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AIM: To evaluate the neutrophil-to-lymphocyte ratio(NLR)in patients with retinitis pigmentosa(RP)complicated with cataract, and to explore its correlation with the clinical characteristics of RP patients complicated with cataract.METHODS: The retrospective study included 79 RP patients(125 eyes)complicated with cataract who received cataract surgery at our hospital from January 2008 to December 2018, among which 63 cases(63 eyes)were finally enrolled in the RP complicated with cataract group after the exclusion of patients with early age of onset. Another 63 age- and sex-matched patients(63 eyes)with age-related cataract(ARC)who had cataract surgery during the same period in our hospital were enrolled in the ARC group. The clinical data and NLR were collected, and the correlation of clinical manifestations with NLR in RP patients complicated with cataract was analyzed.RESULTS: The NLR in RP patients complicated with cataract was significantly higher than that in the ARC group [1.79(1.32, 2.27)vs 1.58(1.32, 1.98), P=0.032]. NLR was associated with the severity of posterior subcapsular cataract(PSC), zonular deficiency, and preoperative best-corrected visual acuity(>1 LogMAR). Receiver operating curve showed that NLR ≥1.36 could predict higher degrees(>P1)of RP complicated PSC(AUC=0.803, 95%CI 0.672-0.934, P=0.002), NLR ≥2.12 could predict zonular weakness in RP patients complicated with cataract(AUC=0.796, 95%CI 0.665-0.928, P=0.002), while NLR ≥1.51 could predict RP patients with worse preoperative BCVA(AUC=0.667, 95%CI 0.540-0.793, P=0.015).CONCLUSION: NLR in RP patients complicated with cataract is significantly higher than that in ARC patients, and it is correlated with the clinical manifestations of RP patients with cataract. NLR can be used as a potential predictor to evaluate the severity of clinical manifestations of RP complicated with cataract.

Background Posterior subcapsular cataracts (PSC) and raised intraocular pressure (IOP) are the most common ocular complications of oral steroid administration, particularly following long-term use or treatment with high doses. Objective To evaluate the association between cumulative steroid dose and duration of treatment with the occurrence of PSC and raised IOP, as well as its associated factors in children with idiopatic nephrotic syndrome (INS). Methods This cross-sectional study included children aged 4–18 years with INS who received oral steroid therapy for at least six consecutive months. Patients underwent complete eye examinations by an ophthalmologist to evaluate their visual acuity as well as the occurrence of PSC and/or raised IOP. Results Of 92 subjects, 19.6% had PSC, 12% had raised IOP, and one had a best corrected visual acuity (BCVA) of

Purpose: To evaluate common morphological types of cataracts in patients with hypertension (HTN) alone (hypertensive patients) planned for cataract surgery. Methods: It is a prospective cross-sectional study. It was conducted in the Department of Ophthalmology at a tertiary eye care centre from January 2022 to June 2022. Hypertensive patients, without any other systemic diseases, who presented with cataract in either of their eyes were included in the study. The classification of cataract was performed according to the Lens Opacities Classification System III. Results: Two hundred and eighty eyes of 140 patients were included in the study. The mean age of presentation was 64.9 ± 7.38 years (median 67 years; range 39–81 years). There were 63 (45%) males, and the rest were females. Of 140, 14 patients were below the age of 55 years, 2 patients were above 75 years, and the majority (42 patients) belonged to the age group between 67 and 70 years. Nuclear sclerosis (NS) cataract was the most common morphological type found in the eyes of hypertensive patients followed by posterior subcapsular cataract (PSC). PSC significantly correlated with HTN when compared to other types of cataracts excluding NS (P < 0.0001). No significant relation was found between the grade of HTN and the grade of NS. Conclusion: Apart from the risk of formation of any type of cataract, NS and PSC were more commonly found in patients with HTN. Moreover, PSC was closely related to HTN when compared to other types of cataracts excluding NS.

Background: Our study aims to develop an artificial intelligence-based high-precision cataract classification and grading evaluation network using fundus images. Methods: We utilized 1,340 color fundus photographs from 875 participants (aged 50-91 years at image capture) from the Beijing Eye Study 2011. Four experienced and trained ophthalmologists performed the classification of these cases based on slit-lamp and retro-illuminated images. Cataracts were classified into three types based on the location of the lens opacity: cortical cataract, nuclear cataract, and posterior subcapsular cataract. We developed a Dual-Stream Cataract Evaluation Network (DCEN) that uses color photographs of cataract fundus to achieve simultaneous cataract type classification and severity grading. The accuracy of severity grading was enhanced by incorporating the results of type classification. Results: The DCEN method achieved an accuracy of 0.9762, a sensitivity of 0.9820, an F1 score of 0.9401, and a kappa coefficient of 0.8618 in the cataract classification task. By incorporating type features, the grading of cataract severity can be improved with an accuracy of 0.9703, a sensitivity of 0.9344, an F1 score of 0.9555, and a kappa coefficient of 0.9111. We utilized Grad-CAM visualization technology to analyze and summarize the fundus image features of different types of cataracts, and we verified our conclusions by examining the information entropy of the retinal vascular region. Conclusion: The proposed DCEN provides a reliable ability to comprehensively evaluate the condition of cataracts from fundus images. Applying deep learning to clinical cataract assessment has the advantages of simplicity, speed, and efficiency. [ABSTRACT FROM AUTHOR]

The mutations in the αA-crystallin (CRYAA) gene may contribute to the development of age-related cataract (ARC). In this study, we searched for single nucleotide polymorphisms (SNP) in exons of CRYAA and investigated the associations between the identified SNPs and the subtypes of ARC. Peripheral venous blood was collected for the extraction of genomic DNA. Three exons of CRYAA were sequenced to detect SNPs. The frequency distributions of alleles and genotypes were compared between the ARC and control groups. There were 618 patients with various subtypes of ARC (nuclear cataract [NC], cortical cataract [CC], posterior subcapsular cataract [PSC]). The control group comprised 236 patients. The incidence of early-onset cataract was significantly greater in PSC patients (P =.002 for NC; P =.036 for CC). One SNP was detected in exon 3 of CRYAA (rs76740365 G>A). When the distribution of rs76740365 was compared among the ARC subtypes, only the difference between the PSC group and the control group was statistically significant (allele frequency: P =.000057, OR 2.945; genotype distribution frequency: P =.000458). The heterozygote genotype (GA) carried a significantly greater risk than the homozygous wild-type genotype (GG) by 1.742 times for all types of cataracts and 2.369 times for the PSC subtype. The SNP rs76740365 G>A in exon 3 of the CRYAA gene is associated with greater susceptibility of ARC, particularly the PSC subtype. Individuals carrying the SNP rs76740365 G>A may be more likely to develop PSC at a younger age than other subtypes. [ABSTRACT FROM AUTHOR]

Abstract Background Pigmented paravenous retinochoroidal atrophy (PPRCA) is a rare fundus disease characterized by the presence of osteoblast-like pigment, atrophy of retinal pigment epithelium (RPE), and choroid deposition along the large retinal veins. Case presentation A 55-year-old Chinese female presented with right eye distention and bilateral vision loss. Osteocyte-like pigmentation and retinal choroidal atrophy distributed along the large retinal veins were seen in the fundus of bilateral eyes. The atrophy in the left eye was more severe compared to the right eye. The patient also presented with bilateral acute angle-closure glaucoma (AACG) and posterior subcapsular cataract (PSC) accompanied with anterior segmental manifestations, similar to the complications of retinitis pigmentosa (RP). The patient underwent ultrasound biomicroscopy (UBM), Humphrey field analyser (HFA), optical coherence tomography (OCT), fundus autofluorescence (FAF), fluorescein fundus angiography (FFA), electroretinogram (ERG), and electrooculography (EOG), all of which confirmed the aforementioned diagnose. Conclusion PPRCA is a rare disease of unknown etiology. The patient in this case presented with complications similar to those of RP, and the two conditions may share a genetic basis. Further studies are needed to confirm this relationship.

To determine the prevalence of cataract and its relationship with some determinants in individuals above 60 years. Of 3792 subjects that were invited, 3310 participated in the study (response rate = 87.31%). All subjects underwent full optometric, slit lamp, and fundoscopic examinations. Then, their lenses were evaluated according to the World Health Organization cataract grading system after pupil dilation. Age- and sex-standardized prevalence with 95% confidence interval (CI) of nuclear, cortical, posterior subcapsular cataracts (PSC), any type cataract, and all lens change was 53.09% (49.80 to 56.35), 23.02% (20.87 to 25.32), 5.57% (4.62 to 6.70), 58.78% (55.65 to 61.83), and 72.49% (70.14 to 74.71), respectively. Any type, nuclear, cortical, and PSC cataracts, had a positive association with age and an inverse association with education. Moreover, the prevalence of cortical and PSC cataract had an inverse association with economic status. Among all variables, age was the strongest determinant for cataract and its subtype. This study found a higher prevalence of cataract compared to some previous studies such that about two-thirds of the geriatric population had cataract in the past or at the time of the study. Considering the association of cataract with variables such as economic status and education level, it seems that training and increased awareness and knowledge of the elderly population regarding the importance of eye care by physicians plays an important role in reducing the burden of cataract. [ABSTRACT FROM AUTHOR]

To develop deep learning models to perform automated diagnosis and quantitative classification of age-related cataract from anterior segment photographs. DeepLensNet was trained by applying deep learning models to the Age-Related Eye Disease Study (AREDS) dataset. A total of 18 999 photographs (6333 triplets) from longitudinal follow-up of 1137 eyes (576 AREDS participants). Deep learning models were trained to detect and quantify nuclear sclerosis (NS; scale 0.9–7.1) from 45-degree slit-lamp photographs and cortical lens opacity (CLO; scale 0%–100%) and posterior subcapsular cataract (PSC; scale 0%–100%) from retroillumination photographs. DeepLensNet performance was compared with that of 14 ophthalmologists and 24 medical students. Mean squared error (MSE). On the full test set, mean MSE for DeepLensNet was 0.23 (standard deviation [SD], 0.01) for NS, 13.1 (SD, 1.6) for CLO, and 16.6 (SD, 2.4) for PSC. On a subset of the test set (substantially enriched for positive cases of CLO and PSC), for NS, mean MSE for DeepLensNet was 0.23 (SD, 0.02), compared with 0.98 (SD, 0.24; P = 0.000001) for the ophthalmologists and 1.24 (SD, 0.34; P = 0.000005) for the medical students. For CLO, mean MSE was 53.5 (SD, 14.8), compared with 134.9 (SD, 89.9; P = 0.003) for the ophthalmologists and 433.6 (SD, 962.1; P = 0.0007) for the medical students. For PSC, mean MSE was 171.9 (SD, 38.9), compared with 176.8 (SD, 98.0; P = 0.67) for the ophthalmologists and 398.2 (SD, 645.4; P = 0.18) for the medical students. In external validation on the Singapore Malay Eye Study (sampled to reflect the cataract severity distribution in AREDS), the MSE for DeepSeeNet was 1.27 for NS and 25.5 for PSC. DeepLensNet performed automated and quantitative classification of cataract severity for all 3 types of age-related cataract. For the 2 most common types (NS and CLO), the accuracy was significantly superior to that of ophthalmologists; for the least common type (PSC), it was similar. DeepLensNet may have wide potential applications in both clinical and research domains. In the future, such approaches may increase the accessibility of cataract assessment globally. The code and models are available at https://github.com/ncbi/deeplensnet. [ABSTRACT FROM AUTHOR]

Background: Pigmented paravenous retinochoroidal atrophy (PPRCA) is a rare fundus disease characterized by the presence of osteoblast-like pigment, atrophy of retinal pigment epithelium (RPE), and choroid deposition along the large retinal veins.Case Presentation: A 55-year-old Chinese female presented with right eye distention and bilateral vision loss. Osteocyte-like pigmentation and retinal choroidal atrophy distributed along the large retinal veins were seen in the fundus of bilateral eyes. The atrophy in the left eye was more severe compared to the right eye. The patient also presented with bilateral acute angle-closure glaucoma (AACG) and posterior subcapsular cataract (PSC) accompanied with anterior segmental manifestations, similar to the complications of retinitis pigmentosa (RP). The patient underwent ultrasound biomicroscopy (UBM), Humphrey field analyser (HFA), optical coherence tomography (OCT), fundus autofluorescence (FAF), fluorescein fundus angiography (FFA), electroretinogram (ERG), and electrooculography (EOG), all of which confirmed the aforementioned diagnose.Conclusion: PPRCA is a rare disease of unknown etiology. The patient in this case presented with complications similar to those of RP, and the two conditions may share a genetic basis. Further studies are needed to confirm this relationship. [ABSTRACT FROM AUTHOR]

Abstract Background This study aims to compare the levels of intraocular cytokines between Fuchs uveitis syndrome (FUS) eyes and the senile cataract eyes. The association between inflammatory cytokine levels and cataract severity in FUS is evaluated to find the possible mechanism of cataract in FUS eyes. Methods A retrospective study of 28 eyes with FUS was performed. Auxiliary examinations were performed, including ophthalmic examinations, laser flare-cell photometry, and levels of inflammatory cytokines in the aqueous humor were measured. The control group included 25 eyes with senile cataract. Data on the aqueous humor inflammatory cytokines were compared between the two groups. The association between the aqueous humor cytokine levels and severity of posterior subcapsular cataract was assessed. Results There were 28 eyes with FUS in 27 patients. Unilateral involvement was noted in 26 patients (96.30%). Stellate keratic precipitates (KPs) were noted in 16 eyes (57.14%). Heterochromia was observed in 21.43% of affected eyes. Posterior subcapsular cataract (PSC) was observed in 16 of the 28 eyes. Eyes with FUS had significantly higher aqueous humor (AH) cytokine levels (VEGF, bFGF, IL-6, IL-8 and IL-10) compared with the control eyes (P

AIMS: The purpose of this study is to describe the clinical profile of children presenting with posterior lenticonus. We also report on visual outcomes following surgery in these patients. SUBJECTS AND METHODS: Medical records of patients with a diagnosis of posterior lenticonus between January 2000 and December 2016 were reviewed. Data collected included demographic details, preoperative, intraoperative details like type of intraocular lens (IOL) and surgery, and amblyopia therapy. Only the patients with a follow-up of at least 6 months from the time of presentation were included in the analysis. RESULTS: Forty-eight eyes with posterior lenticonus with at least 6 months of follow-up were studied. Twelve (25%) eyes had a preoperative posterior capsule (PC) dehiscence as seen on slit-lamp biomicroscopy or on ultrasonography. The mean presenting visual acuity in all eyes was 1.034 ± 0.56 logarithm of the minimum angle of resolution (logMAR) units. The mean final visual acuity in these patients was 0.57 ± 0.5 logMAR units. Postoperative visual acuity was found to have a borderline positive correlation with the presence of preoperative strabismus (P = 0.049). Younger age at presentation (P = 0.533) or the presence of preoperative PC dehiscence (P = 0.735) did not influence final visual acuity. CONCLUSION: Visual acuity improves following surgery with IOL implantation in children with posterior lenticonus and cataract. With the availability of foldable lenses and improved surgical techniques, it is possible to place the IOL in bag despite a preexisting posterior capsular dehiscence. Children with posterior lenticonus who present with strabismus are likely to have poorer visual outcomes.

Purpose: The role of inflammation in retinitis pigmentosa (RP) has been receiving additional attention. However, the association between inflammation and the clinical manifestations and complications of RP is still unclear. This study aimed to evaluate the neutrophil‐to‐lymphocyte ratio (NLR) of RP complicated with cataract and explore the correlations between the NLR and specific clinical features of RP. Methods: This retrospective study included 79 RP patients complicated with cataract (125 eyes) and 63 age‐ and sex‐matched patients (63 eyes) with age‐related cataract (ARC). Patients' ocular examination results were collected and complete blood count results were used to calculate NLRs. The correlations between the NLR of RP patients and the parameters of ocular examinations were analysed. Results: The NLRs of RP patients with cataracts were significantly higher than those of ARC (1.93 ± 0.83 versus 1.65 ± 0.59, p = 0.029). The NLRs increased with the severity of posterior subcapsular cataract (PSC), zonular deficiency, poor preoperative best‐corrected visual acuity (LogMAR>1), and visual field defects. Analysis of receiver operating characteristic curves suggested that NLR > 1.36 could predict higher degrees (PSC area >3%, >P1) of PSC (p = 0.002, 95% CI, 0.672–0.934), and that NLR > 2.12 could predict zonular weakness (p = 0.002, 95% CI, 0.665–0.928) in RP. Conclusion: The NLRs in RP patients with cataract are not only higher but also associated with several clinical manifestations of RP. The NLR can be a predictive biomarker of higher degrees of PSC (>P1) and zonular weakness in RP before cataract surgery. These results suggest that systemic inflammation may play a role in the pathogenesis of RP. [ABSTRACT FROM AUTHOR]

Background: Retinitis pigmentosa (RP) is an inherited retinal dystrophy characterized by progressive vision loss due to photoreceptor degeneration. Complicated cataract formation, particularly posterior subcapsular cataract (PSC), frequently occurs in RP and exacerbates the visual impairment. Cataract surgery may improve vision; however, the distinctive challenges of RP require specific considerations. This mini-review aims to provide a comprehensive overview of the RP-related cataract., Methods: A comprehensive literature review was conducted via PubMed/MEDLINE, spanning the period from January 1976 to June 2024, using the keywords "cataract," "cataract surgery," "cystoid macular edema," "hereditary retinal dystrophy," "retinitis pigmentosa," "posterior subcapsular cataract," "posterior capsular opacification," "zonular weakness," and "artificial intelligence." We aimed to evaluate cataract surgery in patients with RP, focusing on cataract formation, its surgical management, postoperative complications, patient follow-up, and visual outcomes. Relevant review articles, clinical trials, and case reports with related reference lists of these articles were included., Results: A total of 53 articles were examined in detail, including those identified through focused keyword searches and the reference lists of these articles. Cataract surgery in patients with RP generally results in substantial visual improvement. However, surgery can be complicated, particularly by zonular weakness and subluxation of the crystalline lens. These risks can be reduced by using capsular tension rings and employing meticulous surgical technique. Furthermore, postoperative complications, such as cystoid macular edema and posterior capsular opacification, are common. Despite these challenges, regular postoperative follow-up and appropriate management can help mitigate complications. Integrity of the ellipsoid zone and external limiting membrane on preoperative optical coherence tomographic examination are the main predictors of visual outcomes following cataract surgery; however, outcomes can vary. Though many patients experience significant visual improvement, some may experience limited benefits due to pre-existing advanced retinal degeneration., Conclusions: Cataract surgery may offer meaningful visual benefits in patients with RP; however, careful preoperative evaluation and meticulous surgical technique are required to address the possible challenges. Attentive postoperative care and follow-up are essential to optimize visual outcomes. Early surgical intervention can significantly improve the quality of life in selected candidates, and tailored approaches are necessary in patients with RP requiring cataract surgery. Further studies on the potential application of artificial intelligence to monitor postoperative recovery and detect complications may improve surgical outcomes and enhance patient care., Competing Interests: None., (© Author(s).)

Purpose: Early onset opacification of the lens (cataract) has been observed to be on the rise globally. This study was conducted to determine the various types of presenile cataract and to determine the probable risk factors associated with the occurrence of presenile cataract. Materials and Methods: Patients in the age group of 18–40 years attending the Out-Patient Clinic of the Ophthalmology Department who were found to have presenile cataract were recruited as cases. An equal number of consecutive patients of the same age group were included in the control group. Those who gave consent to participate in the study were interviewed through a preformed questionnaire and underwent a complete ocular examination and set of blood investigations. The type of cataract was noted, data obtained were compiled, and examination and investigations done were documented and analyzed using frequency distribution and Chi-squared test. Results: In total, 90 cases and 90 controls that fulfilled the inclusion criteria were recruited. Most common type of cataract was found to be posterior subcapsular cataract. Presenile cataract was observed to be significantly associated with tobacco intake (P = 0.035), hypercholesterolemia (P = 0.002), fuel exposure (P = 0.004), and lower socioeconomic status (P =

Background: This study aims to compare the levels of intraocular cytokines between Fuchs uveitis syndrome (FUS) eyes and the senile cataract eyes. The association between inflammatory cytokine levels and cataract severity in FUS is evaluated to find the possible mechanism of cataract in FUS eyes.Methods: A retrospective study of 28 eyes with FUS was performed. Auxiliary examinations were performed, including ophthalmic examinations, laser flare-cell photometry, and levels of inflammatory cytokines in the aqueous humor were measured. The control group included 25 eyes with senile cataract. Data on the aqueous humor inflammatory cytokines were compared between the two groups. The association between the aqueous humor cytokine levels and severity of posterior subcapsular cataract was assessed.Results: There were 28 eyes with FUS in 27 patients. Unilateral involvement was noted in 26 patients (96.30%). Stellate keratic precipitates (KPs) were noted in 16 eyes (57.14%). Heterochromia was observed in 21.43% of affected eyes. Posterior subcapsular cataract (PSC) was observed in 16 of the 28 eyes. Eyes with FUS had significantly higher aqueous humor (AH) cytokine levels (VEGF, bFGF, IL-6, IL-8 and IL-10) compared with the control eyes (P < 0.05). There was a statistically significant positive correlation between the severity of cataract and IL-6 and IL-8 levels in the AH (τ = 0.664 and 0.634, respectively; P = 0.001, P = 0.002, respectively).Conclusions: Expression of VEGF, bFGF, IL-6, IL-8 and IL-10 in the AH of FUS patients was significantly higher than in senile cataract eyes, and the aqueous humor levels of IL-6 and IL-8 were significantly positively associated with the severity of posterior subcapsular cataract. Our results imply that an inflammation mechanism may be involved in the early development of cataract in FUS. [ABSTRACT FROM AUTHOR]

AIMS: The purpose of this study is to describe the clinical profile of children presenting with posterior lenticonus. We also report on visual outcomes following surgery in these patients. SUBJECTS AND METHODS: Medical records of patients with a diagnosis of posterior lenticonus between January 2000 and December 2016 were reviewed. Data collected included demographic details, preoperative, intraoperative details like type of intraocular lens (IOL) and surgery, and amblyopia therapy. Only the patients with a follow-up of at least 6 months from the time of presentation were included in the analysis. RESULTS: Forty-eight eyes with posterior lenticonus with at least 6 months of follow-up were studied. Twelve (25%) eyes had a preoperative posterior capsule (PC) dehiscence as seen on slit-lamp biomicroscopy or on ultrasonography. The mean presenting visual acuity in all eyes was 1.034 ± 0.56 logarithm of the minimum angle of resolution (logMAR) units. The mean final visual acuity in these patients was 0.57 ± 0.5 logMAR units. Postoperative visual acuity was found to have a borderline positive correlation with the presence of preoperative strabismus (P = 0.049). Younger age at presentation (P = 0.533) or the presence of preoperative PC dehiscence (P = 0.735) did not influence final visual acuity. CONCLUSION: Visual acuity improves following surgery with IOL implantation in children with posterior lenticonus and cataract. With the availability of foldable lenses and improved surgical techniques, it is possible to place the IOL in bag despite a preexisting posterior capsular dehiscence. Children with posterior lenticonus who present with strabismus are likely to have poorer visual outcomes. [ABSTRACT FROM AUTHOR]

Importance Age‐related cataract is the leading cause of blindness worldwide. The pathological mechanisms causing this disease remain elusive. Background: To examine the involvement of uric acid (UA) in the pathogenesis of posterior subcapsular cataract (PSC). Design Retrospective study and experimental investigation. Participants: A total of 180 patients with PSC or non‐PSC were included. Methods: Samples obtained from the patients were used to analyse content of UA and for histochemical examinations. The effects of UA on human lens epithelial cells were also investigated. Main Outcome Measures: Aqueous humour UA and urate deposits. Results: The results showed a significant increase of aqueous humour UA in patients with PSC. After adjustment for potential confounders, elevated aqueous humour UA (odds ratio [OR] = 1.45) showed a stronger association with PSC than serum UA (OR = 1.10). Gomori methenamine silver staining revealed in PSC an intense deposit of urates in the lens fibres in equatorial regions, and in subcapsular fibres in posterior regions of the lens. Such staining was not detected in the lens with non‐PSC. Treatment with UA‐induced senescence and apoptosis in human lens epithelial cells in a dose dependent manner. Our results suggest that the elevated level of UA in aqueous humour causes a deposition of urates in human lens epithelium, which could possibly lead to dysfunction of these cells that generates opacification in PSC. Conclusions and Relevance: These findings indicate the local action of excessive UA in the pathogenesis of PSC. Control of serum UA level could delay the progression of PSC. [ABSTRACT FROM AUTHOR]

Since the exact development of posterior subcapsular cataracts (PSCs) is poorly understood, we review various risk factors and propose a two-stage etiology for PSCs. The biological mechanisms associated with age-related cataracts (primarily nuclear cataracts, cortical cataracts and PSCs) were reviewed in relation to selected risk factors that induce PSCs (including atopy, diabetes, hypoparathyroidism, myopia, retinitis, solar radiation, steroid use, uveitis, vitrectomy and ionizing radiation). We particularly focused on ionizing radiation, as this is known to be a risk factor specific to PSCs. Based on an analysis of the reviewed material, we propose a detailed explanation of the etiology of PSCs. Lens epithelial cells (LECs) and lens fiber cells are normally hypoxic and therefore very sensitive to changes in oxidative stress, as quantified by the radiation oxygen effect. We hypothesize that the development of PSC opacities is a two-stage process. Stage I, early in life, is driven by risk factors that promote oxidative stress and ion-pump disruption, harming lens fibers and causing aberrant LECs to proliferate and ectopically migrate as Wedl cells (perhaps by processes associated with an epithelial to mesenchymal transition) to the posterior pole region. After a latent period, in Stage II, the development of PSCs advances mainly due to chronic inflammation and other premature aging-related mechanisms that promote mature vacuolar or plaque PSC. This two-stage hypothesis of PSC etiology accounts for risk factors, such as aging, diabetes and ionizing radiation, which directly affects LECs and the lens. In addition, these risk factors can damage other ocular regions, such as the retina and vitreous, that also indirectly contribute to the development of PSCs. It is possible that the incidence of PSCs may be reduced by reversing the effects of Stage I through various means, including ocular antioxidants. [ABSTRACT FROM AUTHOR]

Purpose. Vitamin D insufficiency and age related cataract (ARC) are public health problems. We evaluated serum vitamin D levels in ARC patients. Method. A prospective hospital-based cross-sectional study was designed to measure the vitamin D status of patients with ARC. Patients have grouped either presence of any type of posterior subcapsular cataract (PSC) (group 1) or ARC without the PSC component (Group 2). After full ophthalmologic consideration, patients over 40 years of age with no history of ocular trauma, multivitamin supplement ingestion, chronic renal failure, thyroidectomy, parathyroidectomy, skin cancer, and cigarette smoking were included in the study. Results. Totally, 79 subjects of which 26 (32.9%) subjects in group 1 and 53 (67.1%) subjects in group 2 were included in the study. Group 1 had mean vitamin D levels of 17.31±13.30 ng/mL. Vitamin D levels in Group 2 were 13.34±7.87 ng/mL. Group 1 did not show vitamin D insufficiency (P = 0.31; one-sample t-test). However, Group 2 showed a statistically significantly lower vitamin D level compared to the insufficiency level of 20ng/mL (P= 0.00; one-sample t-test). Conclusion. Vitamin D may have an important function in lens metabolism. Vitamin D deficiency and cataract development need further extensive researches. [ABSTRACT FROM AUTHOR]

Purpose: Early onset opacification of the lens (cataract) has been observed to be on the rise globally. This study was conducted to determine the various types of presenile cataract and to determine the probable risk factors associated with the occurrence of presenile cataract. Materials and Methods: Patients in the age group of 18–40 years attending the Out-Patient Clinic of the Ophthalmology Department who were found to have presenile cataract were recruited as cases. An equal number of consecutive patients of the same age group were included in the control group. Those who gave consent to participate in the study were interviewed through a preformed questionnaire and underwent a complete ocular examination and set of blood investigations. The type of cataract was noted, data obtained were compiled, and examination and investigations done were documented and analyzed using frequency distribution and Chi-squared test. Results: In total, 90 cases and 90 controls that fulfilled the inclusion criteria were recruited. Most common type of cataract was found to be posterior subcapsular cataract. Presenile cataract was observed to be significantly associated with tobacco intake (P = 0.035), hypercholesterolemia (P = 0.002), fuel exposure (P = 0.004), and lower socioeconomic status (P = <0.001). Conclusions: Tobacco chewing, hypercholesterolemia, and excessive fuel exposure are risk factors for early development of cataract. [ABSTRACT FROM AUTHOR]

Ionizing radiation (IR) damages DNA and other macromolecules, including proteins and lipids. Most cell types can repair DNA damage and cycle continuously their macromolecules as a mechanism to remove defective proteins and lipids. In those cells that lack nuclei and other organelles, such as lens fiber cells and mammalian erythrocytes, IR-induced damage to macromolecules is retained because they cannot be easily replenished. Whilst the life span for an erythrocyte is several months, the life span of a human lens is decades. There is very limited turnover in lens macromolecules, therefore the aging process greatly impacts lens structure and function over its lifetime. The lens is a tissue where biomolecular longevity, lifelong retention of its components and continued growth are integral to its homeostasis. These characteristics make the lens an excellent model to study the contribution of retained macromolecular damage over time. Epidemiological data have revealed a significant association between exposure to IR, the loss of lens optical function and the formation of cataracts (cataractogenesis) later in life. Lifestyle, genetic and environmental factors all contribute to cataractogenesis due to their effect on the aging process. Cataract is an iconic age-related disease in humans. IR is a recognised cause of cataract and the occupational lens dose limit is reduced from 150 to 20 mGy / year averaged over 5 years (ICRP Publication 118). Understanding the effects of low dose IR on the lens and its role in cataractogenesis is therefore very important. So we redefine "cataractogenic load" as a term to account for the combined lifestyle, genetic and environmental processes that increase biomolecular damage to lens macromolecules leading to cataract formation. These processes weaken metabolic defenses, increase post-translational protein modifications, and alter the lipid structure and content of the lens. IR exposure is a significant insult to the lens because of free radical generation and the ensuing oxidative stress. We support the concept that damage caused by IR compounds the aging process by increasing the cataractogenic load, hereby accelerating lens aging and its loss of function. [ABSTRACT FROM AUTHOR]

Cataract is currently the primary cause of blindness worldwide, and one of its main risk factors is solar ultraviolet radiation exposure. According to the localization of lens opacities, three main subtypes of cataract are recognized: nuclear, cortical and posterior subcapsular cataract. One of the main determinants of individual long‐term solar radiation exposure is outdoor work. We systematically reviewed scientific literature from the last 20 years to update the recent development of research on the risk of cataract in outdoor workers and on the specific subtypes involved, also investigating the methods applied to evaluate the occupational risk. A total of 15 studies were included in the review, of which 12 showed a positive association. The studies confirm the relationship of long‐term occupational solar radiation exposure with cortical cataract and give new support for nuclear cataract, although no substantial new data were available to support a relation with the posterior subcapsular subtype. In most of the studies, the exposure assessment was not adequate to support a representative evaluation of the ocular risk; however, outdoor work is clearly a relevant risk factor for cataract. Further research providing a better evaluation of the relation between solar radiation exposure levels and lens damage in workers is needed and aimed to establish adequate occupational exposure limits and better preventive measures, studying also their effectiveness. [ABSTRACT FROM AUTHOR]

This study is the first to report cataract type specific risks in a cohort of Russian Mayak Production Association workers following chronic occupational exposure to ionizing radiation. In this retrospective cohort study, 22,377 workers (females 25.4%) first employed in 1948-1982 were followed up till the end of 2008. All cataract subtypes were significantly dependent on sex, attained age, diabetes mellitus, myopia and glaucoma. For each of posterior subcapsular (PSC), cortical and nuclear cataracts, the risk of cataract incidence significantly linearly increased with increasing radiation dose. Excess relative risk per unit effective dose (ERR/Sv) from external γ-rays based on the linear model was 0.91 [95% confidence intervals (CIs) 0.67, 1.20] for PSC, 0.63 (95% CIs 0.49, 0.76) for cortical, and 0.47 (95% CIs 0.35, 0.60) for nuclear cataracts. For all three types of cataracts, exclusion of an adjustment for neutron dose as well as inclusion of additional adjustments for body mass index and smoking index decreased ERR/Sv of external γ-rays. Inclusion of an additional adjustment for glaucoma, however, modestly increased incidence risks for cortical and nuclear cataracts, but not PSC cataracts. Inclusion of an adjustment for diabetes mellitus decreased ERR/Sv of external γ-rays only for PSC incidence. Both males and females had increased risks for all three types of cataracts, but ERR/Sv was significantly higher in females than in males (p < 0.001), particularly for PSC cataracts. The results suggest that chronic occupational radiation exposure significantly increases risks of PSC, cortical and nuclear cataracts, and that such risks are higher in females than in males. [ABSTRACT FROM AUTHOR]

Purpose/aim of the study: To observe and analyze the weekly changes in morphology and size of vacuoles, so called Wedl cells, in eyes with posterior subcapsular cataract (PSC). Materials and methods: Thirty-six eyes of 36 patients with pronounced PSC were included in this prospective study. High-resolution retroillumination images were taken, and the changes in size and shape of Wedl cells were analyzed at baseline and at 2 and 4 weeks later using dedicated imaging software. Results: In total, 1087 Wedl cells were observed. Within 2 and 4 weeks, 31 and 22 Wedl cells appeared and 13 and 40 Wedl cells disappeared, respectively. Median Wedl cell size at baseline and after 2 and 4 weeks was 4000 µm2(range: 40–212120 µm2), 4080 µm2(range: 40–274520 µm2), and 4160 µm2(range: 40–212200 µm2), respectively. For the absolute size change within 4 weeks, a significant difference was observed (p= 0.045). The median change in absolute solidity within 2 and 4 weeks was 0.01 (range: 0.00–0.19) and 0.02 (range: 0.00–0.53), respectively. Conclusions: Wedl cells undergo morphological changes within a short time period of 4 weeks and even appearance and disappearance of Wedl cells can be observed within weeks. The fact that spontaneous regression occurs may, when properly understood, have some relevance for the development of therapeutical approaches to reverse existing PSC in the future. [ABSTRACT FROM AUTHOR]

Cataract leads to visual impairment. Among different types of cataract, posterior subcapsular cataract (PSC) can develop rapidly and surgery is usually needed. An approach to detect PSC opacities in retro-illumination images is proposed. Watershed and Markov random fields (MRF) method are employed to opacities in anterior retro-illumination images. It results in a mixture of PSC, cortical opacities and noise. Then, information in both anterior and posterior retro-illumination images is utilized. Two features are extracted to identify PSC: mean gradient comparison (MGC) between anterior and posterior retro-illumination images, and spatial location. This is the first time that comparison between anterior and posterior retro-illumination images is proposed and MGC is proposed as the feature of comparison in PSC detection. Experiments show that the sensitivity and specificity of PSC screening is 91.2 and 90.1 %, respectively, based on the 519 pairs of testing images. To the best of our knowledge, it is the best performance reported in automatic detection of PSC. Compared with the methods in the literatures, considerable improvement is achieved when there are large areas of PSC opacities. [ABSTRACT FROM AUTHOR]