Keratoconus is a condition of the eye that affects approximately 1 in 2000 people. The disease leads to a gradual increase in corneal curvature and decrease in visual acuity with consequent impact on quality of life. Collagen cross-linking (CXL) with ultraviolet A (UVA) light and riboflavin (vitamin B2) is a relatively new treatment that has been reported to slow or halt the progression of the disease in its early stages. The objective of this review was to assess whether there is evidence that CXL is an effective and safe treatment for halting the progression of keratoconus compared to no treatment. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 7), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to August 2014), EMBASE (January 1980 to August 2014), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to August 2014), Cumulative Index to Nursing and Allied Health Literature (CINAHL) (1982 to August 2014), OpenGrey (System for Information on Grey Literature in Europe) (www.opengrey.eu/), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organisation International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We used no date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 28 August 2014. We included randomised controlled trials (RCTs) where CXL with UVA light and riboflavin was used to treat people with keratoconus and was compared to no treatment. Two review authors independently screened the search results, assessed trial quality, and extracted data using standard methodological procedures expected by Cochrane. Our primary outcomes were two indicators of progression at 12 months: increase in maximum keratometry of 1.5 dioptres (D) or more and deterioration in uncorrected visual acuity of more than 0.2 logMAR. We included three RCTs conducted in Australia, the United Kingdom, and the United States that enrolled a total of 225 eyes and analysed 219 eyes. The total number of people enrolled was not clear in two of the studies. Only adults were enrolled into these studies. Out of the eyes analysed, 119 had CXL (all using the epithelium-off technique) and 100 served as controls. One of these studies only reported comparative data on review outcomes. All three studies were at high risk for performance bias (lack of masking), detection bias (only one trial attempted to mask outcome assessment), and attrition bias (incomplete follow-up). It was not possible to pool data due to differences in measuring and reporting outcomes. We identified a further three unpublished trials that potentially had enrolled a total of 195 participants.There was limited evidence on the risk of progression. Analysis of the first few participants followed up to one year in one study suggested that eyes given CXL were less likely to have an increase in maximum keratometry of 1.5 D or more at 12 months compared to eyes given no treatment, but the confidence intervals (CI) were wide and compatible with no effect or more progression in the CXL group (risk ratio (RR) 0.12, 95% CI 0.01 to 2.00, 19 eyes). The same study reported the number of eyes with an increase of 2 D or more at 36 months in the whole cohort with a RR of 0.03 favouring CXL (95% CI 0.00 to 0.43, 94 eyes). Another study reported "progression" at 18 months using a different definition; people receiving CXL were less likely to progress, but again the effect was uncertain (RR 0.14, 95% CI 0.01 to 2.61, 44 eyes). We judged this to be very low-quality evidence due to the risk of bias of included studies, imprecision, indirectness and publication bias but noted that the size of the potential effect was large.On average, treated eyes had a less steep cornea (approximately 2 D less steep) (mean difference (MD) -1.92, 95% CI -2.54 to -1.30, 94 eyes, 1 RCT, very low-quality evidence) and better uncorrected visual acuity (approximately 2 lines or 10 letters better) (MD -0.20, 95% CI -0.31 to -0.09, 94 eyes, 1 RCT, very low-quality evidence) at 12 months. None of the studies reported loss of 0.2 logMAR acuity. The data on corneal thickness were inconsistent. There were no data available on quality of life or costs. Adverse effects were not uncommon but mostly transient and of low clinical significance. In one trial, 3 out of 12 participants treated with CXL had an adverse effect including corneal oedema, anterior chamber inflammation, and recurrent corneal erosions. In one trial at 3 years 3 out of 50 participants experienced adverse events including mild diffuse corneal oedema and paracentral infiltrate, peripheral corneal vascularisation, and subepithelial infiltrates and anterior chamber inflammation. No adverse effects were reported in the control groups. The evidence for the use of CXL in the management of keratoconus is limited due the lack of properly conducted RCTs.

To describe the frequency of neovascular age-related macular degeneration (nAMD) in second eyes of patients undergoing ranibizumab therapy in their first eye and to evaluate the patterns of optical coherence tomography (OCT) abnormalities in fellow eyes before nAMD. Patients who developed choroidal neovascularization (CNV) in the second eye while on treatment for the first eye were identified. OCT scans of the second eyes, performed before the onset of CNV, were retrospectively examined and graded. Frequency of second eye involvement was estimated and patterns of progression of OCT abnormalities were described and classified. In all, 65 out of 749 consecutive patients required ranibizumab in their second eye for treatment-naïve nAMD over a 2-year period. The mean interval from commencement of ranibizumab in first eye to conversion in second eye was 12 months (2–35.5 months). There were three patterns of CNV development: group A (12%, n=8) had no OCT abnormalities in the second eye just before developing CNV; group B (38%, n=25) had no abnormalities at baseline but developed OCT changes more than one visit before conversion and group C (50%, n=32) had OCT changes from baseline, which did not progress until just before conversion. Patients with retinal pigment epithelial elevation without sub-retinal fluid on OCT in their fellow eyes have a high risk of progression to require therapy within a 2-year period. An anticipatory approach may be warranted, but a small group with completely normal OCT appearances can still develop lesions between visits.

Purpose. To determine the prevalence, causes, and factors associated with presenting visual impairment and blindness among pensioners. Design. A nationwide cross-sectional study. This study was part of the analysis on data obtained in the pensioners’ medical survey conducted among members of the National Pensioners Association in Ghana. Method. (i) Setting: it was a multicenter study involving thirteen centers throughout Ghana with a center in each regional capital. (ii) Study population: the study involved 4813 pensioners. (iii) Observation procedures: data were captured through the use of questionnaires, physical examinations including eye examinations, and urine and blood sample analysis. (iv) Main outcome measure: presenting visual impairment and blindness (as defined by the WHO ICD-10 classification). Results. The overall prevalence of blindness among pensioners in Ghana was 3.8% (95% CI = 3.2–4.4), while the prevalence of moderate and severe visual impairment was 21.7% (95% CI = 20.5–23.0). The prevalence of blindness was lowest in the 60–65-year-old age group (2.1% (95% CI = 1.3–2.8)) and highest in the above 80-year-old age group (12.2% (95% CI = 6.6–17.8)). Cataract was the leading cause of blindness (62.4%) and moderate and severe visual impairment (55.7%). Factors significantly associated with blindness and visual impairment include educational status, vegetarianism, arthritis, and having proteins in urine. Conclusion. There is a high prevalence of visual impairment and blindness among the pensioners in Ghana. Sadly, the greatest cause was cataract, which is correctable. Increase in formal education status will be important in the prevention of blindness and visual impairment.

Sickle cell retinopathy is a potentially blinding condition that affects young people in the working age group. This review looks at the past, present and future management of sickle cell retinopathy within an African context. After Sickle cell disease was first reported in 1910, some reports from Africa were pivotal in describing the retinal changes associated with the disease. It soon became obvious that there was a varied clinical picture and clinical course. Several landmark studies were carried out in Jamaica to help elucidate the complexities of the disease and outline appropriate clinical management. In most of the developed world, the clinical management of sickle cell disease has improved with concurrent improvement in outcomes. Currently resource constraints in most Sub-Saharan African countries where there is a high burden of disease means that the management of sickle cell retinopathy is fraught with numerous challenges. Future large scale trials in Africa shall hopefully help to better elucidate the mechanisms behind proliferative sickle retinopathy and help in the development of new and improved therapeutic pathways. The use of technology can help immensely in the screening of patients with sickle cell to detect early proliferative changes and if necessary treat accordingly.

Large language models (LLMs) are emerging as powerful tools in healthcare, with a growing role in global health, particularly in low- and middle-income countries (LMICs). This Perspective examines the current progress, challenges and prospects of LLMs in addressing health system disparities and supporting the achievement of the Sustainable Development Goals (SDGs). While high-income countries dominate the development and deployment of LLMs, LMICs face substantial barriers. These include limited digital infrastructure, a scarcity of locally relevant data, regulatory gaps, under-representation of local languages and dialects, and challenges related to privacy and data security. The limited availability of local expertise, capacity building programmes and sustained technical support remains a key barrier to scaling LLMs in LMICs. Nonetheless, case studies highlight how mobile-based LLM applications, hybrid artificial intelligence systems and open-weight models like DeepSeek are enhancing access to care, improving diagnostics and supporting clinical decision-making in resource-limited settings. Key risks include model hallucinations, equity concerns and environmental impacts. These underscore the need for rigorous validation, localized fine-tuning and global governance frameworks. The implementation of LLMs with contextual sensitivity, responsible oversight and codevelopment partnerships is important to avoid perpetuating health inequities. With the right safeguards and strategic investments in capacity building, LLMs have the potential to transform global health by bridging divides in access, augmenting overburdened health workforces, and enabling scalable and cost-effective innovations for the most underserved communities.