Anterior Lens Capsule Research Articles

Исследование предоперационной симметрии дистанции «экватор хрусталика – цилиарные отростки» у пациентов с сочетанием возрастной катаракты с клиническими проявлениями инволюционной соединительнотканной дисплазии

Purpose. Study of state of the Zonule of Zinn in patients with combination senile cataract with systemic involutional connective tissue dysplasia. Material and methods. 97 patients (97 eyes) – combination senile cataract with involutional pathology in connective tissue (the main group). 1st subgroup: 31 patients with kyphoscoliotic deformity of the 3d and 4th degree (classification by V.D. Chaklin (1973)); 2nd subgroup – 66 patients with chronic venous insufficiency 2nd and 3d degree (the CEAP classification) against the background of varicose veins of the lower extremity. Patients of both subgroups were comparable in terms of cataract stages and nuclear cataract lens density in Buratto classification. The control group – 55 patients (55 eyes) similar sex and age with senile cataracts without involutional connective tissue pathology. We estimated the symmetry of distance «lens equator – ciliary processes» in 2 meridians: at 6 and 12 hours. The presence of asymmetry of 0.3 mm or more was sign of weak zonular support (according to ultrasonic biomicroscopy). Results. In the control group, the distance was 0.3 mm in 3 eyes (5%), with intraoperative formation of folds in the anterior capsule. In 10 eyes of the 1st subgroup of the main group (32%), the presence of distance asymmetry was revealed: intraoperative, signs of subluxation of the lens of the 1st degree were detected in 7 eyes. In the 2nd subgroup of the main group, distance asymmetry was detected in 24 eyes (37%). Folded anterior lens capsule was determined intraoperative in 14 eyes (21%) during anterior capsulorhexis and lens mobility during nucleus emulsification. Conclusion. A statistically significant difference in frequency of asymmetries of distances «lens equator – ciliary processes» in 2 opposite meridians was revealed between groups of patients with senile cataract against the background of systemic somatic involutional pathology of connective tissue and without it (35% vs. 5%; p < 0.01). Keywords: senile cataract, Zonule of Zinn, involutional changes in connective tissue, ultrasound biomicroscopy

Endoplasmic Reticulum Stress and the Lysosomal Pathway Play Crucial Roles in the Progression of βB2-Crystallin Mutation-Induced Congenital Cataracts inMice.

Congenital cataract is a major cause of visual impairment and childhood blindness; however, its underlying mechanism remains unclear. Here, we aimed to identify the roles of endoplasmic reticulum stress (ERS), lysosomal pathway, and lens capsule fibrosis during the progression of βB2-crystallin mutation-induced congenital cataract in mice. BetaB2-W151C knock-in mice were generated using the CRISPR/Cas9 system. Lens opacity was assessed with a slit-lamp biomicroscopy and dissecting microscope. Transcriptional profiles of the lenses in W151C mutant and wild-type (WT) control mice were detected at 3 months of age. Immunofluorescence of lens anterior capsule was photographed with a confocal microscope. Real-time PCR and immunoblot were used to detect gene mRNA and protein expressions, respectively. BetaB2-W151C knock-in mice developed progressive bilateral congenital cataracts. At 2 to 3 months of age, lens opacity rapidly progressed to complete cataracts. Additionally, multilayered LEC plaques developed beneath the lens anterior capsule in homozygous mice at 3 months of age, and severe fibrosis was observed in the whole lens capsule at 9 months of age. Microarray analysis of whole genome transcriptomics and the validation results of real-time PCR revealed that genes of ERS, the lysosomal pathway, apoptosis, and cell migration and fibrosis were significantly upregulated in βB2-W151C mutant mice during the accelerated development of cataract. Moreover, the syntheses of various crystallins stagnated in βB2-W151C mutant mice. ERS, the lysosomal pathway, apoptosis, and fibrosis all contributed to the accelerated development of congenital cataract. The inhibition of ERS and lysosomal cathepsins may be promising therapeutic strategies for congenital cataract.

Mechanical protective effect of lens anterior capsule disc on corneal endothelial cells during femtosecond laser-assisted cataract surgery in a rabbit model

PurposeTo evaluate the effects of a novel technique using an isolated lens anterior capsule disc (LACD) to protect corneal endothelial cells in rabbit eyes during femtosecond laser-assisted cataract surgery.MethodsExperimental study. 40 rabbits were divided into endothelium-protected (experimental) and control groups, with 20 rabbits in each group. In the experimental group, after femtosecond laser capsulotomy, the isolated capsule disc was lifted to the corneal endothelium by an ophthalmic viscosurgical device. The endothelium was damaged for 1 min with an ultrasonic probe. The control group underwent the same surgery, except that the disc was removed immediately after capsulorhexis. Corneal endothelioscopy was performed preoperatively and on postoperative days (PODs) 3 and 7 to observe endothelial cell counts (ECC) and endothelial cell loss rate. Central corneal thickness (CCT) was measured before and at PODs 1, 3 and 7.ResultsThere were 3.59%±1.88% (p < 0.001) and 2.92%±2.14% (p < 0.001) loss of ECC in experimental group at POD3 and POD7, respectively, while those in the control group were 11.62%±7.43% and 10.34%±5.77%, respectively. On POD 1, the difference in central corneal thickness was significant(P = 0.019) between the two groups. At POD 3 and POD 7, CCT was not significantly different (P = 0.597;0.913) between the two groups.ConclusionsThe isolated LACD technique significantly reduced damage to the endothelium caused by ultrasonic energy and protects corneal endothelial cells during phacoemulsification.

BMP-4 and BMP-7 Inhibit EMT in a Model of Anterior Subcapsular Cataract in Part by Regulating the Notch Signaling Pathway.

The proliferation, migration, and epithelial-mesenchymal transition (EMT) of lens epithelial cells (LECs) are believed to be the pathological mechanisms underlying anterior subcapsular cataract (ASC). Bone morphogenetic proteins (BMPs) inhibit transforming growth factor-beta (TGF-β)-induced fibrosis in the lens. Herein, we aimed to further clarify the roles of BMP-4/BMP-7 in the progression and the underlying mechanisms of fibrotic cataract. BMP-4/BMP-7, TGF-β2, jagged-1 peptide, or DAPT were applied in a mouse injury-induced ASC model and in the human LEC cell line SRA01/04. The volume of opacity was examined by a slit lamp and determined by lens anterior capsule whole-mount immunofluorescence. Global gene expression changes were assessed by RNA sequencing, and the levels of individual mRNAs were validated by real-time PCR. Protein expression was determined by the Simple Western sample dilution buffer. Cell proliferation was examined by CCK8 and EdU assays, and cell migration was measured by Transwell and wound healing assays. Anterior chamber injection of BMP-4/BMP-7 significantly suppressed subcapsular opacification formation. RNA sequencing of the mouse ASC model identified the Notch pathway as a potential mechanism involved in BMP-mediated inhibition of ASC. Consistently, BMP-4/BMP-7 selectively suppressed Notch1 and Notch3 and their downstream genes, including Hes and Hey. BMP-4/BMP-7 or DAPT suppressed cell proliferation by inducing G1 cell cycle arrest. BMP-4/BMP-7 also inhibited TGF-β2-induced cell migration and EMT by modulating the Notch pathway. BMP-4/BMP-7 attenuated ASC by inhibiting proliferation, migration, and EMT of LECs via modulation of the Notch pathway, thereby providing a new avenue for ASC treatment.

Ubiquitination of Ku70 by Parkin promotes apoptosis of lens epithelial cells.

Oxidative damage-triggered apoptosis in lens epithelial cells is considered as a main risk factor in the pathogenesis of age-related cataracts. Ku70 is a key factor in the DNA repair process of double-strand breaks. In the present study, we aimed to investigate the role of Ku70 and its related E3 ubiquitin ligase in lens epithelial cell apoptosis. The levels of Ku70 in the anterior lens capsules of human cataracts and Emory mice were lower compared to controls. H2 O2 treatment resulted in decreased expression of Ku70 through accelerating Ku70 ubiquitination. Parkin, an E3 ubiquitin ligase, could interact with Ku70 and promote the ubiquitination and degradation of this protein. In addition, ubiquitinated Ku70 was regulated by ubiquitin-proteasome, autophagy-lysosome and mitophagy pathways. Ectopic expression of Ku70 protected SRA01/04 cells from H2 O2 -induced apoptosis, whereas silencing Ku70 exhibited the opposite trend. Co-transfected with Parkin non-ubiquitinatable Ku70 mutant could maintain its anti-apoptosis ability, whereas wild-type Ku70 failed. Moreover, Ku70 might facilitate mitochondrial fusion by increasing the expression of Mitofusin 1/2. The present study revealed that Parkin-mediated Ku70 ubiquitination facilitated H2 O2 -induced lens epithelial cell apoptosis through alleviating mitochondrial fusion, which could provide potential targets for age-related cataract treatment.

Prevalence and outcome of lens capsule disruption in routine canine cataract surgery: A retrospective study of 520 eyes (2012-2019).

To investigate the prevalence and surgical outcome of lens capsule disruption (LCD) in dogs undergoing cataract removal. Medical records of 924 eyes undergoing phacoemulsification were analyzed retrospectively. Routine cataract surgeries with or without LCD were included. Any LCD other than routine anterior capsulorhexis was defined as LCD and classified according to location and etiology. Odds ratios (OR) were calculated for maintaining vision, implantation of an artificial intraocular lens (IOL), and enucleation. In total, 520 eyes were included. A LCD occurred in 145 eyes (27.8%; 145/520) and affected the posterior (85.5%; 124/145), anterior (6.2%; 9/145), and equatorial lens capsule (4.8%; 7/145) and at multiple locations (3.4%; 5/145). The etiology of the LCD was spontaneous preoperative in 41 eyes (28.3%; 41/145), accidental intraoperative in 57 eyes (39.3%; 57/145), and planned in 47 eyes (32.4%; 47/145). Disruption did not increase the odds of enucleation (OR = 1.48, 95% confidence interval [CI] 0.56-3.67; p = .36). The presence of LCD significantly increased the risk of losing vision 1 year post-operatively (OR = 8.17, 95% CI 1.41-84.93; p = .007) associated with retinal detachment. However, this was not present at 2 years follow-up or in PCCC cases at any time point. An IOL was implanted in 108 eyes (108/145; 75.2%) with LCD and in 45/47 (95.7%) eyes with a PCCC. Increased surgeon awareness of possible intraoperative, accidental LCDs is important, as LCDs were relatively common and associated with increased odds for vision loss after 1 year in the present study. A prospective study investigating the causes of intraoperative, accidental LCD is warranted.

Surgical outcomes of complicated cataract with pediatric trematode granulomatous uveitis.

To describe the clinical characteristics and surgical outcomes of complicated cataract with pediatric trematodal granulomatous uveitis (TGU). Patients of cataract with TGU in the membranous (inactive) stage underwent cataract surgery with intraocular lens (IOL) implantation. Preoperative history and ophthalmic examination were conducted for all cases, whereas Schimphlug imaging and corneal topography were done for some patients. Postoperative follow up was done on the 1st, 2nd, and 5th postoperative days after surgery. Then, it was done at least at one, three, and six months postoperatively. Intraoperative and postoperative complications and the methods of their management were reported. Twelve eyes of 12 male children were included in this study ranging from 8 to 16y. The mean best corrected Snellen visual acuity (BCVA) was significantly improved from 0.09±0.06 preoperatively to 0.37±0.11 at the final visit 6mo postoperatively (P<0.001). Schimphlug imaging and corneal topography showed flattening of the anterior surface of the inferior cornea. Intraoperative difficulties and complications included the poor dilatability of the drown down pupil, strong posterior synechia between the anterior lens capsule and the iris at the site of the inferior retrocorneal vascularized membrane and hyphema. All cases underwent primary hydrophobic IOL implantation. Surgery for this type of cataract is relatively safe and effective. It is associated with some specific difficulties and complications that should be considered during surgery and follow up.

Light and electron microscopic features of preclinical pseudoexfoliation syndrome.

This study sought to explore the features of the anterior lens capsule in patients with preclinical pseudoexfoliation syndrome (pPEX) via light microscopy (LM) and transmission electron microscopy (TEM). Cross-sectional, prospective, and observational case series. We recruited consecutive patients with and without pPEX who underwent routine cataract surgery at Ramathibodi Hospital, between April 2018 and November 2020. pPEX can be characterized by pigmented spoke-wheel deposition (P) on the anterior lens capsule, midperiphery cleft/lacunae (C), faint central disc present within the photopic pupil (D), white-spoke pattern (W) noted at the midperiphery, and a combination of at least two signs (Co). LM and TEM were used to examine anterior lens capsule specimens for the presence of characteristic pseudoexfoliation material (PXM). The features of the anterior lens capsule in pPEX explored via LM and TEM were recorded. This study included a total of 96 patients (101 excised anterior lens capsules); among them, 34 (35 excised anterior lens capsules) exhibited pPEX signs (pPEX group) but 62 (66 excised anterior lens capsules) did not (control group). The patients had a mean age of 74 ± 7 (range, 58-89) years. LM and TEM revealed no definite PXM in any patient. In the pPEX group, LM analysis identified two capsule specimens with suspected PXM; PXM precursors were observed in 1 of the 34 excised capsule specimens analyzed via TEM. Furthermore, 39 eyes (59.09%) exhibited signs of true exfoliation syndrome (TEX) in LM analysis (12.82%, 25.64%, 10.26%, 10.26%, and 41.03% for patients exhibiting P, D, C, W, and Co, respectively). However, no TEX signs were observed in the control group. We found that the anterior lens capsules exhibiting C and D were significantly associated with TEX (odds ratio = 5.4 and 7.9; P = 0.007 and 0.004, respectively). LM analysis revealed no definite PXMs were detected in the excised anterior lens capsules, whereas TEM analysis showed PXM precursors in one specimen (2.94%). Notably, a significant association was observed between C and D signs and TEX.

Management of Pediatric Traumatic Cataract With An Open Globe Injury

Introduction: Traumatic cataract is one of the leading causes of monocular blindness in children. The management of pediatric traumatic cataract is challenging; the growing size of the affected eyes and the risk of amblyopia further complicate things. The timing of cataract removal and IOL implantation remain controversial until today. Case Report: A thirteen-years-old boy came with his left eye punctured by a pencil tip. He came in with a visual acuity of 1/300, a full-thickness 5 mm paracentral corneal laceration and traumatic cataract. The patient went through a two-step surgery. Cataract surgery and IOL implantation was conducted one week following corneal laceration suture. Discussion: Two-step surgery was performed on this patient with consideration being cataract removal performed when the inflammation of the eye was subside and also a more accurate IOL calculation. One study stated, even with 43.4% of patient’s anterior capsule ruptures, it would postponed cataract surgery for 2 days up to 6 months. In this case, a week after first surgery, it revealed anterior capsule rupture and the lens material was touching corneal endothelium. Therefore, lensectomy was performed because it touches the corneal endothelium causing further damage Conclusion: The two-step procedure performed was a preferable surgery for a traumatic cataract in a quiet eye, because it has better potential for visual improvement and IOL calculation. However, since the anterior lens capsule ruptured and the lens material prolapsed into the anterior chamber, it would have been even better to perform lensectomy as an early procedure to prevent inflammation.

Age-related cataract: GSTP1 ubiquitination and degradation by Parkin inhibits its anti-apoptosis in lens epithelial cells

PurposeOxidative stress-induced apoptosis of lens epithelial cells (LECs) contributes to the pathogenesis of age-related cataract (ARC). The purpose of this research is to underlie the potential mechanism of E3 ligase Parkin and its oxidative stress-associated substrate in cataractogenesis. MethodsThe central anterior capsules were obtained from patients with ARC, Emory mice, and corresponding controls. SRA01/04 cells were exposed to H2O2 combined with cycloheximide (a translational inhibitor), MG-132 (a proteasome inhibitor), chloroquine (an autophagy inhibitor), Mdivi-1 (a mitochondrial division inhibitor), respectively. Co-immunoprecipitation was employed to detect protein-protein interactions and ubiquitin-tagged protein products. Levels of proteins and mRNA were evaluated by western blotting and quantitative RT-PCR assays. ResultsGlutathione-S-transferase P1 (GSTP1) was identified as a novel Parkin substrate. Compared with corresponding controls, GSTP1 was significantly decreased in the anterior lens capsules obtained from human cataracts and Emory mice. Similarly, GSTP1 was declined in H2O2-stimulated SRA01/04 cells. Ectopic expression of GSTP1 mitigated H2O2-induced apoptosis, whereas silencing GSTP1 aggregated apoptosis. In addition, H2O2 stimulation and Parkin overexpression could promote the degradation of GSTP1 through the ubiquitin-proteasome system, autophagy-lysosome pathway, and mitophagy. After co-transfection with Parkin, the non-ubiquitinatable GSTP1 mutant maintained its anti-apoptotic function, while wildtype GSTP1 failed. Mechanistically, GSTP1 might promote mitochondrial fusion through upregulating Mitofusins 1/2 (MFN1/2). ConclusionOxidative stress induces LECs apoptosis via Parkin-regulated degradation of GSTP1, which may provide potential targets for ARC therapy.

Anterior lens capsule: Biological drape.

Small perforations are often managed with cyanoacrylate glue - bandage contact lens (BCL). An additional layer with substances like sterile drape often enhances the strength of the glue. Herein, we describe a novel method of using anterior lens capsule as biological drape to secure perforation. The anterior capsule was secured from femtosecond laser-assisted cataract surgery (FLACS) and placed over the perforation after folding it twice. The area was dried and a small aliquot of cyanoacrylate glue was applied over it. The BCL was applied over it after the glue was dry. In our series of five patients, none of them needed repeat surgery and all cases healed by three months without vascularization. It is a unique technique to secure small corneal perforations.

Selective laser capsulotomy complications: Management and prevention.

To report how to manage and prevent the incomplete laser cut and following uncut tags of anterior capsular lens, performed using the selective laser capsulotomy. We describe three possible approaches: peeling the anterior capsulotomy disc with forceps, breaking the tags using the cystotomy needle tip, or cutting them using a 23-G vitrectomy scissors. Using the 23-G vitrectomy scissors resulted in no complication. Peeling the anterior capsulotomy using the forceps instead caused zonular stress with subsequent risks of zonular dialysis, whereas using the cystotomy needle tip resulted in irregular capsulotomy rim and weakness all along the capsulotomy edge where micro tears caused a tear during the rest of cataract surgery. Incomplete laser cut and subsequent discontinuous capsulotomy results in the presence of multiple tags which create strong adherence between the central capsulotomy disc and the peripheral capsule. Key steps of the procedure to prevent an incomplete laser cut, which are the anterior lens capsule staining and laser beam focusing, and how to correctly manage them, which may shorten the learning curve and enhance the outcomes.

Relationship between expression levels of TDRD7 and CRYBB3 and development of age-related cortico-nuclear cataracts

BackgroundThe human lens develops age-related cataracts (ARCs) because of the complicated effects of aging and stressful conditions. Under conditions involving oxidative stress, cells form stress granules (SGs). TDRD7 has been identified as an RNA granule component and an important component of SGs. TDRD7 plays a role in the post-transcriptional expression of genes, such as the crystallin gene CRYBB3. Therefore, the present study investigated TDRD7 and CRYBB3 mRNA expressions in relation to age-related cortico-nuclear cataracts.MethodsQuantitative real-time PCR was used to determine the expression levels of TDRD7 and CRYBB3 in 52 patients with ARC and 52 healthy controls. Anterior lens capsules and peripheral blood samples from patients with ARC were included in the patient group, and peripheral blood samples from healthy subjects and human lens epithelial cells (HLE-B3) were included in the control group. Gene expression levels in the different age groups were compared. Correlation analysis was used to assess the gene expression levels and age.ResultsThe expression of TDRD7 and CRYBB3 was significantly up-regulated (P < 0.0001) in anterior lens capsules compared to that in HLE-B3 cells. Similarly, the expression of TDRD7 (P = 0.0004) and CRYBB3 (P < 0.0001) was higher in the peripheral blood samples of patients with ARC than in those of healthy subjects. Significant upregulation (P < 0.05) was observed in the 71–81-year age group of patients. No correlation was found between gene expression levels and age.ConclusionSignificantly higher expression levels of TDRD7 and CRYBB3 in patients with ARC than in controls suggest that TDRD7 and CRYBB3 are associated with the development of age-related cortico-nuclear cataracts and the aging process under chronic stress.

Хирургического лечение макулярного разрыва большого диаметра с применением аутокапсулы хрусталика на примере клинического случая

The development of new, more effective methods for closing large macular holes remains an urgent problem in vitreoretinal surgery. Authors proposed a method for the surgical treatment of macular holes when this ophthalmopathology combined with cataract (RU Patent № 2731794), including vitrectomy, removal of posterior hyaloid membrane, imaging macular area within dye, internal limiting membrane peeling, flap formation from anterior lens capsule for macular hole closing during cataract phacoemulsification, flap transplanting to macular hole, followed by tamponade of the vitreal cavity, at first with perfluorocarbon, then replacing it to gas-air mixture. The article presents a clinical case of combined surgical treatment of cataract and large-diameter macular hole according to proposed method, which made it possible to achieve a good and stable morphofunctional result (macular hole closure 6 months after surgery, visual acuity increase to 0.4). Keywords: large-diameter macular hole, cataract, surgical treatment, anterior lens capsule, macular hole closure

The Presence of Pigmentation on Central Anterior Lens Capsule in the Human Leukocyte Antigen B27-Associated Anterior Uveitis and Its Value in Clinical Diagnosis

ABSTRACT Purpose To report on the value of presence of pigmentation on central anterior lens capsule (PioLe) in HLA B27- associated anterior uveitis (HLA B27-AU). Methods 268 patients (320 eyes) with AU were reviewed. Two diagnostic models to predict probability of HLA-B27-AU were developed. The first model included 6 variables (age, gender, unilaterality, presence of non-granulomatous keratic precipitates, hypopyon, and intraocular pressure (IOP). The second model was developed to investigate the added value of PioLe into the first model. Results Unilaterality, presence of hypopyon, IOP <21 mmHg and PioLe were characteristic for HLA-B27 positive patients (P≤0.003 for all). All of 6 variables had area under receiver operating characteristic curves (AuROC) ≤ 60, but PioLe reached even higher value (65.5). Diagnostic model I and II had AuROC 76.3% (95%CI, 68.4%-84.2%) and 80.0% (95%CI, 72.6%-87.5%), respectively. Conclusions Unilaterality, hypopyon, IOP <21 mmHg and presence of PioLe are clinical signs suggesting HLA B27- AU.

Multiple linear regression model for improving accuracy of capsulorhexis size calculation in femtosecond laser-assisted cataract surgery for adults: a retrospective single-center study

BackgroundDifferences between programmed capsulorhexis diameter and actual resulting capsulorhexis diameter (ARCD) are commonly encountered in femtosecond laser-assisted cataract surgery (FLACS). The purpose of this study was to identify the preoperative ophthalmic variables influencing capsulorhexis diameter index (CDI) in FLACS for adults and create a multiple linear regression model for obtaining a more accurate capsulorhexis diameter.MethodsThis retrospective study involved sixty-seven eyes of 44 patients who received FLACS and intraocular lens implantation. The ARCD was measured using anterior segment swept-source optical coherence tomography (CASIA 2). Keratometry (K1, K2 and average K), anterior chamber depth (ACD), lens thickness (LT), anterior chamber width (ACW), white-to-white (WTW), curvature radius of anterior lens capsule (Front R) and axial length (AL) were all measured preoperatively. Based on the derived data, LT/ACW, LT/AL, LT/ACD and LT/ACW/Front R were calculated. The ratio of the programmed capsulorhexis diameter and ARCD was defined as the CDI. Correlation analysis was conducted to examine the relationship between preoperative variables listed above and the CDI. Multiple linear regression analysis was applied to select the most influential preoperative variables on CDI.ResultsACD, LT, ACW, Front R, AL, LT/ACW, LT/AL, LT/ACD, and LT/ACW/Front R showed significant correlation with CDI. Front R and LT/ACW/Front R were selected as constants in the multiple linear regression model using stepwise variable selection. The following equation represents the multiple linear regression model: CDI = 1.306–4.516 × LT/ACW/FrontR-0.011 × Front R, when P < 0.0001, adjusted R-squared = 0.919, variance inflation factor = 8.389, and Durbin-Watson ratio = 1.846.Predicted postoperative capsulorhexis diameter (PPCD) equation was created based on CDI equation as follows: PPCD = programmed capsulorhexis diameter × 1.306–4.516 × LT/ACW/FrontR-0.011 × Front R.ConclusionFront R and LT/ACW/Front R were found to be the most significant influencing factors of capsulorhexis size. CDI and PPCD calculation equations presented in this study may be useful in setting up more accurate programmed capsulorhexis diameter for FLACS in adults, resulting in a precise ARCD.

Upregulation of histone H3 caused by CRYAA may contribute to the development of age-related cataract

Objective: Age-relate cataract (ARC) is a disease of the eyes with no effective drugs to prevent or treat patients. The aim of the present study is to determine whether histone H3, αA-crystallin (CRYAA), β-galactosidase (GLB1), and p53 are involved in the pathogenesis of ARC. Methods: A total of 99 anterior lens capsules (ALCs) of patients with ARC of various nuclear grades, ultraviolet models of ALCs, and two human lens epithelial cell lines (FHL-124 and SRA01/04) were used, and the expression of histone H3, CRYAA, GLB1, and p53 were detected by immunoblotting and reverse transcription and real time-quantitative polymerase chain reaction. The association between CRYAA with histone H3, GLB1, and p53 was assessed in FHL-124 and SRA01/04 cells following CRYAA overexpression. Results: Histone H3 and p53 in ALCs of patients with ARC were up-regulated in a grade-dependent manner, and the expression of CRYAA showed a positive association with histone H3, p53, and GLB1. In UV models of ALCs and human lens epithelial cell lines, the expression levels of histone H3, cell apoptosis factors (Bax/Bcl-2, cleaved caspase-3), and inflammation factors (interleukin-6, tumor necrosis factor-α) were all up-regulated. Furthermore, transfection of CRYAA in FHL-124 cells induced overexpression of histone H3. Conclusion: CRYAA-mediated upregulation of histone H3 may be involved in the pathogenesis of ARC. p53 may also have a role in ARC development, but not via the CRYAA-histone H3 axis. The results of the present study may assist in improving our understanding of the pathogenesis of ARC and in identifying potential targets for treatment.

The Perioperative Profile of Community Outreach Camp Patients with Pseudoexfoliation Who Underwent Cataract Surgery in a Tertiary Care Centre

Purpose: To study the perioperative profile of pseudoexfoliation (PXF) among the camp patients who underwent cataract surgery. Methods: This retrospective study was conducted among camp patients with PXF, who underwent cataract surgery in a tertiary care centre. Anterior segment examination including distribution of PXF material over anterior segment structures, pupillary dilatation, gonioscopy, applanation tonometry, intraoperative and postoperative complications, and subsequent management were all documented from the records. Results: A total of 1985 patients underwent cataract surgery between November 2016 and October 2019 of which PXF was recorded in 140 (7%) patients. 49 patients had bilateral PXF, while 83 patients had unilateral PXF. 50% (91/181) of eyes had PXF on anterior lens capsule and pupillary border and 67% (113/167) of eyes had both cortical and nuclear cataracts simultaneously. Intraocular pressure (IOP) was significantly elevated in PXF eye of unilateral PXF patients. The prevalence of PXF glaucoma in our study population was 2.8%. 16.7% (22/132) of patients had intraoperative complications of which posterior capsule rent (PCR) occurred more in bilateral PXF patients and zonular dehiscence (ZD) was seen more in unilateral PXF patients. Postoperatively, surge in anterior segment inflammation was noted from 8% on the first day to 11% at the end of the first week. Conclusions: PXF eyes require meticulous preoperative examinations and intraoperative handling to prevent complications like ZD and PCR. Following cataract surgery, these patients require frequent follow-up visits in the initial two weeks of postoperative period to address the surge in anterior chamber reactions.

Capsule-epithelium-fibre unit ultrastructure in the human lens.

This study aimed to investigate the capsule-epithelium-fibre unit ultrastructure of the human lens, particularly the interfaces of the epithelium with the capsule and the epithelium with the fibre cell. A total of 12 lenses from donor humans who died of trauma without systemic and ocular diseases were investigated by transmission electron microscopy (TEM), combined with immunofluorescence staining for localising certain specific proteins. Some of the results were further studied in the anterior lens capsules of cataract patients. Our results revealed capsule protrusion into the epithelium in some areas and potential processing of capsule components. The young elongating fibre cells directly adjacent to the epithelium with a high stain density strongly expressed CD24. Numerous extracellular vesicles could be seen in the space between human lens epithelial cells (HLECs) and between HLECs and the capsule. Mitophagy and autophagy were also observed in the HLECs. Our research may be beneficial in better understanding the function of the human lens.

Ex vivo evaluation of anterior lens capsule staining in horses with three concentrations of gentian violet for surgical training

Resumo O objetivo deste estudo foi avaliar e comparar a eficácia de três concentrações de violeta genciana (0,5%, 0,1% e 0,05%) na coloração da cápsula anterior da lente em equinos. Trinta e seis olhos de equinos post-morten foram utilizados. De acordo com a concentração de violeta genciana utilizada, os olhos foram subdivididos em três grupos compostos por 12 olhos cada. A avaliação da eficácia em coloração da cápsula anterior da lente com diferentes concentrações de violeta de genciana foi realizada por meio de um sistema empírico de avaliação da coloração adequada ou inadequada de retalhos capsulares. Com base na avaliação dos examinadores, as concentrações de 0,1% e 0,05% de violeta de genciana permitiram a visualização adequada da cápsula anterior para o treinamento da capsulotomia curvilínea contínua enquanto a concentração de 0,5% produziu uma coloração capsular forte e inadequada. O modelo desenvolvido com violeta genciana, nas concentrações de 0,1% e 0,05%, permitiu a visualização nítida do retalho capsular, o que o torna viável como modelo para treinamento da etapa de capsulotomia curvilínea contínua em cirurgia de catarata em equinos.