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C A McCarty

Publications and source records attributed to C A McCarty.

At least 91 records · Page 5Linked to original sources
PubMed1999

Comparison of clinical and digital assessment of nuclear optical density.

To compare the standardised Nidek EAS-1000 densitometric analysis of the lens with clinical assessment of the nucleus at an early stage of cataract development, 1,200 eyes of 1,204 participants of the VECAT study were assessed at the baseline using both subjective and objective lens grading. Standardisation of the automatic slit image analysis was achieved using a custom-designed EAS-1000 Software version 3.01c. Among 6 measurements of nuclear optical density, the mean pixel luminescence of integrated anterior nuclear density correlated best with clinical assessment (R = 0.662, p < 0.001). Variance components that interfere with the assessment are defined.

Aged↗
PubMed1999

Culture, coping, and context: primary and secondary control among Thai and American youth.

Do cultural values and traditions influence the development of coping styles ? To address this question, we compared self-reports of coping by 6-14-year-olds in Thailand and the U.S. One hundred and forty-one children were interviewed about six common stressors: separation from a friend, injection in a doctor's office, adult anger, peer animosity, school failure, and physical injury. Children's self-reported coping methods were coded as overt or covert. Coping goals were coded as reflecting primary control (attempts to influence objective conditions), secondary control (attempts to adjust oneself to objective conditions), or relinquished control. Although findings revealed numerous cross-national similarities, there were also multiple main and interaction effects involving culture, suggesting that sociocultural context may be critical to our understanding of child coping. Consistent with literature on Thai culture, Thai children reported more than twice as much covert coping as American children for stressors involving adult authority figures (i.e. adult anger, injection in doctor's office). Thai children also reported more secondary control goals than Americans when coping with separation, but American children were five times as likely as Thais to adopt secondary control goals for coping with injury. The findings support a model of coping development in which culture and stressor characteristics interact, with societal differences most likely to be found in situations where culture-specific norms become salient.

Adaptation, Psychological↗
PubMed1999

Refractive errors in an urban population in Southern India: the Andhra Pradesh Eye Disease Study.

PURPOSE: To assess the prevalence, distribution, and demographic associations of refractive error in an urban population in southern India. METHODS: Two thousand five hundred twenty-two subjects of all ages, representative of the Hyderabad population, were examined in the population-based Andhra Pradesh Eye Disease Study. Objective and subjective refraction was attempted on subjects >15 years of age with presenting distance and/or near visual acuity worse than 20/20 in either eye. Refraction under cycloplegia was attempted on all subjects < or =15 years of age. Spherical equivalent >0.50 D in the worse eye was considered as refractive error. Data on objective refraction under cycloplegia were analyzed for subjects < or =15 years and on subjective refraction were analyzed for subjects >15 years of age. RESULTS: Data on refractive error were available for 2,321 (92.0%) subjects. In subjects < or =15 years of age, age-gender-adjusted prevalence of myopia was 4.44% (95% confidence interval [CI], 2.14%-6.75%), which was higher in those 10 to 15 years of age (odds ratio, 2.75; 95% CI, 1.25-6.02), of hyperopia 59.37% (95% CI, 44.65%-74.09%), and of astigmatism 6.93% (95% CI, 4.90%-8.97%). In subjects >15 years of age, age-gender-adjusted prevalence of myopia was 19.39% (95% CI, 16.54%-22.24%), of hyperopia 9.83% (95% CI, 6.21%-13.45%), and of astigmatism 12.94% (95% CI, 10.80%-15.07%). With multivariate analysis, myopia was significantly higher in subjects with Lens Opacity Classification System HI nuclear cataract grade > or =3.5 (odds ratio, 9.10; 95% CI, 5.15-16.09), and in subjects with education of class 11 or higher (odds ratio, 1.80; 95% CI, 1.18-2.74); hyperopia was significantly higher in subjects > or =30 years of age compared with those 16 to 29 years of age (odds ratio, 37.26; 95% CI, 11.84-117.19), in females (odds ratio, 1.86; 95% CI, 1.33-2.61), and in subjects belonging to middle and upper socioeconomic strata (odds ratio, 2.10; 95% CI, 1.09-4.03); and astigmatism was significantly higher in subjects > or =40 years of age (odds ratio, 3.00; 95% CI, 2.23- 4.03) and in those with education of college level or higher (odds ratio, 1.73; 95% CI, 1.07-2.81). CONCLUSIONS: These population-based data on distribution and demographic associations of refractive error could enable planning of eye-care services to reduce visual impairment caused by refractive error. If these data are extrapolated to the 255 million urban population of India, among those >15 years of age an estimated 30 million people would have myopia, 15.2 million hyperopia, and 4.1 million astigmatism not concurrent with myopia or hyperopia; in addition, based on refraction under cycloplegia, 4.4 million children would have myopia and 2.5 million astigmatism not concurrent with myopia or hyperopia.

Adolescent↗
PubMed1998

Is current eye-care-policy focus almost exclusively on cataract adequate to deal with blindness in India?

BACKGROUND: India's National Programme for Control of Blindness focuses almost exclusively on cataract, based on a national survey done in the 1980s which reported that cataract caused 80% of the blindness in India. No current population-based data on the causes of blindness in India are available. We assessed the rate and causes of blindness in an urban population in southern India. METHODS: We selected 2954 participants by stratified, random, cluster, systematic sampling from Hyderabad city. Eligible participants were interviewed and given a detailed ocular assessment, including visual acuity, refraction, slitlamp biomicroscopy, applanation intraocular pressure, gonioscopy, dilatation, grading of cataract, stereoscopic fundus assessment, and automated-threshold visual fields. FINDINGS: 2522 participants, including 1399 aged 30 years or more, were assessed. 49 participants (all aged > or =30 years) were blind (presenting distance visual acuity <6/60 or central visual field <200 in the better eye). The rate of blindness among those aged 30 years or more, adjusted for age and sex, was 3.08% ([95% CI 1.95-4.21]). Causes included cataract (29.7%), retinal disease (17.1%), corneal disease (15.4%), refractive error (12.5%), glaucoma (12.1%), and optic atrophy (11.0%). 15.7% of the blindness caused by visual-field constriction would have been missed without visual-field examination. Also without visual-field and detailed dilated-fundus assessments, blindness attributed to cataract would have been overestimated by up to 75.8%. If the use of cataract surgery in this urban population was half that found in this study, which simulates the situation in rural India, cataract would have caused 51.8% (39.4-64.2) of blindness, significantly less than the 80% accepted by current policy. INTERPRETATION: Much of the blindness in this Indian population was due to non-cataract causes. The previous national survey did not include detailed dilated-fundus assessment and visual-field examination which could have led to overestimation of cataract as a cause of blindness in India. Policy-makers in India should encourage well-designed population-based epidemiological studies from which to develop a comprehensive long-term policy on blindness in addition to dealing with cataract.

Adult↗
PubMed1998

The prevalence of glaucoma in the Melbourne Visual Impairment Project.

PURPOSE: The purpose of the study was to determine the prevalence of glaucoma in Melbourne, Australia. METHODS: All subjects were participants in the Melbourne Visual Impairment Project (Melbourne VIP), a population-based prevalence study of eye disease that included residential and nursing home populations. Each participant underwent a standardized eye examination, which included a Humphrey Visual Field test, applanation tonometry, fundus examination including fundal photographs, and a medical history interview. Glaucoma status was determined by a masked assessment and consensus adjudication of visual fields, optic disc photographs, intraocular pressure, and glaucoma history. RESULTS: A total of 3271 persons (83% response rate) participated in the residential Melbourne VIP. The overall prevalence rate of definite primary open-angle glaucoma in the residential population was 1.7% (95% confidence limits = 1.21, 2.21). Of these, 50% had not been diagnosed previously. Only two persons (0.1%) had primary angle-closure glaucoma and six persons (0.2%) had secondary glaucoma. The prevalence of glaucoma increased steadily with age from 0.1% at ages 40 to 49 years to 9.7% in persons aged 80 to 89 years. There was no relationship with gender. The authors examined 403 (90.2% response rate) nursing home residents. The age standardized rate for this component was 2.36% (95% confidence limits = 0, 4.88). CONCLUSION: The rate of glaucoma in Melbourne rises significantly with age. With only half of patients being diagnosed, glaucoma is a major eye health problem and will become increasingly important as the population ages.

Adult↗
PubMed1998

The epidemiology of dry eye in Melbourne, Australia.

OBJECTIVE: To describe the epidemiology of dry eye in the adult population of Melbourne, Australia. DESIGN: A cross-sectional prevalence study. PARTICIPANTS: Participants were recruited by a household census from two of nine clusters of the Melbourne Visual Impairment Project, a population-based study of age-related eye disease in the 40 and older age group of Melbourne, Australia. Nine hundred and twenty-six (82.3% of eligible) people participated; 433 (46.8%) were male. They ranged in age from 40 to 97 years, with a mean of 59.2 years. MAIN OUTCOME MEASURES: Self-reported symptoms of dry eye were elicited by an interviewer-administered questionnaire. Four objective assessments of dry eye were made: Schirmer's test, tear film breakup time, rose bengal staining, and fluorescein corneal staining. A standardized clinical slit-lamp examination was performed on all participants. Dry eye for the individual signs or symptoms was defined as: rose bengal > 3, Schirmers < 8, tear film breakup time < 8, > 1/3 fluorescein staining, and severe symptoms (3 on a scale of 0 to 3). RESULTS: Dry eye was diagnosed as follows: 10.8% by rose bengal, 16.3% by Schirmer's test, 8.6% by tear film breakup time, 1.5% by fluorescein staining, 7.4% with two or more signs, and 5.5% with any severe symptom not attributed to hay fever. Women were more likely to report severe symptoms of dry eye (odds ratio [OR] = 1.85; 95% confidence limits [CL] = 1.01, 3.41). Risk factors for two or more signs of dry eye include age (OR = 1.04; 95% CL = 1.01, 1.06), and self-report of arthritis (OR = 3.27; 95% CL = 1.74, 6.17). These results were not changed after excluding the 21 people (2.27%) who wore contact lenses. CONCLUSIONS: These are the first reported population-based data of dry eye in Australia. The prevalence of dry eye varies by sign and symptom.

Adult↗
PubMed1998

Evaluation of axis alignment system for correction of myopic astigmatism with the excimer laser.

PURPOSE: To evaluate the efficacy of in situ axis alignment for the treatment of myopic astigmatism with an excimer laser. METHODS: In this prospective clinical trial, 71 eyes with stable astigmatism of -1.00 to -6.00 diopters (D) with or without stable myopia of up to 10.00 D were randomized to receive excimer treatment of their astigmatic component aligned to the axis determined by subjective refraction (control group) or to have the alignment verified and altered is necessary by in situ alignment (axis alignment group). A VISX Twenty-Twenty excimer laser was used for the treatment. Patients were followed for 6 months. RESULTS: In 85% of eyes in the axis alignment group, the axis of cylinder was different from that calculated by routine refraction. Pretreatment mean cylinder was -1.81 D +/- 0.91 (SD) in the axis alignment group and -1.75 +/- 0.60 D in the control group. At 6 months, an undercorrection of cylinder was seen in both groups; the mean residual cylinder was -0.70 +2- 0.56 D in the axis alignment group and -0.59 +/- 0.50 D in the control group. More than 80% of all eyes were within +/- 1.00 D of plano and achieved an uncorrected visual acuity of 6/12 or better. A loss of two or more lines of best corrected visual acuity was recorded in three eyes. CONCLUSION: The in situ alignment technique did not produce better results of photoastigmatic refractive keratectomy than the routine axis alignment technique.

Adult↗
PubMed1998

Excimer laser correction of astigmatism with multipass/multizone treatment. The Melbourne Excimer Laser Group.

PURPOSE: To evaluate the accuracy of excimer laser correction of myopic astigmatism by multipass/multizone photoastigmatic refractive keratectomy (PARK). SETTING: Tertiary referral ophthalmic hospital with an associated private laser facility. METHODS: This study comprised a consecutive series of 332 eyes of 289 patients who were followed for 6 months. All patients were 18 years or older, had stable myopic astigmatism (up to a -19.0 diopters [D] spherical equivalent [SE] at the spectacle plane), and had a best corrected visual acuity of at least 20/60 in both eyes. All eyes were treated with a VISX Twenty-Twenty excimer laser. The correction was divided between ablation zones using a multipass/multizone treatment paradigm based on the amount of myopia and astigmatism. Patients were examined 1 week, and 1, 3, and 6 months after surgery. RESULTS: Analysis of the mean percentage of spherical correction across the range of myopic preoperative SEs treated demonstrated 90% correction for most amounts of myopic astigmatism. Eyes with low myopia (mean preoperative SE < or = -5.0 D) treated with < or = -1.0 diopter cylinder (DC) of astigmatism achieved a mean percentage of spherical correction of 91% versus 93% in eyes with high myopia (> -5.0 D mean preoperative SE). Eyes with low myopia treated with > -1.0 DC of astigmatism achieved a mean percentage spherical correction of 90% versus 89% in eyes with high myopia. The differences between the two groups were not statistically significant. Patients with high relative cylinder (> 80% of total sphere treated) achieved comparable results. Analysis of the astigmatic component of the treatment, independent of the spherical result, showed a trend toward overcorrection in the high myopia group with less than -1.0 DC and a mean astigmatic correction of 89 and 98%, respectively, in the low and high myopic astigmatism groups. The mean angle of error was +2.0 degrees. CONCLUSION: Multipass/multizone PARK for myopic astigmatism demonstrated a high degree of predictability and stability with desirable results for low and high levels of astigmatism across the range of myopic astigmatism treated by surface ablation.

Adult↗
PubMed1998

Methods for the Hong Kong Vision Study: a pilot assessment of visual impairment in adults.

INTRODUCTION: The Hong Kong Vision Study (HKVS) was a pilot study to collect data on the prevalence of eye diseases and risk factors in Hong Kong using methodology comparable to that developed in America and Australia. AIM: The main goal was: to evaluate the application of the methodology in a different culture and language; and to determine the prevalence and risk factors of eye diseases in order to design a larger study of an ethnic Chinese population. METHOD: This study was patterned after the Melbourne Visual Impairment Project using the Chinese language in data collection and examinations. CONCLUSION: Well-designed methodology is transferable to different cultures, languages and continents. Use of similar methodology will enable better comparisons and analyses to be made from population-based data.

Adult↗
PubMed1998

Patterns of glaucoma medication use in urban and rural Victoria.

PURPOSE: The purpose of the present study was to describe patterns of glaucoma medication use among people who self-report a history of glaucoma in a population-based study of age-related eye disease. METHODS: The present study was comprised of a population-based cluster stratified sample of 5000 Victorians aged 40 years and older. Participants completed an interview regarding demographic characteristics, medical history and use of medications. Participants also completed orthoptic and dilated fundus examinations, including measurement of intra-occular pressure (IOP) and visual fields. Glaucoma history and use of glaucoma medication was self reported. Glaucoma disease status was confirmed by a specialist consensus group. RESULTS: The most common glaucoma medications used were beta-adrenoceptor blocking agents (63%), followed by sympathomimetics (18%) and cholinergic agents (16%). There were no differences in glaucoma medication use by gender, age, years since diagnosis, rural or urban residence or a history of glaucoma surgery. Among participants using medication, 16.1% exceeded 21 mmHg IOP. CONCLUSION: The high prevalence of the use of beta-adrenoceptor blocking agent medication reflects the shift from the use of pilocarpine over the past 20 years. The prevalence of IOP greater than 21 mmHg highlights the difficulty in managing high IOP.

Adrenergic beta-Antagonists↗
PubMed1998

Impact of vision impairment on functioning.

PURPOSE: The aim of the present study was to determine the impact of vision loss on the activities of adults. METHODS: Focus groups were conducted that were either disease specific, such as for people with age-related macular degeneration, diabetic retinopathy, glaucoma or those with congenital vision impairment, or according to previous involvement in rehabilitation services. Discussions were recorded and transcribed. Because many people were retired, leisure activities and personal independence were paramount. RESULTS/CONCLUSIONS: Younger people were concerned with gaining or continuing in employment or with educational opportunities. The age at onset of vision loss and the cause and duration of vision loss influence its impact. There appears to be a greater level of handicap in people with comorbid eye disease and related disease, such as diabetes.

Activities of Daily Living↗
PubMed1998

Reproducibility of automatic standard digital analysis of lens opacities.

PURPOSE: This study was designed to assess the repeatability of the standard analysis of images taken with the Nidek EAS-1000 anterior segment analysis system (Nidek Co. Ltd, Japan). METHODS: Participants in a large clinical trial (the vitamin E, cataract and age-related maculopathy study) were asked to undergo two independent examinations to assess the repeatability of primary outcome measures. After pupil dilatation to at least 6.5 mm, 104 eyes were photographed using the retro-illumination method and the slit-beam method. RESULTS: Intra-class correlation coefficients were: slit images, R = 0.982; retro-illumination images, R = 0.978. CONCLUSION: Repeatability of measurement of lens opacity from EAS-1000 images using automated standard analysis was high.

Aged↗
PubMed1998

Screening for diabetic retinopathy using a non-mydriatic retinal camera in rural Victoria.

PURPOSE: To develop a screening programme for the early detection of diabetic retinopathy using non-mydriatic retinal photography. METHODS: A community based screening service was offered to all people with known diabetes mellitus in selected townships in the LaTrobe and Goulburn Valleys in Victoria. At the local examination centre, basic sociodemographic information was collected as well as details of previous use of eye care services for the early detection of diabetic retinopathy. The examination included visual acuity (VA), glycosylated haemoglobin level and Polaroid photographs of each fundus using a Canon CR5-45NM non-mydriatic retinal camera (Canon, Tochigiken, Japan). Dilating drops were not used. Photographs were subsequently reviewed and letters were sent to all participants (with copies to their general practitioners) with recommendations for appropriate follow up. RESULTS: A total of 1177 people with diabetes attended the screening service, which is estimated to be 40% of the total population with known diabetes in the study area. The mean age was 65 years (range 20-94 years); 559 (48%) people reported not having a dilated fundus examination within the past 2 years; 345 (29%) people had never had a dilated fundus examination. Of the 2354 eyes, 2126 (90%) of the photographs were gradable. A total of 704 people (60%) had normal VA and no evidence of diabetic retinopathy, 209 people (18%) had diabetic retinopathy, 101 people (9%) had evidence of other fundus pathology, 42 people (3%) had reduced acuity (< 6/18) in one or both eyes (with no fundus pathology evident) and 121 people (10%) had ungradable photographs in one or both eyes. CONCLUSIONS: The present study demonstrates the usefulness of a screening programme with non-mydriatic retinal photography as an adjunct to current eye care services for the early detection of diabetic retinopathy.

Adult↗
PubMed1998

Use of focus groups to identify health promotion strategies for the early detection of diabetic retinopathy.

BACKGROUND: People with diabetes do not regularly utilise eye services for the early prevention of vision loss due to diabetic eye disease. A community-based screening program has been initiated in Victoria to address this issue. To encourage people to take preventive eye health care measures, the most effective health promotion strategies were identified. METHODS: Thirty-three health professionals were invited to attend focus groups. A sample of 35 people with diabetes was approached by their GPs or diabetes educators because of their motivation to participate in diabetes activities. Each group consisted of 10 members. Discussion points included the type of education messages available to people with diabetes; use of eye services among the participants with diabetes; and strategies required promoting the screening service. RESULTS: Five focus groups were conducted. The discussions highlighted that a great deal could be achieved by using local community networks to promote the benefits of early detection of diabetic retinopathy and local screening program. The group members recommended that particular attention be directed to general practitioners and their distribution of materials to patients. Key issues for planning and implementing the program were highlighted. The groups urged development of strategies to encourage people with diabetes in rural Victoria to participate in a program for the early detection of diabetic retinopathy.

Diabetic Retinopathy↗
PubMed1998

Use of eye care services by people with diabetes: the Melbourne Visual Impairment Project.

AIM: The use of eye care services by people with and without diabetes was investigated in the Melbourne Visual Impairment Project (VIP), a population based study of eye disease in a representative sample of Melbourne residents 40 years of age and older. METHODS: A comprehensive interview was employed to elicit information on history of diabetes, medication use, most recent visit to an ophthalmologist and optometrist, and basic demographic details. Presence and extent of diabetic retinopathy was determined by dilated fundus examination. RESULTS: The Melbourne VIP comprised 3271 people who ranged in age from 40 to 98 years; 46.2% of them were male. Of 3189 people who had the fundus examination and knew their diabetes status, 162 (5.1%) reported having been previously diagnosed with diabetes and, of these, 37 (22.2%) were found to have diabetic retinopathy. Seven people (4.3%) had developed diabetes before age 30. The mean duration of diabetes was 9.2 years. People with diabetes were significantly more likely to have visited an ophthalmologist ever or in the past 2 years than people without diabetes. However, 31.8% of people with diabetes had never visited an ophthalmologist. The proportion of people who had never seen an ophthalmologist was 47.1% for people without diabetes, 34.2% for people with diabetes but without diabetic retinopathy, and 25% for people with diabetic retinopathy. Sixty one per cent of people with diabetic retinopathy had seen an ophthalmologist in the past year and a further 3% within the past 2 years. People with diabetes were not significantly more likely to have visited an optometrist than people without diabetes (p = 0.51). Overall, 37.7% of people with diabetes and 32.9% of people without diabetes had visited an optometrist within the past year (chi 2 = 2.25, 1 df, p = 0.13). Information concerning retinal examinations was available for 135 individuals (83.3% of people with diabetes). Only 74 (54.8%) could recall ever having a dilated fundus examination; 10 (14%) by an optometrist, 62 (86%) by an ophthalmologist, and five (7%) by a general practitioner. Of those 68 people who had seen an ophthalmologist in the past 2 years, 48 (71%) reported a dilated fundus examination during that time. This compares with 28 (43%) reported dilated fundus examinations in the 65 people who had seen an optometrist in the past 2 years. This finding is statistically significant (chi 2 = 10.2, 1 df, p < 0.005). CONCLUSION: These results indicate that nearly half of people with diabetes in Melbourne are not receiving adequate screening or follow up for diabetic retinopathy, despite universal health care.

Adult↗
PubMed1998

Knowledge, attitudes, and self care practices associated with age related eye disease in Australia.

AIM: To determine the level of correct knowledge about common eye disease and attitudes towards blindness prevention and treatment, and how these factors influence self care practices in a population based sample. METHODS: A cluster random sample of the Victorian population was interviewed. The study population comprised residents aged 40 years of age or older living in five randomly selected Melbourne metropolitan suburbs and four randomly selected rural areas of Victoria. Questions were asked to ascertain each person's knowledge of common age related eye disease--that is, cataract, age related macular degeneration (AMD), and glaucoma. A subsample of the population was also asked questions to determine their attitudes to blindness prevention and treatment. All respondents were asked the year of their last visit to an eye practitioner. RESULTS: A total of 3184 (89%) eligible residents were assessed. Sex (females), age (younger people), higher levels of education (secondary, trade, or tertiary education), recent visit to an eye practitioner (within the past 2 years) and English spoken at home appeared to be significant predictors of knowledge of common age related eye conditions. Younger people believed blindness prevention and blindness treatment were the highest priorities compared with other diseases; people who spoke English at home and people with knowledge of common age related eye disease also considered blindness treatment to be the highest priority compared with other diseases. People with a previous diagnosis of age related eye disease, older people, females, people with correct knowledge of common eye diseases, and those who spoke English at home were significantly more likely to be under eye care. No interaction was found between knowledge and positive attitudes to self care practices. CONCLUSION: These data show that there is a large gap in the public's knowledge and understanding of eye disease that will need to be understood for eye health promotion activities.

Adult↗