Types Of Multifocal Intraocular Lenses Research Articles

Correlation of angle kappa and angle alpha on visual outcomes in eyes implanted with three types of multifocal intraocular lenses.

To evaluate the correlation between preoperative, postoperative, and change in angle kappa and alpha to visual outcomes following implantation of three multifocal intraocular lenses. This is a retrospective study which included 122 eyes of 61 patients. There were 38 eyes in the Synergy (Johnson & Johnson, USA) group and 42 eyes each from both the Panoptix (Alcon Laboratories, USA) and FineVision (Physiol BVI, Belgium) groups. Visual outcome parameters (uncorrected distance, intermediate, near vision, halo and starburst) and angle kappa and alpha were recorded preoperatively and at three months postoperatively. The preoperative, postoperative and the amount of change in angle kappa and alpha were correlated to visual outcomes and photic phenomena among the three different diffractive trifocal IOLs. There were no significant differences in the preoperative and postoperative magnitude of angle kappa and alpha among the Synergy, Panoptix, and FineVision groups. There was no significant correlation between the preoperative and postoperative magnitude, and change in angle kappa and alpha with the postoperative uncorrected distance, intermediate and near visual acuity, and halo and starburst scores of the three different diffractive IOLs. The frequency of eyes with greater than 0.5mm angle kappa and alpha values were low. Visual outcomes can be good even in eyes in which the angle kappa and alpha were greater than 0.5mm. The newer diffractive multifocal IOLs were observed to be more tolerant to low and intermediate levels of angle kappa and alpha.

Stereopsis Following Implantation of Presbyopia-Correcting Intraocular Lenses: A Narrative Review.

Recent advancements in cataract surgery have broadened its scope from mere vision restoration to include correction of refractive errors and presbyopia. This evolution has introduced multifocal and extended depth-of-focus (EDOF) intraocular lenses (IOLs), allowing enhanced vision across multiple distances. However, the influence of these advanced IOLs on stereopsis remains controversial. Factors influencing stereopsis after surgery include visual acuity, interocular differences, residual astigmatism, and the type of IOL, etc. Binocular vision integration and neuroadaptation further affect stereopsis, especially in cases of presbyopia-correcting IOLs. It is widely acknowledged that bilateral implantation of presbyopia-correcting IOLs yield superior stereopsis compared to unilateral implantation. However, there remains no consensus on whether binocular implantation of multifocal or monofocal IOLs provides superior stereopsis. Most studies suggest no significant difference in stereopsis between these two types of implants. Among different types of multifocal IOLs, refractive multifocal IOLs may offer better stereopsis than diffractive multifocal IOLs when implanted bilaterally. Emerging EDOF and hybrid multifocal-EDOF IOLs also demonstrate promising postoperative stereopsis. Additionally, a mix-and-match strategy with different types of IOLs implanted in each eye may result in interocular differences in visual acuity at certain distances, potentially affecting stereopsis. Nevertheless, with appropriate selection, most patients can achieve satisfactory postoperative stereopsis. This review synthesizes current literature on the effects of presbyopia-correcting IOLs on postoperative stereopsis recovery following cataract surgery. Studies on stereopsis outcomes with different IOLs have yielded mixed results, urging further investigation for optimized surgical strategies and patient outcomes.

Comparative Analysis of Tolerance to Experimentally Induced Astigmatism with Three Types of Multifocal Intraocular Lenses.

The effect of residual astigmatism and its axis on distance and near visual acuities (VAs) with multifocal intraocular lenses (IOLs) has not been studied extensively. This study compared the tolerance to experimentally induced residual astigmatism among bifocal, trifocal, and extended depth-of-focus (EDOF) IOLs. This retrospective, comparative study included 70 eyes of 70 patients implanted with bifocal, trifocal, or EDOF IOLs. Distance and near VAs were assessed with experimentally induced astigmatism by placing positive cylindrical lenses in increments of 0.50 diopters to 2.00 diopters at 90° and 180° axes over the best distance correction. Both distance and near VAs worsened with increasing magnitudes of experimentally induced astigmatism except in the EDOF group, in which the near VA remained within a clinically acceptable limit, ie, within one line from the best corrected VA under all ranges of experimentally induced astigmatism. Furthermore, the EDOF group showed the highest astigmatic threshold for losing VA lines following experimental astigmatic induction at both distance and near. The distance VA was generally better at with-the-rule (WTR) than against-the-rule (ATR) astigmatism for all three IOL groups. On the other hand, the near VA was generally better at WTR than ATR astigmatism in the bifocal group, comparable between WTR and ATR astigmatism in the trifocal group, and generally better at ATR than WTR astigmatism in the EDOF group. The EDOF IOL demonstrated the highest tolerance to experimentally induced astigmatism at both distance and near. VA was generally less affected by WTR astigmatism than ATR astigmatism, especially at distance. We proposed the residual astigmatism thresholds for clinically acceptable VA reduction in all three IOL groups.

Preoperative Biometry and Effective Adding Power of the Multifocal Intraocular Lens

Purpose: To calculate the length of near focus or effective adding power on the corneal plane after implantation of a diffractive multifocal intraocular lens (IOL).Methods: The study was designed as theoretical study. After eye models with corneal powers ranging from 36 to 48 diopter (with intervals of 2 diopter) and axial lengths ranging from 20 to 30 mm (with intervals of 2 mm) were simulated to calculate IOL power for an emmetropic target, the adding power of a multifocal IOL was added to the IOL power and the near target diopter was calculated from the total IOL power. The simulation was performed using three types of multifocal IOLs: the AMO TECNIS ZMB00, ZLB00, and ZKB00 (+4.00 diopter, +3.25 diopter, and +2.75 diopter of adding powers at the IOL plane).Results: As the preoperative corneal power or axial length increased, the effective adding power decreased. When the shape of the cornea was abnormally steep, the effective adding power was lowest when the SRK/T formula was used, followed in ascending order by the Holladay 1 and Hoffer Q formulas. As the cornea became flatter, the effective adding power was the lowest when the Hoffer Q formula was used, followed by the Holladay 1 and SRK/T formulas.Conclusions: The effective adding power and focal length on the near target changes according to preoperative biometry and the formula used for theoretical IOL calculation.

Nd:YAG Capsulotomy Rates with Two Multifocal Intraocular Lenses.

PurposeTo investigate the incidence of Nd:YAG capsulotomy after implantation of two types of multifocal intraocular lenses (MIOLs).MethodsThis retrospective analysis included patients who had undergone cataract extraction and implanted diffractive MIOL (Acri. LISA tri 839M) or asymmetric refractive MIOL (SBL-3) from May 2016 to September 2018. They were followed up for at least 3 years. During the follow-up period, the relevant data of patients were kept by special person in the hospital. The rates of Nd:YAG capsulotomy and the Kaplan–Meier survival curve were used to analyze the two groups.ResultsThe Asymmetric Refractive MIOL group was comprised of 98 patients (121 eyes), while the Diffractive MIOL group was comprised of 99 patients (120 eyes). There were no significant differences in age, sex, or IOL power between the two groups. The Nd:YAG rate of the asymmetric refractive MIOL group and the diffractive MIOL group was 3.3% and 7.5% respectively (P = 0.15) in the first year, 14.88% and 22.5% respectively (P = 0.129) in the second year, and 21.49% and 34.17% respectively (P = 0.028) in the third year. In the first 7 months of follow-up, the two groups showed the same performance in the Nd:YAG rate. After that, there was a difference between the two groups, and the difference gradually increased. Until the 27th month of follow-up, the difference was significant (P < 0.05). What is more, there were significant differences in survival (without Nd:YAG capsulotomy)/failure (with Nd:YAG capsulotomy) functions (P = 0.0035).ConclusionThe incidence of Nd:YAG laser capsulotomy in patients with diffractive MIOLs was higher than that in patients with asymmetric refractive MIOLs.

Citation network analysis of the various types of multifocal intraocular lenses.

The implantation of multifocal intraocular lens (IOL) has increased in recent years, allowing patients to achieve good quality vision at all distances, independence from use of glasses, and consequently, an increase in quality of life. The main purpose of this study was to analyse the links between publications and authors via citation networks, as well to as identify the different research areas and determine the most cited publications. The publication search was performed through the Web of Science database, using the terms «Multifocal intraocular lens», «Bifocal intraocular lens», «Trifocal intraocular lens», «Diffractive intraocular lens», «Refractive intraocular lens», «Accommodative intraocular lens» and «Extended depth of focus intraocular lens», for a time interval from 1989 to August 2020. The software used to analyse the publications was the Citation Network Explorer. A total of 1293 publications were found, with 11,730 citations generated in the network, and 2019 had the highest number of publications of any year. The most cited publication was «European multicenter study of the AcrySof ReSTOR apodized diffractive intraocular lens» by Kohnen et al., published in 2006. Four groups about different research areas in this field were found using the Clustering functionality: visual quality, IOL designs, ocular aberrations, or defocus curves. The citation network offers an objective and comprehensive analysis of the main articles on the different designs and classes of multifocal IOL.

The Effect of Age, Postoperative Refraction, and Pre- and Postoperative Pupil Size on Halo Size and Intensity in Eyes Implanted with a Trifocal or Extended Depth-of-Focus Lens.

PurposeHalos are a chief source of patient dissatisfaction after multifocal intraocular lens (IOL) implantation. The primary purpose of this study was to investigate the influence of age, postoperative refraction, and pre- and postoperative pupil size on postoperative halo size with a trifocal diffractive IOL (AcrySof IQ PanOptix) and extended depth-of-focus (EDOF) IOL (TECNIS Symfony) to determine whether these factors could predict postoperative halo size.Patients and MethodsThis single-center, open-label study conducted between October 2018 and April 2020 in Yokosuka, Japan included 160 patients: 80 with PanOptix and 80 with Symfony IOLs. Size and intensity of the halos were examined binocularly using a computer-based simulator (Eyeland Design Network GmbH) and scored from 0 (minimum) to 10 (maximum) at 1, 3, and 6 months postoperatively, along with the change in each variable for both IOLs. The respective correlations of halo size with age, postoperative refraction, pre- and postoperative pupil size, and discomfort level due to the halo were also investigated 6 months postoperatively.ResultsHalo size and intensity were significantly mitigated between 1, 3, and 6 months postoperatively. Throughout the observation period, halo size was significantly larger with PanOptix than with Symphony (P < 0.05), and halo intensity was significantly higher with Symphony than with PanOptix (P < 0.05). The pre- and postoperative pupil size correlated positively with halo size, while age and postoperative refraction were negatively correlated, for both IOLs.ConclusionUnderstanding the features and predictive preoperative factors of halos in different types of multifocal IOLs may be useful in improving patient satisfaction.

Comparing the visual outcome, visual quality, and satisfaction among three types of multi-focal intraocular lenses

This study compared the visual outcome, visual quality, and satisfaction following implantation of the Mix-and-Match bifocal IOLs (+ 2.75 D and + 3.25 D add power Tecnis Multifocal Model), EDOF IOL (Tecnis Symfony IOL), and Trifocal IOL (FineVision PodFT, PhysIOL). All outcomes were compared among the three groups. The manifest refraction indicated that the EDOF group had significantly higher myopic spherical equivalent values than did the others. In the terms of visual acuity, there were no significant differences in far or intermediate visual acuity among the three groups. Only in near (33 cm), the EDOF group had significantly worse binocular visual acuity than did the Trifocal group (p = 0.002). Regarding to defocus curve, the Trifocal group had better defocus curves at near distances (− 2.0 to − 3.5 D; p = 0.001 vs. EDOF) than did the other two groups. In contrast sensitivity test, the EDOF group had relatively lower value than did the other two groups. In reading speed, only at 0.3 logMAR (6.5-point font), Mix-and-Match group had a significantly higher reading speed than did the other two groups (p = < 0.001 vs. EDOF, p = 0.007 vs. Trifocal). also Mix-and-Match group showed significantly fewer visual artifacts. There were no differences between the three groups in terms of patient satisfaction.ClinicalTrials.gov number: NCT04019691.

Comparing the Visual Outcome, Visual Quality, and Satisfaction Among Three Types of Multi-focal Intraocular Lenses

Comparing the Visual Outcome, Visual Quality, and Satisfaction Among Three Types of Multi-focal Intraocular Lenses

Virtiol - Simulation of Quality of Vision with Multifocal and Edof Intraocular Lenses.

This was an experimental study involving atotal of 20 volunteers with artephakia (35 eyes). Each volunteer rated 5 types of IOLs, 4 presbyopia-correcting IOLs - WIOL-CF, Tecnis Symphony ZXR00, Acrysof IQ PanOptix TFNT00, M-flex 630 F, and as areference lens, we used the monofocal IOL Acrysof SA60AT. The corrected distance visual acuity (CDVA), distance corrected intermediated visual acuity (DCIVA) and distance corrected near visual acuity (DCNVA) were measured. Additionally, volunteers evaluated the quality of vision under normal or changed lighting conditions, and ranked IOL on scale from 1 to 5. The CDVA evaluated using the VirtIOL device was very good for all tested IOLs (0.04-0.09 log MAR) with minimum differences. However, CDVA without simulator (-0.01 logMAR) was statistically significantly better in all cases. DCIVA was also very similar in each of the investigated IOLs, surprisingly even with monofocal IOL (0.21-0.23 logMAR), without using simulator the DCIVA was statistically significantly worse (0.36 logMAR). The DCNVA was the best for PanOptix intraocular lens (0.22 logMAR); M-flex, Symphony and WIOL-CF lenses had comparable results (0.31-0.34 logMAR). Again, surprisingly similar results were obtained with the use of monofocal IOL (0.36 ± 0.14). Subjective perception of vision through the IOLs was best rated for the monofocal control IOL, whereas Symphony, WIOL-CF and M-flex did not show any statistically significant difference either with or without glare. All tested IOLs were statistically significantly better if compared to PanOptix with or without glare. Simulation of vision through IOLs using VirtIOL simulator allows to compare different models of multifocal IOLs from the viewpoint of visual acuity and subjective perception. However, some caution should be exercised when evaluating the results, given that in our experiments, the monofocal IOL achieved relatively good results at near distance, which does not correspond to clinical experience. On the contrary, from the comparison of the results of CDVA without and with VirtIOL, it is obvious that visual acuity is slightly adversely affected by added optics.

Progress in application of multifocal intraocular lens

New types of multifocal intraocular lens have launched nowadays, which can minimize the disadvantages, such as zonal refractive intraocular lens, extended range of vision intraocular lens, trifocal intraocular lens and so on. For the intermediate visual acuity and contrast sensitivity after cataract surgery, multifocal intraocular lens can improve greatly and minimize the disadvantages of glare and halos. This article summarizes the progress of new typies of multifocal intraocular lens on design and clinical application. Key words: Cataract; Lens, intraocular, multifocal, trifocal; Refractive, zonal; Vision, extended range

Comparison of long-term decentration and tilt in two types of multifocal intraocular lenses with OPD-Scan III aberrometer.

To compare the long-term decentration and tilt in two multifocal intraocular lenses (MfIOLs) with an OPD-Scan III aberrometer. Eighty cataract patients who underwent uneventful MfIOL implantation (42 with AcrySof® IQ ReSTOR® SN6AD1 and 38 with AMO Tecnis® ZMB00) were enrolled. At 1 year after surgery, a postoperative visual acuity evaluation included the measurement of uncorrected distance visual acuity, corrected distance visual acuity, distance-corrected near visual acuity, and distance-corrected intermediate visual acuity. OPD-Scan III aberrometer was used to collect the decentration, tilt, and high-order aberration (HOA) data. Significance was tested with Student's t test, Mann-Whitney U test, paired t test, and χ2 test RESULTS: The average intraocular tilt was lower in the SN6AD1 group than in the ZMB00 group, whereas the average decentration of the two groups did not differ significantly. The mean total ocular HOAs, ocular trefoil, total internal HOAs, and spherical aberrations were significantly lower in the SN6AD1 group than in the ZMB00 group. In both the SN6AD1 and ZMB00 groups, the intraocular tilt was directly proportional to the total ocular HOAs, coma, and spherical aberration. However, there was no significant correlation between decentration and any type of HOA in SN6AD1 group, whereas decentration correlated positively with total ocular HOAs, coma, and spherical aberration in ZMB00 group. Both MfIOLs significantly improve the visual acuity of the patients. However, tilt was lower in the SN6AD1 group than in the ZMB00 group 1 year after surgery, which provide fewer HOAs and better visual quality.

Residual Astigmatism Threshold and Patient Satisfaction with Bifocal, Trifocal and Extended Range of Vision Intraocular Lenses (IOLs)

Purpose: To compare the impact of induced astigmatism with four different types of multifocal intraocular lenses (MIOLs). Method: Prospective, comparative, interventional, mono-centered study, including 80 eyes of patients with implantation of four different MIOLs: AcrySof ReSTOR +2.5 D (20 eyes), AcrySof ReSTOR +3.0 D (20 eyes), AcrySof Panoptix (20 eyes) (Alcon Laboratories, Inc., Fort Worth, TX, USA), and Tecnis Symfony ZRX00 (Abbott Medical Optics, Santa Ana, USA) (20 eyes). Patients were followed up for 3 months after surgery. Major parameters were uncorrected (UDVA) and corrected (CDVA) distance visual acuity, subjective refraction and patient satisfaction. Results: Differences between IOLs with regard to the impact of the cylinder sign and axis on visual acuity and patient satisfaction were not significant. With mild added negative cylinder, AcrySof ReSTOR +2.5 D and Tecnis Symfony IOLs maintained the baseline visual acuity, while it was mildly reduced with AcrySof ReSTOR +3.0 D and Panoptix IOLs. With moderate induced cylinder, the Tecnis Symfony IOL maintained good visual acuity and patient associated satisfaction. Panoptix IOL was the IOL most affected by the induced astigmatism with regard to dissatisfaction and visual acuity. The highest tolerance to the astigmatic distortion and blurriness induced with a -1.50 D cylinder was obtained with the Tecnis Symfony IOL. Tecnis Symfony IOL showed less dissatisfaction and less reduction of visual acuity than the other MIOLs. Conclusion: Simulated residual cylinders after the implantation of the Tecnis Symfony IOL up to 1.0 D have a very mild and not clinically relevant impact on visual acuity or patient satisfaction. The ERV IOL showed a better tolerance to unexpected postoperative residual errors than diffractive bifocal and trifocal IOLs.

Optimizing outcomes with multifocal intraocular lenses.

Modern day cataract surgery is evolving from a visual restorative to a refractive procedure. The advent of multifocal intraocular lenses (MFIOLs) allows greater spectacle independence and increased quality of life postoperatively. Since the inception in 1980s, MFIOLs have undergone various technical advancements including trifocal and extended depth of vision implants more recently. A thorough preoperative workup including the patients’ visual needs and inherent ocular anatomy allows us to achieve superior outcomes. This review offers a comprehensive overview of the various types of MFIOLs and principles of optimizing outcomes through a comprehensive preoperative screening and management of postoperative complications.

Pseudolentogenic astigmatic effect of multifocal intraocular lenses: non-corneal ocular residual astigmatism (N-CORA) as a new parameter in astigmatic change analysis.

This study was initiated to introduce the term non-corneal ocular residual astigmatism (N-CORA) as a new parameter in astigmatic change analysis after implantation of two different types of non-toric, multifocal intraocular lenses (MIOL). Seventy-two eyes from 72 consecutive patients after MIOL surgery were studied in terms of a retrospective, cross-sectional data analysis. Two types of spherical MIOL were used. Surgical technique in all patients was a 2.4-mm incision phacoemulsification, performed by one surgeon. To investigate the magnitude and axis of astigmatic changes, the true corneal astigmatism and Alpins vector method were applied. There were no statistically significant between-group differences related to the preoperative refraction or ocular residual astigmatism (ORA). After surgery, the mean refractive surgically induced astigmatism (RSIA) and the topographic SIA (TSIA) did not differ significantly between the lenses. The magnitude and orientation of ORA and N-CORA changed after surgery. There are no statistically significant differences in postoperative ORA in magnitude or axis when implanting different types of MIOL. The similarity of N-CORA between both MIOL types shows that both diffractive and refractive asymmetric MIOLs with plate haptics have the same pseudolentogenic astigmatic effect which could be presented in terms of the newly introduced parameter N-CORA.

Clinical experience with the WIOL-CF accommodative bioanalogic intraocular lens: Czech national observational registry.

To assess efficacy and patient satisfaction after cataract surgery and implantation of a new accommodative bioanalogic intraocular lens (IOL). We evaluated the collected data of 48 patients with bilateral cataract surgery and Wichterle IOL (WIOL) implantation included in the Czech national observational registry. Monocular and binocular uncorrected distance visual acuity (UDVA), uncorrected intermediate visual acuity, uncorrected near visual acuity (UNVA), best spectacle-corrected visual acuity for distance (CDVA), best spectacle-corrected visual acuity for near (CNVA), distance-corrected near visual acuity (DCNVA), and distance-corrected intermediate visual acuity were evaluated 6 months after surgery. Subjective patient satisfaction was assessed at 3 months postoperatively. The mean monocular UDVA was 0.074 ± 0.108 logMAR, the mean monocular CDVA was 0.047 ± 0.125 logMAR, the mean monocular UNVA was 0.328 ± 0.146 logMAR, the mean monocular DCNVA was 0.339 ± 0.131 logMAR, and the mean monocular CNVA was 0.139 ± 0.107 logMAR. A total of 24 patients (50%) had no problems with any light phenomena. A total of 18 patients were very satisfied (37.5%), 11 were satisfied (22.9%), 15 (31.2%) were rather satisfied, 4 (8.3%) were rather dissatisfied, and 0 were dissatisfied. The WIOL-continuous focus polyfocal lens offers very good vision at far and intermediate distance comparable with other types of multifocal IOLs, and relatively good near vision, while the incidence of adverse side phenomena is relatively low.

Analyzing the reasons for patients’ dissatisfaction with the results of multifocal intraocular lens implantation

Aim. To analyze the causes for patients’ dissatisfaction with the results of multifocal intraocular lens implantation. Methods. The research is based on the results of cataract surgeries in 220 patients (50 patients were implanted multifocal refractive intraocular «M-flex» lens, 40 - multifocal intraocular «Gradiol» lens, 64 - multifocal intraocular «Accord» lens, 66 - monofocal intraocular lens). Pre-and post-operative examination included visual acuity test (with and without correction to near, far and moderate distances), determination of the nearest point of clear vision, contrast sensitivity study using the «Zebra» software, stereo vision test, pupil diameter measuring, refractometry, keratometry, binocular vision color tests, patient questioning. Pre-operative evaluation was performed 1 day prior to surgery. Post-operative observation was carried out 1 week, 1, 3, 6 and 12 months after the surgery. Results. No statistically significant difference (p 0.05) in uncorrected visual acuity at different light intensity - 102 lux and 416 lux - was found between the groups with different types of multifocal intraocular lenses. In groups with multifocal intraocular lenses light side effects were observed in 46-52.5% of patients. However, there was no link between the light side effects and patients’ satisfaction with results of the surgery. Reduction of spatial contrast sensitivity parameters was registered in all groups of multifocal intraocular lenses patients compared to patients with monofocal intraocular lenses (p 0.05). According to the survey results, 92.5 to 94% of patients with multifocal intraocular lenses did not report decreased visual acuity on moderate distance. Conclusion. The most important reason for patients’ dissatisfaction with the results of the multifocal intraocular lenses implanting was the reduction of spatial-contrast sensitivity parameters. Bilateral multifocal intraocular lenses implanting improved the contrast ratio.

Stereo-Acuity in Patients Implanted with Multifocal Intraocular Lenses: Is the Choice of Stereotest Relevant?

Purpose: A randomized and double-blinded study design was implemented to assess the stereo-acuity in patients symmetrically implanted with four types of multifocal intraocular lenses (MIOLs), compared to a monofocal lens (control group). In addition, the influence of the type of test employed for the evaluation of stereo-acuity was explored.Materials and Methods: Six months after cataract intervention, stereo-acuity was measured with the Titmus and TNO stereotests in 143 patients implanted with one of the following MIOL lens types: hybrid spherical SN60D3, hybrid aspheric SN6AD1, diffractive aspheric ZMA00 and refractive spherical NXG1. A control group implanted with the monofocal aspheric ZA9003 (in which stereo-acuity was measured with a near addition) was also included in the study.Results: Statistically significant better stereo-acuity was found in the monofocal group with both stereotests (except for the SN60D3 group with the Titmus test) (all p < 0.001). No significant differences in stereo-acuity between MIOLs were found using the Titmus test. However, with the TNO, patients implanted with hybrid diffractive MIOLs exhibited statistically significant worse stereo-acuity than those with the refractive design (SN60D3, p < 0.001; SN6AD1, p = 0.006).Conclusions: Patients implanted with MIOLs have worse stereo-acuity than those implanted with monofocal IOLs due to the decrease in retinal image contrast originating in the simultaneous presence of two images. A wavelength-based stereotest such as the TNO induces large differences in image contrast between fellow eyes implanted with diffractive-based MIOLs, which may result in an underestimation of the real stereo-acuity of the patient.

Effect of Decentration on the Optical Performance in Multifocal Intraocular Lenses

Aims: To evaluate the influence of decentration on optical performance in multifocal intraocular lenses (IOLs) using eye models. Methods: This study evaluated 4 types of multifocal IOLs (ReSTOR SA60D3, Alcon; TECNIS Multifocal ZM900, AMO; ReZoom, AMO; SFX-MV1, Hoya). The evaluations were based on measurements of the near and far modulation transfer function (MTF) and visualized actual near images (newspaper) using eye models with the IOL horizontally displaced 0, 0.25, 0.5, 0.75 and 1.0 mm from the center. Results: For the diffractive ReSTOR the near MTF decreased with increasing decentration. The near images (newspaper characters) became difficult to distinguish at a decentration of 1.0 mm. For the diffractive ZM900, the near and far MTFs gradually decreased with increasing decentration. For the refractive ReZoom and SFX-MV1, we observed almost no change in the near MTF from a decentration of 0–1.0 mm. However, the far MTF clearly decreased starting at a decentration of 1.0 mm for ReZoom and 0.75 mm for SFX-MV1. Conclusion: The MTFs and near images are affected to a different extent depending on the design of multifocal IOLs; clinically relevant effects are not to be expected up to a decentration of 0.75 mm.

Visual Function With Bilateral Implantation of Monofocal and Multifocal Intraocular Lenses: A Prospective, Randomized, Controlled Clinical Trial

To evaluate visual function of three types of multifocal intraocular lenses (IOLs) and one monofocal IOL (as the control group) after cataract surgery. One hundred fourteen patients participated in a prospective, randomized, controlled clinical study and received monofocal Tecnis Z9000 (AMO) (n = 24, 48 eyes); symmetric diffractive multifocal Tecnis ZM900 (AMO) (n = 26, 52 eyes); zonal refractive multifocal ReZoom (AMO) (n = 32, 64 eyes); and asymmetric diffractive multifocal TwinSet (Acri.Tec) (n = 32, 64 eyes) IOLs. Mean binocular distance best spectacle-corrected visual acuity (BSCVA) (logMAR) was 0.05 for controls, 0.08 for ZM900, 0.07 for ReZoom, and 0.11 for TwinSet, with mean binocular distance BSCVA at near of 0.49, 0.06, 0.22, and 0.11, respectively. Mean contrast sensitivity was better for the monofocal IOL group than for the multifocal IOLs. Patients assigned to TwinSet had less favorable contrast sensitivity scores. Patients with monofocal IOLs had more frequently recommended near addition (74%) than those with multifocal IOLs. Patients with refractive ReZoom had also recommended near addition more frequently than the two diffractive groups. The percentage of dysphotopsia phenomena was 81% in patients with diffractive multifocal ZM900 compared with 48% in patients with monofocal IOLs, 53% with refractive ReZoom, and 47% with diffractive TwinSet. The monofocal IOL showed better visual function and lesser photic phenomena than multifocal IOLs but patients were spectacle dependent. ReZoom provided better distance BSCVA than the TwinSet diffractive model. Patients with Tecnis and TwinSet diffractive multifocal IOLs were more spectacle independent than patients with ReZoom. Patients with TwinSet had the worst visual function. Patients implanted with the Tecnis diffractive ZM900 were those reporting more photic phenomena.