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Susan Vitale

Publications and source records attributed to Susan Vitale.

15 recordsLinked to original sources
PubMed2006

Costs of refractive correction of distance vision impairment in the United States, 1999-2002.

OBJECTIVE: Correctable vision impairment caused by refractive error is common in the United States population. We estimated the direct costs of providing eyeglasses to all Americans (age> or =12) who need refractive correction to achieve good distance vision. DESIGN: Cross-sectional study of a nationally representative sample of United States citizens. PARTICIPANTS: Participants in the 1999-2002 National Health and Nutrition Examination Survey (NHANES), age > or = 12 years. The NHANES examines a nationally representative sample of the U.S. noninstitutionalized, civilian population. METHODS: Presenting and corrected visual acuity data were obtained using an autorefractor from 13,211 (93.0%) of the 14,203 participants who visited the NHANES Mobile Examination Center in 1999 through 2002. Need for refractive correction was defined by current use of corrective lenses for distance vision, improvement to good visual acuity following autorefractor correction (using several cutpoints to define good visual acuity), or both. MAIN OUTCOME MEASURES: Estimates of direct cost for refractive correction (1 pair of complete eyeglasses and a refraction examination) were computed based on Centers for Medicare & Medicaid Services fee schedules for 2000 and also based on expenditure data from the Medical Expenditure Panel Survey. RESULTS: The NHANES results indicate that >110 million Americans could or do achieve normal vision with refractive correction. The annual direct cost of correcting distance vision impairment is at least $3.8 billion. Of this amount, $780 million represents the annual cost of providing distance vision correction for persons > age 65. CONCLUSIONS: Correctable vision impairment due to refractive error is common in the United States population. These cost estimates provide useful information for public health endeavors aimed at provision of refractive correction to those who need it.

Adolescent↗
PubMed2006

Prevalence of visual impairment in the United States.

CONTEXT: The prevalence of visual impairment in the US public has not been surveyed nationally in several decades. OBJECTIVE: To estimate the number of US individuals aged 12 years or older who have impaired distance vision due to uncorrected refractive error. DESIGN, SETTING, AND PARTICIPANTS: The National Health and Nutrition Examination Survey (NHANES), using a multistage probability sampling design, included a vision evaluation in a mobile examination center. Visual acuity data were obtained from 13,265 of 14,203 participants (93.4%) who visited the mobile examination center in 1999-2002. Visual impairment was defined as presenting distance visual acuity of 20/50 or worse in the better-seeing eye. Visual impairment due to uncorrected refractive error was defined as (presenting) visual impairment that improved, aided by automated refraction results, to 20/40 or better in the better-seeing eye. MAIN OUTCOME MEASURES: Presenting distance visual acuity (measured with usual corrective lenses, if any) and distance visual acuity after automated refraction. RESULTS: Overall, 1190 study participants had visual impairment (weighted prevalence, 6.4%; 95% confidence interval [CI], 6.0%-6.8%), and of these, 83.3% could achieve good visual acuity with correction (95% CI, 80.9%-85.8%). Extrapolating these findings to the general US population, approximately 14 million individuals aged 12 years or older have visual impairment (defined as distance visual acuity of 20/50 or worse), and of these, more than 11 million individuals could have their vision improved to 20/40 or better with refractive correction. CONCLUSIONS: Visual impairment due to uncorrected refractive error is a common condition in the United States. Providing appropriate refractive correction to those individuals whose vision can be improved is an important public health endeavor with implications for safety and quality of life.

Adolescent↗
PubMed2006

Test-retest variability in structural and functional parameters of glaucoma damage in the glaucoma imaging longitudinal study.

PURPOSE: To determine the test-retest variability in perimetric, optic disc, and macular thickness parameters in a cohort of treated patients with established glaucoma. PATIENTS AND METHODS: In this cohort study, the authors analyzed the imaging studies and visual field tests at the baseline and 6-month visits of 162 eyes of 162 participant in the Glaucoma Imaging Longitudinal Study (GILS). They assessed the difference, expressed as the standard error of measurement, of Humphrey field analyzer II (HFA) Swedish Interactive Threshold Algorithm fast, Heidelberg retinal tomograph (HRT) II, and retinal thickness analyzer (RTA) parameters between the two visits and assumed that this difference was due to measurement variability, not pathologic change. A statistically significant change was defined as twice the standard error of measurement. RESULTS: In this cohort of treated glaucoma patients, it was found that statistically significant changes were 3.2 dB for mean deviation (MD), 2.2 for pattern standard deviation (PSD), 0.12 for cup shape measure, 0.26 mm for rim area, and 32.8 microm and 31.8 microm for superior and inferior macular thickness, respectively. On the basis of these values, it was estimated that the number of potential progression events detectable in this cohort by the parameters of MD, PSD, cup shape measure, rim area, superior macular thickness, and inferior macular thickness was 7.5, 6.0, 2.3, 5.7, 3.1, and 3.4, respectively. CONCLUSIONS: The variability of the measurements of MD, PSD, and rim area, relative to the range of possible values, is less than the variability of cup shape measure or macular thickness measurements. Therefore, the former measurements may be more useful global measurements for assessing progressive glaucoma damage.

Adult↗
PubMed2004

Comparison of the NEI-VFQ and OSDI questionnaires in patients with Sjögren's syndrome-related dry eye.

BACKGROUND: To examine the associations between vision-targeted health-related quality of life (VT-HRQ) and ocular surface parameters in patients with Sjögren's syndrome, a systemic autoimmune disease characterized by dry eye and dry mouth. METHODS: Forty-two patients fulfilling European / American diagnostic criteria for Sjögren's syndrome underwent Schirmer testing without anesthesia, ocular surface vital dye staining; and measurement of tear film breakup time (TBUT). Subjects were administered the Ocular Surface Disease Index (OSDI) and the 25-item National Eye Institute Vision Functioning Questionnaire (NEI-VFQ). Main outcome measures included ocular surface parameters, OSDI subscales describing ocular discomfort (OSDI-symptoms), vision-related function (OSDI-function), and environmental triggers, and NEI-VFQ subscales. RESULTS: Participants (aged 31-81 y; 95% female) all had moderate to severe dry eye. Associations of OSDI subscales with the ocular parameters were modest (Spearman r (rho) < 0.22) and not statistically significant. Associations of NEI-VFQ subscales with the ocular parameters reached borderline significance for the near vision subscale with TBUT (rho = 0.32, p =.05) and for the distance vision subscale with van Bijsterveld score (rho = 0.33, p =.04). The strongest associations of the two questionnaires were for: ocular pain and mental function with OSDI-symptoms (rho = 0.60 and 0.45, respectively); and general vision, ocular pain, mental function, role function, and driving with OSDI-function (rho = 0.60, 0.50, 0.61, 0.64, 0.57, and 0.67, respectively). CONCLUSIONS: Associations between conventional objective measures of dry eye and VT-HRQ were modest. The generic NEI-VFQ was similar to the disease-specific OSDI in its ability to measure the impact of Sjögren's syndrome-related dry eye on VT-HRQ.

Adult↗
PubMed2004

Dry eye signs and symptoms in women with premature ovarian failure.

OBJECTIVE: To examine whether women with premature ovarian failure (POF) have abnormal findings in ocular surface or tear parameters and whether they report symptoms of ocular discomfort compared with age-matched controls. METHODS: Sixty-five patients with POF and 36 age-matched healthy controls were examined for signs and symptoms of dry eye. The Ocular Surface Disease Index questionnaire and the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ 25) were administered to the participants. Assessments of ocular surface damage (Oxford and van Bijsterveld scores of vital dye staining) and tear status (Schirmer tests 1 [without anesthesia] and 2 [with anesthesia] and tear breakup time) were performed. RESULTS: Women with POF scored significantly worse than controls on all ocular surface damage parameters: Oxford score (3.2 vs 1.7; P =.001), conjunctival lissamine green (2.1 vs 1.3; P =.02), corneal fluorescein staining (1.2 vs 0.4; P =.005), and van Bijsterveld score (2.1 vs 1.3; P =.02). Further, the proportion of patients with POF meeting the dry eye diagnostic criterion of a van Bijsterveld score greater than or equal to 4 was significantly greater among women with POF than among controls (20% vs 3%; P =.02). The POF group also tended to have worse scores than controls on self-reported symptoms, as measured by the overall Ocular Surface Disease Index (12.5 vs 2.1; P<.001) and the overall NEI-VFQ (94 vs 98; P =.001) after adjustment for age and race. Schirmer test scores and tear breakup time did not differ. CONCLUSIONS: Women with POF were more likely to exhibit ocular surface damage and symptoms of dry eye than age-matched controls. They were not, however, more likely to have reduced tear production. To our knowledge, this association between ocular surface disease and POF has not been previously reported. These data provide further evidence of the multifaceted role of sex hormones in the health and disease of the ocular surface.

Adolescent↗
PubMed2004

A randomized, placebo-controlled, crossover clinical trial of super blue-green algae in patients with essential blepharospasm or Meige syndrome.

PURPOSE: To evaluate the effectiveness of super blue-green algae (SBGA) supplements on the severity of essential blepharospasm treated with botulinum toxin A injections. DESIGN: Double-masked, placebo-controlled, two-period, crossover randomized trial. PATIENTS AND METHODS: The study was carried out in patients with essential blepharospasm or Meige syndrome undergoing routine treatment with botulinum toxin A injections. INTERVENTION: Patients were randomly assigned to either SBGA capsules or placebo. After 6 months of treatment, patients underwent a 6-month washout period with no treatment, then were administered the alternate treatment for an additional 6 months, thus serving as their own controls. MAIN OUTCOME MEASURES: Video documentation of blink rate and involuntary facial movements, time between botulinum toxin A injections, and patients' subjective assessment of the impact of blepharospasm on functioning were obtained at the beginning and end of the first and second (crossover) treatment periods. RESULTS: A total of 24 patients (10 men, 14 women; aged 42 to 83 years) completed both treatment periods. Mean within-patient difference in blink rate between SBGA and placebo periods was -2.1 blinks per 2 minutes (95% confidence interval [CI]: -20.8-+31.9), not statistically different from zero (P =.83). Mean within-patient difference in time between injections between SBGA and placebo periods was 4.6 days (95% CI: -13.3-+22.5), not statistically different from zero (P =.62). The lack of statistical significance may have been because of small sample size. There were no significant differences in severity of involuntary movement between SBGA and placebo treatment periods. However, patients were more likely to report limitation in function during the period they took SBGA than during the period they took placebo (odds ratio, 0.2; P =.03). CONCLUSION: Overall, we found no evidence of a beneficial effect of SBGA as an adjunct to botulinum toxin A injections; however, a few patients, all younger than 60 years, did appear to benefit from SBGA.

Adult↗
PubMed2004

Astigmatism outcomes of horizontal temporal versus nasal clear corneal incision cataract surgery.

PURPOSE: To compare the short- and long-term astigmatism outcomes after cataract surgery using temporal clear horizontal corneal incisions and nasal horizontal clear corneal incisions. SETTING: Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, Maryland, USA. METHODS: This retrospective study included a consecutive series of eyes having phacoemulsification with implantation of a 6.0 mm foldable acrylic intraocular lens through a 3.5 mm horizontal clear corneal incision at 180 degrees (temporal incision in right eyes, nasal incision in left eyes). Astigmatism was measured by keratometry readings before surgery and 6 weeks and 12 months postoperatively. RESULTS: The mean preoperative astigmatism in the 178 eyes (94 right, 84 left) of 161 patients was 0.78 diopter (D); 54.5% of eyes had against-the-rule (ATR) astigmatism, 22.5% had with-the-rule (WTR) astigmatism, and 14.0% were astigmatically neutral. A significant shift toward WTR astigmatism occurred postoperatively. At 6 weeks, 48.3% of eyes had WTR astigmatism and 23.0% had ATR astigmatism. At 12 months, 43.8% had WTR astigmatism and 25.8% had ATR astigmatism. Vector analysis revealed a mean surgically induced astigmatism (SIA) of 1.17 D at 6 weeks and 1.04 D at 12 months. The side of the incision significantly affected SIA. At 6 weeks, temporal incisions yielded a mean SIA of 0.74 D and the nasal incisions, of 1.65 D. This trend in SIA persisted at 12 months: 0.71 D for temporal incisions and 1.41 D for nasal incisions. CONCLUSIONS: Cataract surgery using a horizontal clear corneal incision induced WTR astigmatism 6 weeks and 12 months postoperatively. Temporal incisions induced significantly less astigmatism than nasal incisions.

Aged↗
PubMed2004

Supplemental oxygen improves diabetic macular edema: a pilot study.

PURPOSE: Diabetic macular edema (DME) is the most common cause of moderate visual disability in persons of working age in the United States. The pathogenesis of DME is poorly understood. In this study, the effect of retinal hypoxia in the development and maintenance of DME was investigated. METHODS: Five patients with chronic DME despite at least one focal laser photocoagulation treatment (nine eyes) received 4 L/min of inspired oxygen by nasal cannula for 3 months. Best corrected visual acuity (VA) and retinal thickness, assessed by optical coherence tomography (OCT), were measured at baseline, during 3 months of oxygen treatment, and for 3 months after stopping oxygen. RESULTS: After 3 months of oxygen therapy, nine of nine eyes with DME at baseline showed a reduction in thickness of the center of the macula. Foveal thickness (FTH) above the normal range was reduced by an average of 43.5% (range, 14%-100%), excess foveolar thickness (CEN) was reduced by an average of 42.1% (range, 13%-100%), and excess macular volume was reduced by an average of 54% (range, 35%-100%). Statistical analyses suggested that these changes were unlikely to be due to chance (P = 0.0077 by Wilcoxon signed-rank test). Three eyes showed improvement in VA by at least 2 lines, one by slightly less than 2 lines, and five eyes showed no change. Three months after discontinuation of oxygen, five of the nine eyes showed increased thickening of the macula compared with when oxygen was discontinued. CONCLUSIONS: Supplemental inspired oxygen may decrease macular thickness due to DME, suggesting that retinal hypoxia is involved in the development and maintenance of DME.

Aged↗
PubMed2002

Comparison between retinal thickness analyzer and optical coherence tomography for assessment of foveal thickness in eyes with macular disease.

PURPOSE: To use the retinal thickness analyzer (RTA) and optical coherence tomography (OCT) scanners for quantitative measurement of retinal thickness in eyes with macular disease. DESIGN: In a cross-sectional study, 44 patients (55 eyes) with macular disease and sufficient media clarity to visualize the fundus using clinical biomicroscopy underwent an ophthalmologic examination, fluorescein angiography, RTA, and OCT during the same visit. METHODS: Foveal and foveal center (foveolar) retinal thickness measurements were obtained by RTA and by OCT. RESULTS: Retinal thickness measurements were obtained by OCT in all 55 eyes and by RTA in 34 eyes (62%, primarily due to interference from media opacities). In the 34 eyes in which measurements were obtained by both instruments, mean foveal thickness was 291 and 269 microm for OCT and RTA, respectively; foveolar thickness was 277 and 265 microm, respectively. OCT and RTA measurements of foveal thickness were strongly correlated (intraclass correlation coefficient = 0.89), as were measurements of the foveolar thickness (intraclass correlation coefficient = 0.94). Topographic maps generated by the two techniques yielded qualitatively similar information. CONCLUSIONS: Overall, there was excellent agreement between RTA and OCT measurements. Each technique has advantages that may make its use preferable in a particular subgroup of eyes or to describe a particular disease process. An important consideration is that media opacities create less interference for OCT than for RTA, so that in study populations with a moderate-to-high prevalence of media opacity, images can be obtained in a greater percentage of eyes by OCT than by RTA.

Aged↗
PubMed2002

A fundus camera dedicated to the screening of diabetic retinopathy in the primary-care physician's office.

PURPOSE: To increase the number of diabetic patients being screened for retinopathy, an instrument, the DigiScope, was specifically designed to operate in primary-care physicians' offices. The DigiScope is described and its automated functions are evaluated. METHODS: The DigiScope consists of a semiautomated optical head to acquire fundus images, evaluate visual acuity, and transmit the data to a remote reading center through telephone lines. Normal volunteers and 17 consecutive diabetic patients visiting their primary-care physician were recruited, and nonophthalmic staff performed the acquisition session. RESULTS: The pupil center and working distance were set automatically. Centering was achieved within 750 microm in less than 500 ms. The fundus was successfully focused by an automated algorithm, and an imaging session covering 71 degrees of the posterior pole of both eyes lasted 5.6 +/- 2.4 minutes. It was found that a file-compression ratio of 12 did not degrade the clinical information and allowed data transfer in less than 6 minutes. A pilot study in normal eyes showed that the DigiScope images yielded the same amount of details as conventional color fundus photographs obtained by an expert photographer. CONCLUSIONS: The DigiScope fulfills the instrumental requirements for a practical and cost-effective tool to acquire data needed to identify diabetic patients who must be referred to an eye-care specialist. Widespread screening with the DigiScope may help reduce the risk of vision loss in an estimated 4 million individuals in the United States alone, who currently do not undergo an annual eye examination.

Diabetic Retinopathy↗
PubMedDate not supplied

Relation between retinal thickening and clinically visible fundus pathologies in mild nonproliferative diabetic retinopathy.

BACKGROUND AND OBJECTIVE: To determine the association of retinal thickening (RT) with clinically observable retinal pathologies in eyes with mild nonproliferative diabetic retinopathy. PATIENTS AND METHODS: Using an objective quantitative imaging method (Retinal Thickness Analyzer), the ratio relative to normal RT (RTI) was measured in 23 eyes with and 35 eyes without clinically observable diabetic fundus pathology. RTI was analyzed in relation to presence of mild diabetic retinal lesions in the +/-0.5 mm vicinity. RESULTS: The percent of eyes with RTI significantly above normal values did not differ significantly between eyes with and without retinopathy (30% vs 34%). Mean RTI was not associated with local presence of microaneurysms (P=0.92), soft exudates (P=0.55), or retinal hemorrhages (P=0.31). Areas without hard exudates had significantly greater mean RTI (1.10) than areas with exudates (0.97, P=0.009). CONCLUSION: In diabetic patients with mild retinopathy, areas with and without clinically observable retinal pathologies had similar retinal thickness. We conclude that clinical strategies for detection of retinal thickening should not be limited to areas with visible fundus pathologies.

Adult↗
PubMedDate not supplied

A comparison of quantitative mapping and stereoscopic fundus photography grading of retinal thickness in diabetic eyes with macular edema.

OBJECTIVE: To evaluate the ability of a retina specialist's grading of 30 degrees color stereoscopic fundus photographs to identify areas of significant retinal thickening as assessed by the Retinal Thickness Analyzer (RTA) and to determine whether this ability was affected by the presence of retinal pathology. MATERIALS AND METHODS: Thirty-two eyes in 29 patients clinically diagnosed as having diabetic macular edema underwent RTA scanning and nonsimultaneous 30 degrees color stereoscopic fundus photography. Retinal thickness maps of the macular area were generated, and regions with significant retinal thickening (> or = 2 SD above normal values) were identified. A retina specialist reader, masked to the RTA measurements, identified areas with macular edema on the stereoscopic fundus photographs, which subsequently were overlaid on the retinal thickness maps. The sensitivity (percent of significant retinal thickening areas identified by the retina specialist grading the stereoscopic fundus photographs) was calculated separately for areas with and without retinal pathology. Specificity of the stereoscopic fundus photograph grading was assessed similarly. RESULTS: The retina specialist's stereoscopic fundus photography grading identified 78.8% of areas with significant retinal thickening (range over eyes: 20.4%-100%) and was slightly more likely to identify significant retinal thickening when pathology was present (89.6%) than when pathology was not present (78.4%; pooled risk ratio, 1.14 [95% CI = 0.54, 2.42]). Specificity of stereoscopic fundus photography grading was 58%, ie, 42% of areas without significant retinal thickening were (incorrectly) identified as edematous by the stereoscopic fundus photograph grading. This misidentification was more likely if pathology was present (76.9%) than if pathology was not present (41.1%; pooled risk ratio, 1.87 [95% CI = 1.28, 2.73]). CONCLUSION: This study shows the determination of macular edema by a retina specialist reading color stereoscopic fundus photographs is sensitive but not specific with reference to edema identified by the RTA. Furthermore, the presence of retinopathy tends to cause false-positive readings with reference to edema identified by the RTA. These findings indicate the need to use objective, quantitative methods in clinical studies to detect and monitor macular edema.

Diabetic Retinopathy↗