Biomedical subjects

P A Sample

Publications and source records attributed to P A Sample.

At least 19 recordsLinked to original sources

PubMed2001

Relationship between visual field testing and scanning laser polarimetry in patients with a large cup-to-disk ratio.

PURPOSE: To determine the relationship between quantitative nerve fiber layer measurements and visual field testing in patients with large cup-to-disk ratios. METHODS: Seventy-six patients with vertical cup-to-disk ratios by contour of at least 0.8 on stereoscopic photographs and 50 normal subjects were included. One eye was randomly selected for study. All patients underwent standard achromatic automated perimetry, short-wavelength automated perimetry, and retinal nerve fiber layer measurements with scanning laser polarimetry. Analysis of variance was used to evaluate differences between the subject groups. Significance of pairwise comparisons was determined using the Tukey-Kramer multiple comparison test. RESULTS: Statistically significant differences in nerve fiber layer measurements between patients with large cup-to-disk ratios and both abnormal standard achromatic automated perimetry and short-wavelength automated perimetry (n = 22) and patients with large cup-to-disk ratios and both normal standard achromatic automated perimetry and short-wavelength automated perimetry (n = 42) were found for superior nasal ratio, maximum modulation, ellipse modulation, and the linear discriminant function (Tukey-Kramer less than.05). There was no significant difference in patients with abnormal short-wavelength automated perimetry only (n = 9) as compared with patients with both normal standard achromatic automated perimetry and short-wavelength automated perimetry and patients with both abnormal standard achromatic automated perimetry and short-wavelength automated perimetry. Statistically significant differences between the normal subjects and patients with large cup-to-disk ratios and both abnormal standard achromatic automated perimetry and short-wavelength automated perimetry were found for all retinal nerve fiber layer parameters, with the exception of symmetry, superior ratio, and inferior ratio. CONCLUSION: Our results show considerable overlap in nerve fiber layer measurements in eyes with large cup-to-disk ratio and abnormal visual fields as compared with eyes with large cup-to-disk ratios and normal visual fields. This may limit the clinical usefulness of scanning laser polarimetry for detection of early glaucoma in patients with large cup-to-disk ratios. Longitudinal studies are needed to determine if patients with large cup-to-disk ratios with normal standard achromatic automated perimetry and abnormal short-wavelength automated perimetry subsequently develop standard achromatic automated perimetry defects and if scanning laser polarimetry can concurrently detect progression of nerve fiber layer damage.

Aged↗

PubMed2001

What does functional testing tell us about optic nerve damage?

Information from different regions of the visual field travels through specific bundles of retinal ganglion cell axons. This visual information is disrupted in patients with glaucoma, and the effects can be seen in measurements of the visual field and optic nerve. Typical shapes and sizes of glaucomatous field defects result from damage to these nerve fiber bundles at the level of the optic disk, and we have identified specific patterns of progression. These patterns apply to the visual function-specific field tests that are designed to indirectly assess sub-populations of retinal ganglion cells. The rationale for these tests is described. An argument for the importance of using visual function techniques to assess progression in an individual patient is given.

Disease Progression↗

PubMed2001

Functional assessment of glaucoma.

Several studies have correlated the location of visual field defect on some of these newer tests to location of optic nerve damage with good results. In addition, there is an important and direct relationship between the psychophysical measures of visual function and location of damage. When a given individual had vision loss on more than one test, the same area of the visual field is affected. In addition, as soon as a repeatable defect is identified on perimetry, progression of the defect on later fields occurs within or adjacent to the initially identified area. These findings have significant implications for the care and follow-up of patients with glaucoma. Using these more sensitive tests has improved greatly our detection of early glaucomatous damage. Follow-up testing that concentrates the evaluation to areas already damaged should improve greatly our ability to identify true change from the significant physiologic variability present in glaucoma.

Glaucoma↗

PubMed2001

Detecting early glaucoma by assessment of retinal nerve fiber layer thickness and visual function.

PURPOSE: To compare the abilities of scanning laser polarimetry (SLP), optical coherence tomography (OCT), short-wavelength automated perimetry (SWAP), and frequency-doubling technology (FDT) perimetry to discriminate between healthy eyes and those with early glaucoma, classified based on standard automated perimetry (SAP) and optic disc appearance. To determine the agreement among instruments for classifying eyes as glaucomatous. METHODS: One eye of each of 94 subjects was included. Healthy eyes (n = 38) had both normal-appearing optic discs and normal SAP results. Glaucoma by SAP (n = 42) required a repeatable abnormal result (glaucoma hemifield test [GHT] or corrected pattern standard deviation [CPSD] outside normal limits). Glaucoma by disc appearance (n = 51) was based on masked stereoscopic photograph evaluation. Receiver operating characteristic (ROC) curve areas, sensitivities, and specificities were calculated for each instrument separately for each diagnosis. RESULTS: The largest area under the ROC curve was found for OCT inferior quadrant thickness (0.91 for diagnosis based on SAP, 0.89 for diagnosis based on disc appearance), followed by the FDT number of total deviation plot points of < or =5% (0.88 and 0.87, respectively), SLP linear discriminant function (0.79 and 0.81, respectively), and SWAP PSD (0.78 and 0.76, respectively). For diagnosis based on SAP, the ROC curve area was significantly larger for OCT than for SLP and SWAP. For diagnosis based on disc appearance, the ROC curve area was significantly larger for OCT than for SWAP. For both diagnostic criteria, at specificities of > or =90% and > or =70%, the most sensitive OCT parameter was more sensitive than the most sensitive SWAP and SLP parameters. For diagnosis based on SAP, the most sensitive FDT parameter was more sensitive than the most sensitive SLP parameter at specificities of > or =90% and > or =70% and was more sensitive than the most sensitive SWAP parameter at specificity of > or =70%. For diagnosis based on disc appearance at specificity of > or =90%, the most sensitive FDT parameter was more sensitive than the most sensitive SWAP and SLP parameters. At specificity > or = 90%, agreement among instruments for classifying eyes as glaucomatous was poor. CONCLUSIONS: In general, areas under the ROC curve were largest (although not always significantly so) for OCT parameters, followed by FDT, SLP, and SWAP, regardless of the definition of glaucoma used. The most sensitive OCT and FDT parameters tended to be more sensitive than the most sensitive SWAP and SLP parameters at the specificities investigated, regardless of diagnostic criteria.

Diagnostic Techniques, Ophthalmological↗

PubMed2000

Short-wavelength automated perimetry and standard perimetry in the detection of progressive optic disc cupping.

OBJECTIVE: To compare progression in short-wavelength automated perimetry (SWAP) and white-on-white (standard) perimetry in eyes with progressive glaucomatous changes of the optic disc detected by serial stereophotographs. METHODS: Forty-seven glaucoma patients with at least 2 disc stereophotographs more than 2 years apart, along with standard perimetry and SWAP examinations within 6 months of each disc photo of the same eye, were included in the study. The mean follow-up time was 4.1 years (range, 2.0-8.9 years). Baseline and follow-up stereophotographs were then graded and compared for the presence of progression. Progression in standard perimetry and SWAP, using the Advanced Glaucoma Intervention Study scoring system and a clinical scoring system, was compared between eyes with progressive change on stereophotographs and those without. RESULTS: Twenty-two of 47 eyes showed progressive change by stereophotographs. There was a statistically significant difference in the mean change in Advanced Glaucoma Intervention Study scores for both standard perimetry (P<.004) and SWAP (P<.001) between the progressed and nonprogressed groups. The sensitivity, specificity, and area under the receiver operator characteristic curve were higher using SWAP than standard perimetry when evaluated by either algorithm. This was statistically significant only in the area under the receiver operator characteristic curve for the Advanced Glaucoma Intervention Study scoring system (P =.04). CONCLUSIONS: Short-wavelength automated perimetry identified more patients than standard perimetry as having progressive glaucomatous changes of the optic disc. Compared with standard perimetry, SWAP may improve the detection of progressive glaucoma. Arch Ophthalmol. 2000;118:1231-1236

Aged↗

PubMed2000

Comparison of long-term variability for standard and short-wavelength automated perimetry in stable glaucoma patients.

PURPOSE: To quantify and compare, on a point-by-point basis, the long-term variability of standard and short-wavelength automated perimetry in a group of stable glaucoma patients. METHODS: From a group of 53 glaucoma patients experienced in visual field testing, we identified one eye, randomly chosen, from each of 25 glaucoma patients whose condition was found to be stable, based on both standard and short-wavelength automated perimetry visual field criteria. On each of three visits during a period of up to 3 months, each patient performed one standard and one short-wavelength automated perimetry 24-2 visual field in a random order on a Humphrey visual field analyzer. The long-term variability (also referred to as test-retest variability) was defined as the SD of the three threshold decibel values at each test location. The long-term variability for each test point (mean +/- SD) was determined separately for both standard visual fields and short-wavelength automated perimetry. RESULTS: With all 52 test locations of the 24-2 field averaged, the global long-term variability, mean (+/- SD) for standard visual fields and short-wavelength automated perimetry was 2.37 +/- 2.03 dB (95% confidence interval, 2.26-2.48 dB) and 2.92 +/- 2.03 dB (95% confidence interval, 2.81-3.03 dB), respectively (P <.0001). In 16 of the 52 visual field locations, long-term variability on short-wavelength automated perimetry was significantly higher than long-term variability on standard visual fields. In addition, the long-term variability increased with greater distance from the point of fixation for both standard visual fields and short-wavelength automated perimetry. The long-term variability decreased closer to fixation, more for standard visual fields than for short-wavelength automated perimetry. CONCLUSIONS: In a group of stable glaucoma patients, mean long-term variability was 0.55 dB higher for short-wavelength automated perimetry than for standard visual fields. This needs to be taken into consideration when serial visual fields are evaluated for change.

Adult↗

PubMed2000

Short-wavelength automated perimetry: it's role in the clinic and for understanding ganglion cell function.

Short-wavelength automated perimetry (SWAP) is a more sensitive test than standard achromatic perimetry for early loss of vision due to glaucoma and other ocular and neurological diseases. SWAP is also more successful for detecting changes in vision as glaucoma progresses. Results from various visual function-specific tests, including SWAP, suggest that there are individual differences in ocular hypertensive and glaucoma eyes in the subtype of ganglion cell first affected. However, the disease targets the same retinal area for all function-specific tests that show a deficit in a given individual. Psychophysical tests of vision are critical to understand glaucoma's effect on retinal ganglion cells, to verify the success or failure of treatment including new neuroprotective agents, and to determine the relationship of genetic markers for glaucoma to the presence and progress of the disease.

Glaucoma↗

PubMed2000

Comparative study between pointwise and ranked threshold distribution analyses of change in serial fields for short-wavelength automated perimetry.

PURPOSE: To assess the validity of ranked threshold distribution (RTD) analysis for longitudinal evaluation of short-wavelength automated perimetry (SWAP). METHODS: Eighty-five patients with glaucoma and with three or more SWAP results were examined. An additional 20 patients with glaucoma and 3 stable standard automated visual fields and 3 stable SWAP fields were assessed to calculate variability. An RTD curve was created. For RTD analysis and pointwise analysis, values that decreased more than the SWAP variability were considered to have worsened. Using pointwise analysis, four groups were defined: no change (without any 2 contiguous points decreasing in threshold); focal change (at least 2 contiguous points with decreased thresholds in either hemifield); diffuse change (more than 50% of the entire 52 locations with significant decrease in thresholds); and focal and diffuse change (less than 50%, but crossing both hemifields). RESULTS: Using pointwise analysis, 32 (37.6%) patients did not change; 23 (27.1%) patients had focal worsening; 8 (9.4%) patients had diffuse worsening; and 22 (25.9%) patients had focal and diffuse worsening. Significant differences were found among the groups in the number of deteriorating locations (P < 0.0001, analysis of variance). The ranges of deteriorating locations identified by RTD analysis for focal change and diffuse change did not overlap. A significant correlation was found between the numbers of locations with decreased threshold by both analyzes (r2 = 0.83, P < 0.0001). CONCLUSION: For evaluation of possible SWAP progression, RTD analysis is closely related with pointwise analysis and is useful for visualizing a diffuse component of change in the field.

Adult↗

PubMed2000

Visual function-specific perimetry for indirect comparison of different ganglion cell populations in glaucoma.

PURPOSE: To compare short-wavelength automated perimetry, frequency-doubling technology perimetry, and motion-automated perimetry, each of which assesses different aspects of visual function, in eyes with glaucomatous optic neuropathy and ocular hypertension. METHODS: One hundred thirty-six eyes from 136 subjects were evaluated with all three tests as well as with standard automated perimetry. Fields were not used in the classification of study groups to prevent bias, because the major purpose of the study was to evaluate each field type relative to the others. Seventy-one of the 136 eyes had glaucomatous optic neuropathy, 37 had ocular hypertension, and 28 served as age-matched normal control eyes. Glaucomatous optic neuropathy was defined by assessment of stereophotographs. Criteria were asymmetrical cupping, the presence of rim thinning, notching, excavation, or nerve fiber layer defect. Ocular hypertensive eyes had intraocular pressure of 23 mm Hg or more on at least two occasions and normal-appearing optic disc stereophotographs. Criteria for abnormality on each visual field test were selected to approximate a specificity of 90% in the normal eyes. Thresholds for each of the four tests were compared, to determine the percentage that were abnormal within each patient group and to assess the agreement among test results for abnormality, location, and extent of visual field deficit. RESULTS: Each test identified a subset of the eyes with glaucomatous optic neuropathy as abnormal: 46% with standard perimetry, 61% with short-wavelength automated perimetry, 70% with frequency-doubling perimetry, and 52% with motion-automated perimetry. In the ocular hypertensive eyes, standard perimetry was abnormal in 5%, short wavelength in 22%, frequency doubling in 46%, and motion in 30%. Fifty-four percent (38/71) of eyes with glaucomatous optic neuropathy were normal on standard fields. However, 90% were identified by at least one of the specific visual function tests. Combining tests improved sensitivity with slight reductions in specificity. The agreement in at least one quadrant, when a defect was present with more than one test, was very high at 92% to 97%. More extensive deficits were shown by frequency-doubling perimetry followed by short-wavelength automated perimetry, then motion-automated perimetry, and last, standard perimetry. However, there were significant individual differences in which test of any given pairing was more extensively affected. Only 30% (11/37) of the ocular hypertensive eyes showed no deficits at all compared with 71% (20/28) of the control eyes (P < 0.001). CONCLUSIONS: For detection of functional loss standard visual field testing is not optimum; a combination of two or more tests may improve detection of functional loss in these eyes; in an individual, the same retinal location is damaged, regardless of visual function under test; glaucomatous optic neuropathy identified on stereophotographs may precede currently measurable function loss in some eyes; conversely, function loss with specific tests may precede detection of abnormality by stereophotograph review; and short-wavelength automated perimetry, frequency-doubling perimetry, and motion-automated perimetry continue to show promise as early indicators of function loss in glaucoma.

Glaucoma↗

PubMed1999

Achromatic and short-wavelength automated perimetry in patients with glaucomatous large cups.

OBJECTIVE: To evaluate visual function and optic disc features in patients with large cup-disc ratios (C/Ds). METHODS: One eye of 86 patients with vertical C/Ds by contour of at least 0.8, who had undergone both standard achromatic automated perimetry (SAP) and short-wavelength automated perimetry (SWAP) testing, was selected retrospectively. Two masked glaucoma specialists independently graded stereoscopic photographs for vertical C/Ds, rim thinning, notching, excavation, optic disc hemorrhages, and nerve fiber layer defects. Visual fields were classified as abnormal if the glaucoma hemifield test result, corrected pattern standard deviation, or mean deviation was outside age-specific normal limits. Confocal scanning laser ophthalmoscopy was used to determine disc area. RESULTS: SAP and SWAP results were abnormal in 44 (51%) and 52 (60%) of 86 patients, respectively. In patients with normal SAP results, SWAP results were abnormal in 14 (33%) of 42 patients. In patients with normal SWAP results, SAP results were abnormal in 6 (18%) of 34 patients. Small discs are associated with an abnormal SAP result (P = .01) and an abnormal SWAP result (P = .09). An increased vertical C/D greater than the qualifying level of 0.8 was associated with an abnormal SAP or SWAP result (P< or =.001). Rim thinning (P = .01) and disc hemorrhages (P = .04) were associated with an abnormal SAP result. CONCLUSIONS: Many patients with large C/Ds have normal SAP and SWAP results. Compared with SAP, SWAP results were abnormal in a higher percentage of these patients. If a patient has a large C/D and normal SAP results, SWAP testing may detect functional loss earlier. If glaucoma is defined by both structural and functional loss, patients with large vertical C/Ds, normal SAP results, and abnormal SWAP results may have glaucoma. Longitudinal studies are needed to assess this hypothesis and determine whether these patients subsequently develop abnormal SAP results as well.

Adult↗

PubMed1999

The utility of entoptic perimetry as a screening test for cytomegalovirus retinitis.

OBJECTIVE: To determine the sensitivity and specificity of entoptic perimetry as a noninvasive test for detecting retinal damage due to peripheral cytomegalovirus (CMV) retinitis. DESIGN: A masked study comparing entoptic perimetry with fundus photography under 4 experimental conditions (determined by increasing pixel sizes) on 2 separate testing sessions. SETTING: Acquired immunodeficiency syndrome Ocular Research Unit at the University of California, San Diego. PATIENTS: Twenty-four human immunodeficiency virus-positive and 8 human immunodeficiency virus-negative subjects; 21 eyes with documented CMV retinitis, and 26 eyes that were retinitis free. MEASUREMENTS: For each testing session, screening method, and condition, the presence of CMV retinitis was determined for each meridian (i.e., clock hour), each quadrant (consisting of 3 meridians), and each eye (consisting of all meridians); the amount of retinitis was defined as the percentage of meridians or quadrants with CMV retinitis. RESULTS: Entoptic perimetry was as sensitive and specific as fundus photography in determining the presence of CMV retinitis. Determination of the amount of CMV retinitis tended to be underestimated by perimetry for larger pixel sizes. CONCLUSION: Entoptic perimetry may be an effective and inexpensive alternative to fundus photography for CMV retinitis in hospitals and community clinics.

AIDS-Related Opportunistic Infections↗

PubMed1999

Pattern of early visual field loss in HIV-infected patients.

OBJECTIVE: To determine the topographic pattern of visual field loss, if any, and its relationship to the stage of disease in human immunodeficiency virus-positive patients without infectious retinopathy. METHODS: A total of 151 eyes from 81 alert and cooperative patients with human immunodeficiency virus were evaluated with visual field testing. Results were analyzed relative to the associated underlying nerve fiber layer patterns associated with retinal ganglion cell axons as they traverse the retina to the optic nerve. The stage of visual field loss was analyzed relative to the length of survival using Kaplan-Meier survival analysis. RESULTS: No correlation of CD4 cell count with visual field mean defect (r2 = 0.23) or corrected pattern standard deviation (r2 = 0.00) was found. A pattern of visual field loss, consistent with sparing of the papillomacular bundles and associated with damage primarily to the inferior retina external to the posterior pole, was found. Survival analysis indicated a significant difference in time of survival between individuals with normal visual fields and those with a diffuse visual field loss, with a trend to less survival with increasing field loss severity. CONCLUSIONS: These results are consistent with disease at the level of the optic nerve. The relationship of stage of visual field loss to survival has important implications for early detection of field loss and appropriate therapeutic intervention to maintain function and quality of life.

Adult↗

PubMed1999

Relationship between parapapillary atrophy and visual field abnormality in primary open-angle glaucoma.

PURPOSE: To investigate the relationship of parapapillary atrophy measured by confocal scanning laser ophthalmoscopy to visual field sensitivity measured with standard automated perimetry and short-wavelength automated perimetry in patients with primary open-angle glaucoma. METHODS: Forty-seven eyes of 47 primary open-angle glaucoma patients with increased intraocular pressure (> or = 22 mm Hg) were enrolled. Optic nerve head topography and parapapillary atrophy (beta and alpha zones) were assessed by confocal scanning laser ophthalmoscopy. Mean deviation and corrected pattern SD were assessed with standard automated perimetry and short-wavelength automated perimetry. RESULTS: Beta and alpha zones were found in 23 (49%) and 47 (100%) eyes with primary open-angle glaucoma, respectively. The area of beta zone showed significant correlations with MD of standard automated perimetry, corrected pattern SD of standard automated perimetry, and corrected pattern SD of short-wavelength automated perimetry (Spearman r = -0.366, P = .012; r = 0.327, P = .025; and r = 0.436, P = .002, respectively). The area of alpha zone showed a significant correlation with mean deviation of standard automated perimetry (r = -0.378, P = .009). Mean MD of standard automated perimetry, mean corrected pattern SD of standard automated perimetry, and mean corrected pattern SD of short-wavelength automated perimetry were significantly worse in eyes with beta zone than in eyes without beta zone. CONCLUSIONS: Parapapillary atrophy measured by confocal scanning laser ophthalmoscopy, especially beta zone, is associated with glaucomatous visual field loss demonstrated by standard automated perimetry and short-wavelength automated perimetry.

Adult↗

PubMed1999

Parapapillary atrophy in patients with focal visual field loss.

PURPOSE: To examine parapapillary atrophy in normal subjects and patients with primary open-angle glaucoma with focal visual field loss. METHODS: Twenty-nine patients with repeatable early focal visual field loss according to standard automated perimetry (Humphrey program 24-2) and 29 matched (age and disk area) normal subjects were included. Parapapillary atrophy area and optic disk topography were evaluated with a confocal scanning laser ophthalmoscope. The difference in parapapillary atrophy area between normal subjects and patients with glaucoma was examined. Optic disk topography was evaluated by means of the rim-disk area ratio in 36 10-degree sectors and classified into diffuse and focal patterns of neuroretinal rim thinning. In patients with a focal pattern, the locations of rim thinning and parapapillary beta zone atrophy were compared. RESULTS: Beta zone atrophy was detected more frequently in patients with glaucoma (45% [13/29]) than in normal subjects (7% [2/29]), and it was located both superiorly and inferiorly in 92% (12/13) of the glaucoma patients. Alpha zone atrophy was significantly larger in patients with glaucoma than normal subjects (P = .009) but not more frequent (97% [28/29] in both groups). Sixty-one percent (8/13) of glaucoma patients with beta atrophy had diffuse thinning and 31% (4/13) had focal thinning. Eight percent (1/13) did not have neuroretinal rim thinning. In the four patients with both focal rim thinning and beta zone atrophy, the location of rim thinning corresponded to the location of the beta zone atrophy (100% [4/4]). CONCLUSIONS: In patients with early focal glaucomatous visual field loss, the presence and location of parapapillary beta zone atrophy and neuroretinal rim thinning are in good correspondence. Observation of localized parapapillary beta zone atrophy in clinical practice should direct one to more closely examine the optic disk in this region, as it may reveal localized rim thinning in a disk previously considered to be normal. Moreover, diffuse structural change in an eye with only focal functional change, as determined by standard automated perimetry, is consistent with the possibility that structural damage may be more widespread than functional damage in these patients.

Adult↗

PubMed1999

Spatial relationship of motion automated perimetry and optic disc topography in patients with glaucomatous optic neuropathy.

PURPOSE: To compare the spatial relationship of focal motion automated perimetry (MAP) visual field defect with focal defect in optic disc topography. METHODS: Patients (n = 12) with focal MAP visual field loss and focal change in optic disc topography were studied. The MAP visual field was divided into 12 field zones representing retinal nerve fiber layer arcuate bundles. Zones of MAP loss were related to rim area ratio (RAR), which was obtained by dividing the rim area, measured by the Heidelberg Retina Tomograph (HRT; Heidelberg Engineering, Heidelberg, Germany), into 36 10 degrees sectors and then dividing the area of each sector by the total rim area for each subject. Rim area ratio was compared to a normative database (n = 76) to quantify change in optic disc topography. In these same patients, the spatial relationship between standard automated perimetry (SAP) and short-wavelength perimetry (SWAP) and optic disc topography was also assessed. RESULTS: Motion automated perimetry superior visual field zones 14 through 19 were most often associated with a reduction in RAR for inferior sectors 24 through 29, and inferior visual field zones 4 through 7 were most often associated with a reduction in RAR for superior temporal sectors 11 through 16. Similar spatial relationships were found between SWAP and SAP and the RAR. CONCLUSION: Focal MAP visual field loss and focal changes in optic disc topography are spatially related. This relationship is similar to that found between SWAP and SAP with optic disc topography. Focal thinning or notching detected by RAR analysis might be independent of the specific functional test employed.

Glaucoma, Open-Angle↗

PubMed1999

Neuropsychological impairment-associated visual field deficits in HIV infection. HNRC Group. HIV Neurobehavioral Research Center.

PURPOSE: To examine the relationship between loss in peripheral visual sensitivity and neuropsychological functioning in seropositive patients with human immunodeficiency virus (HIV) without infectious retinopathy. METHODS: Subjects carefully screened for retinal disease and well-matched across demographic and medical variables were grouped according to normal (perimetry-nl) versus abnormal (perimetry-abnl) performance on achromatic automated perimetry and short-wavelength automated perimetry, standard clinical ophthalmologic measures of visual function. All subjects completed a detailed neuropsychological test battery and were classified as impaired or unimpaired, globally and across eight neurocognitive domains. Subjects were also classified according to whether they met diagnostic criteria for minor cognitive/motor disorder (MCMD) or HIV-associated dementia (HAD). RESULTS: Visual field loss was associated with lower performance in the abstraction, perceptual-motor, learning, and motor domains. Significant group differences were also found on numerous individual neuropsychological tests. Based on clinical ratings, we found deficits in learning and motor functioning. No perimetry-nl subjects met criteria for MCMD or HAD, whereas 32% of perimetry-abnl subjects met diagnostic criteria for syndromic cognitive disorders (five MCMD and one HAD). In a subset of subjects who underwent a lumbar puncture, there was a trend for the perimetry-abnl group to have a higher concentration of beta2 microglobulin, a marker for central nervous system immune activation. CONCLUSIONS: These results suggest that in some HIV-infected people reduced visual function may be caused by nonretinal disease, and perimetry may present a sensitive measure of HIV-related brain dysfunction.

Adult↗

PubMed1998

Detection of glaucoma with scanning laser polarimetry.

OBJECTIVE: To determine which retinal nerve fiber layer (RNFL) measures obtained with scanning laser polarimetry are most useful in detecting early to moderate glaucomatous visual field loss. SUBJECTS AND METHODS: One eye from 84 healthy individuals and 83 patients with early to moderate glaucomatous visual field loss (167 eyes) was assessed with a scanning laser polarimeter (Laser Diagnostic Technologies, San Diego, Calif). Three separate scans were obtained, and a baseline scan was created and used in the analyses. Integrated software (program GDx, version 1.0.02; Laser Diagnostic Technologies) was evaluated by assessing its sensitivity and specificity for detecting early and moderate glaucomatous visual field loss. Fisher linear discriminant functions also were developed in this population to assess sensitivity and specificity and were compared with the GDx analyses. RESULTS: There were statistically significant differences between the healthy and glaucomatous eyes for 14 of the 15 RNFL measures (P = .001). However, considerable overlap in measurements between groups was found. With the GDx number, the area under the receiver operator characteristic (ROC) curve was 0.78, and the sensitivity and specificity were 82% and 62%, respectively. Applying the best discriminant function using 3 variables (average thickness, ellipse modulation, and average ellipse thickness) to our study population resulted in an area under the ROC curve of 0.89 and a sensitivity and specificity of 74% and 92%, respectively. CONCLUSIONS: A combination of RNFL measures obtained using the scanning laser polarimeter improved the ability to differentiate between healthy eyes and eyes with early and moderate glaucomatous visual field loss. Analyses using GDx software did not differentiate between healthy and glaucomatous eyes as well as the discriminant analysis function did.

Aged↗

PubMed1998

Motion automated perimetry identifies early glaucomatous field defects.

OBJECTIVE: To determine if motion automated perimetry can identify early glaucomatous visual field defects in patients with suspected glaucoma (by disc), those with ocular hypertension, and those with primary open-angle glaucoma. METHODS: Motion automated perimetry, a foveally centered motion test, and standard visual field tests were conducted on one randomly selected eye of normal patients (n = 38), patients with suspected glaucoma (by disc) (n = 28), patients with ocular hypertension (n = 18), and patients with primary open-angle glaucoma (n = 21). Subjects' performance on both motion tests were compared with their performance on standard perimetry. RESULTS: Perimetric motion thresholds significantly distinguished the groups (P< or =.001), while the foveally centered motion test was unable to separate them (P< or =.32). Of the total patients, 90.5% of those with glaucoma, 39.3% of those with suspected glaucoma, 27.8% of those with ocular hypertension, and 5.3% of the normal subjects had abnormal results on motion automated perimetry testing. Perimetric motion thresholds were significantly correlated with standard visual field thresholds (P< or =.001). CONCLUSION: Motion automated perimetry identifies visual field defects in patients who already show standard visual field loss as well as in a moderate percentage of those with suspected glaucoma and ocular hypertension, indicating that the testing of discrete locations might be necessary for increased diagnostic utility.

Aged↗