Journal of Clinical Medicine Article Far and Near Contrast Sensitivity and Quality of Vision with Six Presbyopia Correcting Intraocular Lenses Miguel Á. Gil 1 , Consuelo Varón 2 , Genis Cardona 2, * and José A. Buil 1 1 Ophthalmology Department, Santa Creu and Sant Pau Hospital, Sant Quintí, 89, E08041 Barcelona, Spain; mgila@santpau.cat (M.Á.G.); jbuil@santpau.cat (J.A.B.) 2 Department of Optics and Optometry, Universitat Politècnica de Catalunya, Violinista Vellsolà, 37, E08222 Terrassa, Spain; maria.consuelo.varon@upc.edu * Correspondence: genis.cardona@upc.edu Abstract: The objective of this prospective, randomized, double-masked study was to compare the contrast sensitivity and quality of vision of patients bilaterally implanted with the following six differ- ent presbyopia correcting intraocular lenses (IOLs): SV25T0 (n = 19), ATLISA 809M (n = 18), ATLISA TRI 839MP (n = 19), ZKB00 (n = 20), ZLB00 (n = 20) and Symfony ZXR00 (n = 20). For comparison purposes, 36 patients were implanted with a monofocal lens (ZA9003). Contrast sensitivity was assessed binocularly at distance under photopic, mesopic and mesopic plus glare conditions, and at near under photopic conditions. Quality of vision was explored in terms of photic phenomena and spectacle independence. Overall, the monofocal lens offered better contrast sensitivity, under all illu- mination conditions, and less occurrence and intensity of photic phenomena. Amongst the multifocal IOL (MIOL) designs, the extended depth of focus Symfony ZXR00 provided better contrast sensitivity than the other MIOLs, particularly at intermediate and high spatial frequencies. Up to 40% and 50% of patients implanted with MIOLs reported glare and halos, respectively. The SV25T0 resulted in less occurrence and intensity of halos. The evaluation of photic phenomena and contrast sensitivity Citation: Gil, M.Á.; Varón, C.; under different illumination conditions may reflect real-life, visually challenging situations, and thus Cardona, G.; Buil, J.A. Far and Near provide insightful information to assist ophthalmic surgeons when selecting the best intraocular lens Contrast Sensitivity and Quality of for their patients. Vision with Six Presbyopia Correcting Intraocular Lenses. J. Clin. Keywords: cataract surgery; contrast sensitivity; extended depth of focus; multifocal intraocular lens; Med. 2022, 11, 4150. https://doi.org/ 10.3390/ jcm11144150 quality of vision Academic Editors: Raimo Tuuminen and Piotr Kanclerz Received: 14 June 2022 1. Introduction Accepted: 15 July 2022 Data from 2015 revealed that 78 percent of US households had a desktop or laptop Published: 17 July 2022 computer and 75 percent owned at least a handheld device [1]. Given the ubiquity of Publisher’s Note: MDPI stays neutral technology and displays, recent decades have witnessed a progressive shift in the visual with regard to jurisdictional claims in needs and demands of the elderly population, with a change in the preference of spectacle published maps and institutional affil- independence from near to intermediate distances. Reading text presented on an electronic iations. display is a challenging visual situation in which factors such as size and resolution of visual stimuli, type of task [2] and contrast determine the experience of users. Contrast sensitivity (CS) measurements offer a more complete approach to visual function assessment than that provided solely by high contrast visual acuity (VA). Contrast sensitivity assessment has Copyright: © 2022 by the authors. good sensitivity and specificity for the detection of subtle visual function loss resulting Licensee MDPI, Basel, Switzerland. from multifocal intraocular lens (MIOL) implantation [3–10]. This article is an open access article Overall, MIOLs have been reported to compromise CS, when compared with mono- distributed under the terms and focal designs [3,4,6]. In addition, performance of MIOLs depends on the lens profile conditions of the Creative Commons (aspheric vs. spherical), optics (refractive, diffractive or hybrid), add power, and actual Attribution (CC BY) license (https:// light distribution to distance, near and intermediate foci. Amongst MIOLs, diffractive creativecommons.org/licenses/by/ designs have proved superior to refractive MIOLs in terms of CS, and aspheric profiles 4.0/). J. Clin. Med. 2022, 11, 4150. https://doi.org/10.3390/jcm11144150 https://www.mdpi.com/journal/jcm J. Clin. Med. 2022, 11, 4150 2 of 11 offer a better performance in challenging situations such as driving at night [8–10]. Ex- tended depth of focus (EDOF) designs were introduced to prevent the CS loss encountered with bifocal and trifocal MIOLs [11–14]. In addition, patients implanted with EDOF tend to report less incidence, size and intensity of halos than those with other multifocal designs [12–15]. It must be noted that published literature commonly explores CS under photopic and mesopic conditions, which may not necessarily reflect the daily challenges faced by patients. Accordingly, the published recommendations of the American Academy of Ophthalmology Task Force for EDOF MIOLs stress the need to assess CS with and without glare [15]. The aim of the present study was to explore and compare photopic, mesopic and mesopic with glare distance CS, and near photopic CS, as well as quality of vision, of six different presbyopia lenses, including a trifocal and an EDOF design, and a reference monofocal lens, 6 months after lens implantation. A prospective, randomized, double- masked study was designed for this purpose. 2. Materials and Methods 2.1. Study Sample Participants were recruited from the Ophthalmology Department of Santa Creu and Sant Pau Hospital, Barcelona, Spain, between February 2019 and March 2020. Inclusion criteria were age over 60 years, bilateral cataract and successful intraocular lens (IOL) implantation, potential VA of 0.1 logMAR or better and preoperative corneal astigmatism equal to 1.25 D or less. Patients with a history of glaucoma, ocular fundus abnormalities, severe dry eye, corneal pathologies and traumatism, irregular astigmatism, corneal or intraocular surgery were excluded. Patients presenting surgical complications (zonular luxation or subluxation, posterior capsular rupture), pupillary trauma, vitreous loss and those cases in which the lens could not be placed in the capsular bag were also excluded from the study. Patients reporting high visual demands, such as frequent nighttime driving, or who were not willing to accept a certain level of post-operative photic phenomena were excluded from the MIOLs groups. In contrast, patients giving preference to excellent vision at distance over the need for spectacle use at near and intermediate distances were included in the monofocal group. Patients manifesting difficulties with examinations and those not attending the follow-up visits were excluded from the study. All participants provided written informed consent following a full description of the study. The study followed the Declaration of Helsinki tenets of 1975 (as revised in Tokyo in 2004) and received the approval of the Santa Creu and Sant Pau Hospital Ethical Review Board (n. 2211591). 2.2. Intraocular Lenses Six different IOL designs were implanted in this study, and one monofocal lens (Table 1). IOL implantation order was determined with a 1:1:1:1:1:1 block randomization scheme, using the IBM Statistical Package for the Social Sciences (SPSS) software v.27.0 (IBM Corp. Armonk, NY, USA) for Windows. Given a similar sample size for each IOL group, this randomization ratio resulted in an equal allocation of MIOL interventions. Patients were unaware of the type of MIOL they were implanted, although they knew whether their IOLs were monofocal or multifocal. All IOLs (monofocal and multifocal) were provided free of charge to the patients. J. Clin. Med. 2022, 11, 4150 3 of 11 Table 1. Intraocular lenses used in the study, base power of 20.00 diopters (D). Near (n) and in- termediate (i) add powers correspond to the plane of the lens. Spherical aberration (SA) is for a 6.0 mm pupil. ADD POWER SA LENS MANUFACTURER OPTICAL DESIGN (D) (µm) Bifocal, anterior aspheric apodized Alcon Laboratories, AcrySof ReSTOR SV25T0 +2.5 (n) −0.20 diffractive (3.4 mm) and refractive Fort Worth, TX, USA surface Tecnis ZKB00 Johnson and Johnson +2.75 (n) Bifocal, anterior aspheric and Surgical Vision, Santa −0.27 posterior diffractive surface Tecnis ZLB00 +3.25 (n) Ana, CA ATLISA 809M +3.75 (n) Bifocal, aspheric diffractive Carl Zeiss Meditec AG, −0.18 Jena, Germany +3.33 (n) Trifocal, anterior surface with an ATLISATri 839MP +1.66 (i) aspheric diffractive profile Extended depth of focus, Johnson and Johnson wavefront-designed anterior surface, Tecnis Symfony ZXR00 Surgical Vision, Santa ≈+1.75 (i) −0.27 posterior achromatic diffractive Ana, CA surface with echelette design Johnson and Johnson Tecnis ZA9003 Surgical Vision, Santa - −0.27 Monofocal, anterior aspheric Ana, CA 2.3. Surgical Technique Surgeries were performed by the same experienced surgeon (M.Á.G.). All surgeries, aimed at bilateral emmetropia and consisted of a 2.75 mm clear corneal incision in the steepest corneal meridian, and a secondary paired incision at 180◦ if corneal astigmatism was ≥1.00 D. For corneal astigmatisms under 1.00 D, incisions aimed not to introduce cylinder residual errors. Following phacoemulsification, the recommended injectors were employed to place IOLs in the capsular bag. All patients received interventions in both eyes, with a time interval of one week between the interventions. 2.4. Contrast Sensitivity The CSV-1000 contrast sensitivity test (Vector Vision, Inc, Greenville, OH, USA) was employed to assess distance CS binocularly at 2.5 m, under photopic (85 cd/m2 ) (DCSP), mesopic (5 cd/m2 ) (DCSM) and mesopic with glare (DCSMG) conditions. This test consists of a backlit translucent chart presenting four sine-wave grating stimuli corresponding to spatial frequencies of 3, 6, 12 and 18 cycles per degree (cpd) and eight levels of contrast. Measures, in which a four-alternative forced choice paradigm was implemented, were conducted after allowing patients 5 min to adapt to each illumination level. In turn, the Vistech VCTS 6000 system (Vistech Consultants, Inc, Dayton, OH, USA) was used to assess binocular near photopic contrast sensitivity (NCSP) at 40 cm. This test presents five sine-wave grating stimuli sustaining 1.5, 3, 6, 12 and 18 cpd and eight levels of contrast. Ambient illumination was fixed at approximately 120 cd/m2 , as the Vistech VCTS 6000 is not a backlit test. Patients were permitted small adjustments of their viewing distance, if necessary, to allow for differences in MIOL add power. Near measurements consisted of a two-alternative forced choice paradigm. Patients used their best distance correction for CS evaluation. For near CS assessment, an additional lens of +2.50 D was used in patients implanted with the monofocal lens, which resulted in partial loss of masking for this IOL group. All measurements were performed by the same experienced, masked optometrist, 6 months after the second intervention. J. Clin. Med. 2022, 11, 4150 4 of 11 2.5. Quality of Vision Subjective quality of vision was evaluated by means of a short questionnaire (Supplementary File S1: Quality of vision questionnaire). The aspects under evaluation were spectacle independence for distance, intermediate and near tasks and presence of undesirable photic phenomena such as halos and glare. To ensure a correct and com- plete interpretation of the questions, patients were shown reference images of halos and glare phenomena. 2.6. Data Analysis The IBM SPSS v.27.0 was used for data analysis. The Kolmogorov–Smirnov test disclosed non-normal distributions of some of the quantitative variables. Therefore, median and range values are reported and, to facilitate comparison, mean and standard deviation (SD) values are also presented. The Kruskal–Wallis test was used for multiple comparisons and, when appropriate, pair-wise comparisons were conducted with the Mann–Whitney test. A p-value of 0.05 or less was defined as the cut-off for statistical significance. The DCSP and NCSP values were normalized by dividing the absolute log CS value by the population average reported by Boxer Wachler and Krueger [16] for 3 (2.02 log units), 6 (2.09 log units), 12 (1.85 log units) and 18 (1.45 log units) cpd and photopic conditions. The estimation of the required sample size was based on previous research on contrast sensitivity with MIOLs in which a threshold for clinical significance was set at a difference larger than 0.15 log units within the same spatial frequency [17]. Considering an α-error of 0.05, a β-error of 0.20 and 7 IOL groups, an initial sample size of 14 participants per group was required to detect 0.15 log unit changes in contrast sensitivity (given a SD of ±0.1 log units). 3. Results 3.1. Sample Demographics A total of 152 patients (48 males), age 60 to 86 years, participated in the study. Patients received bilateral and symmetrical implantations of the following IOLs: ATLISA 809M (18 patients), AcrySof ReSTOR SV25T0 (19 patients), Tecnis ZKB00 (20 patients), ATLISA TRI 839MP (19 patients), Tecnis ZLB00 (20 patients), Tecnis Symfony ZXR00 (20 patients) and the monofocal Tecnis ZA9003 (36 patients). Table 2 summarizes demographic data. No statistically significant inter-group differences were found for these variables. All interventions were uneventful and no post-surgical complications were reported. Thus, no patients had to be excluded from the study once the initial allocation was concluded. Table 2. Demographic data for each lens type. Results are displayed as mean ± standard deviation (SD) or frequency (gender), with the outcome of the ANOVA or the Kruskal–Wallis tests (p-value). Pupil diameter was measured under photopic conditions. Lens power and pupil diameter correspond to the right eye. Symfony ATLISA ATLISA ZXR00 SVT250 ZKB00 ZLB00 ZA9003 809M Tri 839MP Extended p Bifocal Bifocal Bifocal Monofocal Bifocal Trifocal Depth of Focus n (eyes) 19 20 20 18 19 20 36 Age (years) 74.3 ± 7.5 68.9 ± 12.9 73.3 ± 4.6 71.6 ± 7.1 68.7 ± 10.3 68.2 ± 6.2 72.1 ± 5.8 0.064 Gender 8/11 5/15 7/13 4/14 4/15 5/15 15/21 0.428 (male/female) IOL power (D) 21.3 ± 2.4 21.6 ± 3.4 22.3 ± 1.7 22.3 ± 2.4 21.9 ± 4.3 21.8 ± 5.7 21.0 ± 3.6 0.832 Pupil diameter 3.2 ± 0.6 3.4 ± 0.7 3.2 ± 0.7 3.0 ± 0.6 3.3 ± 0.8 3.3 ± 0.8 3.1 ± 0.7 0.768 (mm) J. Clin. Med. 2022, 11, 4150 5 of 11 3.2. Contrast Sensitivity Photopic, mesopic, mesopic with glare and near photopic CS values for each lens group are summarized in Table 3 (median logarithmic values and range) and shown in Figure 1 (mean logarithmic values). A Kruskal–Wallis analysis revealed statistically significant between-group differences for all spatial frequencies under evaluation and illumination conditions (all p ≤ 0.001). Overall, the monofocal ZA9003 offered the best performance at all conditions and spatial frequencies, with statistically significant differences between this lens and all MIOLs, with the exception of the Symfony. Indeed, differences between the ZA9003 and the Symfony reached statistical significance only at certain frequencies (6 cpd DCSP, p = 0.003; 12 cpd DCSP, p = 0.022; 3 cpd DCSM, p = 0.028; 3 cpd DCSMG, p = 0.047; 6 cpd DCSMG, p = 0.013; 1.5 cpd NCSP, p = 0.021; 12 cpd NCSP, p = 0.008). Table 3. Contrast sensitivity at distance (2.5 m) under photopic (DCSP), mesopic (DCSM) and mesopic with glare (DCSMG), as well as near (33–40 cm) photopic contrast sensitivity (NCSP). Median, maximum and minimum logarithmic values are presented for each lens group and spatial frequency (in cycles per degree, cpd). Also shown are the outcomes of the Kruskal–Wallis test of statistical significance (p-value). ATLISA ATLISA Symfony Spatial SVT250 ZKB00 ZLB00 Tri ZA9003 809M ZXR00 p Frequency Bifocal Bifocal Bifocal 839MP Monofocal Bifocal EDOF Trifocal 1.63 1.78 1.75 1.78 1.78 1.78 1.93 3 cpd <0.001 1.34–1.93 1.17–1.93 1.34–1.93 1.17–1.93 1.17–1.93 1.49–2.08 1.49–2.08 1.70 1.77 1.70 1.70 1.70 1.84 2.07 6 cpd <0.001 1.38–2.29 1.38–2.29 1.55–1.99 1.21–2.14 1.38–2.14 1.55–2.29 1.70–2.29 DCSP 1.40 1.40 1.40 1.25 1.08 1.69 1.69 12 cpd <0.001 0.91–1.69 0.91–1.99 1.08–1.69 0.31–1.84 0.91–1.84 1.40–1.99 0.91–1.99 0.81 0.96 0.81 0.81 0.64 1.10 1.25 18 cpd <0.001 0.47–1.25 0.47–1.55 0.47–1.25 0.13–1.10 0.13–1.25 0.81–1.55 0.47–1.55 1.49 1.71 1.63 1.63 1.63 1.63 1.78 3 cpd 0.001 1.34–1.93 1.17–2.09 1.34–2.08 1.17–1.93 1.34–1.93 1.34–1.93 1.63–2.08 1.70 1.84 1.70 1.84 1.70 1.84 1.99 6 cpd <0.001 1.55–2.29 1.38–2.14 0.61–2.14 1.38–2.14 1.21–1.99 1.55–2.29 1.55–2.29 DCSM 1.40 1.40 1.25 1.25 1.25 1.69 1.69 12 cpd <0.001 0.91–1.69 0.31–1.69 0.31–1.69 0.91–1.84 0.31–1.69 1.25–1.99 0.91–1.99 0.81 0.89 0.96 0.81 0.81 1.10 1.25 18 cpd <0.001 0.47–1.10 0.47–1.25 0.64–1.25 0.47–1.40 0.13–1.25 0.64–1.55 0.47–1.55 1.56 1.63 1.63 1.63 1.49 1.78 1.78 3 cpd <0.001 1.34–1.93 1.34–1.93 1.17–2.08 1.17–1.93 1.00–1.93 1.34–1.93 1.63–2.08 1.70 1.70 1.84 1.70 1.70 1.99 1.99 6 cpd <0.001 1.55–2.14 1.21–2.14 0.61–2.29 1.38–1.99 1.21–2.14 1.55–2.14 1.70–2.29 DCSMG 1.40 1.40 1.25 1.40 1.25 1.54 1.69 12 cpd <0.001 0.31–1.69 0.31–1.99 0.31–1.69 0.31–1.84 0.91–1.69 1.25–1.99 1.08–1.99 0.81 0.89 0.96 0.81 0.64 1.10 1.25 18 cpd <0.001 0.47–1.25 0.47–1.55 0.64–1.40 0.64–1.55 0.13–1.25 0.64–1.55 0.81–1.55 1.54 1.54 1.54 1.54 1.54 1.85 1.54 1.5 cpd <0.001 1.30–1.54 1.30–1.85 1.30–1.85 1.30–1.85 1.30–1.85 1.30–2.23 1.30–2.08 1.64 1.93 1.64 1.64 1.64 1.93 1.93 3 cpd 0.001 1.38–1.93 1.38–1.93 1.38–2.23 1.38–2.23 1.38–2.23 1.64–2.34 1.38–2.23 NCSP 1.49 1.65 1.65 1.65 1.65 1.85 1.85 6 cpd <0.001 1.32–2.10 1.04–1.85 1.04–1.85 1.32–2.27 1.32–2.10 1.32–2.27 1.32–2.27 1.18 1.51 1.18 1.51 1.51 1.51 1.74 12 cpd <0.001 0.90–1.51 0.70–1.94 0.70–1.74 0.90–1.94 0.90–1.94 0.90–1.94 0.90–2.10 0.85 0.85 1.00 1.00 1.00 1.18 1.18 18 cpd <0.001 0.60–1.18 0.60–1.60 0.60–1.41 0.60–1.41 0.60–1.41 0.60–1.60 0.30–1.81 J. Clin. Med. 2022, 11, x FOR PEER REVIEW 6 of 11 0.90–1.51 0.70–1.94 0.70–1.74 0.90–1.94 0.90–1.94 0.90–1.94 0.90–2.10 J. Clin. Med. 2022, 11, 4150 0.85 0.85 1.00 1.00 1.00 1.18 1.18 6 of 11 18 cpd <0.001 0.60–1.18 0.60–1.60 0.60–1.41 0.60–1.41 0.60–1.41 0.60–1.60 0.30–1.81 Figure Figure 1. 1. Postoperative Postoperativebinocular binocularcorrected correcteddistance distancemean meanloglogcontrast contrastsensitivity sensitivity(CS) (CS)in inphotopic, photopic, mesopic, mesopic with glare and near photopic conditions. mesopic, mesopic with glare and near photopic conditions. Regarding Regarding DCSP, DCSP, statistically statistically significant significant pair-wise pair-wise differences differenceswere wereonlyonlyfound foundbe- be- tween the Symfony and the other MIOLs, with the Symfony tween the Symfony and the other MIOLs, with the Symfony offering better performance offering better performance at at all all spatial spatial frequencies, frequencies, particularly particularly at at 12 12 and and 1818 cpd. cpd. Statistically Statisticallysignificant significantdifferences differences were were found found between betweenthe theSymfony Symfonyand andthetheSV25T0 SV25T0(3(3cpd: cpd:p =p 0.002, = 0.002, 6 cpd: 6 cpd:p = p0.039; = 0.039;12 cpd: p < 0.001, 12 cpd: 18 cpd: p < 0.001, 18 pcpd: = 0.005); the ZKB00 p = 0.005); (12 cpd:(12 the ZKB00 p =cpd: 0.011); p= the ZLB00the 0.011); (6 cpd: ZLB00 p =(60.011, cpd: 12 p cpd: p = 0.003, = 0.011, 12 cpd:18 cpd: p p== 0.008); 0.003, the 18 ATLISA cpd: p 809M (6 cpd:the = 0.008); p = ATLISA 0.019; 12 cpd: 809Mp <(60.001, cpd: 18 cpd: p = 0.002); and the ATLISA TRI 839MP (6 cpd: p = 0.009; p = 0.019; 12 cpd: p < 0.001, 18 cpd: p = 0.002); and the ATLISA TRI 839MP (6 cpd: 12 cpd: p = 0.005, 18 cpd: pp ==0.002). 0.009; 12 cpd: p = 0.005, 18 cpd: p = 0.002). Similar Similar results results were were obtained obtained in in mesopic mesopic conditions, conditions, under under which which thethe Symfony Symfony also also proved a superior proved superior lenslenstotomost mostofofthe theother other MIOLs MIOLs at intermediate at intermediate andandhighhigh spatial frequen- spatial fre- cies, withwith quencies, differences differencesin theinperformance the performance of theofother MIOLs the other MIOLswhen compared when compared pair-wise. pair- Statistical wise. differences Statistical were found differences between were found the Symfony between and the the Symfony andSV25T0 (12 cpd: the SV25T0 (12pcpd: = 0.004, p= 18 cpd: p < 0.001); the ZKB00 (12 cpd: p = 0.011, 18 0.004, 18 cpd: p < 0.001); the ZKB00 (12 cpd: p = 0.011, 18 cpd: p = 0.014); cpd: p = 0.014); the ZLB00 (6 cpd: (6 cpd: pp ==0.019, 0.019,12 cpd: pp==0.001, 12cpd: 0.001,18 cpd:pp==0.017); 18cpd: 0.017);the theATLISA ATLISA809M 809M(12 cpd: pp==0.004, (12cpd: 0.004,1818cpd: cpd: pp==0.003); 0.003);and andthethe ATLISA ATLISA TRITRI 839MP 839MP (6 cpd: (6 cpd: p = 12 p = 0.030; 0.030; cpd: 12 0.001,p18