Impact of anterior capsular polishing on capsule opacification rate in eyes undergoing femtosecond laser-assisted cataract surgery

YAG Capsulotomy Rates in Patients Following Cataract Surgery and Implantation of New Hydrophobic Preloaded Intraocular Lens in an Australian Cohort: 3-Year Results

Purpose

To assess the risk of posterior capsular opacification (PCO) following implantation of the Clareon lens.

Materials and Methods

Retrospective analysis was performed for 484 consecutive eyes that had undergone phacoemulsification and implantation of a monofocal lens (CNA0T) between April 2018 and February 2020. Eyes with other ocular pathology that may affect outcomes, previous refractive surgery or eyes corrected for a near target were excluded. Incidence of PCO and YAG capsulotomy was recorded and regression analysis was performed to determine risk factors associated with PCO formation.

Results

Overall incidence of PCO following implantation of the CNA0T monofocal lens was 3.7% (18 eyes) at 1 year with 1.9% (9 eyes) undergoing YAG capsulotomy. At 3 years, 8.7% (42 eyes) had developed PCO and 4.1% (20 eyes) had undergone YAG capsulotomy cumulatively. Primary open angle glaucoma (POAG; OR = 6.53; 95% CI = 18.68, 2.28; P = 0.0005), age-related macular degeneration (AMD; OR = 2.35; 95% CI = 5.21, 1.06; P = 0.036), vitreomacular traction (VMT; OR = 7.32; 95% CI = 45.08, 1.19; P = 0.032), retinal vein occlusion (RVO; OR = 8.42; 95% CI = 38.99, 1.82; P = 0.006) and history of anti-VEGF therapy (OR = 3.22; 95% CI = 10.26, 1.01; P = 0.048) were positively associated with an increased risk of PCO.

Conclusions

Incidence of PCO requiring YAG capsulotomy was relatively low. However, certain co-morbidities were found to increase the risk of PCO development, most significantly POAG and RVO.

Arginase-1 promotes lens epithelial-to-mesenchymal transition in different models of anterior subcapsular cataract

BACKGROUND

Arginase-1 (ARG1) promotes collagen synthesis and cell proliferation. ARG1 is highly expressed in various tumour cells. The mechanisms of ARG1 in epithelial-to-mesenchymal transition (EMT)-associated cataracts were studied herein.

METHODS

C57BL/6 mice, a human lens epithelial cell line (HLEC-SRA01/04), and human lens capsule samples were used in this study. The right lens anterior capsule of the mouse eye was punctured through the central cornea with a 26-gauge hypodermic needle. Human lens epithelial cells (HLECs) were transfected with ARG1-targeted (siARG1) or negative control siRNA (siNC). For gene overexpression, HLECs were transfected with a plasmid bearing the ARG1 coding sequence or an empty vector. Medium containing 0.2% serum with or without transforming growth factor beta-2 (TGF-β2) was added for 6 or 24 h to detect mRNA or protein, respectively. The expression of related genes was measured by quantitative real-time polymerase chain reaction (RT-qPCR), western blotting, and immunohistochemical staining. Transwell assays and wound healing assays were used to determine cell migration. Cell proliferation, superoxide levels, nitric oxide (NO) levels, and arginase activity were estimated using Cell Counting Kit-8 assays, a superoxide assay kit, an NO assay kit, and an arginase activity kit.

RESULTS

ARG1, alpha-smooth muscle actin (α-SMA), fibronectin, and Ki67 expression increased after lens capsular injury, while zonula occludens-1 (ZO-1) expression decreased. Fibronectin and collagen type I alpha1 chain (collagen 1A1) expression increased, and cell migration increased significantly in ARG1-overexpressing HLECs compared with those transfected with an empty vector after TGF-β2 treatment. These effects were reversed by ARG1 knockdown. The arginase-related pathway plays an important role in EMT. mRNAs of enzymes of the arginase-related pathway were highly expressed after ARG1 overexpression. ARG1 knockdown suppressed these expression changes. Numidargistat (CB-1158) dihydrochloride (CB-1158), an ARG1 inhibitor, suppressed TGF-β2-induced anterior subcapsular cataract (ASC) by reducing the proliferation of lens epithelial cells (LECs) and decreasing fibronectin, α-SMA, collagen 1A1, and vimentin expression. Compared with that in nonanterior subcapsular cataract (non-ASC) patients, the expression of ARG1, collagen 1A1, vimentin, fibronectin, and Ki67 was markedly increased in ASC patients.

CONCLUSIONS

ARG1 can regulate EMT in EMT-associated cataracts. Based on the pathogenesis of ASC, these findings are expected to provide new therapeutic strategies for patients.

Lens Epithelial Cell Removal in Routine Phacoemulsification: Is It Worth the Bother?

PURPOSE

To review the literature on crystalline lens epithelial cell (LEC) removal in routine phacoemulsification and determine whether it should be incorporated as part of a surgeon's standard technique.

DESIGN

Perspective.

METHODS

Expert commentary with video demonstrations on techniques of removal of LECs and associated potential complications. Discussion incorporates the importance of LEC removal, a review of techniques to prevent posterior capsular opacification (PCO), and the effects of intraocular lens design on LEC proliferation and PCO.

RESULTS

The evidence suggests that LEC removal should be routinely performed as it can be carried out safely and with considerable short- and long-term benefits for patients. With effective cleanup, there is reduced anterior capsule opacification, fibrosis, and decentration of the capsular bag as well as reduced rates of posterior capsular opacification. Techniques for removal are easy to learn, with very low complication rates, and can reduce the risk of the long-term need for technically complex procedures such as intraocular lens explantation.

CONCLUSIONS

LEC removal from both the anterior and posterior capsule is part of a continuous, incremental improvement of cataract surgery and should be introduced to ophthalmology trainees during their formative years as part of their regular cataract surgery armamentarium.

Comparison of Anterior Capsule Polishing on the Rate of Neodymium: YAG Laser Capsulotomy After Two Multifocal Intraocular Lens Implantation

Purpose

To compare the impact of anterior capsule polishing (ACP) during cataract surgery on the rate of neodymium: YAG (Nd: YAG) laser capsulotomy in pseudophakic eyes with two multifocal intraocular lenses (MIOLs).

Methods

Data were collected on patients who underwent cataract surgery and implanted segmental refractive MIOLs (SBL-3, Lenstec) or diffracted MIOLs (AT LISA tri 839MP, Carl Zeiss Meditec). The participants were divided into ACP and non-ACP groups based on whether the anterior capsule was polished. The primary outcome measure was whether Nd: YAG capsulotomy was performed during the 3 years follow-up. We used Kaplan–Meier survival curves to determine the time from IOL implantation to Nd: YAG laser capsulotomy.

Results

ACP and non-ACP groups comprised 70 and 60 eyes, respectively. One year postoperatively, 7.14% of ACP group eyes and 8.33% of non-ACP group required Nd: YAG laser capsulotomy (P > 0.99). After 2 years, it was 24.29 and 18.33%, respectively (P = 0.52), while after 3 years, it reached 30.0 and 28.33% (P = 0.85). No distinct difference existed in the probability of using Nd: YAG laser in both groups evaluated using Kaplan-Meier survival curves (P = 0.81). Patients with diffractive MIOLs (AT LISA tri 839MP) implantation were more likely to require Nd: YAG laser capsulotomy (P < 0.01).

Conclusion

Polishing the anterior capsule had no remarkable effect on reducing the rate of Nd: YAG laser capsulotomy following phacoemulsification in MIOLs. Patients with diffractive MIOLs implantation had a high probability of requiring Nd: YAG laser capsulotomy.