Jacques Gresset

Functional outcome and satisfaction after photorefractive keratectomy: Part 2: survey of 690 patients

PURPOSE To document patient satisfaction and self-perceived quality of vision after bilateral photorefractive keratectomy (PRK). DESIGN Noncomparative, interventional case series. PARTICIPANTS Consecutive patients who underwent bilateral PRK from May 1994 through May 1997 by the 12 surgeons of four collaborating centers with a minimum of 4 months since the last surgery and up to 30 months since the first surgery. METHODS A questionnaire with known psychometric properties was self-administered by the patients. MAIN OUTCOME MEASURES Responses to individual questions and scale scores. RESULTS A total of 929 questionnaires were sent, of which 690 were answered and returned (74.3% response rate). The preoperative spherical equivalent ranged from -0.38 diopters [D] to -27.75 D (mean, -5.32 D; standard deviation, 2.85 D). Although 91.8% of the patients were satisfied or very satisfied with their surgery, 96.3% considered that their main goal had been reached, and 95.7% would still choose to have surgery if they had it to do over. The degree of satisfaction was proportional to the postoperative uncorrected visual acuity in the best eye expressed in LogMAR (r = -0.18, P: = 0. 0001) and was negatively correlated with the importance of the corneal haze (r = -0.23, P = 0.0001). Daytime glare was reported to be greater than before surgery by 55.1% of patients. A decrease in night vision was reported by 31.7% of patients, and 31.1% of patients reported increased difficulty driving at night because of their vision. CONCLUSIONS Overall satisfaction after PRK for low to severe myopia appears to be very good. Glare and night vision disturbance, particularly bothersome for night driving, seem to constitute significant secondary effects that deserve further investigation and should be kept in mind for future improvements in the technique.

Effectiveness and safety of screening for diabetic retinopathy with two nonmydriatic digital images compared with the seven standard stereoscopic photographic fields.

BACKGROUND The use of nonmydriatic cameras, which offer ease of screening and 45 degrees immediate imaging of the fundus, is gaining increasing acceptance for screening programs tailored to diverse conditions. We performed a study to evaluate the effectiveness and safety of screening for diabetic retinopathy with two nonmydriatic camera images compared with the seven standard stereoscopic 30 degrees fields (7SF). We also wished to determine whether safe screening guidelines could be established to identify patients needing referral to an ophthalmologist. METHODS In this prospective masked cross-sectional study, we evaluated agreement in the assessment of the severity of diabetic retinopathy by means of two 45 degrees images centred on the optic disc and on the macula obtained with the Topcon CRW6 nonmydriatic camera and by means of 7SF photography and ophthalmologic slit-lamp biomicroscopy, both performed with pupil dilation. Between November 2000 and June 2001, 98 adult patients known to have type 1 or 2 diabetes mellitus who presented for the first time to the diabetic retinopathy clinic of a tertiary care centre in Montreal were enrolled consecutively. Thus, patient recruitment was weighted toward more severe retinopathy to ensure sufficient representation of less frequent but more severe levels. Each patient underwent nonmydriatic fundus photography of both eyes, followed by a complete ophthalmologic examination with pupil dilation by a single retina specialist and 7SF photography of both eyes with pupil dilation. The level of retinopathy was graded independently in each eye from the 7SF photographs according to the Early Treatment Diabetic Retinopathy Study (ETDRS) scale by two graders; an independent retina specialist adjudicated the rare instances of interreader disagreement in a masked fashion. Two months later, two graders independently graded the nonmydriatic images in a blinded fashion according to the ETDRS scale; a third observer adjudicated the rare instances of interreader disagreement. We measured concordance between grading results with the various screening techniques using the weighted and unweighted kappa statistic. We used sensitivity and specificity indices to determine safe screening guidelines to identify patients needing referral to an ophthalmologist. RESULTS There was substantial agreement in the grading of retinopathy with nonmydriatic camera imaging and with 7SF photography, both for all eyes (kappa = 0.626 [standard deviation (SD) 0.045]) and for the eye with more severe disease (kappa = 0.654 [SD 0.063]). With nonmydriatic camera imaging, screening thresholds for patient referral to an ophthalmologist of very mild retinopathy (ETDRS grade 20), mild retinopathy (ETDRS grade 35) and moderate retinopathy (EDTRS grade 43) had sensitivity values of 97.9%, 97.1% and 53.3% respectively and specificity values of 81.3%, 95.5% and 96.9% respectively. Screening thresholds of very mild or mild retinopathy both correctly identified 100% of eyes with severe nonproliferative or proliferative retinopathy. With a screening threshold of mild retinopathy, screening with the nonmydriatic camera would lead to referral to an ophthalmologist of 37.8% of patients because of detected disease and of an additional 17.3% because of insufficient image quality in at least one eye, for a total of 55.1%. The overall sensitivity and specificity of a two-field nonmydriatic screening strategy with a threshold of mild retinopathy for referral of patients with insufficient image quality in at least one eye are 97.7% and 84.0% respectively. INTERPRETATION Our results suggest that two-field nonmydriatic camera imaging is a safe screening strategy that may identify the patients with diabetes most in need of ophthalmologic care.

Participation in daily activities and social roles of older adults with visual impairment

Purpose. (1) to document participation in daily activities and social roles of older adults seeking services for visual impairment (VI) and compare it with that of the older population without VI or other disabilities, and (2) to explore correlates of their participation. Methods. The 64 participants (46 women) had an average age of 79.3 years (SD = 5.9 years) and presented various types of VI. Participants were interviewed at home to collect information regarding their visual function (National Eye Institute Visual Function Questionnaire-25), sociodemographic and clinical characteristics, including depressive symptoms (Geriatric Depression Scale), and participation (Assessment of Life Habits/LIFE-H). Each participant was matched with another person without disabilities randomly recruited from the community. Results for the two populations on the Life-H participation domains were compared using t-tests. In the group with VI, general information (independent variables) was examined in relation to participation main scores (dependent variables), followed by multiple linear regression analyses. Results. Participation in daily activities and social roles of participants with VI (mean ± SD (/9) = 6.8 ± 1.0 and 5.6 ± 1.6, respectively) was significantly lower than that of participants without VI (8.1 ± 0.4 and 8.3 ± 0.4) (p < 0.0001). Depressive symptoms and perceived quality of distance vision were the strongest correlates and together explained more than 65% of the variance in the participation scores of the subjects with VI. Conclusions. This study demonstrates the participation restrictions associated with VI and underlines the importance of psychological aspects in participation.

Functional outcome and satisfaction after photorefractive keratectomy. Part 1: development and validation of a survey questionnaire.

OBJECTIVE The aim of this study was to develop a valid, reliable, and easy-to-administer instrument to assess patient satisfaction and perceived outcome after bilateral excimer laser photorefractive keratectomy. DESIGN Development and validation of a psychometric questionnaire. PARTICIPANTS Consecutive patients who underwent bilateral excimer laser photorefractive keratectomy from May 1994 through May 1997 by 12 surgeons from four collaborating centers. To be eligible, a minimum of 4 months since the last surgery and a maximum of 30 months since the first surgery was required. METHODS The new instrument was derived in part from the Prospective Evaluation of Radial Keratotomy (PERK) study 10-year psychometric questionnaire and the Visual Functional Index (VF-14), an index of functional impairment in patients with cataract. Questions were grouped in seven scales, each covering a specific aspect of quality of vision. These included global satisfaction, quality of uncorrected vision, quality of corrected vision, quality of night vision, glare, daytime driving, and night driving. MAIN OUTCOME MEASURES Acceptability, reliability, validity, and interpretability of the instrument, as well as its ease of administration. RESULTS The instrument scale structure was examined and scale scores were created. Item-discriminant validity ensured that questions belonged to their hypothesized scale, based on multitrait correlation analysis. The instrument was shown to be reliable by a high level of internal consistency, and all Cronbachs alpha coefficients were superior or equal to 0.83. Construct-related validity and interpretability were assessed based on correlations between scale scores and clinically recognized success criteria such as visual acuity and refraction. Respondent burden was shown to be minimal. Acceptability of the instrument was shown to be very good, with a participation rate of 74.3% (690 of 929 patients). The instrument is available in English and in French and the translation was shown to be reliable. CONCLUSIONS The acceptability, reliability, and interpretability of the instrument, as well as its ease of administration, were shown to be adequate. This questionnaire appears clinically useful to document patient satisfaction after excimer laser photorefractive keratectomy.

The VF-14 index of functional visual impairment in candidates for a corneal graft ☆

PURPOSE To validate the Visual Function-14 (VF-14) index of functional visual impairment in candidates for a corneal graft. METHODS One hundred thirty-four patients who were candidates for a corneal graft participated in this study between August 1996 and February 1997. Demographic, ocular history, best-corrected visual acuity, and detailed ocular examination data were collected. Functional visual impairment information was obtained by telephone interviews using the following: VF-14, SF-36 (Short Form-36, a more generic measure of general health function), and Visual Symptom Score, and four questions measuring the overall amount of trouble with vision, dissatisfaction with vision, ocular pain, and discomfort. RESULTS The average age of corneal graft candidates was 64 +/- 18 years (range, 18 to 90 years) and 60% were women. The most frequent corneal disease was pseudophakic bullous keratopathy (41%). Ocular comorbidities included glaucoma or ocular hypertension (30%) and cataract (19%). The mean best-corrected visual acuity of the eye scheduled for surgery was 1.33 +/- 0.56 logMAR whereas the best eye best-corrected visual acuity was 0.36 +/- 0.44 logMAR. The mean VF-14 score was 73% +/- 26%, and the internal consistency was high, with a Cronbach alpha value of 0.94. The VF-14 correlated strongly with the best eye best-corrected visual acuity. It also correlated strongly with the Visual Symptom Score, the global measures of trouble and dissatisfaction with vision. Candidates for a corneal graft had low scores for all eight general health concepts evaluated with the SF-36, and the VF-14 correlated with seven of the eight SF-36 subscales. CONCLUSION The VF-14 is a valid measure of functional visual impairment in candidates for a corneal graft. The Visual Symptom Score and the SF-36 are also useful indices in such patients.

Cataract-related vision loss and depression in a cohort of patients awaiting cataract surgery

OBJECTIVE As provinces consider what an acceptable cataract surgery wait time should be, research is needed on the risk of adverse events, such as depression, while waiting for care. We sought to determine whether worse visual acuity is related to depressive symptoms in patients waiting to have cataract surgery. DESIGN Cohort study. PARTICIPANTS Six hundred seventy-two patients awaiting cataract surgery were recruited from Maisonneuve-Rosemont Hospital in Montreal, Que. METHODS About 2 weeks before surgery and 4 months after surgery, patients completed the Visual Function-14 questionnaire, a measure of the self-report of difficulty performing visual tasks, and the 30-item Geriatric Depression Scale. Patients were also asked about systemic and ocular comorbidities. Visual acuity was measured with pinhole correction. Date of entry onto the hospital waiting list and date of cataract surgery were recorded. RESULTS Forty-one percent of patients had visual acuity of 6/18 or worse in the surgical eye, whereas 26% showed signs of depression before surgery (Geriatric Depression Scale-30 > or = 10). In a logistic regression model, those with visual acuity < or = 6/18 in their surgical eye had a 59% higher adjusted odds of depression (odds ratio 1.59, 95% CI 1.09-2.33). There was statistically significant evidence that the relationship between visual acuity and depression was mediated by greater reported difficulty on the Visual Function-14 (p < 0.05). CONCLUSIONS Patients with worse visual acuity were more likely to be depressed while waiting for cataract surgery. Shortening the wait time for cataract surgery, especially for those with worse vision, could potentially reduce the risk or shorten the duration of depression.

Comparison of two, three and four 45° image fields obtained with the Topcon CRW6 nonmydriatic camera for screening for diabetic retinopathy

BACKGROUND The use of the nonmydriatic camera is gaining increasing acceptance for the detection of diabetic retinopathy when integrated into a community-tailored program. We performed a study to evaluate the optimal number and positioning of photographic fields necessary to screen for diabetic retinopathy with the Topcon CRW6 nonmydriatic camera. METHODS In this prospective masked cross-sectional comparative study, we compared the assessment of diabetic retinopathy using two, three or four 45 degrees fundus images (centred respectively on the disc and the macula; on the disc, on the macula and temporal to the macula; and on the disc, on the macula, temporal to the macula and superotemporal to the macula, including the superior temporal vein) acquired with the Topcon CRW6 nonmydriatic camera, with the grading of the seven standard stereoscopic 30 degrees field photographs (7SF). The study population consisted of 98 consecutive adult patients known to have type 1 or 2 diabetes mellitus who presented for the first time to the diabetic retinopathy clinic of a tertiary care centre in Montreal. All patients underwent four nonmydriatic fundus photography sessions of both eyes, 7SF photography with pupil dilation and a complete ophthalmologic examination with pupil dilation by a retina specialist. RESULTS Compared to the 7SF, the sensitivity and specificity of screening for any retinopathy (Early Treatment Diabetic Retinopathy Study [ETDRS] grade greater than 10) using the two central fields were 95.7% and 78.1% respectively. The corresponding values with three image fields were 97.6% and 71.9%, and with four image fields, 97.6% and 65.6%. The sensitivity and specificity of screening for mild or worse disease (ETDRS grade 35 or greater) using the two central fields were 87.5% and 92.3%. The corresponding values with three image fields were 88.9% and 94.6%, and with four image fields, 88.9% and 91.9%. Poor image quality occurring with the addition of extra fields resulted in an increase of 6.2% in the rate of referral to an ophthalmologist. The use of two image fields missed no cases of retinopathy. INTERPRETATION The use of image fields in addition to the two 45 degrees images centred on the disc and the macula on imaging with the Topcon CRW6 nonmydriatic camera did not significantly increase the sensitivity or specificity of screening for diabetic retinopathy. Contrary to the desired effect, the addition of fields resulted in diminished utility and cost-effectiveness of this screening approach.

The VF-14 index of visual function in recipients of a corneal graft: a 2-year follow-up study.

PURPOSE To assess visual functioning and other health-related quality of life outcomes after corneal grafting. DESIGN A cohort study of corneal graft recipients observed for a minimum of 2 years after transplantation. METHODS Repeated measurements were obtained by telephone interviews preoperatively and later at 1 and 2 years post-corneal transplantation in 217 patients with the following questionnaires: visual function index (VF-14), visual symptom score and global measures of trouble with vision, dissatisfaction with vision, ocular pain, and discomfort. Demographic, past ocular history, repeated best-corrected visual acuity (BCVA), and detailed eye examination data were also collected. RESULTS Grafted eyes gained a mean of more than four lines of vision on the Early Treatment Diabetic Retinopathy Study (ETDRS) chart 1 year after transplantation. The mean visual function index (VF-14) score improved from 68% +/- 26% preoperatively to 81% +/- 21% at 1 year. Average visual acuity (VA) and VF-14 values were unchanged at 2 years. The activities of daily living that showed the largest and most significant improvement were reading small print, driving in daytime, and watching television. A number of subjects (9%) presented with a maximum VF-14 score preoperatively, leaving no room for improvement with this outcome index. The VF-14 was especially responsive for corneal graft candidates with low levels of vision before surgery. Blurry vision, pain and discomfort scores, and the global measures of trouble and dissatisfaction with vision also improved after corneal grafting. CONCLUSION The VF-14 index of functional visual impairment is a responsive and useful outcome index in recipients of a corneal graft.

Health-related and subjective quality of life of older adults with visual impairment

Purpose. To document health-related quality of life (HRQOL) and subjective quality of life (SQOL) and explore their correlates in older adults seeking services for visual impairment (VI). Method. A convenience sample of 64 participants (79.3 ± 5.9 years) with VI was interviewed at home. HRQOL was measured with the Visual Function Questionnaire-25 and SQOL with the Quality of Life Index. The potential correlates were as follows: personal factors (sociodemographic characteristics, co-morbidity, depressive symptoms, activity level), environmental factors (technical aids, social support) and participation in daily activities and social roles (level and satisfaction). Results. Compared to normative data from previous studies of older adults, the participants had lower HRQOL but similar SQOL. Greater level of participation in social roles, higher perceived activity level, use of a writing aid and greater satisfaction with participation in social roles together explained better HRQOL (R2 = 0.66). Fewer depressive symptoms, greater satisfaction with participation in social roles and with social support and fewer co-morbidities together explained better SQOL (R2 = 0.70). Conclusions. HRQOL of older adults with VI is mainly explained by level of participation correlates, while their SQOL is mainly explained by depressive symptoms and satisfaction variables. The results also underscore the importance of social roles for HRQOL and SQOL of this population.

Prevalence of visual impairment and utilization of rehabilitation services in the visually impaired elderly population of Quebec

Data on the prevalence of reported visual impairment and on the utilization of rehabilitation services were collected on a sample consisting of 1777 community-residing people aged at least 65 years. A visual disability was considered to be present if the answer to at least one of the following two questions was positive: Do you have trouble reading ordinary newsprint with glasses (if normally worn)? Do you have trouble clearly seeing the face of someone 12 feet away with glasses (if normally worn)? Prevalence of a reported near disability was 7.6%, prevalence of a reported distance disability was 4.4%, and 3.5% of subjects reported both types of disability. In a subsample of the surveyed population, the positive predictive value was 21% and the negative predictive value was 100%, using moderate or worse visual impairment as the gold standard. Among those answering yes to both questions, 11.4% received services from a rehabilitation center and 10.0% from a nonprofit agency. The utilization rates (adjusted to apply only to those whose visual impairment was confirmed by visual examination) reached 20% for rehabilitation centers and 17.5% for nonprofit agencies. Low utilization of rehabilitation services raises questions concerning the role of general eye care practitioners, community-based health centers, and rehabilitation centers in the rehabilitative process of the visually impaired elderly.