Diffractive Multifocal Intraocular Lens Research Articles

Visual Performance after Bilateral Implantation of a Four-Haptic Diffractive Toric Multifocal Intraocular Lens in High Myopes.

Background. The vision with diffractive toric multifocal intraocular lenses after cataract surgery in long eyes has not been studied previously. Objectives. To report visual performance after bilateral implantation of a diffractive toric multifocal intraocular lens in high myopes. Methods. Prospective, observational case series to include patients with axial length of ≥26 mm and corneal astigmatism of >1 dioptre who underwent bilateral AT LISA 909M implantation. Postoperative examinations included photopic and mesopic distance, intermediate, and near visual acuity; photopic contrast sensitivity; visual symptoms (0–5); satisfaction (1–5); and spectacle independence rate. Results. Twenty-eight eyes (14 patients) were included. Postoperatively, mean photopic monocular uncorrected distance, intermediate, and near visual acuities (logMAR) were 0.12 ± 0.20 (standard deviation), 0.24 ± 0.16, and 0.29 ± 0.21, respectively. Corresponding binocular values were −0.01 ± 0.14, 0.13 ± 0.12, and 0.20 ± 0.19, respectively. One eye (4%) had one-line loss in vision. Under mesopic condition, intermediate vision and near vision decreased significantly (all P ≤ 0.001). Contrast sensitivity at all spatial frequencies did not improve significantly under binocular condition (all P > 0.05). Median scores for halos, night glare, starbursts, and satisfaction were 0.50, 0.00, 0.00, and 4.25, respectively. Ten patients (71%) reported complete spectacle independence. Conclusions. Bilateral implantation of the intraocular lens in high myopes appeared to be safe and achieved good visual performance and high satisfaction.

Effect of Previous Myopic Laser In Situ Keratomileusis on Contrast Sensitivity After Diffractive Multifocal Intraocular Lens Implantations

Objective: To evaluate effects of previous myopic laser in-situ keratomileusis (LASIK) on decrease in contrast sensitivity after implantation of diffractive multifocal intraocular lens (MF-IOL). Methods: Retrospective case series included eyes that were implanted diffractive MF-IOLs after myopic LASIK. Contrast sensitivity was measured 1 month postoperatively and the area under log contrast sensitivity (AULCSF) was calculated. Principle component analysis (PCA) was used for extracting principal factors related with the previous LASIK and MF-IOL implantation. Effects of decrease in postoperative AULCSF and contrast sensitivity at each spatial frequency were evaluated using step-wise multiple regression analysis. Results: Twenty-six eyes of 20 patients were included. The mean postoperative uncorrected distance visual acuity was -0.06 ± 0.13 logMAR (20/17 in Snellen) and all eyes achieved 20/20 or better. The PCA determined central corneal thickness (CCT), distance-corrected near visual acuity, and absolute manifest refraction as principal factors. The multiple regression analysis revealed that the AULCSF showed significant decrease with a thinner CCT (P=0.017), while a particular trend was not found in the analysis results at the spatial frequencies. Conclusion: Degradation in contrast sensitivity after implantation of MF-IOLs in post-LASIK eyes was more affected by the amount of the previous LASIK corrections.

Long-Term Stability of Diffractive Multifocal Intraocular Lenses: Contralateral Comparison between Silicone and Acrylic Materials

Objective: To compare visual function stability between silicone and hydrophobic acrylic materials of diffractive multifocal intraocular lenses (MF-IOLs). Methods: This retrospective study reviewed clinical records of 10 patients who received a silicone MF-IOL in the first eye and hydrophobic acrylic lens in the fellow eye. Intra-individual differences in logMAR corrected distance visual acuity (CDVA) and distance-corrected near visual acuity (DCNVA) were evaluated until 2 years postoperatively. Contrast sensitivity at 1 year was also compared. Results: Age of the patients ranged from 39 to 77 years. There was no statistical difference in the uncorrected distance visual acuities at 2 years, while the uncorrected near visual acuity of the silicone IOL was better (P=0.046). The medians of the CDVA and DCNVA with the silicone MF-IOLs were -0.13 and 0.10 logMAR, respectively, while those with hydrophobic acrylic MF-IOLs were -0.09 and 0.12 logMAR, respectively. No significant difference was found between the two materials (P>0.17). There was no difference in the contrast sensitivity (P>0.11). One eye with the silicone MF-IOL underwent Nd:YAG laser capsulotomy. Conclusions: The differences in the material and fabrication of diffractive MF-IOLs did not influence the longterm visual performance.

Safety and efficacy of two multifocal intraocular lenses in the treatment of senile cataract: study protocol for a randomized controlled trial

Background: Phacoemulsification with intraocular lens (IOL) implantation has become a well-established treatment for senile cataract. The ideal IOL is characterized by good biocompatibility and resolution, with no spherical aberration. The Acri.LISA 366D is a refractive/diffractive multifocal IOL that differs from traditional multifocal IOLs. Its unique optical design can improve the patient's vision and reduce incident ray scattering, glare and halo. The goal of this study is to perform a comparative analysis between the Acri.LISA 366D and the Tecnis Z9001 diffractive multifocal IOL, to determine if there are any differences in biocompatibility and improvement in visual acuity. Methods/Design: A prospective, single-center, randomized, double-blind, parallel-controlled study will be conducted at the Affiliated Hospital of Qinghai University in China. Forty cataract patients aged 50-80 years will be randomly assigned to either the Acri.LISA 366D or Tecnis Z9001 IOL (n = 20 per group). The primary outcome of the trial is to investigate the biocompatibility of the IOL after implantation. The secondary outcome is the best corrected visual acuity. Outcome measures will be evaluated at 1, 3, 6 months, 1, 2 years after IOL implantation. Discussion: It is anticipated that the data collected from this trial will provide evidence for IOL selection in senile cataract patients. Trial registration: ClinicalTrials.gov identifier: NCT02966496; registered on 9 November 2016. Ethics: This trial has been approved by the Ethics Committee, Affiliated Hospital of Qinghai University, China (approval number: QHY1107K) and will be performed in accordance with the Declaration of Helsinki, formulated by the World Medical Association. Informed consent: Signed informed consent will be obtained from the patients or their guardians.

Visible Versus Near-Infrared Optical Performance of Diffractive Multifocal Intraocular Lenses.

The purpose of this study was to compare the optical performance of diffractive multifocal intraocular lenses (DMIOLs) with visible (VIS) illumination with that of near infrared (NIR) illumination, the latter being used to test pseudophakic eyes in clinical aberrometers and double-pass systems. Two DMIOLs of different design (Tecnis +2.75 D ZKB00 and AcrySof +2.5 D SV25T0) were tested in vitro in a model eye under both VIS (λ = 530 nm) and NIR (λ = 780 nm) illumination, and variations in the add power of the lenses were determined. Moreover, for the two wavelengths, the energy efficiency and modulation transfer function at the DMIOLs' far and near foci were measured with pupils of 3.0 and 4.5 mm. Two counterpart monofocal IOLs (Tecnis ZA9003 and AcrySof SN60WF) were included as references in the comparison. With VIS light, the two DMIOLs produced relatively well-contrasted images at their near and far foci. Under NIR illumination, the add power increased, whereas the energy efficiency of the near focus decreased and that of far focus increased. Hence, the DMIOLs tended to behave like monofocal lenses because they generated good quality well-contrasted images only at their far foci. In addition to changes in add power, the optical performances of the DMIOLs measured under either VIS or NIR illumination are considerably different. Whereas they show two distinct (near and far) foci under VIS light, their optical performances under NIR illumination are clearly biased in favor of their far focus. These results may help prevent a misleading use of NIR-based clinical instruments for the assessment of eyes implanted with DMIOLs.

Disk halo size measured in individuals with monofocal versus diffractive multifocal intraocular lenses

To compare disk halo size in response to a glare source in eyes with an aspheric apodized diffractive multifocal intraocular lens (IOL) or aspheric monofocal IOL. Rementeria Ophthalmological Clinic, Madrid, Spain. Prospective randomized masked study. Halo radius was measured using a vision monitor (MonCv3) with low-luminance optotypes in eyes that had cataract surgery and bilateral implantion of an Acrysof Restor SN6AD1 multifocal IOL or Acrysof IQ monofocal IOL 6 to 9 months previously. The visual angle subtended by the disk halo radius was calculated in minutes of arc (arcmin). Patient complaints of halo disturbances were recorded. Monocular uncorrected distance visual acutity (UDVA) and corrected distance visual acuity (CDVA) were measured using high-contrast (96%) and low-contrast (10%) logMAR letter charts. The study comprised 39 eyes of 39 subjects (aged 70 to 80 years); 21 eyes had a multifocal IOL and 18 eyes a monofocal IOL. The mean halo radius was 35 arcmin larger in the multifocal IOL group than the monofocal group (P < .05). Greater halo effects were reported in the multifocal IOL group (P < .05). The mean monocular high-contrast UDVA and low-contrast UDVA did not vary significantly between groups, whereas the mean monocular high-contrast CDVA and low-contrast CDVA were significantly worse at 0.12 logMAR and 0.13 logMAR in the multifocal than in the monofocal IOL group, respectively (P < .01). A significant positive correlation was detected by multiple linear regression between the halo radius and low-contrast UDVA in the multifocal IOL group (r = 0.72, P < .001). The diffractive multifocal IOL gave rise to a larger disk halo size, which was correlated with a worse low-contrast UDVA. None of the authors has a financial or proprietary interest in any material or method mentioned.

Primary posterior continuous curvilinear capsulorhexis combined with diffractive multifocal intraocular lens implantation.

PurposeTo evaluate the effect of mild posterior capsule opacity (PCO) on visual acuity (VA) in eyes implanted with a diffractive multifocal intraocular lens (IOL) compared with a monofocal IOL, and the effect of posterior continuous curvilinear capsulorhexis (PCCC) combined with diffractive multifocal IOL implantation.MethodsFor the initial evaluation, we compared charge-coupled device (CCD) camera photographs taken through both a monofocal IOL-loaded model eye and a diffractive IOL-loaded model eye under the conditions of both with and without an opaque filter for the simulation of mild PCO. The clinical evaluation involved 20 patients who underwent bilateral implantation of the same diffractive multifocal IOL. In all 20 cases, PCCC was performed in 1 eye (PCCC group) and not performed in the fellow eye (NCCC group). Postoperative clinical results were then compared between the two groups.ResultsThe CCD photographs revealed that the diffractive IOL-loaded eye was more strongly affected by the simulated PCO than was the monofocal IOL-loaded eye. In the clinical setting, the PCCC group registered better results than NCCC group in distance and near VA, low-contrast VA, and contrast sensitivity testing.ConclusionsDiffractive multifocal IOLs tend to be more influenced by mild PCO than do monofocal IOLs, and PCCC prior to IOL implantation can contribute to the avoidance of this effect.

Visual outcomes after implantation of a low‐add (+3.25D) diffractive multifocal intraocular lens

Visual outcomes after implantation of a low‐add (+3.25<scp>D</scp>) diffractive multifocal intraocular lens

Clinical evaluation of a new pupil independent diffractive multifocal intraocular lens with a +2.75 D near addition: a European multicentre study

PurposeTo evaluate the clinical outcomes after cataract surgery with implantation of a new diffractive multifocal intraocular lens (IOL) with a lower near addition (+2.75 D.).Methods143 eyes of 85 patients aged...

Intermediate and near visual acuity of an aspheric, bifocal, diffractive multifocal intraocular lens with +3.25 D near addition.

To evaluate the clinical outcomes after cataract surgery with implantation of a new diffractive multifocal intraocular lens with a lower near addition. A prospective multicenter clinical study including 44 eyes of 44 patients (age range: 43 to 82 years) that underwent cataract surgery with implantation of the Tecnis ZLB00 multifocal intraocular lens (Abbott Medical Optics, Santa Ana, CA). Changes in uncorrected and corrected distance, intermediate, and near visual acuity, and manifest refraction were evaluated during a 3-month follow-up. Additionally, patients were asked about photic phenomena and spectacle dependence. Postoperative spherical equivalent was within 0.50 and ± 1.00 diopters of emmetropia in 91.2% and 100% of eyes, respectively. Postoperative monocular uncorrected distance, near, and intermediate visual acuities were 0.10 logMAR (20/25 Snellen) or better in 82.5%, 86.5%, and 68.8% of eyes, respectively. All eyes achieved monocular corrected distance and near visual acuity of 0.10 logMAR (20/25 Snellen) or better. All patients reported to be satisfied with the outcomes of the surgery. Only 6 patients (13.6%) required the use of spectacles for some daily activities postoperatively, and 8 patients (18.2%) reported mild perception of halos. The introduction of low addition multifocal intraocular lenses follows a trend to increase intermediate visual acuity. Still, a near addition of +3.25 diopters reached satisfying near results and led to high patient satisfaction.

Cataract Surgical Problem: May consultation #1

Figure 1. Mydriasis shows a sulcus-fixated IOL with 2-hole PMMA optic and polypropylene loops fixated in the sulcus. The iris exhibits a basal coloboma at 12 o'clock, giving visual access to the anterior capsule rim sealed to the posterior capsule. The IOL optic is decentered inferiorly and slightly tilted but definitely shows a positive distance to the pupillary margin with the pupil undilated. A 79-year-old woman had cataract surgery with intraocular lens (IOL) implantation in the left eye in 1990. A 3-piece IOL with a poly(methyl methacrylate) (PMMA) optic with positioning holes and polypropylene loops was fixated in the ciliary sulcus. In 1993, the right eye also had cataract surgery with implantation of a PMMA diffractive multifocal IOL. In 2013, 23 years after the first surgery, the patient started having repeated attacks of blurred vision and pain in the left eye, mostly after bowing her head. These symptoms subsided within several hours. When immediately consulting with the local ophthalmologist on 2 such occasions, a 3+ erythrocyte Tyndall phenomenon was found in the anterior chamber aqueous and trickle marks (traces) were found in the inferior sector of the cornea; the intraocular pressure (IOP) approached 60 mm Hg. The patient was treated with pressure-lowering eyedrops and acetazolamide tablets; by the following day, the condition of the eye had returned to normal. The attacks, however, recurred with increasing frequency. On 1 such occasion, 1 IOL loop was reported to be visible in the peripheral coloboma at 12 o’clock; however, this was not the case when the patient returned later. When these attacks persisted, the patient was finally referred to an anterior segment specialist. When the patient first presented, the pupil in the left eye was small, the IOL optic was at a distinct distance to the pupillary margin, and no IOL loop was visible in the slit-shaped peripheral coloboma. The refraction was 1.50 +1.25 175 in the right eye and 1.50 +0.50 5 in the left eye. The decimal corrected distance visual acuity (CDVA) was 0.8 and 0.9, respectively. Both central capsules where clear, the retina and macula were normal, and the optic nerve head was vital and centrally excavated with a cup-to-disc ratio of 0.4 in the right eye and 0.3 in the left eye. On full pupil dilation, a 3-piece IOL with a PMMA optic with positioning holes and polypropylene loops was exposed in the left eye (Figure 1). The loops were fixated in the ciliary sulcus, and the slightly tilted optic was decentered inferiorly. The aqueous was clear, and the IOPwas 17mmHg. No change in haptic position or IOL rotation could be induced by gently massaging the limbus with a cotton swab under topical anesthesia. The patient was asked to immediately return if the symptoms recurred. Ten days later, she presented 2 hours after another attack. The biomicroscopic findings in the left eye were as described above, and the

Visual outcomes in eyes with a distance-dominant diffractive multifocal intraocular lens with low near addition power

AimTo compare monocular and binocular visual function between eyes with a distance-dominant diffractive multifocal intraocular lens (IOL) with low addition power (+2.5 dioptres (D)) and eyes with a monofocal IOL.MethodsSixty-four...

Visual Outcomes at 12Months in Patients Following Implantation of a Diffractive Multifocal Intraocular Lens.

IntroductionThe aim of this study was to assess distance, intermediate, and near visual acuity, contrast sensitivity, and patient satisfaction outcomes of a multifocal intraocular lens (IOL).MethodsThis multicenter, prospective clinical study was conducted at seven study sites in Turkey. Patients who underwent bilateral cataract removal and implantation of a diffractive, acrylic, hydrophobic, multifocal IOL (Acriva UD Reviol MFB 625; VSY Biotechnology, Istanbul, Turkey) were included. The uncorrected and best corrected distance visual acuities (UCDVA and BCDVA), uncorrected and best corrected intermediate visual acuities (UCIVA and BCIVA), and uncorrected and best corrected near visual acuities (UCNVA and BCNVA) were measured preoperatively and at postoperative 1, 6, and 12 months. Distance and near visual acuity scores (VAS) contrast sensitivities were measured at these time points. Quality of life was evaluated by visual function-14 (VF-14) questionnaire.ResultsTwo hundred eyes of 100 patients were included. Monocular and binocular visual acuities at all distances showed improvement at postoperative 12 months compared to preoperative measurements (P < 0.001). Monocular and binocular UCIVA and binocular BCIVA at postoperative 12 months were significantly improved compared to measurements at 1 month (P < 0.001). Binocular contrast sensitivity at distance showed significant improvement from postoperative 1 month to postoperative 12 months, except for 3 cycles per degree (cpd; without glare) and 18 cpd (with glare). VAS improved from 75.96 at postoperative 1 month to 76.85 at postoperative 12 months. VF-14 score was 98.2 ± 4.6.ConclusionThe Acriva UD Reviol MFB 625 appears to provide a good level of distance and near visual acuity, quality of life, and patient satisfaction. Further studies with longer follow-up will provide valuable insight into the long-term stability of these visual outcomes.Electronic supplementary materialThe online version of this article (doi:10.1007/s40123-015-0032-4) contains supplementary material, which is available to authorized users.

Light-distortion analysis as a possible indicator of visual quality after refractive lens exchange with diffractive multifocal intraocular lenses

To study the perception of light distortion after refractive lens exchange (RLE) with diffractive multifocal intraocular lenses (IOLs). Clínica Oftalmológica das Antas, Porto, Portugal. Retrospective comparative study. Refractive lens exchange was performed with implantation of an AT Lisa 839M (trifocal) or 909MP (bifocal toric) IOL, the latter if corneal astigmatism was more than 0.75 diopter (D). The postoperative visual and refractive outcomes were evaluated. A prototype light-distortion analyzer was used to quantify the postoperative light-distortion indices. A control group of eyes in which a Tecnis ZCB00 1-piece monofocal IOL was implanted had the same examinations. A trifocal or bifocal toric IOL was implanted in 66 eyes. The control IOL was implanted in 18 eyes. All 3 groups obtained a significant improvement in uncorrected distance visual acuity (UDVA) (P < .001) and corrected distance visual acuity (CDVA) (P = .001). The mean uncorrected near visual acuity (UNVA) was 0.123 logMAR with the trifocal IOL and 0.130 logMAR with the bifocal toric IOL. The residual refractive cylinder was less than 1.00 D in 86.7% of cases with the toric IOL. The mean light-distortion index was significantly higher in the multifocal IOL groups than in the monofocal group (P < .001), although no correlation was found between the light-distortion index and CDVA. The multifocal IOLs provided excellent UDVA and functional UNVA despite increased light-distortion indices. The light-distortion analyzer reliably quantified a subjective component of vision distinct from visual acuity; it may become a useful adjunct in the evaluation of visual quality obtained with multifocal IOLs. No author has a financial or proprietary interest in any material or method mentioned.

Clinical outcomes with a new microincisional diffractive multifocal IOL.

BackgroundTo evaluate the refractive outcomes and the optical performance as well as the quality of life in patients implanted with a new diffractive multifocal intraocular lens (IOL).MethodsProspective, clinical study including 41 cases of patients who underwent cataract surgery and were divided in two groups: group 1, including 20 eyes implanted with the multifocal IOL SeeLens MF (Hanita Lenses, Israel); group 2, 21 eyes implanted with the Acrysof SA60AT IOL. Visual acuity, defocus curve, intraocular aberrations, contrast sensitivity function and quality of life were assessed during a follow up period of 6 months.ResultsSignificant improvement was observed in the uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) in both groups (p < 0.02). The multifocal group showed better results in terms of uncorrected near visual acuity (UNVA) and distance-corrected near visual acuity (DCNVA) (p < 0.01). Comparison of both groups showed better visual acuities for the multifocal IOL group in defocus levels from -3.0 D to -1.50 D (p ≤ 0.01). At 6 months, there was a significant reduction of the internal higher order aberrations (p ≤ 0.04). A significant increase in scotopic contrast sensitivity was detected for 6 cycles/° spatial frequency during follow up (p = 0.04), but no significant changes were observed for the rest of spatial frequencies (p ≥ 0.06). Visual Functioning Index (VF-14) questionnaire showed that patients reported high levels of satisfaction when performing daily tasks.ConclusionsThe SeeLens MF IOL is able to successfully restore distance, near and intermediate visions after cataract surgery. It also provides functional intermediate vision with optimal intraocular optical quality.

Clinical Results and Optical Quality of Diffractive Multifocal Intraocular Lens

Purpose: To compare postoperative clinical outcomes, optical quality, and patient satisfaction between two types of diffractive multifocal intraocular lens (IOL, Acri Lisa 366D and Acrysof ReSTOR +3.00 D). Methods: In a total of 68 eyes, one of two diffractive multifocal IOL (Acri Lisa 366D and Acrysof ReSTOR +3.00 D) was implanted after cataract extraction. Visual acuity was measured postoperatively at one week, 1 month, and 6 months. Contrast sensitivity, wavefront aberration, and visual function were determined via questionnaire at postoperative 1 month. Results: Intermediate visual acuity of Acri Lisa 366D and Acrysof ReSTOR at 6 months were 0.31 ± 0.14, and 0.24 ± 0.11 (log MAR), respectively. At 6 months, near and distant visual acuity results showed no significant differences between the two groups. The photopic contrast sensitivity of Acri Lisa 366D at 6 cycles/degree was 55.36 ± 7.40 and showed significant differences with Acrysof ReSTOR (47.25 ± 9.67). The mesopic contrast sensitivity values of Acri Lisa 366D and Acrysof ReSTOR were 40.26 ± 11.38 and 28.97 ± 10.45, respectively, and the spherical aberration values were 0.037 ± 0.039 μm and 0.105 ± 0.066 μm. The spherical aberration of Acri Lisa 366D was significantly lower than that of Acrysof ReSTOR. Total and high order aberration, coma, and trefoil show no significant differences between the two groups. Conclusions: The Acri Lisa 366D multifocal IOL showed better contrast sensitivity and spherical aberration compared to Acrysof ReSTOR multifocal IOL, which had an effective intermediate visual acuity. J Korean Ophthalmol Soc 2015;56(12):1867-1873

Comparison of Clinical Outcomes between Diffractive and Refractive Multifocal Intraocular Lens with Same Near Added

Purpose: To compare the clinical outcomes between refractive-type multifocal intraocular lenses (IOL) (Lentis Mplus LS 313, Oculentis GmbH., Berlin, Germany) and diffractive-type multifocal IOL (Acrysof Restor; SN6AD1, Alcon Lab., Fort Worth, TX, USA) with same near added. Methods: We evaluated 30 eyes implanted with Lentis Mplus IOL and 33 eyes implanted with Acrysof Restor IOL after phacoemulsification. The distant, intermediate, and near uncorrected visual acuities of the 2 groups were evaluated at 2 weeks and 1, 3, and 6 months postoperatively. Optical quality obtained using the Optical Quality Analysis System II (OQAS II, Visiometrics, Castelldefels, Barcelona, Spain), higher-order aberrations (HOAs), and patient satisfaction questionnaire of the 2 groups were evaluated at 3 months postoperatively. Results: The visual acuity of intermediate 100 cm was statistically better in the Lentis Mplus group (p < 0.05). There were no significant differences between the 2 groups with distant, intermediate 63 cm, and near vision. At the 3-month postoperative follow-up, objective scatter index, modulation transfer function (MTF) cutoff value, and pseudo-accommodation range measured by OQAS II showed no differences between the 2 groups, but Strhel ratio was higher in the Acrysof Restor group. HOAs of 5 mm and 6 mm increased significantly in the Lentis Mplus group. No significant differences were found in the patient satisfaction questionnaire. Conclusions: Both refractive and diffractive-type multifocal IOL implantation in patients with cataracts and presbyopia offered good and comparable visual acuity at distance and near. However, the Lentis Mplus IOL provided better intermediate vision than the Acrysof Restor IOL. J Korean Ophthalmol Soc 2015;56(6):875-884

Usefulness of Implantation of Diffractive Multifocal Intraocular Lens in Eyes with Long Axial Lengths.

Purpose. This study retrospectively analyzed the postoperative visual functions of myopic eyes implanted with multifocal intraocular lens (IOL) to evaluate the efficacy of multifocal IOL in highly myopic eyes. Methods. We studied 61 patients (96 eyes) who were implanted with multifocal IOL ZMA00 or ZMB00 (Abbott Medical Optics). The patients were stratified into two groups by axial length: 26 mm or above (AL ≥ 26 group) and below 26 mm (AL < 26 group). Postoperative corrected and uncorrected distance (5 m) and near (30 cm) visual acuity (VA), contrast sensitivity, and depth of focus were compared between two groups. Results. In the AL ≥ 26 group and the AL < 26 group, the mean ± standard deviation uncorrected distance logMAR VA at 12-month postoperative follow-up was −0.04 ± 0.11 and −0.01 ± 0.14, respectively; and the corrected distance VA was −0.17 ± 0.08 and −0.14 ± 0.07, with no significant differences between two groups (p = 0.558 and 0.101; Mann-Whitney U test). For near VA, the corresponding uncorrected VA was 0.06 ± 0.08 and 0.05 ± 0.09; and distance-corrected VA was 0.01 ± 0.06 and 0.01 ± 0.02, with no significant differences between two groups (p = 0.572, and 0.157; Mann-Whitney U test). Conclusion. The present study demonstrates that it is possible to achieve good uncorrected near and distance VA following implantation of multifocal IOL in eyes with long axial lengths.

Refractive Lens Exchange

Refractive lens exchange (RLE) still has a role in young age with anisometropia, or in an eye that is anatomically not suitable for phakic intraocular lens (IOL) implantation or in high hypermetropia. Furthermore, in the presence of water vacuoles in the crystalline lens above the age of 40, it is recommended to perform RLE rather than phakic IOL implantation. Multifocal refractive IOLs are designed with several optical zones on the IOL. Apodised diffractive multifocal IOL has gradual diffractive steps on the IOL implant that create a smooth transition between focal points. RLE is a surgery with the same risks of a cataract surgery. Complications do occur in RLE. The mean incidence of retinal detachment is 1 % while the mean incidence of cystoid macular oedema is 0.1 %. Contraindications include unstable refraction, amblyopia and the presence of certain eye pathologies as age-related macular degeneration, glaucoma, diabetic retinopathy and a high risk of retinal detachment.

Impact of intraocular lens material and design on light scatter: In vitro study

To determine the typical in vitro straylight levels for intraocular lenses (IOLs) of different materials and designs. Abbott Medical Optics, Inc., Groningen, the Netherlands. Experimental study. Two optical bench setups were used to determine baseline straylight levels of IOLs placed in a saline-filled cuvette: one for forward scatter positions between 0.6 and 3.0 degrees and one for positions up to 22.0 degrees. Line-spread functions were measured using the small-angle setup, and scattered light intensity was measured using the wide-angle setup. From these measurements, the angular dependent straylight parameter was calculated. Ten IOLs of different materials (hydrophobic and hydrophilic) and designs (monofocal or diffractive multifocal and spheric or aspheric) were studied, and their measured straylight levels were compared with the levels in a 20-year-old and a 70-year-old healthy noncataractous human crystalline lens. Irrespective of the material or design, monofocal IOLs had straylight levels below or close to those of a 20-year-old human crystalline lens. Diffractive multifocal IOLs had straylight levels higher than those of monofocal IOLs but less than those of a 70-year-old human crystalline lens. With increasing angle, hydrophobic IOLs showed a gradual decrease in straylight level. After an initial decrease, hydrophilic IOLs showed an increase in straylight level for larger angles. The baseline straylight levels of IOLs were design and material dependent (hydrophobic < hydrophilic; monofocal < diffractive multifocal). Most monofocal IOLs had straylight levels below the levels in a 20-year-old human crystalline lens.