Abstract
Purpose:
To compare the clinical outcomes of diffractive multifocal and monofocal lenses in post-laser in situ keratomileusis (LASIK) patients who underwent cataract surgery.
Methods:
This was a retrospective, comparative study of clinical outcomes that was conducted at a referral medical center. Post-LASIK patients who underwent uncomplicated cataract surgery and received either diffractive multifocal or monofocal lens were studied. Visual acuities were compared at baseline and postoperatively. The intraocular lens (IOL) power was calculated with Barrett True-K Formula only.
Results:
At baseline, both groups had comparable age, gender, and an equal distribution hyperopic and myopic LASIK. A significantly higher percentage of patients receiving diffractive lenses achieved uncorrected distance visual acuity (UCDVA) of 20/25 or better (80 of 93 eyes, 86% vs. 36 of 82 eyes, 43.9%, P = 1.0 x 105) and uncorrected near vision of J1 or better (63% vs. 0) compared to the monofocal group. The residual refractive error had no significant difference (0.37 ± 0.39 vs. 0.44 ± 0.39, respectively, P = 0.16) in these two groups. However, more eyes in the diffractive group achieved UCDVA of 20/25 or better with residual refractive error of 0.25–0.5 D (36 of 42 eyes, 86% vs. 15 of 24 eyes, 63%, P = 0.032) or 0.75–1.5 D (15 of 21 eyes, 23% vs. 0 of 22 eyes, P = 1.0 x 10−5) compared to the monofocal group.
Conclusion:
This pilot study shows that patients with a history of LASIK who undergo cataract surgery with a diffractive multifocal lens are not inferior to those who receive monofocal lens. Post-LASIK patients with diffractive lens are more likely to achieve not only excellent near vision, but also potentially better UCDVA, regardless of the residual refractive error.
Keywords: Cataract surgery, diffractive lens, monofocal lens, multifocal lens, post-LASIK
Laser in situ keratomileusis (LASIK) is the most common refractive surgery and has been performed for over 20 years.[1] As patients with LASIK age, they inevitably develop cataracts and need surgery. However, intraocular lens (IOL) power calculations after refractive surgery are challenging.[2] Even with historical data and various post-LASIK IOL calculation methods, postoperative refractive surprises can still occur due to alteration of the natural corneal curvature.[2-7]
Monofocal lenses can offer great refractive results in patients with no previous keratorefractive surgeries, and most patients achieve excellent uncorrected distance visual acuity (UCDVA) with predictable results. In contrast, multifocal IOLs (MFIOLs) are sensitive to corneal irregularities, and therefore, most surgeons are hesitant to place MFIOL in patients with previous keratorefractive surgery. In general, MFIOLs offer a greater range of vision compared to a monofocal lens,[8-10] to achieve greater spectacle independence for distance, intermediate, and near vision.[9,10] Intriguingly, studies have shown that MFIOL can achieve good results for UCDVA, intermediate, and near vision even in patients with previous LASIK[2,11-16] and other refractive surgeries.[1,17] However, in post-LASIK patients, one potential disadvantage of MFIOLs is that they might exacerbate the undesirable postoperative symptoms related to optical aberrations, including glare and halos.[18-20]
The few studies that have examined MFIOL in post-keratorefractive patients report that satisfactory outcomes are possible. However, recommendations for IOL options appear limited to studies related to eyes without refractive surgery. Studies comparing final visual outcome and tolerance of residual refractive errors of MFIOL and monofocal lenses in post-keratorefractive patients are limited.[16,21] In this paper, we present a retrospective comparative study of post-LASIK patients who underwent cataract surgery and received either diffractive MFIOL or monofocal lens, to provide the cataract surgeon an evidence-based lens decision after keratorefractive surgery. The diffractive MFIOL has an anterior diffractive aspheric surface with a central diffractive zone and has an addition of diopters. Certain class of MFIOL in this study is also designed to eliminate spherical aberration in the IOLs, leaving the corneal spherical aberration to introduce extended depth of focus. We proposed that the diffractive MFIOL with extended depth of focus may compensate for residual uncorrected refractive error and may not be inferior to or may have highly acceptable tolerance for residual refractive error compared to the monofocal lens in patients with previous LASIK.
Methods
This was a single-center, retrospective, comparative study. Written informed consent was obtained in advance from all patients in accordance with the principles expressed in the Declaration of Helsinki for human subjects. All subjects had a history of myopic or hyperopic LASIK and underwent femtosecond laser-assisted cataract surgery (FLACS) in one or both eyes with either a diffractive MFIOL or monofocal lens. Consent was obtained from the study participants before study commencement. All surgeries were performed by a single surgeon (KAW). Monofocal lenses implanted were either TECNIS® Monofocal 1-Piece Model ZCB00 or the preloaded system TECNIS iTEC® PRELOADED IOL Model PCB00 (Johnson & Johnson Surgical Vision, Inc.). Two different classes of diffractive MFIOL were used and grouped together. The first class included TECNIS multifocal model ZLBOO, ZKBOO, and ZMBOO (Johnson & Johnson Surgical Vision, Inc.) and the second class included TECNIS Symfony IOL (Johnson & Johnson Surgical Vision, Inc.). Inclusion criterion for the study was patients undergoing uncomplicated cataract surgeries. Other ocular comorbidities were excluded before performing cataract surgeries, such as glaucoma, diabetic maculopathy, macular degeneration, corneal transplants, and retinal surgeries or any other pathologies that can potentially compromise visual acuity. The choice of the IOL with cost and postoperative expectations in each lens category was provided. All patients were counseled about the potential of using spectacles for both distance and near with monofocal lens. In contrast, potential broader range of vision and possible lesser degree of spectacle dependency glare, but the possibility of halo or loss of contrast in dim light settings on usage of MFIOL lens were emphasized to patients. We provided adequate counseling regarding the possibility of a loss of contrast and temporary nighttime dysphotopsia in exchange for a broader range of vision postoperatively. Furthermore, all patients were counseled about the potential hyperopic and myopic surprises due to previous keratorefractive surgeries. Written informed consents were obtained, and all were documented in the medical record before surgery. All astigmatic corrections were performed with a femtosecond laser, and corrections were suggested by LRIcalculator.com. The IOL power was selected by choosing the negative spherical equivalent (SE) closest to zero. The suggested corrections were reduced by 20% to account for a smaller optical zone.
Demographic data and preoperative data including best corrected distance visual acuity (BCDVA) with glare and preoperative topography were recorded and are summarized in Table 1. Postoperative data such as uncorrected distance visual acuity (UCDVA), residual refractive errors and spectacle dependency were compared. All lens power calculations were performed with a Barrett True-K calculator provided by the Asia-Pacific Association of Cataract and Refractive Surgery (APACRS) (www.apacrs.org). Higher-order aberrations (HOAs) and intraoperative aberrometry were not measured. Patients were followed up on postoperative day 1, week 1, followed by 1 month, 6 months, and thereafter.
Table 1.
Summary of relevant preoperative clinical data of patients
| Multifocal | Monofocal | P | |
|---|---|---|---|
| n (patients/eyes) | 51/93 | 50/82 | 0.67 |
| Age (years) | 66.22±6.84 | 68.82±7.91 | 0.084 |
| Female/male (n) | 28/23 | 28/22 | 0.91 |
| Myopia/hyperopia LASIK (no. of eyes) | 71/22 | 66/16 | 0.52 |
| Preoperative BCVA with glare logMAR | 0.54±0.32 | 0.56±0.33 | 0.76 |
| Preoperative refraction (SE) | -0.37±1.53 | -0.84±1.58 | 0.6 |
| Preoperative average K (D) | 41.73±2.52 | 41.79±2.492 | 0.86 |
| Type of cataract (n) | 0.92 | ||
| Nuclear sclerosis | 52 | 47 | |
| Cortical opacity | 13 | 12 | |
| Posterior subcapsular cataract | 3 | 2 | |
| Combination | 25 | 21 |
BCVA=best corrected visual acuity, K=keratometry, LASIK=laser-assisted in situ keratomileusis, logMAR=logarithm of the minimum angle of resolution, SE=spherical equivalent
The comparative statistical analyses were carried out using Statistical Package for the Social Sciences (SPSS) software version 20.0 (IBM, Armonk, NY, USA). Continuous data were reported as mean ± standard deviation or median and range, and categorical data were described using frequency and percentage. Fisher exact test and t-test were used to compare categorical data and continuous data, respectively. A P value less than 0.05 was considered statistically significant.
Results
A total of 175 eyes and 101 patients were included in the analysis. There were 50 patients (82 eyes) in the LASIK monofocal group and 51 patients (93 eyes) in the LASIK diffractive MFIOL group. Cataracts were categorized as 56% (52/93) versus 57% (47/82) of nuclear sclerosis, 14% (13/93) versus 15% (12/82) of cortical opacity, 3% (3/93) versus 2.4% (2/82) of posterior subcapsular cataract, and 27% (25/93) versus 26% (21/82) of combination in MFIOL and monofocal groups, respectively. Preoperative data and patient demographic are summarized in Table 1. There was no statistical difference found in any demographic characteristic between the two groups. Mean follow-up periods were not different in mono and diffractive groups (10.8 ± 6.2 vs. 11.2 ± 4.1 months, P = 0.8).
The final vision in the post-LASIK MFIOL group showed better UCDVA compared to the monofocal group (logarithm of the minimum angle of resolution [logMAR] 0.054 ± 0.092 vs. 0.203 ± 0.218, P = 1.0 x 10−5) [Fig. 1]. More patients with MFIOL lenses achieved UCDVA of 20/25 or better compared to the monofocal lens group (80 of 93 eyes, 86% vs. 36 of 82 eyes, 43.9%, P = 1.0 x 10−5) [Fig. 2]. All patients in the study were able to achieve BCDVA of 20/20. The BCDVA was not statistically significantly different between the two groups (P = 0.1).
Figure 1.
Comparison of UCDVA in logMAR between eyes with diffractive multifocal and monofocal intraocular lenses. The post-LASIK multifocal group showed better UCDVA compared to the monofocal group (logMAR 0.054 ± 0.092 vs. 0.203 ± 0.218). ***Significance value P < 1.0 x 10−5. LASIK = laser-assisted in situ keratomileusis, logMAR = logMAR = logarithm of the minimum angle of resolution, UCDVA = uncorrected distance visual acuity
Figure 2.
Comparison of overall percentage of eyes that achieved UCDVA of 20/25 or better between eyes with diffractive multifocal and monofocal intraocular lenses. More patients with multifocal lenses achieved UCDVA of 20/25 or better compared to the monofocal lens group (80 of 93 eyes, 86% vs. 36 of 82 eyes, 43.9%). ***Significance value P < 1.0 x 10−5. UCDVA = uncorrected distance visual acuity
Patients with MFIOL placements (n = 93) and monofocal lens (n = 63) had post-cataract refractive error measurement [summarized in Table 2]. The absolute residual SE of patients with MFIOL (0.37 ± 0.39) had no significant difference (P = 0.16) compared to that of patients with monofocal lens (0.44 ± 0.39). In addition, more patients in the MFIOL group obtained final residual SE within ±0.50 D (72 eyes, 77.4% vs. 41 eyes, 65%, P = 0.065) but did not reach statistically significant difference compared to the monofocal group. For residual SE ranging from 0.25 to 0.5 D, more eyes in the MFIOL group achieved UCDVA of 20/25 or better (36 of 42 eyes, 86%) compared to 15 of 24 eyes (63%; P = 0.032) in the monofocal group. Similarly, for residual SE larger than 0.75 D, more eyes in the MFIOL group achieved UCDVA of 20/25 or better (15 of 21 eyes, 23% vs. 0 of 22 eyes, 0%, P = 1.0 x 10−5).
Table 2.
Change in refractive error in the diffractive multifocal and monofocal groups
| Multifocal | Monofocal | P | |
|---|---|---|---|
| Number of eyes | 93 | 63 | 0.1 |
| Pre-op refractive error (D) | −0.37±1.53 | −0.84±1.58 | 0.6 |
| Absolute post-op refractive error (D) | 0.37±0.39 | 0.44±0.39 | 0.16 |
| Post-op refractive error 0 D (n) | 30 | 17 | 0.2 |
| Post-op refractive error 0.25-0.5 D (n) | 42 | 24 | 0.383 |
| Post-op refractive error 0.25-0.5 D and UCDVA 20/25 or better (n) | 36 | 15 | 0.032 |
| Postop refractive error >0.75 D (n) | 21 | 22 | 0.9 |
| Postop refractive error >0.75 D and UCDVA 20/25 or better (n) | 15 | 0 | <0.001 |
UCDVA=uncorrected distance visual acuity
In the MFIOL group, 72 of 93 eyes (77%) required no additional reading spectacles. Fifteen eyes achieved J1+, 44 eyes achieved J1, and 13 eyes achieved J2 for their near vision and required no additional spectacles for their near vision tasks.
In contrast, all patients in the monofocal group required reading spectacles for their near tasks (82 eyes, 100%; P = 1.0 x 10−5). Refractive lens exchange due to decrease in contrast or glare and halo was not performed in both groups.
Discussion
This study suggests that patients with a history of LASIK who undergo cataract surgery with a diffractive MFIOL are more likely to achieve not only excellent near vision but also better UCDVA regardless of the residual SE, compared to patients receiving monofocal lens. In patients without history of refractive surgery, MFIOL showed an excellent mean UCDVA ranging from −0.01 to 0.08 logMAR (Snellen equivalent, 20/20–20/24) (summarized in[22,23]). While some studies have reported good UCDVA in MFIOL implantation after keratorefractive laser surgery,[11-16,20,24,25] only limited reports compare the visual results of MFIOL and monofocal lens in eyes with previous refractive surgery.[16,21] To our knowledge, our study of post-LASIK–implanted 82 eyes with monofocal lens and 93 eyes with diffractive MFIOL is the largest reported.
In a retrospective study[16] of post-LASIK with 21 eyes with monofocal lens and 23 eyes with MFIOL, more eyes in the MFIOL group showed UCDVA of 20/25 (79% vs. 68%) or 20/20 or better (42% vs. 29%) compared to eyes in the monofocal lens group, although no statistically significant difference was reached. Notably, only 18 eyes were included in the monofocal group, where the refractive target was plano. The study also reported that more eyes in the MFIOL group had a residual refraction within 0.50 D (P = 0.03). Similarly, in a prospective Portugal study[21] of total 88 eyes, with 44 eyes in each IOL group, more eyes in the MFIOL group achieved binocular UCDVA of 20/20 or better (100% vs. 93%) compared to the monofocal group, although there was no significant difference between groups. For residual SE, there was no significant difference between the monofocal group and MFIOL group within ±0.50 D (56.8% vs. 54.5%) and ±1.00 D (86.4% vs. 81.8%). Our finding differs in that our MFIOL group showed significantly better UCDVA regardless of the residual SE. A large review study of MFIOL visual outcomes showed that UCDVA was better than 20/25 in 73.7% of diffractive MFIOL group after surgery (summarized in[26]). In our study, one of the lenses used in MFIOL had a wavefront-designed anterior aspheric surface with posterior achromatic diffractive surface and a proprietary echelette design, resulting in an elongated depth of focus. The rest of the MFIOLs used achieved multifocality with aspheric anterior surface and a posterior surface with diffractive rings that focused both near and distance light.[9] In addition, our results correlated with myopic, astigmatic, and absolute hypermetropic eyes.[9,27] We believe that our finding is further strengthened by the larger sample size of the study.
Recent studies have shown that residual SE or astigmatism can significantly decrease visual acuity from induced optical defocus.[27,28] In monofocal lens, any minor residual SE deviation from plano will result in UCDVA worse than 20/20.[26,27] Interestingly, in our MFIOL group, a significant number of patients with residual SE were still able to achieve UCDVA of 20/25 or better. A French study[29] observed that the (EDOF) extended depth of focus MFIOL demonstrated an excellent tolerance to residual SE in 386 eyes. Specifically the postoperative binocular UCDVA had a minimal reduction of visual acuity from 20/20 to 20/21 despite high residual SE of ±2.00D and astigmatism up to 0.75D. The study showed that residual SE had a minimal and clinically insignificant impact on UCDVA after placement of EDOF lens in patients without previous refractive surgery. Several other studies have similarly reported significantly better refractive tolerance in eyes with EDOF lens compared to monofocal lens, including a prospective study[30] with 60 eyes of EDOF lens and 60 eyes of monofocal lens and another prospective study[31] that included 50 eyes of EDOF lens and 30 eyes of monofocal lens. Moreover, all the EDOF subgroups with postoperative residual SE (within ±0.5 D, within −1 D, more than −1 D) had significantly better mean UCDVA than the monofocal subgroups.[30] Further, the study showed that the EDOF lens had fewer visual disturbances to provide excellent visual acuity at all distances when compared to not only monofocal but also standard MFIOLs. A prospective study identified that the UCDVA was significantly better in the 55 patients with EDOF lens than it was in the 30 patients with monofocal lens or 100 patients with non-EDOF MFIOL.[32] Our results reaffirmed the notion that diffractive MFIOL is well tolerated even in patients with prior keratorefractive surgery despite having residual refractive error.
Determining an accurate IOL power for patients with previous keratorefractive surgery can be challenging, often leading to unpredictable results.[1] Various formulas have been used for patients with previous keratorefractive surgeries to improve postoperative predictability.[1,4-6] In our study of post-LASIK patients, we used the Barrett True-K Formula through the American Society of Cataract and Refractive Surgery (ASCRS) website and IOL power was selected by choosing the negative SE closest to zero. The Barrett True-K formula has been shown to be equal to or better than the alternative methods available on the ASCRS website for predicting IOL power in eyes with previous LASIK or Photorefractive keratectomy (PRK).[5] In addition, we further showed that our patients with diffractive MFIOL had very good near vision in post-LASIK cataract surgery, a finding that is comparable to previous studies.[11-16,20,21,24,25] The promising results may be attributed to diffractive design or continuous power change of the MFIOL. As the population of post-refractive surgery patients ages, they will have higher expectations of achieving spectacle independence. The EDOF technology may offer a greater range of clear vision and an overall higher probability of achieving 20/25 or better UCDVA in patients with previous keratorefractive surgeries. Furthermore, our study synergistically combines MFIOLs with FLACS to provide a level of precision that enables nomogram adjustment and systematic improvements.[33]
While the results from this study support the option of implantation of an MFIOL after previous keratorefractive surgery, there are several limitations. All the MFIOLs implanted in our post- LASIK patients were confined to a single manufacturer and only to diffractive MFIOLs including TECNIS Symfony IOL, TECNIS multifocal, and TECNIS symfony toric IOL. Despite the fact that diffractive MFIOL may improve intermediate vision significantly but near vision only modestly compared to other standard MFIOLs, our data have shown promising results of near vision after placement of diffractive MFIOL in patients with previous LASIK. Future prospective comparative studies can include other types of MFIOLs, such as refractive and accommodative lenses, to verify our results. In addition, although all operations were performed by the same surgeon (KAW) to eliminate inter-rater variability, refraction was not performed by a single technician. Further study designed with a single technician would provide more robust measurements. Finally, this is a retrospective study and we focused mainly on postoperative visual acuity; other visual parameters such as pupil size, contrast sensitivity, glare, haloes, intermediate distance vision, HOA, aberration, and quality of vision of the patients were not evaluated. Even with perfect visual acuity, the presence of increased HOAs, glare, or haloes may impact visual performance negatively after MFIOL implantation. This pilot study suggests that patients with a history of LASIK who undergo cataract surgery with a diffractive multifocal lens are not inferior to those who receive monofocal lens and may achieve potentially better UCDVA. Although there was no refractive lens exchange for decrease in contrast or glare and halo for both groups, further potential prospective study would be needed to determine the pre- and post-changes in contrast sensitivity, aberration, and quality of vision of the patients. A large prospective study with more comprehensive inclusion criteria can help confirm our findings that MFIOL is a good option for patients with a history of LASIK who undergo cataract surgery.
Conclusion
This pilot study shows that patients with a history of LASIK who undergo cataract surgery with a diffractive multifocal lens are not inferior to those who receive monofocal lenses. Additionally, post-LASIK patients with diffractive lenses are more likely to achieve not only excellent near vision, but also potentially better UCDVA despite having significant residual refractive error. Finally, our findings suggest that diffractive multifocal lenses are well tolerated in post keratorefractive patients despite having residual refractive error.
Financial support and sponsorship
Dr. Keith Walter is a consultant for Johnson & Johnson.
Conflicts of interest
There are no conflicts of interest.
References
- 1.Solomon KD, Fernández de Castro LE, Sandoval HP, Biber JM, Groat B, Neff KD, et al. LASIK world literature review:Quality of life and patient satisfaction. Ophthalmology. 2009;116:691–701. doi: 10.1016/j.ophtha.2008.12.037. [DOI] [PubMed] [Google Scholar]
- 2.McCarthy M, Gavanski GM, Paton KE, Holland SP. Intraocular lens power calculations after myopic laser refractive surgery:A comparison of methods in 173 eyes. Ophthalmology. 2011;118:940–4. doi: 10.1016/j.ophtha.2010.08.048. [DOI] [PubMed] [Google Scholar]
- 3.Wang L, Hill WE, Koch DD. Evaluation of intraocular lens power prediction methods using the American Society of Cataract and Refractive Surgeons Post-Keratorefractive Intraocular Lens Power Calculator. J Cataract Refract Surg. 2010;36:1466–73. doi: 10.1016/j.jcrs.2010.03.044. [DOI] [PubMed] [Google Scholar]
- 4.Wang L, Tang M, Huang D, Weikert MP, Koch DD. Comparison of newer intraocular lens power calculation methods for eyes after corneal refractive surgery. Ophthalmology. 2015;122:2443–9. doi: 10.1016/j.ophtha.2015.08.037. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Abulafia A, Hill WE, Koch DD, Wang L, Barrett GD. Accuracy of the Barrett True-K formula for intraocular lens power prediction after laser in situ keratomileusis or photorefractive keratectomy for myopia. J Cataract Refract Surg. 2016;42:363–9. doi: 10.1016/j.jcrs.2015.11.039. [DOI] [PubMed] [Google Scholar]
- 6.Savini G, Hoffer KJ. Intraocular lens power calculation in eyes with previous corneal refractive surgery. Eye Vis (Lond) 2018;5:18. doi: 10.1186/s40662-018-0110-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 7.Walter KA, Gagnon MR, Hoopes PC, Jr, Dickinson PJ. Accurate intraocular lens power calculation after myopic laser in situ keratomileusis, bypassing corneal power. J Cataract Refract Surg. 2006;32:425–9. doi: 10.1016/j.jcrs.2005.12.140. [DOI] [PubMed] [Google Scholar]
- 8.Hayashi K, Ogawa S, Manabe S, Hirata A. Visual outcomes in eyes with a distance-dominant diffractive multifocal intraocular lens with low near addition power. Br J Ophthalmol. 2015;99:1466–70. doi: 10.1136/bjophthalmol-2014-306476. [DOI] [PubMed] [Google Scholar]
- 9.Alio J, Plaza-Puche A, Férnandez-Buenaga R, Pikkel J, Maldonado M. Multifocal intraocular lenses:An overview. Surv Ophthalmol. 2017;62:611–34. doi: 10.1016/j.survophthal.2017.03.005. [DOI] [PubMed] [Google Scholar]
- 10.Zvorničanin J, Zvorničanin E. Premium intraocular lenses:The past, present and future. J Curr Ophthalmol. 2018;30:287–96. doi: 10.1016/j.joco.2018.04.003. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 11.Alfonso JF, Madrid-Costa D, Poo-López A, Montés-Micó R. Visual quality after diffractive intraocular lens implantation in eyes with previous myopic laser in situ keratomileusis. J Cataract Refract Surg. 2008;34:1848–54. doi: 10.1016/j.jcrs.2008.07.023. [DOI] [PubMed] [Google Scholar]
- 12.Fernández-Vega L, Madrid-Costa D, Alfonso JF, Montés-Micó R, Poo-López A. Optical and visual performance of diffractive intraocular lens implantation after myopic laser in situ keratomileusis. J Cataract Refract Surg. 2009;35:825–32. doi: 10.1016/j.jcrs.2008.12.040. [DOI] [PubMed] [Google Scholar]
- 13.Alfonso JF, Fernández-Vega L, Baamonde B, Madrid-Costa D, Montés-Micó R. Refractive lens exchange with spherical diffractive intraocular lens implantation after hyperopic laser in situ keratomileusis. J Cataract Refract Surg. 2009;35:1744–50. doi: 10.1016/j.jcrs.2009.04.045. [DOI] [PubMed] [Google Scholar]
- 14.Muftuoglu O, Dao L, Mootha VV, Verity SM, Bowman RW, Cavanagh HD, et al. Apodized diffractive intraocular lens implantation after laser in situ keratomileusis with or without subsequent excimer laser enhancement. J Cataract Refract Surg. 2010;36:1815–21. doi: 10.1016/j.jcrs.2010.05.021. [DOI] [PubMed] [Google Scholar]
- 15.Alfonso JF, Fernández-Vega L, Baamonde B, Madrid-Costa D, Montés-Micó R. Visual quality after diffractive intraocular lens implantation in eyes with previous hyperopic laser in situ keratomileusis. J Cataract Refract Surg. 2011;37:1090–6. doi: 10.1016/j.jcrs.2010.11.043. [DOI] [PubMed] [Google Scholar]
- 16.Fisher B, Potvin R. Clinical outcomes with distance-dominant multifocal and monofocal intraocular lenses in post-LASIK cataract surgery planned using an intraoperative aberrometer. Clin Exp Ophthalmol. 2018;46:630–6. doi: 10.1111/ceo.13153. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Christopher KL, Miller DC, Patnaik JL, Lynch AM, Davidson RS, Taravella MJ. Comparison of visual outcomes of extended depth of focus lenses in patients with and without previous laser refractive surgery. J Refract Surg. 2020;36:28–33. doi: 10.3928/1081597X-20191204-01. [DOI] [PubMed] [Google Scholar]
- 18.Chang JS, Ng JC, Lau SY. Visual outcomes and patient satisfaction after presbyopic lens exchange with a diffractive multifocal intraocular lens. J Refract Surg. 2012;28:468–74. doi: 10.3928/1081597X-20120612-01. [DOI] [PubMed] [Google Scholar]
- 19.Chang JS, Ng JC, Chan VK, Law AK. Visual outcomes and patient satisfaction after refractive lens exchange with a single-piece diffractive multifocal intraocular lens. J Ophthalmol. 2014;2014:458296. doi: 10.1155/2014/458296. doi:10.1155/2014/458296. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Chang JS, Ng JC, Chan VK, Law AK. Visual outcomes, quality of vision, and quality of life of diffractive multifocal intraocular lens implantation after myopic laser in situ keratomileusis:A prospective, observational case series. J Ophthalmol. 2017;2017:6459504. doi: 10.1155/2017/6459504. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Ferreira TB, Pinheiro J, Zabala L, Ribeiro FJ. Comparative analysis of clinicalBoutcomes of a monofocal and an extended-range-of-vision intraocular lens in eyes with previous myopic laser in situ keratomileusis. J Cataract Refract Surg. 2018;44:149–55. doi: 10.1016/j.jcrs.2017.11.007. [DOI] [PubMed] [Google Scholar]
- 22.Schallhorn JM, Pantanelli SM, Lin CC, Al-Mohtaseb ZN, Steigleman WA, 3rd, Santhiago MR, et al. Multifocal and Accommodating Intraocular Lenses for the Treatment of Presbyopia:A report by the American Academy of Ophthalmology. Ophthalmology. 2021;128:1469–82. doi: 10.1016/j.ophtha.2021.03.013. [DOI] [PubMed] [Google Scholar]
- 23.Rosen E, Alió JL, Dick HB, Dell S, Slade S. Efficacy and safety of multifocal intraocular lenses following cataract and refractive lens exchange:Metaanalysis of peer-reviewed publications. J Cataract Refract Surg. 2016;42:310–28. doi: 10.1016/j.jcrs.2016.01.014. [DOI] [PubMed] [Google Scholar]
- 24.Vrijman V, van der Linden JW, van der Meulen IJE, Mourits MP, Lapid-Gortzak R. Multifocal intraocular lens implantation after previous corneal refractive laser surgery for myopia. J Cataract Refract Surg. 2017;43:909–14. doi: 10.1016/j.jcrs.2017.06.028. [DOI] [PubMed] [Google Scholar]
- 25.Vrijman V, van der Linden JW, van der Meulen IJE, Mourits MP, Lapid-Gortzak R. Multifocal intraocular lens implantation after previous hyperopic corneal refractive laser surgery. J Cataract Refract Surg. 2018;44:466–70. doi: 10.1016/j.jcrs.2018.01.030. [DOI] [PubMed] [Google Scholar]
- 26.Alio JL, Plaza-Puche AB, Férnandez-Buenaga R, Pikkel J, Maldonado M. Multifocal intraocular lenses:An overview. Surv Ophthalmol. 2017;62:611–34. doi: 10.1016/j.survophthal.2017.03.005. [DOI] [PubMed] [Google Scholar]
- 27.Raasch TW. Spherocylindrical refractive errors and visual acuity. Optom Vis Sci. 1995;72:272–5. doi: 10.1097/00006324-199504000-00008. [DOI] [PubMed] [Google Scholar]
- 28.Moon BY, Kim SY, Cho HG. Predicting of uncorrected astigmatism from decimal visual acuity in spherical equivalent. J Opt Soc Korea. 2013;17:219–3. [Google Scholar]
- 29.Cochener B. Tecnis symfony intraocular lens with a “sweet spot”for tolerance to postoperative residual refractive errors. Open J Ophthalmol. 2017;7:14–20. [Google Scholar]
- 30.Son HS, Kim SH, Auffarth GU, Choi CY. Prospective comparative study of tolerance to refractive errors after implantation of extended depth of focus and monofocal intraocular lenses with identical aspheric platform in Korean population. BMC Ophthalmol. 2019;19:187. doi: 10.1186/s12886-019-1193-z. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 31.Pedrotti E, Bruni E, Bonacci E, Badalamenti R, Mastropasqua R, Marchini G. Comparative analysis of the clinical outcomes with a monofocal and an extended range of vision intraocular lens. J Refract Surg. 2016;32:436–42. doi: 10.3928/1081597X-20160428-06. [DOI] [PubMed] [Google Scholar]
- 32.Pedrotti E, Carones F, Aiello F, Mastropasqua R, Bruni E, Bonacci E, et al. Comparative analysis of visual outcomes with 4 intraocular lenses:Monofocal, multifocal, and extended range of vision. J Cataract Refract Surg. 2018;44:156–67. doi: 10.1016/j.jcrs.2017.11.011. [DOI] [PubMed] [Google Scholar]
- 33.Barnett BP. FOCUSED (Femtosecond Optimized Continuous Uncorrected Sight with EDOF and Diffractive Multifocal IOLs)-A review. Curr Opin Ophthalmol. 2021;32:3–12. doi: 10.1097/ICU.0000000000000723. [DOI] [PubMed] [Google Scholar]