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

The Synergistic Effects of Polyol Pathway-Induced Oxidative and Osmotic Stress in the Aetiology of Diabetic Cataracts

Cataracts are the world's leading cause of blindness, and diabetes is the second leading risk factor for cataracts after old age. Despite this, no preventative treatment exists for cataracts. The altered metabolism of excess glucose during hyperglycaemia is known to be the underlying cause of diabetic cataractogenesis, resulting in localised disruptions to fibre cell morphology and cell swelling in the outer cortex of the lens. In rat models of diabetic cataracts, this damage has been shown to result from osmotic stress and oxidative stress due to the accumulation of intracellular sorbitol, the depletion of NADPH which is used to regenerate glutathione, and the generation of fructose metabolites via the polyol pathway. However, differences in lens physiology and the metabolism of glucose in the lenses of different species have prevented the translation of successful treatments in animal models into effective treatments in humans. Here, we review the stresses that arise from hyperglycaemic glucose metabolism and link these to the regionally distinct metabolic and physiological adaptations in the lens that are vulnerable to these stressors, highlighting the evidence that chronic oxidative stress together with osmotic stress underlies the aetiology of human diabetic cortical cataracts. With this information, we also highlight fundamental gaps in the knowledge that could help to inform new avenues of research if effective anti-diabetic cataract therapies are to be developed in the future.

Comparison of the Incidence of Nd:YAG Laser Capsulotomy Based on the Type of Intraocular Lens

Background and Objectives: Posterior capsular opacification (PCO) is the most common long-term complication of successful cataract surgery and can cause visual impairment. We aimed to investigate the effects of intraocular lens (IOL) characteristics on PCO by comparing the incidence of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy for different types of intraocular lenses. Materials and Methods: A retrospective analysis was performed on 2866 eyes that underwent cataract surgery between January 2010 and December 2017, with at least 5 years of follow-up. The IOLs used for surgery were the hydrophobic lenses SN60WF (Alcon, Fort Worth, TX, USA), ZCB00 (Johnson & Johnson Vision, Santa Ana, CA, USA), and MX60 (Bausch & Lomb, Rochester, NY, USA), and the hydrophilic lens MI60 (Bausch & Lomb, Rochester, NY, USA). We analyzed the incidence of Nd:YAG laser capsulotomy according to the type of IOL used. Results: The incidence of Nd:YAG laser capsulotomy was significantly higher with MI60 lenses (31.70%, 175/552 eyes) compared to SN60WF (7.90%, 113/1431 eyes), ZCB00 (10.06%, 64/636 eyes), and MX60 (10.57%, 13/123 eyes; p < 0.001) lenses. The incidence of Nd:YAG laser capsulotomy was significantly lower with the hydrophobic IOLs (8.68%, 190/2190 eyes) than with the hydrophilic IOL (31.70%, 175/552 eyes; p < 0.001). Over time, the rate of increase in the cumulative number of Nd:YAG laser capsulotomy cases was the highest with MI60. The cumulative rate of Nd:YAG laser capsulotomy during the first 3 years was 4.90% with SN60WF (70/1431 eyes), 6.76% with ZCB00 (43/636 eyes), 8.94% with MX60 (11/123 eyes), and 26.10% with MI60 (144/552 eyes) lenses. Conclusions: The incidence of PCO is influenced by the material of the IOLs. The hydrophilic IOL was associated with a higher rate of Nd:YAG laser capsulotomy than the hydrophobic IOLs, with a shorter time to Nd:YAG laser capsulotomy.

Factors Associated with Reclosure of Posterior Capsule Aperture by Flat Opacifications with Pearls after Nd:YAG Laser Posterior Capsulotomy

In this retrospective case series, we investigated factors associated with posterior capsule aperture (PCA) reclosure following neodymium-yttrium aluminum garnet (Nd:YAG) laser posterior capsulotomy. The study encompassed patients who underwent cataract surgery with intraocular lens (IOL) implantation or a combined vitrectomy, cataract surgery, and IOL implantation between 2009 and 2022. PCA reclosure was observed in 22 eyes of 17 patients: 45% (10 eyes) underwent the triple procedure, and 55% (12 eyes) received cataract surgery with IOL implantation. In our clinic, 14% of patients were given IOLs with a 4% water content, while 73% (13 eyes) of those experiencing PCA reclosure had IOLs with a 4% water content. The mean interval between Nd:YAG capsulotomies was notably shorter than that between the initial cataract surgery and the first Nd:YAG laser capsulotomy. We also identified five stages of PCA reclosure progression. In conclusion, IOL water content may be linked to PCA reclosure, and the time to recurrence is shorter with each successive reclosure. Further research is needed to verify these findings and uncover additional contributing factors.

Posterior Capsule Opacification after Cataract Surgery via Implantation with Hydrophobic Acrylic Lens Compared with Silicone Intraocular Lens: A Systematic Review and Meta-Analysis

Hydrophobic acrylic intraocular lens (IOL) is the most popular material in cataract surgery. Posterior capsule opacification (PCO) is a long-term complication of cataract surgery. It can impair vision and adversely affect the prognosis of IOL delamination. The objective of this study was to perform a systematic review and meta-analysis to provide an updated evaluation of long-term complications and visual function after implantation with hydrophobic acrylic and silicone intraocular lenses. PubMed, Embase, and Cochrane Library were searched from January 2000 until March 2021. Randomized controlled trials (RCTs) and retrospective studies were finally included. The main outcomes were PCO value and neodymium-doped yttrium aluminum garnet (Nd : YAG) capsulotomy rate. Subgroup analysis was performed to compare hydrophobic acrylic and silicone IOLs during the follow-up period. Sensitivity analysis was also performed. The meta-analysis included a total of 17 studies. When the follow-up period was considered, the results of the analysis revealed higher PCO value (Group 3: standardized mean difference (SMD), −0.59; 95% confidence interval (CI), −0.90 to −0.28) and Nd : YAG capsulotomy rate (Group 3: risk ratio (RR), 0.60; 95% CI, 0.40–0.89) for hydrophobic acrylic IOLs than silicone IOLs during a long-term (≥6 years) follow-up. In conclusion, both the PCO value and the Nd : YAG capsulotomy rates were higher in hydrophobic acrylic IOLs group than the silicone IOLs group at long-term use (more than 6 years) after implantation.

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.

Long-Term Clinically Significant Posterior Capsular Opacification Development Pattern in Eyes Implanted with an Aspheric Monofocal Intraocular Lens with a Square Optic Edge

Purpose

To analyse the posterior capsular opacification (PCO) development pattern in the long term in eyes implanted with a monofocal intraocular lens (IOL) with a square edge all around the optic.

Methods

Longitudinal retrospective study is data analyzed from a total of 7059 eyes from 4764 patients (mean age: 75.8 years) undergoing cataract surgery with implantation of an aspheric monofocal IOL (Bi-Flex HL 677AB/677P, Medicontur, Budapest, Hungary). These data were retrospectively collected using the electronic medical record of the hospitals involved. Nd : YAG capsulotomy rates were calculated per year during a follow-up of more than 10 years. The Kaplan–Meier analysis was used to establish the transparent capsule survival rate.

Results

The Nd : YAG capsulotomy rate increased from 1.1% at 1 year postoperatively to 17.2% at 5 years after surgery. No significant differences were found between eyes with and without capsulotomy in terms of age (p = 0.202), gender (p = 0.061), type of anaesthesia used (p = 0.128), and presence of conditions such as hard cataract (p = 0.111) or pseudoexfoliation (p = 0.137). IOL power was significantly lower in those eyes of patients requiring Nd : YAG capsulotomy during the follow-up (p < 0.001). Significantly more eyes implanted with the preloaded model of the IOL required capsulotomy (p < 0.001). Mean survival time and rate were 9.38 years and 85.9%, respectively.

Conclusions

Most eyes undergoing cataract with implantation of the Bi-Flex IOL do not develop a clinically significant PCO requiring Nd : YAG capsulotomy in the long term. IOL material and design may be the main factors accounting for this finding.

Clinical Outcomes and Patient Satisfaction with a New Diffractive-Refractive Trifocal Intraocular Lens - A 12 Month Prospective Study

Purpose

To evaluate the clinical outcomes and patient satisfaction after implantation of Optiflex Trio, a new trifocal intraocular lens (IOL) following cataract surgery.

Methods

Patients undergoing phacoemulsification for age-related cataracts and who satisfy the eligibility criteria underwent bilateral implantation with Optiflex Trio trifocal IOL. At follow -up visits of 1, 3, 6, and 12 months, binocular uncorrected and corrected distance, intermediate and near visual acuity, reading performance, contrast sensitivity (CS) and patient satisfaction for dysphotopsia and spectacle independence were evaluated using questionnaires.

Results

A total of 54 eyes from 27 patients with mean age of 66.30±7.48 years were included in the study. At 12 months, 78% (n = 21) patients had binocular cumulative UDVA of 20/20 or better. Post-op SE refraction accuracy was within ±0.50 D for 93% (n = 50) eyes, and refractive cylinder accuracy was within ≤0.50 D in 94% (n = 51) eyes. The mean binocular UNVA was 0.01±0.05 LogMAR, and the mean UIVA at 60 and 80 cm was 0.07±0.06 and 0.03±0.05 LogMAR, respectively, at 12 months. Reading speeds at 40, 60 and 80 cm showed improvement overtime. No patient had complained of severe dysphotopsia, and none of the patients required glasses for any activity. No eye underwent YAG-laser capsulotomy for significant PCO at the end of mean follow-up.

Conclusion

After 12 months, Optiflex Trio trifocal IOL provided a complete visual restoration with good visual quality outcomes in terms of uncorrected distance, intermediate and near visual acuity. The incidence of dysphotopsia was low, and spectacle independence was high, resulting in good patient satisfaction.

Trial Registry

CTRI/2019/10/021647 (www.ctri.nic.in).

Intraocular Lens Refractive Index and Its Impact on External Surface Reflections

PURPOSE

To determine and compare the origin of the external surface reflections produced by commonly used intraocular lenses (IOLs).

METHODS

The specular reflection taking place at the anterior surface of eight types of IOLs (IOL power = 22.00 diopters [D]) with different refractive indices (RIs), optical design, and ultraviolet and blue light-filtering function were measured. The experimental set-up included a laser beam light source (3.5 mW, 532 nm) and a saline-filled model eye containing the IOL to be examined. External surface reflections were measured using a power meter, and the IOL surface reflectance (%) was compared among the eight IOLs investigated.

RESULTS

External reflections from the anterior surface of the studied implants increased as the RI of the IOL material increased. The IOL models composed of high RI material (RI = 1.56 ± 0.02) were found to have a more than threefold higher external surface reflections compared to those with low RI (RI = 1.45 ± 0.02). Ultraviolet or blue light-filtering functions showed no significant correlation with the external reflectance.

CONCLUSIONS

IOLs with a high RI are associated with external surface reflections that are more than threefold higher than those with lower RI. The "cat's eye" phenomenon seen in pseudophakic eyes by an outside observer strongly depends on the RI, but is independent of the filter incorporated in the IOL. [J Refract Surg. 2021;37(6):398-402.].

Evaluation of Nd:YAG Laser Capsulotomy Rates in a Real-Life Population

Objective

The objective of this study was to assess the rate of posterior capsule opacification (PCO), under “real-life” conditions, as measured by rates of Nd:YAG laser intervention, rather than from a controlled study from which patients with conditions predisposing to PCO have been excluded.

Methods and Analysis

This was a retrospective, multicenter study in an unselected consecutive cohort of patients undergoing surgery for senile cataract. Patients aged 18 years and older, previously implanted with the CT LUCIA 611P IOL, were contacted at 12, 18 and 24 months to ascertain if they had received Nd:YAG laser treatment. There was an additional assessment at 36 months at the Austrian centre.

Results

A total of 200 patients were recruited at two centers. Laser capsulotomy rates were 4.5% at 1 year and 10% by year 2 and 12% by year 3. Three Nd:YAG capsulotomies, carried out at other external centers, were performed for reasons other than PCO, including astigmatism, epiretinal membrane and ARMD. If these patients are excluded, the true rate of Nd:YAG carried out for PCO at 1 year was 3.5% and at 2 years was 8.5%.

Conclusion

It is critical to ensure that Nd:YAG capsulotomies are being performed only for the correct clinical reason. Carrying out unnecessary procedures places the patient at risk of adverse events, is a cost to the healthcare system, and is likely to have no direct visual benefit for the patient. In PCO studies, it should be a requirement to document the fibrosis grade to confirm that Nd:YAG capsulotomy was correctly indicated.

Physicochemical Analysis of Sediments Formed on the Surface of Hydrophilic Intraocular Lens after Descemet's Stripping Endothelial Keratoplasty

An intraocular lens (IOL) is a synthetic, artificial lens placed inside the eye that replaces a natural lens that is surgically removed, usually as part of cataract surgery. The opacification of the artificial lens can be related to the formation of the sediments on its surface and could seriously impair vision. The physicochemical analysis was performed on an explanted hydrophilic IOL and compared to the unused one, considered as a reference IOL. The studies were carried out using surface sensitive techniques, which can contribute to a better understanding of the sedimentation process on hydrophilic IOLs’ surfaces. The microscopic studies allowed us to determine the morphology of sediments observed on explanted IOL. The photoelectron spectroscopy measurements revealed the presence of organic and inorganic compounds at the lens surface. Mass spectroscopy measurements confirmed the chemical composition of deposits and allowed for chemical imaging of the IOL surface. Applied techniques allowed to obtain a new set of information approximating the origin of the sediments’ formation on the surface of the hydrophilic IOLs after Descemet’s stripping endothelial keratoplasty.

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.

Patients satisfaction and clinical outcomes of binocular implantation of a new trifocal intraocular lens

PURPOSE

To evaluate the clinical outcomes following bilateral implantation of PanOptix intraocular lens (IOL).

METHODS

This study included consecutive patients scheduled to undergo cataract or refractive lens exchange surgery between October 2017 and June 2018 at two centers. Manifest refraction, uncorrected distance visual acuity (UDVA), uncorrected intermediate visual acuity (UIVA, 60 cm) and uncorrected near visual acuity (UNVA, 40 cm), defocus curves, presence of dysphotopsia, need for spectacles, presence of posterior capsule opacification and visual function were evaluated at 6 months after surgery.

RESULTS

The IOL was implanted in 138 eyes of 69 patients. The mean binocular UDVA was 0.02 ± 0.05 logMAR, UIVA 0.06 ± 0.07 logMAR and UNVA 0.05 ± 0.07 logMAR. Defocus curve showed two peaks at 0.00 D and - 1.50 D. Complete spectacle independence was reported in 94.2% of the patients. The mean VF-14 test result was 97.7 ± 2.2 (93.2-100). Only one patient (1.4%) reported seeing bothersome halos. The presence of posterior capsule opacification was noted in seven eyes (10%), whereas Nd:Yag capsulotomy was required only in one eye.

CONCLUSIONS

This trifocal IOL provided excellent visual outcomes at all distances with high spectacle independence and patient's satisfaction.

Posterior Capsule Opacification after Cataract Surgery in Children Over Five Years of Age with Square-edge Hydrophobic versus Hydrophilic Acrylic Intraocular Lenses: A Prospective Randomized Study

OBJECTIVE

To compare the effects of hydrophobic and hydrophilic materials in square-edged acrylic intraocular lenses (IOLs) on the development of posterior capsule opacification (PCO) after pediatric cataract surgery.

METHODS

Patients were randomly assigned to group 1 (hydrophobic acrylic square-edged IOLs; 13 eyes) or group 2 (hydrophilic acrylic square-edged IOLs; 13 eyes). The study evaluated PCO rates using Evaluation of Posterior Capsule Opacification (EPCO) 2000 software at one, three, six and 12 months postoperatively. Postoperative measurements also included corrected distance visual acuity (CDVA), neodymium:yttrium-aluminum-garnet (Nd:YAG) capsulotomy and postoperative complications other than PCO.

RESULTS

Both groups had significant increases in PCO rates after one year. Comparison of the groups showed no significant differences in the EPCO scores at three (group 1, 0.007±0.016 vs group 2, 0.008±0.014; p=0.830), six (group 1, 0.062±0.103 vs group 2, 0.021±0.023; p=0.184), or twelve months postoperatively (group 1, 0.200±0.193 vs group 2, 0.192±0.138; p=0.902). We also found no significant group differences regarding the change (delta, Δ) in EPCO scores between three and six months (group 1, 0.055±0.09 vs group 2, 0.013±0.02; p=0.113) or between six and twelve months postoperatively (group 1, 0.139±0.14 vs group 2, 0.171±0.14; p=0.567). Twenty-three percent of patients required Nd:YAG capsulotomy at the twelve-month visit.

CONCLUSIONS

No differences in PCO rates were found between hydrophobic and hydrophilic acrylic square-edged IOLs in children between five and twelve years of age at one year of follow-up.

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.

Comparing the long-term impact on health care resources utilization and costs due to various single-piece acrylic monofocal intraocular lens implantation during cataract surgery: a cost-consequence analysis for the United Kingdom, Italy, and Denmark

PURPOSE

The objective of this study was to estimate the cost impact of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy and its complications due to single-piece acrylic monofocal intraocular lenses (IOLs) in the healthcare setting of United Kingdom, Italy, and Denmark.

MATERIALS AND METHODS

A hypothetical cost-consequence model was developed to estimate economic burden of Nd:YAG laser capsulotomy due to different single-piece acrylic monofocal IOLs. Cumulative incidence of Nd:YAG laser capsulotomy at 3 years after cataract surgery with five single-piece monofocal acrylic IOLs was sourced from retrospective data analysis of electronic medical records of cataract patients in the United Kingdom. Risk probability of post-Nd:YAG laser complications, ie, retinal detachment, glaucoma, and cystoid macular edema at 3 years was derived using published literature. Unit costs were taken from publicly available sources with all costs converted to euro (€). Number of cataract procedures per year for each country was sourced from Eurostat statistics.

RESULTS

For the estimated cataract procedures carried out nationally every year, single-piece monofocal hydrophobic AcrySof IOL was associated with substantially lower cases of Nd:YAG laser capsulotomy procedures and subsequent complications in 3 years after cataract surgery when compared to other single-piece monofocal acrylic IOLs. The total cost savings with the use of AcrySof over other IOLs in countries assessed ranged from €0.5 to €4.7 million (vs AMO Tecnis) and €2.1 to €17.9 million (vs Rayner C-/Super-flex).

CONCLUSION

Incidence of Nd:YAG capsulotomy due to the choice of IOL could significantly affect healthcare budgets in the post-cataract surgery period. Our analysis indicates that single-piece monofocal AcrySof IOLs is the most cost-saving treatment option for health care systems when compared to other acrylic single-piece IOLs.

Advances and challenges of intraocular lens design [Invited]

Phacoemulsification technique with intraocular lens implantation has been a common treatment for cataract patients. With rising demand among the public, new technologies for lens design have emerged to minimize intraocular aberrations, improving visual quality to the largest extent. This paper systematically reviews the development of materials applied in lens manufacturing, the different categories of intraocular lenses, and respective design principles. The advantages and potential drawbacks of intraocular lenses are illustrated in the paper, and prospective research to improve the design are presented in the end.

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.

Three-year incidence of Nd:YAG capsulotomy and posterior capsule opacification and its relationship to monofocal acrylic IOL biomaterial: a UK Real World Evidence study

Purpose

To evaluate 3-year incidence of Nd:YAG capsulotomy and PCO and compare the effect of different IOL materials.

Methods

Data were retrospectively collected from seven UK ophthalmology clinics using Medisoft electronic medical records. Eyes from patients ≥65 years undergoing cataract surgery with implantation of acrylic monofocal IOLs during 2010–2013 and 3-year follow-up were analysed. Nd:YAG capsulotomy and PCO incidence proportions were reported for 3 IOL cohorts: AcrySof, other hydrophobic and hydrophilic acrylic IOLs. Unadjusted/adjusted odds ratios (OR) of Nd:YAG capsulotomy were calculated through logistic regression for non-AcrySof cohorts versus AcrySof. A sub-group analysis in single-piece IOLs (>90% of sample eyes) was also performed.

Results

The AcrySof cohort included 13,329 eyes, non-AcrySof hydrophobic 19,025 and non-AcrySof hydrophilic 19,808. The 3-year Nd:YAG capsulotomy incidence (95% CI) for AcrySof (2.4%, 2.2–2.7%) was approximately two times lower than non-AcrySof hydrophobic IOLs (4.4%, 4.1–4.7%) and approximately fourfold lower than non-AcrySof hydrophilic IOLs (10.9%, 10.5–11.3%). Trends were similar in PCO incidence (AcrySof: 4.7%; non-AcrySof hydrophobic: 6.3%; non-AcrySof hydrophilic: 14.8%). Also in the analysis restricted to single-piece IOLs, the pattern remained (2.4% vs 5.1% vs. 10.9%, respectively). Adjusted regression analysis showed a approximately two and fivefold increased odds of Nd:YAG for non-AcrySof hydrophobic and hydrophilic acrylic IOLs respectively vs. AcrySof IOLs. Nd:YAG capsulotomy ORs were similar and remained statistically significant in the single-piece IOL sub-group.

Conclusions

Real-world evidence shows that within 3 years following implantation, AcrySof IOLs are significantly superior in reducing Nd:YAG capsulotomy and PCO incidence compared to other hydrophilic and hydrophobic acrylic IOLs.

Comparing capsular bag performance of a hydrophilic and a hydrophobic intraocular lens: A randomised two-centre study

Purpose:

To evaluate the capsular bag performance and posterior capsule opacification development of two intraocular lenses differing in material and design.

Methods:

This study included patients who were scheduled for cataract surgery and compared a hydrophilic intraocular lens (Super flex® intraocular lens; Rayner Surgical, Worthing, UK) with a hydrophobic intraocular lens (AcrySof® SA60AT; Alcon, Fort Worth, TX, USA). Follow-ups were performed 1 month and 2 years after cataract surgery, including a slit lamp examination and retroillumination images.

Results:

In total, 80 eyes of 80 patients were recruited. At the 1-month follow-up, 6 of 39 cases had a gap between the posterior lens capsule and intraocular lens (1 case in the hydrophilic intraocular lens group and 5 cases in the hydrophobic intraocular lens group; p = 0.348). Objective and subjective posterior capsule opacification scoring showed no statistically significant difference between both groups (p = 0.123).

Conclusion:

Both intraocular lens showed a good capsular bag performance and a relatively low posterior capsule opacification development within the first 2 years after surgery.

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.

Influence of material and haptic design on the mechanical stability of intraocular lenses by means of finite-element modeling

Intraocular lenses (IOLs) are used in the cataract treatment for surgical replacement of the opacified crystalline lens. Before being implanted they have to pass the strict quality control to guarantee a good biomechanical stability inside the capsular bag, avoiding the rotation, and to provide a good optical quality. The goal of this study was to investigate the influence of the material and haptic design on the behavior of the IOLs under dynamic compression condition. For this purpose, the strain-stress characteristics of the hydrophobic and hydrophilic materials were estimated experimentally. Next, these data were used as the input for a finite-element model (FEM) to analyze the stability of different IOL haptic designs, according to the procedure described by the ISO standards. Finally, the simulations of the effect of IOL tilt and decentration on the optical performance were performed in an eye model using a ray-tracing software. The results suggest the major importance of the haptic design rather than the material on the postoperative behavior of an IOL. FEM appears to be a powerful tool for numerical studies of the biomechanical properties of IOLs and it allows one to help in the design phase to the manufacturers.

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.

German claims data analysis to assess impact of different intraocular lenses on posterior capsule opacification and related healthcare costs

Aim

Cataract extraction is one of the most frequent surgeries in Germany. In most cases, the clouded natural lens is replaced by a hydrophobic or hydrophilic acrylic intraocular lens (IOL) implant. The most common long-term complication after cataract surgery is the development of a posterior capsule opacification (PCO). Although no precise real world data are available, published evidence suggests a lower risk for PCO development for hydrophobic acrylic IOLs compared to hydrophilic acrylic IOLs. Therefore, in the present study we assessed real world data on the impact of different IOL material types on the incidence of post-operative PCO treatment.

Subject and methods

In this retrospective study, we included 3,025 patients who underwent cataract extraction and implantation of either an acrylic hydrophobic or hydrophilic IOL in 2010. We assessed clinical outcomes and direct costs in a 4-year follow-up period after cataract surgery from a statutory health insurance (SHI) perspective in Germany.

Results

PCO that required capsulotomies occurred significantly (p < 0.0001) less frequent in patients who had received a hydrophobic IOL (31.57% of 2,078 patients) compared to the group with hydrophilic IOL implants (56.6% of 947 patients) and costs per patient for postoperative treatment in a 4-year follow-up were 50.03 € vs. 87.81 € (i.e. 75% higher in the latter group, p < 0.0001).

Conclusion

Considering the high prevalence of cataract, the economic burden associated with adverse effects of cataract extraction is of great relevance for the German SHI. Hydrophobic lenses seem to be superior regarding both medical and economic results.

Long-term efficiency of cataract surgery with hydrophilic acrylic Ioflex intraocular lens

OBJECTIVE

To evaluate the efficiency of long-term cataract surgery using low-cost intraocular lens implantation in community campaigns.

METHODS

Fifty-eight randomly selected patients were evaluated four years after phacoemulsification and Ioflex intraocular lens implantation. Causes of low visual acuity related to the intraocular lens were evaluated, and treatment costs were calculated.

RESULTS

The mean age of patients was 72±10.2 years. Four years after surgery, 25 eyes (43.0%) had decreased visual acuity related to the intraocular lens: posterior capsule opacification was noted in 24 eyes (41.3%), and intraocular lens opacification was noted in one eye (1.7%). The total cost of the post-surgical complication treatments represented 6.3% of the initial budget of the entire surgical patient group.

CONCLUSIONS

The efficiency of cataract surgery with low-cost Ioflex intraocular lens implantation was significantly reduced in a long-term follow-up study because postoperative complications related to intraocular lenses emerged at higher rates than when the gold-standard treatment was used.

Biocompatibility of Intraocular Lenses

The performance of an intraocular lens is determined by several factors such as the surgical technique, surgical complications, intraocular lens biomaterial and design, and host reaction to the lens. The factor indicating the biocompatibility of an intraocular lens is the behavior of inflammatory and lens epithelial cells. Hence, the biocompatibility of intraocular lens materials is assessed in terms of uveal biocompatibility, based on the inflammatory foreign-body reaction of the eye against the implant, and in terms of capsular biocompatibility, determined by the relationship of the intraocular lens with residual lens epithelial cells within the capsular bag. Insufficient biocompatibility of intraocular lens materials may result in different clinical entities such as anterior capsule opacification, posterior capsule opacification, and lens epithelial cell ongrowth. Intraocular lenses are increasingly implanted much earlier in life in cases such as refractive lens exchange or pediatric intraocular lens implantation after congenital cataract surgery, and these lenses are expected to exhibit maximum performance for many decades. The materials used in intraocular lens manufacture should, therefore, ensure long-term uveal and capsular biocompatibility. In this article, we review the currently available materials used in the manufacture of intraocular lenses, especially with regard to their uveal and capsular biocompatibility, and discuss efforts to improve the biocompatibility of intraocular lenses.

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.

Postoperative posterior capsular striae and the posterior capsular opacification in patients implanted with two types of intraocular lens material

AIM

To evaluate the incidence of postoperative posterior capsular striae (PCS) and its influence on posterior capsular opacification (PCO) in patients implanted with two types of lens material.

SETTING

Tertiary eye care center in central rural India.

STUDY DESIGN

A prospective, observational, nonrandomized study.

MATERIALS AND METHODS

The study included 1247 patients having age-related cataract scheduled for removal by phacoemulsification technique and implantation of hydrophilic or hydrophobic intraocular lens (IOL). Demographic profile, nuclear grading, axial length, and IOL power were noted. Details of PCS were noted on the 1st postoperative day in patients with clear cornea. Postoperative follow-up was ensured to study the status of PCS and development of PCO.

RESULTS

The overall incidence of PCS was 19.8% (247 out of 1247 eyes). Out of 1247 patients, 641 patients (51.4%) had hydrophilic IOL implantation and 201 eyes had PCS (31.4%) and 606 patients (48.6%) had hydrophobic IOL implantation and 46 eyes had PCS (7.6%), P = 0.04. Three and more striae were seen in 119 eyes (119/641, 18.6%) in hydrophilic group and 4 eyes (4/606, 0.66%) in hydrophobic group. Sixty-two eyes (62/201, 30.9%) in hydrophilic group with multiple PCS were reported with persistent striae after 6 months of surgery. Two eyes in hydrophobic group had persistent striae even after 3 years of follow-up. Evaluation of PCO score of the hydrophilic group was 0.6 whereas of the hydrophobic group was 0.1 (P = 0.04). Ten patients of the hydrophilic group only required neodymium-doped yttrium aluminum garnet (ND: YAG) laser capsulotomy.

CONCLUSION

The incidence of PCS was higher in hydrophilic than hydrophobic IOLs. Multiple PCS persisting in patients beyond 6 months after operation should be followed up for early development of PCO, particularly in patients implanted with hydrophilic IOL.

Laser capsulotomy following cataract surgery: Comparing time to capsulotomy with implantation of two broadly used intraocular lenses

PURPOSE

The aim of this study is to compare the length of time from uneventful cataract surgery using one of two common posterior chamber intraocular lenses (IOLs) (hydrophilic versus hydrophobic acrylic) to laser capsulotomy.

MATERIALS AND METHODS

Retrospective analysis of all patients who underwent neodymium: yttrium-aluminum-garnet laser capsulotomy between 2011 and 2014 following uneventful phacoemulsification surgery at a tertiary university-affiliated medical center. Medical records were reviewed for demographics, ocular comorbidities, operative details, postoperative follow-up, and findings of the precapsulotomy ophthalmologic examination. Parameters, including age, sex, laterality, visual acuity, surgeon's experience, and time from cataract surgery to capsulotomy, were compared between patients who received hydrophilic (SeeLens AF, Kibbutz Hanita, Israel) or hydrophobic (AcrySof SA60AT, Alcon Laboratories, Fort Worth, TX, USA) IOLs.

RESULTS

The cohort included 222 patients (255 eyes), of which, 107 were male and 115 female, of mean age 73 ± 8 years. Mean interval from cataract surgery to laser capsulotomy was 24 months (range 2-70) and was significantly shorter in patients with SeeLens (23 ± 13 months) than AcrySof IOL implantation (28 ± 13 months, P = 0.04). Lens type remained significant in multivariate analysis after including surgeon's experience and age as potential confounders (P = 0.04).

CONCLUSION

The hydrophilic SeeLens IOL is associated with a significantly shorter time interval from cataract surgery to laser capsulotomy than the hydrophobic AcrySof IOL.

Physicochemical and surface properties of acrylic intraocular lenses and their clinical significance

To analyze and compare several commercially available acrylic intraocular lenses (IOLs) with particular regard to their clinical significance, we examined the physicochemical and surface properties of four currently available acrylic IOLs using static water contact angle, atomic force microscopy (AFM), Raman spectroscopy, and differential scanning calorimetry (DSC) measurements. The hydrophobic acrylic IOLs, ZA9003, and MA60BM, had contact angles ranging from 77.9° ± 0.65° to 84.4° ± 0.09°. The contact angles in the hydrophilic acrylic (970C) and heparin-surface-modified (HSM) hydrophilic acrylic IOLs (BioVue) were 61.8° ± 0.45° and 69.7° ± 0.76°, respectively. The roughness of the IOL optic surface differed depending on the type of IOL (p < 0.001). The surface roughness of BioVue had the lowest value: 5.87 ± 1.26 nm. This suggests that the BioVue IOL may lead to reduced cellular adhesion compared to the unmodified IOLs. All IOLs including those composed of acrylic optic materials from different manufacturers showed distinct Raman spectra peaks. The glass transition temperatures (T_g) for the hydrophobic acrylic IOLs were between 12.5 and 13.8 °C. These results suggest that the intraoperative and postoperative behavior of an IOL can be predicted. This information is also expected to contribute greatly to the industrial production of reliable biocompatible IOLs.

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.

Epidemiological evaluation of YAG capsulotomy incidence for posterior capsule opacification in various intraocular lenses in Japanese eyes

Background and objective

We investigated the yttrium aluminum garnet (YAG) capsulotomy rates in various intraocular lenses (IOLs).

Study design/patients and methods

We retrospectively analyzed 23,440 eyes implanted with either MA60BM, MA60AC, VA-60BB, CeeOnEdge, Clariflex, Technis Z9002, SI-40NB, or UV26T IOLs. We calculated the YAG capsulotomy rates at 1, 3, 5, and 10 years post lens implantation.

Results

YAG capsulotomy rates at 3 years postimplantation for the eight groups of IOLs were, respectively, 3.7%, 3.9%, 23.7%, 3.4%, 4.5%, 4.7%, 10.4%, and 21.0%. YAG capsulotomy rates at 10 years postimplantation for the MA60BM and SI-40NB IOLs were, respectively, 9.1% and 15% (P<0.05). The average YAG rates for all sharp-edged and round-edged IOLs at 5 years postimplantation were, respectively, 5.2%±0.7% and 25.6%±9.0% (P<0.05).

Conclusion

In all studied IOLs, posterior capsule opacification prevention seemed to be associated with the posterior optic sharp-edge design. Round-edged silicone IOLs may also retard posterior capsule opacification formation, though not as much as sharp-edged IOLs. As the follow-up period progressed, round-edged silicone IOLs showed significantly higher YAG rates than sharp-edged IOLs.

Prospective Randomized Intraindividual Comparison of Posterior Capsule Opacification After Implantation of an IOL With and Without Heparin Surface Modification

PURPOSE

To compare posterior capsule opacification (PCO) of a hydrophobic acrylic heparin surface modified intraocular lens (HSM-IOL) and an uncoated IOL (UC-IOL) 1 year after implantation.

METHODS

One hundred two eyes of 51 patients underwent routine phacoemulsification with randomized implantation of a HSM-IOL in one eye (the HSM-IOL group) and a UC-IOL in the fellow eye (the UC-IOL group). Morphologic PCO evaluation was performed comparing digital photographs in retroillumination using the Evaluation of Posterior Capsule Opacification (EPCO) system, grading the density of the opacification from 0 to 4 (0 = none, 1 = minimal, 2 = mild, 3 = moderate, and 4 = severe). Distance visual acuities, subjective manifest refraction, pupil size, straylight measurements, flare in the anterior chamber using a laser flare meter, and contrast sensitivity were also evaluated.

RESULTS

The mean total EPCO score was slightly higher in the HSM-IOL group (0.50 ± 0.45) compared to the UC-IOL group (0.45 ± 0.46), but did not reach statistical significance. No statistically significant differences were found in the other main outcome parameters (straylight measurement, distance visual acuities, flare in the anterior chamber, and mesopic and photopic contrast sensitivity) when comparing both IOLs.

CONCLUSION

Although the HSM-IOL showed decreased flare 1 day postoperatively, no statistically significant differences regarding PCO were found 1 year postoperatively.

Comparison of posterior capsule opacification at 360-degree square edge hydrophilic and sharp edge hydrophobic acrylic intraocular lens in diabetic patients

AIM

To compare posterior capsule opacification (PCO) degree and visual functions after phacoemulsification in eyes implanted with 360-degree square edge hydrophilic acrylic intraocular lens (IOL) (570C C-flex, Rayner) and sharp edge hydrophobic acrylic IOL (Sensar AR40e, AMO) in diabetic patients.

METHODS

Sixty diabetic patients underwent uneventful phacoemulsification and randomly implanted one of the two IOLs. The PCO value was measured by retroillumination photographs and Evaluation of Posterior Capsule Opacification (EPCO) 2000 image-analysis software at 1, 6, 12, and 24mo after surgery. Visual acuity, and contrast sensitivity in photopic and mesopic conditions were also examined at each follow up time point. The incidence of eye that required Nd:YAG laser posterior capsulotomy were also compared.

RESULTS

There was not any statistically significant difference in PCO scores between Rayner C-flex 570C group and Sensar AR40e group at each follow up time point. Visual acuity, Nd:YAG capsulotomy incidence and contrast sensitivity also had no significant difference during the 24mo follow-up.

CONCLUSION

For diabetic patients, Rayner 570C C-flex and Sensar AR40e IOLs are same effective for prevent PCO. The 360-degree square edge design maybe is a good alternative technique to improve PCO prevention.

Hinged Capsulotomy--Does it Decrease Floaters After Yttrium Aluminum Garnet Laser Capsulotomy?

Objectives:

The objective was to compare conventional circular yttrium aluminum garnet (YAG) laser capsulotomy with hinged capsulotomy to manage posterior capsular opacification (PCO).

Materials and Methods:

This prospective, randomized clinical trial enrolled pseudophakic patients with visually significant posterior capsule opacification. Patients were randomized to undergo posterior YAG laser capsulotomy with either conventional circular technique or a new technique with an inferior hinge. At 1-month postoperatively, patients were asked if they had any annoying floaters and the responses were compared between groups. P < 0.05 was considered statistically significant.

Results:

A total of 83 patients were enrolled. Forty-three patients underwent hinged posterior YAG capsulotomy and 40 patients underwent routine circular capsulotomy. At 1-month postoperatively, there was a statistically significant decrease in annoying floaters in the group that underwent circular capsulotomy (P = 0.02). There was no statistically significant association in the total energy delivered (P = 0.4) or the number of spots (P = 0.2) and patient perception of annoying floaters.

Conclusion:

Hinged YAG capsulotomy was effective at decreasing the rate of floaters in patients with PCO.

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.

Effect of four different intraocular lenses on posterior capsule opacification

AIM

To evaluate the impact of 4 different intraocular lenses (IOLs) on posterior capsule opacification (PCO) by comparing the neodymium: yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy rates.

METHODS

This retrospective study included 4970 eyes of 4013 cataract patients who underwent phacoemulsification and IOL implantation between January 2000 and January 2008 by the same surgeon at one clinic. Four different IOLs were assessed. The outcome parameter was the incidence of Nd:YAG laser posterior capsulotomies.

RESULTS

An Nd:YAG laser posterior capsulotomy was performed in 153 (3.07%) of the 4970 eyes. The mean follow-up time was 84mo for all of the IOL groups. The percentage of eyes developing PCO was significantly greater for the acrylic hydrophilic IOLs than for the hydrophobic IOLs, although eyes with acrylic hydrophilic IOLs did not require Nd:YAG laser capsulotomy as soon as eyes with acrylic hydrophobic IOLs. There was no difference between the long-term PCO rates when 1- and 3-piece acrylic hydrophobic IOLs were compared or when IOLs made of the same material but with different haptic angles were compared.

CONCLUSION

In this study, eyes with acrylic hydrophilic IOLs were more likely to develop PCO than those with acrylic hydrophobic IOLs. The lens design (1-piece versus 3-piece and varying haptic angles) did not affect the PCO rate.

Square-edge intraocular lenses and epithelial lens cell proliferation: implications on posterior capsule opacification in an in vitro model

Background

To evaluate lens epithelial cell (LEC) proliferation with two different designs (one-piece or three-piece) of hydrophobic acrylic IOLs with 360° square optic edge using an in vitro culture model of posterior capsule opacification (PCO).

Methods

This experimental study was conducted at the Department of NEUROFARBA, Section of Pharmacology, University of Florence, Italy. Human LECs were seeded and cultured in transwell cell culture inserts coated with a type-IV collagen membrane on which an IOL (one-piece Tecnis-1 or three-piece AR40E, Abbott Medical Optics Inc.) had been previously placed. As control, cells were plated on the insert membrane without an IOL. At day six (cells confluent in controls) IOLs were removed and cell counting, viability and cell density under and outside the IOLs were evaluated.

Results

No statistically significant difference in the number of cells (p > 0.05) between inserts with the one-piece and three-piece IOLs was found. Cell density in the area under each IOL was significantly lower than in the area outside of it (p < 0.05), or in the control insert. (p < 0.05). Cell density under the single-piece IOL was not significantly different from that under the three-piece IOL (p > 0.05).

Conclusions

A 360° sharp-edge played a crucial role in avoiding LEC migration under the IOL and preventing the formation of PCO after cataract surgery. Long term clinical evaluation is necessary to estimate functional results.

Economic considerations related to choice of intraocular lens (IOL) and posterior capsule opacification frequency - a comparison of three different IOLs

PURPOSE

To evaluate the posterior capsule opacification (PCO) rates in three different modern standard intraocular lenses (IOL) and analyse the related cost.

METHODS

Retrospective study of medical records from 1527 patients who underwent uneventful cataract surgery by phacoemulsification with posterior chamber implantation of either AcrySof SN60 (n = 375), Akreos Adapt (n = 350) or Tecnis Acryl IOL (n = 801). All surgeries were performed by the same surgeon using the same surgical technique and equipment. Primary end-point was neodymium:yttrium-aluminium-garnet (Nd:YAG) capsulotomy for visual impairment secondary to PCO. Cost of IOL material and Nd:YAG capsulotomy for PCO was then evaluated and compared between the IOLs.

RESULTS

Mean follow-up was 41.5 months, and the only statistically significant variable of developing PCO was IOL type and individual follow-up time. Nd:YAG capsulotomy was performed in 7.47% in the AcrySof group, 17.71% in the Akreos group and 3.75% in the Tecnis group. Average cost for Nd:YAG capsulotomy per surgery was €18.75 in the AcrySof SN60 group, €44.25 in the Akreos Adapt group and €9.25 in the Tecnis Acryl group. The combined cost of cataract surgery and PCO treatment was €9.81 higher in for the Akreos Adapt group than the other two combined.

CONCLUSIONS

This retrospective study shows that the risk of PCO and Nd:YAG capsulotomy is significantly higher in hydrophilic Akreos IOL compared with both AcrySof and Tecnis hydrophobic IOLs. The increased risk of PCO in the hydrophilic IOL is related to higher total average costs for cataract surgery.

Three-year incidence and factors associated with posterior capsule opacification after cataract surgery: The Australian Prospective Cataract Surgery and Age-related Macular Degeneration Study

PURPOSE

To assess 3-year incidence and associated factors of posterior capsule opacification (PCO) after phacoemulsification surgery.

DESIGN

Cohort study.

METHODS

A total of 1934 consecutive patients aged ≥64 years undergoing phacoemulsification surgery at Westmead Hospital were recruited, of whom 1495 (77.3%) had retroillumination anterior segment images taken of the surgical eyes after 1 month and at a further postoperative visit within 3 years. Severe PCO was defined if the view of the optic disc was obscured, or neodymium-yttrium-aluminum-garnet capsulotomy was performed. Cumulative incidence of PCO was estimated using Kaplan-Meier methods. Associations of PCO with surgeon groups and different types of implanted intraocular lenses (IOLs) were assessed, adjusting for age, sex, diabetes, and ethnicity.

RESULTS

Three-year cumulative incidence of PCO was 38.5% (95% confidence interval [CI] 36.1%-40.9%) among the 1495 patients, including 4.7% (95% CI 3.5%-5.8%) with severe PCO. PCO incidence was higher in: (1) eyes operated on by junior trainees (49%) compared to those by senior ophthalmologist surgeons (36%) (adjusted odds ratio [OR] 1.6, 95% CI 1.2-2.0); and (2) eyes with hydrophobic, 3-piece (either square-edged [51%, OR 2.3, 95% CI 1.4-3.6] or partial-round-edged [39%, OR 1.5, 95% CI 1.1-2.1]), or hydrophilic IOLs (64%, OR 2.9, 95% CI 1.9-4.4) compared to those with single-piece, square-edged, hydrophobic IOLs (34%), after additional adjustment for surgeon group.

CONCLUSIONS

Predominantly mild PCO occurred in one-third of eyes after phacoemulsification surgery. Possible predisposing factors associated with PCO development include surgery performed by ophthalmologic trainees and the use of hydrophilic or other hydrophobic IOLs apart from the single-piece, square-edged one.