The Protective Effect of Metformin Use on Early Nd:YAG Laser Capsulotomy

Association Between Intraoperative Cataract Surgical Complications and Mortality

PURPOSE

To evaluate the association between intraoperative complications of cataract surgery and postoperative mortality.

METHODS

A retrospective review of patients who underwent cataract surgery at our institution from 2014 to 2020 was conducted. Intraoperative complications included choroidal hemorrhage, posterior capsule rupture, vitreous loss, retained lens, and/or severe zonular dialysis in either eye. All-cause mortality statistics were obtained through a collaborative agreement with the Colorado Department of Public Health and Environment. Hazard ratios (HRs) from Cox proportional hazard models were used to estimate survival following cataract surgery.

RESULTS

Among 8,054 patients, the mean follow-up time was 4.4 (SD = 2.3) years and the mortality rate was 15% (n = 1,175). The overall complication rate was 2.2% (n = 181), and the rate of retained lens was 0.7% (n = 58). In univariate analysis, retained lens (HR: 1.86, 95% CI: 1.08-3.21, p = 0.026), severe zonular dialysis (HR: 2.00, 95% CI: 1.29-3.12, p = 0.002), and any intraoperative complication (HR: 1.51, 95% CI: 1.09-2.11, p = 0.015) were associated with higher hazard of mortality. When adjusted for demographic factors, comorbid medical conditions, and pre-operative visual acuity, intraoperative complications were not associated with mortality.

CONCLUSION

Intraoperative cataract surgery complications were associated with mortality in univariate analysis. However, this association was not significant in the multivariable analysis as it is confounded by other factors such as pre-operative visual acuity.

GDF-15 Attenuates the Epithelium-Mesenchymal Transition and Alleviates TGFβ2-Induced Lens Opacity

Purpose

We sought to evaluate the efficacy of growth differentiation factor (GDF)-15 treatment for suppressing epithelial-mesenchymal transition (EMT) and alleviating transforming growth factor β2 (TGFβ2)-induced lens opacity.

Methods

To test whether GDF-15 is a molecule that prevents EMT, we pretreated the culture with GDF-15 in neural progenitor cells, retinal pigment epithelial cells, and lens epithelial cells and then treated with factors that promote EMT, GDF-11, and TGFβ2, respectively. To further investigate the efficacy of GDF-15 on alleviating lens opacity, we used mouse lens explant culture to mimic secondary cataracts. We pretreated the lens culture with GDF-15 and then added TGFβ2 to develop lens opacity (n = 3 for each group). Western blot and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used to measure EMT protein and gene expression, respectively.

Results

In cell culture, GDF-15 pretreatment significantly attenuated EMT marker expression in cultured cells induced by treatment with GDF-11 or TGFβ2. In the lens explant culture, GDF-15 pretreatment also reduced mouse lens opacity induced by exposure to TGFβ2.

Conclusions

Our results indicate that GDF-15 could alleviate TGFβ2-induced EMT and is a potential therapeutic agent to slow or prevent posterior capsular opacification (PCO) progression after cataract surgery.

Translational Relevance

Cataracts are the leading cause of blindness worldwide, with the only current treatment involving surgical removal of the lens and replacement with an artificial lens. However, PCO, also known as secondary cataract, is a common complication after cataract surgery. The development of an adjuvant that slows the progression of PCO will be beneficial to the field of anterior complications.

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.

Recent progress and research trend of anti-cataract pharmacology therapy: A bibliometric analysis and literature review

Cataract is the leading cause of blindness worldwide. Cataract phacoemulsification combined with intraocular lens implantation causes great burden to global healthcare, especially for low- and middle-income countries. Such burden would be significantly relieved if cataracts can effectively be treated or delayed by non-surgical means. Excitingly, novel drugs have been developed to treat cataracts in recent decades. For example, oxysterols are found to be able to innovatively reverse lens clouding, novel nanotechnology-loaded drugs improve anti-cataract pharmacological effect, and traditional Chinese medicine demonstrates promising therapeutic effects against cataracts. In the present review, we performed bibliometric analysis to provide an overview perspective regarding the research status, hot topics, and academic trends in the field of anti-cataract pharmacology therapy. We further reviewed the curative effects and molecular mechanisms of anti-cataract drugs such as lanosterol, metformin, resveratrol and curcumin, and prospected the possibility of their clinical application in future.

Long Non-Coding RNA H19 Prevents Lens Fibrosis through Maintaining Lens Epithelial Cell Phenotypes

The integrity of lens epithelial cells (LECs) lays the foundation for lens function and transparency. By contrast, epithelial-mesenchymal transition (EMT) of LECs leads to lens fibrosis, such as anterior subcapsular cataracts (ASC) and fibrotic forms of posterior capsule opacification (PCO). However, the underlying mechanisms remain unclear. Here, we aimed to explore the role of long non-coding RNA (lncRNA) H19 in regulating TGF-β2-induced EMT during lens fibrosis, revealing a novel lncRNA-based regulatory mechanism. In this work, we identified that lncRNA H19 was highly expressed in LECs, but downregulated by exposure to TGF-β2. In both human lens epithelial explants and SRA01/04 cells, knockdown of H19 aggravated TGF-β2-induced EMT, while overexpressing H19 partially reversed EMT and restored lens epithelial phenotypes. Semi-in vivo whole lens culture and H19 knockout mice demonstrated the indispensable role of H19 in sustaining lens clarity through maintaining LEC features. Bioinformatic analyses further implied a potential H19-centered regulatory mechanism via Smad-dependent pathways, confirmed by in vitro experiments. In conclusion, we uncovered a novel role of H19 in inhibiting TGF-β2-induced EMT of the lens by suppressing Smad-dependent signaling, providing potential therapeutic targets for treating lens fibrosis.

Refraction Shift After Nd:YAG Posterior Capsulotomy in Pseudophakic Eyes: A Systematic Review and Meta-analysis

PURPOSE

To explore ocular refraction shift after Neodymium: yttrium aluminum garnet (Nd:YAG) posterior capsulotomy in pseudophakic eyes.

METHODS

A systematic literature search was performed in the PubMed, Embase, and Cochrane Library databases until November 10, 2021. Studies on the evaluation of changes in spherical equivalent (SE), cylindrical error (CE), or anterior chamber depth (ACD) after Nd:YAG laser capsulotomy were included in the meta-analysis. The review was registered in the international platform of registered systematic review and meta-analysis protocols (INPLASY202120059).

RESULTS

A total of 805 eyes from 18 studies were included in the final analysis. The pooled mean differences in SE from baseline to postoperative follow-up points were not significant (1 hour: 0.04 diopters [D], 95% CI: -0.13 to 0.21, P = .644; 1 week: 0.04 D, 95% CI: -0.12 to 0.20, P = .640; 1 month: 0.05 D, 95% CI: -0.06 to 0.16, P = .349). There was no significant difference between baseline CE and any subsequent visit (1 week: 0.14 D, 95% CI: -0.06 to 0.33, P = .172; 1 month: 0.17 D, 95% CI: -0.04 to 0.38, P = .108). No statistical difference in ACD from baseline was observed either (1 hour: 0.01 mm, 95% CI: -0.07 to 0.09, P = .846; 1 week: -0.12 mm, 95% CI: -0.24 to 0.01, P = .079; 1 month: -0.06, 95% CI: -0.14 to 0.01, P = .110).

CONCLUSIONS

Neither ocular refraction nor ACD changed within 1 month after laser capsulotomy, suggesting laser capsulotomy did not affect ocular refraction in short-term observation. [J Refract Surg. 2022;38(7):465-473.].

Role of the AMPK signalling pathway in the aetiopathogenesis of ocular diseases

BACKGROUND

AMP-activated protein kinase (AMPK) plays a precise role as a master regulator of cellular energy homeostasis. AMPK is activated in response to the signalling cues that exhaust cellular ATP levels such as hypoxia, ischaemia, glucose depletion and heat shock. As a central regulator of both lipid and glucose metabolism, AMPK is considered to be a potential therapeutic target for the treatment of various diseases, including eye disorders.

OBJECTIVE

To review all the shreds of evidence concerning the role of the AMPK signalling pathway in the pathogenesis of ocular diseases.

METHOD

Scientific data search and review of available information evaluating the influence of AMPK signalling on ocular diseases.

RESULTS

Review highlights the significance of AMPK signalling in the aetiopathogenesis of ocular diseases, including cataract, glaucoma, diabetic retinopathy, retinoblastoma, age-related macular degeneration, corneal diseases, etc. The review also provides the information on the AMPK-associated pathways with reference to ocular disease, which includes mitochondrial biogenesis, autophagy and regulation of inflammatory response.

CONCLUSION

The study concludes the role of AMPK in ocular diseases. There is growing interest in the therapeutic utilization of the AMPK pathway for ocular disease treatment. Furthermore, inhibition of AMPK signalling might represent more pertinent strategy than AMPK activation for ocular disease treatment. Such information will guide the development of more effective AMPK modulators for ocular diseases.[Formula: see text].