. Under photopic conditions, there was no statistically significant difference between POD F GF and POD F IOLs for uncorrected distance (UDVA) (P = .607), uncorrected intermediate (UIVA) (P = .491), and uncorrected near (UNVA) (P = .414) visual acuities. Under mesopic conditions, there was no statistically significant differences between the 2 IOLs for UDVA (P = 1.00), UIVA (P = .149), and UNVA (P = .551). No statistically significant differences in contrast sensitivity were found between the groups under photopic (P = .4347) and mesopic (P = .425) conditions. No safety issues were reported.

CONCLUSION

The study demonstrated equally good visual and refractive outcomes for the POD F GF IOL and the POD F IOL, giving the surgeon the option to choose the preferred material for the individual patient without compromising clinical outcomes.

Biomechanical Stability of Three Intraocular Lenses With Different Haptic Designs: In Silico and In Vivo Evaluation

PURPOSE

To assess the biomechanical stability of three different marketed intraocular lenses (IOLs) with different haptic designs (four-loop IOL [Micro F FineVision model] and double C-loop IOL [POD F and POD FT models], all manufactured by PhysIOL), in silico (computer simulation) and in vivo (in the context of lens surgery).

METHODS

An in silico simulation investigation was performed using finite element modeling (FEM) software to reproduce the compression test defined by the International Organization for Standardization and in vivo implantation in patients in the context of lens surgery was evaluated 1 day and 3 months postoperatively. IOL decentration and rotation were tested. In addition, the stress and strains were analyzed with the finite element method.

RESULTS

In the in silico evaluation, the compression force for the POD F IOL was slightly lower than for the POD FT IOL and Micro F IOL for all compression diameters. The axial displacement was maximum for the POD FT IOL and the tilt, rotation, and lateral decentration were substantially lower than the acceptable tolerance limits established in ISO 11979-2. In the in vivo evaluation, a total of 45 eyes from 45 patients were selected, 15 eyes for each IOL model under assessment. Statistically significant differences were found between the Micro F and POD F IOLs for lateral decentration in x-direction (in absolute value) at 3 months postoperatively (P = .03).

CONCLUSIONS

Although statistically significant differences have been found when comparing the displacement, tilt, and rotation between the different lenses, these differences cannot be considered clinically relevant, which would suggest that all three IOL models yield excellent stability in those terms. FEM appears to be a powerful tool for numerical studies of the biomechanical properties of IOLs. [J Refract Surg. 2020;36(9):617-624.].

Evaluation of the optical performance for aspheric intraocular lenses in relation with tilt and decenter errors

PURPOSE

To evaluate and compare the effect of misalignment and tilt on the optical performance of different aspheric intraocular lens (IOL) designs.

METHODS

Three aspheric IOLs with a different quantity of spherical aberration (SA) have been designed and the effect of IOL misalignment and tilt on the imaging quality of an eye model has been numerically assessed using a commercial optical design software. The prototypes have been manufactured by lathe turning and tested in vitro using the same optical bench (PMTF, Lambda-X) that complies with International Organization for Standardization standard 11979-2 requirements. Image quality was evaluated from the modulation transfer functions (MTFs), through-focus modulation transfer functions (TF-MTFs), root mean square (RMS) values of defocus, astigmatism and coma, and images of the United States Air Force (USAF) target were taken. A comparison with the optical performance of spherical IOLs has also been performed.

RESULTS

Intraocular lens misalignment and tilt increased wavefront aberrations; the effect of misalignment on root mean square (RMS) astigmatism and coma was positively correlated with the spherical aberration of the IOL. Aberration-free IOLs showed the highest MTF for all misalignment values and for IOLs with negative SA correction the MTF decays below 0.43 when they are decentered 0.50 mm.

CONCLUSIONS

Aspherical IOLs are more sensitive than spherical IOLs to misalignment or tilt, depending on their SA correction. The optical degradation caused by IOL misalignment had a greater effect on IOL designs with a higher amount of negative spherical aberration. In contrast, the effect of tilt on the optical performance was less sensitive to the IOL design.

Pre-operative simulation of post-operative multifocal vision

While multifocal intraocular lenses (MIOLs) are increasingly implanted to correct for presbyopia, how one sees with a multifocal correction is hard to explain and imagine. The current study evaluates the quality of various visual simulating technologies by comparing vision with simulated MIOLs pre-operatively and the implanted MIOLs post-operatively in the same patients. Two simulation platforms were used: (1) a custom-developed adaptiveoptics (AO) system, with two visual simulator devices: a spatial light modulator (SLM) and an optotunable lens operating under temporal multiplexing (SimVis); and (2) a wearable, binocular, large field of view SimVis2Eyes clinical simulator (SimVis Gekko, 2Eyes Vision, Madrid, Spain). All devices were programmed to simulate a trifocal diffractive MIOL (POD F, FineVision, PhysIOL). Eight patients were measured pre-operatively simulating the trifocal lens and post-operatively with implantation of the same MIOL. Through-focus decimal visual acuity (TF VA) was measured (1) monocularly in monochromatic light using a four-alternative-forced-choice procedure in the AO system; and (2) binocularly using a clinical optotype in white light. Visual simulations pre-operatively predict well the TF VA performance found post-operatively in patients implanted with the real IOL. The average RMS difference between TF curves with the different visual simulators was 0.05 ± 0.01. The average RMS difference between the TF VA curves with the SimVis pre-operatively and the real MIOL post-operatively was 0.06 ± 0.01 in both platforms, and it was higher in cataract eyes (0.08 ± 0.01, on average across simulators) than in eyes with clear lens. In either group the shape of the TF curves is similar across simulators and pre- and post-operatively. TF curves cross-correlated significantly between simulators (lag k = 0, rho = 0.889), as well as with results with the real MIOL implanted (lag k = 0, rho = 0.853). Visual simulations are useful programmable tools to predict visual performance with MIOLs, both in an AO environment and in a clinical simulator. Pre-operative visual simulations and post-operative data are in good agreement.

Visual Function after Implantation of a Presbyopia-Correcting Trifocal Intraocular Lens

PURPOSE

To evaluate distance, intermediate, and near visual performance in patients implanted with a trifocal aspheric presbyopia-correcting intraocular lens (IOL).

METHODS

Forty patients were bilaterally implanted with the AcrySofIQ PanOptix IOL after femtosecond laser-assisted lens surgery. Binocular best corrected distance visual acuity (CDVA) (4 m), best distance-corrected near visual acuity (DCNVA) (40 and 30 cm), best corrected distance intermediate visual acuity (DCIVA) (70, 60, and 50 cm), binocular distance contrast sensitivity under photopic conditions (85 cd/m2), and defocus curves were evaluated at 6-months.

RESULTS

Six months postoperatively, the mean binocular Snellen decimal CDVA and DCNVA were 0.94 ± 0.10 (ranging from 0.70 to 1.25) and 0.85 ± 0.13 (ranging from 0.63 to 1.00), respectively. At a distance, all patients showed a cumulative binocular distance-corrected visual acuity of 0.8 or better, and about 80% (n = 31) of the patients had a value of 1.0 (20/20). At near and intermediate distances, all patients showed a cumulative distance-corrected visual acuity of 0.5 (20/40) or better at 30, 40, 50, 60, and 70 cm. Specifically, 50 cm showed the highest percentage of patients with larger values of visual acuity (60% [n = 26] with 20/20). Defocus curve showed a wide range of useful vision with two peaks of best visual acuity at distance and at 50 cm, and the binocular distance contrast sensitivity was within normal limits.

CONCLUSIONS

The outcomes of the present study show that the visual performance obtained with bilateral implantation of the trifocal aspheric AcrySofIQ PanOptix IOL is good at far, intermediate, and near distances.

Stability and visual outcomes yielded by three intraocular trifocal lenses with same optical zone design but differing material or toricity

PURPOSE

To compare rotational stability, centration and visual outcomes provided by three trifocal lens models that have the same optical zone design but different material, composition, and/or toricity.

METHODS

The study included 78 patients with symmetric bilateral intraocular lens implantation. The lenses under evaluation were trifocal intraocular lenses made of hydrophilic acrylic material: a spherical lens 26% hydrophilic acrylic (POD FineVision), a similar lens but having a toric design (POD Toric FineVision), and a trifocal lens 25% hydrophilic acrylic material (FineVision/MicroF). Moreover, the lenses share the same optical zone design. The lenses' rotational stability and centration were measured by means of the PIOLET software, which relies on recording and image processing techniques to determine lens rotation and centration based on slit-lamp images. We also assessed patients' visual quality by means of 25, 40, and 80 cm VA tests.

RESULTS

The best centration results were achieved with the POD Toric FineVision model, although the differences were not statistically significant. As for lens rotation, it was below 5° in all cases under study. Regarding VA, all subjects attained at least 0.3 logMAR for far distance uncorrected VA, at 80 cm VA was about 0.2 logMAR, at 40 cm it was above 0.15 logMAR, and at 25 cm it was about 0.3 logMAR for both lens types.

CONCLUSION

All three intraocular lens models yield excellent visual results at far, near as well as intermediate distances. The POD FineVision and POD Toric FineVision models, with double C-loop design, yielded the best results centration-wise and rotation-wise. Differences had no clinical relevance.

Visual Performance With Bifocal and Trifocal Diffractive Intraocular Lenses: A Prospective Three-Armed Randomized Multicenter Clinical Trial

PURPOSE

To evaluate and compare quality of vision and reading performance outcomes after implantation of bifocal refractive-diffractive, bifocal apodized diffractive, or trifocal diffractive-refractive intraocular lenses (IOLs).

METHODS

This randomized, prospective, three-armed multicenter (Spain, Germany, and France) trial included 104 eyes of 52 patients (mean age: 63.2 ± 7.7 years). Patients underwent cataract surgery with bilateral implantation of either AT LISA 809M (Carl Zeiss Meditec, Jena, Germany: AT LISA group, 38 eyes), AT LISA tri 839MP (Carl Zeiss Meditec: AT LISA tri group, 32 eyes), or ReSTOR SN6AD1 (Alcon Laboratories, Inc., Fort Worth, TX: ReSTOR group, 34 eyes) IOLs. Visual and refractive outcomes, depth of focus, and reading performance were evaluated at 1, 6, and 12 months postoperatively.

RESULTS

The AT LISA tri group showed significantly better 12-month uncorrected (UIVA) and binocular distance-corrected (DCIVA) intermediate visual acuity (P ≤ .016) than the AT LISA group. The AT LISA tri group showed a significantly better 3-month UIVA compared to the ReSTOR group (P = .042). Binocular uncorrected and corrected distance visual acuities were not significantly different among groups (P ≥ .092) at the 12-month follow-up. A total of 85.3%, 90.0%, and 78.1% of eyes had a spherical equivalent within ±0.50 D in the AT LISA, AT LISA tri, and ReSTOR groups, respectively, at 12 months (P = .038). No statistically significant differences between the trifocal and bifocal groups were detected for reading performance (P ≥ .055).

CONCLUSIONS

The trifocal diffractive-refractive IOL provides enhanced intermediate visual restoration compared to bifocal diffractive-refractive or apodized diffractive IOLs. The addition of an intermediate focal point did not deteriorate far or near vision. A comparable reading performance was maintained with the trifocal lens. [J Refract Surg. 2017;33(10):655-662.].

Myopic Shift after Implantation of a Novel Diffractive Trifocal Intraocular Lens in Korean Eyes

Purpose

To evaluate the clinical outcomes of cataract surgery using novel diffractive trifocal intraocular lenses (IOLs) in Koreans.

Methods

This was a retrospective, consecutive, interventional study of cataract surgery using POD FineVision IOL implantation. Complete ophthalmologic examinations were performed preoperatively and postoperatively. Defocus curves were assessed over a range of +1.5 to −4.0 diopters in 0.5-diopter steps at one month postoperatively. Uncorrected distant visual acuity, uncorrected intermediate visual acuity, uncorrected near visual acuity, corrected distant visual acuity, distant-corrected intermediate visual acuity, and distant-corrected near visual acuity were assessed one month postoperatively, and manifest refraction was performed during every visit.

Results

The study analyzed 31 eyes in 20 patients. There were statistically significant improvements in uncorrected distance visual acuity, uncorrected intermediate visual acuity, uncorrected near visual acuity, corrected distance visual acuity, distance-corrected intermediate visual acuity, and distance-corrected near visual acuity (p < 0.001). The final postoperative refractive outcomes showed statistically significant myopic shifts compared to the target refraction based on SRK/T, SRK-II, Haigis, and Hoffer Q formulas (p < 0.001).

Conclusions

POD FineVision IOLs provide stable visual restoration with improvements of near and intermediate vision in presbyopic eyes. POD FineVision IOLs show myopic shift in a Korean population; therefore, surgeons should be cautious when selecting IOL power in such patients.

Comparison of clinical performance between trifocal and bifocal intraocular lenses: A meta-analysis

PURPOSE

To compare the clinical performance between trifocal and bifocal intraocular lenses in bilateral cataract and/or refractive lens exchange (RLE) surgery.

METHODS

A comprehensive literature search of PubMed, EMBASE, Cochrane Controlled Trials Register and Web of Science was performed through October 2016 to identify randomized, controlled trials (RCTs) and comparative cohort studies. The primary outcomes were uncorrected distance visual acuity (UDVA), uncorrected intermediate visual acuity (UIVA), uncorrected near visual acuity (UNVA), defocus curve, spectacle independence, patient satisfaction and contrast sensitivity. The secondary outcomes were residual sphere, spherical equivalent (SE), cylinder and complications.

RESULTS

Six RCTs and 2 cohort studies including 568 eyes (278 in the trifocal group and 290 in the bifocal group) were identified. There was a statically significant difference between the two groups in UDVA (WMD: -0.03, 95% CI: -0.05 to -0.01, P = 0.005), but the difference (0.03 log MAR) is not clinically significant. Intermediate visual acuity was better in the trifocal IOL group judging from UIVA and defocus curves. There was a statically significant difference between the two groups in residual cylinder (WMD: 0.11, 95% CI: 0.02 to 0.20, P = 0.02), and subgroup AT Lisa tri 839MP trifocal also showed significant better UNVA than bifocal IOLs (WMD: -0.13, 95% CI: -0.17 to -0.08, P<0.00001). However, no significant differences were observed in UNVA (WMD: -0.04, 95% CI: -0.11 to 0.02, P = 0.19), spectacle independence (WMD: 1.27, 95% CI: 0.89 to 18.15, P = 0.07), patient satisfaction (WMD: 4.01, 95% CI: 0.07 to 22.72, P = 0.87), residual sphere (WMD: -0.03, 95% CI: -0.18 to 0.13, P = 0.74), SE (WMD: 0.04, 95% CI: -0.09 to 0.16, P = 0.55) or complications (WMD: 2.08, 95% CI: 0.35 to 12.43, P = 0.42).

CONCLUSIONS

Trifocal IOL technology (especially AT Lisa trifocal 839M trifocal) had a clear advantage over bifocal IOLs in intermediate visual acuity, while both trifocal IOLs and bifocal IOLs showed excellent performance in distance visual acuity. AT Lisa trifocal 839M trifocal could provide better uncorrected near visual acuity than bifocal IOLs. However, more evidence is needed to compare their spectacle independence, higher satisfaction rate, and photic phenomena.

Objective and subjective results following implantation of the FineVision trifocal intraocular lens in Mexican patients

PURPOSE

To evaluate objective and subjective results after bilateral implantation of a diffractive trifocal intraocular lens (IOL) in a Mexican population.

METHODS

Prospective, interventional case series involved 15 cataract surgery patients who underwent bilateral implantation of the trifocal Micro F lens FineVision IOL (PhysIOL, Liège, Belgium). Objective analysis involved assessment of monocular uncorrected distance (UDVA), near (UNVA) at 30 and 40 cm, and intermediate visual acuity (UIVA) at 50, 60, and 70 cm, preoperatively, and at postoperative months 1, 3, and 6. Higher-order aberrations were assessed via aberrometry. Contrast sensitivity was determined via modulation transfer function. Subjective outcomes were assessed using the National Eye Institute Visual Functioning Questionnaire-25 (VFQ-25).

RESULTS

At postoperative month 6, mean monocular UDVA was 0.06 ± 0.11 logMAR, and UNVA was 0.03 ± 0.04 logMAR at 30 cm and 0.05 ± 0.08 logMAR at 40 cm. Mean UIVA at 50, 60, and 70 cm was 0.12 ± 0.06, 0.13 ± 0.08, and 0.04 ± 0.08 logMAR, respectively. Spherical equivalent at postoperative month 3 was 0.23 ± 0.4 diopters (D). Aberrometry revealed a mean RMS of 0.18 microm and PSF of 0.19 (Strehl ratio). VFQ-25 questionnaire results showed a mean score of 93.64 ± 4.19 points (maximum 100 points). Vision during distance and near activities was reported as "excellent." Adverse events were reported as occurring "never to occasionally."

CONCLUSION

Implantation of a diffractive trifocal IOL in a Mexican population appears safe and effective, both objectively and subjectively. Good uncorrected visual acuity outcomes were achieved at far, near, and intermediate distances. Overall patient satisfaction was excellent.

Trifocal intraocular lenses: a comparison of the visual performance and quality of vision provided by two different lens designs

Purpose

To compare two different diffractive trifocal intraocular lens (IOL) designs, evaluating longer-term refractive outcomes, visual acuity (VA) at various distances, low contrast VA and quality of vision.

Patients and methods

Patients with binocularly implanted trifocal IOLs of two different designs (FineVision [FV] and Panoptix [PX]) were evaluated 6 months to 2 years after surgery. Best distance-corrected and uncorrected VA were tested at distance (4 m), intermediate (80 and 60 cm) and near (40 cm). A binocular defocus curve was collected with the subject’s best distance correction in place. The preferred reading distance was determined along with the VA at that distance. Low contrast VA at distance was also measured. Quality of vision was measured with the National Eye Institute Visual Function Questionnaire near subset and the Quality of Vision questionnaire.

Results

Thirty subjects in each group were successfully recruited. The binocular defocus curves differed only at vergences of −1.0 D (FV better, P=0.02), −1.5 and −2.00 D (PX better, P<0.01 for both). Best distance-corrected and uncorrected binocular vision were significantly better for the PX lens at 60 cm (P<0.01) with no significant differences at other distances. The preferred reading distance was between 42 and 43 cm for both lenses, with the VA at the preferred reading distance slightly better with the PX lens (P=0.04). There were no statistically significant differences by lens for low contrast VA (P=0.1) or for quality of vision measures (P>0.3).

Conclusion

Both trifocal lenses provided excellent distance, intermediate and near vision, but several measures indicated that the PX lens provided better intermediate vision at 60 cm. This may be important to users of tablets and other handheld devices. Quality of vision appeared similar between the two lens designs.