Cataract is one of the leading causes of preventable blindness all over the world.1 It is commonly treated with phacoemulsification and intraocular lens (IOL) implantation.2 Monofocal IOLs are often used for clear vision at distance and also for monovision.3 With the introduction of multifocal IOLs, the need for spectacles for both distance and near has been reduced.4 AcrySof IQ ReSTOR (Alcon Laboratories, Inc., Fort Worth, TX) has been one of the most commonly used multifocal IOLs for years with its apodized, diffractive, single-piece, hydrophobic acrylic design.5 Although diffractive bifocal IOLs have concentric rings to achieve effective near and distance visual acuity, they are not sufficient at medium distances.6 With the development of trifocal IOLs in recent years, improved visual acuities have been reported at all distances.7
There are various types of trifocal IOLs in clinical use. The Acrysof IQ PanOptix (Alcon Laboratories, Inc.) is a recently developed non-apodized diffractive trifocal IOL with a single-piece, hydrophobic structure and a blue light filter.8 It optimizes the use of light at 120 cm to provide distance vision, while providing effective vision with +2.07 diopters (D) additional power at intermediate distance (60 cm) and +3.25 D additional power at near distance (40 cm). It has a 4.5-mm diameter diffractive zone that reduces dependence on pupil size and lighting conditions.8
In the literature, a limited number of studies have compared the visual performance between trifocal and multifocal IOLs from the same manufacturer using the same IOL platform.9–11 A study compared optical characteristics of the PanOptix and ReSTOR +3.00 D (model SN6AD1; Alcon Laboratories, Inc.) IOLs in laboratory conditions.10 A single clinical study compared visual outcomes of mix-and-match implanted ReSTOR IOLs (SV25T0 = +2.50 D and SN6AD1 = +3.00 D) and bilateral implanted PanOptix IOLs (TFNT00).11 However, to our knowledge, no study has compared the vision-related quality of life (using the Visual Function Index [VF-14]) after mix-and-match implantation of ReSTOR IOLs (+2.50 D/+3.00 D) and bilateral implantation of PanOptix IOLs to date. In addition, no study has compared visual performance of these lenses after performing cataract surgery with femtosecond laser assistance.
In this study, we aimed to evaluate and compare vision-related quality of life (using the VF-14 questionnaire12) and visual acuity, defocus curve, and contrast sensitivity outcomes of mix-and-match implanted ReSTOR IOLs and bilateral implanted PanOptix IOLs after femtosecond laser–assisted cataract surgery (FLACS).
Patients and Methods
This prospective, comparative, non-randomized study included consecutive eyes of patients scheduled to undergo cataract surgery at the Department of Ophthalmology, Bayindir Hospital, Ankara, Turkey, between February 2016 and February 2018 by a single experienced surgeon (YAA). Prior to the study, institutional review board approval was obtained. The study adhered to the tenets of the Declaration of Helsinki.
Inclusion and Exclusion Criteria
All patients who were included in the study had grade 2 to 3 nuclear cataracts graded using the Lens Opacities Classification System III (LOCS III).13 Patients with a history of prior ocular surgery, coexisting ocular inflammation or any ocular disease (eg, uncontrolled glaucoma), corneal astigmatism greater than 1.00 D, and patients who experienced intraoperative complications were not included in this study.
Cataract Surgery Technique
All procedures were performed under topical anesthesia. Femtosecond laser pretreatment (including corneal incisions [a main port from steep axis and two side ports], capsulotomy, and lens fragmentation) was performed with the same LenSx laser platform (Alcon Laboratories, Inc.). Conventional phacoemulsification was subsequently performed with Centurion Vision Systems (Alcon Laboratories, Inc.) using a phaco-chop technique. An IOL was placed in the capsular bag in all cases. Either mix-and-match bifocal IOLs (ReSTOR +2.50 D in the dominant eye and ReSTOR +3.00 D in the non-dominant eye) or bilateral trifocal IOLs (PanOptix) were implanted. The IOLs were selected based on patients' preference. Postoperatively, all patients received the same treatment regimen consisting of a combination of antibiotic, steroid, and non-steroidal anti-inflammatory drops.
Main Outcome Measures
The main outcome measures were manifest refraction, visual acuity, defocus curve, contrast sensitivity, and visual function. The results of the ReSTOR group and PanOptix group were compared. Early Treatment Diabetic Retinopathy Study (ETDRS; Vector Vision, Ltd., Greenville, OH, and Precision Vision, Woodstock, IL) charts were used to determine uncorrected distance visual acuity (UDVA, 4 m), corrected distance visual acuity (CDVA, 4 m), uncorrected intermediate visual acuity (UIVA, 60 cm), and uncorrected near visual acuity (UNVA, 40 cm). Binocular distance-corrected defocus curve testing was performed from −3.00 to +1.00 D in 0.50-D steps under photopic conditions. Photopic and mesopic contrast sensitivities were evaluated using the CC-100 Topcon LCD device (spatial frequencies 3, 6, 12, and 18 cycles per degree [cpd]). Visual function was determined using the VF-14 questionnaire.
The SPSS Statistics program (version 23.0; SPSS, Inc., Chicago, IL) was used to calculate means and standard deviations for all variables. Significant differences between groups with respect to visual acuity, refractive error, aberrations, and contrast sensitivity were determined with paired t tests. Differences were considered statistically significant when P values were less than .05. Power analysis was performed using the G* Power 3.1 program14 to determine whether the sample size was adequate to give statistical reliability.
The study comprised 70 eyes of 35 patients who met the inclusion and exclusion criteria; 30 eyes of 15 patients were included in the ReSTOR group and 40 eyes of 20 patients were included in the PanOptix group. Table 1 shows the demographic information and preoperative measurements of the patients; there was no statistically significant difference between the two groups (P > .05). Significant power for the study was demonstrated for both groups (P > .90).
Patient Demographics and Preoperative Measurements
Mean cataract grade was 2.4 according to the LOCS III grading system for both groups. There was no statistically significant difference in mean cataract grade between groups (P = .88).
Table 2 and Figure 1 show postoperative 6-month visual outcomes of both groups. Distance visual results were similar between groups (no difference with respect to UDVA, CDVA, spherical equivalent, and refractive cylinder) (P > .05), but UIVA and UNVA outcomes were significantly better in the ReSTOR group compared to the PanOptix group (P < .01).
Comparison of 6-Month Postoperative Visual Outcomes Between Groups
Graphs of refractive outcomes for ReSTOR and PanOptix intraocular lens (Alcon Laboratories, Inc., Fort Worth, TX) groups: (A) uncorrected distance visual acuity (UDVA); (B) corrected distance visual acuity (CDVA); (C) uncorrected intermediate visual acuity (UIVA); (D) uncorrected near visual acuity (UIVA); (E) spherical equivalent refraction accuracy; and (F) postoperative refractive cylinder. D = diopters
Figure 2 shows the mean binocular defocus curves obtained in the two groups. The visual acuity was much better in the ReSTOR group compared to the PanOptix group for the defocus levels of −1.00 D (P = .05), −1.50 D (P < .01), −2.00 D (P < .01), −2.50 D (P = .01), and −3.00 D (P = .05).
Mean defocus curves obtained in the ReSTOR and PanOptix intraocular lens (Alcon Laboratories, Inc., Fort Worth, TX) groups. D = diopters
Figure 3 shows postoperative 6-month photopic and mesopic contrast sensitivity outcomes of the PanOptix and ReSTOR groups. The PanOptix group showed significantly higher scores than the ReSTOR group for 12 and 18 cpd in photopic conditions and for 18 cpd in mesopic conditions (P < .05).
(A) Photopic and (B) mesopic contrast sensitivity for the ReSTOR and PanOptix intraocular lens (Alcon Laboratories, Inc., Fort Worth, TX) groups. cpd = cycles per degree
The average VF-14 questionnaire score was 96.84 ± 2.82 in the PanOptix group and 96.62 ± 2.40 in the ReSTOR group at the 6-month follow-up visit (P = .78). Three patients in the PanOptix group and 2 patients in the ReSTOR group achieved a score of 100.
Being independent of spectacles is the increasing desire of many patients with cataract. Therefore, clear uncorrected visual acuity at distance, intermediate, and near is the main goal following phacoemulsification procedures, especially completed with premium IOL implantation.15
According to the literature, an experimental study (in laboratory conditions) showed an improved performance at intermediate distance (range: 60 to 80 cm) and greater than three lines of improvement in resolution at 60, 70, and 80 cm with the PanOptix compared to the ReSTOR +3.00 D IOL.10 Distance and near resolutions were similar between the PanOptix and ReSTOR +3.00 D IOLs for a photopic pupil (3 mm).10 Vilar et al.11 compared visual outcomes of mix-and-match implanted ReSTOR (+2.50 D and +3.00 D) and bilateral implanted PanOptix IOLs, and showed better intermediate visual acuity and contrast sensitivity with PanOptix IOLs. Another study16 using another trifocal IOL (FineVision; PhysIOL, Liége, Belgium) showed better near and intermediate visual acuity with the trifocal IOL compared to a bifocal IOL (ReSTOR). In our study, consistent with the literature, there was no difference in manifest refraction, UDVA, and CDVA between the two groups at the 6-month follow-up visit. With respect to our UIVA and UNVA outcomes, both groups achieved spectacle independence, but the small difference between the groups was statistically significant (better UIVA and UNVA outcomes in the PanOptix group).
In recent years, defocus curve, which is a strong and objective clinical measure of expected vision at all distances, became the most commonly used tool for the evaluation of presbyopia-correcting IOL performance.17 It is also helpful to understand the effects of postoperative residual refractive errors on patient visual acuity.17 Previous studies have compared the defocus curve of different model trifocal IOLs18 and some other studies have compared either the same model or a different model of trifocal and bifocal IOLs.19,20 Most of these studies found better visual acuity at −0.50, −1.00, and −1.50 D with trifocal IOLs compared to bifocal IOLs. Correspondingly, with respect to our defocus curve results, the vision in our study was better with the trifocal IOLs than with the bifocal IOLs over a range of −1.00 to −3.00 D.
Diffractive IOLs have been shown to increase visual disturbances such as halo and glare, and these disturbances are not adequately represented by visual acuity.21,22 Contrast sensitivity is an objective reflection of visual quality. Many studies found that diffractive IOLs have potential to reduce contrast sensitivity.23 However, few studies have explored a contrast sensitivity difference between multifocal and trifocal IOLs. Bilbao-Calabuig et al.16 found no significant differences in contrast sensitivity between the ReSTOR and FineVision IOLs. In contrast, Vilar et al.11 found better contrast sensitivity in higher frequencies in the PanOptix group compared to the mix-and-match ReSTOR group under photopic conditions. In our study, we also found better contrast sensitivity in the PanOptix group than the mix-and-match ReSTOR group for 12 and 18 spatial frequencies in photopic conditions and for 18 spatial frequencies in mesopic conditions.
In addition to the objective tests to assess visual function after implanting these highly demanded IOLs, it is also important to evaluate the patients' satisfaction and quality of life subjectively with questionnaires such as the VF-14.24 However, there are only a few studies in the literature comparing the quality of life of patients who had implanted trifocal and bifocal IOLs. Cochener25 compared VF-14 outcomes of trifocal (FineVision) and bifocal (Tecnis ZMB00 IOL; Abbott Medical Optics, Santa Ana, CA) IOL implantation and found comparable results between the groups. In contrast, in a recent study, the VF-14 questionnaire was used to compare the quality of life of patients after bilateral implantation of diffractive bifocal (AT LISA 809M; Carl Zeiss Meditec, Jena, Germany) and trifocal (AT LISA tri 839MP; Carl Zeiss Meditec) IOLs, and better results were found in the trifocal IOL group (more difficulty in doing fine handwork, cooking, and playing card games in the bifocal IOL group).9 In our study, as a first in the literature, we compared VF-14 outcomes of patients after mix-and-match implantation of ReSTOR IOLs and bilateral implantation of PanOptix IOLs, and found no statistically significant difference between groups (both groups gave similar answers to the questions and overall patient satisfaction was similar).
Our results are limited by the non-randomized study design and the relatively short-term follow-up (6 months). However, to the best of our knowledge, this is the first study to compare visual function outcomes in addition to visual acuity and defocus curve outcomes between the PanOptix and ReSTOR IOLs.
Binocular implanted PanOptix IOLs seem to be more advantageous than mix-and-match implanted ReSTOR IOLs with respect to near and intermediate vision, defocus curve, and contrast sensitivity. However, overall satisfaction and spectacle independence were similar between groups.
- Brian G, Taylor H. Cataract blindness: challenges for the 21st century. Bull World Health Organiz. 2001;79:249–256.
- Taylor HR, Keeffe JE. World blindness: a 21st century perspective. Br J Ophthalmol. 2001;85:261–266. doi:10.1136/bjo.85.3.261 [CrossRef]
- Greenbaum S. Monovision pseudophakia. J Cataract Refract Surg. 2002;28:1439–1443. doi:10.1016/S0886-3350(02)01218-X [CrossRef]
- Yildirim Karabag R, Günenç Ü, Aydin R, Arikan G, Aslankara H. Visual results following implantation of a refractive multifocal intraocular lens in one eye and a diffractive in the contralateral eye. Turk J Ophthalmol. 2018;48:6–14. doi:10.4274/tjo.56588 [CrossRef]
- Mastropasqua R, Pedrotti E, Passilongo M, Parisi G, Marchesoni I, Marchini G. Long-term visual function and patient satisfaction after bilateral implantation and combination of two similar multifocal IOLs. J Refract Surg. 2015;31:308–314. Erratum in: J Refract Surg. 2015;31:522. doi:10.3928/1081597X-20150423-04 [CrossRef]
- de Vries NE, Nuijts RM. Multifocal intraocular lenses in cataract surgery: literature review of benefits and side effects. J Cataract Refract Surg. 2013;39:268–278. doi:10.1016/j.jcrs.2012.12.002 [CrossRef]
- Cochener B, Vryghem J, Rozot P, et al. Clinical outcomes with a trifocal intraocular lens: a multicenter study. J Refract Surg. 2014;30:762–768. doi:10.3928/1081597X-20141021-08 [CrossRef]
- Kohnen T. First implantation of a diffractive quadrafocal (trifocal) intraocular lens. J Cataract Refract Surg. 2015;41:2330–2332. doi:10.1016/j.jcrs.2015.11.012 [CrossRef]
- Liu X, Xie L, Huang Y. Comparison of visual performance after implantation of bifocal and trifocal intraocular lenses having an identical platform. J Refract Surg. 2018;34:273–280. doi:10.3928/1081597X-20180214-01 [CrossRef]
- Lee S, Choi M, Xu Z, Zhao Z, Alexander E, Liu Y. Optical bench performance of a novel trifocal intraocular lens compared with a multifocal intraocular lens. Clin Ophthalmol. 2016;10:1031–1038. doi:10.2147/OPTH.S106646 [CrossRef]
- Vilar C, Hida WT, de Medeiros AL, et al. Comparison between bilateral implantation of a trifocal intraocular lens and blended implantation of a two bifocal intraocular lenses. Clin Ophthalmol. 2017;11:1393–1397. doi:10.2147/OPTH.S139909 [CrossRef]
- Steinberg EP, Tielsch JM, Schein OD, et al. The VF-14: an index of functional impairment in patients with cataract. Arch Ophthalmol. 1994;112:630–638. doi:10.1001/archopht.1994.01090170074026 [CrossRef]
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- Bilbao-Calabuig R, González-López F, Amparo F, Alvarez G, Patel SR, Llovet-Osuna F. Comparison between mix-and-match implantation of bifocal intraocular lenses and bilateral implantation of trifocal intraocular lenses. J Refract Surg. 2016;32:659–663. doi:10.3928/1081597X-20160630-01 [CrossRef]
- Plaza-Puche AB, Alió JL. Analysis of defocus curves of different modern multifocal intraocular lenses. Eur J Ophthalmol. 2016;26:412–417. doi:10.5301/ejo.5000780 [CrossRef]
- Gundersen KG, Potvin R. Trifocal intraocular lenses: a comparison of the visual performance and quality of vision provided by two different lens designs. Clin Ophthalmol. 2017;11:1081–1087. doi:10.2147/OPTH.S136164 [CrossRef]
- Mojzis P, Kukuckova L, Majerova K, Liehneova K, Piñero DP. Comparative analysis of the visual performance after cataract surgery with implantation of a bifocal or trifocal diffractive IOL. J Refract Surg. 2014;30:666–672. doi:10.3928/1081597X-20140903-06 [CrossRef]
- Jin S, Friedman DS, Cao K, et al. Comparison of postoperative visual performance between bifocal and trifocal intraocular lens based on randomized controlled trails: a meta-analysis. BMC Ophthalmol. 2019;19:78. doi:10.1186/s12886-019-1078-1 [CrossRef]
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- Akman A, Asena L, Ozturk C, Gür Güngör S. Evaluation of quality of life after implantation of a new trifocal intraocular lens. J Cataract Refract Surg. 2019;45:130–134. doi:10.1016/j.jcrs.2018.12.003 [CrossRef]
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Patient Demographics and Preoperative Measurementsa
|Characteristic||ReSTOR Group (n = 15)||PanOptix Group (n = 20)||P|
|Age (years), mean ± SD||68.0 ± 7.03||66.9 ± 6.65||.26|
|Preoperative topographic cylinder (D)||0.60 ± 0.26||0.56 ± 0.32||.56|
|Anterior chamber depth (mm)||3.24 ± 0.29||3.22 ± 0.30||.87|
|Axial length (mm)||23.27 ± 0.39||23.31 ± 0.91||.83|
Comparison of 6-Month Postoperative Visual Outcomes Between Groupsa
|Outcome||ReSTOR Group (n = 15)||PanOptix Group (n = 20)||P|
|UDVA (logMAR)||−0.06 ± 0.08||−0.14 ± 0.05||.08|
|CDVA (logMAR)||−0.07 ± 0.08||−0.14 ± 0.05||.12|
|UIVA (logMAR)||0.25 ± 0.16||0.03 ± 0.05||< .01|
|UNVA (logMAR)||0.07 ± 0.05||0.00 ± 0.00||< .01|
|Spherical equivalent (D)||−0.14 ± 0.23||−0.10 ± 0.17||.51|
|Refractive cylinder (D)||−0.36 ± 0.30||−0.31 ± 0.22||.51|