A systematic overview of the incidence of posterior capsule opacification

Evaluation of change in the contact of IOL with the posterior capsule with respect to the orientation of haptics of the IOL using intraoperative spectral domain optical coherence tomography

PURPOSE

To study change in the contact of intraocular lens (IOL) with the posterior capsule with respect to the vertical versus horizontal orientation of the haptic-optic junction of the IOL using intraoperative spectral domain optical coherence tomography (SD-OCT).

METHODS

Fifty eyes of 50 patients with senile immature cataract underwent topical phacoemulsification procedure with implantation of a monofocal IOL by a single experienced surgeon. The Rescan 700 SD-OCT system was used for intraoperative imaging. These patients were imaged using intraoperative SD-OCT after implantation of IOL, with the haptics oriented horizontally and then vertically.

RESULTS

The vertical height between the posterior surface of the lens capsule and the posterior surface of IOL reduced significantly when the haptics were oriented vertically compared to horizontal orientation. This difference was found on analyzing both vertical as well as horizontal axis scans.

CONCLUSION

We found a greater contact between the posterior capsule and the posterior surface of IOL, with the haptic optic junction of the IOL oriented vertically. This study also suggests the need for newer toric IOL designs which allow vertical orientation of haptics, leading to better contact between IOL and the bag.

Long-Term Assessment of PC-IOL Optic Apposition in Surface-Modified IOL and Its Impact on Nd:YAG Capsulotomy Rate and Visual Quality

PURPOSE

To assess apposition of posterior capsule (PC) to intraocular lens (IOL) optic in ultraviolet (UV)/ozone surface modified IOL and its impact on neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy rate and visual quality.

DESIGN

Prospective interventional case series.

METHODS

The study enrolled 100 eyes implanted with UV/ozone surface modified hydrophobic acrylic IOL during phacoemulsification. The primary outcome measure was PC-optic apposition on anterior segment optical coherence tomography (ASOCT). Secondary outcomes were Nd:YAG capsulotomy and visual quality (ray-tracing aberrometry). Follow-up was performed on postoperative day (POD) 1, at 1, 3, and 6 months, and 1 and 2 years.

RESULTS

Complete PC-optic apposition was observed in 4% of cases on POD1, which increased to 75% at 2 years. PC configuration in cases with PC-optic non-apposition was smooth (34.4%) or wavy (65.6%) on ASOCT; initial smooth PC was associated with significantly higher incidence of PC-optic apposition at 2 years (p=0.028). At 2 years, visual quality was significantly better in cases with complete PC-optic apposition in terms of Strehl ratio (P = .029), modulation transfer function (MTF) (P = 0.016), root mean square (RMS) aberrations (P = .024) and higher order aberrations (HOAs) (P = 0.043). A significant positive correlation was observed between height of interface fluid and total RMS (Pearson correlation coefficient 0.221; P = .027) and HOAs (Pearson correlation coefficient 0.198; P = .048). PCO developed in 7% of cases (7/100); of these, 6 cases had persistent PC-optic non-apposition. Nd:YAG laser capsulotomy was required in 3% (3/100) cases; all of these cases had persistent PC-optic non-apposition.

CONCLUSIONS

Long-term complete PC-optic apposition was observed in 75% of patients implanted with UV/ozone surface-modified IOLs. Complete PC-optic apposition is associated with lower Nd:YAG capsulotomy rate and superior visual quality.

Influence of Lens Power on IOL/Posterior Lens Capsule Interactions and IOL's PCO Potential

Purpose

Severely myopic eyes have been associated with high posterior capsule opacification (PCO) incidence. Although it has been reported that myopic eyes have weaker or more delayed capsule adhesion than emmetropic eyes, it is unclear whether/how dioptric power and posterior curvature of IOLs affect IOLs' affinity for the posterior lens capsule (PLC) and their PCO potential.

Methods

To investigate this, acrylic foldable IOLs with increasing dioptric power of 6.0D (for high myopia), 20.0D, and 30.0D (for low/non-myopia) were tested on their binding affinity toward PLC and their ability to inhibit the proliferation and infiltration of lens epithelial cells (LECs) using an in vitro simulated human PLC (sPLC) model.

Results

We found that IOL power and posterior radius of curvature (PRC) had significant impacts on IOL/sPLC adhesion forces, which are in the following order: 20.0D ≈ 30.0D > 6.0D. Optical coherence tomography (OCT) images showed that loose binding between 6.0D IOLs and sPLC contributed to larger interface spaces and significantly greater LEC infiltration, proliferation, metabolic activity, and transdifferentiation compared to 20.0D and 30.0D IOLs. Statistical analyses showed that IOLs' PRC may have a substantial influence on IOL/sPLC physical interactions, LEC responses, and PCO incidence.

Conclusions

The overall results suggest that the high PRC of low-diopter (6.0D) IOLs reduces their binding affinity toward the PLC, facilitates LEC reactions, thus causes high PCO incidence in myopic eyes. These findings strongly support that a new design to increase IOL posterior surfaces' PLC affinity may reduce PCO potential and increase safety for myopic patients.

Evaluation of Intraocular Pressure, Refraction, Anterior Chamber Depth, Macular Thickness, and Specular Microscopy Post-Neodymium-Doped Yttrium-Aluminum-Garnet Laser in Patients With Posterior Capsular Opacification

Background Cataract is the leading cause of blindness globally, particularly in India. Despite advancements in surgical techniques, postoperative complications remain common, with posterior capsular opacification (PCO) being the most frequent issue. Although neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy is recommended for managing PCO, it is associated with various side effects. This study aimed to evaluate the effects of Nd:YAG laser capsulotomy on intraocular pressure (IOP), visual acuity, anterior chamber depth (ACD), macular thickness, and corneal endothelium in Indian patients. Methodology This prospective, hospital-based study was conducted in the ophthalmology department at a tertiary care center in western Maharashtra from September 2022 to June 2024. Approval from the Institutional Scientific and Ethics Committee was obtained before commencing the research. In the study, 72 eyes from 72 patients with PCO following uncomplicated cataract surgery who were undergoing Nd:YAG laser capsulotomy were included, whereas patients with corneal pathology, retinal pathology, complicated cataract surgery, or trauma were excluded. Patients with active uveitis, non-compliant patients, and those unwilling to undergo the procedure were also excluded. Written informed consent was obtained from each patient. Data were managed in Microsoft Excel, and statistical analysis was conducted using the SPSS 26.0 software. As the continuous variables exhibited skewed distribution, the Wilcoxon test was employed to assess categorical variables such as the significance of IOP and endothelial cell differences over time. A significance level of 5% was assumed, with a p-value below 0.05 considered significant. Results The mean age of patients who underwent Nd:YAG capsulotomy was 64 years, with a female predominance of 37 (51.4%). In the study, 37 (51.4%) patients had their left eye treated, while 35 (48.6%) had their right eye treated. Overall, 45 (62.5%) patients had a baseline best-corrected visual acuity (BCVA) of 6/24-6/12. At one hour post-procedure, 46 (63.9%) patients in Group II had a BCVA of 6/24-6/12, and by one week after treatment, 53 (73.6%) patients had a BCVA of >6/12-6/6. ACD was normal in all patients before and after the procedure. Two patients developed macular edema at one hour and one week after the procedure. The mean IOP at baseline, one hour, and one week were 13.5, 13.86, and 13.69 mmHg, respectively. A significant increase in IOP was observed at one hour post-procedure, along with a significant decrease in endothelial cell count compared to baseline, which also persisted at one week. Conclusions Patients undergoing Nd:YAG capsulotomy experienced an initial rise in IOP, followed by a subsequent decline. Improved visual acuity was noted in most patients at one hour and by one week. A significant decline in endothelial cell count was observed following the procedure, and macular edema was noted in two patients. Anterior chamber reaction was observed in nearly all patients, which decreased by one week. With no change in ACD following the procedure up to one week, ocular refraction was not significantly impacted in the short term. Therefore, further large-scale intervention studies are needed to evaluate the effects of Nd:YAG laser capsulotomy size and the energy used on refractive error and post-procedure complications, as well as to explore the long-term effects on IOP.

Study of the relationship between the severity of posterior capsular opacification detected by objective detection techniques and visual acuity

PURPOSE

To explore the severity of posterior capsule opacification (PCO) using objective detection techniques and its relationship with visual acuity.

SETTING

The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.

DESIGN

Prospective cohort study.

METHODS

All patients underwent slitlamp examination, intraocular pressure (IOP) measurement, and corrected distance visual acuity (CDVA) testing before Nd:YAG laser capsulotomy, and examination, after fully dilated, with: IOLMaster 700, optical coherence tomography (OCT), Sirius Topographer (CSO) anterior segment analysis, and color fundus photography (CFP). CDVA and IOP were taken post treatment. Thickness and density of the posterior capsule, CFP quality (CFPQ) and OCT signal strength (OCTSS) were recorded. Analysis used Spearman correlation, heatmaps, and receiver operating characteristic curves.

RESULTS

83 eyes in 78 patients were included in this study. Spearman correlation analysis revealed correlations between pretreatment CDVA and IOLMaster 700 PCO thickness (MT), IOLMaster 700 cumulative effect (MCE), Sirius PCO thickness (ST), Sirius maximum density (SMD), Sirius cumulative effect (SCE), OCTSS, and CFPQ (correlation coefficients were 0.500, 0.484, 0.465, -0.256, 0.317, -0.442, -0.412, all P < .05). The improvement of vision acuity (ImpVA) showed correlations with MT, MCE, ST, SCE, OCTSS, and CFPQ (correlation coefficients were -0.452, -0.471, -0.346, -0.278, 0.320, 0.381, all P < .05). For ImpVA, the predictive ability of IOLMaster 700 was superior to Sirius, and the joint model was significantly better than single factors.

CONCLUSIONS

Posterior capsule thickness and cumulative effect were reliable indicators for evaluating PCO. Compared with Sirius, the IOLMaster 700 demonstrated superior predictive ability and higher correlation.

Human Primary Lens Epithelial Cultures on Basal Laminas Studied by Synchrotron-Based FTIR Microspectroscopy for Understanding Posterior Capsular Opacification

Human primary lens epithelial cultures serve as an in vitro model for posterior capsular opacification (PCO) formation. PCO occurs when residual lens epithelial cells (LECs) migrate and proliferate after cataract surgery, differentiating into fibroblastic and lens fiber-like cells. This study aims to show and compare the bio-macromolecular profiles of primary LEC cultures and postoperative lens epithelia LECs on basal laminas (bls), while also analyzing bls and cultured LECs separately. Using synchrotron radiation-based Fourier transform infrared (SR-FTIR) (Bruker, Karlsruhe, Germany) microspectroscopy at the Spanish synchrotron light source ALBA, we observed that the SR-FTIR measurements were predominantly influenced by the strong collagen absorbance of the bls. Cultured LECs on bls showed a higher collagen contribution, indicated by higher vas CH3, CH2 and CH3 wagging and deformation, and the C-N stretching of collagen. In contrast, postoperative LECs on bls showed a higher cell contribution, indicated by the vsym CH2 peak and the ratio between vas CH2 and vas CH3 peaks. The primary difference revealed using SR-FTIR is the greater LEC contribution in spectra recorded from postoperative lens epithelia compared to cultured LECs on bls. IR spectra for bl, cultured LECs and postoperative lens epithelia could be valuable for future research.

Refractive Lens Exchange: A Review

In recent decades, technical advancements in lens surgery have considerably improved safety and refractive outcomes. This has led to a much broader range of indications for refractive lens exchange (RLE). Effective restoration of uncorrected distance and near visual acuity is possible with modern presbyopia correcting intraocular lenses (IOLs). Hyperopic patients who are fully presbyopic were identified as ideal candidates for RLE. For myopic patients, an increased risk of retinal detachment has been reported, which leads to a higher threshold to perform RLE in this patient group. The most frequent postoperative complications include posterior capsular opacification, deviation from the target refraction and cystoid macular edema. Thus, adequate planning of surgery, careful patient selection, as well as comprehensive counseling are crucial for successful RLE.

Neodymium-doped yttrium aluminum garnet (Nd: YAG) laser treatment in ophthalmology: a review of the most common procedures Capsulotomy and Iridotomy

Nowadays, lasers are used in various medical fields. Ophthalmology was the first medical specialty to utilize lasers in patient treatment and still remains the leading medical field that uses laser energy for both therapeutic and diagnostic purposes. The neodymium: yttrium-aluminum-garnet (Nd: YAG) laser is one of the most common lasers used in ophthalmology. It is a solid-state laser with a wavelength of 1064 nm that works on the principle of photodisruption. Since its introduction in ophthalmology over 40 years ago, it has found various applications, mainly for procedures where cutting or disruption of ocular tissue is required. Compared to surgical alternatives, the use of Nd: YAG lasers on ocular tissue is minimally invasive. In this review, we focus on the two most common ophthalmic applications of Nd: YAG laser - laser peripheral iridotomy and posterior capsulotomy. The history of the techniques, current trends, potential complications, and the prognosis for future use is discussed.

A Novel 3D High Resolution Imaging Method Using Correlative X-Ray and Electron Microscopy to Study Neodymium-Doped Yttrium Aluminum Garnet Laser-Induced Defects in Intraocular Lenses

INTRODUCTION

Cataract extraction is the most frequently performed ophthalmological procedure worldwide. Posterior capsule opacification remains the most common consequence after cataract surgery and can lead to deterioration of the visual performance with cloudy, blurred vision and halo, glare effects. Neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy is the gold standard treatment and a very effective, safe and fast procedure in removing the cloudy posterior capsule. Damaging the intraocular lens (IOL) during the treatment may occur due to wrong focus of the laser beam. These YAG-pits may lead to a permanent impairment of the visual quality.

METHODS

In an experimental study, we intentionally induced YAG pits in hydrophilic and hydrophobic acrylic IOLs using a photodisruption laser with 2.6 mJ. This experimental study established a novel 3D imaging method using correlative X-ray and scanning electron microscopy (SEM) to characterize these damages. By integrating the information obtained from both X-ray microscopy and SEM, a comprehensive picture of the materials structure and performance could be established.

RESULTS

It could be revealed that although the exact same energies were used to all samples, the observed defects in the tested lenses showed severe differences in shape and depth. While YAG pits in hydrophilic samples range from 100 to 180 µm depth with a round shape tip, very sharp tipped defects up to 250 µm in depth were found in hydrophobic samples. In all samples, particles/fragments of the IOL material were found on the surface that were blasted out as a result of the laser shelling.

CONCLUSION

Defects in hydrophilic and hydrophobic acrylic materials differ. Material particles can detach from the IOL and were found on the surface of the samples. The results of the laboratory study illustrate the importance of a precise and careful approach to Nd:YAG capsulotomy in order to avoid permanent damage to the IOL. The use of an appropriate contact glass and posterior offset setting to increase safety should be carried out routinely.

How Safe is Nd: YAG Laser Capsulotomy in Patients with Uveitis? Outcomes of a Long-Term Study

Purpose

To study the outcomes and complications of Nd: YAG laser capsulotomy in patients with uveitis.

Methods

This study retrospectively evaluated outcomes of Nd: YAG laser capsulotomy in 260 eyes of 260 patients with uveitis. The main indications for performing capsulotomy were a visually significant posterior capsule opacification (PCO) and inability to visualize the posterior segment. The presence of 5 or <5 cells per high-power field in the anterior chamber for a minimum period of 3 months was a prerequisite for capsulotomy.

Results

The mean age of patients was 52.8 ± 11.3 (range, 38-75 years). The incidence of PCO in the study was 22.4%. The mean follow-up was 21.5 ± 11.3 months postcapsulotomy. The mean best-corrected visual acuity (BCVA) improved in 161 (62%) eyes after capsulotomy. The BCVA remained stable in 50 (19.3%) eyes due to preexisting ocular pathology involving the macular area. There was worsening of BCVA in 49 (18.8%) eyes. The main causes of worsening of BCVA were sustained intraocular pressure (IOP) elevation (n = 13%), cystoid macular edema (CME) (n = 8.5%), and retinal detachment (RD) (n = 2.7%), respectively. Ninety-one percent (n = 20) of patients with CME had exaggerated postlaser inflammation and recurrent uveitis. The presence of posterior vitreous detachment (PVD) and higher laser energy levels were significant risk factors for RD.

Conclusions

Nd: YAG laser capsulotomy in patients with uveitis may be associated with complications. Inflammation and IOP should be well controlled before initiating laser capsulotomy. Capsulotomy should be performed with caution in patients with preexisting PVD.

Analysis of the capsular bend in posterior capsular opacification using anterior segment optical coherence tomography

PURPOSE

To investigate the link between the capsular bend and the morphological types and characteristics of posterior capsular opacification (PCO) using anterior segment optical coherence tomography.

METHODS

Thirty eyes with PCO were examined, and three types of PCO were identified: pearl, fibrosis, and mixed. We assessed anterior capsular overlap, intraocular lens-capsule adhesion, and capsular bending. In addition to measuring the intraocular lens-posterior capsule distance and capsule bending angle (CBA), the PCO parameters (area, density, and score at 6-, 5-, and 3-mm intraocular lens optic regions) were recorded. The associations between capsular bend and PCO type and characteristics were investigated. A control group of 12 eyes without PCO was used to compare the study variables.

RESULTS

With p values greater than 0.001, there was a statistically significant difference in the mean PCO area and score at the 6-, 5-, and 3-mm optic zones in different PCO types, with the pearl type having the highest value, followed by the mixed type, and finally the fibrosis type. The PCO group had a significantly higher mean CBA than the control group (P = 0.001). CBA was positively related to intraocular lens-posterior capsule distance, PCO area, and PCO score at the 6-, 5-, and 3-mm zones (P = 0.001). The receiver operating characteristic curve's cut-off point for CBA was 96.85° when comparing PCO cases to controls. Partial overlap and incomplete adhesion were statistically more common in the PCO eyes than in the control (P = 0.001, 0.003, respectively).

CONCLUSION

PCO types and CBA have a strong relationship with PCO score and intraocular lens-posterior capsule space. In PCO's eyes, CBA has a cut-off value of 96.85°.

Glutaredoxin 1 protects lens epithelial cells from epithelial-mesenchymal transition by preventing casein kinase 1α S-glutathionylation during posterior capsular opacification

Oxidative stress drives protein S-glutathionylation, which regulates the structure and function of target proteins and is implicated in the pathogenesis of many diseases. Glutaredoxin 1 (Grx1), a cytoplasmic deglutathionylating enzyme, maintains a reducing environment within the cell under various conditions by reversing S-glutathionylation. Grx1 performs a wide range of antioxidant activities in the lens and prevents protein-thiol mixed disulfide accumulation, reducing protein-protein aggregation, insolubilization, and apoptosis of lens epithelial cells. Oxidative stress is related to epithelial-mesenchymal transition (EMT) during posterior capsular opacification (PCO). However, whether Grx1-regulated protein S-glutathionylation plays an essential role in PCO remains unclear. In this study, we revealed that Grx1 expression was decreased in mice following cataract surgery. Furthermore, the absence of Grx1 elevated oxidative stress and protein S-glutathionylation and aggravated EMT in both in vitro and in vivo models. Concurrently, these results could be reversed by Grx1 overexpression. Notably, liquid chromatography-tandem mass spectrometry results showed that casein kinase 1α (CK1α) was susceptible to S-glutathionylation under oxidative stress, and CK1α S-glutathionylation (CK1α-SSG) was mediated at Cys249. The absence of Grx1 upregulated CK1α-SSG, subsequently decreasing the CK1α-induced phosphorylation of β-catenin at Ser45. The consequential downregulation of degradative β-catenin and upregulation of its nuclear translocation activated the Wnt/β-catenin signaling pathway and aggravated EMT. In conclusion, the downregulated expression of Grx1 in mice following cataract surgery aggravated EMT by upregulating the extent of CK1α-SSG. To the best of our knowledge, our study is the first to report how S-glutathionylation regulates CK1α activity under oxidative stress.

Nd:YAG laser capsulotomy rates in the Netherlands: practice variation and association with physician practice styles

PURPOSE

To determine the practice variation in the rate of Nd:YAG laser capsulotomy within 1 year after cataract surgery and to identify possible associations with physician practice styles.

SETTING

All hospitals and private clinics in the Netherlands.

DESIGN

Retrospective observational study.

METHODS

In the national medical claims database, we identified all laser capsulotomies performed in the Netherlands within a year after cataract surgery in the years 2016 and 2017. Centers with the lowest and highest percentages of Nd:YAG laser capsulotomies were interviewed on their physician practice styles related to the development of posterior capsule opacification.

RESULTS

The incidence of Nd:YAG laser capsulotomy varied between 1.2% and 26.0% in 2016 (median 5.0%) and between 0.9% and 22.7% in 2017 (median 5.0%). The rate of capsulotomy was highly consistent over time for each center (Pearson correlation coefficient, 0.89, P < .001). In general, ophthalmology centers with a high rate of Nd:YAG laser capsulotomy more often did not (routinely) polish the posterior lens capsule, performed cortex removal with coaxial irrigation/aspiration (I/A, instead of bimanual), and more often used hydrophilic intraocular lenses (IOLs) (compared with only using hydrophobic IOLs).

CONCLUSIONS

We found a significant practice variation in performing Nd:YAG laser capsulotomy within 1 year after cataract surgery in the Netherlands. Routinely polishing the posterior capsule, using bimanual I/A, and the use of hydrophobic IOLs are associated with a lower incidence in Nd:YAG laser capsulotomy. Incorporating these practice styles may lower the practice variation and thus prevent added medical burden for the patient and decrease costs.

Understanding Inflammation-associated Ophthalmic Pathologies: A Novel 3D Co-culture Model of Monocyte-myofibroblast Immunomodulation

PURPOSE

Inflammation is associated with, and may be causal of, a variety of ophthalmic pathologies. These pathologies are currently difficult to model in vitro because they involve complex interactions between the innate immune system, stromal cells, and other cells that normally maintain ocular tissue homeostasis. Using transscleral drainage channel fibrosis after glaucoma surgery as an example of inflammation-associated ocular fibrosis, we have assessed a simple but novel 3D cell culture system designed to reveal the immunomodulatory impacts of ocular connective tissue cells on monocytes, a major cellular component of the circulating immune system.

METHODS

Primary human Tenon's capsule fibroblasts derived from five unrelated patients were activated into myofibroblasts in 3D collagen matrices under isometric tension, with and without exposure to an inflammatory cytokine-enhanced milieu, and co-cultured with an immortalized human monocyte cell line (THP-1 cells). Quantitative PCR analyses were performed on 8 candidate genes to assess the impacts of inflammatory cytokines on the myofibroblasts and the monocytes in mono-cultures and compared to cells in co-culture to clearly distinguish any co-culture-induced impacts on gene expression.

RESULTS

Our data indicate that both Tenon's capsule myofibroblasts in 3D mono-culture and THP-1 monocytes in suspension mono-culture were responsive to inflammatory cytokine stimuli. Co-culture with Tenon's capsule myofibroblasts significantly modulated the gene expression responses of THP-1 monocytes to inflammatory cytokine stimulation, indicative of an immunomodulatory "feedback" system between these cell types.

CONCLUSION

Our findings provide proof of principle for the use of simple 3D co-culture systems as a means to enhance our understanding of ocular stromal cell interactions with cells of the innate immune system and to provide more informative in vitro models of inflammation-associated ophthalmic pathologies.

Observation of Cyclosporin A: Sustained Release Intraocular Lens Implantation in Rabbit Eyes

PURPOSE

To observe the performance of cyclosporine A (CsA)-loaded intraocular lens (IOLs) implanted into rabbit eyes.

METHODS

To prepare a PLGA-based CsA-sustained release IOLs and study the in vitro drug release. Forty-two New Zealand white rabbits were randomly and equally divided into three groups, and all right eyes underwent phacoemulsification. In group A, a common polymethylmethacrylate (PMMA) IOLs was implanted, while polylactide-glycoli acid (PLGA-loaded)-PMMA-IOLs was implanted in group B, and CsA-PLGA-PMMA-IOLs was implanted in group C. All experimental eyes were examined by slit-lamp microscopy. In addition, fundoscopy and the number of corneal endothelial cells, anterior chamber flare grading, and the number of aqueous humor cells were assessed at different time points post-surgery. The wet lens capsule was weighed and histological examination was performed 6 months post-operation.

RESULTS

In the early post-operative period, the inflammatory reaction of anterior chamber in groups A and B were more severe than group C. The initial appearance of PCO in group C was much later than the other two groups (F = 68.91; p = 0.000), and PCO grade in group C was much lower than the other two groups (χ² = 36.07; p = 0.000). The mean weights of wet lens capsules in groups A and B were significantly heavier than group C (F = 134.88; p = 0.00). Histological observation showed no obvious toxic reaction in the intraocular tissues of the CsA-PLGA-PMMA-IOLs group, and the proliferation and accumulation of lens epithelial cells in groups A and B were greater than in group C.

CONCLUSION

CsA-sustained release IOLs can effectively prevent PCO in rabbit eyes without defined intraocular toxicity.

Impact of the Aging Lens and Posterior Capsular Opacification on Quantitative Autofluorescence Imaging in Age-Related Macular Degeneration

Purpose

The purpose of this study was to investigate quantitative autofluorescence (qAF8) in patients with and without early or intermediate age-related macular degeneration (AMD); to determine the impact of the aged crystalline lens and posterior capsular opacification (PCO).

Methods

In phakic and pseudophakic eyes ≥60 years, AMD status was determined by the Beckman system. PCO presence and severity was extracted from clinical records. qAF8 was calculated using custom FIJI plugins. Differences in qAF8, stratified by lens status, PCO severity, and AMD status, were analyzed using generalized estimating equations.

Results

In 210 eyes of 115 individuals (mean age = 75.7 ± 6.6 years), qAF8 was lower in intermediate AMD compared to early AMD (P = 0.05). qAF8 did not differ between phakic and pseudophakic eyes (P = 0.8909). In phakic (n = 83) and pseudophakic (n = 127) eyes considered separately, qAF8 did not differ by AMD status (P = 0.0936 and 0.3494, respectively). Qualitative review of qAF images in phakic eyes illustrated high variability. In pseudophakic eyes, qAF8 did not differ with PCO present versus absent (54.5% vs. 45.5%). Review of implanted intraocular lenses (IOLs) revealed that 43.9% were blue-filter IOLs.

Conclusions

qAF8 was not associated with AMD status, up to intermediate AMD, considering only pseudophakic eyes to avoid noisy images in phakic eyes. In pseudophakic eyes, qAF8 was not affected by PCO. Because blue-filter IOLs may reduce levels of exciting light for qAF8, future studies investigating qAF in eyes with different IOL types are needed.

Translational Relevance

To reduce variability in observational studies and clinical trials requiring qAF8, pseudophakic participants without blue-filter IOLs or advanced PCO should be preferentially enrolled.

Amphiphilic silicones to mitigate lens epithelial cell growth on intraocular lenses

Silicone intraocular lenses (IOLs) that resist lens epithelial cell (LEC) growth would greatly improve patient outcomes. Herein, amphiphilic surface modifying additives (SMAs) were incorporated into an IOL-type diphenyl silicone to reduce LEC growth without compromising opto-mechanical properties. The SMAs were poly(ethylene oxide)-silane amphiphiles (PEO-SAs) [H-Si-ODMS_m-block-PEO₈-OCH₃], comprised of a PEO segment and siloxane tether of varying lengths (m = 0, 13, and 30). These three SMAs were each blended into the addition cure diphenyl silicone at varying concentrations (5, 10, 15, 20, and 25 μmol g^-1) wherein the wt% of PEO was maintained for all SMAs at a given molar concentration. The chemical crosslinking and subsequent retention of SMAs in modified silicones was confirmed. Key material properties were assessed following equilibration in both air and aqueous environments. Silicones modified with SMAs having longer tethers (m = 13 and 30) underwent rapid and substantial water-driven restructuring of PEO to the surface to form highly hydrophilic surfaces, especially as SMA concentration increased. The % transmittance was also maintained for silicones modified with these particular SMAs. The moduli of the modified silicones were largely unchanged by the SMA and remained in the typical range for silicone IOLs. When the three SMAs were introduced at the highest concentration, modified silicones remained non-cytotoxic and LEC count and associated alpha-smooth muscle actin (α-SMA) expression decreased with increasing tether length. These results demonstrate the potential of silicones modified with PEO-SA SMAs to produce LEC-resistant IOLs.

In vitro assessment of the biocompatibility of chemically treated silicone materials with human lens epithelial cells

Cytotoxicity testing is a regulatory requirement for safety testing of new ocular implants. In vitro toxicity tests determine whether toxic chemicals are present on a material surface or leach out of the material matrix. A method of evaluating the cytotoxicity of ocular implants was developed using fluorescent viability dyes. To assess the assay’s sensitivity in detecting toxic substances on biomaterials, zinc diethydithiocarbamate (ZDEC) and benzalkonium chloride (BAK) were deposited on silicone surfaces at different concentrations. Human lens epithelial cells (HLEC) were added to the surface of these treated silicone surfaces and were assessed for viability. The viability of both the adherent and non-adherent cells was determined using confocal microscopy with, annexin V, ethidium homodimer, and calcein. Cell metabolism was also evaluated using resazurin and the release of inflammatory cytokines was quantified using a multiplex Mesoscale Discovery platform. Confocal microscopy was shown to be a sensitive assay for evaluating material toxicity, as significant toxicity (p < 0.05) from ZDEC and BAK-treated surfaces compared to the untreated silicone control was detected. Patterns of cytokine release from cells varied depending on the toxin evaluated and the toxin concentration and did not directly correlate with the reduction in cell metabolic activity measured by alamarBlue.

Foldable Bulk Anti-adhesive Polyacrylic Intraocular Lens Material Design and Fabrication for Posterior Capsule Opacification Prevention

Posterior capsular opacification (PCO) is a primary complication after phacoemulsification combined with intraocular lens (IOL) implantation, which is attributed to adhesion, proliferation, and migration of residual lens epithelial cells on IOL. Although surface hydrophilic coating is considered to be a powerful way to inhibit PCO incidence after surgery, it requires complex post-production processes, thus limiting their applicability. In comparison, bulk modification is a stable, effective, and facile IOL synthesis method for PCO prevention. Herein, a new anti-adhesive IOL material was designed and successfully synthesized by radical copolymerization of ethylene glycol phenyl ether methacrylate (EGPEMA) and 2-(2-ethoxyethoxy) ethyl acrylate (EA). The physicochemical properties of P(EGPEMA-co-EA) copolymer materials, including chemical structure, mechanical, thermal, surface, and optical properties, were analyzed by using ¹H NMR spectroscopy, FT-IR spectroscopy, tensile test, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), water contact angle measurement, and UV-vis spectroscopy. The elongation at break and the modulus of elasticity of the copolymer were tunable through the change of the composition of monomers. Compared to other components, the tensile results showed that P(EGPEMA-co-EA) materials (70% EGPEMA in mass ratio, F7) are suitable for the preparation of foldable intraocular lens with lower elastic modulus and higher elongation at break. TGA and DSC showed that the material has high thermal stability, and the glass transition temperature of F7 material is 16.1 °C. The water contact angle measurement results showed that the introduction of EA improved the hydrophilicity of the material. The percentage of transmittance of all copolymers at 400-800 nm is above 85%. Then, the biocompatibility of the materials was evaluated by in vitro assay and subcutaneous implantation. Both in vitro results and subcutaneous implantation experiments showed that the designed IOL materials exhibited a good anti-adhesion effect and no cytotoxicity. Finally, phacoemulsification and IOL intraocular implantation were performed, and the in vivo results confirmed the good PCO prevention ability as well as the biocompatibility of the new IOL materials.

Polydopamine based photodynamic coating on intraocular lens surface for safer posterior capsule opacification conquering

Intraocular lens (IOL) is the indispensable implant for cataract surgery. However, posterior capsular opacification (PCO) happens in high incidence after IOL implantation. PCO is caused by adhesion, proliferation, trans-differentiation of...

NIR-triggered drug delivery system for chemo-photothermal therapy of posterior capsule opacification

Posterior capsule opacification (PCO) is the most common complication after cataract surgery and is likely to cause the second loss of vision. Pharmacological PCO prophylaxis has been proved to be effective, yet no clinical option is available due to the lack of a suitable mode of administration. In this work, we propose a unique concept of NIR dual-triggered drug release from black phosphorus (BP)-based implantable intraocular lens (IOL) for controlled drug release and chemo-photothermal combination therapy of PCO. Here, IOL is used as a "reservoir" of doxorubicin-loaded black phosphorus (BP-DOX), and BP is used as NIR activation agent for controlled drug release and photothermal therapy. This BP-DOX integrated IOL, namely BP-DOX@IOL, shows the characteristics of good transmittance, good mechanical property, NIR dual-triggered drug release behaviors, and excellent photothermal efficacy. In vivo studies reveal that there is no PCO occurrence in rabbits' model by using BP-DOX@IOL combined NIR irradiation, which exhibits distinct superiority on inhibiting PCO than the control group (100% PCO occurrence) 28 days post-surgery. This novel IOL drug delivery system would be a promising strategy for the future clinical application for PCO prophylaxis and treatment.

Efficacy and complications of cataract surgery in high myopia

To evaluate the efficacy and complications of cataract surgery in high myopia, a comprehensive search query was conducted from January 2000 to August 2020. A total of 19 586 highly myopic eyes from 28 studies were included. Modern cataract surgery turns out efficacious in highly myopic eyes with significant improvement of visual acuity. However, phacoemulsification-related complications such as posterior capsular rupture (3.91%, 95% CI, 1.98%-6.37%), retinal detachment (1.74%, 95% CI, 1.36%-2.15%), progressed myopic traction maculopathy (5.07%, 95% CI, 1.80%-9.37%), capsular contraction syndrome (2.1%), intraocular lens dislocation (0.58%), and transient intraocular pressure elevation (28.15%, 95% CI, 20.29%-36.70%) occurred more frequently in the highly myopic population. Separate analyses were also conducted based on follow-up period. In conclusion, modern cataract surgery was effective for highly myopic cataract patients, whereas careful precautions and sufficient follow-ups were of great value because of higher incidences of intraoperative and postoperative complications.

Cataract: Advances in surgery and whether surgery remains the only treatment in future

Background

Cataract is the world's leading eye disease that causes blindness. The prevalence of cataract aged 40 years and older is approximately 11.8%-18.8%. Currently, surgery is the only way to treat cataracts.

Main Text

From early intracapsular cataract extraction to extracapsular cataract extraction, to current phacoemulsification cataract surgery, the incision ranges from 12 to 3 ​mm, and sometimes to even 1.8 ​mm or less, and the revolution in cataract surgery is ongoing. Cataract surgery has transformed from vision recovery to refractive surgery, leading to the era of refractive cataract surgery, and premium intraocular lenses (IOLs) such as toric IOLs, multifocal IOLs, and extended depth-of-focus IOLs are being increasingly used to meet the individual needs of patients. With its advantages of providing better visual acuity and causing fewer complications, phacoemulsification is currently the mainstream cataract surgery technique worldwide. However, patient expectations for the safety and accuracy of the operation are continually increasing. Femtosecond laser-assisted cataract surgery (FLACS) has entered the public's field of vision. FLACS is a combination of new laser technology and artificial intelligence to replace fine manual clear corneal incision, capsulorhexis, and nuclear pre-fragmentation, providing new alternative technologies for patients and ophthalmologists. As FLACS matures, it is being increasingly applied in complex cases; however, some think it is not cost-effective. Although more than 26 million cataract surgeries are performed each year, there is still a gap in the prevalence of cataracts, especially in developing countries. Although cataract surgery is a nearly ideal procedure and complications are manageable, both patients and doctors dream of using drugs to cure cataracts. Is surgery really the only way to treat cataracts in the future? It has been verified by animal experiments that lanosterol therapy in rabbits and dogs could make cataract severity alleviated and lens transparency partially recovered. Although there is still much to learn about cataract reversal, this groundbreaking work provided a new strategy for the prevention and treatment of cataracts.

Conclusions

Although cataract surgery is nearly ideal, it is still insufficient, we expect the prospects for cataract drugs to be bright.

Indocyanine Green Reduces the Viability of Human Lens Epithelial Cells and Promotes Cytolysis: An Ex Vivo Study

Purpose

To investigate the effects of indocyanine green (ICG) solution on the viability and cytolysis of human lens epithelial cells ex vivo.

Methods

A total of 200 pieces of anterior capsules were obtained during cataract surgery, and 110 pieces of the anterior capsules were randomly divided into five groups and treated by immersion in different concentrations of ICG solution. The remaining 90 anterior capsules were also divided into five groups and treated with a combination of drug immersion and washing in balanced salt solution. Electron microscopy and trypan blue and eosin stains were used to analyze the cells. Percentage of dead, shedding, or living lens epithelial cells was estimated and used to demonstrate effects of the ICG on viability and cytolysis.

Results

Compared with the control group, the percentage of dead and shedding lens epithelial cells increased while the percentage of living lens epithelial cells decreased in all the immersion groups. In the washing groups, the percentage of the living lens epithelial cells was 63.42% ± 2.49%, 54.04% ± 1.84%, 43.51% ± 2.63%, 29.21% ± 2.40%, and 15.73% ± 1.61% for the five groups and reflected a concentration–effect relationship. Electron microscopy showed that the higher the concentration of the ICG solution, the more severe the destruction of the lens epithelial cell structure.

Conclusions

ICG could reduce the viability of the lens epithelial cells and promote cell cytolysis.

Translational Relevance

Our study showed that ICG could directly reduce the viability of the lens epithelial cells in a concentration-dependent fashion, which can theoretically reduce the incidence of posterior capsule opacification.

The Role of Optical Coherence Tomography Signal Strength in the Diagnosis and Follow-up of Patients with Posterior Capsular Opacification Treated with Nd:YAG Laser Capsulotomy

Objectives:

To investigate the relationship between optical coherence tomography (OCT) signal strength (SS) and visual acuity in patients with posterior capsule opacification (PCO) and evaluate the effect of PCO on retinal thickness measurements.

Materials and Methods:

Forty-one eyes of 35 patients who were diagnosed with PCO were included in the study. Patients with any anterior or posterior segment pathology other than PCO were excluded. After ophthalmologic examination, pupil dilation was induced using 0.5% tropicamide and OCT images were acquired. The assessment was repeated 1 month after Nd:YAG laser capsulotomy and postoperative values were compared with baseline values.

Results:

The patients’ mean best corrected visual acuity (BCVA) was 0.28±0.13 preoperatively and 0.78±0.09 postoperatively (p<0.0001). Strong positive correlations were observed between BCVA and SS both pre- and postoperatively (p<0.0001 and p=0.01, respectively). Central retinal thickness (CRT) and SS increased significantly postoperatively (p<0.0001 for both). OCT SS and CRT were strongly correlated preoperatively (p=0.001) but not postoperatively (p=0.46).

Conclusion:

OCT SS correlates with visual acuity in patients with PCO, and PCO can affect the accuracy of objective data obtained with OCT.

Intraocular lens optic edge design for the prevention of posterior capsule opacification after cataract surgery

BACKGROUND

Posterior capsule opacification (PCO) is a clouding of the posterior part of the lens capsule, a skin-like transparent structure, which surrounds the crystalline lens in the human eye. PCO is the most common postoperative complication following modern cataract surgery with implantation of a posterior chamber intraocular lens (IOL). The main symptoms of PCO are a decrease in visual acuity, 'cloudy', blurred vision and reduced contrast sensitivity. PCO is treated with a neodymium:YAG (Nd:YAG) laser to create a small opening in the opaque capsule and regain a clear central visual axis. This capsulotomy might cause further ocular complications, such as raised intraocular pressure or swelling of the central retina (macular oedema). This procedure is also a significant financial burden for health care systems worldwide. In recent decades, there have been advances in the selection of IOL materials and optimisation of IOL designs to help prevent PCO formation after cataract surgery. These include changes to the side structures holding the lens in the centre of the lens capsule bag, called IOL haptics, and IOL optic edge designs.

OBJECTIVES

To compare the effects of different IOL optic edge designs on PCO after cataract surgery.

SEARCH METHODS

We searched CENTRAL, Ovid MEDLINE, Ovid Embase, Latin American and Caribbean Health Sciences Literature Database (LILACS), the ISRCTN registry, ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) up to 17 November 2020.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared different types of IOL optic edge design. Our prespecified primary outcome was the proportion of eyes with Nd:YAG capsulotomy one year after surgery. Secondary outcomes included PCO score, best-corrected distance visual acuity (BCDVA) and quality of life score at one year. Due to availability of important long-term data, we also presented data at longer-term follow-up which is a post hoc change to our protocol.

DATA COLLECTION AND ANALYSIS

We used standard methods expected by Cochrane and the GRADE approach to assess the certainty of the evidence.

MAIN RESULTS

We included 10 studies (1065 people, 1834 eyes) that compared sharp- and round-edged IOLs. Eight of these studies were within-person studies whereby one eye received a sharp-edged IOL and the fellow eye a round-edged IOL. The IOL materials were acrylic (2 studies), silicone (4 studies), polymethyl methacrylate (PMMA, 3 studies) and different materials (1 study). The studies were conducted in Austria, Germany, India, Japan, Sweden and the UK. Five studies were at high risk of bias in at least one domain. We judged two studies to be at low risk of bias in all domains. There were few cases of Nd:YAG capsulotomy at one year (primary outcome): 1/371 in sharp-edged and 4/371 in round-edged groups. The effect estimate was in favour of sharp-edged IOLs but the confidence intervals were very wide and compatible with higher or lower chance of Nd:YAG capsulotomy in sharp-edged compared with round-edged lenses (Peto odds ratio (OR) 0.30, 95% CI 0.05 to 1.74; I² = 0%; 6 studies, 742 eyes). This corresponds to seven fewer cases of Nd:YAG capsulotomy per 1000 sharp-edged IOLs inserted compared with round-edged IOLs (95% CI 9 fewer to 7 more). We judged this as low-certainty evidence, downgrading for imprecision and risk of bias. A similar reduced risk of Nd:YAG capsulotomy in sharp-edge compared with round-edge IOLs was seen at two, three and five years but as the number of Nd:YAG capsulotomy events increased with longer follow-up this effect was more precisely measured at longer follow-up: two years, risk ratio (RR) 0.35 (0.16 to 0.80); 703 eyes (6 studies); 89 fewer cases per 1000; three years, RR 0.21 (0.11 to 0.41); 538 eyes (6 studies); 170 fewer cases per 1000; five years, RR 0.21 (0.10 to 0.45); 306 eyes (4 studies); 331 fewer cases per 1000. Data at 9 years and 12 years were only available from one study. All studies reported a PCO score. Four studies reported the AQUA (Automated Quantification of After-Cataract) score, four studies reported the EPCO (Evaluation of PCO) score and two studies reported another method of quantifying PCO. It was not possible to pool these data due to the way they were reported, but all studies consistently reported a statistically significant lower average PCO score (of the order of 0.5 to 3 units) with sharp-edged IOLs compared with round-edged IOLs. We judged this to be moderate-certainty evidence downgrading for risk of bias. The logMAR visual acuity score was lower (better) in eyes that received a sharp-edged IOL but the difference was small and likely to be clinically unimportant at one year (mean difference (MD) -0.06 logMAR, 95% CI -0.12 to 0; 2 studies, 153 eyes; low-certainty evidence). Similar effects were seen at longer follow-up periods but non-statistically significant data were less fully reported: two years MD -0.01 logMAR (-0.05 to 0.02); 2 studies, 311 eyes; three years MD -0.09 logMAR (-0.22 to 0.03); 2 studies, 117 eyes; data at five years only available from one study. None of the studies reported quality of life. Very low-certainty evidence on adverse events did not suggest any important differences between the groups.

AUTHORS' CONCLUSIONS

This review provides evidence that sharp-edged IOLs are likely to be associated with less PCO formation than round-edged IOLs, with less Nd:YAG capsulotomy. The effects on visual acuity were less certain. The impact of these lenses on quality of life has not been assessed and there are only very low-certainty comparative data on adverse events.

Posterior Capsule Opacification: A Review of Experimental Studies

Posterior capsule opacification (PCO) is the most common complication of cataract surgery. It causes a gradual deterioration of visual acuity, which would otherwise improve after a successful procedure. Despite recent advances in ophthalmology, this complication has not been eradicated, and the incidence of PCO can be as high as 10%. This article reviews the literature concerning the pathomechanism of PCO and examines the biochemical pathways involved in its formation and methods to prevent this complication. We also review the reported tests performed in cell cultures under laboratory conditions and in experimental animal models and in ex vivo human lens capsules. Finally, we describe research involving human eyes in the clinical setting and pharmacological methods that may reduce the frequency of PCO. Due to the multifactorial etiology of PCO, in vitro studies make it possible to assess the factors contributing to its complications and search for new therapeutic targets. Not all pathways involved in cell proliferation, migration, and contraction of the lens capsule are reproducible in laboratory conditions; moreover, PCO in humans and laboratory animals may be additionally stimulated by various degrees of postoperative reactions depending on the course of surgery. Therefore, further studies are necessary.

Effectiveness and Safety of the Clareon Monofocal Intraocular Lens: Outcomes from a 12-Month Single-Arm Clinical Study in a Large Sample

Purpose

This study assessed effectiveness and safety of the novel Clareon intraocular lens (IOL; model SY60CL; Alcon Vision LLC).

Patients and Methods

This was a prospective, single-arm, unmasked clinical trial at 16 investigative clinical sites in the United States. Included were adults ≥22 years who required cataract extraction by phacoemulsification. Following phacoemulsification, 350 subjects received SY60CL IOL unilaterally; 342 completed the study. Monocular best corrected distance visual acuity (CDVA) and uncorrected distance visual acuity (UDVA) were evaluated. The primary effectiveness endpoint was the percentage of subjects with CDVA ≤0.3 logMAR at month 12. Safety was assessed by monitoring adverse events (AEs). Visual acuity and safety outcomes were compared with historical safety and performance endpoint (SPE) rates.

Results

At 12 months post-implantation, 99.7% of subjects receiving the SY60CL IOL achieved monocular CDVA ≤0.3 logMAR (primary effectiveness endpoint; 1-sided 95% upper confidence limit >SPE rate); 99.7% and 86.8% of subjects achieved monocular CDVA of ≤0.34 (20/40 Snellen or better) and ≤0.04 logMAR (20/20 Snellen or better), respectively. At 12 months, >95% of subjects achieved mean monocular UDVA ≤0.3 logMAR; 97.1% and 57.6% of subjects achieved monocular CDVA of ≤0.34 and ≤0.04 logMAR, respectively. Mean monocular CDVA and UDVA were -0.05 and 0.04 logMAR, respectively. AEs were within SPE limits. The most common nonserious ocular AE was posterior capsule opacification (5.4%). Serious AEs were <1%, and no serious ocular AEs were assessed as related to the device. There were no observations for IOL glistenings at 12 months.

Conclusion

Results of this study supported effectiveness and safety of the SY60CL IOL. Visual acuity outcomes with the SY60CL IOL exceeded the SPE rates for monocular CDVA and AEs were within the limit of historic SPE rates. (Model number SY60WF is the Clareon lens approved by the FDA.).

PHACOVITRECTOMY FOR PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT REPAIR: A Retrospective Review

PURPOSE

To analyze the single surgery success rate and anterior segment complications related to phacoemulsification and intraocular lens implantation in a series of patients undergoing phacovitrectomy for all types of primary rhegmatogenous retinal detachment.

METHODS

We performed a retrospective interventional case series on 302 eyes undergoing phacovitrectomy for primary rhegmatogenous retinal detachment repair between November 1, 2016, and February 2, 2019, in Edmonton, Canada. Primary outcomes included single surgery retinal reattachment rate and anterior segment complications. Secondary outcomes included the effects of proliferative vitreoretinopathy and macula and/or peripheral internal limiting membrane peeling on the rate of surgical success.

RESULTS

The single surgery success rate of phacovitrectomy for all types of primary rhegmatogenous retinal detachment was 85.1%. The presence of proliferative vitreoretinopathy was associated with lower surgical success (odds ratio, 0.33; P = 0.01). Macular internal limiting membrane peeling was associated with higher surgical success (odds ratio, 2.4; P = 0.05). Anterior segment complications included posterior capsular opacification (28.8%), posterior synechiae (10.9%), and posterior capsular rupture (2.3%).

CONCLUSION

Phacovitrectomy is a safe and effective treatment option for the primary repair of rhegmatogenous retinal detachments. This study provides evidence to support the safe incorporation of phacoemulsification and intraocular lens implantation with retinal surgery.

Anti-inflammatory treatment after cataract surgery in Sweden: changes in prescribing patterns from 2010 to 2017

Aims

To investigate changes in the prescribing patterns of postoperative eye drops following cataract surgery in Sweden from 2010 to 2017.

Methods

Data from cataract procedures registered in the National Cataract Register during the month of March from 2010 to 2017 were record linked and sent to the Swedish Prescribed Drug Register, which allowed us to determine which eye drops the patients had obtained from 3 months presurgery to 2 weeks post surgery.

Results

During the 8-year study period, 54 889 surgeries were registered. Combination treatment with steroid and non-steroidal anti-inflammatory drug (NSAID) eye drops increased from 12% in 2010 to 60% in 2017 (p<0.001) while monotherapy with steroids decreased from 71% in 2010 to 26% in 2017 (p<0.001). Monotherapy with NSAIDs after surgery was fairly stable, at 17% in 2010 and 13% in 2017 (p<0.001). Combination treatment was more frequent in patients with diabetic retinopathy (p<0.001) or age-related macular degeneration (p<0.001), while monotherapy with steroids was more frequent in patients with glaucoma (p<0.001). The proportion of monotherapy or combination therapy varied widely between ophthalmic clinics. The prescription of antibiotic eye drops after surgery also varied greatly between clinics, from 0% to 63%, with a national average of 4.9%.

Conclusion

There is a change in the prescription pattern of anti-inflammatory eye drops after cataract surgery in Sweden, with less monotherapy and an increasing proportion of patients receiving a combination of steroid and NSAID eye drops.

The effect of capsule tension ring on posterior capsule opacification: A meta-analysis

Background

Posterior capsule opacification is one of the most common complications after cataract surgery. Studies have suggested that the introduction of a capsule tension ring might play a critical role in the prevention of capsule opacification, yet quantitative evidence is still lacking. This work consists of a meta-analysis on available data in order to explore the influence of a capsule tension ring on posterior capsule opacification.

Methods

A comprehensive review of the literature on capsule tension ring and posterior capsule opacification was carried out using the Embase, Pubmed, Web of Science, and Cochrane electronic databases. The selected studies included randomized controlled trials, retrospective studies and prospective studies published before June 2020. The studies of interest were selected by two reviewers independently from the included studies. Odds ratios (ORs) and standardized mean differences (SMD) were used in order to assess the association. A fixed-effects model or a random-effects model was applied to combine data according to heterogeneities. Sensitivity analysis was used to assess the heterogeneity of the studies. Publication bias was estimated using the Egger test. Statistical analysis was performed using the stata15.1 software.

Results

The meta-analysis included in total 8 studies involving 379 cases and 333 controls. There was a statistically significant difference of Nd:YAG laser capsulotomy rate (OR=0.241, 95% CI: 0.145, 0.400 I²=42.1%) between the capsule tension ring group and the control group, indicating that the tension ring reduced the Nd:YAG laser capsulotomy rate. Further studies with continuous data also revealed that the use of capsule tension ring was associated with a lower posterior capsule opacification score (SMD = -1.402, 95% CI: -2.448, -0.355 I²=95.0%). The sensitivity analysis suggested that the result of the re-combined analysis did not change notably, indicating that the result was reliable and stable. Both pooled analysis showed no evidence of publication bias.

Conclusion

The findings of this meta-analysis confirmed that capsule tension ring might reduce capsule opacification. Further studies should be made to validate the result.

Morphological comparison between three-dimensional structure of immortalized human lens epithelial cells and Soemmering's ring

The incidence rate of post-cataract surgery posterior capsule opacification (PCO) and lens turbidity is about 20% in 5 years. Soemmering's ring, which is a type of PCO also called a regenerated lens with similar tissue structure to that of a human lens, is an important proxy for elucidating the mechanism of lens regeneration and maintenance of transparency. The authors created new human immortalized crystalline lens epithelial cells (iHLEC-NY1s) with excellent differentiation potential, and as a result of culturing the cells by static and rotation-floating methods, succeeded in producing a three-dimensional cell structure model (3D-iHLEC-NY1s) which is similar to Soemmering's ring in tissue structure and expression characteristics of αA-crystalline, βB2-crystalline, vimentin proteins. 3D-iHLEC-NY1s is expected to be a proxy in vitro experimental model of Soemmering's ring to enable evaluation of drug effects on suppression of cell aggregate formation and transparency. By further improving the culture conditions, we aim to control the cell sequence and elucidate the mechanism underlying the maintenance of lens transparency.

Facile multifunctional IOL surface modification via poly(PEGMA-co-GMA) grafting for posterior capsular opacification inhibition

Posterior capsule opacification (PCO) is a significant complication of intraocular lens (IOL) implantation in cataract surgery, in which the adhesion and proliferation of lens epithelial cells (LECs) on the implanted IOL surface play an important role. The surface modification of IOL to prevent LEC adhesion and proliferation is a practical way to reduce the incidence of PCO. In this study, a multifunctional binary copolymer of poly(ethylene glycol) methacrylate (PEGMA) and glycidyl methacrylate (GMA) was synthesized (poly(PEGMA-co-GMA), PPG) and chemically grafted onto the aminolyzed IOL surface, utilizing the coupling reaction of epoxy and amino groups. Doxorubicin (DOX) was subsequently immobilized on the surface coating via the reaction of epoxy and amino groups as well. Taking advantages of the hydrophilicity of the PEG segments in the copolymer coating and the anti-proliferative effects of the DOX, a multifunctional surface coating was easily established by the synthesized copolymer PPG. Such anti-proliferative drug immobilized hydrophilic coating modification may effectively reduce the cell adhesion and proliferation and thus it is hypothesized to have great potential in PCO inhibition. The synthesis of PPG was confirmed by proton nuclear magnetic resonance spectroscopy (¹H-NMR) and Fourier transform infrared spectroscopy (FTIR). The surface coating immobilization was demonstrated by X-ray photoelectron spectroscopy (XPS). The in vitro drug release profiles and the cell behaviors were also investigated to validate the multifunctional coating inhibition effect on cellular adhesion and antiproliferation. Finally, the in vivo ocular implantation was carried out on rabbit eyes to evaluate the effect of the coating modified IOL on the inhibition of postoperative PCO. It followed that such multifunctional coating modification can effectively inhibit the adhesion and proliferation of LECs and significantly reduce the incidence of PCO. All these results reveal that such PPG copolymer modification provides a facile yet effective way to inhibit PCO formation after IOL implantation.

Drug eluting and hydrophilic intraocular lens surface coating was facilely fabricated via poly(PEGMA-co-GMA) grafting. Such a multifunctional coating reduced posterior capsular opacification incidence after implantation effectively.

A Critical Appraisal of New Developments in Intraocular Lens Modifications and Drug Delivery Systems for the Prevention of Cataract Surgery Complications

Cataract surgery is the commonest ophthalmic surgery worldwide. The replacement of the diseased lens with a synthetic one (intraocular lens-IOL) remains the treatment of choice, despite its potential complications that include infection, inflammation and posterior capsule opacification. The potential for drug delivery via the IOL has been researched extensively over a period of twenty-five years, yet there is very limited progress in transferring the findings from research to everyday practice. The objective of this review is to assess the progress made in the field of IOL lens modifications and drug delivery systems over the past five years. Thirty-six studies that were conducted during the past five years were identified and deemed suitable for inclusion. They were grouped in three broad categories, studies that described new methods for loading a drug onto the IOL, assessment of the effects of drugs that were loaded to the IOL and studies that assessed the effects of non-pharmaceutical modifications of IOLs. While considerable progress is continually being made with regard to methods and materials, there is still little capitalization upon these research studies, with no commercially available IOL-based drug delivery system being available. Close cooperation between researchers in basic sciences (chemistry, physics, materials science and pharmacy), clinical researchers, IOL manufacturers and the pharmaceutical industry is an important prerequisite for further development.

The Aravind Pseudoexfoliation Study: 5-Year Postoperative Results. The Effect of Intraocular Lens Choice and Capsular Tension Rings

PURPOSE

We compared rates of intraocular lens (IOL) decentration, neodymium-doped yttrium aluminum garnet capsulotomy for posterior capsule opacification (PCO), and visual acuity (VA) in eyes with and without pseudoexfoliation (PEX) 5 years after undergoing cataract surgery.

DESIGN

Prospective comparative interventional study.

METHODS

This multicenter study population included 1 eye of both 930 cataract patients with and 470 cataract patients without uncomplicated PEX (no small pupils or phacodonesis) all undergoing phacoemulsification by experienced Aravind Eye Care System surgeons. Eyes were randomized to either 1- or 3-piece intraocular lenses (IOLs). PEX eyes were also randomized to either receive or not receive a capsule tension ring. The main outcome measures included IOL decentration and PCO. Secondary outcomes included postoperative best-corrected VA.

RESULTS

Follow-up was 86.2% in the PEX group and 86.7% in the control group at 5 years. The PEX group was older (P < .001) and had more men (P = .01). IOL decentration at 5 years was equally prevalent in PEX and control eyes (1.0% vs 1.1%, respectively, P = .8). Neodymium-doped yttrium aluminum garnet posterior capsulotomy rates for PCO were similar in the PEX group when compared with control subejcts (5.3% compared with 3.2%, respectively, P = .07). Best corrected VA was better at baseline and years 2 and 3 in the control group (P = .0001, P = .0005, and P = .02); however, there was no difference in BCVA at years 1, 4, and 5 between the PEX and control groups (P = .09, P = .29, and P = .5).

CONCLUSION

In a large-scale, long-term, prospective comparative study of cataract surgery in eyes with uncomplicated PEX, the risks of IOL decentration and PCO were low and comparable to that in control subjects. When approaching cataract surgery in eyes with relatively uncomplicated PEX, neither IOL choice (1- vs 3-piece acrylic IOL) nor the presence/absence of a capsule tension ring affects outcomes at 5 years.

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.

CuInS/ZnS quantum dots modified intraocular lens for photothermal therapy of posterior capsule opacification

Posterior capsule opacification (PCO) after cataract surgery is one of the leading causes of visual impairment and blindness. The cause of PCO is the capsule fibrosis developed on implanted Intraocular Lens (IOLs) by the de-differentiation of Lens Epithelial Cells (LECs) undergoing epithelial mesenchymal transition. How to prevent PCO has been a challenge to scientists and ophthalmologists for decades. Here we demonstrated the use of carboxylated CuInS/ZnS quantum dots (ZCIS QDs), which are free of toxic heavy metals and are more biocompatible, as photothermal nanomedicines. The ZCIS QDs are modified onto the non-optical section of IOLs by a facial activation-immersion method. Under mild NIR laser irradiation, ZCIS QDs modified IOLs (QDs-IOLs) will generate localized heat and prevent the proliferation of LECs onto the surface of QDs-IOLs. Our findings provide experimental evidence for further application of combined nanotechnology and photothermal therapy for the clinical treatment of PCO.

Vision function of pseudophakic eyes with posterior capsular opacification under different speed and spatial frequency

PURPOSE

To investigate the characteristics of dynamic visual acuity (DVA) and contrast sensitivity (CS) in pseudophakic patients with posterior capsular opacification (PCO).

METHODS

Fifty-four eyes (36 patients) with PCO planned for laser capsulotomy were recruited. They underwent examinations of static visual acuity (SVA), DVA, CS and optical quality analysis (OQAS) before and one week after the laser treatment. Improvements in each index after laser treatment were analyzed. The visual quality of patients with good initial vision was studied separately.

RESULTS

SVA, DVA and CS all significantly increased after capsulotomy (P < 0.05). Postoperative improvements in DVA were higher than in SVA, but they decreased when the speed increased. DVA at 15 dps gained the most improvement after capsulotomy. DVA at all analyzed speeds was significantly lower than SVA (P = 0.000). There was a significant speed-dependent decrease in DVA at lower speeds compared with higher speeds. The postoperative improvements in CS decreased when the spatial frequency was increased. The CS at the lower frequencies of 3 cpd and 6 cpd was the most improved after capsulotomy. CS was much lower at high frequencies (p < 0.05). There was a significant decrease in CS at higher spatial frequencies compared with lower frequencies. DVA improvements were correlated with CS improvements at medium spatial frequencies and with objective scattering index and Strehl ratio. The CS at all frequencies significantly improved for patients with good initial vision.

CONCLUSION

PCO could impair dynamic vision function, but CS was a more sensitive indication of visual complaints in patients with slight PCO.

Posterior Capsule Opacification With Two Hydrophobic Acrylic Intraocular Lenses: 3-Year Results of a Randomized Trial

PURPOSE

To compare the incidence and intensity of posterior capsule opacification (PCO) and neodymium-yttrium-aluminum-garnet (Nd:YAG) capsulotomy rates between 2 similar open-loop single-piece hydrophobic acrylic intraocular lenses (IOLs) that differ in the proprietary material characteristics and design features, over a period of 3 years.

DESIGN

Randomized, prospective, patient- and examiner-masked clinical trial with intraindividual comparison.

METHODS

Setting: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.

PATIENT POPULATION

Eighty patients (160 eyes) had bilateral cataract surgery and received a Vivinex XY1 IOL in 1 eye and an AcrySof SN60WF IOL in the other eye.

OBSERVATION PROCEDURES

Follow-up examinations were performed 3 years after surgery. Digital retroillumination images were taken of each eye. The amount of PCO (score: 0-10) was assessed subjectively at the slit lamp and objectively using automated image analysis software (AQUA).

MAIN OUTCOME MEASURE

PCO score (scale, 0-10).

RESULTS

The mean objective PCO score of the Vivinex XY1 IOLs was 0.9 ± 0.8 compared to the PCO score of 1.4 ± 1.1 for the AcrySof SN60WF IOLs (P < .001). Three years postoperatively, 11.4% of patients had an Nd:YAG capsulotomy in the Vivinex XY1 eye and 18.6% had a capsulotomy in the AcrySof SN60WF eye (P = .23).

CONCLUSION

The new hydrophobic acrylic Vivinex XY1 IOL showed significantly lower PCO rates and lower YAG rates compared to the AcrySof SN60WF IOL. The interaction of various factors such as hydrophobic material, smooth optic surface, and sharp posterior optic edge plays a key role in PCO development.

Imaging of Age-Related Macular Degeneration by Adaptive Optics Scanning Laser Ophthalmoscopy in Eyes With Aged Lenses or Intraocular Lenses

Purpose

To assess the performance of adaptive optics scanning laser ophthalmoscopy (AOSLO) in a large sample of eyes with or without age-related macular degeneration (AMD) and with cataracts or intraocular lenses (IOLs).

Methods

Patients with various degrees of AMD and age-similar normal subjects underwent fundus photography. Cataract severity and IOL clarity were assessed by fundus reflex photographs. In phakic eyes, lenticular opacity was graded as nuclear, cortical, or posterior subcapsular cataract. In eyes with IOLs, lens clarity was assessed by posterior capsule opacification (PCO). Quality of AOSLO images of the macular photoreceptor mosaic was classified as good, adequate or inadequate by human graders in a subjective assessment of cone visibility.

Results

A total of 159 eyes in 80 subjects (41 males, 39 females, aged 72.5 ± 11.5 years, 16 normals) were examined. Seventy-nine eyes had IOLs, and 80 eyes were phakic. AOSLO produced good images in 91 eyes (57%), adequate images in eight eyes (5%), and inadequate images in 27 eyes (17%). AOSLO did not acquire images in 33 eyes (21%), because of dense lenticular opacity, widespread PCO, or problems specific to individual subjects.

Conclusions

AOSLO images considered at least Adequate or better for visualizing cone photoreceptors were acquired from 62% of study eyes.

Translational Relevance

AOSLO can be used as an additional imaging modality to investigate the structure of cone photoreceptors in research on visual function in AMD and in clinical trials involving older patients.

Histopathological changes in the anterior segment with anterior and posterior chamber intraocular lens

OBJECTIVE

Patients have shown a lowering of intraocular pressure (IOP) after cataract surgery. Histopathology studies have reported trabecular meshwork (TM) changes in pseudophakic eyes with posterior chamber intraocular lens (PCIOL) and have eluded to the mechanisms for IOP decrease. Unlike PCIOLs, TM histopathology changes after implantation of an anterior chamber intraocular lens (ACIOL) have not been studied, to our knowledge. Therefore, this study aims to examine the histopathological changes in both the TM and corneal endothelium among donor eyes with ACIOL, PCIOL, and phakic eyes.

METHODS

Forty fixed postmortem donor eyes were obtained, sectioned, and embedded. Slides were stained with Masson's trichrome and CD31 vascular endothelial antibody, and further digitalized. Customized Medical Parachute TMAN software quantified the cellular components, the trabecular extracellular matrix (ECM), ECM fibrosis, and trabecular area. Schlemm's canal and corneal endothelium were quantified across the ACIOL, PCIOL, and phakic groups.

RESULTS

Cellular area component of the TM was lower in the ACIOLs and PCIOLs than in phakic eyes, but statistically significant only between PCIOL and phakic eyes (p = 0.0023). ECM area component, TM fibrosis score and TM lamellae area, ciliary process fibrosis, and CD31 expression in Schlemm's canal showed no differences (p = 0.40, 0.99, 0.10, 0.83, 0.45). Significantly lower corneal endothelial cells were seen in ACIOLs compared with both PCIOLs and phakic eyes (p = 0.0002).

CONCLUSIONS

ACIOLs and PCIOLs in our sample group showed that there is loss of cellular components in the TM compared with the phakic eyes, with PCIOLs displaying the least amount of TM cells statistically, in this cohort. The ACIOLs led to a greater loss of corneal endothelial cells than both PCIOLs and phakic eyes after cataract surgery. The endothelial cells in Schlemm's canal did not seem to be affected by the IOL placements. Therefore, this study illustrates that there are histopathological differences seen with the placements of ACIOLs in both TM and cornea.

Efficacy of long-term topical flurbiprofen in limiting lens capsule opacities following phacoemulsification in dogs

OBJECTIVE

To assess lens capsule opacity (LCO) following phacoemulsification in dogs receiving long-term topical ophthalmic flurbiprofen sodium 0.03%.

ANIMAL STUDIED

Twenty-five client owned dogs undergoing phacoemulsification surgery for either diabetic or nondiabetic cataracts.

METHODS

Prospective, randomized, masked clinical study assessing two groups of dogs for twelve months following phacoemulsification. All dogs underwent a complete eye examination and were photographed at each visit, beginning three weeks post-surgery, and repeated at 2, 3, 6, and 12 months post-surgery. Post-operative treatment protocols were similar for both groups, except that Group F received topical flurbiprofen once daily for 12 months and Group A received artificial tears once daily for 12 months. Digital photographs were analyzed for LCO using a subjective grading scale (0-4). The change in capsular opacities from 3 weeks to 12 months post-surgery was evaluated for each dog, and the groups were compared.

RESULTS

There were 25 dogs evaluated post-phacoemulsification at each designated time point of the study. There were 12 dogs in Group A and 13 dogs in Group F. There was no significant statistical difference in LCO score between Groups A and F at baseline (3 weeks post-surgery), 6 months post-surgery, or 12 months post-surgery. Scores did not change significantly from baseline to 12 months within or between groups.

CONCLUSIONS

Topical ophthalmic flurbiprofen sodium 0.03% solution applied once daily for 12 months following phacoemulsification does not appear to lead to a decrease in LCO formation as compared to artificial tears control.

The Effect of Capsulotomy Shape on Intraocular Light-Scattering after Nd:YAG Laser Capsulotomy

Purpose

To investigate the effects of capsulotomy shape on the visual acuity and visual quality after neodymium: yttrium aluminum garnet laser capsulotomy.

Methods

In this study, a total of 42 eyes from 35 patients with posterior capsule opacification were divided into the circular and cruciate groups. The corrected distance visual acuity (CDVA), objective scatter index (OSI), modulation transfer function cutoff (MTF cutoff), Strehl ratio, and Optical Quality Analysis System values at contrasts of 100%, 20%, and 9% (OV-100, OV-20, and OV-9) were measured at precapsulotomy and 1 week and 1 month postcapsulotomy. The pseudophakic dysphotopsia questionnaire (PDQ) was used to evaluate the subjects' satisfaction with treatment.

Results

OSI values were significantly higher in the cruciate group than in the circular group at 1 week and 1 month after capsulotomy (P=0.013 and P < 0.001). No significant difference was found in the OSI values between the two groups before capsulotomy (t = 0.52; P=0.61). The decrease in OSI was higher in the circular group than in the cruciate group at 1 week and 1 month after capsulotomy (P=0.036 and P=0.019). No significant differences were found in the Strehl ratio, MTF cutoff, CDVA, OV-100, OV-20, and OV-9 between the two groups at 1 week and 1 month after capsulotomy (P > 0.05). The PDQ results showed that patients with circular-shaped capsulotomy complained less with intolerance of bright lights than those with cruciate-shaped capsulotomy.

Conclusions

Circular-shaped capsulotomy can induce less intraocular light scattering and increase patient satisfaction.

Topical steroid alone vs a combination with a posterior segment NSAID after Nd-YAG capsulotomy: Is the posterior segment NSAID really necessary?

Purpose:

To compare the effect of topical 1% prednisolone acetate and 0.09% bromfenac versus topical 1% prednisolone acetate alone on macular thickness following Nd: YAG laser capsulotomy.

Materials and Methods:

About 150 eyes with posterior capsule opacification following were included. All patients were treated with Nd: YAG laser posterior capsulotomy. Patients were randomly divided into two groups of 75. Group 1-Patients received: Topical 1% prednisolone acetate and Topical 0.09% bromfenac. Group 2-Patients received: Topical 1% prednisolone acetate alone. Outcome measures by an independent observer were BCVA by Snellen chart, IOP by NCT, and Central Macular Thickness (CMT) by Macular OCT. All patients were examined before the procedure, 1 h after the procedure, at 1 week, and at 6 weeks.

Statistics:

1. Quantitative variables: Mann-Whitney Test and Wilcoxon ranked sum test. 2. Qualitative variables: Chi-square test. A P value of < 0.05 was considered statistically significant.

Results:

Mean IOP increase in both groups is statistically significant at 1 h and later decreases back to nonsignificant levels at 1 week and 6 weeks. No significant change in mean CMT was seen in the duration of 6 weeks neither in Group 1 nor Group 2.

Conclusion:

Prophylactic antiglaucoma medications are not recommended in patients undergoing Nd: YAG laser capsulotomy. No evidence of cystoid macular edema was recorded till the end of 6 weeks follow-up.

Endoplasmic reticulum stress regulates epithelial‑mesenchymal transition in human lens epithelial cells

Epithelial‑to‑mesenchymal transition (EMT) of human lens epithelial cells (HLECs) serve an important role in cataract formation. The endoplasmic reticulum stress response (ER stress) has been demonstrated to regulate EMT in a number of tissues. The aim of the present study was to demonstrate the role of ER stress on EMT in HLECs. HLECs were treated with tunicamycin (TM) or thapsigargin (TG) to disturb ER homeostasis, and 4‑phenylbutyric acid (PBA) or sodium tauroursodeoxycholate (TUDCA) to restore ER homeostasis. Cell morphology was evaluated after 24 h. The long axis and aspect ratio of the cells were analyzed using ImageJ software. The results demonstrated that HLECs adopted an elongated morphology following treatment with TG, and the cellular aspect ratio increased. However, this morphological change was not observed following combination treatment with TG and PBA. Western blot analysis and immunofluorescence staining were used to measure the protein expression levels. A wound‑healing assay was performed to evaluate cell migration. Treatment with TM or TG increased the expression of the ER stress markers glucose‑regulated protein 78, phosphorylated eukaryotic initiation factor 2α, activating transcription factor (ATF)6, ATF4 and inositol‑requiring protein 1α and the EMT markers fibronectin, vimentin, α‑smooth muscle actin and neural cadherin. Furthermore, treatment with TM or TG decreased the expression of the epithelial cell marker epithelial cadherin and enhanced cell migration, which effects were inhibited following treatment with PBA or TUDCA. These results indicates that enhanced ER stress induced EMT and subsequently increased cell migration in HLECs in vitro.

Identification and Description of Reliable Evidence for 2016 American Academy of Ophthalmology Preferred Practice Pattern Guidelines for Cataract in the Adult Eye

Importance

Trustworthy clinical practice guidelines require reliable systematic reviews of the evidence to support recommendations. Since 2016, the American Academy of Ophthalmology (AAO) has partnered with Cochrane Eyes and Vision US Satellite to update their guidelines, the Preferred Practice Patterns (PPP).

Objective

To describe experiences and findings related to identifying reliable systematic reviews that support topics likely to be addressed in the 2016 update of the 2011 AAO PPP guidelines on cataract in the adult eye.

Design, Setting, and Participants

Cross-sectional study. Systematic reviews on the management of cataract were searched for in an established database. Each relevant systematic review was mapped to 1 or more of the 24 management categories listed under the Management section of the table of contents of the 2011 AAO PPP guidelines. Data were extracted to determine the reliability of each systematic review using prespecified criteria, and the reliable systematic reviews were examined to find whether they were referenced in the 2016 AAO PPP guidelines. For comparison, we assessed whether the reliable systematic reviews published before February 2010 the last search date of the 2011 AAO PPP guidelines were referenced in the 2011 AAO PPP guidelines. Cochrane Eyes and Vision US Satellite did not provide systematic reviews to the AAO during the development of the 2011 AAO PPP guidelines.

Main Outcomes and Measures

Systematic review reliability was defined by reporting eligibility criteria, performing a comprehensive literature search, assessing methodologic quality of included studies, using appropriate methods for meta-analysis, and basing conclusions on review findings.

Results

From 99 systematic reviews on management of cataract, 46 (46%) were classified as reliable. No evidence that a comprehensive search had been conducted was the most common reason a review was classified as unreliable. All 46 reliable systematic reviews were cited in the 2016 AAO PPP guidelines, and 8 of 15 available reliable reviews (53%) were cited in the 2011 PPP guidelines.

Conclusions and Relevance

The partnership between Cochrane Eyes and Vision US Satellite and the AAO provides the AAO access to an evidence base of relevant and reliable systematic reviews, thereby supporting robust and efficient clinical practice guidelines development to improve the quality of eye care.

Effect of Nd:YAG laser posterior capsulotomy on intraocular pressure, refraction, anterior chamber depth, and macular thickness

Purpose: To see the effect of Nd:YAG laser capsulotomy on intraocular pressure (IOP), refraction, best-corrected visual acuity (BCVA), anterior chamber depth (ACD), and macular thickness.

Methodology: The authors conducted a prospective, descriptive study on pseudophakic eyes with posterior capsule opacification who underwent Nd:YAG laser capsulotomy. BCVA, IOP, spherical equivalent (SE), macular thickness, and ACD were noted preoperatively, at 1 hr postoperatively and at 1-month follow-up. Patients were divided into two groups based on energy used (Group I ≤50 mJ, Group II >50 mJ). None of the patients received prophylactic antiglaucoma medications either before or after the procedure.

Results: There were 96 eyes of 83 patients. Mean total energy levels were 26.64±12.92 mJ in Group I and 81.96±32.10 mJ in Group II. BCVA at 1 hr and 1 month postoperatively improved significantly in both the groups compared to preoperative BCVA (P<0.001). There was no significant change in SE compared to preoperative values in both the groups. The ACD continued to increase significantly in both the groups at both 1 hr and 1-month follow-up. In Group I, IOP increased at 1 hr postoperatively (P=0.023) and declined to preoperative levels at 1 month. In Group II, IOP increased at 1 hr postoperatively (P<0.001) and did not return to preoperative levels at 1-month follow-up (P=0.003). Likewise, macular thickness increased at 1 hr in both groups (P<0.001). In Group I, macular thickness decreased significantly to preoperative level at 1 month whereas in Group II, it remained significantly high at 1-month follow-up (P=0.006). There was no case with serious rise in IOP or cystoid macular edema.

Conclusion: Statistically significant increment in IOP and macular thickness occurs after Nd:YAG laser capsulotomy which however may not necessitate the use of any medications.