IOL Design Research Articles

Introduction and overview

SummaryPCO remains the commonest complication of cataract surgery and is a particular problem with presbyopia correcting multifocal IOLs which are more sensitive to mild PCO and it remains the barrier to a truly accommodating IOL. This presentation reviews the current clinical status of PCO prevention and in particular the contribution of IOL material and design. Hydrophobic materials appear to induce less PCO than hydrophilic polymers and the reasons for this will be discussed. Square edge profile IOLs have reduced the incidence of PCO but delay rather than cure the problem, edge profile quality is however is very variable and this has clinical implications. Haptic design also affects PCO performance. New ‘open bag’ IOL designs appear to offer a significant improvement in PCO prevention.

Pseudophakic photopsia – Optical simulations with a model eye to evaluate IOL design and material

AbstractPurpose Photopic phenomena (photopsia) gain in relevance and may become key problems after modern cataract surgery. The purpose of this study is to evaluate potential influencing factors for these optical phenomena using ray tracing techniques in a model eye.Methods A schematic model eye was used for simulations with professional optic design software (ASAP). The crystalline lens was replaced by an intraocular lens implant. We varied the lens’ edge design (edge radius from 0.00 mm (0.05 mm) 0.15 mm), refractive index (1.55 and 1.46), axial and lateral position (each ±0.5 mm), as well as the pupil diameter (2.5, 3.5 and 4.5 mm). Retinal illuminance was simulated for a Ganzfeld perimeter sphere (d=300 mm, 250° field of view) with 107 rays emitting in a Lambertian distribution.Results Positive photopsia could be observed at the central and paracentral nasal visual field originating from total internal reflection at the lens’ optics edge, which becomes more intense with higher refractive index and smaller edge radius or larger peripheral thickness of the lens. Negative photopsia was seen at the far temporal visual field as a gap in illuminance originating by a gap between overlaying light pathways of primary image and direct path. Photopsia is less pronounced with larger pupil size and axial or lateral displacement of the lens.Conclusion Photopsia is not a new phenomenon in pseudophakic eyes, but with lenses with a high refractive index (smaller incision) and sharp optic edges (for prevention of secondary cataract) the intensity of artificial light phenomena and gaps photopsia might become the main reason for patient dissatisfaction after cataract surgery.

Dual–optic Accommodating IOL—A Review

This article reviews the design, development, objective accommodation data, and clinical results of the dual-optic accommodating IOL. The first-generation dual-optic accommodating IOL was designed to interact with the contraction and relaxation of the ciliary muscle to generate accommodation. The more recent aspheric version enhanced this technology to further improve the near benefit. The main advantage of the dual-optic accommodating IOL is the low incidence of problems with contrast, glare, and halos associated with multifocal IOLs. The main criticisms are the lower consistency of visual acuity at near distances and the lower refractive predictability. Newer IOL designs are bringing us closer to the ideal of providing patients with perfect high-quality vision at all distances. The dual-optic accommodating IOL has demonstrated to be a safe alternative to provide very good near and intermediate vision without sacrificing distance visual acuity or quality of vision.

High Resolution OCT Quantitative Analysis of the Space Between the IOL and the Posterior Capsule During the Early Cataract Postoperative Period

We quantitatively characterized the space between the IOL and the posterior capsule (IOL-PC space) during the early postphacoemulsification period, using high resolution optical coherence tomography (OCT). We recruited 30 eyes of 30 patients who underwent phacoemulsification and randomly divided them into two groups. Acrysof Natural IQ IOLs were implanted in one group (n = 15), and Adapt-AO IOLs were implanted into the other (n = 15). A custom-built OCT instrument was used to image the IOL-PC space at 1 day, 1 week, and 1 month after surgery. Slit-lamp examination and auto refraction were performed at each visit. The IOL-PC spaces in the IQ group were 0.72 ± 0.35, 0.40 ± 0.24, and 0.23 ± 0.16 mm(2) at 1 day, 1 week, and 1 month after surgery, respectively. At each of these times, the values for the AO group were significantly smaller (P < 0.001). Compared to 1 day after surgery, significant changes in the ACDs and refractive errors occurred up to 1 month postoperatively in the IQ group; however, changes in the ACD and refractive error were significant only at 1 week in the AO group. The decreases in IOL-PC space and in ACD during the early postoperative period were associated with a myopic shift. It appeared that the different IOL designs had a role in closure of the IOL-PC space. High resolution OCT was suitable for quantitative analysis of IOL-PC space. (ClinicalTrials.gov number, NCT01605812.).

What is important in present and future IOL materials &amp; design?

AbstractIOL progress has followed 2 main lines: optical performance,and materials/design. This talk reviews their impact and possible future trends.IOL optics evolved from spheric monofocal to aspheric (+optionally toric) to multifocal; from refractive to diffractive multifocality, currently with several choices regarding add, bi‐ vs trifocality, etc. Additionally a number of designs attempt to reproduce the lens accommodative mechanism. However,none of the available options truly restores the physiological accommodation of the youth. The main drive for the evolution of IOL materials and designs has been implantability through an ever‐decreasing incision width. While this may have created some compromises regarding materials and optical quality/stability, it seems unlikely that this process could revert. Next major issue is the prevention of PCO. Aspects as the posterior square edges and hydrophobic materials are widely assumed as useful to prevent PCO. However, a general proof is difficult due to the numerous factors involved (IOl &amp; non‐IOL) and the great variability of designs. IOL materials durability lags in a 3rd position of interest (apart from cases of IOL opacification) but is likely an emerging topic for the near future.

Customized Aspheric IOL Design by Raytracing through the Eye Containing Quadric Surfaces

Purpose: The purpose of the present study was to demonstrate a method of how to calculate intraocular lenses with a customized asphericity and how to apply this strategy to clinical examples in cases where biometric data of the cornea (front and back surface topography) as well as distances in the eye are known.Methods: (1) we demonstrated an algebraic method for tracing a bundle of rays through a schematic eye containing surfaces which can be represented by 2nd order surfaces (quadric surfaces), and (2) we introduced a strategy for customization of the lens’ back surface for compensating the optical path length differences of the rays from object to image in terms of a wave front correction while predefining the lens front surface.Results: The presented method was applied to three working examples: example 1 referred to a centered optical system with a spherical cornea (front and back surfaces) and a predefined spherical lens front surface, example 2 referred to a centered optical system with aspherical surfaces for the corneal front and back surfaces and a predefined spherical lens front surface, and example 3 referrred to a non-centered system with a decentered aspherical cornea (front and back surface), and a predefined spherical lens front surface. The parameterized ray intersection points with the lens back surface were optimized in terms of equalizing the ray path lengths and a quadric surface was fitted to these ray intersection points to characterize the customized lens. The fitting error, ray spot diagram, and the optical path length of the rays are provided.Conclusion: This simple calculation strategy may be the first step in developing individual aspherical lenses, which have the potential to fully compensate spherical aberrations based on individual measures of the eye.

Prevention of posterior capsule opacification by combination of arsenic trioxide and perfect capsule

Despite recent improvements in IOL design, posterior capsule opacification (PCO) remains a significant clinical problem after cataract surgery. The Perfect Capsule device (Milvella, Ltd., Epping, Australia) permits the introduction and subsequent removal of potentially toxic agents into the closed capsular bag. The present purpose was to detect the effectiveness of arsenic trioxide (As2O3) to cultured human lens cells and cells within the human capsular bag. All experiments were carried out with 2 minutes exposure to As2O3. Effect of As2O3 on FHL124 cells growth was tested by MTT. Changes in cell calcium levels induced by high concentration of As2O3 were measured by real-time fluorometric single-cell digital imaging techniques after Fura-2 incorporation. In vitro human capsular bags were also tested after a sham surgery was performed using the Perfect Capsule device to form a closed system. As2O3 (10, 30, 100, 300, 1000 µmol/L) were used with donor match-pairs treated with medium alone.(n = 3 in all cases).On-going observations were by phase-contrast microscopy. Cellular architecture was examined by fluorescence cytochemistry. As2O3 of 100 µmol/L and above inhibited the growth of FHL 124 cells in a dose-dependent manner with 2 minutes exposure (t = 5.217, P < 0.01, IC(50) is 130 µmol/L) As2O3 depleted the calcium store and consequently lead to a loss of calcium signaling.Moreover, 1 × 10(4) µmol/L As2O3 had a moderate effect on the calcium influx pathway, inhibition on the amplitude and rapidity is (43.24 ± 2.98)% (t = 3.134, P < 0.01) and (46.27 ± 6.01)% (t = 3.521, P < 0.01), respectively. No cell left in the vitro human capsular bags after being treated with 1 × 10(4) µmol/L As2O3. As2O3 can eliminate the human lens epithelium cells remained in the capsular bag in cataract surgery, which may help to prevent PCO. The application of As2O3 to cells within the capsular bag for a 2 minute window using the Perfect Capsule system predicts this compound will have therapeutic benefit to humans in vivo.

Non‐surgical strategies for PCO prevention

Abstract Purpose Surgical approaches and IOL design have gone some way to reduce the rate of PCO progression. Despite these efforts PCO remains a common and important problem which diminishes the visual quality of patients and is a major financial burden on healthcare providers. If we are to effectively respond to the problem of PCO then a biological solution has to be adopted to reduce/prevent formation of light scattering changes. Methods Methods have been employed to investigate PCO development, which include in vitro cell culture and capsular bag models; in vivo animal models and post‐mortem analysis. These have greatly aided our understanding of PCO. Results A number of basic approaches have been identified to prevent PCO. 1) To kill the entire lens epithelial population. This will require a pharmacological agent, therefore delivery of this drug needs to be localised to the target cells, but have limited access to non‐target cells; closed capsular bag systems such as perfect capsule provides opportunity to achieve this aim. 2) Maintenance of a cell monolayer on the posterior capsule. In particular the role of TGFβ has been investigated, which is known to cause matrix deformation. Disruption of TGFβ signalling pathways can suppress matrix deformation and thus reduce light scatter. 3) Recreation of a lens is the ultimate solution. While it has been shown that lens fibre differentiation can be promoted in animal systems, perfect formation of the lens is not achieved and the protein density is typically low relative to the native lens. Conclusion Strategies to prevent PCO are being actively developed, which will are greatly aided by improved drug delivery systems. The development of biological/pharmacological approaches in concert with improved surgical methods and IOL designs should yield benefit to patients. Commercial interest

Effects of 400 nm, 420 nm, and 435.8 nm radiations on cultured human retinal pigment epithelial cells

The present study demonstrates narrowband short-wavelengths radiation- (400, 420, and 435.8 nm) induced cellular damage of cultured human retinal pigment epithelial cells using in vitro biological assays to determine wavelengths that are responsible for photochemical lesions of the retina. This work involved the exposure of retinal pigment epithelial (RPE) cells (ARPE-19) to narrowband light of three different wavelengths (400, 420, and 435.8 nm) using a xenon arc lamp and interference filters. Cellular viability, mitochondrial distribution, and nucleic acid (both DNA and RNA) damage were quantified after various energy levels of exposure, using the Alamar blue assay, and confocal laser scanning microscopy with two fluorescent stains (Rhodamine 123 and Acridine Orange). The results clearly show that 400 nm light radiation can cause significant dose-dependent decreases in RPE cell viability as well as degradations of DNA/RNA and mitochondria in RPE cells, while 420 and 435.8 nm light radiation cause no cellular damage. While further evaluations may be needed to assess specificity and confounding factors of these assessment tools, the results may be a matter for consideration in future IOL design efforts.

Bag-in-the-lens: First pathological analysis of a human eye obtained postmortem

We analyzed an enucleated eye obtained postmortem from an 86-year-old donor who had been implanted with a hydrophilic acrylic bag-in-the-lens 4 months earlier. To our knowledge, this is the first donor eye implanted with this design to undergo pathological analysis. High-frequency ultrasound showed a well-centered IOL, fixated at the level of the capsular bag. Gross and light microscopic analyses of the eye showed that if anterior and posterior capsule openings are well stretched around the optic of this IOL design, proliferative/regenerative material is potentially confined to the intercapsular space of the capsular bag remnant outside the optic rim.

Clinical use of multifocal and focus shift IOLs

Abstract Purpose To compare the clinical experience with multifocal and focus shift IOLs in Austria, Germany and Spain. Methods We give a summary of published and unpublished data, reviews and meta‐analyses. Main outcome measures are uncorrected distance and near visual acuity, and reading speed under different light conditions as well as subjective patient satisfaction and spectacle independence. The focus will be on ReStor, ReZoom and Technis IOLs in the multifocal group, and ICU, BioComFold, AT‐45 Crystalens in the focus shift group. Results Multifocal IOLs can provide functional intermediate vision in bright light; under dim light the results vary depending on the IOL design. Hybrid design of the refractive‐diffractive IOL can reduce the increased optical aberrations induced by purely refractive multifocal IOLs. Aspheric apodized diffractive IOLs can reduce stray light artefacts and can enhance distance vision performance for large pupils. Focus shift IOLs result in a moderate to no improvement for uncorrected near visual acuity and minor or no forward movement, on average corresponding to less than 0.5 diopters. Conclusion Multifocal IOLs provide pseudo‐accommodation and their optical quality has improved due to new design developments. Focus shift IOLs accommodate only by a minor amount abd give some pseudo‐accommodation by mechanisms not clearly understood.

Intraocular lens features that affect PCO

Abstract Purpose To review IOL features that affect PCO Methods Review of clinical PCO studies using retroillumination imaging and objective quantification of PCO following cataract surgery and laboratory EM studies of IOL profile Results The optic diameter, haptic design and IOL material all affect PCO performance but the optic edge profile is the most important. Electron microscopy shows IOL edge is of variable profile in so called 'square edge' IOLs and this can be explained by the inevitable interrelationship of the limitations that material imposes on engineering, early closure of the capsular bag around the IOL seems to be important in preventing leakage of LECs into the retro lenticular space soon after surgery that later proliferate and form clinical PCO Conclusion PCO has a multifactorial pathogenesis. Improved IOL design can limit but does not prevent PCO Commercial interest

Capsular block syndrome after cataract surgery: Clinical analysis and classification

To study the incidence of and risk factors for postoperative capsular block syndrome (CBS) and propose a new classification based on etiology. Department of Ophthalmology, Kyungpook National University Hospital, Daegu, Republic of Korea. Charts of 1100 eyes of 990 patients who had phacoemulsification and posterior chamber intraocular lens (PC IOL) implantation between January 2003 and June 2006 were retrospectively reviewed. Demographic data, axial length (AL), type of PC IOL implanted, and intraoperative ophthalmic viscosurgical devices (OVDs) were recorded. The cases of postoperative CBS were collected and the characteristic clinical findings evaluated. There were 8 cases (7 patients) of postoperative CBS (incidence 0.73%). Longer AL (>or=25.0 mm) was a risk factor for postoperative CBS (P= .008; odds ratio [OR], 5.75, 95% confidence interval [CI], 1.353-24.413). The PC IOL with 4 haptics (Akreos Adapt, Bausch & Lomb) was also associated with an increased incidence of postoperative CBS (P= .001; OR, 7.388; 95% CI, 1.751-31.168). The CBS was classified as noncellular, inflammatory, or fibrotic according to the clinical characteristics. Although postoperative CBS was a rare complication after cataract surgery, AL and PC IOL design had a significant influence on the incidence. Evaluation of clinical characteristics showed 3 distinct types of CBS.

Clinical Results of Rollable IOL Implantation After Bimanual Microincision Phacoemulsification

Purpose: To retrospectively evaluate the clinical results of insertion of a hydrophilic acrylic plate posterior chamber intraocular lens (ThinOptX) after bimanual microincision phacoemulsification. Methods: Thirty-four eyes of 30 patients who underwent bimanual phacoemulsification and ThinOptX implantation through a 2.0 mm incision between July 2004 and May 2006 were followed-up for more than 12 months. We examined best corrected visual acuity (BCVA), refractive errors, corneal endothelial cell density, halo and contrast sensitivity, posterior capsule opacification (PCO), and intraoperative and postoperative complications. Results: The preoperative mean logMAR BCVA was 0.43±0.24, and the postoperative BCVA was 0.04±0.09 after 6 months and 0.14±0.12 after 12 months. The preoperative corneal endothelial cell density was 2562±347.90 cells/mm2, and decreased to 2241±294.88 (cells/mm2) at 12 months postoperative. Postoperative contrast sensitivity at 6 months was increased in both photopic and mesopic condition. Halo was noted in all examined eyes. A PCO of 29% was evaluated at 6 months postoperative and a PCO of 52% was evaluated at 12 months postoperative. Conclusions: Bimanual phacoemulsification and ThinOptX implantation through a 2.0 mm incision resulted in good initial visual outcome and correction of refractive errors. However, problems such as halo and PCO associated with IOL design were noted. Therefore, further evaluation and correction of the IOL are needed.

Clinical Ocular Wavefront Analyzers

To provide a summary of the methods used by clinical wavefront analyzers and their historical, current, and future applications. Review of the literature and authors' experience with the various devices. A wide range of clinical wavefront aberrometers, which use different principles, are available to clinicians and researchers. Applications of wavefront analyzers in vision sciences range from assessment of refractive error, refractive surgery planning, evaluation of outcomes, optimization of contact lenses and IOL designs, evaluation of pathology relating to optical performance of the eye, and evaluation of accommodation alterations.

Lens Cell Survival after Exposure to Stress in the Closed Capsular Bag

Despite recent improvements in IOL design posterior capsule opacification (PCO) remains a significant clinical problem after cataract surgery. The Perfect Capsule device (Milvella, Ltd., Epping, Australia) permits the introduction and subsequent removal of potentially toxic agents into the closed capsular bag. The present purpose was to compare the relative effectiveness of exposing cells within the human capsular bag with a range of stresses with clinical potential and to compare the response to the same agents when applied to rabbit capsular bags and to cultured human lens cells. Human capsular bags were prepared from donor eyes and sealed with the Perfect Capsule device. Distilled water, 3 M NaCl, 250 microg/mL, 25 mg/mL 5-fluorouracil and 100 microM thapsigargin (Tg) were introduced for 2 minutes. The bags were then perfused with Eagle's minimum essential medium (EMEM) and an IOL inserted before the bags were dissected and pinned to the base of plastic culture dishes. The bags were maintained in EMEM for 28 days and phase images were acquired throughout. Rabbit eyes were prepared and cultured in a similar manner, although tests were limited to 5-FU (25 mg/mL) and Tg (30-300 microM). FHL124 cells were cultured on plastic (EMEM supplemented with 5% FCS), and serum was removed for 24 hours before exposure to the same agents as human bags. Cell survival was assessed by quantifying Coomassie blue staining after 4 days. Initially, NaCl induced by far the most obvious signs of cell death, especially of anterior cells, followed by 5-FU>water>Tg. However, by 2 weeks, cell death became more apparent in the Tg-exposed bags, and, at the end of 4 weeks, there were no cells surviving. Cells on the posterior capsule were confluent in water-exposed bags (similar to unexposed controls), whereas after NaCl exposure, coverage was incomplete but greater than after 5-FU. In the rabbit bags, exposure to 25 mg/mL 5-FU totally eliminated cells, but 100 microM Tg was ineffective. At the end of a 4-day culture of FHL124 cells exposed for 2 minutes to NaCl, 5-FU or Tg, there were no cells surviving, whereas there was 50% cell survival compared with control cells after water treatment. Tissue-cultured human lens cells are much more sensitive to short-term hyperosmotic than hyposmotic stress, with a rapid onset of cell death of cultured cells exposed to 3 M NaCl. This finding was confirmed in human capsular bags although adherent fibers appear to offer additional protection to 5-FU which can be overcome by the very hydrophobic Tg. The application of the Perfect Capsule system in concert with thapsigargin provides a promising means of preventing PCO.

053 Systèmes mécatroniques pour restaurer l‘accommodation

To date, mechanical IOL concepts for so-called accommodative lenses have a very limited accommodative ability. Implantable mechatronic microsystems are new approaches to restore these accommodative ability of the human eye. Currently different active and passive designs for example dual-optic, triple-optic approach or IOL designs using cubic optical elements (Alvarez lenses) are in investigation with regard to their appropriateness. These new concepts are very promising and in an early experimental state. But long-ranging, it seems that mechatronic systems are to be able to achieve the expectations. This talk will give a review about new developments, own research results and experiences on this very exciting field of research.

Reply : Another view of neodymium:YAG capsulotomy

We thank Werblin and Krider for their comments regarding our article. Their critique addresses not the methods or results of our study but solely a statement in the introduction section that Nd:YAG laser capsulotomy may increase the rate of retinal detachment (RD) and also the cost of cataract treatment. In this context, we would like to point out that our article does not focus on the negative aspects of Nd:YAG laser capsulotomy, but instead on the significantly lower rate of PCO and capsulotomies in eyes with sharp-edged acrylic IOLs compared with the rate in eyes with round-edged IOLs. Thus, we did not mention the (undisputed) advantages of secondary capsulotomy. Of course, it is also common practice at our department to treat patients with PCO-induced loss of vision by Nd:YAG laser capsulotomy, as we did in the course of the reported study. A possibly higher rate of RD and other complications following capsulotomy is controversial and has been discussed in the literature.1–5 Werblin's personal data on RD following capsulotomy, even though not gathered in a prospective fashion, seem to speak in favor of the safety of this procedure. However, the need for Nd:YAG laser capsulotomy causes additional costs for the health care system, and these costs could be reduced. We do not agree that methods trying to prevent PCO are generally more expensive than the treatment of PCO itself. The introduction of the sharp (posterior)-edged optic has led to a significant reduction in PCO and capsulotomy rates. To our knowledge, the production costs for sharp-edged IOLs are not higher than those for round-edged models. Besides, sharp-edged IOLs do not require more “sophisticated” surgery. We believe that MDs need to be concerned about the rising costs of health care and should be interested in making the system work as efficiently as possible to guarantee our patients a high quality of care in the future, because the financial resources are finite. Reimbursement is a separate issue and it should not dictate our practice style. Werblin and Krider state that it might be cheaper to implant PMMA IOLs and to eventually perform Nd:YAG laser capsulotomies than to spend more money on developing new IOLs and other materials to prevent PCO. However, PMMA lenses can also be produced with sharp optic edges at no additional cost, which also leads to a significant reduction in the capsulotomy rate.6 The same holds true for silicone lenses.7 In general, we believe that development should continue; otherwise, we will be confronted with a standstill of research altogether. To conclude, a sharp posterior IOL optic significantly decreases the incidence of PCO at no additional cost compared with a round optic. This modification reduces the discomfort and transient reduction in quality of life caused by PCO and a subsequent capsulotomy for many patients. The purpose of our prospective randomized study was to show that this significant and permanent PCO-inhibiting effect was caused by a simple modification in IOL design.

Neue Methoden der Nachstarprävention

Even though tremendous advances have been made especially during the last 10-15 years in terms of surgical techniques and improvement of implant technology, posterior capsule opacification (PCO) still remains a serious long-term complication. New clinical and laboratory studies (especially of autopsy eyes) have improved our understanding of how IOL design and material influence PCO. Sharp edge optic designs of IOLs of various materials have been shown to significantly reduce secondary cataract. The application of pharmacological substances selectively into the capsular bag is now possible due to the development of the PerfectCapsule System for vacuum-sealed capsule irrigation. Major advances in other areas of biotechnology and immunology including gene therapeutic methods offer totally new approaches for the future in the elimination of lens epithelium cells from the capsular bag. This survey gives an update on current and future means and trends to reduce or prevent PCO formation.

Anterior chamber and sutured posterior chamber intraocular lenses in eyes with poor capsular support

To compare the clinical outcomes and complications of patients who had surgical placement of anterior chamber (AC IOLs) and sutured posterior chamber intraocular lenses (PC IOLs) after cataract surgery resulting in poor capsular support. Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida. A retrospective interventional comparative case series of 181 eyes of 181 patients that had implantation of an intraocular lens with inadequate capsular support was conducted. A chart review of all patients that had implantation of AC IOLs or sutured PC IOLs at a tertiary care eye hospital between 1995 and 2001 was conducted. Outcome measures included final best-corrected visual acuity, spherical equivalent, and postoperative complications (pseudophakic bullous keratopathy, elevated intraocular pressure [IOP] inflammation, retinal detachment, suture erosion, cystoid macular edema). Of 702 charts reviewed, 181 were found to fit inclusion and exclusion criteria. The postoperative complication risk ratio was 0.80 (95% confidence interval [CI]: 0.52-1.23) for AC IOLs compared with PC IOLs. The most common complication experienced by patients having implantation of either lens type was elevated IOP (AC IOL: 38%; PC IOL: 42%). The incidence of other complications was similar between the groups. Best-corrected visual acuity was similar; however, final spherical equivalent trended toward more myopic values in the PC IOL group (-0.82 +/- 1.67 for AC IOL versus -1.32 +/- 2.12 for PC IOL). The findings suggest that no significant differences in outcome exist when comparing AC IOLs to sutured PC IOLs in complicated cataract extraction with poor capsular support. Recent advances in AC IOL design have yielded lenses that provide a safe, effective alternative to sutured PC IOLs.