Purpose
To compare monocular and binocular mesopic contrast sensitivity and through focus following monocular implantation with KAMRA small-aperture inlay (AcuFocus, Irvine, California, USA) vs binocular implantation with an accommodating or multifocal intraocular lens (IOL) implant.
Design
Three-treatment randomized clinical trial of presbyopia-correcting IOLs with comparison to results from a previous nonrandomized multicenter clinical trial on the KAMRA corneal inlay.
Methods
Study population of 507 subjects with KAMRA inlays; predetermined subgroups included 327 subjects that underwent contrast sensitivity testing and another 114 subjects for defocus curve testing, along with 78 subjects randomized between bilateral Crystalens Advanced Optics (AO) (Bausch + Lomb Surgical, Aliso Viejo, California, USA), AcrySof IQ ReSTOR +3.0 D (Alcon Laboratories, Fort Worth, Texas, USA), or Tecnis +4D Multifocal (MF) (Abbott Medical Optics, Santa Ana, California, USA) IOL.
Results
KAMRA inlay subjects demonstrated improved intermediate and near vision with minimal to no change to distance vision, better contrast sensitivity in the inlay eye when compared to the multifocals, and better binocular contrast sensitivity when compared to all 3 intraocular lenses. Crystalens AO was superior in uncorrected intermediate vision compared to the KAMRA inlay, but not in distance-corrected intermediate, and was worse in near vision. The multifocals were superior in near vision at their respective optimum near focus points, but worse in intermediate vision compared to both KAMRA inlay and Crystalens AO.
Conclusions
The demonstrated performance of these devices should be considered, along with subjects’ visual demands and expectations, degree of crystalline lens dysfunction, and other ocular characteristics, in guiding the selection of small-aperture corneal inlay or specific intraocular lens in the correction of presbyopia.
Presbyopia is a direct consequence of the age-related loss of accommodation resulting from the crystalline lens’s inability to focus at near vergence. The global prevalence of presbyopia is predicted to increase to 1.4 billion by 2020 and to 1.8 billion by 2050. A corneal-based surgical approach to presbyopia can be achieved by monocularly implanting a small-aperture intracorneal inlay into a lamellar pocket in the nondominant eye (KAMRA inlay; AcuFocus, Irvine, California, USA). The KAMRA corneal inlay is designed to provide increased depth of focus by blocking unfocused peripheral light rays and reducing the size of the blur circle. The increased depth of focus provides an extended range of continuous vision expanding from near to intermediate to far. Two-year follow-up on 24 subjects from 1 site in the US IDE clinical trial on the KAMRA inlay showed a mean uncorrected near and intermediate vision of 20/25 and uncorrected distance vision of 20/20 in the implanted nondominant eye. Multifocal and accommodating intraocular lens (IOL) designs have been developed to address presbyopia following cataract or clear lens extraction. Multifocal IOLs distribute light among multiple energy foci for near and far distances, thereby improving near visual acuity over the standard monofocal IOL. Potential disadvantages of this design include reduction in contrast sensitivity, degraded image quality, and increased visual symptoms such as glare/haloes. Accommodating IOLs have a single focal point and they have shown moderate, at times variable, near visual benefit, with improved intermediate vision.
Contrast sensitivity (CS) or low-contrast visual acuity testing under different lighting conditions provides important information about quality of vision. In a recent study, Pepose and associates compared 3 widely-used premium IOLs, Crystalens Advanced Optics (AO) accommodative IOL (Bausch + Lomb Surgical, Aliso Viejo, California, USA), AcrySof IQ ReSTOR +3.0 D multifocal IOL (Alcon Laboratories, Fort Worth, Texas, USA) and AMO Tecnis +4D Multifocal (MF) IOL (Abbott Medical Optics, Santa Ana, California, USA). In that study, Crystalens AO subjects showed better uncorrected and distance-corrected intermediate vision and less optical scatter than subjects implanted with either multifocal IOL and showed fewer visual symptoms and photic phenomena than subjects with Tecnis +4D MF. In distinction, the multifocal IOL subjects showed better distance-corrected near vision. Crystalens AO and ReSTOR +3.0 subjects demonstrated better monocular and binocular mesopic CS without glare at low to mid spatial frequencies when compared to Tecnis +4D MF IOL. The purpose of the current study is to compare the mesopic monocular and binocular CS functions as well as quantitative visual metrics and defocus curve measurements of the KAMRA corneal inlay to the 3 presbyopia-correcting IOLs.
Methods
The monocular and binocular mesopic CS functions, visual acuities, and defocus curves from a nonrandomized multicenter US IDE clinical trial ( http://www.clinicaltrials.gov , NCT00819299 and NCT00850031 ) on the KAMRA corneal inlay were compared to data from a previous 3-treatment randomized clinical trial of presbyopia-correcting IOLs ( http://www.clinicaltrials.gov , NCT01122576 ). The study was performed in accordance with the Declaration of Helsinki and approved by the Ethics Committees of the respective investigational sites. Subjects were screened for eligibility, and informed consents were obtained from all eligible subjects.
In the multicenter clinical trial on the KAMRA inlay 507 subjects at 24 clinical sites were monocularly implanted with the intracorneal KAMRA inlay (ACI7000PDT) in their nondominant eye. The clinical trial sites were located in the following countries: United States, Philippines, Singapore, New Zealand, Australia, Germany, Austria, and United Kingdom. Subjects were screened for eligibility, and informed consents were obtained on all eligible subjects. Naturally emmetropic presbyopic subjects between 45 and 60 years of age, with preoperative spherical equivalent refraction of −0.75 diopter (D) to +0.50 D with no more than 0.75 D of refractive cylinder as determined by cycloplegic refraction, uncorrected near vision worse than 20/40 and better than 20/100, and best-corrected distance visual acuity 20/20 or better in both eyes were enrolled. Key exclusion criteria were previous ocular surgery, anterior or posterior segment disease or degeneration, immunosuppressive disorders, subjects using systemic medications with significant ocular side effects, subjects with latent hyperopia, subjects with intraocular pressure (IOP) >21 mm Hg, and dry eyes. Contrast sensitivity testing was done in a predetermined subgroup, which had 327 subjects tested at 6 months postoperatively. Defocus curve testing was done in another predetermined subgroup, which had 114 subjects tested at 12 months postoperatively. The subgroups were chosen before study initiation.
The multifocal IOL comparative group included 78 subjects randomly assigned to 1 of 3 groups and bilaterally implanted. The subjects and the clinic personnel performing the assessments were masked to the IOL type until study exit. Twenty-six subjects were implanted with the Crystalens AO IOL, 25 subjects were implanted with the ReSTOR +3.0 IOL, and 22 subjects were implanted with the Tecnis +4D MF IOL. These subjects were between 59.8 and 68 years of age. For Crystalens AO, the dominant eye was targeted between plano and −0.25 D and the nondominant eye was targeted between plano and −0.50 D. For ReSTOR +3.0, emmetropia was targeted in both eyes and for Tecnis +4D MF both eyes were targeted for plano to −0.25 D.
Corneal Inlay and Surgical Technique
The appearance of the inlay from the anterior perspective is shown in Figure 1 . The KAMRA corneal inlay is made from a highly biocompatible material, polyvinylidene difluoride (PVDF), and is proven to be stable in the eye. The inlay has a 1.6 mm inside diameter and a 3.8 mm outside diameter; it is 6 μm thick. These holes are responsible for creating a visible light transmission of approximately 5% through the annulus of the inlay. The inlay was placed on the stromal bed and into the lamellar pocket of the nondominant eye. The surgical preparation and technique have been described in detail in prior publications.
Visual Acuity
Visual acuities were measured using the Optec 6500 Vision Tester (Stereo Optical Company, Inc, Chicago, Illinois, USA) and high-contrast visual acuity charts. Visual acuities were recorded by the number of ETDRS letters, and were converted to logarithm of the minimal angle of resolution (logMAR) for all data analysis of averages and standard deviations, and were converted to Snellen to count the cumulative proportions. Comparisons between the KAMRA inlay and the 3 IOLs on monocular and binocular uncorrected distance (UDVA) at 6 m (20 ft), uncorrected intermediate (UIVA) at 80 cm (32 in), uncorrected near (UNVA) at 40 cm (16 in), distance corrected intermediate (DIVA), distance corrected near (DNVA), and best-corrected distance (BDVA) visual acuities at 6 months will be presented. The only difference in testing technique is that the visual acuities were measured up to 60 letters (20/12.5) in the IOL subjects vs 55 letters (20/16) in the KAMRA inlay subjects.
Contrast Sensitivity and Defocus Curve Testing
The CS testing was performed on a subgroup of 327 subjects among the KAMRA inlay study cohort from 18 sites at 6 months and on all the IOL subjects between 4 and 6 months postoperatively with their best-corrected distance correction. CS was measured with the F.A.C.T. (Functional Acuity Contrast Test) chart in the Optec 6500 Vision Tester (Stereo Optical Company), calibrated at a luminance of 85 cd/m 2 and 3 cd/m 2 (±5% per manufacturer’s guidelines) for photopic and mesopic testing, respectively. Mesopic CS with and without glare were tested at frequencies 1.5, 3, 6, and 12 cycles/degree (cpd). For KAMRA inlay subjects, the monocular mesopic with glare condition was added to the study procedure after 24 months into the study and was thus performed on a smaller subgroup of 142 subjects at 36 months only. The ceiling and floor effects of the F.A.C.T. chart are well documented in the published literature. The impact of the floor effect of not seeing any CS patches was taken into consideration in the current study by assigning a value of 0.3 log CS below the first patch (highest-contrast patch) to KAMRA inlay subjects who were not able to identify any patches. In this way, a more accurate estimate of mean CS across subjects can be determined, compared to either assigning a zero value, which would result in an underestimation of mean CS, or assigning the lowest CS value or leaving it as blank, which would result in an overestimation of mean CS. Since we are comparing the KAMRA inlay subjects to the IOL subjects, we applied the same analysis method of assigning 0.3 log CS below the first patch to the IOL subjects who were not able to identify any contrast testing patches. In the KAMRA inlay study, defocus curves were performed on a subgroup of 114 subjects on their implanted eyes while viewing ETDRS charts calibrated for 4 m testing distance in standard photopic conditions, using the best-corrected distance refraction. Visual acuity measurements were obtained for +5.00 D to −5.00 D of defocus at 0.50 D increments. The IOL subjects were tested for +4.00 D to −4.0 D of defocus. Visual acuity measurements were obtained through each successive increment of additional −0.50 D lenses.
Statistical Analysis
Statistical analysis was performed using the JMP statistical package (SAS Institute, Inc, Cary, North Carolina, USA). Statistical significance for continuous parameters was determined by performing pair-wise comparisons using the nonparametric Wilcoxon-Mann-Whitney rank sum tests and corresponding Hodges-Lehman confidence intervals. Categorical parameters were compared by Pearson χ 2 test. Multivariate analysis was conducted on the area under log CS function (AULCSF) using standard least squares method with mixed models including the fixed effect of lens type, age, sex, UDVA, and BDVA at 6 months and the random effect of subject nested within inlay or lens type. AULCSF data were shown to be approximately normally distributed. A P value less than .05 was considered statistically significant. P values have not been adjusted for multiple comparisons.
Results
Demographics and Manifest Refraction
Baseline demographics and 6-month manifest sphere, cylinder, and refractive spherical equivalent (MRSE) data are summarized in Table 1 . The KAMRA inlay subjects (N = 327) with mean age 51.5 ± 3.6 years were significantly younger than the 3 IOL groups, whose average ages were above 63 years ( P < .0001). There was a sex distribution difference in that the IOL groups all had more female than male subjects, whereas the KAMRA inlay group had roughly equal numbers of women and men. The MRSE was significantly different among the KAMRA inlay group and the IOL groups, as the KAMRA inlay group was close to half a diopter hyperopic, Crystalens AO group slightly myopic, and ReSTOR +3.0 and Tecnis +4D MF groups close to plano. Note that KAMRA inlay subjects in the clinical trial were enrolled as emmetropic subjects with a range of MRSE from −0.75 D to 0.5 D in the nondominant eye to be implanted with no refraction correction, while the Crystalens AO subjects were targeted for between plano and −0.25 D in the dominant eye and slightly myopic outcomes in the nondominant eye (up to −0.5 D), compared to the ReSTOR +3.0, targeting emmetropia in both eyes, and Tecnis +4D MF, targeting plano to −0.25 D in both eyes.
| Demographics (By Subjects) | KAMRA | Crystalens AO | ReSTOR +3.0 | Tecnis +4D MF | P Value |
|---|---|---|---|---|---|
| N = 327 | N = 26 | N = 25 | N = 22 | ||
| Age (y) | <.0001 | ||||
| Mean (SD) | 51.5 (3.6) | 63.4 (5.8) | 65.4 (6.2) | 63.6 (8.8) | |
| Min, max | 45, 60 | 53, 73 | 54, 76 | 43, 81 | |
| 95% CI | 51.1–51.9 | 61.1–65.8 | 62.8–68.0 | 59.8–67.5 | |
| Sex (n, %) | .0172 | ||||
| Female | 155 (47.4) | 17 (65.4) | 14 (56.0) | 17 (77.3) | |
| Male | 172 (52.5) | 9 (34.6) | 11 (44.0) | 5 (22.7) | |
| Race (n, %) | .8413 | ||||
| White | 297 (90.8) | 26 (100) | 25 (100) | 22 (100) | |
| Asian | 21 (6.4) | 0 (0) | 0 (0) | 0 (0) | |
| Black | 1 (0.3) | 0 (0) | 0 (0) | 0 (0) | |
| Hispanic | 5 (1.5) | 0 (0) | 0 (0) | 0 (0) | |
| Other | 3 (0.9) | 0 (0) | 0 (0) | 0 (0) | |
| 6 months (by eyes) | N = 327 | N = 52 | N = 50 | N = 44 | |
| MRSE | <.0001 | ||||
| Mean (SD) | 0.48 (0.75) | −0.34 (0.45) | 0.15 (0.37) | −0.12 (0.32) | |
| Min, max | −2.50, 3.00 | −1.25, 0.875 | −0.75, 0.875 | −0.625, 0.50 | |
| 95% CI | 0.40–0.56 | −0.47 to −0.21 | 0.04–0.25 | −0.22 to −0.02 | |
| Sphere | <.0001 | ||||
| Mean (SD) | 0.68 (0.80) | −0.07 (0.47) | 0.44 (0.38) | 0.11 (0.35) | |
| Min, max | −2.50, 3.25 | −1.00, 1.00 | −0.50, 1.25 | −0.50, 0.75 | |
| 95% CI | 0.60 to 0.77 | −0.20 to 0.06 | 0.33 to 0.55 | 0.00 to 0.22 | |
| Cylinder | .6935 | ||||
| Mean (SD) | −0.41 (0.42) | −0.54 (0.32) | −0.58 (0.30) | −0.46 (0.34) | |
| Min, max | −2.75, −0.25 | −1.50, −0.25 | −1.25, −0.25 | −1.50, −0.25 | |
| 95% CI | −0.67 to −0.57 | −0.66 to −0.49 | −0.70 to −0.54 | −0.67 to −0.46 |
Monocular Uncorrected Distance, Intermediate, and Near Visual Acuity
Figure 2 (Left, Center, and Right) shows cumulative percentage and mean monocular UDVA, UIVA, and UNVA. KAMRA inlay ( P = .0008) and ReSTOR +3.0 eyes ( P = .0030) had significantly better UDVA than Crystalens AO eyes. There were no other differences between the other lens pairs. A total of 98% of ReSTOR +3.0, 96.9% of KAMRA inlay, 93.2% of Tecnis +4D MF. and 88.5% of Crystalens AO eyes achieved 20/40 or better UDVA. In interpreting these data, note that the nondominant eye in the Crystalens group could be targeted up to −0.50 D myopia. At 6 months, the Crystalens eyes were slightly myopic and KAMRA inlay eyes were slightly hyperopic, while the ReSTOR +3.0 and Tecnis +4D MF eyes were close to plano ( Table 1 ). UIVA in KAMRA inlay eyes was significantly better than ReSTOR +3.0 eyes ( P = .0156). Crystalens AO eyes were significantly better than KAMRA inlay, ReSTOR +3.0, and Tecnis +4D MF eyes (all P < .0001). There was no significant difference between ReSTOR +3.0 and Tecnis +4D MF eyes ( P = .6408) or between KAMRA and Tecnis +4D MF eyes ( P = .2006). In comparison, 90.4% of Crystalens AO, 85.9% of KAMRA inlay, 75% of Tecnis +4D MF, and 74% of ReSTOR +3.0 eyes achieved 20/40 or better UIVA. UNVA in KAMRA inlay eyes was significantly better than in Crystalens AO eyes ( P = .0191). There was no significant difference between Tecnis +4D MF vs KAMRA inlay ( P = .5110) or Crystalens AO ( P = .0706) eyes when measured at 40 cm. ReSTOR +3.0 eyes had significantly better UNVA when compared to KAMRA inlay, Tecnis +4D MF, and Crystalens AO eyes (all P < .0001). A total of 98% of ReSTOR +3.0, 80.7% of KAMRA inlay, 79.5% of Tecnis +4D MF, and 67% of Crystalens AO eyes achieved 20/40 or better UNVA measured at 40 cm, which is not the optimal near focal point of the Tecnis +4D MF IOL.
Binocular Uncorrected Distance, Intermediate, and Near Visual Acuity
Figure 3 (Left, Center, and Right) shows cumulative percentage and mean binocular UDVA, UIVA, and UNVA. KAMRA inlay subjects were significantly better when compared to Crystalens ( P < .0001) and ReSTOR +3.0 ( P = .0068). There was no significant difference between the IOLs. One hundred percent of ReSTOR +3.0, KAMRA inlay, Tecnis +4D MF, and Crystalens AO subjects achieved 20/40 or better binocular UDVA.
KAMRA inlay subjects had significantly better binocular UIVA when compared to ReSTOR +3.0 ( P = .0020) and Tecnis +4D MF subjects ( P = .0024). Crystalens AO subjects were significantly better than KAMRA inlay ( P = .0002), ReSTOR +3.0 ( P < .0001), and Tecnis +4D MF subjects ( P < .0001). There was no significant difference between ReSTOR +3.0 and Tecnis +4D MF subjects ( P = .8389). One hundred percent of Crystalens AO, 97.2% of KAMRA inlay, 88% of ReSTOR +3.0, and 81.8% of Tecnis +4D MF subjects achieved 20/40 or better binocular UIVA. Both ReSTOR +3.0 and Tecnis +4D MF subjects had significantly better binocular UNVA when compared to KAMRA inlay ( P < .0001 and P = .0024) and Crystalens AO subjects ( P < .0001 and P = .0220). There was no significant difference between Crystalens AO and KAMRA inlay subjects ( P = .9354). One hundred percent of ReSTOR +3.0, 95.5% of Tecnis +4D MF, 92.3% of Crystalens AO, and 90.5% of KAMRA inlay subjects achieved 20/40 or better binocular UNVA.
Monocular Distance-Corrected Intermediate and Near Visual Acuity
Distance-corrected visual acuities were measured at distance, intermediate, and near to account for any residual refractive error and its pseudo-accommodative effects. Figure 4 (Left, Center, and Right) shows cumulative percentage and mean monocular BDVA, DIVA, and DNVA. All lens groups had a mean BDVA above 20/20. One hundred percent of KAMRA inlay, Crystalens AO, and Tecnis +4D MF eyes and 98.0% of ReSTOR +3.0 eyes achieved 20/40 or better BDVA. There was no significant difference between the IOLs on mean BDVA. Crystalens, ReSTOR +3.0, and Tecnis +4D MF eyes all had significantly higher mean BDVA than KAMRA inlay eyes ( P < .0001, P < .0001, P = .0285, respectively). However, the difference between the IOL groups and the KAMRA inlay group is likely largely attributable to the difference in testing ceilings, as the KAMRA inlay group was measured up to 55 letters (−0.1 logMAR) whereas the IOL groups were measured up to 60 letters (−0.2 logMAR). KAMRA inlay eyes had significantly better DIVA than Crystalens AO, ReSTOR +3.0, and Tecnis +4D MF eyes (all P < .0001). Crystalens AO eyes were significantly better than ReSTOR +3.0 and Tecnis +4D MF eyes (both P < .0001). There was no significant difference between ReSTOR +3.0 and Tecnis +4D MF eyes ( P = .2502). In comparison, 95.4% of KAMRA inlay, 92.3% of Crystalens AO, 66% of ReSTOR +3.0, and 61.3% of Tecnis +4D MF eyes achieved 20/40 or better DIVA. KAMRA inlay eyes had significantly better DNVA than Crystalens AO eyes ( P < .0001). There was no significant difference between Tecnis +4D MF and KAMRA inlay eyes ( P = .4795). ReSTOR +3.0 had significantly better DNVA at 40 cm when compared to KAMRA inlay, Crystalens AO, and Tecnis +4D MF eyes (all P < .0001). At 6 months, 98% of ReSTOR +3.0, 88.9% of KAMRA inlay, 88.6% of Tecnis +4D MF, and 40.4% of Crystalens AO eyes achieved 20/40 or better DNVA.
Binocular Distance-Corrected Intermediate and Near Visual Acuity
Figure 5 (Left and Right) shows cumulative percentage and mean binocular DIVA and DNVA. KAMRA inlay had significantly better binocular DIVA than Crystalens AO ( P = .0081) and ReSTOR +3.0 and Tecnis +4D MF subjects (both P < .0001). Crystalens AO had better binocular DIVA than ReSTOR +3.0 ( P < .0001) and Tecnis +4D MF subjects ( P = .0001). There was no significant difference between ReSTOR +3.0 and Tecnis +4D MF subjects ( P = .8386). One hundred percent of Crystalens AO, 98.8% of KAMRA inlay, 90.9% of Tecnis +4D MF, and 88.0% of ReSTOR +3.0 subjects achieved 20/40 or better binocular DIVA. Both ReSTOR +3.0 and Tecnis +4D MF had significantly better binocular DNVA when compared to KAMRA inlay ( P < .0001 and P = .0048) and Crystalens AO subjects (both P < .0001). KAMRA inlay had significantly better binocular DNVA than Crystalens AO subjects ( P < .0001). One hundred percent of ReSTOR +3.0, 97.6% of KAMRA inlay, 95.5% of Tecnis +4D MF, and 84.6% of Crystalens AO subjects achieved 20/40 or better binocular DNVA. For mean binocular BDVA at 6 months, inlay and all lens groups had mean binocular BDVA of 20/16 or better. One hundred percent of subjects in each lens group achieved 20/40 or better binocular BDVA.
Defocus Curve
Figure 6 shows the mean monocular defocus curves determined with the best distance correction at 6 months postoperatively for the IOL groups and at 12 months postoperatively for the KAMRA inlay group. KAMRA inlay performed better at the intermediate dioptric range of −0.50 D to −1.0 D when compared to ReSTOR +3.0 and from −0.50 D to −1.5 D when compared to Tecnis +4D MF. KAMRA inlay performed better than Crystalens AO over a larger dioptric range of −1.0 D to −4.0 D. ReSTOR +3.0 and Tecnis +4D MF IOLs performed best at near dioptric range of −2.5 D to −4.0 D.
Monocular Mesopic Contrast Sensitivity in Without- and With-Glare Conditions
Figure 7 (Left and Right) shows monocular mesopic CS in without- and with-glare conditions. For monocular mesopic CS without glare, KAMRA inlay eyes were significantly better than Crystalens AO eyes at 1.5 and 3 cpd ( P = .0092 and P = .0393, respectively), better than ReSTOR +3.0 eyes at 12 cpd ( P = .0435), and better than Tecnis +4D MF eyes at 1.5, 3, 6, and 12 cpd ( P < .0001, P < .0001, P = .0392, and P < .0001, respectively). There was no significant difference between Crystalens AO and ReSTOR +3.0 eyes at any spatial frequency. Crystalens AO eyes were significantly better than Tecnis +4D MF eyes at 1.5, 3.0, and 12 cpd ( P = .0027, P = .0053, and P = .0071, respectively). ReSTOR +3.0 eyes were significantly better compared to Tecnis +4D MF eyes at 1.5, 3, and 12 cpd ( P < .0001, P < .0001, P = .0193, respectively). For monocular mesopic CS with glare, KAMRA eyes were significantly better than Crystalens AO eyes at 12 cpd ( P = .0187), better than ReSTOR +3.0 eyes at 12 cpd ( P = .0001), and better than Tecnis +4D MF eyes at 1.5, 3, 6, and 12 cpd ( P < .0001, P = .0006, P = .0008, and P < .0001, respectively). There was no significant difference between Crystalens AO and ReSTOR +3.0 eyes at any spatial frequency. Crystalens AO eyes were significantly better than Tecnis +4D MF eyes at 1.5, 3, 6, and 12 cpd ( P = .0027, P = .0009, P < .0001, and P = .0200, respectively). ReSTOR +3.0 eyes were significantly better compared to Tecnis +4D MF eyes at 1.5, 3, and 6 cpd ( P = .0001, P = .0271, P = .0313, respectively).
