Posterior capsule opacification after implantation of a hydrophilic or a hydrophobic acrylic intraocular lens: one-year follow-up

Intraocular lens selection in diabetic patients: How to increase the odds for success

The incidence of cataracts is significantly higher in diabetic individuals, particularly in younger age groups, with rates quadrupled in those under 65 and doubled in those over 65 compared to non-diabetics. Cataract surgery in diabetic patients poses many challenges: Poor epithelial healing, decreased corneal sensitivity, increased central corneal thickness, decreased endothelial cell count, variable topography, poor pupillary dilatation, anterior capsular phimosis, posterior capsular opacification (PCO), chances of progression of diabetic retinopathy (DR), zonular weakness, and vitreous prolapse and diabetic macular edema. Selection of an appropriate intraocular lens (IOL) is crucial for visual rehabilitation and monitoring DR. The choice of IOL in diabetic cataract patients is a challenging scenario. Square-edge IOLs are favored for their capacity to mitigate PCO, whereas hydrophilic counterparts may incur calcification in the setting of proliferative DR. The advisability of premium IOLs for achieving spectacle independence warrants judicious evaluation, particularly in the presence of advanced retinopathy. Optimal IOL placement within the capsular bag is advocated to minimize postoperative complications. Rigorous preoperative assessment and informed patient counseling regarding IOL options are indispensable for optimizing surgical outcomes. This review article covers various aspects regarding the choice of IOLs in different case scenarios and complications in the diabetic population.

Evaluation of posterior capsular opacification and neodymium-doped yttrium aluminum garnet capsulotomy rates in patients with hydrophilic intraocular lens implantation with and without ocular viscoelastic device

Purpose

To study the effect of intraocular lens (IOL) implantation with and without ocular viscoelastic device (OVD) on posterior capsular opacification (PCO) in eyes with phacoemulsification.

Methods

This prospective, comparative, and randomized case series included 70 patients (140 eyes) with senile cataracts scheduled for phacoemulsification and IOL implantation in a tertiary eye c are center. One eye of each patient was randomized to one of the two groups, namely, control and OVD. After phacoemulsification, the IOL was placed in the capsular bag under balanced salt solution (BSS) in the control group, whereas the IOL was placed under OVD in the OVD group. PCO was analyzed by an independent observer at 6, 12, and 18 months under slit-lamp illumination.

Results

The mean age of the participants in the two groups was 61.2 (±9.9) years. Of the total participants, 68 (48.5%) were men and 72 (51.5%) were women. The mean keratometry (K1, K2) values of the OVD (44.26 ± 1.43, 44.93 ± 1.66) and control (44.51 ± 1.74, 44.69 ± 1.49) groups were similar. The mean IOL powers of the control and OVD groups were 21.25 (±1.94) and 21.53 (±1.86), respectively (P = 0.463). The mean best-corrected visual acuity (BCVA) of the control group at 6-, 12-, and 18-month follow-ups were 0.622 (±0.253), 0.315 (±0.203), and 0.063 (±0.163), respectively, whereas those of the OVD group were 0.592 (±0.253), 0.336 (±0.169), and 0.066 (±0.118), respectively (P = 0.922). None of the patients had postoperative raised intraocular pressure (IOP), uveitis, or endophthalmitis. Three and four eyes in the control and OVD groups, respectively, required neodymium-doped yttrium aluminum garnet (ND: YAG) capsulotomy at study termination (P = 0.999).

Conclusion

The hydroimplantation technique of the placement of hydrophilic IOL did not reduce the PCO rate in the 18-month follow-up period. The ND: YAG capsulotomy rate did not differ between the groups.

Cataract Surgery Considerations for Diabetic Patients

PURPOSE OF REVIEW

Given the epidemiology and demographic trends of diabetes mellitus and cataracts, ophthalmologists are likely to encounter patients with both comorbidities at an increasing frequency. Patients with diabetes represent a higher risk population than healthy patients for cataract surgery. In this review, we discuss key risks and risk-mitigation practices when performing cataract surgery on these patients.

RECENT FINDINGS

Patients with diabetes continue to represent a high-risk surgical population: Nagar et al. suggest a dose-dependent relationship may exist between number of intravitreal injections and likelihood of posterior capsular rupture. However, novel treatments are improving outcomes for patients with diabetes. Several studies have reported intracameral phenylephrine/ketorolac may reduce the incidence of post-operative cystoid macular edema while others have discussed the efficacy of pre-treatment and post-treatment with intravitreal bevacizumab on improving cataract surgery outcomes in patients with diabetic retinopathy. Pre-operatively, ophthalmologists should perform an enhanced evaluation, consider timing and lens selection decisions, and complete any appropriate pre-operative treatment. Peri-operatively, surgeons should be aware of pupillary dilation adjustments, combination surgery options, and potential complications. Post-operatively, clinicians should address pseudophakic cystoid macular edema, diabetic macular edema, diabetic retinopathy, and posterior capsular opacification.

Polymeric Materials for Eye Surface and Intraocular Applications

Ocular applications of polymeric materials have been widely investigated for medical diagnostics, treatment, and vision improvement. The human eye is a vital organ that connects us to the outside world so when the eye is injured, infected, or impaired, it needs immediate medical treatment to maintain clear vision and quality of life. Moreover, several essential parts of the eye lose their functions upon aging, causing diminished vision. Modern polymer science and polymeric materials offer various alternatives, such as corneal and scleral implants, artificial ocular lenses, and vitreous substitutes, to replace the damaged parts of the eye. In addition to the use of polymers for medical treatment, polymeric contact lenses can provide not only vision correction, but they can also be used as wearable electronics. In this Review, we highlight the evolution of polymeric materials for specific ocular applications such as intraocular lenses and current state-of-the-art polymeric systems with unique properties for contact lens, corneal, scleral, and vitreous body applications. We organize this Review paper by following the path of light as it travels through the eye. Starting from the outside of the eye (contact lenses), we move onto the eye's surface (cornea and sclera) and conclude with intraocular applications (intraocular lens and vitreous body) of mostly synthetic polymers and several biopolymers. Initially, we briefly describe the anatomy and physiology of the eye as a reminder of the eye parts and their functions. The rest of the Review provides an overview of recent advancements in next-generation contact lenses and contact lens sensors, corneal and scleral implants, solid and injectable intraocular lenses, and artificial vitreous body. Current limitations for future improvements are also briefly discussed.

Intraocular Lenses: Overview of Designs, Materials, and Pathophysiologic Features

This article provides an overview of intraocular lenses (IOLs) currently used in cataract surgery. Aspects presented include design features related to IOL construction and sites of fixation; optic, filter, and haptic materials; as well as pathophysiologic features of uveal biocompatibility, capsular biocompatibility, and postoperative IOL opacification. This overview also includes supplementary (add-on; piggyback) lenses implanted in eyes that are already pseudophakic and considerations on IOLs used in the pediatric population. Different IOLs are made available to surgeons each year, including lenses with increasingly complex design characteristics owing to advancements in manufacturing and surgical techniques.

Anti-inflammatory Medication After Cataract Surgery and Posterior Capsular Opacification

PURPOSE

To assess the role of anti-inflammatory medication following cataract surgery on the formation of posterior capsular opacification.

DESIGN

Cohort study.

METHODS

A retrospective registry analysis of 25,818 consecutive patients who underwent cataract surgery between the years 2014 and 2018 at Helsinki University Hospital in Finland. Nd:YAG laser capsulotomy rates were compared between patients treated postoperatively with topical steroids, nonsteroidal anti-inflammatory medications (NSAIDs), or their combination. Kaplan-Meier and Cox regression analyses were used. A single eye of each patient was included. Main outcomes were confirmed against a second independent dataset.

RESULTS

A total of 13,368 patients were included in the analysis, with a mean age of 73.2 ± 9.7 years; 61.7% were female. Pseudoexfoliation was noted in 10.1% of cases. The mean follow-up time was 22.8 ± 15.7 months. Patients were treated with steroid monotherapy (28.9% of cases), NSAID monotherapy (62.2%), or a combination of both (8.9%). Treatment with steroids resulted in significantly lower Nd:YAG capsulotomy rates compared to NSAIDs (hazard ratio [HR] 0.76, 95% confidence interval [CI] 0.62-0.93, P = .009). Treatment with combination therapy of steroids and NSAIDs showed no added benefit over steroid monotherapy (HR 1.11, 95% CI 0.68-1.80, P = .674). Cox regression analysis adjusted for patients' age, sex, pseudoexfoliation, and risk stratification remained significantly predictive for lower capsulotomy rates with steroid treatment over NSAIDs (HR 0.70, 95% CI 0.52-0.88, P = .001).

CONCLUSIONS

Postoperative treatment with steroids among patients undergoing uncomplicated cataract surgery was associated with lower rates of clinically significant posterior capsule opacification compared to treatment with NSAIDs alone. Combination therapy of steroids and NSAIDs had no added benefit over steroids alone.

Budget impact analysis of lens material on the posterior capsule opacification (PCO) as a complication after the cataract surgery

Background

Over 300,000 cataract operations are performed in Poland every year, and the most common, late complication of cataract removal surgery is posterior capsule opacification (PCO). The risk of PCO depends on the lens material. Hydrophobic acrylic lenses cause PCO less frequently as lymphatic endothelial cells show lower affinity for the surface of the lens made of silicone. The objective of this study is to assess the economic impact of using hydrophobic acrylic lenses compared to using hydrophilic acrylic lenses for cataract treatment in the Polish inpatient and outpatient settings.

Methods

A budget impact analysis (BIA) compared the economic outcomes associated with using hydrophobic acrylic lenses versus using hydrophilic lenses for patients undergoing cataract surgery. The BIA predicted annual expenses in the following scenarios: performing Nd:YAG to treat PCO within 2 and 3 years after implantation of hydrophobic or hydrophilic acrylic lenses for different lens structure. Data used to assess the frequency of PCO was determined in systematic literature review. Costs of current and predicted interventions were estimated based on average data from 19 Polish hospitals. Prices of health services were taken from official public tariff lists.

Results

The use of a hydrophobic lens significantly limits the number of complications after cataract surgery relative to a hydrophilic lens. As hydrophobic lenses have a higher unit price their use increases the cost of treatment which currently is not reflected by adequate difference in price of the service. Total annual National Health Fund (NHF) expenses for 3-year follow-up model range from 139.1 million EUR to 143.1 million EUR depending on the lens structure, due to the cost of complications.

Conclusions

BIA indicates the possibility of introducing surcharge for the use of hydrophobic lenses, which could increase the frequency of their use and reduce the number of complications after cataract surgery. It was estimated that total NHF expenses reach the minimum value for the surcharge at the level of 9 EUR. The surcharge of 14 EUR is the maximum value that does not increase the initial NHF expenses.

Rotation versus non-rotation of intraocular lens for prevention of posterior capsular opacification

Purpose:

To study the effect of rotation of intraocular lens (IOL) on posterior capsular opacification (PCO) in eyes with phacoemulsification.

Methods:

This was a prospective, comparative, randomized case series. One eye of each patient was randomized to one of two groups. The 360-degree rotation of IOL was carried out after its placement in the capsular bag (rotation group). The control group had no rotation of IOL. PCO was analyzed by an independent observer on EPCO computer analysis system at 6, 12, 24, and 36 months.

Results:

The study included 50 patients (100 eyes) with senile cataracts scheduled for phacoemulsification and IOL implantation. The median age in 2 groups was 66 years. 25% quartile age in both the group was 62 years (P = 0.06). There were 30 males, and 20 females. The median PCO score at 6, 12 and 24 months was significantly low in the rotation group (0.15, 0.13, 0.22) compared to the control group (0.22, 0.23, 0.25). There was no significant difference in PCO score between the two groups from 24-36 months. The median PCO score at 36 months was 0.2 in both the groups. At the end of three years, 4 eyes (8%) in the rotation group, and 10 eyes (20%) in the control group needed Nd:YAG capsulotomy (P = 0.04).

Conclusion:

Rotation of IOL in the capsular bag decreases PCO and Nd:YAG capsulotomy rate.

Cataract in diabetes mellitus

Diabetes mellitus (DM) is a chronic systemic disease that has increases in prevalence over time. DM can affect all ocular structures, with cataract being the most common ocular complication. Cataract is the leading cause of blindness worldwide. Due to several mechanisms, there is an increased incidence of cataract formation in the diabetic population. Advancements in technology have now made cataract surgery a common and safe procedure. However, the diabetic population is still at risk of vision-threatening complications, such as diabetic macular edema (ME), postoperative ME, diabetic retinopathy progression, and posterior capsular opacification.

Incidence of posterior capsular opacification requiring Nd:YAG capsulotomy after cataract surgery and implantation of enVista® MX60 IOL

PURPOSE

To evaluate incidence of posterior capsule opacification requiring Nd:YAG capsulotomy over 3 years in a large series of eyes implanted with the enVista^® MX60 Intraocular Lens (IOL).

METHODS

A university-based, single-center, observational study of patients' medical records was conducted. Uneventful cataract surgery patients with in-the-bag implantations of the enVista^® MX60 IOL with a minimum of 24 months follow-up were included in the study. Exclusion criteria were insufficient follow-up (<24 months), intraoperative complications and combined surgery. The primary outcome measure was rate of YAG laser capsulotomy, while secondary outcome measures were time to YAG laser capsulotomy and rate of glistenings.

RESULTS

A total of 245 eyes of 143 patients received the MX60 IOL and were followed in the same center. Of these, 226 eyes were included in the study. Mean age was 80.7±8.3 years and M/F ratio was 42/101 (29.4/70.6%). The mean preoperative distance (logMAR) visual acuity was 0.67±0.5, while postoperatively it was 0.31±0.5 and 0.32±0.5 at the last visit. The Mean±SD follow-up time (min-max) was 35.2±7.2, (24-48.4) months. The incidence of Nd:YAG capsulotomy over 3 years was 5/226 (2.2%). Average time between surgery and Nd:YAG capsulotomy was 32.17 months. Univariate analysis of age, gender, presence of comorbidity and baseline visual acuity found no predictive factors for capsulotomy. No glistenings were reported at any postoperative visit.

CONCLUSION

The three-year cumulative incidence of PCO requiring Nd:YAG laser capsulotomy was 2.2% for the enVista^® MX-60 IOL, with no glistenings observed during follow-up. This low rate confirms the excellent safety profile of this IOL.

A meta-analysis of Nd:YAG capsulotomy rates for two hydrophobic intraocular lens materials

Purpose

The purpose of this study is to estimate and compare neodymium-doped yttrium aluminum garnet (Nd:YAG) capsulotomy rates for AcrySof ^® and Clareon^® intraocular lens (IOL) materials using historical data from the medical literature and Alcon-sponsored clinical studies.

Methods

Clinical trials that involved the implantation of AcrySof or Clareon monofocal IOLs in subjects with cataract or presbyopia were extracted from the literature and a company repository of clinical studies. The study duration, number of eyes, and cumulative percent of Nd:YAGs for posterior capsule opacification were extracted. Bayesian random effects meta-analyses were conducted to estimate and compare outcomes for the 2 different IOL materials.

Results

A Bayesian random effects, meta-analysis was performed that combined a literature review of published AcrySof Nd:YAG posterior capsulotomy rates and Nd:YAG rates observed in Alcon-sponsored clinical studies of AcrySof and Clareon. Sixteen Alcon studies contained Nd:YAG data suitable for meta-analysis. Three of these Alcon studies contained results for the Clareon material (2 one-year studies, and 1 three-year study). The literature review included 50 papers from 1998 to 2015. In combination, 30,891 eyes were available for analysis and 2040 Nd:YAG procedures were reported in studies with a follow-up duration ranging in length from 4 months to 10 years. The overall probability of performing a Nd:YAG capsulotomy within a year of implant for AcrySof was 1.44% (1.11% to 1.83%) and 0.62% (0.21% to 1.38%) for Clareon. There was small improvement in the probability of Nd:YAG within a year of implant for Clareon lenses of about 0.82% with a 95% credible interval of (0.07% to 1.36%) at 1 year. Results were similar for incidence rates per 100 surgeries in a year: 0.62 (0.21 to 1.40) for Clareon, 1.46 (1.12 to 1.87) for AcrySof, and the difference was 0.84 (0.07 to 1.39) favoring Clareon. At 3 years, the overall probability of performing a Nd:YAG capsulotomy for AcrySof was 4.19% (3.24% to 5.30%) compared with only 1.82% (0.63% to 4.02%) for Clareon.

Conclusion

A meta-analysis of Clareon multi-piece and single-piece clinical data predicts that the cumulative Clareon Nd:YAG probability will be ≤ AcrySof by 2.37% (0.18% to 3.91%) at 3 years. The results indicate that Clareon is likely to perform as well as, and possibly better than, AcrySof in terms of Nd:YAG capsulotomy rates.

Biomaterial Influence on Intraocular Lens Performance: An Overview

There is strong evidence that the IOL material is the factor having the greatest impact on posterior capsule opacification (PCO), anterior capsule opacification (ACO) development, and glistening formation after cataract surgery, even though there are other IOL features—such as haptic material and design and edge and optic design—that also have some influence. We reviewed the published literature describing the adverse events that are mainly related to the intraocular lens (IOL) material, such as PCO, ACO, and the subsequent capsule contraction, as well as glistening formation. The adverse events presented in this overview are the most common ones in clinical practice, and therefore, they are generally included in the clinical protocols for IOL evaluation.

Long-term results of trypan blue dye irrigation in the capsular bag to prevent posterior capsule opacification: A randomized trial

Purpose:

To study the effect of capsular bag irrigation of trypan blue dye (0.06%) on posterior capsular opacification (PCO) in eyes undergoing phacoemulsification.

Methods:

This was a randomized, trial conducted at a tertiary eye care center in central India. The study included 50 patients (100 eyes) with senile cataracts who were scheduled for phacoemulsification and intraocular lens (IOL) implantation and were willing to undergo bilateral cataract surgery. One eye of each patient was randomized to one of two groups. The dye group received 0.2 ml of trypan blue injected in the capsular bag after cortical cleanup under air. The control group (other eye of the same patient) received 0.2 ml of balanced salt solution injected in a similar manner. PCO in the central 3 mm area of IOL optic was analyzed by a masked observer using an evaluation of PCO software computer analysis system at 6, 12, 24, and 36 months.

Results:

The average age of patients was 62.05 ± 6.22 in the dye group and 64.92 ± 7.16 years in the control group. The mean PCO score at 6 months was significantly lower in the dye group (0.10 ± 0.15) than in the control group (0.22 ± 0.30). There were no significant differences in the PCO scores between the two groups from 12 to 36 months. At the end of 3 years, eight eyes in the dye group and seven in the control group required YAG capsulotomy (P = 0.21).

Conclusion:

Capsular bag irrigation of trypan blue dye decreased the PCO score at 6 months, but it had no effect at 36 months.

Comparison of hydrophobic and hydrophilic intraocular lens in preventing posterior capsule opacification after cataract surgery: An updated meta-analysis

BACKGROUND

Posterior capsular opacification (PCO) is a common long-term complication of cataract surgery. Intraocular lens design and material have been implicated in influencing the development of PCO. This study evaluated the association of hydrophobic and hydrophilic intraocular lenses on preventing PCO.

METHODS

Medline, Cochrane, EMBASE, and Google Scholar databases were searched until August 3, 2016, using the following search terms: cataract, posterior capsule opacification, and intraocular lens. Eligible studies included randomized controlled trials (RCTs), retrospective, and cohort studies.

RESULTS

Eleven studies were included in the study with a total of 889 eyes/patients. The overall analysis revealed that hydrophobic intraocular lenses were associated with lower Nd:YAG laser capsulotomy rates than hydrophilic lenses [odds ratio (OR) = 0.38, 95% confidence interval (95% CI) = 0.16-0.91, P = .029]. Hydrophobic intraocular lenses were also associated with lower subjective PCO score (diff. in means: -1.32, 95% CI = -2.39 to -0.25, P = .015) and estimated PCO score (diff. in means: -2.23; 95% CI, -3.80 to -0.68, P = .005) as compared with hydrophilic lenses. Objective PCO score was similar between lens types. (diff. in means: -0.075; 95% CI, -0.18 to 0.035; P = .182). Pooled analysis found that visual acuity was similar between hydrophobic and hydrophilic intraocular lenses (diff. in means: -0.016; 95% CI, -0.041 to 0.009, P = .208).

CONCLUSION

In general, PCO scores and the rate of Nd:YAG laser capsulotomy were influenced by intraocular lens biomaterial. Lens made of hydrophobic biomaterial were overall superior in lowering the PCO score and the Nd:YAG laser capsulotomy rate, but not visual acuity.

Glistenings, anterior/posterior capsular opacification and incidence of Nd:YAG laser treatments with two aspheric hydrophobic acrylic intraocular lenses - a long-term intra-individual study

PURPOSE

To compare two hydrophobic acrylic intraocular lenses (IOLs) regarding long-term anterior/posterior capsular opacification (ACO/PCO) development and need for neodymium:Yttrium-Aluminum-Garnet (Nd:YAG) laser treatment due to visually disturbing PCO, and to study development of glistenings in the IOL materials.

METHODS

In a prospective, randomized, intra-individual, comparative trial, 50 cataract patients received either an AcrySof IQ^® SN60WF (Alcon, Fort Worth, TX, USA) or a Tecnis^® ZCB00 (Abbott Medical Optics, Santa Ana, CA, USA) IOL in the first operated eye, and the second eye received the IOL type not implanted in the first eye. Anterior/posterior capsular opacification (ACO/PCO) and fibrosis were monitored with slit-lamp photography and semi-automated digital analysis 2 and 3 years postoperatively. Glistenings were semi-quantitatively assessed in slit-lamp photographs. Nd:YAG laser treatment for visually disturbing PCO was monitored.

RESULTS

Visual outcomes were similar for the two IOLs. Anterior capsular fibrosis and/or opacification developed more often in SN60WF eyes. Mean PCO area percentage was larger in ZCB00 eyes 3 years after surgery, but severity score did not differ with statistical significance between the two IOLs. Six ZCB00 eyes and 2 SN60WF eyes underwent Nd:YAG laser treatment during a mean of 4 years 8 months after surgery. This difference was not statistically significant. A high amount of glistenings developed in most SN60WF IOLs, while only few ZCB00 IOLs displayed a low degree of glistenings.

CONCLUSION

Visual outcomes, PCO development over time and need for Nd:YAG laser treatment were similar for the two IOLs. Anterior capsule fibrosis/contraction and glistenings were more pronounced with the SN60WF IOL.

Posterior Capsule Opacification 9 Years after Phacoemulsification with a Hydrophobic and a Hydrophilic Intraocular Lens

Purpose

To compare the development of posterior capsule opacification (PCO) and survival rate without capsulotomy after implantation of a hydrophobic or hydrophilic acrylic intraocular lens (IOL) at the 9-year postoperative follow-up.

Methods

One of 3 experienced cataract surgeons performed standard phacoemulsification in one eye of 120 patients with cataract. The patients were randomized to implantation of either a hydrophobic acrylic IOL or a hydrophilic acrylic IOL. Both IOLs had sharp posterior edges. Retroillumination images of PCO were obtained with a fundus camera 9 years postoperatively and analyzed semiobjectively using POCOman computer software.

Results

Seventy-eight of the 120 patients completed the 9-year follow-up examination. Patients implanted with the hydrophilic IOL had significantly (p<0.001) more and denser PCO. The survival rate without Nd:YAG capsulotomy was significantly higher (p<0.001) in eyes with the hydrophobic IOL.

Conclusions

After 9 years, more and denser PCO developed in eyes with the hydrophilic IOL than the hydrophobic IOL. The survival rate without the need for capsulotomy was higher in eyes with the hydrophobic IOL.

Assessment of Optical Quality at Different Contrast Levels in Pseudophakic Eyes

Purpose. To assess visual function using Optical Quality Analysis System (OQAS) at varying levels of contrast in pseudophakic eyes. Methods. The study included patients admitted to Seoul St. Mary's Hospital between January and February 2012: 143 pseudophakic eyes with one of five intraocular lens types, examined 2–6 months after cataract surgery, and 93 normal eyes (enhanced visual acuity (VA) < 0.1 logMAR) in age-matched controls. Subjects were examined at three contrast levels using the OQAS. Results. At 100%, 20%, and 9% contrast, simulated mean VA was 0.16 ± 0.18 logMAR, 0.30 ± 0.18 logMAR, and 0.52 ± 0.17 logMAR, in normal eyes, and 0.16 ± 0.12 logMAR, 0.33 ± 0.20 logMAR, and 0.56 ± 0.21 logMAR, respectively, in pseudophakic eyes. Simulated VA decreased significantly when contrast was reduced, regardless of ocular status, age group, and lens type (p < 0.05). There were no significant differences between normal and pseudophakic eyes among subjects aged 50–69 (p > 0.05). Among subjects aged 70–79, pseudophakic eyes showed improved simulated VA (p = 0.000) and objective scattering index values (p = 0.008). Conclusions. Patients with intraocular lenses have similar or superior visual function when compared to those with normal eyes at 2–6 months after cataract surgery, even under low-contrast conditions.

Early clinical outcome with a new monofocal microincision intraocular lens

The purpose of this study was to evaluate the early visual and refractive outcomes of a new aspheric monofocal microincision intraocular lens (IOL). This retrospective case series included eyes of patients who underwent implantation of a microincision IOL following 1.8 mm manual coaxial microincision cataract surgery and who attended regular postoperative follow-up visits on the first week and first, third, and sixth months. The postoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refraction and predictability, intraoperative and postoperative complications, posterior capsule opacification (PCO), IOL centration, and surgically induced astigmatism (SIA) were evaluated. Sixty-three eyes of 38 patients ranging in age from 51 to 86 were included in the study. The mean preoperative BCVA was 0.52 ± 0.42 logMAR. At the postoperative sixth month, the mean postoperative UCVA and BCVA were 0.12 ± 0.11 and 0.01 ± 0.03 logMAR, respectively. The mean postoperative spherical equivalent refraction (SER) was -0.30 ± 0.49 D. The SER was within ± 1.00 D of the attempted correction in 95.2 % of the eyes. The mean SIA measured with vector analysis was 0.45 ± 0.28 D. Mild PCO was observed in 9 eyes (14.7 %) with none requiring Nd:Yag laser capsulotomy. On centration analysis, the IOL was found to be 0.26 mm on average to the supero-nasal position. The aspheric microincision IOL was safely implanted and provided satisfactory visual and refractive outcomes in the early postoperative period.

Glistenings 9 years after phacoemulsification in hydrophobic and hydrophilic acrylic intraocular lenses

PURPOSE

To compare the development of glistenings after implantation of a hydrophobic acrylic intraocular lens (IOL) (AcrySof SA60AT) and a hydrophilic IOL (BL27) and evaluate the effect on corrected distance visual acuity (CDVA) and contrast sensitivity 9 years postoperatively.

SETTING

St. Erik Eye Hospital, Stockholm, Sweden.

DESIGN

Prospective randomized clinical trial.

METHODS

One of 3 experienced cataract surgeons performed standard phacoemulsification in 1 eye of each patient. The patients were randomized to implantation of a hydrophobic acrylic IOL or a hydrophilic acrylic IOL. Both IOLs had sharp posterior edges. The CDVA and contrast sensitivity were measured 9 years postoperatively. Scheimpflug images of the IOLs were obtained to analyze glistenings, which were graded subjectively at the slitlamp and quantified objectively with digital image analysis using computer software.

RESULTS

Seventy-eight of the 120 patients were available for the 9-year follow-up examination. Patients with the hydrophilic IOL had statistically significantly fewer glistenings (P < .001). The development of glistenings was not correlated with IOL power, CDVA, or contrast sensitivity.

CONCLUSIONS

After 9 years, the hydrophobic IOL developed more glistenings than the hydrophilic IOL. Glistenings did not affect CDVA or contrast sensitivity.

FINANCIAL DISCLOSURE

Neither author has a financial or proprietary interest in any material or method mentioned.

Posterior capsular opacification and Nd:YAG capsulotomy rates with the iMics Y-60H and Micro AY intra-ocular lenses: 3-year results of a randomized clinical trial

PURPOSE

To compare the incidence and intensity of posterior capsular opacification (PCO) and neodymium:yttrium-aluminium-garnet (Nd:YAG) capsulotomy rates between two microincision intra-ocular lenses (IOLs) 3 years after surgery.

METHODS

Sixty-five patients randomly received a Y-60H IOL (HOYA Surgical Optics, Singapore) in one eye and a Micro AY IOL (PhysIOL, Liège, Belgium) in the contralateral eye during same-day bilateral cataract surgery. Eyes were examined 1 week, 20 months and 3 years after surgery. The amount of PCO (score: 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software (aqua). Additionally, the Nd:YAG capsulotomy rate was noted.

RESULTS

Three years postoperatively, the objective PCO score of Y-60H IOLs was 1.9 ± 1.7 compared to PCO score of 1.7 ± 2.2 for the Micro AY IOLs (p = 0.66). Thirty-four percentage of the Y-60H eyes had undergone Nd:YAG capsulotomy, compared to 49% of the Micro AY eyes (p = 0.04). Significantly, more capsular folds were observed in the Y-60H IOL group (p = 0.001). There was no significant difference in best-corrected visual acuity, rhexis/IOL overlap and anterior capsule opacification 3 years after surgery.

CONCLUSION

Both microincision IOLs showed high YAG rates and comparable PCO scores 3 years after surgery. In the light of this unsatisfying PCO performance, the advantage of the present microincision IOLs over conventional IOLs must be questioned.

Influence of a variable overall diameter hydrophilic acrylic sharp-edged single-piece intra-ocular lens on capsule opacification one year after surgery

BACKGROUND

To investigate the influence of the overall intraocular lens (IOL) diameter on posterior capsule opacification (PCO) formation.

METHODS

In this prospective randomized clinical trial, 124 eyes of 62 patients with bilateral age-related cataract were included. Each patient received a Corneal A501D IOL in one eye and a Corneal J501D IOL in the fellow eye. Best corrected visual acuity (BCVA) and digital slitlamp photographs were taken a 1 h, 1 week, 1, 3, 6 and 12 months postoperatively. The amount of PCO was assessed subjectively at the slitlamp and objectively using automated image-analysis software.

RESULTS

We found a mean BCVA of 0.81 ± 0.2 for the Corneal A501D group and 0.79 ± 0.21 for the Corneal J501D group. There was no significant difference 12 months after surgery between the two IOLs (p > 0.05). Objective PCO assessment resulted in a mean PCO score (scale 0-10) of 1.65 ± 1.71 was found for the Corneal J501D group and a score of 1.54 ± 1.64 was found for the Corneal A501D group (p > 0.05). The subjective PCO assessment at 1 year resulted in a mean PCO score of 2.0 ± 1.74 in the Corneal J501D group and 2.13 ± 1.64 in the Corneal A501D group (p > 0.05).

CONCLUSION

Both investigated IOLs showed good clinical performance regarding PCO and BCVA. Our study suggests that the use of an IOL with variable total diameter seems not to influence the rate of PCO formation.

Effect of hydrophobic acrylic versus hydrophilic acrylic intraocular lens on posterior capsule opacification: meta-analysis

PURPOSE

This meta-analysis aims to evaluate the differences in performance of posterior capsular opacification (PCO) between hydrophobic acrylic intraocular lens (IOLs) and hydrophilic acrylic IOLs.

SETTING

Tianjin Medical University, Tianjin Eye Hospital, Tianjin Key Laboratory of Ophthalmology and Visual Science, Tianjin, China.

DESIGN

Systematic review of randomized controlled trials (RCTs) or meta-analysis.

METHODS

An electronic literature search was performed using the PubMed, EMBASE and Cochrane Library database before May in 2013 to identify prospective RCTs comparing hydrophobic acrylic IOLs and hydrophilic acrylic IOLs in patients after phacoemulsification with IOL implantation with a follow-up time of at least 1 year. Pertinent studies were selected by meeting predefined criteria and reviewed systematically by meta-analysis. The PCO scores and YAG capsulotomy rate, as indicator of PCO, were measured and discussed in a meta-analysis. Standardized mean differences (SMD), relative risk ratio (RR), and the pooled estimates were computed according to a random effect model or fixed effect model.

RESULTS

Nine prospective RCTs involving 861 eyes were included in the current meta-analysis. The hydrophobic acrylic IOLs were favored and the pooled SMD of PCO severity was 1.72 (95% confidence interval (CI), 0.20 to 1.23, P = 0.0002) and 1.79 (95% CI, 0.95 to 2.64, P<0.0001) with 1-year follow-up and 2-year follow-up respectively. The pooled RR of Nd:YAG laser capsulotomy rates at postoperative 2-year follow-up was 6.96 (95% CI, 3.69 to 13.11, P<0.00001) comparing hydrophilic acrylic IOLs with hydrophobic acrylic IOLs.

CONCLUSIONS

Compared with hydrophilic acrylic IOLs, the hydrophobic acrylic IOLs showed superior reduction in rates of PCO and laser capsulotomy in 2-year follow-up. More RCTs with standard methods for longer follow-up are needed to validate the association.

Comparison of posterior capsule opacification with hydrophobic acrylic and hydrophilic acrylic intraocular lenses

PURPOSE

To compare posterior capsule opacification (PCO) 3 years postoperatively in contralateral eyes with a single-piece hydrophobic acrylic and 1 of 2 single-piece hydrophilic acrylic intraocular lenses (IOLs) with different configurations.

SETTING

Iladevi Cataract and IOL Research Institute, Ahmedabad, India.

DESIGN

Prospective randomized clinical trial.

METHODS

A hydrophobic Acrysof (hydrophobic group) or a hydrophilic C-flex (hydrophilic group C) or Akreos Adapt IOL (hydrophilic group A) was randomized for implantation in the fellow eye or vice versa of each patient. The Evaluation of Posterior Capsule Opacification (EPCO) area, EPCO score, and neodymium:YAG (Nd:YAG) capsulotomy rates were compared using digital photographs.

RESULTS

The study enrolled 68 patients. Although there was no significant difference at 1 month, the median EPCO score was statistically significantly lower in the hydrophobic group than in hydrophilic group C (P = .00) and hydrophilic group A (P = .000) at 3 years. There were no significant differences in the median EPCO area at 1 month; however, the area was statistically significantly less in the hydrophobic group than in hydrophilic group C and hydrophilic group A at 3 years (both P = .000). Four (12.9%) of 31 eyes in hydrophilic group C and 5 (16%) of 31 eyes in hydrophilic group A required an Nd:YAG capsulotomy; no eye in the hydrophobic group required a capsulotomy (P = .04 and P = .02, respectively).

CONCLUSION

Posterior capsule opacification was significantly less with the Acrysof hydrophobic acrylic IOL at 3 years.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Interventions for preventing posterior capsule opacification

BACKGROUND

Posterior capsule opacification (PCO) remains the most common long-term complication after cataract surgery. It can be treated by Nd:YAG laser capsulotomy, however this may lead to other complications and laser treatment is not available in large parts of the developing world. Therefore, many studies try to find factors influencing the development of PCO.

OBJECTIVES

To summarise the effects of different interventions to inhibit PCO. These include modifications of surgical technique and intraocular lens (IOL) design, implantation of additional devices and pharmacological interventions.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE, EMBASE, LILACS in March 2009 and reference lists of identified trial reports.

SELECTION CRITERIA

We included only prospective, randomised and controlled trials with a follow-up time of at least 12 months. Interventions included modifications in surgical technique explicitly to inhibit PCO, modifications in IOL design (material and geometry), implantation of additional devices and pharmacological therapy compared to each other, placebo or standard treatment.

DATA COLLECTION AND ANALYSIS

We extracted data and entered it into RevMan. We compared visual acuity data, PCO scores and YAG capsulotomy rates and performed a meta-analysis when possible.

MAIN RESULTS

Sixty six studies were included in the review. The review was divided into three parts. 1. Influence of IOL optic material on the development of PCO. There was no significant difference in PCO development between the different IOL materials (PMMA, hydrogel, hydrophobic acrylic, silicone) although hydrogel IOLs tend to have higher PCO scores and silicone IOLs lower PCO scores than the other materials. 2. Influence of IOL optic design on the development of PCO. There was a significantly lower PCO score (-8.65 (-10.72 to -6.59), scale 0 to 100) and YAG rate (0.19 (0.11 to 0.35)) in sharp edged than in round edged IOLs, however not between 1-piece and 3-piece IOLs. 3. Influence of surgical technique and drugs on the development of PCO. There was no significant difference between different types of intraoperative/postoperative anti-inflammatory treatment except for treatment with an immunotoxin (MDX-A) which led to a significantly lower PCO rate.

AUTHORS' CONCLUSIONS

Due to the highly significant difference between round and sharp edged IOL optics, IOLs with sharp (posterior) optic edges should be preferred. There is no clear difference between optic materials. The choice of postoperative anti-inflammatory treatment does not seem to influence PCO development.

Comparison of posterior capsule opacification development with 3 intraocular lens types: five-year prospective study

PURPOSE

To compare the effects of hydrophobic acrylic, silicone, and heparin-surface-modified poly(methyl methacrylate) (HSM PMMA) intraocular lenses (IOLs) on posterior capsule opacification (PCO).

METHODS

In this 5-year prospective study, the same surgeon performed standard phacoemulsification in patients who were randomized to implantation of a round-edged HSM PMMA IOL (809C), a round-edged silicone IOL (SI-40NB), or a sharp-edged hydrophobic acrylic IOL (AcrySof MA60BM). The neodymium:YAG capsulotomy rate was recorded. To evaluate PCO and the position of the anterior capsulorhexis, retroillumination digital photographs were taken 5 years postoperatively and analyzed using the POCOman computer-analysis system.

RESULTS

After 5 years, there was no significant difference in the fraction or severity of PCO between the silicone IOLs and acrylic IOLs (both P =1.0). The silicone IOL group had a significantly higher capsulotomy rate (29%) than the acrylic IOL group (8%) (P=.0068). The HSM PMMA IOL group had a significantly higher PCO fraction, severity, and capsulotomy rate (54%) than the silicone and acrylic groups. In all eyes, the fraction (P=.0076) and severity (P=.0081) of PCO were statistically significantly higher when the anterior capsulorhexis was partly decentered than when it was completely on the optic; within each IOL group, there was no significant difference.

CONCLUSION

After 5 years, there was no significant difference in the semiquantitative evaluation of PCO between the sharp-edged acrylic IOL and round-edged silicone IOL. Eyes with the HSM PMMA IOL had more PCO than eyes with the other IOLs.

Evaluating and defining the sharpness of intraocular lenses: microedge structure of commercially available square-edged hydrophilic intraocular lenses

PURPOSE

To evaluate the microstructure of the edges of currently available hydrophilic acrylic intraocular lenses (IOLs) in terms of their deviation from an "ideal" square as a follow-up of preliminary in vitro studies of experimental poly(methyl methacrylate) IOLs and commercially available foldable hydrophobic IOLs.

SETTING

Berlin Eye Research Institute, Berlin, Germany.

METHODS

Twenty-four designs of hydrophilic acrylic IOLs were used in this study. For each design, a +20.0 diopter (D) IOL and a +0.0 D IOL (or the lowest available plus dioptric power) were evaluated. The IOL edge was imaged under low-vacuum (0.7 torr), high-magnification scanning electron microscopy (SEM) using an environmental microscope and standardized technique. The photographs were imported to a digital computer program, and the area above the posterior-lateral edge, representing the deviation from a perfect square, was measured in square microns.

RESULTS

Currently available hydrophilic acrylic IOLs labeled as square edged had an area of deviation from a perfect square ranging from 60.84 to 871.51 microm(2) for the +20.0 D IOLs and from 35.52 to 826.55 microm(2) for the low-diopter IOLs. Although some differences in edge finishing between the IOLs analyzed were observed, edge surfaces of hydrophilic acrylic IOLs appeared overall smooth under environmental SEM.

CONCLUSIONS

Analysis of the microstructure of the optic edge of currently available square-edged hydrophilic acrylic IOLs showed a large variation of the deviation area from a perfect square.