Incidence of Visually Impairing Cataracts Among Older Adults in Kenya

AI-based diagnosis of nuclear cataract from slit-lamp videos

In ophthalmology, the availability of many fundus photographs and optical coherence tomography images has spurred consideration of using artificial intelligence (AI) for diagnosing retinal and optic nerve disorders. However, AI application for diagnosing anterior segment eye conditions remains unfeasible due to limited standardized images and analysis models. We addressed this limitation by augmenting the quantity of standardized optical images using a video-recordable slit-lamp device. We then investigated whether our proposed machine learning (ML) AI algorithm could accurately diagnose cataracts from videos recorded with this device. We collected 206,574 cataract frames from 1812 cataract eye videos. Ophthalmologists graded the nuclear cataracts (NUCs) using the cataract grading scale of the World Health Organization. These gradings were used to train and validate an ML algorithm. A validation dataset was used to compare the NUC diagnosis and grading of AI and ophthalmologists. The results of individual cataract gradings were: NUC 0: area under the curve (AUC) = 0.967; NUC 1: AUC = 0.928; NUC 2: AUC = 0.923; and NUC 3: AUC = 0.949. Our ML-based cataract diagnostic model achieved performance comparable to a conventional device, presenting a promising and accurate auto diagnostic AI tool.

Postprocedural Disorders of Eye and Adnexa Admissions Profile

Purpose

The aim of this study was to examine hospitalisation profiles related to postprocedural disorders of eye and adnexa in England and Wales.

Patients and Methods

This was an ecological study using publicly available data extracted from the "Hospital Episode Statistics (HES) database" in England and the "Patient Episode Database for Wales (PEDW)" for the period between April 1999 and April 2020. Diagnostic code for postprocedural disorders of eye and adnexa (H59) was used to identify hospital admission. We used the chi-squared test to assess the difference between the hospital admission rates between 1999 and 2020.

Results

Hospital admission rate decreased by 6.3% [from 4.98 (95% CI 4.79-5.17) in 1999 to 4.67 (95% CI 4.50-4.84) in 2020 per 100,000 persons, trend test, p<0.05]. The most common hospital admissions causes were other postprocedural disorders of eye and adnexa "Chorioretinal scars after surgery for detachment." The age group 75 years and above accounted for 44.3% of the total number of admissions. Hospital admission rate among females decreased by 30.2% [from 5.90 (95% CI 5.61-6.19) in 1999 to 4.12 (95% CI 3.89-4.35) in 2020 per 100,000 persons]. Hospital admission rate among males increased by 30.2% [from 4.02 (95% CI 3.77-4.26) in 1999 to 5.23 (95% CI 4.97-5.49) in 2020 per 100,000 persons].

Conclusion

This study revealed that hospital admission rates for postprocedural disorders of the eye and adnexa decreased over the course of the study period. Eye and adnexa disorders accounted for the preponderance of hospital admissions among the elderly. Further research is required to identify risk factors that can be avoided.

Visually significant cataract and associated factors among older people attending a community ophthalmic service in central Gondar Zone, Northwest Ethiopia: a cross-sectional study

Objective

In this study, we aimed to determine the prevalence of visually significant cataract and associated factors among older people attending community ophthalmic services in the central Gondar Zone, Northwest Ethiopia.

Methods

We conducted a community outreach-based cross-sectional study among adults aged ≥40 years in the central Gondar Zone from 30 May to 15 June 2021. We used systematic random sampling to select study participants. Interviewer-administered questionnaires and ocular examinations were performed and the data recorded. We applied binary logistic regression to identify factors associated with visually significant cataract.

Results

A total of 821 participants were included, with median age 57 years. The prevalence of visually significant cataract was 29.1% (95% CI: 26.1–32.0). Age ≥80 years (adjusted odds ratio [AOR] = 16.9; 95% CI: 7.5–38.4), rural residence (AOR = 1.7; 95% CI: 1.02–2.7), unmarried status (AOR = 1.9; 95% CI: 1.2–3.2), illiteracy (AOR = 2.9; 95% CI: 1.4–6.1), unemployed status (AOR = 1.7; 95% CI: 1.1–2.7), and sunlight exposure ≥5 hours per day (AOR = 1.6; 95% CI: 1.04–2.4) were significantly associated with visually significant cataract.

Conclusion

In this study, visually significant cataract was found to be high, which requires immediate public health intervention.

Comparing the accuracy of new intraocular lens power calculation formulae in short eyes after cataract surgery: a systematic review and meta-analysis

PURPOSE

Calculating the intraocular lens (IOL) power in short eyes for cataract surgery has been a challenge. A meta-analysis was conducted to identify, among several classic and new IOL power calculation formulae, which obtains the best accuracy.

METHODS

All studies aiming at comparing the accuracy of IOL power calculation formulae in short eyes were searched up in the databases of PubMed, EMBASE, Web of Science and the Cochrane library from Jan. 2011 to Mar. 2021. Primary outcomes were the percentages of eyes with a refractive prediction error in ± 0.25D, ± 0.5D and ± 1.0D.

RESULTS

Totally 1,476 eyes from 14 studies were enrolled in comparison of 13 formulae (Barrett Universal II, Castrop, Haigis, Hoffer Q, Holladay1, Holladay2, Kane, Ladas Super Formula, Okulix, Olsen, Pearl-DGS, SRK/T and T2). Pearl-DGS had the highest percentage within ± 0.25D. In the ± 0.5D range, Pearl-DGS obtained the highest percentage again, and it was significantly higher than Barrett Universal II, Haigis, Hoffer Q, Holladay1, Holladay2 and Olsen (P = 0.001, P = 0.02, P = 0.0003, P = 0.01, P = 0.007, P = 0.05, respectively). In the ± 1.0D range, Okulix possessed the highest percentage, and it was significantly higher than Barrett Universal II, Castrop, Hoffer Q and Holladay2 (P = 0.0005, P = 0.03, P = 0.003, P = 0.02, respectively).

CONCLUSION

The new generation formulae, based on artificial intelligence or ray-tracing principle, are more accurate than the convergence formulae. Pearl-DGS and Okulix are the two most accurate formulae in short eyes.

Active-fluidics versus gravity-fluidics system in phacoemulsification for age-related cataract (AGSPC): study protocol for a prospective, randomised, double-blind, controlled clinical trial

INTRODUCTION

The active-fluidics system is a new irrigation system of phacoemulsification that automatically detects and maintains stable intraocular pressure at the set value. This trial is designed to compare the efficacy, visual outcomes, safety and patients' subjective perceptions of cataract surgery with the active-fluidics system and gravity-fluidics system.

METHODS AND ANALYSIS

This trial will recruit 110 patients with age-related cataract at the Chinese People's Liberation Army (PLA) General Hospital (Beijing, China) and they will be randomly assigned to the active-fluidics group and gravity-fluidics group in a ratio of 1:1 to have phacoemulsification. Patients will be followed up at 1 day, 1 week, 1 month and 3 months postoperatively. The primary outcomes are the cumulative dissipated energy and best corrected visual acuity. Secondary outcomes include: estimated fluid usage, U/S time, total aspiration time, intraocular pressure, corneal endothelium parameters, retinal thickness, macular superficial vessel density, pain scores, scores of the Cataract surgery Patient-Reported Outcome Measures Questionnaire and the complication rates. The data will be independently analysed by the statistical team, who will be masked for the allocation information as participants are.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Chinese PLA General Hospital (approval no. S2021-068-01). Informed consent will be obtained from each participant. All the results will be published in peer-reviewed journals and used for scholarly communication or technical guidance. Protocol version 1.0.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR2100044409).

Efficacy, safety and visual outcomes of cataract surgeries performed during blindness prevention programs in different locations in Kenya

PURPOSE

To determine the visual outcomes achieved in terms of efficacy and safety during high-volume cataract surgery programs in different locations in Kenya.

METHODS

Eight hundred eighty-one eyes of 849 patients underwent extracapsular cataract extraction with intraocular lens implantation in a retrospective, observational, consecutive cohort study on patients who underwent cataract surgery in five programs that a Spanish non-governmental organization conducted between 2013 and 2019 for the prevention of blindness in different geographical areas of Kenya: Thika, Athi River, Kissi, Bagavathi, and Nakuru. The programs were carried out by Spanish and Kenyan surgeons working together.

RESULTS

Mean age was 66.81 ± 14.47 years. Fifty-one percent of the operated eyes (447 eyes) were women. 94% of patients belonged to six ethnic groups. The mean uncorrected distance visual acuity (UDVA) before surgery was 1.98 ± 0.98 logMAR (20/2000), which changed to 0.82 ± 0.68 logMAR (20/150) 3 months after surgeries. The corrected distance visual acuity (CDVA) was 0.4 ± 0.53 logMAR (20/50) 3 months after surgery, 77.5% of the patients had good visual outcomes, and 6.3% had poor outcomes. Preoperative UDVAs were significantly different with respect to the different geographical areas (Kruskal-Wallis; p < 0.001). The most common intraoperative complication was posterior capsule rupture (incidence, 4.2%, 37 of 881), and the most serious complication was expulsive hemorrhage (incidence, 0.1%, 1 of 881).

CONCLUSIONS

Cataract programs performed in a middle-income country with the proper technique and standardized protocols of action improved the visual outcome of the patients. Dissimilar baseline status was found in different areas regarding preoperative visual acuities. Training programs of local surgeons should be reinforced.

Evaluation of Nuclear Cataract with Smartphone-Attachable Slit-Lamp Device

Background: Visual impairments and age-related eye diseases need to be detected and treated in a timely manner. However, this is often hampered by lack of appropriate medical equipment. We have invented a portable, recordable, and smartphone-attachable slit-lamp device, called the Smart Eye Camera (SEC). The aim of this study was to compare evaluating nuclear cataract (NUC) between the SEC and the conventional, non-portable slit-lamp microscope. Methods: A total of 128 eyes of 64 Japanese patients (mean age: 73.95 ± 9.28 years; range: 51‒92 years; female: 34) were enrolled. The NUC was classified into four grades (grade 0 to 3) based on three standard photographs of nuclear opacities according to the WHO classification by ophthalmologists. An ophthalmic healthcare assistant (non-ophthalmologist) filmed the eyes in video mode by the SEC and an ophthalmologist graded the NUC. Grade correlation and inter-rater reproducibility were determined. Results: NUC grading by the two approaches correlated significantly (both eyes: r = 0.871 [95%CI: 0.821 to 0.907; p < 0.001]). Inter-rater agreement was high (weighted κ = 0.807 [95%CI: 0.798 to 0.816; p < 0.001]). Conclusions: This study suggests that the SEC is as reliable as the conventional non-portable slit-lamp microscope for evaluating NUC.

Environmental effects of stratospheric ozone depletion, UV radiation and interactions with climate change: UNEP Environmental Effects Assessment Panel, update 2019

This assessment, by the United Nations Environment Programme (UNEP) Environmental Effects Assessment Panel (EEAP), one of three Panels informing the Parties to the Montreal Protocol, provides an update, since our previous extensive assessment (Photochem. Photobiol. Sci., 2019, 18, 595-828), of recent findings of current and projected interactive environmental effects of ultraviolet (UV) radiation, stratospheric ozone, and climate change. These effects include those on human health, air quality, terrestrial and aquatic ecosystems, biogeochemical cycles, and materials used in construction and other services. The present update evaluates further evidence of the consequences of human activity on climate change that are altering the exposure of organisms and ecosystems to UV radiation. This in turn reveals the interactive effects of many climate change factors with UV radiation that have implications for the atmosphere, feedbacks, contaminant fate and transport, organismal responses, and many outdoor materials including plastics, wood, and fabrics. The universal ratification of the Montreal Protocol, signed by 197 countries, has led to the regulation and phase-out of chemicals that deplete the stratospheric ozone layer. Although this treaty has had unprecedented success in protecting the ozone layer, and hence all life on Earth from damaging UV radiation, it is also making a substantial contribution to reducing climate warming because many of the chemicals under this treaty are greenhouse gases.