1
|
Pang R, Peng J, Cao K, Sun Y, Pei XT, Yang D, Lu ZL, Wang N. Association between contrast sensitivity function and structural damage in primary open-angle glaucoma. Br J Ophthalmol 2024; 108:801-806. [PMID: 37423645 DOI: 10.1136/bjo-2023-323539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 06/17/2023] [Indexed: 07/11/2023]
Abstract
AIMS To evaluate the association between contrast sensitivity function (CSF) and glaucomatous structural damage in primary open-angle glaucoma (POAG). METHODS A cross-sectional study was performed with 103 patients (103 eyes) aged 25-50 years who had POAG without any other ocular disease. CSF measurements were obtained by the quick CSF method, a novel active learning algorithm that covers 19 spatial frequencies and 128 contrast levels. The peripapillary retinal nerve fibre layer (pRNFL), macular ganglion cell complex (mGCC), radial peripapillary capillary (RPC) and macular vasculature were measured by optical coherence tomography and angiography. Correlation and regression analyses were used to assess the association of area under log CSF (AULCSF), CSF acuity and contrast sensitivities at multiple spatial frequencies with structural parameters. RESULTS AULCSF and CSF acuity were positively associated with pRNFL thickness, RPC density, mGCC thickness and superficial macular vessel density (p<0.05). Those parameters were also significantly associated with contrast sensitivity at 1, 1.5, 3, 6, 12, 18 cycles per degree spatial frequencies (p<0.05) and, the lower the spatial frequency, the higher the correlation coefficient. RPC density (p=0.035, p=0.023) and mGCC thickness (p=0.002, p=0.011) had significant predictive value for contrast sensitivity at 1 and 1.5 cycles per degree, with adjusted R 2 of 0.346 and 0.343, respectively. CONCLUSIONS Full spatial frequency contrast sensitivity impairment, most notably at low spatial frequencies, is a characteristic change in POAG. Contrast sensitivity is a potential functional endpoint for the measurement of glaucoma severity.
Collapse
Affiliation(s)
- Ruiqi Pang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Jieting Peng
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Eye College of Chengdu University of TCM, Chengdu, Sichuan, China
| | - Kai Cao
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Yunxiao Sun
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Xue-Ting Pei
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Diya Yang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Zhong-Lin Lu
- Division of Arts and Sciences, NYU Shanghai, Shanghai, China
- Center for Neural Science and Department of Psychology, New York University, New York, New York, USA
- NYU-ECNU Institute of Brain and Cognitive Neuroscience, Shanghai, China
| | - Ningli Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| |
Collapse
|
2
|
Bae YH, Choi DG. Changes in contrast sensitivity after surgery for intermittent exotropia. Sci Rep 2022; 12:6542. [PMID: 35449175 PMCID: PMC9023475 DOI: 10.1038/s41598-022-10399-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 03/24/2022] [Indexed: 11/09/2022] Open
Abstract
To determine whether intermittent exotropia (IXT) surgery affects contrast sensitivity (CS), this retrospective study evaluated the changes in monocular and binocular CS and the binocular summation ratio (BSR) quantified as the ratio between the values of the binocular and the better monocular CS score (BSR = binocular CS score/better monocular CS score) after surgery for IXT. The subjects were patients who had undergone IXT-correcting surgery with a postoperative follow-up of > 3 months and had pre- and postoperative records of Mars CS test scores. In total, 64 patients (128 eyes) were evaluated. Both the binocular and monocular CS scores of the operated eyes were significantly worse on postoperative 1 day than the preoperative scores, but they were recovered after 1 week. The monocular CS scores of the operated eyes were significantly worse than those of the non-operated eyes until 1 week. There was no significant difference in monocular CS scores between the one-muscle and two-muscle surgeries and in binocular CS scores between the successful alignment and overcorrection groups even on the first day after surgery. The mean BSR was significantly decreased until postoperative month 1, however, recovered to preoperative levels after month 3. In conclusion, IXT-correcting surgery may temporarily worsen the CS, but it is recovered to preoperative levels. Thus, changes in CS in the immediate postoperative period after strabismus surgery should not be of concern.
Collapse
Affiliation(s)
- Young Hwan Bae
- Department of Ophthalmology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, 665 Shiheongdae-ro, Seoul, 07442, South Korea
| | - Dong Gyu Choi
- Department of Ophthalmology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, 665 Shiheongdae-ro, Seoul, 07442, South Korea.
| |
Collapse
|
3
|
Rao A, Padhy D, Pal A, Roy AK. Visual function tests for glaucoma practice - What is relevant? Indian J Ophthalmol 2022; 70:749-758. [PMID: 35225508 PMCID: PMC9114550 DOI: 10.4103/ijo.ijo_1390_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Glaucoma represents one of the most important ocular diseases causing irreversible ganglion cell death. It is one of the most common causes of visual impairment and morbidity in the elderly population. There are various tests for measuring visual function in glaucoma. While visual field remains the undisputed method for screening, diagnosis, and monitoring disease progression, other tests have been studied for their utility in glaucoma practice. This review discusses some of the commonly used tests of visual function that can be routinely used in clinics for glaucoma management. Among the various modalities of testing visual function in glaucoma, this review highlights the tests that are most clinically relevant.
Collapse
Affiliation(s)
- Aparna Rao
- Department of Glaucoma Services, L. V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Debananda Padhy
- Department of Glaucoma Services, L. V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Anindita Pal
- Department of Glaucoma Services, L. V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| | - Avik Kumar Roy
- Department of Glaucoma Services, L. V. Prasad Eye Institute, Bhubaneswar, Odisha, India
| |
Collapse
|
4
|
Evaluation of the association between macular damage and disability glare in patients with advanced glaucoma. Graefes Arch Clin Exp Ophthalmol 2022; 260:2971-2980. [PMID: 35192030 DOI: 10.1007/s00417-022-05593-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 02/01/2022] [Accepted: 02/10/2022] [Indexed: 11/04/2022] Open
Abstract
PURPOSE This study aimed to investigate the factors associated with disability glare in patients with advanced glaucoma and evaluate the impact of disability glare on the vision-related quality of life. METHODS We prospectively studied 225 eyes (225 patients) with advanced glaucoma. The visual function was evaluated using the 10-2 and 24-2 Humphrey visual field (VF) (Dublin, California) and contrast sensitivity test. Structural parameters were obtained using RTVue optical coherence tomography and angiography (Fremont, California). Significant loss of macular vessel density (mVD) was defined as VD < 30%. Each participant completed the National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ-25) and questions regarding subjective symptoms of glare. RESULTS Fifty-six patients (24.9%) experienced glare and had a lower NEI-VFQ-25 composite score (P = 0.017). The average retinal nerve fiber layer and ganglion cell complex thickness and mean deviation (MD) in the 24-2 VF test were not associated with glare. Significant superior or inferior mVD loss (P < 0.001; odds ratio [OR], 3.45; and 95% confidence interval [CI], 1.83-6.55), lower logarithmic contrast sensitivity at 0.75 cycles/degree (P < 0.001; OR, 0.27; and 95% CI, 0.13-0.56), and worse MD in the 10-2 VF test (P < 0.001; OR, 0.93; and 95% CI, 0.89-0.97) showed an association with glare. CONCLUSION In advanced glaucoma, central VF defect and mVD loss are associated with disability glare, which negatively impacts vision-related quality of life.
Collapse
|
5
|
Jammal AA, Ferreira BG, Zangalli CS, Vianna JR, Thompson AC, Artes PH, Costa VP, Reis ASC. Evaluation of contrast sensitivity in patients with advanced glaucoma: comparison of two tests. Br J Ophthalmol 2020; 104:1418-1422. [PMID: 31974085 DOI: 10.1136/bjophthalmol-2019-315273] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 12/20/2019] [Accepted: 01/10/2020] [Indexed: 11/03/2022]
Abstract
AIMS To evaluate contrast sensitivity (CS) in patients with advanced glaucomatous visual field damage, and to compare two clinical CS tests. METHODS This was a cross-sectional test-retest study. Twenty-eight patients with open-angle glaucoma, visual acuity (VA) better than 20/40 and visual field mean deviation (MD) worse than -15 dB were enrolled. Patients underwent VA, visual field and CS testing with the Pelli-Robson (PR) chart and the Freiburg Visual Acuity and Contrast Test (FrACT). Retest measurements were obtained within 1 week to 1 month. RESULTS Median (IQR) age and MD were 61.5 (55.5 to 69.2) years and -27.7 (-29.7 to -22.7) dB, respectively. Median (IQR) VA was 0.08 logarithm minimum angle of resolution (0.02 to 0.16), corresponding to 20/25 (20/20 to 20/30). Median (IQR) CS was 1.35 (1.11 to 1.51) log units with the PR chart and 1.39 (1.24 to 1.64) log units with FrACT. VA explained less than 40% of the variance in CS (adjusted R2=0.36). CS estimates of both tests were closely related (rho=0.88, p=0.001), but CS was 0.09 log units higher with FrACT compared with the PR chart, and the 95% repeatability intervals (Bland-Altman) were 46% tighter with the PR chart. CONCLUSIONS Despite near-normal VA, almost all patients showed moderate to profound deficits in CS. CS measurement provides additional information on central visual function in patients with advanced glaucoma.
Collapse
Affiliation(s)
- Alessandro A Jammal
- Department of Ophthalmology, Universidade Estadual de Campinas, Campinas, Brazil.,Duke Eye Center, Duke University, Durham, North Carolina, USA
| | - Bruna G Ferreira
- Department of Ophthalmology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Camila S Zangalli
- Department of Ophthalmology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Jayme R Vianna
- Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | - Paul H Artes
- Eye and Vision Research Group, Institute of Health and Community, Plymouth University, Plymouth, UK
| | - Vital P Costa
- Department of Ophthalmology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Alexandre S C Reis
- Department of Ophthalmology, Universidade Estadual de Campinas, Campinas, Brazil
| |
Collapse
|
6
|
Bierings RAJM, Overkempe T, van Berkel CM, Kuiper M, Jansonius NM. Spatial contrast sensitivity from star- to sunlight in healthy subjects and patients with glaucoma. Vision Res 2019; 158:31-39. [PMID: 30721742 DOI: 10.1016/j.visres.2019.01.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Revised: 01/26/2019] [Accepted: 01/30/2019] [Indexed: 02/08/2023]
Abstract
Glaucoma is traditionally considered an asymptomatic disease until later stages. However, questionnaire studies revealed visual complaints related to various tasks, especially under extreme luminance conditions (such as outdoor at night on an unlit road or outside in the sun). We measured contrast sensitivity (CS) over a luminance range of 6 log units spanning the scotopic to photopic range and we aimed (1) to determine whether Weber's law also holds under extremely high luminance conditions and (2) to compare CS as a function of spatial frequency and luminance between glaucoma patients and healthy subjects. We included 22 glaucoma patients and 51 controls, all with normal visual acuity. For the second aim, we used a subgroup of 22 age-similar controls. Vertically oriented sine-wave gratings were generated with a projector-based setup (stimulus size 8x5 degrees). CS was measured monocularly at 1, 3, and 10 cycles per degree (cpd); mean luminance ranged from 0.0085 to 8500 cd/m2. ANOVA was used to analyze the effect of glaucoma, luminance, and spatial frequency on logCS. In controls, Weber's law held for 3 and 10 cpd; for 1 cpd, CS dropped above 1000 cd/m2 (P = 0.003). The logCS versus log luminance curves did not differ grossly between patients and controls (P = 0.14; typically 0-0.2 log units); the difference became larger with decreasing luminance (P = 0.003) but did not depend clearly on spatial frequency (P = 0.27). We conclude that differences between glaucoma and healthy were relatively modest for the spatially redundant, static stimulus as used in the current study.
Collapse
Affiliation(s)
- R A J M Bierings
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - T Overkempe
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - C M van Berkel
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - M Kuiper
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - N M Jansonius
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
| |
Collapse
|
7
|
Senger C, da Silva MJL, De Moraes CG, Messias A, Paula JS. Spatial correlation between localized decreases in exploratory visual search performance and areas of glaucomatous visual field loss. Graefes Arch Clin Exp Ophthalmol 2018; 257:153-160. [PMID: 30368564 DOI: 10.1007/s00417-018-4164-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/29/2018] [Accepted: 10/15/2018] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Visual search is a critical skill for several daily tasks and may be compromised in patients with impaired vision. The objective of this study was to study the relationships between exploratory visual search performance (EVSP) visual field (VF) sensitivity in patients with glaucoma. METHODS Primary open-angle glaucoma patients (POAG; n = 29) and healthy (Control; n = 28) individuals with best corrected visual acuity better than 0.2 logMAR underwent a comprehensive ophthalmological examination, including Humphrey VF tests (24-2 SITA-Standard), and a monocular exploratory visual search digit-based task performed using a software that quantifies the time spent to find a targert on a random array of digits distributed on nine sequential screens. The screens were divided into five areas to topographically match with five VF sectors. RESULTS As expected, POAG eyes had worse VF mean deviation (MD) sensitivity and EVSP than Controls (MD - 8.02 ± 7.88 dB vs - 1.43 ± 1.50 dB, p < 0.0001; and total EVSP time 106.42 ± 59.64 s vs 52.75 ± 19.07 s, p < 0.0001). MD sensitivity of both groups significantly correlated with total EVSP time (POAG r = - 0.45, p = 0.01; and Control r = 0.37, p = 0.049). A significant relationship was observed between EVSP (individual time) and both visual acuity (p = 0.006) and glaucoma diagnosis (p = 0.005). The mean sensitivity of the peripheral VF areas of the POAG group showed significant correlation with the individual search time in the corresponding spatial areas, except in the peripheral superior temporal area (r = - 0.35, p = 0.06). CONCLUSION These data indicate that POAG patients' EVSP is impaired in topographically-correspondent VF areas with sensitivity loss. Visual search may be considered as a measure of impairment of daily activities in glaucoma patients, if further similar tests using binocular conditions corroborate our findings.
Collapse
Affiliation(s)
- Cassia Senger
- Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Ribeirão Preto Medical School- University of São Paulo, Av. Bandeirantes, 3900 - 12°. Andar. Ribeirão Preto, São Paulo, Brazil
| | - Marcelo Jordão Lopes da Silva
- Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Ribeirão Preto Medical School- University of São Paulo, Av. Bandeirantes, 3900 - 12°. Andar. Ribeirão Preto, São Paulo, Brazil
| | - Carlos Gustavo De Moraes
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University Medical Center, New York, NY, USA
| | - André Messias
- Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Ribeirão Preto Medical School- University of São Paulo, Av. Bandeirantes, 3900 - 12°. Andar. Ribeirão Preto, São Paulo, Brazil
| | - Jayter Silva Paula
- Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Ribeirão Preto Medical School- University of São Paulo, Av. Bandeirantes, 3900 - 12°. Andar. Ribeirão Preto, São Paulo, Brazil.
| |
Collapse
|
8
|
Nguyen DT, Fahimi A, Fink W, Nazemi PP, Kim JK, Sadun AA. Novel 3D Computer-Automated Threshold Amsler Grid Visual Field Testing of Scotomas in Patients with Glaucoma. Eur J Ophthalmol 2018; 19:776-82. [DOI: 10.1177/112067210901900515] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Dieuthu T. Nguyen
- Doheny Eye Institute and Keck School of Medicine at the University of Southern California, Los Angeles
| | - Ali Fahimi
- Doheny Eye Institute and Keck School of Medicine at the University of Southern California, Los Angeles
| | - Wolfgang Fink
- Doheny Eye Institute and Keck School of Medicine at the University of Southern California, Los Angeles
- Visual and Autonomous Exploration Systems Research Laboratory, Division of Physics, Mathematics & Astronomy, California Institute of Technology, Pasadena - USA
| | - Paul P. Nazemi
- Doheny Eye Institute and Keck School of Medicine at the University of Southern California, Los Angeles
| | - Janet K. Kim
- Doheny Eye Institute and Keck School of Medicine at the University of Southern California, Los Angeles
| | - Alfredo A. Sadun
- Doheny Eye Institute and Keck School of Medicine at the University of Southern California, Los Angeles
| |
Collapse
|
9
|
Fatehi N, Nowroozizadeh S, Henry S, Coleman AL, Caprioli J, Nouri-Mahdavi K. Association of Structural and Functional Measures With Contrast Sensitivity in Glaucoma. Am J Ophthalmol 2017; 178:129-139. [PMID: 28342719 DOI: 10.1016/j.ajo.2017.03.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 03/15/2017] [Accepted: 03/15/2017] [Indexed: 11/25/2022]
Abstract
PURPOSE To test the hypothesis that structural and functional measures predict contrast sensitivity (CS) outcomes in glaucomatous eyes. DESIGN Cross-sectional prospective study. METHODS One hundred five eyes of 65 patients who underwent macular spectral-domain optical coherence tomography imaging, 24-2 standard achromatic visual fields (VF), and CS measurement on the same day were enrolled. Association of CS at 4 spatial frequencies (3, 6, 12, and 18 cycles per degree, cpd) with structural and functional outcomes was explored with correlation and regression analyses. RESULTS The median (IQR) 24-2 visual field mean deviation was -7.6 (-11.1 to -3.0). Significant correlations were found between CS at 6 cpd and ganglion cell/inner plexiform layer thickness at inferotemporal and inferonasal macular sectors (ρ = 0.222, P = .023 and ρ = 0.209, P = .032, respectively). CS at 6 cpd demonstrated higher correlations with full macular thickness measurements, the strongest of which was with the central macular thickness in the superior 6 × 3-degree region (ρ = 0.311, P = .001). Contrast sensitivity at 6 cpd also had the strongest correlation with mean deviation of the 4 central VF points (ρ = -0.420; P < .001). There was a significant correlation between logMAR visual acuity and contrast sensitivity at 6, 12, and 18 cpd (ρ = -0.306, ρ = -0.348 and ρ = -0.241, P < .013, respectively). CONCLUSIONS Structural and functional measures showed a fair relationship with contrast sensitivity. This association was most prominent between full-thickness macular measures or central VF parameters and CS at 6 cpd. Contrast sensitivity was not a reliable surrogate for glaucoma severity in this cross-sectional study.
Collapse
|
10
|
Evaluation of Contrast Sensitivity, Chromatic Vision, and Reading Ability in Patients with Primary Open Angle Glaucoma. J Ophthalmol 2016; 2016:7074016. [PMID: 27872754 PMCID: PMC5107829 DOI: 10.1155/2016/7074016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 10/11/2016] [Indexed: 11/17/2022] Open
Abstract
Purpose. To compare contrast sensitivity, acquired color vision deficiency, and reading ability in patients with glaucoma at different stages of the disease and to establish correlations between visual field parameters and visual function scores. Methods. This prospective cross-sectional study included 121 glaucoma patients. Subjects with a diagnosis of chronic open angle glaucoma were recruited and classified according to Hodapp-Parrish-Anderson criteria. Patients with severe visual field defects were excluded because they were older, which could bias the interpretation of visual function tests. Contrast sensitivity was measured using the Pelli-Robson Chart and the CSV1000E test. Chromatic vision was evaluated using the Farnsworth-panel D15 and the L'Anthony D15 tests of Vision Color Recorder software. Reading ability was measured using Radner-Vissum test. Results. Contrast sensitivity (with photopic and mesopic luminance with glare) differed significantly between patients with early and moderate visual field defects (p < 0.05). Reading ability scores and results of the chromatic vision tests did not differ significantly between the two groups. Significant and moderate Spearman correlations between visual field indexes and contrast sensitivity tests were detected. Conclusions. Contrast sensitivity was significantly worse in patients with moderate glaucoma compared to those with early-stage glaucoma. Evaluation of visual function in clinical practice provides important information to address a glaucoma patient's vision complaints.
Collapse
|
11
|
|
12
|
Richman J, Zangalli C, Lu L, Wizov SS, Spaeth E, Spaeth GL. The Spaeth/Richman contrast sensitivity test (SPARCS): design, reproducibility and ability to identify patients with glaucoma. Br J Ophthalmol 2014; 99:16-20. [PMID: 25053760 DOI: 10.1136/bjophthalmol-2014-305223] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS (1) To determine the ability of a novel, internet-based contrast sensitivity test titled the Spaeth/Richman Contrast Sensitivity Test (SPARCS) to identify patients with glaucoma. (2) To determine the test-retest reliability of SPARCS. METHODS A prospective, cross-sectional study of patients with glaucoma and controls was performed. Subjects were assessed by SPARCS and the Pelli-Robson chart. Reliability of each test was assessed by the intraclass correlation coefficient and the coefficient of repeatability. Sensitivity and specificity for identifying glaucoma was also evaluated. RESULTS The intraclass correlation coefficient for SPARCS was 0.97 and 0.98 for Pelli-Robson. The coefficient of repeatability for SPARCS was ±6.7% and ±6.4% for Pelli-Robson. SPARCS identified patients with glaucoma with 79% sensitivity and 93% specificity. CONCLUSIONS SPARCS has high test-retest reliability. It is easily accessible via the internet and identifies patients with glaucoma well. TRIAL REGISTRATION NCT01300949.
Collapse
Affiliation(s)
- Jesse Richman
- Glaucoma Service, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA
| | - Camila Zangalli
- Glaucoma Service, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA
| | - Lan Lu
- Glaucoma Service, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA
| | - Sheryl S Wizov
- Glaucoma Service, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA
| | - Eric Spaeth
- Glaucoma Service, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA
| | - George L Spaeth
- Glaucoma Service, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA
| |
Collapse
|
13
|
Chen G, Hou F, Yan FF, Zhang P, Xi J, Zhou Y, Lu ZL, Huang CB. Noise provides new insights on contrast sensitivity function. PLoS One 2014; 9:e90579. [PMID: 24626135 PMCID: PMC3953123 DOI: 10.1371/journal.pone.0090579] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 02/03/2014] [Indexed: 11/27/2022] Open
Abstract
Sensitivity to luminance difference, or contrast sensitivity, is critical for animals to survive in and interact with the external world. The contrast sensitivity function (CSF), which measures visual sensitivity to spatial patterns over a wide range of spatial frequencies, provides a comprehensive characterization of the visual system. Despite its popularity and significance in both basic research and clinical practice, it hasn’t been clear what determines the CSF and how the factors underlying the CSF change in different conditions. In the current study, we applied the external noise method and perceptual template model to a wide range of external noise and spatial frequency (SF) conditions, and evaluated how the various sources of observer inefficiency changed with SF and determined the limiting factors underlying the CSF. We found that only internal additive noise and template gain changed significantly with SF, while the transducer non-linearity and coefficient for multiplicative noise were constant. The 12-parameter model provided a very good account of all the data in the 200 tested conditions (86.5%, 86.2%, 89.5%, and 96.4% for the four subjects, respectively). Our results suggest a re-consideration of the popular spatial vision model that employs the CSF as the front-end filter and constant internal additive noise across spatial frequencies. The study will also be of interest to scientists and clinicians engaged in characterizing spatial vision deficits and/or developing rehabilitation methods to restore spatial vision in clinical populations.
Collapse
Affiliation(s)
- Ge Chen
- Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fang Hou
- Center for Cognitive and Brain Sciences, Department of Psychology, Ohio State University, Columbus, Ohio, United States of America
| | - Fang-Fang Yan
- Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Pan Zhang
- Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Jie Xi
- Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Yifeng Zhou
- Key Laboratory of Brain Function and Diseases, Chinese Academy of Sciences, and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Zhong-Lin Lu
- Center for Cognitive and Brain Sciences, Department of Psychology, Ohio State University, Columbus, Ohio, United States of America
| | - Chang-Bing Huang
- Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- * E-mail:
| |
Collapse
|
14
|
Casson RJ, Han G, Ebneter A, Chidlow G, Glihotra J, Newland H, Wood JPM. Glucose-induced temporary visual recovery in primary open-angle glaucoma: a double-blind, randomized study. Ophthalmology 2014; 121:1203-11. [PMID: 24491639 DOI: 10.1016/j.ophtha.2013.12.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 08/30/2013] [Accepted: 12/05/2013] [Indexed: 10/25/2022] Open
Abstract
PURPOSE To investigate the effect of topical glucose on visual parameters in individuals with primary open-angle glaucoma (POAG). DESIGN Double-blind, randomized, crossover study. PARTICIPANTS Nondiabetic pseudophakic patients with definite POAG were recruited; 29 eyes of 16 individuals participated in study 1. A follow-up study (study 2) included 14 eyes of 7 individuals. INTERVENTION Eyes were randomly allocated to receive 50% glucose or saline eye drops every 5 minutes for 60 minutes. MAIN OUTCOME MEASURES The contrast sensitivity and best-corrected logarithm of the minimum angle of resolution (logMAR). RESULTS The 50% glucose reached the vitreous in pseudophakic but not phakic individuals. Glucose significantly improved the mean contrast sensitivity at 12 cycles/degree compared with 0.9% saline by 0.26 log units (95% confidence interval [CI], 0.13-0.38; P < 0.001) and 0.40 log units (95% CI, 0.17-0.60; P < 0.001) in the follow-up study. The intraocular pressure, refraction, and central corneal thickness were not affected by glucose; age was not a significant predictor of the response. CONCLUSIONS Topical glucose temporarily improves psychophysical visual parameters in some individuals with POAG, suggesting that neuronal energy substrate delivery to the vitreous reservoir may recover function of "sick" retinal neurons.
Collapse
Affiliation(s)
- Robert J Casson
- South Australian Institute of Ophthalmology, University of Adelaide, Adelaide, South Australia.
| | - Guoge Han
- South Australian Institute of Ophthalmology, University of Adelaide, Adelaide, South Australia
| | - Andreas Ebneter
- South Australian Institute of Ophthalmology, University of Adelaide, Adelaide, South Australia
| | - Glyn Chidlow
- South Australian Institute of Ophthalmology, University of Adelaide, Adelaide, South Australia
| | - Jagjit Glihotra
- South Australian Institute of Ophthalmology, University of Adelaide, Adelaide, South Australia
| | - Henry Newland
- South Australian Institute of Ophthalmology, University of Adelaide, Adelaide, South Australia
| | - John P M Wood
- South Australian Institute of Ophthalmology, University of Adelaide, Adelaide, South Australia
| |
Collapse
|
15
|
Contrast sensitivity of thyroid associated ophthalmopathy patients without obvious optic neuropathy. ScientificWorldJournal 2014; 2013:943789. [PMID: 24453927 PMCID: PMC3886572 DOI: 10.1155/2013/943789] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Accepted: 10/09/2013] [Indexed: 11/18/2022] Open
Abstract
Purpose. To compare the contrast sensitivity levels of thyroid associated ophthalmopathy (TAO) patients without obvious optic neuropathy with those of healthy people. Methods. Forty eyes of 20 TAO patients without dysthyroid optic neuropathy and 40 eyes of 20 healthy subjects were evaluated in this prospective case-controlled study. The contrast sensitivity functions (CSFs) of all subjects were measured by the functional acuity contrast test (FACT) in five frequencies which were 1,5 cpd (A), 3 cpd (B), 6 cpd (C), 12 cpd (D), and 18 cpd (E). Results were compared for both groups, and a correlation of CSF with Hertel and clinical activity scores was assessed. Results. There was no statistically significant difference between TAO patients and control groups for age and sex. TAO patients had lower levels than the control group in all the frequencies of CSFs (P < 0.05) and the difference in contrast sensitivity functions between the groups seems to be more significant in higher frequencies (B, C, D, and E) (P < 0.001). Conclusions. TAO patients without DON can have contrast sensitivity loss and this would probably imply subtle optic nerve dysfunction in early disease phase.
Collapse
|
16
|
Michael R, Guevara O, de la Paz M, Alvarez de Toledo J, Barraquer RI. Neural contrast sensitivity calculated from measured total contrast sensitivity and modulation transfer function. Acta Ophthalmol 2011; 89:278-83. [PMID: 19909292 DOI: 10.1111/j.1755-3768.2009.01665.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE To test the feasibility of calculating neural contrast sensitivity function (neural CSF) from conventionally measured total contrast sensitivity function (total CSF) and measured modulation transfer function (MTF). Neural CSF considers the retina and the brain, whereas total CSF considers the optical eye media, the retina and the brain together. METHODS We studied three groups comprising nine eyes each: one group with normal ocular optics but retinal alterations (mild diabetic retinopathy), one with altered ocular optics and normal retina (keratoconus), and a normal control group. RESULTS Total CSF in the keratoconus and retinopathy groups was significantly lower compared to the control group. Modulation transfer function for keratoconus was lower, and in the retinopathy group was similar to that of the control group. Calculated neural CSF in the diabetes mellitus group was lower than in the control group whereas in the keratoconus group it was similar to that of the control group, with overestimations for some keratoconus cases. CONCLUSION It is possible to calculate a meaningful neural CSF from measured total CSF and MTF data. The neural CSF represents a CSF adjusted for optical aberrations. This would allow comparison of the neural component of visual function in eyes with different optical aberrations.
Collapse
Affiliation(s)
- Ralph Michael
- Institut Universitari Barraquer, Universitat Autònoma de Barcelona, Spain.
| | | | | | | | | |
Collapse
|
17
|
González de la Rosa M, González-Hernández M, García-Feijoo J, Sánchez Méndez M, García-Sánchez J. [Comparing the ranges of defect measured with standard white on white and Pulsar perimetries]. ARCHIVOS DE LA SOCIEDAD ESPANOLA DE OFTALMOLOGIA 2011; 86:113-117. [PMID: 21569920 DOI: 10.1016/j.oftal.2010.11.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2008] [Accepted: 11/26/2010] [Indexed: 05/30/2023]
Abstract
OBJECTIVES Normal thresholds on Pulsar perimetry fall faster than those of standard perimetry in the peripheral visual field. Two related studies were performed. Firstly, the frequency distributions of glaucoma defects on standard automated perimetry (SAP) and the relationship of the centre and periphery (Study A) were studied first, followed by an attempt to establish the limits of pulsar perimetry (Study B). MATERIAL AND METHOD A: frequency of defects was calculated in 78.663 SAP perimetries (G1-TOP, Octopus 1-2-3, Haag-Streit). Study B: 204 eyes with mean defect (MD-SAP) lower than 9 dB were examined 8.92 ± 4.19 times with SAP (TOP-32, Octopus 311) and temporal modulation perimetry (T30W, Pulsar Perimeter, Haag-Streit). RESULTS Study A: 50.7% of the SAP examinations showed MD values lower than 9 dB and 32.7% bellow 6 dB. The MD correlation of the central 20° with the MD of the most peripheral points was r=0.933. Study B: in cases with MD-TOP-32 lower than 6 dB, SAP had the maximum possibility of detecting defect in 0.02% of points and Pulsar in 0.29%. In subjects with MD-TOP-32 between 6 and 9 dB frequencies were 0.38% in SAP and 3.5% in Pulsar (5.1% for eccentricities higher than 20°). CONCLUSIONS Pulsar allows detecting defects, without range limitations, in the initial half of SAP frequencies expected on glaucoma patients. In order to study the progression of deeper defects the examination should focus on the central points, where the dynamic range of both systems is more equivalent.
Collapse
Affiliation(s)
- M González de la Rosa
- Servicio de Oftalmología, Hospital Universitario de Canarias, Universidad de La Laguna, Islas Canarias, España.
| | | | | | | | | |
Collapse
|
18
|
Onal S, Yenice O, Cakir S, Temel A. FACT contrast sensitivity as a diagnostic tool in glaucoma: FACT contrast sensitivity in glaucoma. Int Ophthalmol 2007; 28:407-12. [PMID: 18000646 DOI: 10.1007/s10792-007-9169-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2007] [Accepted: 10/24/2007] [Indexed: 12/01/2022]
Abstract
PURPOSE To investigate spatial-contrast sensitivity (CS) assessment as a tool for diagnosis of early glaucoma in patients with good visual acuity. METHODS In this prospective cross-sectional study we evaluated one eye of 50 patients with primary open angle or normotensive glaucoma who were newly diagnosed. All met the 0.6, or better, vision requirement. CS was measured at 1.5, 3, 6, 12, and 18 cycles per degree (cpd) spatial frequencies for one luminance level (85 cd/m2) using the functional acuity contrast test (FACT). Visual fields were evaluated using the Humphrey 750i field analyzer and the 30-2 standard full threshold program. The results from the visual acuity and CS assessments were compared with results for 20 age-matched control subjects. RESULTS CS scores were significantly lower at all spatial frequencies for the glaucoma patients than for the control subjects. The sensitivity of CS measurements was generally around 50%. Specificity ranged between 68 and 100%. FACT CS scores of less than 22 at 12 cpd spatial frequency provided sensitivity and specificity values concomitantly exceeding 60%. CONCLUSIONS Both the presence of a significant difference between the CS of glaucoma patients and control subjects and a high specificity of contrast sensitivity suggests that the FACT test may be used as a tool for diagnosis of patients with glaucoma, besides other methods such as short-wavelength automated perimetry (SWAP).
Collapse
Affiliation(s)
- Sumru Onal
- Department of Ophthalmology, Marmara University, School of Medicine, Altunizade Mah., Okulcikmazi Sok. No: 11/5, Usküdar, 34660, Istanbul, Turkey.
| | | | | | | |
Collapse
|
19
|
Gonzalez-Hernandez M, Gonzalez de la Rosa M, Rodriguez de la Vega R, Hernandez-Vidal A. Long-Term Fluctuation of Standard Automatic Perimetry, Pulsar Perimetry and Frequency-Doubling Technology in Early Glaucoma Diagnosis. Ophthalmic Res 2007; 39:338-43. [DOI: 10.1159/000109997] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2006] [Accepted: 06/18/2007] [Indexed: 11/19/2022]
|
20
|
Nazemi PP, Fink W, Sadun AA, Francis B, Minckler D. Early detection of glaucoma by means of a novel 3D computer-automated visual field test. Br J Ophthalmol 2007; 91:1331-6. [PMID: 17504855 PMCID: PMC2001017 DOI: 10.1136/bjo.2007.116103] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2007] [Indexed: 11/04/2022]
Abstract
PURPOSE A recently devised 3D computer-automated threshold Amsler grid test was used to identify early and distinctive defects in people with suspected glaucoma. Further, the location, shape and depth of these field defects were characterised. Finally, the visual fields were compared with those obtained by standard automated perimetry. PATIENTS AND METHODS Glaucoma suspects were defined as those having elevated intraocular pressure (>21 mm Hg) or cup-to-disc ratio of >0.5. 33 patients and 66 eyes with risk factors for glaucoma were examined. 15 patients and 23 eyes with no risk factors were tested as controls. The recently developed 3D computer-automated threshold Amsler grid test was used. The test exhibits a grid on a computer screen at a preselected greyscale and angular resolution, and allows patients to trace those areas on the grid that are missing in their visual field using a touch screen. The 5-minute test required that the patients repeatedly outline scotomas on a touch screen with varied displays of contrast while maintaining their gaze on a central fixation marker. A 3D depiction of the visual field defects was then obtained that was further characterised by the location, shape and depth of the scotomas. The exam was repeated three times per eye. The results were compared to Humphrey visual field tests (ie, achromatic standard or SITA standard 30-2 or 24-2). RESULTS In this pilot study 79% of the eyes tested in the glaucoma-suspect group repeatedly demonstrated visual field loss with the 3D perimetry. The 3D depictions of visual field loss associated with these risk factors were all characteristic of or compatible with glaucoma. 71% of the eyes demonstrated arcuate defects or a nasal step. Constricted visual fields were shown in 29% of the eyes. No visual field changes were detected in the control group. CONCLUSIONS The 3D computer-automated threshold Amsler grid test may demonstrate visual field abnormalities characteristic of glaucoma in glaucoma suspects with normal achromatic Humphrey visual field testing. This test may be used as a screening tool for the early detection of glaucoma.
Collapse
Affiliation(s)
- Paul P Nazemi
- Doheny Eye Institute and Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA
| | | | | | | | | |
Collapse
|
21
|
Evans DW, Hosking SL, Gherghel D, Bartlett JD. Contrast sensitivity improves after brimonidine therapy in primary open angle glaucoma: a case for neuroprotection. Br J Ophthalmol 2004; 87:1463-5. [PMID: 14660453 PMCID: PMC1920576 DOI: 10.1136/bjo.87.12.1463] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS To determine the visual outcome following initiation of brimonidine therapy in glaucoma. METHODS 16 newly diagnosed previously untreated glaucoma patients were randomly assigned to either timolol 0.5% or brimonidine 0.2%. Visual acuity, contrast sensitivity (CS), visual fields, intraocular pressure (IOP), blood pressure, and heart rate were evaluated at baseline and after 3 months. RESULTS IOP reduction was similar for both groups (p<0.05). Brimonidine improved CS; in the right eye at 6 and 12 cpd (p=0.043, p=0.017); in the left eye at 3 and 12 cpd (p=0.044, p=0.046). Timolol reduced CS at 18 cpd in the right eye (p=0.041). There was no change in any other measured parameters. CONCLUSION Glaucoma patients exhibit improved CS on initiation of brimonidine therapy.
Collapse
Affiliation(s)
- D W Evans
- School of Optometry, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | | |
Collapse
|
22
|
Comparison of Contrast Sensitivity, Visual Acuity, and Humphrey Visual Field Testing in Patients with Glaucoma. J Glaucoma 2003. [DOI: 10.1097/00061198-200304000-00008] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
23
|
Nelson P, Aspinall P, Papasouliotis O, Worton B, O'Brien C. Quality of life in glaucoma and its relationship with visual function. J Glaucoma 2003; 12:139-50. [PMID: 12671469 DOI: 10.1097/00061198-200304000-00009] [Citation(s) in RCA: 253] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE The aims of this study were (a) to explore patients self-reported visual disability resulting from glaucoma by means of a questionnaire developed for this purpose; (b) identify activities strongly associated with a measure of visual field loss, (c) to quantify different psychophysical aspects of visual function; (d) to assess the relationship between objective measures of visual function and patients' perception of their vision-related quality of life. PATIENTS AND METHODS Three groups of glaucoma patients (n = 47) with mild (n = 18), moderate (n = 19), and severe visual field loss (n = 10) and a group of normal controls (n = 19) underwent a comprehensive clinical examination, completed a questionnaire and, on a separate visit, performed a number of psychophysical tests of visual function. MAIN OUTCOME MEASURES Questionnaire responses (vision-related quality of life, general health and psychosocial variables), visual acuity, visual fields, Esterman binocular disability scores, contrast sensitivity, critical flicker frequency, color vision, dark adaptation, glare disability (brightness acuity), and stereoacuity scores were measured. RESULTS Fifteen of the 50 questions were noted to have a strong significant relationship with a measure of visual field loss and were included in a new questionnaire scale, the Glaucoma Quality of Life - 15 (GQL-15). The scale validity showed a significant correlation with perimetric mean deviation (MD) values (r = -0.6; P < 0.0001), the reliability of the scale was high (Cronbach alpha = 0.95), and test-retest reliability of the questionnaire was strong (r = 0.87). An overall statistically significant decrease in performance-related quality of life was noted between normal subjects and all groups of glaucoma patients. A significant relationship was found between the scale questionnaire summary performance measure and a number of psychophysical tests: Pelli-Robson contrast sensitivity (r = -0.45, P < 0.001), glare disability (r = -0.41, P < 0.001), Esterman binocular visual field test (r = -0.39, P < 0.001), dark adaptation (r = 0.34, P = 0.007), and stereopsis (r = 0.26, P = 0.04). CONCLUSION Perceived visual disability relating to certain tasks (particularly involving dark adaptation and disability glare, activities demanding functional peripheral vision such us tripping over and bumping into objects and outdoor mobility tasks) was significantly associated with the severity of binocular visual field loss. As a result, a new glaucoma-specific questionnaire scale with good performance characteristics is presented in this study. The difficulties encountered by patients in everyday life (as measured with the questionnaire) were also mirrored in their performance on a number of psychophysical tests, especially contrast sensitivity, glare disability, Esterman binocular visual field test, and dark adaptation.
Collapse
Affiliation(s)
- Patricia Nelson
- Department of Ophthalmology, Princess Alexandra Eye Pavilion, Edinburgh, Scotland, United Kingdom.
| | | | | | | | | |
Collapse
|
24
|
Anderson RS, Coulter E, Zlatkova MB, Demirel S. Short-wavelength acuity: optical factors affecting detection and resolution of blue-yellow sinusoidal gratings in foveal and peripheral vision. Vision Res 2003; 43:101-7. [PMID: 12505609 DOI: 10.1016/s0042-6989(02)00410-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Previous studies have indicated that peripheral achromatic grating resolution is limited by the sampling density of the neural array (sampling limited), and largely unaffected by large amounts of optical defocus and significant changes in luminance. Under certain conditions, peripheral short-wavelength sensitive (SWS) grating acuity is also sampling limited. We wished to determine how the sampling-limited nature of SWS-driven grating resolution was affected by changing optical defocus and stimulus luminance. Using SWS-cone isolation techniques, detection and resolution acuity were measured for sinusoidal gratings under varying levels of stimulus mean luminance and optical defocus in the fovea and at 20 degrees eccentricity. From 1.4 down to 0.3 cd/m(2) peripheral detection acuity was superior to resolution acuity, accompanied by observations of aliasing: there was little change in resolution performance throughout this range. For defocus up to 3-4 dioptres, peripheral detection acuity was superior to resolution but fell steadily: resolution performance remained flat throughout the same range. Unlike achromatic acuity, foveal resolution performance displayed some robustness to defocus but to a lesser degree than the periphery. Peripheral SWS-driven resolution remains sampling limited for large changes in stimulus luminance and optical defocus, and should thus be useful as a clinical test of SWS-driven ganglion cell density.
Collapse
Affiliation(s)
- Roger S Anderson
- Vision Science Research Group, School of Biomedical Sciences, University of Ulster at Coleraine, Co Londonderry BT52 1SA, UK.
| | | | | | | |
Collapse
|
25
|
Anderson RS, Zlatkova MB, Demirel S. What limits detection and resolution of short-wavelength sinusoidal gratings across the retina? Vision Res 2002; 42:981-90. [PMID: 11934450 DOI: 10.1016/s0042-6989(02)00013-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Peripheral resolution acuity for achromatic gratings is known to be limited by the density of the underlying ganglion cell sampling array. After confirming isolation of the short-wavelength sensitive (SWS) system using chromatic adaptation methods, we wished to determine if resolution is limited by blue/yellow ganglion cell sampling (evidenced by a superiority of detection over resolution acuity and the perception of aliasing) and thus directly related to SWS-driven ganglion cell density. We measured detection and resolution acuity between 0 degrees and 35 degrees, using blue sinusoidal gratings superimposed on a yellow adapting background which ranged in intensity from 2.5 to 4.7logTrolands. At all locations, a break could be observed in the acuity vs. illumination curves followed by a plateau. Detection and resolution acuity were the same for low background intensities, but resolution acuity was lower than detection at higher intensities, accompanied by observations of chromatic aliasing. SWS resolution is sampling-limited across the retina and agrees well with predicted performance based on anatomical estimates of small bistratified ganglion cell density.
Collapse
Affiliation(s)
- Roger S Anderson
- Vision Science Research Group, School of Biomedical Sciences, University of Ulster at Coleraine, Co. Londonderry, BT52 1SA, Northern Ireland, UK.
| | | | | |
Collapse
|
26
|
Ivers RQ, Optom B, Macaskill P, Cumming RG, Mitchell P. Sensitivity and specificity of tests to detect eye disease in an older population. Ophthalmology 2001; 108:968-75. [PMID: 11320029 DOI: 10.1016/s0161-6420(00)00649-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To compare the ability of tests of visual function to detect the presence of eye disease. DESIGN Cross-sectional study. PARTICIPANTS Three thousand six hundred fifty-four of 4433 (82.4%) eligible residents of an area near Sydney aged 49 years and older had a detailed eye examination, including retinal and lens photography and subsequent grading of eye disease, tests of presenting and corrected visual acuity, contrast sensitivity, screening visual field and intraocular pressure. MAIN OUTCOME MEASURES Receiver operator characteristic (ROC) curves were created and area under the curve compared for each vision test. Sensitivity and specificity were calculated for each test. RESULTS No single vision test predicted the presence of eye disease with any consistency. Best-corrected visual acuity or contrast sensitivity had the highest area under the ROC curve for most eye diseases examined but had poor sensitivity and specificity. For glaucoma and diabetic retinopathy there was no difference in area under the curve for any of the tests examined, and no test had a good balance of sensitivity and specificity. Screening tests (performed with presenting correction) did not perform as well as nonscreening tests (those carried out after refraction with best correction). CONCLUSIONS Current vision tests are not particularly good at detecting eye disease compared with the "gold standard" of a full eye examination performed by an ophthalmologist. Further work in this area should be carried out before vision screening programs can be recommended for implementation among older people.
Collapse
Affiliation(s)
- R Q Ivers
- Institute for International Health, University of Sydney, Sydney, Australia
| | | | | | | | | |
Collapse
|
27
|
Sponsel WE, Arango S, Trigo Y, Mensah J. Clinical classification of glaucomatous visual field loss by frequency doubling perimetry. Am J Ophthalmol 1998; 125:830-6. [PMID: 9645720 DOI: 10.1016/s0002-9394(98)00047-6] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To determine whether the frequency doubling perimeter (FDP) can grade glaucomatous visual function loss in a clinically relevant manner. Sinusoidal gratings < 1 cpd that undergo counterphase flicker > 15 Hz appear to have twice as many bands of light, a phenomenon referred to as the "frequency doubling illusion." Evidence suggests that this psychophysical effect is mediated in part by large-diameter ganglion cells, which are reported to be lost early in the glaucomatous disease process. A portable, commercially available FDP has already demonstrated high diagnostic potential for glaucoma screening. METHODS Sixty-four eyes of 42 glaucomatous patients and 22 eyes of 14 normal subjects were evaluated by means of both frequency doubling perimetry and Humphrey perimetry. A clinical scoring algorithm modeled after the Hodapp-Parrish-Anderson criteria for scoring Humphrey visual field defects was derived for the FDP at the halfway point of the study, and all participants were reassessed with this algorithm upon its completion. RESULTS FDP mean and pattern deviation showed strong linear correlations with Humphrey 30-2 mean deviation (R = 0.75; P < .0001) and corrected pattern standard deviation values (R = 0.64; P < .0001). Despite this, neither global index could consistently categorize the graded glaucomatous visual fields in a manner consistent with the Hodapp-Parrish-Anderson criteria. The new FDP scoring algorithm did provide good segregation (73% precise parity, 93% parity within one Humphrey grade). CONCLUSIONS Sixteen-zone frequency doubling perimetry can segregate glaucomatous visual field loss into pathologic categories approximating those obtained with Humphrey 30-2 perimetry by means of a formula modeled after the Hodapp-Parrish-Anderson criteria.
Collapse
Affiliation(s)
- W E Sponsel
- South Texas Ocular Imaging Center, University of Texas Health Science Center, San Antonio, USA.
| | | | | | | |
Collapse
|
28
|
Abstract
Glaucoma reportedly affects motion perception. As an initial step in characterizing glaucoma-induced changes in the motion system, we determined the range of temporal frequencies that the motion system could process. A noise-masking paradigm was used to measure contrast energy thresholds of 26 glaucoma patients at various stages of the disease and 16 age-similar subjects with normal vision. Using a sinusoidal stimulus, thresholds were measured for the discrimination of motion direction and for the stimulus embedded within a pattern of dynamic spatial noise. The noise was filtered to contain only low spatial frequencies, and the temporal-frequency spectrum of the noise was manipulated across conditions to derive the temporal filter shape of the most efficient motion sensor. The results show that the range of temporal frequencies processed by the motion system is diminished in the glaucoma group. The filters of the glaucoma subjects have reduced bandwidths compared with the normal-vision group. In addition, the upper cut-off frequency of the filters of the glaucoma subjects is correlated with stage of disease as indexed by the mean deviation of the Humphrey Visual Field Analyzer program 24-2, as well as the cup-to-disk ratio.
Collapse
Affiliation(s)
- K A Turano
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
| | | | | |
Collapse
|
29
|
Abstract
A new contrast sensitivity (CS) card test was used to estimate contrast sensitivity in 18 infants and children with Down syndrome (DS). The results showed that although the overall shape of the contrast sensitivity functions (CSFs) of the subjects with DS was the typical inverted-U, their CSFs were depressed in comparison to control subjects and this relative loss became larger with increasing spatial frequency. In addition, there was little improvement in CS with age and the mean CSF among children with DS (mean age = 7.3 years) was equivalent statistically to a group of 12-month-olds without DS. The Teller Acuity Cards (TAC) were also used to assess visual acuity in 17 of the 18 children in our sample. The results of these tests showed that their visual acuity (VA) was significantly lower than normal, but was consistent with that extrapolated from each subject's CSF. Taken together with previous anatomical and developmental findings, our results suggest that the deficits in spatial vision among children with DS is due primarily to restricted cortical development, and secondarily, to the additional accommodative and ocular conditions that are prevalent in this population.
Collapse
Affiliation(s)
- M L Courage
- Department of Psychology, Memorial University of Newfoundland St. John's, Canada.
| | | | | |
Collapse
|
30
|
Bose S, Piltz JR, Breton ME. Nimodipine, a centrally active calcium antagonist, exerts a beneficial effect on contrast sensitivity in patients with normal-tension glaucoma and in control subjects. Ophthalmology 1995; 102:1236-41. [PMID: 9097753 DOI: 10.1016/s0161-6420(95)30884-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND/PURPOSE The use of calcium antagonists in patients with normal-tension glaucoma (NTG) currently is under investigation. The aim of this study is to evaluate the effect of an acute dose of oral nimodipine, a centrally active calcium antagonist, on spatial contrast sensitivity in patients with NTG and in age-matched control subjects. METHODS Spatial contrast sensitivity was measured using the Pelli-Robson and the Vistech 6000 charts in 14 patients with NTG and in 17 control subjects. Testing was performed at baseline and at two subsequent sessions. Measurements were recorded 2 hours after oral administration of either nimodipine or placebo in a randomized, double-masked manner. Data were analyzed using unpaired, two-tailed Student's t test for between-group comparisons and repeated measures analysis of variance for within-group comparisons. RESULTS Using the Pelli-Robson charts, baseline contrast sensitivity was significantly lower in patients with NTG compared with control subjects (P < 0.05, unpaired Student's t test). There was a significant increase in log contrast sensitivity after administration of nimodipine compared with baseline and placebo in patients with NTG (baseline, 1.39 +/- 0.38; placebo, 1.41 +/- 0.40; nimodipine, 1.51 +/- 0.39) and in control subjects (baseline, 1.62 +/- 0.11; placebo, 1.64 +/- 0.10; nimodipine, 1.81 +/- 0.14) (P < 0.05, repeated measures analysis of variance). A similar trend was observed using the Vistech charts. CONCLUSION These results suggest that central visual function as measured by Pelli-Robson and Vistech contrast sensitivity is impaired in eyes with NTG. An acute, oral administration of nimodipine, a calcium antagonist, improved contrast sensitivity in patients with NTG and in control subjects. The mechanism of this improvement is not fully understood. Further studies are needed to evaluate the effect of long-term administration in glaucoma.
Collapse
Affiliation(s)
- S Bose
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia 19104, USA
| | | | | |
Collapse
|
31
|
Lundh BL, Gottvall E. Peripheral contrast sensitivity for dynamic sinusoidal gratings in early glaucoma. ACTA OPHTHALMOLOGICA SCANDINAVICA 1995; 73:202-6. [PMID: 7493229 DOI: 10.1111/j.1600-0420.1995.tb00269.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Automated contrast thresholds were established for dynamic, 2 reversals per sec phase-shifted, sinusoidal gratings in a 5 degrees circular test field centred 7.5 degrees from the fixation point in six positions in the visual field in 16 patients (age 56-76 years) with clinically established (optic disc or nerve fibre layer damage) early glaucoma, without visual field defects. For reference, contrast thresholds were also obtained in 16 sex-matched and age-matched controls. For all three spatial frequencies, thresholds were raised in the glaucoma group (0.5 c/deg: p = 0.0034-0.041, 2 positions n.s.; 1.0 c/deg: p = 0.0093-0.049, 1 position n.s.; 2.0 c/deg: p = 0.0011-0.041, 1 position n.s.). Deficiencies did not correlate to glaucoma type (simplex vs capsular), intraocular pressure level at examination, visual acuity, or local therapy (beta-blockers vs miotics). In the glaucoma group, there was a general loss of contrast sensitivity in all six positions tested in the visual field, reflected in roughly similar threshold elevations. Losses appeared slightly greater in the lower hemi-field. Definite contrast threshold elevations from the early glaucomatous process were established in this group of glaucoma patients without visual field defects. However, the method was considered to be of less value in glaucoma detection for individual subjects, due to the large overlap in threshold values between glaucoma patients and controls.
Collapse
Affiliation(s)
- B L Lundh
- Department of Ophthalmology, University Hospital, Linköping, Sweden
| | | |
Collapse
|
32
|
Pfoff DS, Werner JS. Effect of cataract surgery on contrast sensitivity and glare in patients with 20/50 or better Snellen acuity. J Cataract Refract Surg 1994; 20:620-5. [PMID: 7837072 DOI: 10.1016/s0886-3350(13)80650-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The effect of cataract surgery was assessed in 103 patients whose visual acuity, as measured in dim light and with high contrast Snellen letters, was 20/50 or better. The patients desired cataract surgery. They complained of glare symptoms, had given up driving at night, or both. Contrast sensitivity was measured under simulated night conditions with a calibrated Vistech MCT 8000 device. No patient who had a contrast sensitivity of less than 27 at 6 cycles per degree (20/70 "equivalent acuity") had cataract surgery. The mean preoperative contrast sensitivity function showed abnormally low values for all frequencies (cycles/degree) tested. Postoperatively the values returned to normal. Of 99 patients who answered a postoperative questionnaire, 41 (41%) had been driving at night preoperatively and 80 (80%) were driving at night postoperatively. A control group of 24 noncataractous patients (48 eyes) was in the normal range of the test device used. These results support the view that the benefits of cataract surgery are not well predicted by Snellen acuity, even though functional vision may be significantly reduced.
Collapse
|
33
|
Affiliation(s)
- J E Morgan
- Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, Connecticut 06520-8061
| |
Collapse
|
34
|
Suttorp-Schulten MS, Tijssen R, Mourits MP, Apkarian P. Contrast sensitivity function in Graves' ophthalmopathy and dysthyroid optic neuropathy. Br J Ophthalmol 1993; 77:709-12. [PMID: 8280684 PMCID: PMC504629 DOI: 10.1136/bjo.77.11.709] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Contrast sensitivity function was measured by a computer automated method on 38 eyes with dysthyroid optic neuropathy and 34 eyes with Graves' ophthalmopathy only. The results were compared with 74 healthy control eyes. Disturbances of contrast sensitivity functions were found in both groups when compared with controls. The eyes affected with dysthyroid optic neuropathy showed pronounced loss of contrast sensitivity in the low frequency range, which facilitates differentiation between the two groups.
Collapse
|