Age-related Cataract Research Articles

A Comparison of Functional Endothelial Changes between Phacoemulsification with PCIOL and Manual Small Incision Cataract Surgery with PCIOL

Intraocular surgery e.g., cataract surgery with PCIOL implantation is one of the leading causes of corneal endothelial injury and change in the functionality of the cornea. This observational study was conducted in the Department of Ophthalmology of Combined Military Hospital (CMH), Dhaka Cantonment, Dhaka, Bangladesh, between January and July of 2016, to assess and compare functional changes in cornea (i.e., endothelial thickness) after phacoemulsification with posterior chamber intraocular lens (PCIOL) implantation and manual small incision cataract surgery (MSICS) with PCIOL implantation. A total of 80 patients of age-related cataract were randomly selected based on inclusion and exclusion criteria. All patients underwent complete ophthalmic evaluation pre- and post-operatively (at day 1, after 1 week and 3 months) specifically for observation of the endothelial changes in cornea. Specular microscopy was done to assess corneal endothelial change. The mean central corneal thickness was increased at day 1 (564.71±22.45μ vs. 555.10±40.57μ), after 1 week (539.43±22.16μ vs. 535.08±38.87μ) and 3 months (523.49±21.29μ vs. 520.05±33.68μ) after phacoemulsification and MSICS from their preoperative value (508.72±23.96μ vs. 503.62±32.06μ) respectively. However, the differences were not statistically significant between two groups (P>0.05). The mean percentage of central corneal thickness change at day1, after 1 week and after 3 months following cataract surgery were found 11.01±6.30% and 10.22±26.54% at day 1, 6.04±7.52% and 6.25±21.24% after 1 week, 2.90±11.14% and 3.26±5.05% after 3 months in phacoemulsification and MSICS cases respectively. However, no statistically significant difference was observed in percentage of central corneal thickness change of both groups (P>0.05). To summarize, an increased central corneal thickness was observed after phacoemulsification and SICS from their preoperative values. Mugda Med Coll J. 2024; 7(1): 14-18

Circular RNA Circ_0122396 Regulates Human Lens Epithelial Cell Progression by Regulating miR-23a-3p and MMP16 in Age-Related Cataract

Background CircRNA plays a regulatory role in multiple life processes. Circ_0122396 could participate in the regulation of age-related cataract (ARC) progression. However, the precise molecular mechanisms of circ_0122396 In ARC remain enigmatic. Methods Circ_0122396, microRNA (miR)-23a-3p, and matrix metalloprotease (MMP)-16 (MMP16) expression levels were detected via quantitative real-time polymerase chain reaction. Western blot was used to detect the levels of MMP16 and apoptosis-related proteins. Cell counting kit-8 analysis and 5-ethynyl-2’-deoxyuridine assay were used to assess human lens epithelial cells (HLECs) proliferation. Flow cytometry was performed to determine cell apoptosis. Levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-PX) were measured using commercial kits. Luciferase reporter assay, RNA immunoprecipitation (RIP) assay, and RNA pull-down assay were used to examine the interaction among circ_0122396, miR-23a-3p, and MMP16. Results Circ_0122396 and MMP16 were down-regulated while miR-23a-3p was up-regulated in ARC. H2O2 constrained proliferation and GSH-PX level, promotes apoptosis and MDA level in HLECs, and overexpression of circ_0122396 attenuated these effects. miR-23a-3p was a direct target of circ_0122396, and MMP16 was a direct target of miR-23a-3p. The effect of circ_0122396 overexpression on H2O2-induced HLECs was reversed by miR-23a-3p, and MMP16 elevation overturned the impacts of miR-23a-3p in H2O2-induced HLECs. Conclusions Circ_0122396 may regulate the progression of ARC via the miR-23a-3p/MMP16 pathway in H2O2-stimulated HLECs, which may serve as a potentially valuable biomarker and novel therapeutic target for ARC.

Role of actin-binding proteins in cataract formation.

Actin has been implicated in lens opacification; however, the specific actin-related pathways involved in cataracts remain unelucidated. In this study, actin-related proteome changes and signaling pathways involved in the development of cataracts were evaluated. The anterior capsule and phacoemulsification (phaco) cassette contents were collected during cataract surgery from 11 patients with diabetic cataract (DC), 12 patients with age-related cataract (ARC), and seven patients with post-vitrectomy cataract (PVC). Untargeted, global identification and quantification of proteins was performed through liquid chromatography-mass spectrometry with the data-independent acquisition (DIA). In phaco cassette samples, proteins with significantly lower expression in ARC than in DC and PVC were involved in various pathways, including actin binding, actin cytoskeleton reorganization, actin filament capping, cortical actin cytoskeleton organization, and small GTPase-mediated signal transduction pathways. In anterior capsules, proteins with significantly lower expression in ARC than in DC and PVC were involved in actin binding and actin cytoskeleton reorganization pathways. Actin cytoskeleton and actin-binding proteins are involved in lens fiber elongation and differentiation. Rho GTPases contribute to actin cytoskeletal reorganization, and their inactivation is linked to abnormal lens fiber migration. These findings link actin binding to lens fiber integrity, lens opacification, and cataracts.

Rotational stability and refractive outcomes of a new hydrophobic acrylic toric intraocular lens

PurposeTo assess rotational stability and refractive outcomes of a new toric hydrophobic acrylic intraocular lens (IOL).DesignSingle-center, prospective, interventional clinical trial.MethodsA total of 130 eyes of 82 patients with age-related cataract and total corneal astigmatism of greater than 1.0 diopters (D) received a hydrophobic acrylic toric IOL Clareon CNW0T3-9. Baseline measurement for rotational stability evaluation was performed at the end of surgery (EOS), with the patient still supine on the operating table, using non-movable vessels as reference landmarks. Postoperative retroillumination pictures were taken at 1 h, 1 week, 1 month and 4–6 months postoperatively. Subjective manifest refraction was assessed at the 6 months follow-up visit.ResultsFinal results were obtained in 126 eyes of 80 patients. Mean absolute rotation from EOS to 6 months was 1.33 ± 2.00 [0.01, 19.80] degrees. Rotational stability values from EOS to 1 h, 1 h to 1 week, 1 week to 1 month and 1 month to 6 months were 0.86 ± 0.82 [0.00, 3.90], 1.06 ± 1.94 [0.00, 19.45], 0.47 ± 0.42 [0.00, 2.03] and 0.38 ± 0.40 [0.00, 2.56] degrees. Mean preoperative corneal astigmatism was 1.78 ± 0.83 [1.00, 4.76] D which changed to a mean postoperative refractive astigmatism of 0.33 ± 0.27 [0.00, 1.25] D at 6 months.ConclusionThe Clareon toric IOL presented very good rotational stability with a mean absolute rotation below 1.4° from EOS to 6 months. Only two IOLs rotated more than 5° with none of them requiring repositioning surgery. Refractive outcomes were satisfying with a mean residual refractive astigmatism below 0.50 D.Trial registrationRegistered at Clinicaltrials.gov NCT03803852; on May 17, 2022.

Comparative Accuracy of Barrett Integrated Keratometry Toric Calculator With Predicted Versus Measured Posterior Corneal Astigmatism.

To compare the prediction accuracy of the Barrett toric calculator using standard or integrated keratometry (IK) mode in combination with predicted or measured posterior corneal astigmatism (PCA) in a group of patients with cataract implanted with non-toric IOLs. In this retrospective clinical cohort study, the medical records of patients with age-related cataract who underwent phacoemulsification with the implantation of an aspheric monofocal IOL were reviewed. Four methods, including standard keratometry with predicted PCA (PPCA), IK combined with predicted PCA (IK-PPCA), and IK combined with measured PCA derived from IOLMaster 700 (Carl Zeiss Meditec AG) or CASIA2 (Tomey) (IK-MMPCA or IK-CMPCA), were applied to the Barrett toric calculator to calculate the predicted residual astigmatism. The mean absolute prediction error (MAPE), centroid of the prediction error, and proportion of eyes within the prediction error of ±0.50, ±0.75, and ±1.00 diopters (D) were all ciphered out from the four methods, respectively. Data from 129 eyes of 129 patients were included in this study. The MAPE of the IK-PPCA method (0.57 ± 0.36 D) was significantly smaller than that of the PPCA (0.62 ± 0.38 D) and IK-CMPCA (0.63 ± 0.46 D) methods (P = .048 and .014, respectively). There were no significant differences in the centroid vectors of prediction errors and predictability rates among the four methods (all P > .05). In the current version of the Barrett toric calculator, the predictive accuracy of the IK mode incorporating PPCA was slightly superior to using the standard keratometry mode or incorporating MPCA. [J Refract Surg. 2024;40(7):e453-e459.].

Association of CUL4B with the pathogenesis of age-related cataract.

Age-related cataract (ARC) is the most common cause of visual impairment and blindness in older adults. However, the role of CUL4B in the ARC remains unclear. Therefore, we investigated CUL4B expression and its effects on apoptosis. CUL4B expression levels were detected by a quantitative real-time polymerase chain reaction from the anterior lens capsules of patients with ARC and HLE-B3 cells treated with different concentrations of H2O2. CUL4B expression was silenced by siRNA transfection to evaluate apoptosis. CUL4B and apoptotic proteins B cell lymphoma 2 (Bcl-2), myeloid cell leukemia 1 (Mcl-1), caspase-3, cleaved caspase-3, Bax, Bak, and Bid were assessed using western blot analysis. Apoptosis was monitored using the TUNEL assay. CUL4B expression was downregulated in the anterior lens capsules (P < 0.0001) and H2O2-treated HLE-B3 cells (P = 0.0405). CUL4B protein levels were significantly lower in 100µmol/L (P = 0.0012) and 200µmol/L (P = 0.0041) H2O2-treated HLE-B3 cells than in the untreated cells. CUL4B expression was significantly knocked down at the mRNA (P = 0.0043) and protein levels (P = 0.0002) in HLE-B3 cells. Bcl-2 (P = 0.0199), Mcl-1 (P = 0.0042), and caspase-3 (P = 0.0142) were significantly downregulated, whereas cleaved caspase-3 (P = 0.0089) and Bak (P = 0.009) were significantly upregulated in the knockdown group. The TUNEL assay showed a greater induction of apoptosis. CUL4B downregulation promotes the apoptosis of lens epithelial cells. Our study may help in understanding the role of CUL4B in ARC pathogenesis.

Clinical and statistical characteristics of primary open-angle glaucoma in patients with age-related cataract in the Khabarovsk territory

Clinical and statistical characteristics of primary open-angle glaucoma in patients with age-related cataract in the Khabarovsk territory

Characterization of βB2-crystallin tryptophan mutants reveals two different folding states in solution.

Conserved tryptophan residues are critical for the structure and the stability of β/γ-crystallin in the lenses of vertebrates. During aging, in which the lenses are continuously exposed to ultraviolet irradiation and other environmental stresses, oxidation of tryptophan residues in β/γ-crystallin is triggered and impacts the lens proteins to varying degrees. Kynurenine derivatives, formed by oxidation of tryptophan, accumulate, resulting in destabilization and insolubilization of β/γ-crystallin, which correlates with age-related cataract formation. To understand the contribution of tryptophan modification on the structure and stability of human βB2-crystallin, five tryptophan residues were mutated to phenylalanine considering its similarity in structure and hydrophilicity to kynurenine. Among all mutants, W59F and W151F altered the stability and homo-oligomerization of βB2-crystallin-W59F promoted tetramerization whereas W151F blocked oligomerization. Most W59F dimers transformed into tetramer in a month, and the separated dimer and tetramer of W59F demonstrated different structures and hydrophobicity, implying that the biochemical properties of βB2-crystallin vary over time. By using SAXS, we found that the dimer of βB2-crystallin in solution resembled the lattice βB1-crystallin dimer (face-en-face), whereas the tetramer of βB2-crystallin in solution resembled its lattice tetramer (domain-swapped). Our results suggest that homo-oligomerization of βB2-crystallin includes potential inter-subunit reactions, such as dissociation, unfolding, and re-formation of the dimers into a tetramer in solution. The W>F mutants are useful in studying different folding states of βB2-crystallin in lens.

Ocular Disease Recognition Based on Deep Learning: A Comprehensive Review

This review article represents a major advance in the field of medical imaging and ophthalmology by exploring the critical role of deep learning in the detection and diagnosis of eye diseases. Early and accurate diagnosis becomes essential due to the frequency of ocular disorders that pose a significant risk to vision, including diabetic retinopathy, age-related macular degeneration, glaucoma, and cataracts. The need for more reliable automated solutions is highlighted by the limitations of traditional methods, despite their benefits, which include reliance on small datasets and manual feature analysis. Deep learning, a subset of machine learning, is becoming evident as a powerful tool that can interpret complex medical images and improve diagnostic accuracy without the need to extract human features. This article explores the evolution of deep learning applications in ophthalmology, highlighting the difficulties encountered such as interpretability of models and data quality and the creative solutions that have been found to overcome them. We highlight the revolutionary impact of deep learning in eye disease detection through an in-depth analysis of recent developments, providing insight into potential future research avenues that may further improve patient care in ophthalmology.

The burden, causes, and determinants of blindness and vision impairment in Asia: An analysis of the Global Burden of Disease Study.

Asia accounts for more than half of the world's population and carries a substantial proportion of the global burden of blindness and vision impairment. Characterising this burden, as well as its causes and determinants, could help with devising targeted interventions for reducing the occurrence of blindness and visual impairment. Using the Global Burden of Disease Study 2019 database, we retrieved data on the number of disability-adjusted life years (DALYs); crude and age-standardised rates; and the prevalence (with 95% uncertainty intervals (95%UIs)) of blindness and vision loss due to six causes (age-related macular degeneration, cataracts, glaucoma, near-vision impairment, refractive error, and other vision loss) for Asian countries for the period between 1990 and 2019. We defined DALYs as the sum of the years lost due to disability and years of life lost, and calculated age-standardised figures for the number of DALYs and prevalence by adjusting for population size and age structure. We then evaluated the time trend of the disease burden and conducted subgroup analyses by gender, age, geographic locations, and socio-demographic index (SDI). In 2019, the DALYs and prevalence of blindness and vision loss had risen by 90.1% and 116% compared with 1990, reaching 15.84 million DALYs (95% UI = 15.83, 15.85) and 506.71 million cases (95% UI = 506.68, 506.74). Meanwhile, the age-standardised rate of DALYs decreased from 1990 to 2019. Cataracts, refractive error, and near vision impairment were the three most common causes. South Asia had the heaviest regional disease burden (age-standardised rate of DALYs = 517 per 100 000 population; 95% UI = 512, 521). Moreover, the burden due to cataracts ranked high in most Asian populations. Being a woman; being older; and having a lower national SDI were factors associated with a greater vision loss burden. The burden due to vision loss remains high in Asian populations. Cataracts, refractive error, and near vision loss were the primary causes of blindness and vision loss. Greater investment in ocular disease prevention and care by countries with lower socioeconomic status is needed, as well as specific strategies targeting cataract management, women and the elderly.

Levels of asymmetric dimethylarginine in plasma and aqueous humor: a key risk factor for the severity of fibrovascular proliferation in proliferative diabetic retinopathy.

Proliferative diabetic retinopathy (PDR) is a common diabetes complication, significantly impacting vision and quality of life. Previous studies have suggested a potential link between arginine pathway metabolites and diabetic retinopathy (DR). Connective tissue growth factor (CTGF) plays a role in the occurrence and development of fibrovascular proliferation (FVP) in PDR patients. However, the relationship between arginine pathway metabolites and FVP in PDR remains undefined. This study aimed to explore the correlation between four arginine pathway metabolites (arginine, asymmetric dimethylarginine[ADMA], ornithine, and citrulline) and the severity of FVP in PDR patients. In this study, plasma and aqueous humor samples were respectively collected from 30 patients with age-related cataracts without diabetes mellitus (DM) and from 85 PDR patients. The PDR patients were categorized as mild-to-moderate or severe based on the severity of fundal FVP. The study used Kruskal-Wallis test to compare arginine, ADMA, ornithine, and citrulline levels across three groups. Binary logistic regression identified risk factors for severe PDR. Spearman correlation analysis assessed associations between plasma and aqueous humor metabolite levels, and between ADMA and CTGF levels in aqueous humor among PDR patients. ADMA levels in the aqueous humor were significantly greater in patients with severe PDR than in those with mild-to-moderate PDR(P=0.0004). However, the plasma and aqueous humor levels of arginine, ornithine, and citrulline did not significantly differ between mild-to-moderate PDR patients and severe PDR patients (P>0.05). Binary logistic regression analysis indicated that the plasma (P=0.01) and aqueous humor (P=0.006) ADMA levels in PDR patients were risk factors for severe PDR. Furthermore, significant correlations were found between plasma and aqueous humor ADMA levels (r=0.263, P=0.015) and between aqueous humor ADMA and CTGF levels (r=0.837, P<0.001). Elevated ADMA levels in plasma and aqueous humor positively correlate with the severity of FVP in PDR, indicating ADMA as a risk factor for severe PDR.

Effect of femtosecond laser-assisted phacoemulsification on corneal endothelium and prognosis of diabetic patients with cataract with different nuclear hardness

Objective: To assess the impact of femtosecond laser-assisted phacoemulsification on corneal endothelial characteristics and prognosis among patients with type 2 diabetes and age-related cataracts, considering varying nuclear hardness. Methods: This non-randomized controlled trial involved 161 patients (161 eyes) with type 2 diabetes undergoing cataract extraction at Weifang Eye Hospital between March 2020 and December 2022. The cohort comprised 73 males and 88 females, with an average age of (65.9±5.23) years. Based on patient preference, 101 individuals underwent conventional phacoemulsification (group A), while 60 chose femtosecond laser-assisted phacoemulsification (group B). Patients were further stratified based on Emery-Little grade of lens nuclei into A1/B1 (grade Ⅰ and Ⅱ), A2/B2 (grade Ⅲ), and A3/B3 (grade Ⅳ) subgroups. The study compared effective phacoemulsification time (EPT), cumulative energy release of phacoemulsification (CDE), central corneal thickness (CCT), endothelial cell density (ECD), coefficient of variation (CV), and hexagon cell ratio (HEX) before and after surgery at 1 day, 1 week, 1 month, and 3 months. Results: The intraoperative EPT of patients in groups A and B were (6.52±4.93) and (5.63±4.31)s, respectively, and the CDE were 11.57%±5.21% and 10.68%±6.02%, respectively. The differences between them were not statistically significant (all P>0.05).There were no significant differences in EPT and CDE between groups A1 and B1 (all P>0.05), and there were statistically significant differences between groups A2 and B2, A3 and B3 (all P<0.05).The postoperative CCT was increased in both groups.There were no statistically significant differences in CCT between A1 and B1 groups at different time after surgery (all P>0.05), and there were statistically significant differences in CCT between A2 and B2, A3 and B3 groups at 1 day and 1 week after surgery (all P<0.05), and group B was significantly lower than group A.There was no significant difference between 1 month and 3 months after surgery (P>0.05).ECD was reduced in both groups.There was no statistically significant difference in ECD at different time of operation between A1 and B1 groups (all P>0.05), while there was statistically significant difference in ECD at 1 day, 1 week, 1 month and 3 months after operation in A2 and B2, A3 and B3 groups (all P<0.05). Group B was significantly better than group A. There was no significant difference in coefficient of variation and HEX between the two groups at different time after surgery (P>0.05). Conclusion: Femtosecond laser-assisted phacoemulsification demonstrates benefits in preserving corneal endothelial cells, reducing early postoperative corneal edema, and minimizing corneal injury in type 2 diabetes patients with cataracts of high nuclear hardness.

Effect of cervical pillow in phacoemulsification surgery for age-related cataract patients: a prospective randomized controlled study.

To explore the application effect of cervical pillow in phacoemulsification surgery for age-related cataract patients. 104 cases of age-related cataract patients admitted to our hospital in June 2023 were enrolled and divided into the control group (traditional supine position) and the experimental group (the cervical pillow supine position) by the digital parity method (52 cases per group). The two groups were evaluated for the discomfort score, the satisfaction of patients and doctors, the head displacement rate, the number of displacement, the operation time and the time of body position during the operation and after the operation. There was no significant difference in the gender (P = 0.84), age (P = 0.86), course of disease (P = 0.82) and the time spent on position placement (P = 0.15) of the two groups. The patient in the experimental group had lower discomfort score (P = 0.0001), higher patients satisfaction (P = 0.0001) and higher doctors satisfaction (P = 0.0001) than patients in the control group. There was no significant difference between the experimental group and the control group in the proportion of intraoperative (P = 0.36) and postoperative pain (P = 0.65). Besides, the number of head transfers (P = 0.001), number of head shifts (P = 0.0001), the surgical time (P = 0.0001) and laparoscopic time (P = 0.0001) in the experimental group were significantly lower than those in the control group. The additional cervical pillow for age-related cataract patients in the traditional supine position during the operation will not increase the preparation time before the operation, but will help improve the patient satisfaction, improve the comfort and maintain a good position of the operative eye field, bringing obvious comfort and smooth operation for the surgeon in the operation, thus reducing the risk of the operation, shortening the operation time.

Plant-based diets and the risk of age-related cataract: a case-control study

PurposeCataract, or lens opacification, is a major public health burden accounting for more than half of all blindness worldwide. Plant-based dietary indices provide a unique approach to investigating a modifiable risk for age-related cataracts (ARC). The purpose of this study was to investigate the association between plant-based diet indices and risk of ARC.Design/methodology/approachThis case-control study was conducted on 97 patients with newly diagnosed ARC and 198 healthy people (as a control group) in Iran. Convenience sampling and a food frequency questionnaire were used. Three plant-based dietary indices were used based on the health promoting qualities of food items, the overall plant-based diet index (PDI), healthful plant-based diet index (H-PDI) and unhealthful plant-based diet index (U-PDI) which comprised refined carbohydrates and highly processed foods. The plant-based dietary indices were used to investigate relationships with risk of ARC.FindingsAfter adjusting for potential covariates, no significant association between a higher adherence to O-PDI and risk of ARC. As well, a higher adherence to H-PDI was inversely associated with the risk of ARC (OR = 0.35,95%CI:0.16–0.78). In contrast, there was a significant positive association between a higher adherence to U-PDI and the risk of ARC (OR = 3.67,95%CI:1.66 – 8.15).Originality/valueThe findings of this study have underscored the potential impact of the quality of plant-based food selections on the likelihood of developing ARC. Therefore, adopting a plant-based diet that is rich in nutrient-dense plant-based foods while being low in unhealthy options may have the potential to reduce the risk of ARC.

LncRNA MEG3 regulates ferroptosis of lens epithelial cells via PTBP1/GPX4 axis to participate in age-related cataract.

Age-related cataract (ARC) is regarded as the principal cause of vision impairment among the aged. The regulatory role of long noncoding RNAs (LncRNAs) in ARC remains unclear. The lncRNA maternally expressed gene 3 (MEG3) has been reported to promote ARC progression, and the underlying mechanism was further investigated in this study. Lens epithelium samples were collected to verify the expression of MEG3. Lens epithelial cells (LECs) were treated with H2O2 to mimic microenvironment of ARC in vitro. Cell viability, reactive oxygen species, and ferroptosis were evaluated during the in viro experiments. In the present work, lncRNA MEG3 was highly expressed in ARC group, compared with normal group. MEG3 was induced, cell viability and glutathione peroxidase 4 (GPX4) level were inhibited, and ferroptosis was promoted in H2O2 treated LECs. LncRNA MEG3 silence reversed the effects of H2O2 on viability and ferroptosis in LECs. Thereafter, lncRNA MEG3 was found to bind to PTBP1 for GPX4 degradation. Silencing of GPX4 reversed the regulation of lncRNA MEG3 inhibition in H2O2-treated LECs. To sum up, lncRNA MEG3 exhibited high expression in ARC. In H2O2-induced LECs, inhibition of lncRNA MEG3 accelerated cell viability and repressed ferroptosis by interaction with PTBP1 for GPX4 messenger RNA decay. Targeting lncRNA MEG3 may be a novel treatment of ARC.

Animal model for in-vivo Nuclear Cataract. Lens hardness and elasticity assessment.

Age-related cataract is the most frequent cause of blindness in the world being responsible for 48% of blindness and affecting more than 10% of the working population. Currently there is no objective data of the lens biomechanical properties so the process by which the cataract affects the lens's properties (e.g. hardness and elasticity) is still unclear.A modified animal model was produced to create different severities of nuclear cataract. Different doses of sodium selenite were injected in two different moments of the rat’ eyes maturation resulting in 12, 13 and 11 rats with incipient, moderate and severe cataract, respectively. The nucleus and cortex's hardness and the stiffness were measured using NanoTest™.Statistically significant differences were found between healthy and cataractous lenses. Statistically significant differences were also found between the different nuclear cataract degrees (p = 0.016), showing that the lens’ hardness increases with cataract formation. The nucleus shows a higher hardness increase with cataract formation (p = 0.049).The animal model used in this study allowed for the first time the characterization of the lens's hardness and elasticity in two regions of the lens, in healthy and cataractous lenses.

Feasibility of shear wave elastography for evaluating lens stiffness in patients with age-related cataracts: A quantitative analysis

BackgroundShear wave elastography (SWE) is a novel imaging technique that provides quantitative assessments of tissue stiffness. This non-invasive method offers real-time, quantitative measurements and has been widely applied to various tissues, providing valuable diagnostic insights. PurposeThis study aimed to investigate the feasibility of using SWE to evaluate the stiffness of the lens in patients with age-related cataracts. Materials and methodsA comparative analysis involving 92 patients diagnosed with age-related cataracts and 39 healthy controls was conducted. Lens stiffness was quantified using SWE measurements. The lens nucleus of all participants was graded based on the Lens Opacities Classification System II (LOCS II). Correlations between the stiffness of the lens and age were also analyzed. ResultsThe study indicates that both the stiffness of the lens and the lens nucleus were significantly higher in patients with age-related cataracts compared to healthy controls (P < 0.001). In patients with age-related cataracts, although lens nucleus stiffness variations across different grades of cataract severity were not statistically significant, all grades displayed increased stiffness relative to healthy controls. Additionally, a significant positive correlation between lens stiffness and age was observed in all participants (P < 0.001). ConclusionSWE appears to be a promising imaging technique for quantitatively assessing the mechanical characteristics of the lens in patients with age-related cataracts.

Characterization of mechanical stress in the occurrence of cortical opacification in age-related cataracts using three-dimensional finite element model of the human lens and RNA-seq

Cataract is the leading cause of blindness across the world. Age-related cataract (ARC) is the most common type of cataract, but its pathogenesis is not fully understood. Using three-dimensional finite element modeling combining experimental biotechnology, our study demonstrates that external forces during accommodation cause mechanical stress predominantly in lens cortex, basically matching the localization of opacities in cortical ARCs. We identified the cellular senescence and upregulation of PIEZO1 mRNA in HLECs under mechanical stretch. This mechano-induced senescence in HLECs might be mediated by PIEZO1-related pathways, portraying a potential biomechanical cause of cortical ARCs. Our study updates the fundamental insight towards cataractogenesis, paving the way for further exploration of ARCs pathogenesis and nonsurgical treatment.

Sulforaphane and ophthalmic diseases.

Sulforaphane (SFN) is an organosulfur compound categorized as an isothiocyanate (ITC), primarily extracted from cruciferous vegetables like broccoli and cabbage. The molecular formula of sulforaphane (SFN) is C6H11NOS2. SFN is generated by the hydrolysis of glucoraphanin (GRP) through the enzyme myrosinase, showing notable properties including anti-diabetic, anti-inflammatory, antimicrobial, anti-angiogenic, and anticancer attributes. Ongoing clinical trials are investigating its potential in diseases such as cancer, neurodegenerative diseases, diabetes-related complications, chronic kidney disease, cardiovascular disease, and liver diseases. Several animal carcinogenesis models and cell culture models have shown it to be a very effective chemopreventive agent, and the protective effects of SFN in ophthalmic diseases have been linked to multiple mechanisms. In murine models of diabetic retinopathy and age-related macular degeneration, SFN delays retinal photoreceptor cell degeneration through the Nrf2 antioxidative pathway, NF-κB pathway, AMPK pathway, and Txnip/mTOR pathway. In rabbit models of keratoconus and cataract, SFN has been shown to protect corneal and lens epithelial cells from oxidative stress injury by activating the Keap1-Nrf2-ARE pathway and the Nrf-2/HO-1 antioxidant pathway. Oral delivery or intraperitoneal injection at varying concentrations are the primary strategies for SFN intake in current preclinical studies. Challenges remain in the application of SFN in eye disorders due to its weak solubility in water and limited bioavailability because of the presence of blood-ocular barrier systems. This review comprehensively outlines recent research on SFN, elucidates its mechanisms of action, and discusses potential therapeutic benefits for eye disorders such as age-related macular degeneration (AMD), diabetic retinopathy (DR), cataracts, and other ophthalmic diseases, while also indicating directions for future clinical research to achieve efficient SFN treatment for ophthalmic diseases.

Comparison of Different Intraocular Lens Power Calculation Formulas in Eyes With Primary Angle Closure.

Prospective case series. This prospective study determines which formulas can best predict the refractive outcome in patients with primary angle closure disease (PACD) after cataract surgery. To compare the accuracy of 6 intraocular lens power calculation formulas, Barrett Universal II (BU II), Haigis, Hoffer Q, Holladay I, Kane and SRK/T, in eyes with PACD. Patients diagnosed with PACD and cataracts and who met the indication for cataract surgery were enrolled in the study. Six intraocular lens power calculation formulas were used to calculate the refractive diopter. The percentage of eyes with prediction error (PE) within ±0.50 D and the median absolute PE were compared to determine the accuracy of different formulas in patients with PACD. Subgroup analysis was performed according to axial length (AL). The accuracy of BU II was compared between patients with PACD and patients with age-related cataracts. One hundred five patients (105 eyes) with PACD and 35 patients (35 eyes) with age-related cataracts were enrolled in the study. Haigis, Kane, and BU II formula achieved a comparable outcome and outperformed over the other 3 formulas in patients with PACD. Subgroup analysis showed that the group with long AL has lower values of median absolute PE. PE was significantly positively correlated with AL and negatively correlated with relative lens position when calculated using BU II and Kane. Haigis, Kane, and BU II formula achieved a comparable outcome and outperformed over the other 3 formulas in patients with PACD.