Anterior Lens Capsule Research Articles

Current possibilities of laser surgery on anterior eye segment

The article summarizes the experience of recent years in the development and implementation of novel original laser technologies used in surgery of the anterior segment of the eye. The presented technology of laser activation of scleral hydropermeability (LASH) in glaucoma is based on the effect of enhanced transscleral filtration and has been shown as effective and safe, which was confirmed by the results of a comprehensive clinical and experimental study. Development of another technique was associated with the need to improve the safety of laser interventions in anterior capsule contraction syndrome in pseudophakia, and resulted in a proposition to change the configuration of the anterior lens capsule incision from the usual linear-radial to T-shaped laser anterior capsulorhexis. The proposed technology of laser photomydriasis based on near-infrared radiation of the diode laser (0.810 μm) has shown its effectiveness and gentle nature (absence of atrophy of the iris stroma and post-burn pigmentation) in ectopias and pupil deformity.

Клиническое наблюдение больного после комбинированного хирургического лечения макулярного разрыва большого размера при осложненной катаракте

The only effective treatment for macular holes (MH) is surgery. Published data demonstrate that surgery (vitrectomy, internal limiting membrane/ILM peeling, and vitreous tamponade) of small and medium MHs is usually highly effective. Meanwhile, good outcomes and a high recurrence rate of large MHs postoperatively remain challenges. The authors propose a surgical technique for MHs in complicated cataracts (patent of the RF No. 2731794 dated 09/08/2020) that involves vitrectomy, posterior hyaloid removal, ILM staining, ILM peeling, formation of a flap from the anterior lens capsule to close MH, and air tamponade. This paper describes a woman who underwent combined surgery for cataract and MH as described. The technique provided a complete and stable anatomical outcome. After 1 month (i.e., after complete resorption of air), the best-corrected visual acuity of the right eye increased to 20/40. IOP was 19.0 mm Hg. KEYWORDS: vision, idiopathic macular hole, retina, anterior les capsule, surgery, postoperative follow-up. FOR CITATION: Bikbov M.M., Orenburkina O.I., Zinnatullin A.A., Yarmukhametova A.L., Babushkin A.E., Kalanov M.R. Combined surgery for large macular hole in complicated cataract: case report. Russian Journal of Clinical Ophthalmology. 2023;23(3):152–156 (in Russ.). DOI: 10.32364/2311-7729-2023-23-3-7.

Complications and visual outcome of cataract surgery in pseudoexfoliation patients

Pseudoexfoliation syndrome is a multifactorial diffuse disease and is diagnosed clinically on slit lamp examination of the eye by the deposition of white, dandruff like material on different structures in anterior segment i:e corneal endothelium, iris, pupillary margin, anterior lens capsule, zonules and trabecular meshwork. The aim of study was to study demographic features, intraoperative and postoperative complications and the visual outcome of cataract surgery in pseudoexfoliation patients. 93 eyes of 93 patients with pseudoexfoliation posted for cataract surgery were included in the study. 79.56% patients were of more than 60 years of age group.43 patients were male and 50 patients were female. 44 patients had pseudoexfoliation syndrome in both eyes and 49 patients had either right eye or left eye involvement. Intraoperative problems encountered were poor pupillary dilatation, capsular bag prolapse, zonular dehiscence, posterior capsular rent, residual cortical matter and positive vitreous pressure. Postoperative complications reported were corneal edema, raised intraocular pressure, significant anterior chamber cell reaction, left cortical matter and exudative membrane. Best corrected visual acuity was more than 6/18 in 67 eyes, between 6/60-6/24 in 16 eyes, and less than 6/60 in 10 eyes. At 1 month, best corrected visual acuity was more than 6/18 in 92 eyes. Cataract surgery in pseudoexfoliation patients is associated with high risk of complications. Use of iris hooks and capsule tension rings where required during the surgery can decrease the intraoperative complications and thus will give better visual outcome.

ОПТИМИЗАЦИЯ ЭНЕРГЕТИЧЕСКИХ ПАРАМЕТРОВ ФЕМТОЛАЗЕРНОЙ ПЕРЕДНЕЙ КАПСУЛОТОМИИ В ХИРУРГИИ НАБУХАЮЩИХ ПЕРЕЗРЕЛЫХ КАТАРАКТ

The study included 40 patients (40 eyes) with swellingovermature cataract. These patients were divided into groups. The first group included 10 patients (10 eyes) with fibrotic changes in the anterior lens capsule, where the power offemtolaser energy exposure during anterior femtocapsulotomy was 100 %. The second group consisted of 10 patients (10 eyes) with thinning of the anterior lens capsule, where the power of femtolaser energy exposure was 60 %. The third and fourth groups were controls, 10 patients each (10 eyes) with fibrotic changes and thinning of the anterior capsule, respectively, where the power of femtolaser energy exposure was 80% (recommended by the manufacturer of the laser unit). In the first and second groups, in contrast to the control, the absence of tissue bridges was achieved in almostall cases.The carved disc stood out freely, without additional traction, leaving no burrs. These burrs cause radialization of the anterior capsule during manipulation during cataract surgery.As a result of the study, the optimal values of the power of femtolaser exposure were selected for anterior femtocapsulotomy in case of detection of fibrosis or thinning of the anterior lens capsule in case of swelling overmature cataract.

Novel clinical presentation and PAX6 mutation in families with congenital aniridia.

To explore the clinical phenotype and genetic defects of families with congenital aniridia. Four Chinese families with aniridia were enrolled in this study. The detailed ocular presentations of the patients were recorded. Whole exome sequencing (BGI MGIEasy V4 chip) was used to detect the gene mutation. Sanger sequencing was performed to validate the potential pathogenic variants, and segregation analysis was performed on all available family members. By whole exome sequencing and Sanger sequencing, three recurrent mutations (c.112del, p.Arg38Glyfs*16; c.299G > A, p.Trp100* and c.718C > T, p.Arg240*) and one novel mutation (c.278_281del, p.Glu93Alafs*30) of PAX6 were identified. All the mutations were co-segregated with the phenotype in the families. We also observed spontaneous anterior lens capsule rupture in aniridia for the first time. We report spontaneous anterior lens capsule rupture as a novel phenotype of aniridia and three recurrent mutations and one novel mutation of PAX6 in families with aniridia. Our results expanded the phenotype and genotype spectra of aniridia and can help us better understand the disease.

Histopathological findings of anterior lens capsule in paediatric cataract patients

AbstractPurpose: To investigate the histopathological findings of the anterior lens capsule in patients with paediatric cataracts.Methods: This study is a prospective interventional study. Anterior capsule tissue samples which were obtained by anterior capsulotomy method during phaco surgery were fixed in 0.1 M phosphate buffered 2.5% glutaraldehyde at +4°C for 2–4 h and after passing through other stages, thin sections were taken and stained. It was then examined and visualized under HITACHI HT7800 transmission electron microscope.Results: Twenty‐three eyes of 19 patients were included. Three patients had unilateral cataract and remaining 16 had bilateral cataract. Four patients had concomitant systemic disease including hydrocephalus, cerebral palsy, juvenile myelomonocytic leukaemia and Down syndrome. Except for one patient, common findings were single‐layered epithelium under the capsule, degenerated organelles with round‐oval and prismatic‐oval nuclei in some regions, enlarged mitochondria and heterochromatin cells. In the case with cerebral palsy, unlike the normal lens structure, collagen fibrils of the connective tissue and fibroblast‐like cells were observed in the epithelial area that should be located under the capsule, in both eyes. Disorganized distribution of collagen fibrils and vacuole structures in the cytoplasm of fibroblast‐like cells were observed.Conclusions: Similar histopathological findings were found in paediatric cataracts with or without systemic disease. Due to the presence of increased inflammation and gliosis in cerebral palsy, the absence of lens epithelium may have developed as a result of degeneration in this patient. The absence of lens epithelium and inflammation are thought to play a role in the development of dense subcapsular fibrosis.

Exosomal microRNA-222-3p increases UVB sensitivity of lens epithelium cells by suppressing MGMT.

Age-related cataract (ARC) is a leading cause of blindness worldwide with multiple pathogenic factors. Oxidative damage of lens epithelium cells (LECs) is one of the well-accepted pathogenesis of ARC which can be regulated by DNA repair genes (DRGs). The present research aimed to clarify the regulatory mechanism of exosomal microRNAs (miRNAs) on DRGs in LECs. The LECs oxidative damage model was established by UVB-irradiation on SRA01/04 (human lens epithelium cell line). Exosomes from UVB-irradiated cells (UVB-exo) and exosomes from normal control cells (NC-exo) were collected from the culture medium. To explore the functions of LECs exosomes, SRA01/04 were incubated with UVB-exo/NC-exo. Then, we detected SRA01/04 proliferation, viability and apoptosis respectively using 5'-ethynyl-2'-deoxyuridine(EdU), cell-counting kit-8(CCK-8) and TdT-mediated dUTP Nick-End Labeling(TUNEL) assay. Next, the miRNA expression profiles of UVB-exo and NC-exo were identified by miRNA microarrays. RNA expression in exosomes, cells, and clinical samples was verified by qRT-PCR. The location and expression of MGMT and CD63 proteins were detected by immunofluorescence and western blot. The 3'UTR regulation of miR-222-3p to MGMT was verified by luciferase analyses. MGMT down-regulated while miR-222-3p up-regulated in LECs sub-central anterior capsule from ARC lenses. MGMT and miR-222-3p expressions in central and peripheral LECs from anterior lens capsules were differential. UVB-exo can transport the up-regulated miR-222-3p from oxidative-damaged LECs to normal LECs, which could suppress MGMT expression and increase UVB sensitivity of LECs. Findings on exosomal miRNA functions provided novel insights into pathogenesis of ARC. Exosomal miR-222-3p can be a potential target for prevention and cure of ARC.

Prevalence of Pseudoexfoliation Among Adults and Its Related Ophthalmic Variables in Southern Ethiopia: A Cross-Sectional Study.

A community-based study was conducted to determine the prevalence and sociodemographic factors of pseudoexfoliation syndrome among adults in Southern Ethiopia. A community-based cross-sectional study was conducted among subjects aged 40 years or older. Subjects underwent standardized examination, including portable slit-lamp biomicroscopy before and after pupillary dilatation, and intraocular pressure measurement using Tono-Pen. Pseudoexfoliation was diagnosed on slit-lamp examination by the presence of white dandruff-like material on the pupillary margin and/or on the anterior lens capsule of one or both eyes. Among 760 participants, the prevalence of pseudoexfoliation was 12.0% (95% confidence interval: 9.7-14.3%). The mean age of pseudoexfoliation cases was 63.9 years (SD 9.96, age range 40-90 years). The prevalence increased with increasing age, with 26.9% of those 60 or older affected. Slightly higher proportion of males (12.4%) were found to have pseudoexfoliation in either of the eyes than females (11.6%) which was not statistically significant (p = 0.738). Mean IOP in subjects with pseudoexfoliation was found to be 20.65 ± 5.15 mmHg, while it was 15.0 ± 2.3 mmHg for those without pseudoexfoliation. The difference between the two populations was found to be statistically significant (P < 0.05). The prevalence of pseudoexfoliation in eyes of people in Southern Ethiopia appears greater than that reported in other places of Africa and Asia. Pseudoexfoliation occurs at a relatively younger age in our population. Increasing age is associated with the presence of pseudoexfoliation, and pseudoexfoliation in turn is associated with higher intraocular pressure.

The Importance of MicroRNA Expression in Pseudoexfoliation Syndrome.

Pseudoexfoliation syndrome (PEX) is an important systemic disorder of the extracellular matrix, in which granular amyloid-like protein fibers accumulate in the anterior segment of the eyeball as well as in other organs. PEX is currently considered to be a multifactorial systemic disorder with genetic and environmental risk factors. The aim of this manuscript was to analyze miR expression in PEX. In recent years, an attempt has been made to investigate and describe the level of expression of selected miRs in PEX. Four polymorphisms of genes isolated from the blood that may be related to PEX were identified and miR-122-5p was found to be upregulated in patient blood. Furthermore, 18 miRs were identified with a statistically different expression in the aqueous humor. A significantly elevated expression of miR-125b was found in the anterior lens capsule, and four miRs were described, which may have a significant impact on the development of PEX. Regulatory miR molecules are gaining more and more importance in research aimed at identifying and isolating molecular markers related to the pathogenesis and prognosis of PEX, but further studies are needed.

Towards preventing exfoliation glaucoma by targeting and removing fibrillar aggregates associated with exfoliation syndrome

Exfoliation syndrome presents as an accumulation of insoluble fibrillar aggregates that commonly correlates with age and causes ocular complications, most notably open-angle glaucoma. Despite advances in understanding the pathogenesis and risk factors associated with exfoliation syndrome, there has been no significant progress in curative pharmacotherapy of this disease. It is thought that the ability to target the fibrillar aggregates associated with exfoliation may offer a new therapeutic approach, facilitating their direct removal from affected tissues. Phage display techniques yielded two peptides (LPSYNLHPHVPP, IPLLNPGSMQLS) that could differentiate between exfoliative and non-affected regions of the human lens capsule. These peptides were conjugated to magnetic particles using click chemistry to investigate their ability in targeting and removing exfoliation materials from the anterior human lens capsule. The behavior of the fibrillar materials upon binding to these magnetic particles was assessed using magnetic pins and rotating magnetic fields of various strengths. Ex vivo studies showed that the magnetic particle-peptide conjugates could generate enough mechanical force to remove large aggregates of exfoliation materials from the lens capsule when exposed to a low-frequency rotating magnetic field (5000 G, 20 Hz). Biocompatibility of targeting peptides with and without conjugated magnetic particles was confirmed using MTT cell toxicity assay, live/dead cell viability assay, and DNA fragmentation studies on primary cultured human trabecular meshwork cells. This is a novel, minimally invasive, therapeutic approach for the treatment of exfoliation glaucoma via the targeting and removal of exfoliation materials that could be applied to all tissues within the anterior segment of the eye.

Paired Box Gene 6 Regulates Heme Oxygenase-1 Expression and Mitigates Hydrogen Peroxide-Induced Oxidative Stress in Lens Epithelial Cells

Purpose This study aimed to investigate the regulation of heme oxygenase-1 (HO-1) by paired box gene 6 (Pax6) and their roles in hydrogen peroxide (H2O2)-induced oxidative stress and apoptosis in lens epithelial cells (LECs) (SRA01/04, HLE-B3). Methods Lens anterior capsule membranes of mice of different ages were obtained to compare differences in the expression of Pax6 and HO-1 using Western blotting. Pax6-overexpressing plasmid and small interfering RNA were designed to overexpress and silence Pax6, respectively. Cobalt protoporphyrin (CoPP) was used to promote the expression of HO-1. Oxidative damage in LECs was induced by treatment with H2O2 (400 µM) for 24 h. Cell viability was measured using the Cell Counting Kit-8 assay. Intracellular reactive oxygen species (ROS) were detected using flow cytometry and immunofluorescence. Superoxide dismutase (SOD) level was measured using SOD Assay Kit and apoptotic cells were quantified using annexin V-fluorescein isothiocyanate/propidium iodide staining. Results Pax6 and HO-1 expression levels showed an age-dependent decrease in LECs of mouse. Overexpressing Pax6 upregulated HO-1 expression level. Silencing Pax6 downregulated the HO-1 expression level, resulting in increased generation of ROS, reduced SOD activity, decreased cell viability, and increased apoptotic cells of LECs under H2O2-induced oxidative stress. Overexpressing Pax6 and CoPP both mitigates H2O2-induced oxidative stress by increasing the expression of HO-1 of LECs. Conclusion Pax6 and HO-1 expression levels showed an age-dependent decrease in LECs in mouse anterior capsules. Pax6 could regulate the expression of HO-1 in LECs. The decrease of Pax6 weakened the antioxidant ability of LECs under H2O2-induced oxidative stress by downregulating HO-1, which may be a potential mechanism for the formation of age-related cataract.

Inside-out and outside-in: Tips and tricks in posterior lenticonus.

Posterior lenticonus is a congenital condition characterized by the thinning and bowing of posterior lenticular capsule. Cataract develops when normal intra-lenticular pressure bulges the posterior capsule at the circumscribed portion of inherent thin posterior lens capsule, leading to derangement of lamellar lens fibers. This condition poses a surgical challenge as the presentation varies from thin, bulging posterior capsule to large, pre-existing posterior capsular dehiscence. This video highlights the tips for the surgical management of various scenarios of posterior lenticonus. In this video, tips for surgical management of various scenarios of posterior lenticonus are illustrated. Intraoperatively, ruptured posterior capsule is suspected by the presence of a fish-tail sign. The anterior capsulotomy is relatively easier in a flatter anterior lens capsule, owing to reduced intra-lenticular pressure. Hydro-dissection is avoided to prevent extension of pre-existing posterior capsular dehiscence or creation of rupture in a thinned-out capsule. The peripheral lens cortex aspiration is initiated first, followed by in each quadrant. In a presence of ruptured posterior capsule by vigilant inspection at this stage, the surgeon should change the direction of lens matter aspiration by aspirating the central lenticular matter first, followed by peripheral cortex like "inside-out". In absence of posterior capsule dehiscence, peripheral cortex is aspirated first, followed by central lens matter aspiration like "outside-in". Adequate anterior vitrectomy is performed until there are no vitreous tags. In the presence of pre-existing posterior capsular defect, the lens matter is aspirated from the center (inside-out), whereas in the absence of capsular defect, the lens matter is aspirated from the periphery (outside-in). https://youtu.be/8G6BCbFwr8Q.

A Novel Cost-Effective Simulation Model for Continuous Curvilinear Capsulorhexis.

IntroductionWe describe and validate a low-cost simulation model for practicing anterior lens capsule continuous curvilinear capsulorhexis (CCC).MethodsA simulation model for CCC was developed from widely available low-cost materials. Ophthalmologists attending the annual scientific meeting of the Research Institute of Ophthalmology, Giza, Egypt, were asked to perform a five CCC model task and then anonymously answer a questionnaire that assessed the realism and training utility of the model using a five-point Likert scale (1 = unacceptable, 2 = poor, 3 = acceptable, 4 = favorable and 5 = excellent).ResultsTwenty-seven ophthalmologists completed the task and the anonymous questionnaire. Overall, participants felt that the model simulated CCC step in cataract surgery well (mean: 3.5) and was comparable to other kinds of CCC simulation models (mean: 3.3). The model scored highly for its overall educational value (mean: 4.00) and for enlarging a small CCC (mean:3.7), while the feasibility of this model in practicing the management of a runaway leading edge of CCC scored 2.9.ConclusionThis model may provide an alternative method for training for CCC and other anterior lens capsule-related maneuvers. This option may be particularly helpful for residency training programs with limited access to virtual reality simulators or commercially available synthetic eye models.

Unilateral advanced glaucoma in isolated congenital ectropion uveae with ipsilateral ptosis: A pictorial description of five children.

Aim: To report the cases of five children with unilateral advanced glaucoma in isolated congenital ectropion uveae (CEU) with ipsilateral ptosis and myopia. Methods: This is an ambispective observational case series. After diagnosing one patient with CEU and glaucoma, consecutive patients presenting with unilateral ptosis, congenital iris anomaly, and glaucoma between 2014 to 2020, and had completed a minimum one-year postoperative follow-up, were analyzed. Results: Of the 1421 newly registered pediatric glaucoma patients in the period under review, five children were diagnosed with CEU. All patients presented with gradual painless diminution of vision in the left eye in early adolescence. The left eye of all patients had peculiar clinical features: mild congenital ptosis, high iris insertion, crypt-less smooth iris surface, congenital ectropion uveae, pigments over anterior lens capsule, high myopia, advanced glaucomatous optic disc cupping, and very high intraocular pressure (IOP), which was > 45 mmHg in all cases. The right eye showed signs of angle dysgenesis with mild anterior iris insertion and numerous fine iris processes. Antiglaucoma medications and angle surgery failed to control the IOP, and all children required glaucoma filtration surgery, resulting in reasonable IOP control. Despite the older age, postoperative strict amblyopia treatment resulted in significant improvement in vision.Conclusions: Although ectropion uveae and ptosis have been present since birth, unilaterality, and the asymptomatic nature of the disease led to the late presentation with irreversible damage. Early surgical management and amblyopia therapy are the cornerstones of management.Abbreviations: CEU = Congenital ectropion uvea, CIES = Congenital Iris Ectropion Syndrome, ASD = Anterior segment dysgenesis syndrome, BCVA = Best-corrected visual acuity, IOP = Intraocular pressure

Firecracker Cataract

A healthy 5-year-old boy was brought to our clinic with decreased vision in both eyes (OU). His best-corrected visual acuity was 20/200 OU. Slit-lamp examination revealed developmental cataract OU, in the form of multiple glistening sparks and lines originating from the center of the anterior capsule of lens, resembling a firecracker illuminating the sky (Fig A, B). His family history was unremarkable, and there was no history of trauma. The child underwent sequential cataract aspiration with intraocular lens implantation OU, with postoperative visual acuity of 20/40 OU.

A Study of Difficulties and Complications Encountered in Patients with Pseudoexfoliation Syndrome Undergoing Manual Small Incision Cataract Surgery (MSICS)

Pseudoexfoliation syndrome (PEX) is a systemic age-related disorder that is characterised by abnormal production of fibrillar extracellular matrix material and it's deposition in tissues of the eye and other systemic tissues. They are classically seen as deposits on the anterior lens capsule as dandruff-like white powdery residue. The material deposits in all anterior segment structures including iris, pupillary margins, ciliary body, corneal endothelium, zonules and anterior capsule of lens. In the eye, these deposits cause deviancy from normal structure and function, resulting in poor pupil dilatation, zonular weakness, changes in corneal endothelium, secondary glaucoma and nuclear cataract formation. These changes caused in the eye due to Pseudoexfoliation Syndrome can be a challenge for a surgeon doing routine cataract extraction and intraocular lens implantation in such patients, as these manifestations of PEX can prove to be obstacles during the surgery and cause post operative complications. The surgeon also has to keep in mind associated secondary glaucoma during management of such a case. Thus visual outcome could be compromised.

REPS2 downregulation facilitates FGF-induced adhesion and migration in human lens epithelial cells through FAK/Cdc42 signaling and contributes to posterior capsule opacification

Posterior capsular opacification (PCO) can cause postoperative visual loss after cataract surgery. Residual human lens epithelial cell (HLEC) proliferation, migration, epithelial-mesenchymal transition (EMT) and synthesis of extracellular matrix (ECM) are the entitative reasons for PCO. Low expression of Ral-binding protein 1-associated Eps domain-containing 2 (REPS2) and high levels of basic fibroblast growth factor (b-FGF) were observed in the lens and postoperative aqueous humor of cataract patients. REPS2 was identified as a negative regulator in growth factor signaling; however, its function in HLECs is unknown. This was first investigated in the present study by evaluating REPS2 expression in anterior lens capsules from cataract patients, a mouse cataract model, and HLE-b3 cells. The biological function of REPS2 in HLE-B3 cells was assessed by REPS2 silencing and Cell Counting Kit 8, wound healing, Transwell migration, F-actin staining, G-protein pulldown and western blot assays. In the present study, REPS2 was significantly downregulated in human and mouse cataract capsules and H2O2-treated HLE-B3 cells. REPS2 knockdown increased fibronectin, type I collagen, and α-smooth muscle actin expression levels and stimulated HLECs proliferation and migration; these effects were enhanced by FGF treatment and accompanied with focal adhesion kinase (FAK) phosphorylation, cell division cycle 42 (Cdc42) activation, focal adhesion protein upregulation, and F-actin cytoskeleton reorganization. However, treatment with the FAK inhibitor PF573228 abolished these effects. Thus, REPS2 downregulation in cataract HLECs induces their proliferation and facilitates FGF-induced ECM synthesis, EMT, cell adhesion and migration by activating FAK/Cdc42 signaling, which may underlie PCO pathogenesis.

Comparison of the biometric parameters in patients with high myopia and anisometropia

BackgroundTo compare biometric parameters, especially lens parameters, in patients with high myopia and anisometropia.MethodsPatients with spherical equivalent greater than -6D and at least one eye with an axial length greater than 26 mm and a difference in binocular axial length greater than 2 mm were included in this study. In each patient, the eye with a relatively shorter axial length was assigned to Group S, and the other eye was assigned to Group L. In patients whose binocular axial length difference was greater than 4 mm, the eye with the shorter axial length was assigned to Group S1 and the other eye was assigned to Group L1. In patients whose shorter eye axial was less than 26 mm, the eye with the shorter axial was assigned to Group S2 and the other eye was assigned to Group L2. Central corneal thickness, corneal curvature radius, axial length, anterior chamber depth, lens thickness, white-to-white corneal diameter and the radius of the anterior and posterior lens capsules were compared between Group S and Group L, Groups S1 and L1, and Groups S2 and L2.ResultsSixty-four people were enrolled in the study. There were 26 people with an axial length difference more than 4 mm (Group S1 and Group L1) and 34 patients with an axial length less than 26 mm (Group S2 and Group L2). No significant differences were found in any parameters except axial length between Group S and Group L, Groups S1 and L1, or Groups S2 and L2 (p > 0.05).ConclusionsThe anterior parameters of patients with high myopia did not change with the axial length.

Spontaneaous dislocation of the crystalline lens in the anterior chamber in a patient with pseudoexfoliation syndrome

Pseudoexfoliation syndrome (PEX) is a systemic disorder of the extracellular matrix that presents primarily via its characteristic ocular manifestations [1]. Typically, white fibrillary residue on the anterior lens capsule and pupillary margin is observed, as are pupillary transillumination defects and pigmentation of the trabecular meshwork [2]. Zonular weakness can be attributed to the deposition of pseudoexfoliative material on the zonular fibers and ciliary processes, resulting in a proteolytic disintegration of the zonule that can lead to spontaneous fragmentation [2]. We report a case of a dislocation of the hole crystalline lens in the anterior chamber in a patient with pseudoexfoliation syndrome.

Pyroptosis of lens epithelial cells in diabetic cataract

Objective: To investigate the possible role of pyroptosis of lens epithelial cells (LECs) in the occurrence of diabetic cataract. Methods: Experimental research. A total of 70 cataract lens anterior capsule and aqueous humor samples were obtained from 70 eyes (70 patients) with cataracts in the operation room of Tianjin Medical University Eye Hospital between March 2020 and November 2020. Patients were divided into the non-diabetic and diabetic groups, with 35 patients (35 eyes) in each group. The expressions of Nod like receptor protein 3 (NLRP3), cysteine-aspartic proteases 1 (caspase-1) and Gasdermin D protein (GSDMD) in the lens anterior capsule were detected by Western blotting, real-time quantitative PCR and immunohistochemical staining. Interleukin (IL)-1β and IL-18 inaqueous humor were detected by enzyme-linked immunosorbent assay (ELISA). The independent sample t-test was used for statistical analysis. Results: The age was (70±9) years in the diabetic group and (71±8) years in the non-diabetic group. There was no significant difference in age and gender distribution between the two groups (both P>0.05). Western blotting analysis showed that the expression levels of NLRP3, caspase-1 and GSDMD protein in the LECs of anterior capsule were 1.11±0.06, 0.95±0.04 and 0.39±0.03 in the diabetic group, significantly higher than those of the non-diabetic group (0.81±0.04, 0.33±0.11 and 0.16±0.04; t=4.38, 5.36, 4.63; all P<0.05). Real-time quantitative PCR showed that the levels of NLRP3, caspase-1 and GSDMD mRNA in the LECs of anterior capsule were 1.98±0.07, 54.36±4.88 and 6.98±1.18 in the diabetic group, significantly higher than those of the non-diabetic group (1.38±0.16, 15.31±1.51 and 2.41±0.95; t=3.49, 7.64, 3.00, all P<0.05). Immunohistochemical staining showed that the average gray values of NLRP3, caspase-1 and GSDMD in the diabetic group were higher than those of the non-diabetic group (all P˂0.01). ELISA showed that the levels of IL-1β and IL-18 in the aqueous humor were (4.178±0.028) fg/L and (20.983±0.018) fg/L in the diabetic group, significantly higher than those of the non-diabetic group [(4.063±0.017) fg/L and (20.509±0.073) fg/L; t=20.63, 37.21; both P˂0.01]. Conclusion: Caspase-1-mediated pyroptosis of LECs and the release of inflammatory mediators induced by pyroptosis may be involved in the occurrence and development of diabetic cataract.