Comparison of visual results with accommodating intraocular lenses versus mini-monovision with a monofocal intraocular lens

BCLA CLEAR Presbyopia: Definitions

Presbyopia is often the first sign of ageing experienced by humans. Standardising terminology and adopting it across the BCLA CLEAR Presbyopia reports, improves consistency in the communication of the evidence-based understanding of this universal physiological process. Presbyopia can be functionally and psychologically debilitating, especially for those with poor access to eyecare. Presbyopia was defined as occurring when the physiologically normal age-related reduction in the eye's focusing range reaches a point that, when optimally corrected for far vision, the clarity of vision at near is insufficient to satisfy an individual's requirements. Accommodation is the change in optical power of the eye due to a change in crystalline lens shape and position, whereas pseudo-accommodation is the attainment of functional near vision in an emmetropic or far-corrected eye without changing the refractive power of the eye. Other definitions specific to vision and lenses for presbyopia were also defined. It is recommended that these definitions be consistently adopted in order to standardise future research, clinical evaluations and education.

Visual outcomes, spectacle independence, and patient satisfaction of pseudophakic mini-monovision using a new monofocal intraocular lens

Modified monovision-or "mini-monovision"-is an alternative method to multifocal intraocular lenses (IOLs) for treating presbyopia. This study aimed to evaluate the clinical outcomes of patients bilaterally implanted with the new enhanced monofocal Tecnis Eyhance (ICB00) IOLs with the mini-monovision technique to improve near vision. In this retrospective case series, the medical records of 50 patients (100 eyes) who underwent bilateral cataract surgery were reviewed. Patients were divided into the Emmetropia and Mini-monovision groups based on the postoperative spherical equivalent and residual myopia. The binocular visual acuity for far (4 m), intermediate (66 cm), and near (40 cm) distances, binocular defocus curves, contrast sensitivity, visual symptoms, spectacle independence, and patient satisfaction rates were evaluated at 3 months postoperatively. The binocular uncorrected distance and intermediate visual acuities, contrast sensitivity, incidence of photic phenomena, and patient satisfaction were not significantly different between the two groups (p > 0.05). However, the binocular uncorrected near visual acuities and spectacle independence rates were significantly better in the Mini-monovision group (p < 0.001). Conclusively, the pseudophakic mini-monovision technique using enhanced monofocal IOLs may be a promising option for presbyopia correction in patients unsuitable for multifocal IOLs.

Long-Term Evaluation of Visual Outcomes and Patient Satisfaction after Binocular Implantation of a Bioanalogic Lens

Purpose

Long-term evaluation of the visual refractive outcomes and the quality of life after implantation of the WIOL-CF (Medicem, Czech Republic) in both eyes.

Design

retrospective, nonrandomized noncomparative case series.

Methods

50 eyes of 25 patients, including 11 women (44%) and 14 men (56%). The age range of the patients was 38 to 77 years (mean age 55.48 ± 10.97 years). All patients underwent bilateral implantation of the WIOL-CF. Exclusion criteria were previous ocular surgeries except for cataract surgery and refractive lens exchange, irregular corneal astigmatism of >1.0 diopter, and ocular pathologies or corneal abnormalities. Postoperative examinations were performed at 14 days and 3, 6, 12 months of surgery; the last follow-up was between 24 and 36 months after the procedure. All exams included manifest refraction, monocular uncorrected visual acuity (UCVA) and distance-corrected visual acuity (DCVA) in 5 m (Snellen), monocular uncorrected visual acuity in 70 cm and 40 cm (Jeager) and binocular UCVA, DCVA in 5 m, 70 cm, and 40 cm, binocular contrast sensitivity (CS) under photopic conditions, binocular defocus curves, high-order aberrations, quality-of-vision VF-14 questionnaire, and spectacle independence.

Results

Significant improvement in monocular visual acuity at all distances was demonstrated; the mean postoperative spherical equivalent was 0.32 ± 0.45D. The postoperative means of binocular distance UCVA and BCVA were also improved (p < .001) and so were the mean uncorrected intermediate VA (2.053 ± 1.268) and near uncorrected VA (2.737 ± 1.447). There was a significant improvement in contrast sensitivity at all spatial frequencies and higher-order aberration, compared to preoperative results.

Conclusions

The evaluation of a WIOL-CF showed good distance, intermediate, and near visual acuity. Contrast sensitivity increased after surgery in all spatial frequencies. Patient satisfaction was high despite some optical phenomena. The rate of postoperative spectacle independence also turned out high. Financial Disclosure. No author has a financial or proprietary interest in any material or method mentioned.

Multifocal and Accommodating Intraocular Lenses for the Treatment of Presbyopia: A Report by the American Academy of Ophthalmology

PURPOSE

To review the published literature assessing the efficacy and safety of presbyopia-correcting intraocular lenses (IOLs) for the treatment of presbyopia after cataract removal.

METHODS

Literature searches were undertaken in January 2018 and September 2020 in the PubMed, Medline, and Cochrane Library databases. This yielded 761 articles, of which 34 met the criteria for inclusion in this assessment and were assigned a level of evidence rating by the panel methodologist. Thirteen studies were rated level I and 21 studies were rated level II.

RESULTS

Presbyopia-correcting lenses were effective at improving distance and near visual acuity after cataract surgery. Near acuity at different focal lengths was related directly to the effective add power of multifocal and extended depth-of-focus (EDOF) IOLs. Most multifocal and EDOF lenses that were compared with a control monofocal lens demonstrated that patient-reported spectacle independence was superior to the monofocal lens. All patients who had multifocal and EDOF lenses implanted showed decreased contrast sensitivity and reported more visual phenomena as compared with control participants who received monofocal lenses.

CONCLUSIONS

Presbyopia-correcting lenses improve uncorrected near and distance visual acuity and decrease spectacle dependence after cataract surgery. Mesopic contrast sensitivity is decreased compared with monofocal lenses, and patient-reported visual phenomena are more likely in patients receiving multifocal or EDOF lenses.

Cataract surgery in Kinshasa-Is there a place for "Monovision"?

OBJECTIVES

Monovision is a method of correcting presbyopia where one eye is focused for far and the other for near vision. It is a simple, cost-effective approach to overcome the loss of accommodation with age and to become spectacles independent.

METHODOLOGY

About 50 patients, where bilateral cataract extraction was indicated, were included in this study performed at the St. Joseph's Eye Hospital in Kinshasa (DR Congo). Small incision cataract surgery technique (SICS) was applied with the implantation of 6 mm PMMA lenses in the capsular bag. IOL refractive power choice was made to achieve a post-operative refraction of -0.5 dpt for the eye selected for far vision. The second eye received an implant heading for a post-operative myopia of -1.5 dpt suitable for intermediated and near vision. According to the literature, monovision criteria have been regarded as fulfilled when (a) far vision was 0.5 (logMAR) or better and (b) near vision was P3 (0.40, Decimal 32 cm) or better. Spectacle dependence after bilateral cataract surgery heading for monovision was analysed using a dedicated questionnaire.

RESULTS

Out of all 50 patients 22 (44%) fulfilled the above defined criteria of monovision in terms of post-operative refraction and visual acuity. About 19 out of these 22 (86.3%) patients were happy without glasses. Two of them used bifocal spectacles, whereas the remaining patient refused spectacles. About 28 patients did not fulfill monovision criteria. Out of these 28 patients, however, 9 (32.1%) of them are happy without glasses.

CONCLUSION

In view of the described local circumstances aiming for monovision after bilateral cataract surgery is a suitable approach to optimise cataract surgical outcomes with no extra costs for surgery but considerable improvement of patient's visual performance in daily life.

Lens-based surgical correction of presbyopia. Where are we in 2020?

INTRODUCTION

Presbyopia is the progressive and irreversible loss of accommodation due to aging. It is one of the main causes of loss of quality of life in people from 45 years of age, due to the, often novel, dependence on spectacles. The eagerness to correct it by ophthalmologists impulsed by the desire of millions of people who suffer from it, has become one of the main drivers for the development of intraocular lens (IOL) technology over the last twenty years.

MATERIAL AND METHODS

This review briefly presents the different alternatives that have allowed us to improve the crystalline lens surgical approach of presbyopia; from monofocal lenses and monovision technique, accommodative, refractive, and diffractive multifocal lenses, and finally the most recent extended depth of focus/field lenses known as EDOFs.

RESULTS

Each IOL has its advantages, limitations and disadvantages. Furthermore, there is no single lens that suits the needs of all patients.

CONCLUSIONS

It is necessary to know the variety of lenses available, and to have an in-depth understanding of their optical properties, as well as the impact that these will have later on their clinical performance and on the visual quality of the patients. This should help us to select the best alternative for each of them.

Clinical application of accommodating intraocular lens

The present review describes recent advances in application of accommodating intraocular lenses (AIOLs). Standard monofocal intraocular lenses (MIOLs) only correct distance vision, while AIOLs are designed to allow both good distance vision and near vision, which is achieved through the contraction and relaxation of ciliary muscles by providing transformation of the axial movement or curvature of the lens. Thus, AIOLs may be a better choice for those patients who demand a higher level of visual performance. Since techniques to analyze the performance of AIOLs have not been standardized, and there is a variety of both subjective and objective methods, it is hard to measure the performance of these intraocular lenses. By evaluating advantages and disadvantages of various AIOLs, and introducing techniques for measurement the performance postoperative, this paper can provide some relative information on choosing the type of AIOLs in the clinic.

Monovision Versus Multifocality for Presbyopia: Systematic Review and Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

Refractive surgery in presbyopia tends to achieve spectacle independence with minimal optical disturbances. We compared monovision to multifocality procedures regarding these outcomes.

METHODS

We conducted a systematic review of published (till November 21, 2016) randomized controlled trials (RCTs) comparing any monovision to any multifocality method or comparing different monovision/multifocality methods to each other that enabled direct or indirect comparisons between particular monovision and particular multifocality procedures in presbyopic patients undergoing cataract-related or unrelated surgery in respect to spectacle independence, unaided binocular visual acuity (VA), contrast sensitivity (CS), and adverse events.

RESULTS

Three trials comparing monovision (monofocal lenses, LASIK) to multifocal intraocular lenses (MFIOLs; Isert refractive or Tecnis diffractive) and 6 comparing other MFIOLs to Tecnis were included (1-12 months duration). Spectacle independence. All reporting trials were of sufficient quality. Directly, pseudophakic monovision was inferior to Isert (1 trial, N = 75, RR = 0.49, 95% CI 0.28-0.80) and Tecnis (1 trial, N = 211, RR = 0.36, 95% CI 0.25-0.52) in cataract patients, and LASIK was comparable to Tecnis (1 trial, N = 100, RR = 0.93, 0.78-1.10) in refractive surgery. In network meta-regression (6 trials, 14 arms) pseudophakic monovision in cataract patients was inferior to Tecnis. Indirect data suggest also that it is inferior (ReZoom refractive, TwinSet diffractive) or tends to be inferior (Array refractive) to other MFIOLs. LASIK was comparable to Tecnis in refractive surgery. Indirect data suggest also that it tends to superiority vs. ReZoom or Array refractive MFIOLs. Adverse events. No pooling was possible (heterogeneity of assessment and reporting). One quality direct RCT indicated less glare/dazzle with pseudophakic monovision vs. Tecnis in cataract patients. Unaided VA and CS data were burdened with heterogeneity (assessment, reporting) and insufficient quality.

CONCLUSIONS

Randomized comparisons of monovision to multifocality are scarce. Existing estimates regarding spectacle independence (imprecision, indirectness) and particularly regarding unaided VA and CS (assessment/reporting heterogeneity, bias, imprecision, indirectness) are burdened with uncertainty. Dysphotopsia is less common with monovision, but estimate uncertainty is high (bias, imprecision).

Anterior Segment Biometry of the Accommodating Intraocular Lens and its Relationship With the Amplitude of Accommodation

OBJECTIVES

To evaluate the anterior segment biometry of the Tetraflex accommodating intraocular lens (AIOL) and the contribution of forward movement to the amplitude of accommodation (AMP).

METHODS

Patients who underwent phacoemulsification with implantation of Tetraflex AIOLs and control nonaccommodating intraocular lenses were imaged by custom-built, long scan depth spectral-domain optical coherence tomography at relaxed and maximal accommodative states. Anterior segment biometry was performed and correlated with the clinical manifestation including AMP.

RESULTS

Patients in the Tetraflex group showed better distance-corrected near visual acuity (logMAR 0.43±0.10 vs. logMAR 0.51±0.10, P<0.05) and greater AMP (1.99±0.58 diopters [D] vs. 1.59±0.45 D, P<0.05) compared with the control group. The measurement of the postoperative anterior chamber depth (ACD) during accommodation showed a forward movement of the AIOLs in 16 eyes (69.6%). Compared with the control group, a greater proportion of cases in the Tetraflex group experienced forward movement (χ test, P<0.001). The AMP in the AIOL group negatively correlated with changes in postoperative ACD during accommodation (r=-0.47, P<0.05), whereas AMP in the control group negatively correlated with postoperative pupil diameter (r=-0.57, P<0.05).

CONCLUSIONS

The Tetraflex AIOLs seemed to have a tendency for forward movement; however, the slight forward axial shifts of the Tetraflex AIOL during natural accommodation may not produce a clinically relevant change in optical power.

Accommodative intraocular lenses: where are we and where we are going

Presbyopia still remains the last frontier of refractive surgery. Its surgical management is under constant evolution due to the limitations that exist today with respect to its management, which is probably in relation with the multifactorial basis in which presbyopia is clinically developed in the human. Until currently, virtually all surgical techniques that have been proposed for its correction are based on the induction of pseudoaccommodation in the presbyopic eye, including multifocality. However, the real restoration of accommodation is more complex, and it has been tried by the use of different, so called, “accommodative” pseudophakic intraocular lenses (AIOL). Overall, the reported results with these lenses by independent authors have been modest in relation with the restoration of the accommodative power of the eye and these modest benefits are usually lost with time due to the long term changes in the capsular bag. This fact made these lenses to be almost abandoned in the last few years, but there are currently other AIOL models being used with innovative mechanisms of action and different anatomical support outside the capsular bag that offer encouraging preliminary results that could bring a new potential of application to these types of lenses.

In this article, we will update the modern refractive surgeon about the fundamentals and provide updated information about the outcomes of AIOLs by reviewing the concept of accommodation, the different attempts that have been accomplished in the past, their demonstrated published results in human clinical trials, and the future alternatives that may arrive in the near future.

A systematic review of pseudophakic monovision for presbyopia correction

A systematic review of the recent literature regarding pseudophakic monovision as a reliable methods for presbyopia correction was performed based on the PubMed, MEDLINE, Nature and the American Academy of Ophthalmology databases in July 2015 and data from 18 descriptive and 12 comparative studies were included in this narrative review. Pseudophakic monosvision seems to be an effective method for presbyopia with high rates of spectacles independence and minimal dysphotopsia side-effects, that should be considered by the modern cataract surgeons.

Patient-Centered and Visual Quality Outcomes of Premium Cataract Surgery: A Systematic Review

Purpose

Over 8 million cataract surgeries are performed in the United States and the European Union annually, with many patients choosing to pay out of pocket for premium options including premium intraocular lens implants (IOLs) or laser-assisted cataract surgery (LACS). This report provides a systematic review evaluating patient-centered and visual quality outcomes comparing standard monofocal IOLs to premium cataract surgery options.

Methods

PubMed and EMBASE were searched for publications published between January 1, 1980, and September 18, 2016, on multifocal, accommodative, and toric IOLs, monovision, and LACS, which reported on 1) dysphotopsias, 2) contrast sensitivity, 3) spectacle independence, 4) vision-related quality of life or patient satisfaction, and 5) IOL exchange.

Results

Multifocal lenses achieved higher rates of spectacle independence compared to monofocal lenses but also had higher reported frequency of dysphotopsia and worse contrast sensitivity, especially with low light or glare. Accommodative lenses were not associated with reduced contrast sensitivity or more dysphotopsia but had only modest improvements in spectacle independence compared to monofocal lenses. Studies of monovision did not target a sufficiently myopic outcome in the near-vision eye to achieve the full potential for spectacle independence. Patients reported high levels of overall satisfaction regardless of implanted IOL. No studies correlated patient-reported outcomes with patient expectations.

Conclusions

Studies are needed to thoroughly compare patient-reported outcomes with concomitant patient expectations. In light of the substantial patient costs for premium options, patients and their surgeons will benefit from a better understanding of which surgical options best meet patients’ expectations and how those expectations can be impacted by premium versus monofocal—including monovision—options.

Positional accommodative intraocular lens power error induced by the estimation of the corneal power and the effective lens position

Purpose:

To evaluate the predictability of the refractive correction achieved with a positional accommodating intraocular lenses (IOL) and to develop a potential optimization of it by minimizing the error associated with the keratometric estimation of the corneal power and by developing a predictive formula for the effective lens position (ELP).

Materials and Methods:

Clinical data from 25 eyes of 14 patients (age range, 52–77 years) and undergoing cataract surgery with implantation of the accommodating IOL Crystalens HD (Bausch and Lomb) were retrospectively reviewed. In all cases, the calculation of an adjusted IOL power (P_IOLadj) based on Gaussian optics considering the residual refractive error was done using a variable keratometric index value (n_kadj) for corneal power estimation with and without using an estimation algorithm for ELP obtained by multiple regression analysis (ELP_adj). P_IOLadj was compared to the real IOL power implanted (P_IOLReal, calculated with the SRK-T formula) and also to the values estimated by the Haigis, HofferQ, and Holladay I formulas.

Results:

No statistically significant differences were found between P_IOLReal and P_IOLadj when ELP_adj was used (P = 0.10), with a range of agreement between calculations of 1.23 D. In contrast, P_IOLReal was significantly higher when compared to P_IOLadj without using ELP_adj and also compared to the values estimated by the other formulas.

Conclusions:

Predictable refractive outcomes can be obtained with the accommodating IOL Crystalens HD using a variable keratometric index for corneal power estimation and by estimating ELP with an algorithm dependent on anatomical factors and age.

The Predictability of Preoperative Pilocarpine-Induced Lens Shift on the Outcomes of Accommodating Intraocular Lenses Implanted in Senile Cataract Patients

Purpose. To evaluate the predictability of lens shift induced by pilocarpine (LSPilo) on the outcomes of accommodating intraocular lens (Acc-IOL) implantation. Methods. Twenty-four eyes of 24 senile cataract patients who underwent phacoemulsification and Acc-IOL implantation were enrolled. LSPilo was evaluated with anterior segment optical coherence tomography (AS-OCT). At 3 months postoperatively, the best corrected distance visual acuities (BCDVA), distance-corrected near visual acuities (DCNVA), and subjective and objective accommodations were measured. IOL shifts under accommodation stimulus (IOLSAcc) were evaluated with AS-OCT. Results. The mean LSPilo was 112.29 ± 30.72 µm. LSPilo was not associated with any preoperative parameters. The mean IOLSAcc was 130.46 ± 42.71 µm. The mean subjective and objective accommodation were 1.54 ± 0.39 D and 1.27 ± 0.41 D, respectively. The mean postoperative BCDVA and DCNVA (log MAR value) were 0.22 ± 0.11 and 0.24 ± 0.12, respectively. LSPilo positively correlated with IOLSAcc (r = 0.541; P = 0.006), subjective accommodation (r = 0.412; P = 0.022), and objective accommodation (r = 0.466; P = 0.045), respectively. Conclusion. LSPilo is an independent preoperative parameter associated with the postoperative Acc-IOL mobility and pseudophakic accommodation. It may offer valuable information for ophthalmologists in determining the suitable candidates for Acc-IOL implantation.

Visual and Refractive Outcomes of Phacoemulsification with Implantation of Accommodating versus Standard Monofocal Intraocular Lenses

Purpose:

To compare distant and near visual function after cataract surgery with implantation of Crystalens HD or Tek-Clear as accommodating intraocular lenses (IOLs), versus SA60AT as a standard IOL.

Methods:

The study included 62 eyes of 58 patients divided into three groups using three different IOLs: Crystalens HD (Bausch and Lomb, NY, USA), Tek-Clear (Tekia, CA, USA) and SA60AT (Alcon, TX, USA) were implanted in 23, 14 and 25 eyes, respectively. Corrected distant visual acuity (CDVA), uncorrected and distance corrected near visual acuities (UCNVA and DCNVA), near point of accommodation (NPA), spectacle freedom and patient satisfaction were assessed six months postoperatively and compared between the three groups.

Results:

After 6 months, all patients showed significant improvement in CDVA with no significant difference among the study groups. However, UCNVA and DCNVA were significantly better in patients implanted with accommodating IOLs. NPA was closest in the Crystalens HD group, followed by Tek-Clear and monofocal SA60AT (P < 0.001). Patients with accommodating IOLs were more likely to become spectacle free and satisfied with their near vision as compared to subjects receiving a monofocal IOL.

Conclusions:

Accommodating IOLs (Crystalens HD and Tek-Clear) effectively reduce the necessity for spectacles after cataract surgery.

Visual Outcomes and Accommodative Response of the Lumina Accommodative Intraocular Lens

PURPOSE

To compare visual acuity, accommodation, and contrast sensitivity of the AkkoLens Lumina accommodative intraocular lens (AkkoLens Clinical b.v., Breda, The Netherlands) with a standard monofocal intraocular lens (IOL).

DESIGN

Randomized clinical trial.

METHODS

The study enrolled 86 eyes with cataract that all required cataract surgery and IOL implantation. The study group included 61 eyes that were implanted with the Lumina. The control group included 25 eyes that were implanted with an Acrysof SA60AT (Alcon, Fort Worth, TX, USA) monofocal IOL. The distance and near visual acuities, contrast sensitivity, and accommodation were measured over a 1-year follow-up period. Accommodation was measured subjectively, using defocus curves, and objectively, with an open-field autorefractor.

RESULTS

Uncorrected (UDVA) and corrected (CDVA) distance visual acuities did not differ significantly between the groups (P ≥ .21) over the 12 months. However, the uncorrected near visual acuity (UNVA) was 0.07 ± 0.08 logRAD for the Lumina group and 0.37 ± 0.19 logRAD for the control group (P < .01) and the corrected distance near visual acuity (CDNVA) was 0.11 ± 0.12 LogRAD for the Lumina group and 0.41 ± 0.15 LogRAD for the control group (P < .01). Defocus curves showed a statistically significant difference between groups for defocus ranging from -4.50 to -0.50 diopters (D) (P < .01) with significantly higher visual acuities for the Lumina group. Subjective accommodation, as determined from defocus curves, was 3.05 ± 1.06, 3.87 ± 1.27, and 5.59 ± 1.02 D for the Lumina group and 1.46 ± 0.54, 2.00 ± 0.52, and 3.67 ± 0.75 D for the control group at visual acuities of 0.10, 0.20, and 0.4 logMAR for both groups, respectively. The objective accommodation, measured by an open-field autorefractor, was 0.63 ± 0.41, 0.69 ± 0.45, 0.91 ± 0.51, and 1.27 ± 0.76 D for the Lumina group and 0.10 ± 0.15, 0.12 ± 0.15, -0.06 ± 0.09 and 0.07 ± 0.10 D for the control group at accommodation stimuli of 2.0, 2.5, 3.0, and 4.0 D, respectively. Contrast sensitivity was the same for both groups (P ≥ .26).

CONCLUSIONS

The Lumina accommodative IOL effectively restores the visual function, accommodation, and contrast sensitivity after cataract surgery with no influence on the postoperative contrast sensitivity.

Comparison of Contrast Sensitivity and Through Focus in Small-Aperture Inlay, Accommodating Intraocular Lens, or Multifocal Intraocular Lens Subjects

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.

Axial movement of the dual-optic accommodating intraocular lens for the correction of the presbyopia: optical performance and clinical outcomes

Presbyopia occurs in the aging eye due to changes in the ciliary muscle, zonular fibers, crystalline lens, and an increased lens sclerosis. As a consequence, the capacity of accommodation decreases, which hampers to focus near objects. With the aim of restoring near vision, different devices that produce multiple focuses have been developed and introduced. However, these devices are still unable to restore accommodation. In order to achieve that goal, dual-optic accommodating Intraocular Lenses have been designed, whose anterior optic displaces axially to increase ocular power, and focus near objects. Although dual-optic accommodating IOLs are relatively new, their outcomes are promising, as they provide large amplitudes of accommodation and a greater IOL displacement than single-optic accommodating IOLs. The outcomes show comfortable near vision, higher patients' satisfaction rates, and minimal postoperative complications like Posterior Capsular Opacification and Anterior Capsular Opacification, due to their design and material.

Accommodative intraocular lens versus standard monofocal intraocular lens implantation in cataract surgery

BACKGROUND

Following cataract surgery and intraocular lens (IOL) implantation, loss of accommodation or postoperative presbyopia occurs and remains a challenge. Standard monofocal IOLs correct only distance vision; patients require spectacles for near vision. Accommodative IOLs have been designed to overcome loss of accommodation after cataract surgery.

OBJECTIVES

To define (a) the extent to which accommodative IOLs improve unaided near visual function, in comparison with monofocal IOLs; (b) the extent of compromise to unaided distance visual acuity; c) whether a higher rate of additional complications is associated the use of accommodative IOLs.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 9), Ovid MEDLINE, Ovid MEDLINE in-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily Update, Ovid OLDMEDLINE (January 1946 to October 2013), EMBASE (January 1980 to October 2013), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to October 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 10 October 2013.

SELECTION CRITERIA

We include randomised controlled trials (RCTs) which compared implantation of accommodative IOLs to implantation of monofocal IOLs in cataract surgery.

DATA COLLECTION AND ANALYSIS

Two authors independently screened search results, assessed risk of bias and extracted data. All included trials used the 1CU accommodative IOL (HumanOptics, Erlangen, Germany) for their intervention group. One trial had an additional arm with the AT-45 Crystalens accommodative IOL (Eyeonics Vision). We performed a separate analysis comparing 1CU and AT-45 IOL.

MAIN RESULTS

We included four RCTs, including 229 participants (256 eyes), conducted in Germany, Italy and the UK. The age range of participants was 21 to 87 years. All studies included people who had bilateral cataracts with no pre-existing ocular pathologies. We judged all studies to be at high risk of performance bias. We graded two studies with high risk of detection bias and one study with high risk of selection bias.Participants who received the accommodative IOLs achieved better distance-corrected near visual acuity (DCNVA) at six months (mean difference (MD) -3.10 Jaeger units; 95% confidence intervals (CI) -3.36 to -2.83, 2 studies, 106 people, 136 eyes, moderate quality evidence). Better DCNVA was seen in the accommodative lens group at 12 to 18 months in the three trials that reported this time point but considerable heterogeneity of effect was seen, ranging from 1.3 (95% CI 0.98 to 1.68; 20 people, 40 eyes) to 6 (95% CI 4.15 to 7.85; 51 people, 51 eyes) Jaeger units and 0.12 (95% CI 0.05 to 0.19; 40 people, binocular) logMAR improvement (low quality evidence). The relative effect of the lenses on corrected distant visual acuity (CDVA) was less certain. At six months there was a standardised mean difference of -0.04 standard deviations (95% CI -0.37 to 0.30, 2 studies, 106 people, 136 eyes, low quality evidence). At long-term follow-up there was heterogeneity of effect with 18-month data in two studies showing that CDVA was better in the monofocal group (MD 0.12 logMAR; 95% CI 0.07 to 0.16, 2 studies, 70 people,100 eyes) and one study which reported data at 12 months finding similar CDVA in the two groups (-0.02 logMAR units, 95% CI -0.06 to 0.02, 51 people) (low quality evidence).The relative effect of the lenses on reading speed and spectacle independence was uncertain, The average reading speed was 11.6 words per minute more in the accommodative lens group but the 95% confidence intervals ranged from 12.2 words less to 35.4 words more (1 study, 40 people, low quality evidence). People with accommodative lenses were more likely to be spectacle-independent but the estimate was very uncertain (risk ratio (RR) 8.18; 95% CI 0.47 to 142.62, 1 study, 40 people, very low quality evidence).More cases of posterior capsule opacification (PCO) were seen in accommodative lenses but the effect of the lenses on PCO was uncertain (Peto odds ratio (OR) 2.12; 95% CI 0.45 to 10.02, 91 people, 2 studies, low quality evidence). People in the accommodative lens group were more likely to require laser capsulotomy (Peto OR 7.96; 95% CI 2.49 to 25.45, 2 studies, 60 people, 80 eyes, low quality evidence). Glare was reported less frequently with accommodative lenses but the relative effect of the lenses on glare was uncertain (RR any glare 0.78; 95% CI 0.32 to 1.90, 1 study, 40 people, and RR moderate/severe glare 0.45; 95% CI 0.04 to 4.60, low quality evidence).

AUTHORS' CONCLUSIONS

There is moderate-quality evidence that study participants who received accommodative IOLs had a small gain in near visual acuity after six months. There is some evidence that distance visual acuity with accommodative lenses may be worse after 12 months but due to low quality of evidence and heterogeneity of effect, the evidence for this is not clear-cut. People receiving accommodative lenses had more PCO which may be associated with poorer distance vision. However, the effect of the lenses on PCO was uncertain.Further research is required to improve the understanding of how accommodative IOLs may affect near visual function, and whether they provide any durable gains. Additional trials, with longer follow-up, comparing different accommodative IOLs, multifocal IOLs and monofocal IOLs, would help map out their relative efficacy, and associated late complications. Research is needed on control over capsular fibrosis postimplantation.Risks of bias, heterogeneity of outcome measures and study designs used, and the dominance of one design of accommodative lens in existing trials (the HumanOptics 1CU) mean that these results should be interpreted with caution. They may not be applicable to other accommodative IOL designs.

Aberrometry in patients implanted with accommodative intraocular lenses

PURPOSE

To evaluate the objective accommodative response, change of aberrations, and depth of focus in eyes implanted with the Crystalens accommodative intraocular lens (IOL) at different accommodative demands.

DESIGN

Prospective, observational study.

METHODS

Eleven cataract patients (22 eyes) who underwent implantation of a Crystalens accommodative IOL, and control groups of 9 normal subjects (17 eyes) and 17 pseudophakic patients (17 eyes) implanted with monofocal IOLs were evaluated. A custom-developed laser ray tracing aberrometer was used to measure the optical aberrations. The monochromatic wave aberrations were described using a sixth-order Zernike polynomial expansion. Measurements were obtained under dilated and natural viewing conditions (for accommodative efforts ranging from 0 to 2.5 diopters [D]). The accommodative response was obtained by analyzing changes in paraxial defocus (associated to changes in defocus) and by evaluating the differences in the effective defocus (associated with defocus, spherical aberrations, and pupil diameter) with the accommodative demand. Depth of focus was estimated from through-focus objective optical quality.

RESULTS

Wave aberration measurements were highly reproducible. Vertical trefoil (Z3(-3)) was the predominant higher-order aberration in the Crystalens group and significantly higher (P < .0001) than in the young group, but similar to the monofocal IOL group. The coma root mean square also was higher (P < .005) in the Crystalens group than in the young group. On average, the defocus term (Z2(0)), astigmatism, or higher-order aberrations did not change systematically with accommodative demand in Crystalens eyes. As found for paraxial defocus, the effective defocus in Crystalens eyes did not show significant differences between conditions: 0.34 ± 0.48 D (far), 0.32 ± 0.50 D (intermediate), and 0.34 ± 0.44 D (near). Depth of focus was statistically significantly higher in the Crystalens eyes than in the control groups.

CONCLUSIONS

The accommodative response of eyes implanted with the Crystalens accommodative IOLs, measured objectively using laser ray tracing aberrometry, was lower than 0.4 D in all eyes. Several subjects showed changes in astigmatism, spherical aberration, trefoil, and coma with accommodation, which must arise from geometrical and alignment changes in the lens with accommodative demand. Pseudoaccommodation from increased depth of focus may contribute to near vision functionality in Crystalens-implanted patients.