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At least 73 records · Page 4Linked to original sources
PubMed2003

Comparison of contrast sensitivity, visual acuity, and Humphrey visual field testing in patients with glaucoma.

BACKGROUND: Despite their normal or near-normal Snellen visual acuity, patients with glaucoma often complain of "poor" vision. OBJECTIVE: To investigate the relationship between large-letter contrast sensitivity, high-contrast visual acuity, and visual field defects in patients with glaucoma who have 20/40 or better visual acuity. DESIGN: Prospective, cross-sectional case series. PATIENTS AND METHODS: We evaluated 250 eyes of 144 subjects from the Glaucoma Service at the University of Illinois at Chicago College of Medicine. Subjects with a diagnosis of glaucoma, suspected glaucoma, or ocular hypertension who met the 20/40 or better vision requirement were recruited. Visual acuity was measured using the rear-illuminated Lighthouse Visual Acuity Chart at 4 m. Contrast sensitivity was measured using the Pelli-Robson Chart in a front-illuminated box with even luminance across the chart. Visual fields of the patients were measured using the 24-2 full-threshold program on the Humphrey Visual Field Analyzer. RESULTS: A significant correlation (r = 0.57, P < 0.001, n = 127) was found between the visual field mean deviations and the contrast sensitivity scores. The correlation (r = -0.322, P < 0.001, n = 127) was less between the visual field mean deviation and the log MAR visual acuity values, as was the correlation between the contrast sensitivity scores and log MAR visual acuity values (r = -0.370, P < 0.001, n = 127). In the subgroup of patients with chronic open-angle glaucoma, the correlation between the mean visual field deviation and the contrast sensitivity score was higher at 0.689 (P < or = 0.001, n = 62). CONCLUSIONS: Reduced contrast sensitivity is significantly correlated with visual field losses in patients with glaucoma and a visual acuity of 20/40 or better. The study data support the conclusion that, compared with visual acuity, the disease process preferentially affects contrast sensitivity. In our previous work, contrast sensitivity was shown to be more related than visual acuity to real-world function in patients with early glaucomatous changes.

Contrast Sensitivity↗
PubMed2005

Poor prognosis of visual outcome after visual loss from giant cell arteritis.

OBJECTIVE: To evaluate the incidence and extent of visual recovery in patients with giant cell arteritis (GCA) treated with high doses of systemic corticosteroids. DESIGN: Multicenter prospective case series. PARTICIPANTS: Thirty-four consecutive patients with biopsy-proven GCA and visual loss seen at either Wills Eye Hospital in Philadelphia or Auckland Hospital in New Zealand from 2001 to 2004 were evaluated prospectively. METHODS: All patients underwent a complete neuro-ophthalmic evaluation that included Snellen visual acuity, pseudoisochromatic Ishihara color plates, visual fields, intraocular pressure, slit-lamp examination, and binocular ophthalmoscopy. Formal visual field testing was performed on all patients who were capable of completing the test. All patients were treated with a standard protocol of 1 g of IV methylprednisolone daily for 3 days followed by oral prednisone 60 or 80 mg (depending on patient weight). Patients were evaluated initially at 2-week intervals (14-19 days) and then monthly (4-5 weeks), with subsequent dosages of prednisone modified based on erythrocyte sedimentation rate, C-reactive protein, and patient symptoms. At each visit, patients underwent a repeat complete neuro-ophthalmic evaluation. MAIN OUTCOME MEASURES: Alterations in visual acuity, visual field, and color vision. RESULTS: Patients with visual loss from GCA had a mean visual acuity of 20/400. Visual deterioration occurred in 27% of eyes within the first week despite high-dose IV corticosteroids. Fifteen percent of eyes showed an improvement of visual acuity within the first month, but only 5% have corresponding improvement in visual field. CONCLUSIONS: Visual recovery is uncommon in patients who lose vision from GCA. Recovery in visual acuity is not associated with visual field or color vision improvement in this series. Visual deterioration occurs in approximately 27% of eyes despite high-dose IV methylprednisolone. The greatest risk of visual deterioration is in the first 6 days.

Administration, Oral↗
PubMed1995

Confrontation visual field loss as a function of decibel sensitivity loss on automated static perimetry. Implications on the accuracy of confrontation visual field testing.

PURPOSE: To evaluate the accuracy of confrontation visual field testing with regard to the density of the visual field defect and its location in the peripheral visual field. METHODS: A prospective comparison of confrontation visual field testing with full-threshold Humphrey automated static perimetry C24-2 or C30-2 was conducted at a university eye center over a 3-month period. Seventy-two patients with a variety of neurologic and ophthalmologic conditions underwent confrontation visual field testing and automated perimetry as a part of their evaluation. One visual field from each patient was analyzed for this study. RESULTS: Confrontation visual field testing yielded an overall sensitivity for detecting an abnormal visual field (full-field analysis) of 63%, when sensitivity of confrontation testing rested on the detection of just one abnormal quadrant. The sensitivity of confrontation testing varied depending on the type of visual field loss present: 51% for arcuate scotomas, 67% for visual field constriction, 78% for altitudinal scotomas, and 90% for hemianopias. The sensitivity of detecting abnormal visual field quadrants, rather than the full-field analysis, was, however, poor at 38%. The sensitivity of confrontation testing was lower for superior quadrant defects and higher for inferior quadrant defects. The estimated probability of detecting an abnormal visual field quadrant occurring at a -26-decibel sensitivity loss from age-matched healthy patients for superior quadrant defects and a -19-decibel sensitivity loss for inferior quadrant defects was 50%. The increased sensitivity noted for visual field defects and for inferior quadrant defects appears to be related, in part, to the density of the visual field loss present. CONCLUSION: Confrontation visual field testing is relatively insensitive unless a moderate to dense defect is present, and as such is a poor screening test. However, when visual field defects are identified with confrontation visual field testing, the defects often are real as per the high specificity (97%) and high positive predictive value (96%).

Adult↗
PubMed1996

Visual-spatial deficits expalin visual symptoms in Alzheimer's disease.

PURPOSE: To determine whether the visual symptoms of patients with Alzheimer's disease are related to visual-spatial dysfunction. METHODS: We administered a test battery modified from existing neuropsychometric materials that taxed visual-spatial skills, form identification, color vision, and visual memory. We tested 14 patients with Alzheimer's disease who had visual symptoms prominent enough to prompt ophthalmologic consultation, 11 patients with Alzheimer's disease who lacked such visual symptoms, and a control group of 53 subjects without Alzheimer's disease. The groups with Alzheimer's disease were matched for Wechsler Adult Intelligence Scale-Revised scores. RESULTS: Patients with Alzheimer's disease who had prominent visual symptoms differed significantly from those without prominent visual symptoms only in their relatively poor visual-spatial test scores. CONCLUSIONS: Visual symptoms in Alzheimer's disease are related primarily to visual-spatial deficits. These findings are consistent with previous evidence that patients with Alzheimer's disease who have prominent visual symptoms have accentuated histologic and metabolic abnormalities in the parieto-occipital regions known to process visual-spatial information. The findings support the view that pathways mediating visual-spatial and form identification are at least partially segregated in the brain, and emphasize that tests used to screen visually symptomatic patients with Alzheimer's disease will be more effective if they prominently assess visual-spatial skills.

Aged↗
PubMed2005

Visual search improvement in hemianopic patients after audio-visual stimulation.

One of the most effective techniques in the rehabilitation of visual field defects is based on implementation of oculomotor strategies to compensate for visual field loss. In the present study we develop a new rehabilitation approach based on the audio-visual stimulation of the visual field. Since it has been demonstrated that audio-visual interaction in multisensory neurons can improve temporally visual perception in patients with hemianopia, the aim of the present study was to verify whether a systematic audio-visual stimulation might induce a long-lasting amelioration of visual field disorders. Eight patients with chronic visual field defects were trained to detect the presence of visual targets. During the training, the visual stimulus could be presented alone, i.e. unimodal condition, or together with an acoustic stimulus, i.e. crossmodal conditions. In the crossmodal conditions, the spatial disparity between the visual and the acoustic stimuli were systematically varied (0, 16 and 32 degrees of disparity). Furthermore, the temporal interval between the acoustic stimulus and the visual target in the crossmodal conditions was gradually reduced from 500 to 0 ms. Patients underwent the treatment for 4 h daily, over a period of nearly 2 weeks. The results showed a progressive improvement of visual detections during the training and an improvement of visual oculomotor exploration that allowed patients to efficiently compensate for the loss of vision. More interesting, there was a transfer of treatment gains to functional measures assessing visual field exploration and to daily-life activities, which was found stable at the 1 month follow-up control session. These findings are very promising with respect to the possibility of taking advantage of human multisensory capabilities to recover from unimodal sensory impairments.

Acoustic Stimulation↗
PubMed1999

Creation and testing of a practical visual function assessment for use in Africa: correlation with visual acuity, contrast sensitivity, and near vision in Malawian adults.

AIM: To develop and test a practical visual function assessment for use in developing countries. METHODS: Using focus group discussions and interviews with eyecare workers and low vision specialists in Malawi, 13 questions related to visual characteristics of activities of daily living were designed. Patients presenting to an eye clinic were recruited and interviewed. Visual acuity, near vision, and contrast sensitivity were measured. Analysis sought to determine the degree of correlation between the vision indices and visual function. RESULTS: The visual function questionnaire was easy to administer. Visual function correlated with visual acuity, contrast sensitivity, near vision, and patient reported visual problem. People with a higher frequency of "not applicable" responses had lower visual function scores. Multivariate modelling revealed that visual acuity and number of questions felt to be applicable were independently associated with visual function. Reducing the questionnaire to nine questions did not affect the degree of correlation with any of the visual indices. CONCLUSION: The authors' visual function assessment correlates well with different measures of visual acuity. People with reduced vision for a prolonged period may no longer consider doing certain tasks and the number of questions considered appropriate by an individual may be an additional measure of visual function. Assessment of visual function by health workers may be a valuable tool in improving surgical uptake by encouraging both health personnel and patients to recognise that they have difficulties undertaking activities of daily living as well as a measure of monitoring and evaluating cataract outcomes.

Contrast Sensitivity↗
PubMedDate not supplied

The relationship between visual disability and visual scores in patients with retinitis pigmentosa.

PURPOSE: To evaluate the relationship between visual disability and visual scores in patients with retinitis pigmentosa. METHODS: The relationship between visual disability and visual scores (visual acuity and visual field) was investigated in 93 patients with retinitis pigmentosa. The visual disability of each patient was evaluated using a questionnaire (a total of 35 questions, in 7 sections, regarding daily life). The reproducibility and validity of the data obtained by the questionnaire had been established by a similar investigation in glaucoma patients. Mean (+/-SD) age of patients was 52.6 +/- 15.1 years, the mean visual acuity of the logarithm of the minimum angle of resolution (log10MAR) was 0.5 +/- 0.4, and the mean deviation of visual field with the Humphrey Field Analyzer program 30-2 was -22.0 +/- 10.9 dB. RESULTS: The visual acuity of log10MAR in the better eye (r = 0.66 to 0.81) and the mean sensitivity within the central 10 degrees of the visual field (r = -0.76 to -0.62) had a definite relationship to the visual disability index of each section and their sum (P < .0001). This relationship was also confirmed in multiple regression analysis, which showed a high correlation coefficient (R2 = 0.57 to 0.77, P < .0001). CONCLUSIONS: The retinal sensitivity within the central 10 degrees and the visual acuity of log10MAR in the better eye had a significant influence on a patient's daily life. We suggest that in patients with retinitis pigmentosa, visual disability in daily life can be precisely evaluated with the retinal sensitivity within the central 10 degrees and the visual acuity in the logarithm of the minimum angle of resolution in the better eye.

Female↗
PubMed2004

The impact of visual impairment on self-reported visual functioning in Latinos: The Los Angeles Latino Eye Study.

OBJECTIVE: To assess the association between presenting binocular visual acuity (VA) and self-reported visual function as measured by the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25). DESIGN: A population-based, prevalence study of eye disease in Latinos 40 years and older residing in La Puente, California (Los Angeles Latino Eye Study [LALES]). PARTICIPANTS: Six thousand three hundred fifty-seven Latinos 40 years and older from 6 census tracts in La Puente. METHODS: All participants completed a standardized interview, including the NEI-VFQ-25 to measure visual functioning, and a detailed eye examination. Two definitions of visual impairment were used: (1) presenting binocular distance VA of 20/40 or worse and (2) presenting binocular distance VA worse than 20/40. Analysis of variance was used to determine any systematic differences in mean NEI-VFQ-25 scores by visual impairment. Regression analyses were completed (1) to determine the association of age, gender, number of systemic comorbidities, depression, and VA with self-reported visual function and (2) to estimate a visual impairment-related difference for each subscale based on differences in VA. MAIN OUTCOME MEASURES: The NEI-VFQ-25 scores in persons with visual impairment. RESULTS: Of the 5287 LALES participants with complete NEI-VFQ-25 data, 6.3% (including 20/40) and 4.2% (excluding 20/40) were visually impaired. In the visually impaired participants, the NEI-VFQ-25 subscale scores ranged from 46.2 (General Health) to 93.8 (Color Vision). In the regression model, only VA, depression, and number of comorbidities were significantly associated with all subscale scores (R(2) ranged from 0.09 for Ocular Pain to 0.33 for the composite score). For 9 of 11 subscales, a 5-point change was equivalent to a 1- or 2-line difference in VA. Relationships were similar regardless of the definition of visual impairment. CONCLUSION: In this population-based study of Latinos, the NEI-VFQ-25 was sensitive to differences in VA. A 5-point difference on the NEI-VFQ-25 seems to be a minimal criterion for a visual impairment-related difference. Self-reported visual function is essentially unchanged if the definition of visual impairment includes or excludes a VA of 20/40.

Adult↗
PubMed1999

[The relationships between visual disability and visual scores in patients with retinitis pigmentosa].

PURPOSE: To evaluate the relationship between visual disability and visual scores in patients with retinitis pigmentosa. METHODS: The relationship between visual disability and visual scores (visual acuity and visual field) were investigated in 93 patients with retinitis pigmentosa. The visual disability of each patient was evaluated using a questionnaire (a total of 35 questions in 7 sections regarding daily life). Reproducibility and validity of the questionnaire had been established by an investigation in glaucoma patients. The mean (+/- standard deviation) age of patients was 52.6 +/- 15.1 years, the mean visual acuity (log10 MAR) was 0.6 +/- 0.4, and the mean deviation of visual field with Humphrey program 30-2 was -21.1 +/- 10.0 dB. RESULTS: The visual acuity in the better eye (r = 0.66-0.81) and the mean sensitivity within the central 10 degrees of the visual field (r = -0.76(-)-0.62) had a definite relationship to the visual disability index of each section (section DI) and their sum (total DI) (p < .0001). This relationship was also confirmed in stepwise multiple linear regression analysis which showed a high correlation coefficient (R2 = 0.57-0.77, p < .0001). CONCLUSIONS: Besides the visual acuity, the mean sensitivity within the central 10 degrees of the visual field is important in evaluating the visual disability of patients with retinitis pigmentosa.

Adult↗
PubMed2004

[Grouping of observer's visual characteristics on the basis of difference in the criteria of visual detection and selection of the fittest clustering method:verification of observer's group with radiologist-like visual characteristics].

Various clustering methods are used in cluster analyses, with each clustering method demonstrating unique advantages. Therefore, it is important to make the best use of the advantages each method provides. We have recognized that it is necessary in the evaluation of X-ray images to classify observers quantitatively according to visual characteristics (grouping of observers) and have clustered observers using the UPGMA method, which is one of the clustering methods. We found that the observers were clustered into two different groups, one with radiologist-like characteristics and the other with medical physicist-like characteristics. Furthermore, we suggested that the group with radiologist-like characteristics was suitable for QC of X-ray images. However, it is doubtful whether the UPGMA method is most suitable for the grouping of observers. In this work we clustered observers using various clustering methods and examined the most suitable method for the evaluation of X-ray images. The results showed that the ward method was least suitable for the grouping of observers, and they were distinctly grouped into two different categories by using a further method.

Cluster Analysis↗
PubMed1995

Grating visual acuity with Teller cards compared with Snellen visual acuity in literate patients.

OBJECTIVE: To determine the usefulness of Teller Acuity Cards for detecting three levels of vision deficit, the cutoff for amblyopia (20/40 or poorer), vision impairment (20/70), or legal blindness (20/200). DESIGN: We compared grating visual acuity with the Teller cards with Snellen visual acuity (our gold standard) in 69 literate patients with amblyopia or other cause of vision loss in a prospective masked study. RESULTS: Teller card visual acuity and distance Snellen visual acuity correlated significantly (r = .508, P < .001); however, Teller card visual acuity explained only 26% of the variation in distance Snellen visual acuity. Teller card visual acuity had a low sensitivity for detecting vision deficit of 20/40 or poorer (58%), vision deficit of 20/70 or poorer (39%), or legal blindness (24%), but somewhat more accurately reflected near Snellen visual acuity than distance visual Snellen acuity. Teller cards had a higher positive predictive value--80% for 20/70 visual acuity and 43% for legal blindness, as determined by near Snellen visual acuity. Specificity of Teller cards was 88% for detecting visual acuity loss of 20/70 and 98% for legal blindness. Negative predictive value of Teller cards for detecting visual acuity loss of 20/70 was 50% and for legal blindness was 71%. CONCLUSIONS: Teller Acuity Cards may underestimate the presence of amblyopia of all types, legal blindness, and a specified level of vision impairment (20/70). Even in the presence of normal visual acuity measurements with Teller cards, significant visual loss as assessed by standard Snellen optotypes may be anticipated in many patients.

Adolescent↗
PubMed1996

Visual acuity and the causes of visual loss in Australia. The Blue Mountains Eye Study.

BACKGROUND: The Blue Mountains Eye Study is a population-based study of vision and the causes of visual impairment and blindness in a well-defined urban, Australian population 49 years of age and older. METHODS: The logarithm of the minimum angle of resolution (logMAR) visual acuity was measured before and after refraction in 3647 persons, representing an 88% response rate in two postcode areas in the Blue Mountains area, west of Sydney. RESULTS: Refraction improved visual acuity by one or more lines in 45% of participants and by three or more lines in 13%. Visual impairment (visual acuity 20/40 or worse in the better eye) was found in 170 participants (4.7%). Mild visual impairment (Snellen equivalent 20/40 to 20/60 in the better eye) was found in 3.4% moderate visual impairment (20/80 to 20/160 in the better eye) in 0.6%, and severe visual impairment or blindness (20/200 or worse in the better eye) in 0.7%. Visual impairment increased with age from 0.8% of persons 49 to 54 years of age to 42% of persons 85 years of age or older. Visual impairment was significantly more frequent in females at all ages. Among persons with severe visual impairment, 79% were female. After adjusting for age, females were less likely to achieve 20/20 best-corrected visual acuity than males (odds ratio, 0.57; confidence interval, 0.48-0.66). After adjusting for age and sex, no association was found between visual acuity and socioeconomic status. Age-related macular degeneration was the cause of blindness in 21 of the 24 persons with corrected visual acuity of 20/200 or worse. CONCLUSION: Increasing age and female sex were independent predictors of visual impairment.

Adult↗
PubMed2006

Association between visual impairment and patient-reported visual disability at different stages of cataract surgery.

PURPOSE: To evaluate the association between visual impairment (visual acuity, contrast sensitivity, stereopsis) and patient-reported visual disability at different stages of cataract surgery. METHODS: A cohort of 104 patients aged 60 years and over with bilateral cataract was assessed preoperatively, after first-eye surgery (monocular pseudophakia) and after second-eye surgery (binocular pseudophakia). Partial correlation coefficients (PCC) and linear regression models were calculated. RESULTS: In patients with bilateral cataracts, visual disability was associated with visual acuity (PCC = -0.30) and, to a lesser extent, with contrast sensitivity (PCC = 0.16) and stereopsis (PCC = -0.09). In monocular and binocular pseudophakia, visual disability was more strongly associated with stereopsis (PCC = -0.26 monocular and -0.51 binocular) and contrast sensitivity (PCC = 0.18 monocular and 0.34 binocular) than with visual acuity (PCC = -0.18 monocular and -0.18 binocular). Visual acuity, contrast sensitivity and stereopsis accounted for between 17% and 42% of variance in visual disability. CONCLUSIONS: The association of visual impairment with patient-reported visual disability differed at each stage of cataract surgery. Measuring other forms of visual impairment independently from visual acuity, such as contrast sensitivity or stereopsis, could be important in evaluating both needs and outcomes in cataract surgery. More comprehensive assessment of the impact of cataract on patients should include measurement of both visual impairment and visual disability.

Aged↗
PubMed2004

Integrated visual fields: a new approach to measuring the binocular field of view and visual disability.

BACKGROUND: We have developed a method of quantifying the central binocular visual field by merging results from monocular fields (Integrated visual field). This study aims to compare the new measure with the binocular Esterman visual field test in identifying patients with self-reported visual disability. METHODS: Forty-eight patients with glaucoma each recorded Humphrey 24-2 fields for both eyes and an Esterman on the same day, and each completed a binary forced-choice questionnaire relating to perceived visual disability. Computer software merged sensitivity values from monocular fields to generate an integrated visual field and a related score of the number of defects at the <10 dB and <20 dB level. Receiver operating characteristic (ROC) analysis was used to compare the integrated visual field score and the Esterman disability score with individual responses to the questions on perceived difficulty with visual tasks. RESULTS: Comparison of areas under ROC curves revealed that a score based on the integrated visual field was generally better (median area: 0.79) than Esterman scores (median area: 0.70) in classifying patients with or without a self-reported perceived difficulty with visual tasks. CONCLUSIONS: The integrated visual field offers a rapid assessment of a glaucoma patient's binocular visual field without extra perimetric testing. As compared to an actual binocular field test (Esterman), the integrated visual field provides a better prediction of a glaucoma patient's perceived inability to perform certain visual tasks.

Adult↗
PubMed1996

Visual impairment, visual functioning, and quality of life assessments in patients with glaucoma.

BACKGROUND/PURPOSE: To determine the relation between visual impairment, visual functioning, and the global quality of life in patients with glaucoma. METHODS: Visual impairment, defined with the American Medical Association Guides to the Evaluation of Permanent Impairment; visual functioning, measured with the VF-14 and the Field Test Version of the National Eye Institute-Visual Functioning Questionnaire (NEI-VFQ); and the global quality of life, assessed with the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36), were determined in 147 consecutive patients with glaucoma. RESULTS: None of the SF-36 domains demonstrated more than a weak correlation with visual impairment. The VF-14 scores were moderately correlated with visual impairment. Of the twelve NEI-VFQ scales, distance activities and vision specific dependency were moderately correlated with visual impairment. Of the twelve NEI-VFQ scales, distance activities and vision specific dependency were moderately correlated with visual field impairment; vision specific social functioning, near activities, vision specific role difficulties, general vision, vision specific mental health, color vision, and driving were modestly correlated; visual pain was weakly correlated; and two were not significantly correlated. Correcting for visual actuity weakened the strength of the correlation coefficients. CONCLUSIONS: The SF-36 is unlikely to be useful in determining visual impairment in patients with glaucoma. Based on the moderate correlation between visual field impairment and the VF-14 score, this questionnaire may be generalizable to patients with glaucoma. Several of the NEI-VFQ scales correlate with visual field impairment scores in patients with a wide range of glaucomatous damage.

Adolescent↗