Cataract Surgical Services Research Articles

Prevalence of blindness and visual impairement in Atakunmosa west local government area of southwestern Nigeria

Blindness survey remains a useful tool for eye care needs assessment. A cross sectional survey of Atakunmosa West Local Government Area, a rural community of southwest Nigeria with no form of eye care facility was carried out. The objective of this study was to define areas of eye care need and develop programme for elimination of avoidable blindness in the region. Multistage cluster sampling technique selected 1248 respondents across all the eleven health districts. Respondents had visual acuity and ocular examination. Blindness was defined as presenting visual acuity (pva) of < 3/60 in the better eye and visual impairment as pva of < 6/18 in the better eye. Out of the 1,248 respondents screened, 14 (1.1%) were blind and 78 (6.3%) were visually impaired. There was an increasing risk of blindness and visual impairment with age; occurring more commonly after 60 years of age. The prevalence of blindness and visual impairment were higher in females although not statistically significant (P = 0.70; 0.46 respectively). Blindness was caused mainly by cataract (57.2%), glaucoma (14.3%) and congenital childhood blindness (14.3%). Cataract (57.7%), glaucoma (16.7%) and uncorrected refractive error (15.4%) were the leading causes of visual impairment. Blindness was avoidable in 85.7% of cases. Qualitative and subsidised cataract surgical and refractive services are needed urgently in this region and therefore, the incorporation of eye health care into the existing primary health care system may ensure programme sustainability.

The surgical management of cataract: barriers, best practices and outcomes

Cataract is the leading cause of blindness in the world. Cataract surgery has been shown by multiple studies to be one of the most cost-effective health interventions, and leads to a dramatic increase in quality of life and productivity for many patients. Though there has been marked improvement in the last several decades, surgical delivery services in developing nations are still suboptimal, and a large backlog in cataract cases continues to grow. To decrease this backlog, barriers to surgery, such as direct and indirect patient costs, geographic access to surgical facilities and surgeons, cultural factors, and patient education, must be addressed. In particular, access to services by women and rural patients needs to be improved. It is clear that extracapsular techniques are cost-effective and lead to better post-operative outcomes than intracapsular cataract extraction with aphakic correction. In addition, monitoring surgical outcomes is essential for improving the quality of surgical services. However, other issues regarding the delivery of cataract surgical services, including the role of average power intraocular lenses and the role of non-physician surgeons, are yet unresolved. Information about the true cost of surgery, including costs of surgeon training, equipment, and patient outreach programs, is needed so that the goal of self-sustaining programs may be obtained.

Cataract prevalence, cataract surgical coverage and barriers to uptake of cataract surgical services in Pakistan: the Pakistan National Blindness and Visual Impairment Survey

Aim:To estimate the prevalence of visual impairment and blindness caused by cataract, the prevalence of aphakia/pseudophakia, cataract surgical coverage (CSC) and to identify barriers to the uptake of cataract services...

Prevalence and causes of blindness and visual impairment in Limbe urban area, South West Province, Cameroon

Aim:To conduct a rapid assessment of cataract surgical services to estimate the prevalence and causes of blindness and visual impairment in members of the population aged ⩾40 years in the...

Cataract Blindness in 4 Regions of Guatemala: Results of a Population-Based Survey

To assess prevalence of visual impairment resulting from cataract and cataract surgical services in 4 departments (provinces) of Guatemala to facilitate further health care planning. Cross-sectional study. Ninety-eight enumeration areas were selected by systematic sampling in 4 departments in southwest Guatemala, with a combined population of 1,339,508 (2002 census). Ninety-eight clusters of 50 persons > or =50 years of age (4900 eligible persons) were selected by random walk, 1 in each selected enumeration area. A total of 4806 persons were examined (coverage, 98.1%): 1808 (37.6%) men and 2998 (62.4%) women. Mean age was 63.7 years. Each eligible participant was interviewed and underwent an assessment of visual acuity and ophthalmic examination to assess lens status. Visual acuity of each eye with available correction and with pinhole correction; lens status; cause of visual impairment in 1 or both eyes; reason(s) why cataract operation had not been performed; and details of previous cataract surgery. Cataract is the major cause of bilateral blindness (66.1%). The adjusted prevalence of bilateral cataract blindness (best-corrected visual acuity [BCVA], <20/400) in people 50 years of age and older was 2.3% (95% confidence interval [CI], 1.8%-3.0%), or an estimated 3726 persons. The cataract surgical coverage was 49% for men and 28% for women. The adjusted prevalence of bilateral cataract and BCVA<20/200 in persons 50 years of age and older was 3.7% (95% CI, 2.9%-4.4%), or an estimated 5887 persons. In this last group, the surgical coverage was 29% (persons) and 19% (eyes). Of all operated eyes, 36% could not see 20/200. Being unaware of cataract (68%), inability to afford the procedure (12%), and fear of the procedure (10%) were mentioned most often as the reason why surgery had not been performed. There is a backlog in unoperated cataract in the survey area that will increase with ageing. Awareness campaigns, reducing cost, improving the outcome of cataract surgery, and expansion of surgical services may help to increase the cataract surgical rate. Women should be offered more cataract surgery. These results will enable health managers to plan effective interventions in line with Vision 2020.

Coverage, utilization and barriers to cataract surgical services in rural South India: Results from a population-based study

To determine the cataract surgical coverage, utilization and barriers to cataract surgery in a rural taluk of south India. A cross-sectional, community-based survey. A house-to-house survey was carried out in 15 villages that were selected by cluster sampling during January to October, 2002. A total of 1505 people aged 50 years and above were tested for visual acuity (VA) and their eyes examined. Cataract surgical coverage was calculated for people and eyes, and for VA levels of <3/60 and <6/60. Information about details of cataract surgery and barriers to cataract surgery were collected using a pre-designed proforma. Cataract surgical coverage was 63% (people) and 51% (eyes) for VA<3/60 compared with 49% (people) and 36% (eyes) for VA<6/60. Of 109 operated eyes, 51.2% of operations were carried out in private hospitals and 33.3% in voluntary/charitable hospitals. Inability to afford the operation (22.9%) and fear of the operation (19.2%) were the main barriers to cataract surgery. The reasons for underutilization of government hospitals are to be investigated. Awareness of low-cost cataract intraocular lens (IOL) non-governmental organization (NGO) surgery and free-of-cost NGO services available in the region needs to be raised. Barriers to cataract surgical services should be addressed by community-based health-education programmes to improve the uptake of existing services.

Prevalence of blindness and its causes among those aged 50 years and above in rural Karnataka, South India

To estimate the prevalence of blindness and its causes among those aged 50 years and above in rural Karnataka. A total of 1505 people aged 50 years and above from 15 villages were examined. The participants were selected through a house-to-house survey by the cluster sampling method. Visual acuity was tested using a modified Snellen's chart, and eyes were examined to ascertain the cause of blindness. The prevalence of blindness was 6.6% (95% confidence interval: 5.3-7.8%). Bilateral cataract was the principal cause of blindness among 78.7% of the blind and 12.1% were operated for cataract. In conclusion, the study area has a high burden of cataract blindness. Cataract surgical services should be made readily accessible and available to this rural population.

Cataract surgery in the last decade at University Teaching Hospital, Ilorin, Nigeria

A retrospective study of all the patients admitted to the eye ward of University of Ilorin Teaching Hospital (UITH) between January 1990 and December 2000 was done to determine the prevalence of cataract among them. The demographic data and possible risk factors for cataract as well as the laterality of the blind eye were recorded for each patient. The diagnosis of cataract was based on the patient's history, visual acuity assessment by Snellen chart and morphological changes on ophthalmoscopy and slit-lamp microscopy. Seven hundred and sixty-two (43.1%) of the admitted patients (1,769) had cataract consisting of 411 males (53.9%) and 351 females (46.1%), giving M: F ratio 1.2:1. Cataract cases accounted for 54.5% of all ocular surgeries (n = 1,398). About 10% were below the age of 16 years. Bilateral cases were 78.9%, unilateral 21.1%. The right and left eye was involved in 13.2% and 7.9% cases respectively. Cataract was most common (76.6%) in patients older than 45 years. Other causes were congenital – 4.3%, trauma – 11.4%, secondary – 1.2% and unspecified causes – 6.4%. Though hospital based, the prevalence of cataract might be a reflection of the situation within the community as several factors might have been responsible for the low uptake of surgery. Cataract surgical services should be more accessible to the people. We are unaware of a similar report from this institution since the inception of the department as a tertiary eye center in 1988. Keywords: cataract, prevalence, Ilorin, Nigeria Nigerian Medical Practitioner Vol. 49(6) 2006: 161-163

Cataract and its surgery in Timor‐Leste

To determine the prevalence of visually significant and unoperated blinding cataract, and the coverage, characteristics and outcome of cataract surgery in Timor-Leste. Based on the World Health Organization Rapid Assessment of Cataract Surgical Services protocol, a population-based cross-sectional survey was conducted in 2005. By two-stage cluster random sampling, 50 clusters of 30 people aged 40 years and older were selected. Each eye with a presenting visual acuity worse than 6/18 and/or a history of cataract surgery was examined. Of the 1470 people enumerated, 96.2% were examined. Of the eyes examined, 11.5% were blind (presenting vision less than 6/60). Cataract caused 66.3% of this, and 40.2% of vision impairment (presenting vision less than 6/18). For those people who were blind (7.7%; presenting vision less than 6/60 in the better eye), cataract was the most frequent cause (76.1%). Cataract surgery had occurred in 2% of participants. Gender and domicile were not associated with cataract blindness or surgery. Cataract Surgical Coverage (6/60) was 16.3% for Eyes and 20.2% for Persons. Surgical outcomes were poor, falling well short of World Health Organization guidelines. Astigmatism and posterior capsule opacity were important contributors to this. Until census data are available, age-gender-domicile correction of sample findings cannot be calculated. In the meantime, it is estimated there are 11 500 cataract blind in Timor-Leste. Long-term, indigenous cataract surgical services need to be capable of significantly increased output. Better surgical outcomes are required to ensure scarce resources are well used. Laser capsulotomy needs to be planned for as surgical numbers increase.

Cataract and its surgery in Papua New Guinea

To determine the prevalence of visually significant cataract, unoperated blinding cataract, and cataract surgery for those aged 50 years and over in Papua New Guinea. Also, to determine the characteristics, rate, coverage and outcome of cataract surgery, and barriers to its uptake. Using the World Health Organization Rapid Assessment of Cataract Surgical Services protocol, a population-based cross-sectional survey was conducted in 2005. By two-stage cluster random sampling, 39 clusters of 30 people were selected. Each eye with a presenting visual acuity worse than 6/18 and/or a history of cataract surgery was examined. Of the 1191 people enumerated, 98.6% were examined. The 50 years and older age-gender-adjusted prevalence of cataract-induced vision impairment (presenting acuity less than 6/18 in the better eye) was 7.4% (95% confidence interval [CI]: 6.4, 10.2, design effect [deff] = 1.3). That for cataract-caused functional blindness (presenting acuity less than 6/60 in the better eye) was 6.4% (95% CI: 5.1, 7.3, deff = 1.1). The latter was not associated with gender (P = 0.6). For the sample, Cataract Surgical Coverage at 6/60 was 34.5% for Eyes and 45.3% for Persons. The Cataract Surgical Rate for Papua New Guinea was less than 500 per million population per year. The age-gender-adjusted prevalence of those having had cataract surgery was 8.3% (95% CI: 6.6, 9.8, deff = 1.3). Vision outcomes of surgery did not meet World Health Organization guidelines. Lack of awareness was the most common reason for not seeking and undergoing surgery. Increasing the quantity and quality of cataract surgery need to be priorities for Papua New Guinea eye care services.

Visual Outcomes of Cataract Surgery in a Rural Population of South India: Results from a Population-Based Survey

We aimed to assess the outcomes of cataract surgery in a rural population of south India. A house-to-house survey was carried out in 15 villages. Out of the 156 eyes operated on for cataract, the outcome was good, borderline and poor in 49.3%, 35.2% and 14.1% of the eyes respectively. There is a need to focus on the quality of cataract surgical services rather than just the number of cataract surgeries to reduce the burden of cataract blindness.

Blindness and vision impairment in the elderly of Papua New Guinea

To estimate the magnitude and causes of blindness and vision impairment in Papua New Guinea for service delivery planning and ophthalmic education development. Using the World Health Organization standardized Rapid Assessment of Cataract Surgical Services protocol, a population-based cross-sectional survey was conducted in 2005. By systematic, two-stage cluster random sampling, 39 clusters each of 30 people aged 50 years and over were selected from urban and rural locations. A cause of vision loss was determined for each eye with a presenting visual acuity worse than 6/18. Of the 1191 people enumerated, 1174 were examined (98.6%). The 50 years and older age-gender adjusted prevalence of vision impairment (presenting visual acuity less than 6/18 in the better eye) was 29.2% (95% Confidence Interval [CI]: 27.6, 35.1, Design Effect [deff] = 2.3). That of functional blindness (presenting visual acuity less than 6/60 in the better eye) was 8.9% (95% CI: 8.4, 12.0, deff = 1.2), and of World Health Organization blindness (but presenting, rather than best corrected, visual acuity of less than 3/60 in the better eye) was 3.9% (95% CI: 3.4, 6.1, deff = 1.0). Uncorrected refractive error (13.1%, 95% CI: 11.3, 15.1, deff = 1.2) and cataract (7.4%, 95% CI: 6.4, 10.2, deff = 1.3) were leading causes of vision impairment, age-gender adjusted. Cataract was the most common (age-gender adjusted 6.4%, 95% CI: 5.1, 7.3, deff = 1.1) cause of functional blindness. On bivariate analysis, increasing age (P < 0.001), illiteracy (P < 0.001) and unemployment (P < 0.001) were associated with functional blindness. Gender was not. The identification and treatment of refractive error and cataract need to be priorities for eye health services in Papua New Guinea if the burden of vision impairment and blindness is to be diminished. The education of community and hospital eye care providers, whether medical, nursing or other cadres, must emphasize these. Eye care services must be structured and provided to allow and encourage accessibility and uptake, with satisfactory treatment outcomes for these conditions.

Rapid Assessment of Visual Impairment Due to Cataract and Cataract Surgical Services in Urban Argentina

Aim: To present results of a rapid assessment on visual impairment due to cataract and on cataract surgical services in the Northwestern districts of Buenos Aires, Argentina. These results will enable health managers to plan effective interventions in this area in line with VISION 2020. Methods: One hundred fifteen clusters of 40 persons of 50 years and older in each cluster (4600 eligible persons) were selected by systematic sampling from the Northwestern districts of Buenos Aires, Argentina. This area consists of 10 districts with a total population of 2,716,573 (2001 census), from whom 4302 persons were examined (coverage 93.5%). The visual acuity was measured with a tumbling E-chart and the lens status with distant direct ophthalmoscopy. Results: Cataract is the major cause of bilateral blindness (54.2%). The age and sex adjusted prevalence of bilateral cataract blindness (presenting VA < 20/400) in people of 50 years and older was 0.5% (95% CI: 0.4–0.8%), an estimated number of 2,985 persons. The cataract surgical coverage at this level was 70% for males and 78% for females. The prevalence of bilateral cataract and VA < 20/200 in persons of 50 years and older was 0.8% (95% CI: 0.6–1.1), an estimated 4,705 persons. In this last group, the surgical coverage was 66% (persons) and 57% (eyes). Of all operated eyes, 10% could not see 20/200. ‘Cannot afford’ (32%), ‘unaware of cataract’ (21%) and ‘contraindication for surgery’ (18%) were mentioned most as reason why surgery had not been done. Conclusion: The cataract problem is getting under control in this area. Coverage indicators are fairly high, and the outcome data better than in other studies. The cataract surgical rate could be raised further by awareness campaigns and by making cataract surgery more affordable.

Rapid assessment of cataract surgical services in age group 50 years and above in Lower Dir District Malakand, Pakistan.

To assess the rapid assessment of cataract blindness and surgical services in age group 50 years and above. A cross-sectional survey. This survey was conducted in District Lower Dir, Malakand Division, NWFP, Pakistan, from March 9-23, 2003. A community-based survey was carried out with systematic cluster random sampling. The survey was preceded by a pilot study in which the proforma and operational methods were field-tested and refined. One thousand, one hundred and fifty eligible adults of 50 years and older were selected by systematic random sampling from the whole lower Dir district of Malakand, Pakistan. A total of 1076 subjects (93.6%) were examined. The visual acuity of each eye was assessed using tumble Snellen's E Card method at 6 and 3 meters. Any subject having visual acuity <3/60 with or without obvious lens opacity or with aphakia (removal of lens) or pseudophakia (removal of cataract lens and implantation of artificial lens) was examined in detail. The surgical services were assessed by measuring the prevalence of pseudophakia, surgical outcome of visual acuity and also the effect of place of surgery on outcome. Prevalence of total bilateral blindness was 2.6%, and unilateral blindness 2.46%. Total prevalence of aphakia was 2.4%, which was almost equal in both sexes, male 2.3% and female 2.4%. Prevalence of unilateral aphakia was 0.3 % in females being slightly higher than males, 0.16 %. The prevalence of bilateral aphakia was 2.2% and 2% in males and females respectively. Prevalence of total pseudophakic eyes was 2.74%. Surgical outcome showed good, borderline and poor visual acuity of 40.5%, 22% and 14.3% respectively. Surgical outcome was also seemed to be better in private hospitals as compared to field camps. It is concluded that to reduce the prevalence of blindness there was a need to improve the quality of services in mobile camps and fixed facilities. At the same time the visual outcome of surgery could be improved by expanding the number of Intraocular lens procedures and routine monitoring of cataract outcome.

Cataract surgery: reducing risk through better practice

PurposeA guideline to the practice of cataract surgery was produced in 2004 by the Royal College of Ophthalmologists. This complemented a guideline to best practice produced in 2000 by the NHS Executive. This paper reviews the guidance given by these documents and examines their clinical governance and risk management advice and usefulness.Design/methodology/approachThe guideline is critiqued in terms of its usefulness to clinicians and health‐care managers. Recent research on the consenting process for cataract surgery is used as a benchmark of best practice and compared with the guideline's recommended methods. The medico‐legal caseload experience of The Medical Protection Society (the authors' institution) is used to discuss areas of concern relating to risk management in cataract surgery of interest to clinicians and managers.FindingsThe guideline is felt to be a useful, well‐produced and recommended resource for clinicians and managers with clinical governance responsibilities for cataract surgery services. There was felt to be scope to improve some of the guidance on reporting adverse events following cataract surgery to patients.Practical implicationsThis paper will help to inform the gaining of consent for cataract surgery in the light of the latest research in this area, and help train staff in this task.Originality/valueThis paper will be of value to clinicians and managers with responsibility for cataract surgical services. It should help to inform how they set up, review and audit their practice in this area and be useful for staff training. It highlights areas of the guideline which may be of relevance to those without time to read the whole guideline.

Phacomorphic Glaucoma in Gambians

Aims: (i) To assess the uptake of cataract surgical services in the Gambia in a simple way, using the incidence of Phacomorphic glaucoma. (ii) To review the cases of phacomophic glaucoma seen in the Gambia over a one-year period. (iii) To update us on the systematic approach to the treatment of early phacomorphic glaucoma. Report: Four cases of phacomorphic glaucoma (with no previous history or signs of trauma, uveitis or any other ocular or systematic pathology that could explain the development of the glaucoma apart from cataract) seen over a one-year period in Royal Victoria Hospital, Banjul, the tertiary unit of the Gambian Eye Care Programme, were identified and analysed for age, sex, symptoms/signs, duration and treatment. There were 3 females and 1 male aged between 50 and 71 years. All but one presented with pain and blurred vision of≤3 week duration. Visual acuity at presentation was ≤PL in all patients and all remained blind (visual acuity Conclusions: i. Generally, the uptake of cataract surgical services in the Gambia is good. ii. In spite of the effectiveness of the cataract surgical services of the Gambian Eye Care programme, those in dire need of cataract surgery have not come in contact with the available services. Key words: Phacomorphic glaucoma; lens intumescence. (J College Med: 2003 8(1): 30-32)

Cataract blindness in Chakwal District, Pakistan: Results of a survey

AIM To present the results of a rapid assessment of cataract surgical services in Chakwal District, Pakistan. METHODS 40 clusters of 40 persons of 50 years and older (1600 eligible persons) were selected by systematic random sampling from the entire Chakwal district. A total of 1505 persons were examined (coverage 94%). RESULTS Cataract is the major cause of bilateral blindness (46.5%). The age and sex adjusted prevalence of bilateral cataract blindness (VA < 3/60) in people of 50 years and older was 2.0% (95% CI: 1.2–3.2%), with a cataract surgical coverage of 92% for males and 73% for females, a significant difference. The prevalence of bilateral cataract and VA < 6/60 in persons of 50 years and older was 5.1% (95% CI: 3.6–6.9), an estimated total of 8833 persons. In this last group, the surgical coverage was 66% (persons) and 50% (eyes). Of the patients operated with IOL implantation, 12% could not see 6/60, while 36% of those operated without IOL could not see 6/60. ‘No services’ (18%) and ‘cannot afford’ (18%) were mentioned most as reasons why surgery had not been done, followed by ‘no information’ (13%), ‘waiting for maturity’ (12%) and ‘old age, no need for surgery’ (12%). CONCLUSION The number of cataract operations in Chakwal District can be increased by reducing the threshold for cataract surgery to VA < 6/60 or less. A special approach to operate more females may be required. Results from this survey can be used for a planning exercise to optimize eye care services in the district. Sustained efforts have to be made to increase the number of IOL surgeries, through making IOL surgery available locally at an affordable cost.

Cataract blindness in Paraguay – results of a national survey

PURPOSE To estimate the burden of visual loss and blindness due to cataract in people aged 50 years and over in Paraguay. METHODS Forty clusters of 60 persons each who were 50 years and older (2400 eligible persons) were selected by systematic random sampling from the entire population of Paraguay.A total of 2136 persons were examined (89% coverage). RESULTS For the population 50 years and over, the age- and gender- adjusted prevalence of bilateral blindness (VA < 3/60 with available correction) was 3.14% (95% CI: 2.2–4.4). The adjusted prevalence of bilateral cataract blindness (VA < 3/60) was 2.01% (95% CI: 1.3–3.0), making cataract the major cause of bilateral blindness in this age group (64%). The adjusted prevalence of bilateral severe visual impairment (VA < 6/60 with available correction) was 5.17% (95% CI: 3.9–6.7) and the adjusted prevalence of severe visual impairment due to bilateral cataract (VA < 6/60) was 3.09% (95% CI: 2.2–4.3). The cataract surgical coverage (persons) was 44% for bilaterally blind persons with VA < 3/60; 36% for persons with bilateral VA < 6/60; and 28% for any eye with VA < 6/60 due to cataract. With IOL implantation, 77% of the operated eyes could see 6/18, against 46% of the non-IOLs (p < 0.005), a significant better outcome. CONCLUSIONS There is a need to increase the cataract surgical coverage in Paraguay. The number of eye surgeons is adequate but the accessibility of cataract surgical services in rural areas and the affordability of surgery to large sections of society are major constraints.

Prevalence of lens opacity in Chinese residents of Singapore: the tanjong pagar survey

Objective To determine the prevalence of lens opacity among Chinese residents of Singapore. Design Population-based, cross-sectional survey. Participants Chinese men and women aged 40 years or more in Singapore. Methods A stratified, clustered, random sampling method, with more weights given to the older age groups, was used to initially select 2000 Chinese persons aged 40 to 79 years from the 1996 electoral register in the Tanjong Pagar district in Singapore. Eligible subjects (n = 1717) were invited for a comprehensive ocular examination at a centralized clinic, after which nonrespondents were examined in their homes with portable instruments. Main outcome measures Lens opacity, as determined clinically at the slit lamp using a modification of the Lens Opacity Classification System III. Prevalence rates were age adjusted to the 1997 Singapore census population. Results Of the 1232 persons examined (71.8%), 1206 (70.2%) provided lens data for this analysis. The age-adjusted prevalence of any cataract surgery was 5.1% (95% confidence interval [CI], 3.6, 6.5), with similar rates between men and women. The age-adjusted prevalence of specific types of lens opacity was 22.6% (95% CI, 19.8, 25.4) for any nuclear opacity, 23.9% (95% CI, 21.0, 26.8) for any cortical opacity, and 7.0% (95% CI, 5.3, 8.8) for any posterior subcapsular opacity. The overall age-adjusted prevalence of any cataract or cataract surgery was 34.7% (95% CI, 31.5, 38.0), increasing from 7.0% in those 40 to 49 years and to 94.3% in those 70 years and older ( P < 0.001, test for trend for age). When the prevalence of distinct types of lens opacity in an eye was considered, the most common was mixed (age-adjusted prevalence, 11.5%, based on right eye data), followed by nuclear only (9.7%), cortical only (8.3%), and posterior subcapsular only (0.6%). For all cataract types, the prevalence was similar in men and women and was higher in persons examined at their homes than in those examined at the study clinic. Conclusions These population-based data suggest that cataract is common among adult Chinese residents in Singapore, despite ready access to cataract surgical services. Persons accepting the offer of free eye examinations were less likely to have cataract than those who did not take up this offer.

Cataract in the 21st Century: lessons from previous epidemiologic research

Background: Cataract surgery is currently the most commonly performed ophthalmic procedure in Australia. The purpose of this paper is to review Australian data on cataract prevalence and risk factors and to project potential future demand for cataract services.Methods: Age‐ and gender‐specific cataract prevalence data from the Melbourne Visual Impairment Project (VIP) and the Blue Mountains Eye Study (BMES) were applied to population estimates from the Australian Bureau of Statistics. Published cataract risk factor data from the two studies were reviewed.Results: Although the projected number of cataracts varies substantially based on the definition used, the relative number of cataracts will double over the next 50 years due to the aging of the population. Risk factors for cortical cataract identified in both the VIP and the BMES included female gender, sunlight exposure and myopia. Concord‐ ant findings for nuclear cataract included female gender, brown irides, cigarette smoking and myopia. The only risk factor for posterior subcapsular cataract (PSC) that was identified in both studies was myopia. Some of the discrepant findings between the two studies included alcohol intake, diabetes and medication use.Discussion: These data suggest that supply and demand for cataract surgery must be considered and managed to maintain the current level of cataract surgery delivery as the number of people with cataract increases at a proportionately greater rate than the total population. The supply of cataract surgical services could be increased through an increase in the number of ophthalmologists, an increase in the efficiency with which cataract surgical services are delivered, or improved technology. The demand for cataract surgery could be decreased through the implementation of effective primary prevention strategies, although successful strategies are currently unknown and/or untested. Given our current state of knowledge about cataract, it seems most feasible immediately to alter the health service delivery side of the equation to reduce the public health burden of cataract.