Colin Cook

Purpose: Monitoring the visual acuity following cataract surgery is used as a measure of the quality of the surgery in blindness prevention programs in middle- and low-income countries. While the day 1 visual acuity is usually available, the (final) visual acuity after several weeks may not be available, as the majority of patients may not return for review. This study was undertaken to ascertain if the early and late visual acuities are correlated and if the day 1 visual acuity can be used to predict the likely final visual acuity. Methods: A retrospective case note review was undertaken of all eyes having cataract surgery over a 6-month period. Results: There was a positive correlation between the day 1 and week 6 visual acuities in both the World Health Organization categories (Spearman coefficient = 0.4666, P = 0.001) and the logMAR visual acuity scores (Spearman coefficient = 0.5425, P = 0.001). Conclusion: In blindness prevention programs in middle- and low-income countries with poor postoperative follow-up where it is not possible to document the final visual acuity in all the operated cases, there is merit in documenting and monitoring the day 1 visual acuity as a quality control measure.

With a global target set at reducing vision loss by 25% by the year 2019, sub-Saharan Africa with an estimated 4.8 million blind persons will require human resources for eye health (HReH) that need to be available, appropriately skilled, supported, and productive. Targets for HReH are useful for planning, monitoring, and resource mobilization, but they need to be updated and informed by evidence of effectiveness and efficiency. Supporting evidence should take into consideration (1) ever-changing disease-specific issues including the epidemiology, the complexity of diagnosis and treatment, and the technology needed for diagnosis and treatment of each condition; (2) the changing demands for vision-related services of an increasingly urbanized population; and (3) interconnected health system issues that affect productivity and quality. The existing targets for HReH and some of the existing strategies such as task shifting of cataract surgery and trichiasis surgery, as well as the scope of eye care interventions for primary eye care workers, will need to be re-evaluated and re-defined against such evidence or supported by new evidence.

Recently there has been a great deal of new population based evidence on visual impairment generated in sub-Saharan Africa (SSA), thanks to the Rapid Assessment of Avoidable Blindness (RAAB) survey methodology. The survey provides information on the magnitude and causes of visual impairment for planning services and measuring their impact on eye health in administrative “districts” of 0.5–5 million people. The survey results describing the quantity and quality of cataract surgeries vary widely between study sites, often with no obvious explanation. The purpose of this study was to examine health system characteristics that may be associated with cataract surgical coverage and outcomes in SSA in order to better understand the determinants of reducing the burden of avoidable blindness due to cataract. This was a descriptive study using secondary and primary data. The outcome variables were collected from existing surveys. Data on potential district level predictor variables were collected through a semi-structured tool using routine data and key informants where appropriate. Once collected the data were coded and analysed using statistical methods including t-tests, ANOVA and the Kruskal-Wallis analysis of variance test. Higher cataract surgical coverage was positively associated with having at least one fixed surgical facility in the area; availability of a dedicated operating theatre; the number of surgeons per million population; and having an eye department manager in the facility. Variables that were associated with better outcomes included having biometry and having an eye department manager in the facility. There are a number of health system factors at the district level that seem to be associated with both cataract surgical coverage and post-operative visual acuity outcomes. This study highlights the needs for better indicators and tools by which to measure and monitor the performance of eye health systems at the district level. It is unlikely that epidemiological data alone is sufficient for planning eye health services within a district and health managers and study coordinators need to consider collecting supplementary information in order to ensure appropriate planning can take place.

Background: South Africa has a low incidence of acute appendicitis, but poor outcomes. However, South African studies on appendicitis focus solely on public hospitals, neglecting those who utilize private facilities. This study aims to compare appendicitis characteristics and outcomes in public and private hospitals in South Africa.Methods: A prospective cohort study was conducted among two public and three private hospitals in the Cape Town metropole, from September 2013 to March 2014. Hospital records, operative notes, and histology results were reviewed for patients undergoing appendectomy for acute appendicitis. Patients were interviewed during their hospitalization and followed up at monthly intervals until normal function was attained.Results: A total of 134 patients were enrolled, with 73 in the public and 61 in the private sector. Education and employment were higher among private sector patients. Public sector patients had a higher rupture rate (30.6 vs 13.2 %, p = 0.023). Times to presentation were not statistically different between the two cohorts. Public sector patients had longer hospital stays (5.3 vs 2.9 days, p = 0.036) and longer return to work times (23.0 vs 12.1 days, p < 0.0001). Although complication rates were similar, complications in public hospitals were more severe.Conclusions: Public sector patients in South Africa with appendicitis have higher rupture rates, worse complications, longer hospital stays, and longer recoveries than private sector patients. Patients with perforation had longer delays in presentation than patients without perforation.

Background: HIV infection is thought to be associated with an increased risk of age-related morbidity and premature aging. Lens density increases with age and may function as a biomarker of aging. The relationship of lens density measurements with clinical and demographic characteristics in HIV-infected individuals in comparison with a matched population of HIV-seronegative individuals was investigated. Methods: Case–control study of 490 adults aged greater than or equal to 30 years composed of 242 HIV-infected adults and 248 age- and sex-matched HIV-seronegative individuals. Lens density was assessed using lens densitometry (Pentacam) imaging. Measurements were divided into quartiles, and comparison of HIV status and HIV-related factors was assessed by multivariate and multinomial logistic regression. Results: The mean age was 41.2 years in HIV-infected adults and 42.3 years in HIV-seronegative individuals (P = 0.14). Of the HIV-infected adults, 88% were receiving antiretroviral therapy (ART) (median duration, 58 months), and within this group, their median CD4 count was 468 cells per microliter and 84% had undetectable viral load. Although adjusted lens densities were similar by HIV serostatus, participants on ART and who had nadir CD4 counts less than 200 cells per microliter had a higher risk of high lens density compared with HIV-seronegative individuals (P trend = 0.04). Lens density was weakly associated with detectable HIV viremia despite ART, but not with current CD4 count. Conclusions: HIV-infected individuals on ART with nadir CD4 counts <200 cells per microliter had increased risk of higher lens density. Lens density may represent a novel biomarker of aging, providing insight into accelerated aging trajectories in HIV infection.

Phaco-emulsification versus manual small-incision cataract surgery in South Africa

To determine if there is a screening test or a combination of screening tests that may be suitable for cataract and glaucoma case detection in Vision 2020 programs in Africa. Design-Screening methods validation study. Setting-Groote Schuur Hospital, Cape Town, South Africa. Subjects-African patients aged 40 years and older with known cataract or with known glaucoma, and accompanying relatives aged 40 years and older with no known eye pathology. Outcome measures-Sensitivity, specificity, positive and negative likelihood ratios, and accuracy of 6 screening tests, used alone and in various combinations. Testing the pinhole visual acuity using a cut point of 6/18 in 1 or both eyes has a sensitivity and specificity greater than 90%, a positive likelihood ratio greater than 10.0, a negative likelihood ratio less than 0.1, and an accuracy greater than 90% for case detection of cataract or glaucoma. Examination of the optic disk with a lens free direct ophthalmoscope using a cut point of 0.7 for the vertical cup:disk ratio combined with testing for an afferent pupil defect has similar values for case detection of glaucoma. These tests may be suitable for use in Vision 2020 programs in Africa.

To obtain an estimate of the magnitude of the problem of glaucoma in sub-Saharan Africa, and to evaluate the existing evidence for including glaucoma as a priority disease in our Vision 2020 programs in Africa. A Pubmed search was carried out using "glaucoma prevalence Africa," "glaucoma presentation Africa," "glaucoma blindness Africa," "glaucoma screening Africa," and "glaucoma treatment Africa" as key words. Most glaucoma in Africa is primary chronic open angle glaucoma, it may occur at an earlier age, it may be associated with a higher intraocular pressure, it may be more rapidly progressive, and it may present late. The prevalence of glaucoma in East, Central, and Southern Africa can be conservatively estimated to be 10,000 people for every 1 million population. This prevalence may be higher in West Africa. The annual incidence of glaucoma can be conservatively estimated to be 400 new cases for every 1 million population. Glaucoma is the second leading cause of blindness after cataract, responsible for up to 30% of blindness. Case detection of glaucoma could be carried out at both the primary and secondary level. Primary trabeculectomy with mitomycin C or beta irradiation adjunct may be a suitable treatment. Cases could be followed up after surgery by mid-level eye care workers, using the intraocular pressure as the indicator for adequacy of control, and using a glaucoma register to identify and trace defaulters. Glaucoma should be included as a priority disease in Vision 2020 programs in Africa.