Nuclear Opacity Research Articles

Clinical Classification and Management Outcomes of Anterior Segment Dominated Persistent Fetal Vasculature: the CCPMOH report.

To describe clinical features, management, and outcomes of anterior segment dominated persistent fetal vasculature (aPFV) . A secondary analysis of aPFV data from a longitudinal cohort study. The age and gender of each participant upon initial presentation, along with biological parameters, best-corrected visual acuity (BCVA), and biomicroscopic assessments were collected. The aPFV eyes were categorized into 3 groups (type I:pupillary-iris-anterior lens plane, type II:retrolental-anterior hyaloid membrane plane and type III:combined) according to the location of the vascular abnormalities and further classified into mild (a) and severe (b) according to the degree of severity. The surgical techniques used in this investigation were reported. Visual outcomes, ocular hypertension, postoperative adverse events, and additional surgical interventions were recorded at each follow-up visit. A total of 470 individuals (619 eyes) were enrolled (ages 36.7±45.4 months, range 1 to 394 months), divided into 129 eyes (20.8%) Type 1, 420 eyes (67.9%) Type 2, and 70 eyes (11.3%) Type 3. Cataracts were identified in 505 eyes (81.6 %): for type I, the common forms were nuclear and membranous opacity (both 12/50 eyes, 24%); type II: subcapsular opacity (214/399 eyes, 53.6%) and type III: complete cortex (17/56 eyes, 30.4%). Posterior capsular tear was mostly present in type II a. Type III had the shallowest anterior chamber depth and the largest corneal astigmatism. Six hundred patients (96.7%) had surgery. After surgery, 119 eyes experienced adverse events: intravitreal hemorrhages occurred in 0.2% of eyes, visual axis obscuration occurred in 9.4% of eyes, and ocular hypertension which required eye drop medication occurred in 19.2% of eyes. In 47 patients (7.6%), a second surgery procedure was done. In 456 eyes (73.7%), visual acuity had improved at the last follow-up. The worst BCVA was associated with types IIb and IIIb. The magnitude of aPFV can be usefully characterized by a classification protocol focusing on the location and disease severity. Here, we propose a surgical and medical management algorithm for aPFV to achieve favorable outcomes with limited intraoperative and postoperative complications.

Features of hematological indices in cataract in the dynamics of surgical treatment

BACKGROUND: Cataract is one of the most common ophthalmologic diseases leading to blindness. AIM: To study the features of hematological indices in men over 40 years old with different types of cataract before and after surgical treatment. MATERIAL AND METHODS: The examination groups included 25 patients (25 eyes) with opacities localized in the cortical substance of the lens, 19 (19 eyes) with total opacities, 26 (26 eyes) with nuclear opacities, 30 (30 eyes) with subcapsular opacities; of these, 43 patients (43 eyes) had initial cataract, 39 (39 eyes) — immature, 18 (18 eyes) — mature cataract. The control group consisted of 30 people. All study participants underwent a complete ophthalmologic examination and assessment of hematological indices. The following integral hematological indices were calculated using generally accepted formulas: lymphocyte index (lymphocytes/neutrophils); leukocyte intoxication index; neutrophil/lymphocyte ratio index; neutrophil/monocyte ratio index; lymphocyte/monocyte ratio index; lymphocyte/eosinophil ratio index; leukocyte ratio and erythrocyte sedimentation rate index. Statistical analysis was performed using the Statistica 10 package. The Kruskal–Wallis and Mann–Whitney nonparametric tests were used to assess differences in the groups. The critical level of statistical significance when testing scientific hypotheses was p 0.05. RESULTS: At all stages of cataract maturity, before and after surgery, unidirectional changes in the hematological indices were revealed: the lymphocyte and eosinophil ratio decreased (1.4–2.0; p=0.01), the neutrophils and monocytes (1.3–2.1; p=0.04), lymphocytes and monocytes (1.4–2.5; p=0.02) ratios, leukocytes and erythrocyte sedimentation rate (2.9–6.8; p=0.01) increased. In immature cataract, the intoxication index according to the hematological indices increased by 2 times in the dynamics of surgical treatment. At the same time, multidirectional changes in the hematological indices were revealed in cortical and subcapsular opacities of the lens, unidirectional changes — in nuclear and total opacities. CONCLUSION: Patients with nuclear and total cataracts have the greatest number of disturbances in the ratio of cell populations according to hematological indices, therefore they constitute a risk group for the development of complications.

Congenital cataract with embryonic nuclear opacity

Congenital cataract with embryonic nuclear opacity

Tear Film Hyperosmolarity is Associated with Increased Variation of Light Scatter Following Cataract Surgery.

To study the association between tear film hyperosmolarity and ocular light scatter in a cataract surgery population. Contiguous, 20-second objective scatter index (OSI) scans were recorded in hyperosmolar (≥320 mOsm/L) and normal subjects (<308 mOsm/L) with cataract nuclear opacity ≥3. OSI was measured at screening, baseline and 90 days following surgery. Along with symptoms of ocular surface disease, slit-lamp examination included corneal staining (0-3), tear film breakup time (TBUT) and evaluation of meibomian gland disease (MGD). An additional cohort of hyperosmolar subjects were measured for OSI at screening, baseline, and 5, 10, 15 and 30 minutes following instillation of 0.18% sodium hyaluronate (HA). Thirty-one eyes of 31 patients were included. There was a significant difference in post-operative OSI variation when comparing hyperosmolar (0.65±0.30, N=11) to normal subjects (0.33±0.11, N=10, p=0.005). Of note, there were no significant differences in OSI variation when subjects were sorted by staining (p=0.9), TBUT (p=0.7), symptoms (p=0.7), or MGD status (p=0.9). Instillation of 0.18% HA (N=10) did not alter OSI at 5 minutes, but significant reductions in OSI of 28.8%, 38.5% and 36.7% (all p < 0.001) were observed at 10, 15 and 30 minutes. Hyperosmolar patients exhibited significantly increased variation in light scatter following cataract surgery that was undifferentiated by staining or TBUT. Elevated osmolarity may be indicative of light scatter equivalent to that of a grade 2-3 cataract.

Intraoperative quantitative crystalline lens nuclear opacities analysis based on crystalline lenSx platform

PurposeThe main objective is to quantify the lens nuclear opacity using spectral-domain optical coherence tomography (SD-OCT) and to evaluate its association with Lens Opacities Classification System III (LOCS-III) system, lens thickness (LT), and surgical parameters. The secondary objective is to assess the diagnostic model performance for hard nuclear cataract.MethodsThis study included 70 eyes of 57 adults with cataract, with 49 (70%) and 21 (30%) in training and validation cohort, respectively. Correlations of the average nuclear density (AND) /maximum nuclear density (MND) with LOCS-III scores, LT, and surgical parameters were analyzed. Univariate and multivariate logistic regression analysis, receiver operating characteristic curves and calibration curves were performed for the diagnostic of hard nuclear cataract.ResultsThe pre-operative uncorrected distance visual acuity (UDVA), intraocular pressure (IOP), mean axial length (AL), and LT were 1.20 ± 0.47 log MAR, 15.50 ± 2.87 mmHg, 27.34 ± 3.77 mm and 4.32 ± 0.45 mm, respectively. The average nuclear opalescence (NO) and nuclear colour (NC) scores were 3.61 ± 0.94 and 3.50 ± 0.91 (ranging from 1.00 to 6.90), respectively. The average AND and MND were 137.94 ± 17.01 and 230.01 ± 8.91, respectively. NC and NO scores both significantly correlated with the AND (rNC = 0.733, p = 0.000; rNO = 0.755, p = 0.000) and MND (rNC = 0.643, p = 0.000; rNO = 0.634, p = 0.000). In the training cohort, the area under the curve (AUC) of the model was 0.769 (P < 0.001, 95%CI 0.620–0.919), which had a good degree of differentiation (Fig. 2a). The calibration curve showed good agreement between predicted and actual probability.ConclusionThe nuclear density measurement on SD-OCT images can serve as an objective and reliable indicator for quantifying nuclear density.

Nuclear Grades based on Lens Opacities Classification System III associated with Phacoemulsification Parameters and Postoperative Central Corneal Thickness

Abstract&#x0D; Introduction &amp; Objectives : To determine association of nuclear cataract grades based on Lens Opacities Classification System (LOCS) III with phacoemulsification parameters and postoperative Central Corneal Thickness (CCT) and visual acuity.&#x0D; Methods : This was a prospective observational study in patient with uncomplicated senile cataract who gave consent and underwent phacoemulsification. Institutional Ethics Committee clearance was taken for the study. Preoperative nuclear cataract was evaluated using Lens Opacities Classification System (LOCS) III. Only nuclear grading NO and NC was obtained. All procedures was performed using peristaltic phaco machine and in the bag IOL implantation. Phacoemulsification parameters (US Total Time and CDE) were noted and compared in different grades of cataract. CCT change was recorded at day one after surgery.&#x0D; Results : Forty-six patients were evaluated. The mean USTT was 120.85 (56-252) seconds, mean CDE was 21.10 (5.70 – 43.38), and mean CCT change after surgery was 81.54(27 – 240). Nuclear grading of LOCS also had linear correlation with US Total Time (NO p&lt;0.001, r=0.734; NC p&lt;0.001, r=0.790) and CDE (NO p&lt;0.001, r=0.728; NC p&lt;0.001, r=0.685). There was significant correlation between CCT change with postoperative VA (p=0.002, r=0.443) and CDE (p&lt;0.001, r= 0.553). CCT change also correlate with nuclear opacity (p=0.012, r=0.367) and nuclear color (p=0.035, r=0.312).&#x0D; Conclusion : Nuclear grading of LOCS III related to the amount of time and energy used in phacoemulsification, and also CCT change after surgery as a qualitative measurement of corneal edema. Increasing postoperative CCT affected patient's visual acuity after cataract surgery.

Asteroseismic Inversions for Internal Sound Speed Profiles of Main-sequence Stars with Radiative Cores

The theoretical oscillation frequencies of even the best asteroseismic models of solar-like oscillators show significant differences from observed oscillation frequencies. Structure inversions seek to use these frequency differences to infer the underlying differences in stellar structure. While used extensively to study the Sun, structure inversion results for other stars have so far been limited. Applying sound speed inversions to more stars allows us to probe stellar theory over a larger range of conditions, as well as look for overall patterns that may hint at deficits in our current understanding. To that end, we present structure inversion results for 12 main-sequence solar-type stars with masses between 1 and 1.15 M ⊙. Our inversions are able to infer differences in the isothermal sound speed in the innermost 30% by radius of our target stars. In half of our target stars, the structure of our best-fit model fully agrees with the observations. In the remainder, the inversions reveal significant differences between the sound speed profile of the star and that of the model. We find five stars where the sound speed in the core of our stellar models is too low and one star showing the opposite behavior. For the two stars in which our inversions reveal the most significant differences, we examine whether changing the microphysics of our models improves them and find that changes to nuclear reaction rates or core opacities can reduce, but do not fully resolve, the differences.

Comparison of visual outcomes in adult patients with different types of developmental cataracts after toric multifocal intraocular lenses implantation

Purpose To analyze and compare the visual performance and patient satisfaction following the implantation of toric multifocal intraocular lenses (TMIOLs) in adult patients with different types of developmental cataracts (DC) accompanied by corneal astigmatism (CA).Methods This is a prospective observational cohort study. Patients diagnosed with DC aged 18–30 years were divided into three groups according to the anatomic location of the lens opacity: cortical, nuclear, and posterior subcapsular (PSC) groups, and implanted with TMIOLs. Visual acuity (VA), postoperative refractive astigmatism (RA), intraocular lens (IOL) rotation, high-order aberrations (HOAs), modulation transfer function (MTF) curve, and Strehl ratio were compared. The functional vision and incidence of photic phenomena were surveyed using questionnaires.Results Fifty-five eyes of 37 patients were enrolled and completed a 1-year follow-up. The mean CA was 2.06 ± 0.79 D preoperatively, and the mean RA was 0.29 ± 0.30 D 3-month postoperatively. The IOL rotation was 2.48° ± 1.89°, with no deviation > 10°. At 12 months, mean uncorrected distance VA improved from 0.93 ± 0.41 preoperatively to 0.08 ± 0.08 logarithm of the minimum angle of resolution (logMAR), mean uncorrected near VA increased from 0.45 ± 0.30 preoperatively to 0.12 ± 0.11 logMAR, and mean uncorrected intermediate VA was 0.14 ± 0.08 logMAR. The cortical and nuclear groups displayed better improvements in uncorrected near and intermediate VA than that in the PSC group. Similar results were observed in the 3-month defocus curves, HOAs, MTF curve, halo incidence, and near vision satisfaction.ConclusionIn adult patients with DC accompanied by CA, TMIOLs implantation achieved good postoperative visual outcomes and significantly reduced glasses dependency. Patients with cortical or nuclear lens opacity showed better whole-course VA and quality of vision, while patients with PSC opacity showed unsatisfactory near vision and suffered more photic phenomena.

Risk Factor of Cataract Formation after Penetrating Keratoplasty

Introduction: Post-corneal graft cataract is a not negligible complication. Its occurrence rate varies from 0.4% (2) to 32% (3) according to series, it can present itself in the form of nuclear, cortical and posterior capsular opacities. Its treatment corresponds to a usual cataract surgery by phacoemulsification with implantation in the capsular bag. Our work aims to identify and analyze the risk factors for the development of cataract after keratoplasty. Materials and Methods: This is an analytical study conducted within the Ophthalmology Service B at the Rabat Specialty Hospital on 58 patients who underwent penetrating keratoplasty. The main criteria studied were: age; sex; indication for surgery and average dose of corticosteroids. Statistical calculations were made using the SPSS 10.0 software for Windows. A p value &lt;0.05 was considered significant. The average follow-up was 24 months. Results: Cataract after corneal transplantation was observed in 10 cases (17.2%). The mean age at the time of cataract diagnosis was 55 years, with extremes ranging from 40 to 70 years? It developed in 7 of the 33 female cases (21%), and in 3 of the 25 male cases (12%). The onset delay ranged between 16 and 24 months, with a mean delay of 18 months after the penetrating keratoplasty. The most frequent type was nuclear cataract (8 of 10 eyes, 80%), posterior subcapsular cataract developed in one eye (10%) and cortical-nuclear cataract in one eye (10%). It developed in 4 of the 9 cases operated for corneal dystrophies (44.4%), in 3 of the 11 cases operated for sequelae of infectious keratitis (27.2%), in 2 of the 13 cases operated for posttraumatic opacity (15%) and in 1 of the 20 cases operated for keratoconus (5%). In our study, only age and operative indication of the graft were considered as risk factors for the development of cataract after corneal transplantation (p&lt;0.05). The preoperative visual acuity, the patient’s sex.

Efficacy of a new fragmentation pattern in femtosecond laser-assisted cataract surgery with the Ziemer FEMTO LDV Z8.

To determine the efficacy of different fragmentation patterns in femtosecond laser-assisted cataract surgery (FLACS) using Ziemer FEMTO LDV Z8. We compared three different types of surgery: conventional cataract surgery (CCS), FLACS with conventional radial slices (named No-Spiderweb), and FLACS with a novel fragmentation pattern (radial slices combined with one or two rings) called "Spiderweb." Visual acuity (VA), nuclear opacity (NO) according to the Lens Opacities Classification System (LOCS lll), effective phacoemulsification time (EPT) and vacuum time were obtained for 845 eyes. Using FLACS (Spiderweb + No-Spiderweb), EPT was significantly reduced by 26% compared to CCS (FLACS: 2.46 ± 2.60s; CCS: 3.34 ± 2.89s; ΔM = - 0.88s, p < .001). Furthermore, EPT as a function of progression of lens opacity was found to be not only lower in Spiderweb compared to CCS, but also in comparison with No-Spiderweb. At NO3, a significant reduction of 65% in EPT was observed by using Spiderweb compared to CCS (Spiderweb:0.68 ± 1.23 s; CCS: 1.96 ± 1.53 s; ΔM = - 1.28 s, p <.001). Interestingly, EPT at NO3 was also significantly reduced by 57% in Spiderweb compared to No-Spiderweb (Spiderweb:0.68 ± 1.23 s; No-Spiderweb: 1.57 ± 1 .59 s; ΔM = - 0.90 s, p <.001). The use of Spiderweb only marginally extends the vacuum time compared to No-Spiderweb by 11s (Spiderweb:209.13 ± 35.83s; No-Spiderweb: 198.35 ± 36.84s; p = .003) and the postoperative improved VA showed no significant difference among the different types of surgery (all ps ≥ .05). FLACS significantly reduces EPT compared to CCS. Furthermore, the novel Spiderweb pattern significantly reduces EPT in patients with a cataract of NO3 compared to CCS, but also to FLACS with the existing radial pattern (No-Spiderweb).

Innovative Technologies in the Monitoring of the Age-Related Cataract

Literature review is devoted to modern high-technology instrumental methods of the lens evaluation, which have been developed to improve efficiency of the diagnostics and management of cataract in ophthalmological clinical practice. The slit-lamp examination of lens and retroillumination images are used for subjective assessment of cataract according to LOCS III grading system. Currently objective methods of lens evaluation have practical value and provide information about early age-related changes of crystalline lens with the quantitative assessment of the severity of opacities including the optical and ultrasound examinations. Optical methods include densitometry using Scheimpflug images obtained from applications to quantify the localization of lens opacities and their progression rate. Another method is the intensity distribution analysis of the wave front of the optical aberrations according to grading cataract severity with the objective scatter index (OSI) obtained by double-pass technology. Moreover the optical quantitative assessment of lens opacities is carried out by the Shack—Hartmann wave front sensor to identify the grade of nuclear opalescence (N-type) with the Lens Opacities Classification System III. This method is very helpful in nuclear cataract. Swept source optical coherent tomography (SS-OCT) with variable length of wave and high frequency detector is used for the density measurements of nuclear and cortical opacities of lens imaging in micro- and macro dimensional scale. Ultrasound biomicroscopy is the most informative ultrasonic diagnostic method for the evaluation of acoustic density and early age-related changes of lens. Current high-informative methods of quantitative assessment of the optical density of lens are helpful in determination of indications for surgery, the optimization of phacoemulsification settings and prevention of intraoperative complications. The use of high-technologic methods demonstrated the effectiveness of eye drops 0,005 % pirenoxine in early lens opacities management.

In situ assessment of lens elasticity with noncontact optical coherence elastography.

Lens biomechanics has great potential for application in clinical diagnostics and treatment monitoring of presbyopia and cataracts. However, current approaches to lens elastography do not meet the desired safety or sensitivity for clinical application. In this regard, we propose a noncontact optical coherence elastography (OCE) method to facilitate quantitative in situ imaging of lens elasticity. Elastic waves induced by air-pulse stimulation on the limbus propagate to the lens and are then imaged using custom-built swept-source optical coherence tomography to obtain the elastic wave velocity and Young's modulus. The proposed OCE method was first validated by comparing the results of in situ and in vitro measurements of porcine lenses. The results demonstrate that the Young's modulus measured in situ was highly consistent with that measured in vitro and had an intraclass correlation coefficient of 0.988. We further investigated the elastic changes induced by cold storage and microwave heating. During 36-hour cold storage, the mean Young's modulus gradually increased (from 5.62 ± 1.24 kPa to 11.40 ± 2.68 kPa, P < 0.0001, n = 9) along with the formation of nuclear opacities. 15-second microwave heating caused a greater increase in the mean Young's modulus (from 6.86 ± 1.21 kPa to 25.96 ± 8.64 kPa, P < 0.0025, n = 6) without apparent cataract formation. Accordingly, this study reports the first air-pulse OCE measurements of in situ lenses, which quantified the loss of lens elasticity during simulated cataract development with good repeatability and sensitivity, thus enhancing the potential for adoption of lens biomechanics in the clinic.

Anterior Umbilication of Lens in a Family with Congenital Cataracts Associated with a Missense Mutation of MIP Gene.

Congenital cataracts (CCs) have significant genotypic and phenotypic heterogeneity. The major intrinsic protein (MIP) gene, one of the causative genes of CCs, plays a vital role in maintaining the homeostasis and transparency of the lens. In this study, we identified a unique phenotype of anterior umbilication of the lens in a four-generation pedigree with CCs. All patients in the observed family had nystagmus, nuclear cataracts, and elongated axial lengths compared with their healthy counterparts except for patient I:2, whose axial length was unavailable, and patientII:4, who had total cataracts. We confirmed, using Sanger sequencing based on whole-exon sequencing (WES) data, that all patients carried a heterozygous variant NM_012064.4:c.97C > T (NP_036196.1:p.R33C) in their MIP gene. To our knowledge, 29 variants of the human MIP gene and the relative phenotypes associated with CCs have been identified. Nevertheless, this is the first report on the anterior umbilication of the lens with nuclear or total opacity caused by the c.97C > T (p.R33C) variant in the MIP gene. These results also provide evidence that the elongated axial length might be associated with this variant. This study further confirms the phenotypic heterogeneity of CCs.

Prevalence and patterns of refractive error among adults in Sagamu, South-West Nigeria

Background: The study was part of community-based research towards strengthening the provision of optical services within a local governmental area in Nigeria.Aim: To describe the prevalence of refractive errors in the southwestern Nigerian adult population.Setting: Adults of age 30 years and above who were regular residents of the local governmental area.Methods: A multistage stratified random cluster sampling method was used to select the subjects. The sampling unit was the different households. A random sample of them were refracted and then refractive errors were analysed. Analyses excluded participants with history of cataract surgery. Associations with myopia (−0.50 dioptres [D] or more) and hyperopia (≥ 0.50 D) were evaluated in logistic regression analyses.Results: The prevalence of refractive error in the study sample was 33.8% (95% confidence level [CI]: 27.1–34.4) using study participants with 6/9 presenting visual acuity but improvement by at least a line with pin hole. The prevalence of hyperopia was 46.9% and higher in women (51.8%), while that of myopia was 21.9% but higher in men (25.0%). The prevalence of hyperopia increased from 29% for 40–49 years of age to 65% for 50–59 years of age and tended to decline thereafter. Prevalence of myopia decreased from 17% in persons 40–49 years of age to 11% in those 50–59 years of age but increased after 60 years of age. A higher prevalence of myopia was positively associated (p 0.05) with lifetime occupations requiring near work, nuclear opacities, posterior subcapsular opacities and glaucoma. Factors associated with hyperopia were the same as for myopia, except for occupation, and in the opposite direction.Conclusion: The high prevalence of refractive errors strongly supports the need for an affordable and accessible optical service in the local government.

Inhibitory effect of lanosterol on cataractous lens of cynomolgus monkeys using a subconjunctival drug release system.

ABSTRACTBackgroundTo evaluate the effect of lanosterol on cataractous lens of cynomolgus monkeys using a subconjunctival drug release system.MethodsNine elder cynomolgus monkeys were used, consisting of three monkeys without cataract as controls, three monkeys with naturally occurring cortical cataract, and three monkeys with nuclear cataract as intervention groups. Nanoparticulated thermogel with lanosterol and fluorescein was administered by subconjunctival injection in the monkeys with cataract. Fluorescence changes of injected thermogel and cataract progression were observed. Lanosterol concentration in aqueous humor, solubility changes in lens proteins, and oxidative stress levels were analyzed in the lenses of the control and intervention groups.ResultsInjected thermogel showed decreased fluorescence during follow up. Lanosterol concentration in aqueous humor increased in the first 2 weeks and then gradually decreased, which was in accordance with the changes in cortical lens clarity. However, lenses with nuclear opacification showed little change. In the cortical region of lenses with cortical cataract, solubility of α-crystallin was significantly increased after administration of lanosterol, as well as the reduction of oxidative stress.ConclusionsWe demonstrated the effect of lanosterol on cataract progression based on in vivo models of primates. Lanosterol showed a short-term and reliable reversal effect on reducing cataract severity in cortical cataract in the early stages, possibly due to the increase in the solubility of lens proteins and changes in the oxidative stress status. Lanosterol administration using subconjunctival drug release system could be a promising nonsurgical approach for future clinical studies of cataract prevention and treatment.

Combination of Lanosterol and Nilvadipine Nanosuspensions Rescues Lens Opacification in Selenite-Induced Cataractic Rats.

It has recently been reported that lanosterol (LAN) plays a preventive role against lens opacification through the reversal of crystalline aggregation. However, the effect of LAN is not sufficient to restore lens transparency. In this study, we designed ophthalmic nanosuspensions (LAN-ONSs and NIL-ONSs) based on LAN and nilvadipine (NIL), which can counteract cataract-related factors (e.g., enhanced Ca2+ and calpain levels), and investigated whether the combination of LAN-ONSs and NIL-ONSs can restore the nuclear lens opacity in sodium-selenite-induced cataractic rats (cataractic rats). The mean particle sizes of the LAN-ONSs and NIL-ONSs were 108.8 nm and 89.0 nm, respectively. The instillation of the LAN-ONSs or NIL-ONSs successfully delivered the drugs (LAN or NIL) into the lenses of the rats, although the instillation of LAN-ONSs or NIL-ONSs alone did not increase lens transparency in the cataractic rats. On the other hand, the cataract-related factors (enhanced Ca2+ and calpain levels) were significantly alleviated by the combination of LAN-ONSs and NIL-ONSs; furthermore, the perinuclear refractile ring in the lens nucleus and enhanced number of swollen fibers were attenuated by the LAN-ONS and NIL-ONS combination. Moreover, the opacity levels in the cataractic rats were reduced after treatment with the combination of LAN-ONSs and NIL-ONSs. It is possible that the combination of LAN and NIL will be useful for the treatment of lens opacification in the future.

Oxidation of active cysteines mediates protein aggregation of S10R, the cataract-associated mutant of mouse GammaB-crystallin.

The Ser10 to Arg mutation in mouse γB-crystallin (MGB) has been associated with protein aggregation, dense nuclear opacity, and the degeneration of fiber cells in the lens core. Overexpression of the gap junction protein, connexin 46 (Cx46), was found to suppress the nuclear opacity and restore normal cell-cell contact. However, the molecular basis for the protein aggregation and related downstream effects were not evident from these studies. Here, we provide a comparison of the structures and solution properties of wild type MGB and the S10R mutant in vitro and show that, even though the mutation does not directly involve cysteine residues, some cysteines in the mutant protein are activated, leading to the enhanced formation of intermolecular disulfide-crosslinked protein aggregates relative to the wild-type. This occurs even as the protein structure is essentially unaltered. Thus, the primary event is enhanced protein aggregation due to the disulfide crosslinking of the mutant protein. We suggest that these aggregates eventually get deposited on fiber cell membranes. Since the gap junction protein, Cx46 is involved in the transport of reduced glutathione, we posit that these deposits interfere in Cx46-mediated glutathione transport and facilitate the oxidative stress-mediated downstream changes. Overexpression of Cx46 suppresses such oxidative aggregation. These studies provide a plausible explanation for the protein aggregation and other changes that accompany this mutation. If indeed cysteine oxidation is the primary event for protein aggregation also in vivo, then the S10R mutant mouse, which is currently available, could serve as a viable animal model for human age-onset cataract.

Eye lens opacities and cataracts among physicians and healthcare workers occupationally exposed to radiation: A systematic review and meta-analysis.

To evaluate the risk of developing eye lens opacities and cataracts among physicians and healthcare workers occupationally exposed to radiation. Our literature search captured articles published in Embase, Web of Science, PubMed, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature, and Google Scholar databases until September 2021. Then, we retrieved articles reporting cataracts and eye lens opacities induced by radiation exposure among healthcare professionals. The outcomes of interest were cataracts, nuclear opacity, cortical opacity, posterior subcapsular opacity, and any lens opacity. Of the 4123 articles identified, 15 studies met the inclusion criteria. Healthcare workers exposed to radiation had a significantly greater risk of posterior subcapsular cataracts (PSCs), cataracts, and any lens opacities than those of the non-exposed participants (p<0.05). The cortical opacity was not significantly different between the exposed and non-exposed participants (p>0.05). Radiation was not determined to be a risk factor for nuclear opacity as it was significantly greater in the control group than the exposed participants. Subgroup analysis revealed that nurses had the highest risk for PSCs (risk ratio = 4.00), followed by interventional cardiologists (risk ratio = 3.85). The risk of posterior subcapsular opacities and cataracts is significantly higher in healthcare workers with occupational radiation exposure than in non-exposed workers, highlighting the necessity to enhance and promote the wearing of protective measures with high safety levels.

Learning Curve in Phaco Chop Cataract Surgery Using an Illuminated Chopper

Purpose: To confirm that the phaco chop method using an illuminated chopper (iChopper; Oculight, Seongnam, Korea) can reduce cataract surgery complications, and that even beginners can safely and effectively perform phaco chop.Methods: We retrospectively analyzed the medical records of the first 30 phaco chop cases using illuminated chopper of four cataract surgeons. Four ophthalmologists had a variety of empirical backgrounds, from those who have experienced more than 10,000 cataract surgery, to beginners who have experienced 20 cataract surgery.Results: Of the total 120 eyes, two eyes (1.67%) had posterior capsule rupture. The chopping method was changed from phaco chop to stop and chop in three eyes (2.5%) including one eye with brown cataract with pseudoexofoliation syndrome and two eyes with nuclear opacity grade ≥5.Conclusions: The rates of posterior capsule rupture of phaco chop using an illuminated chopper were very low in four surgeons with various experiences and who became proficient shortly in phaco chop.

Association of alkaptonuria and low dose nitisinone therapy with cataract formation in a large cohort of patients.

Homogentisic acid (HGA) lowering, disease modifying off‐label nitisinone therapy has been used in the United Kingdom National Alkaptonuria Centre (NAC) since 2012. This study evaluated the serendipitous observation of cataract in a large cohort of patients with the very rare disease alkaptonuria (AKU), over a 5‐year period. Patients with AKU who attended the NAC since 2012. Standard physical examination and ocular assessment, including photographs of the crystalline lens were taken before commencement of nitisinone 2 mg daily and annually over 5 years. Photographs were randomised and graded by two independent observers using the WHO cataract classification. AKU patients who did not receive nitisinone were included as a control group. HGA was measured on acidified 24 h urine (u‐HGA24) and HGA and tyrosine in fasting acidified serum samples (sHGA, sTYR) at each visit. Patients without suitable lens images were excluded. Cataract (mean grade 1) was noted at baseline in 47 out of 62 (76%) with a mean (SD) age of 44 (14) years. In nitisinone‐treated patients, there were significant increases in the mean grade of nuclear (0.18, p < 0.01) and cortical (0.38, p < 0.01) lens opacities over the mean duration of 4.93 years of the study. Worsening of the nuclear cataract and cortical lens opacities by at least 1 grade was noted in 14 out of 46 (30%) and 11 out of 46 (24%) patients, respectively. There is an increased prevalence and progression of cataract in AKU and a possible association of nitisinone with cataract progression.