Incidence of Nd:YAG laser capsulotomies after cataract surgery: comparison of 3 square-edged lenses of different composition

Five-Year Incidence of Nd:YAG Capsulotomy After Cataract Surgery with Different Single-Piece Monofocal Intraocular Lenses: A Follow-Up Study of 3955 Eyes

Purpose

To estimate the incidence of neodymium-doped yttrium aluminum garnet laser (Nd:YAG) capsulotomy up to five years after cataract surgery with different single-piece acrylic monofocal IOLs in a Spanish cohort.

Patients and Methods

Data were extracted from electronic medical records. Eligible participants were aged ≥65, had cataract surgery with one of five different acrylic monofocal IOLs (Alcon AcrySof, AJL LLASY60, Medicontur Bi-flex, IOL Tech Stabibag and Zeiss Asphina), and more than six months baseline data. Participants were followed up to five years from surgery and up to six months from Nd:YAG. The incidence of Nd:YAG was compared between the IOLs and multivariate analyses were conducted to identify predictors of Nd:YAG incidence at five-years after cataract surgery.

Results

The initial cohort included 9545 patients with 14,519 eyes (53% female, average age 75 years). Of those, 3955 eyes were available for analysis five years after cataract surgery. Throughout the five years post-surgery, Nd:YAG incidence was consistently lower with Alcon Acrysof IOLs than the other IOLs. At five years the Nd:YAG incidence rate for Alcon Acrysof was 8.8%. In comparison, the incidence was 47.4% for AJL LLASY60 (OR = 9.54, 95% CI [6.57, 13.84]), 44.3% for Zeiss Asphina (OR = 8.35, 95% CI [5.85, 11.94]) and 44.0% for IOL Tech Stabibag (OR = 8.02, 95% CI [4.60, 13.84]).

Conclusion

Alcon AcrySof IOLs have a consistently lower risk of Nd:YAG incidence over a long follow-up period after cataract surgery, highlighting the importance of IOL choice for patients' long-term outcomes.

Long-term incidence of posterior capsular opacification in patients with non-infectious uveitis

Little is known about the long-term incidence of posterior capsule opacification (PCO) after cataract surgery in patients with uveitis. This retrospective study included 211 eyes of 146 patients with non-infectious uveitis who underwent cataract surgery and implantation of an Acrysof SN60WF (Surface: plasma-treated, Optic and Haptic: hydrophobic acrylic), iSert XY-1 (Surface: UV-ozone-treated, Optic and Haptic: hydrophobic acrylic), or iSert 251/255 (Surface: UV-ozone-treated, Optics: hydrophobic acrylic, Haptic: polymethyl methacrylate). The cumulative incidences of PCO and subsequent yttrium–aluminum-garnet (Nd:YAG) capsulotomy over the 5-year follow-up were analyzed, and patients who were implanted with different intraocular lenses (IOLs) were compared. Mixed-effects Cox proportional hazard models showed that, compared with the Acrysof group, the iSert XY-1 group had higher risks of PCO (adjusted HR, 7.26; 95% CI, 1.82–28.8) and Nd:YAG capsulotomy (adjusted HR, 6.50; 95% CI, 1.55–27.2). Similar results were obtained when the Acrysof group was compared with the iSert 251/255 group for PCO (adjusted HR, 8.22; 95% CI, 2.35–28.7) and Nd:YAG capsulotomy (adjusted HR, 8.26; 1.90–36.0). These data suggest that a plasma-treated surface, hydrophobic acrylic optic and hydrophobic acrylic haptic, of the IOL could enhance biocompatibility even under inflammatory conditions, thus suppressing PCO development.

Factors Affecting Posterior Capsule Opacification in the Development of Intraocular Lens Materials

Posterior capsule opacification (PCO) is the most common complication arising from the corrective surgery used to treat cataract patients. PCO arises when lens epithelial cells (LEC) residing in the capsular bag post-surgery undergo hyper-proliferation and transdifferentiation into myofibroblasts, migrating from the posterior capsule over the visual axis of the newly implanted intraocular lens (IOL). The developmental pathways underlying PCO are yet to be fully understood and the current literature is contradictory regarding the impact of the recognised risk factors of PCO. The aim of this review is firstly to collate the known biochemical pathways that lead to PCO development, providing an up-to-date chronological overview from surgery to established PCO formation. Secondly, the risk factors of PCO are evaluated, focussing on the impact of IOLs’ properties. Finally, the latest experimental model designs used in PCO research are discussed to demonstrate the ongoing development of clinical PCO models, the efficacy of newly developed IOL technology, and potential therapeutic interventions. This review will contribute to current PCO literature by presenting an updated overview of the known developmental pathways of PCO, an evaluation of the impact of the risk factors underlying its development, and the latest experimental models used to investigate PCO. Furthermore, the review should provide developmental routes for research into the investigation of potential therapeutic interventions and improvements in IOL design in the aid of preventing PCO for new and existing patients.

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.

A comparison of posterior capsular opacification after implantation of three different hydrophobic square edge intraocular lenses

Purpose

To compare the posterior capsular opacification (PCO) after implantation of three types of hydrophobic square edge intraocular lenses (IOLs).

Methods

A single-center, hospital-based, cross-sectional, observational study was conducted wherein patients with senile cataract who had undergone phacoemulsification by a single surgeon, with the implantation of three different types of square edge, hydrophobic IOLs [Group 1: enVista, Bausch and Lomb; Group 2: Tecnis 1 ZCBOO, AMO and Group 3: Acrysof IQ SN60WF, Alcon], and followed up for 12 months were included. The PCO was graded clinically and scored using the EPCO 2000 software.

Results

90 eyes of 90 patients were included. There was no significant difference in the PCO with respect to age, gender, or associated presence of systemic disease. The median PCO score was 0.035, 0.045 and 0.085 in groups 1, 2 and 3, respectively. The PCO grade and score differences between the groups were statistically significant with P < 0.001.

Conclusion

The hydrophobic nature and posterior square edge design in the IOLs probably contributed to the minimal visually-significant PCO in all the groups, in our study. However, PCO scores were lesser in the square edge IOLs having a continuous 360 degrees posterior enhanced barrier, than those without this feature.

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.

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.

A pilot study to determine if intraocular lens choice at the time of cataract surgery has an impact on patient-reported driving habits

PURPOSE

To determine if intraocular lens (IOL) choice at the time of cataract surgery affects driving habits.

MATERIALS AND METHODS

Pseudophakes who were 28-35 months postbilateral cataract surgery with one of two contemporary one-piece hydrophobic acrylic IOLs (SN60WF or ZCB00) were asked to complete the Driving Habits Questionnaire, a validated instrument for determining self-reported driving status, frequency, and difficulty. To determine if there were any differences in driving habits between the two groups, t-tests and χ (2) tests were used.

RESULTS

Of 90 respondents, 72 (40 SN60WF and 32 ZCB00) were still active drivers. The SN60WF-implanted subjects were less likely to drive at the same speed or faster than the general flow of traffic, less likely to rate their quality of driving as average/above average, less likely to have traveled beyond their immediate neighborhood, less likely to drive at night, more likely to have moderate-to-severe difficulty driving at night, and more likely to have self-reported road traffic accidents. The differences did not reach statistical significance.

CONCLUSION

Changes in patients' driving habits 2-3 years after cataract surgery may be associated with the type of IOL implanted. A larger study, powered to demonstrate statistical significance, is needed to verify the trends identified in this pilot study and discover possible contributing factors.

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.

Intracameral mydriatics in phacoemulsification cataract surgery -- a 6-year follow-up

PURPOSE

To evaluate the long-term safety of intracameral mydriatics (ICM) in phacoemulsification cataract surgery compared with conventional topical mydriatics (TM).

METHODS

A total of 45 patients were examined 6 years after phacoemulsification cataract surgery. The patients had previously participated in a prospective randomized double-blind study including 60 patients, operated with either ICM or TM. The follow-up included best-corrected visual acuity (BCVA), intraocular pressure (IOP), grade of posterior capsule opacification (PCO), YAG laser capsulotomy rate, pupil size, corneal thickness and endothelial morphology.

RESULTS

No differences in postoperative BCVA, IOP, pupil size, PCO or YAG rate were observed between the groups. Endothelial cell loss, endothelial morphology and corneal thickness were also equivalent.

CONCLUSIONS

Intracameral mydriatics is a safe alternative to topical mydriatics in phacoemulsification cataract surgery with no long-term disadvantages at 6-year follow-up.

Comparison of clinical efficacy: Nd:YAG laser rates after implantation of AcrySof® SN60WF, Akreos® AO-MI60 and Hoya® YA-60BB

PURPOSE

To compare Nd:YAG laser rates following implantation of AcrySof(®) SN60WF (Alcon), Akreos(®) AO-MI60 (Baush & Lomb), and Hoya(®) YA-60BB (Hoya) intraocular lenses.

METHODS

This retrospective study was conducted at three French centers with each implanting at least two of the three implants. Included patients had undergone uncomplicated cataract surgery with at least 3 years of follow-up. Records of patients implanted with one of the three IOL's were drawn randomly from the surgical logs. Postoperative data were obtained from the medical records of either the surgeon or the referring physician. Time elapsing until Nd:YAG laser was analysed using Kaplan-Meier survival curves.

RESULTS

Three hundred eyes were implanted (AcrySof(®) 126, Akreos(®) 89, and Hoya(®) 85). AcrySof(®) recipients were the youngest (AcrySof(®) 72.1, Akreos(®) 76.4, and Hoya(®) 75.2 years of age: P=0.0007). The sex ratio was 4:6 male:female. Follow-up was longest for Hoya eyes (AcrySof(®) 29.4, Akreos(®) 24.6 and Hoya(®) 34.6 months; P=0.0002). Eyes implanted with AcrySof(®) had 1.74 times less chance of Nd:YAG laser treatment than Hoya eyes (P=0.0327) and 3.50 times less than Akreos(®) eyes (P<0.0001). The results remained unchanged when the analysis was restricted to events in the first 24 months (Risk Ratios: Hoya(®)=2.64: P=0.02; and Akreos(®)=4.22: P=0.0001). Adjustment on unbalanced confounding variables did not alter the results.

CONCLUSIONS

Eyes with AcrySof(®) implants required significantly fewer Nd:YAG laser capsulotomies than those with Hoya(®) and Akreos(®) implants and were therefore less subject to Nd:YAG laser treatment complications, thus ensuring better vision at the lowest cost.

Cost of cataract surgery after implantation of three intraocular lenses

Background:

Posterior capsule opacification is one of the most frequent adverse events following cataract surgery. This manuscript reports the lifetime cost of complications linked to posterior capsule opacification using three types of intraocular lens with square edges.

Methods:

Costs were estimated from a retrospective study of patients who underwent cataract surgery and data from the literature. The lenses studied were hydrophobic acrylic (SA60AT and AR40E) and hydrophilic acrylic (XL-Stabi) lenses with square edges. The frequency of Nd-Yag laser capsulotomies after 4 years’ survival was estimated by two methods: the first involved linear adjustment of the rate at 5 and 6 years follow-up and then application of a constant rate after 6 years; the second involved linear adjustment after 5 years follow-up. The economic perspective was that of the French Sickness Fund.

Results:

After 3 years’ follow-up the percentage of patients who had not undergone laser Nd-Yag capsulotomy was 86.9% with SA60AT, 76.6% with AR40E and 54.6% with XL-Stabi lenses (p < 0.001). The total cost of capsulotomy and management of complications per patient lifetime was estimated to be €90.5 for SA60AT, €189.5 for AR40E and €288.0 for XL-Stabi lenses by the first extrapolation method. With the second method of extrapolation the costs were €94.8, €200.0 and €300.2, respectively.

Interpretation:

Lower costs for cataract surgery and management of related complications were observed with the two hydrophobic acrylic lenses; the lowest costs were observed with SA60AT lenses as they were associated with fewer Nd-Yag laser capsulotomies.