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1.
Ophthalmol Sci ; 4(2): 100422, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38187128

RESUMEN

Purpose: Eccentric viewing training for macular disease has been performed for > 40 years, but no large studies including control groups have assessed the benefits of this training. The EFFECT (Eccentric Fixation From Enhanced Clinical Training) study is a large randomized controlled trial of 2 types of eccentric viewing training. Design: Randomized controlled trial. Participants: Two hundred adults with age-related macular disease. Methods: Participants were randomized to either of the following: (1) a control group; (2) a group receiving supervised reading support; (3) a group receiving 3 sessions of training to optimize the use of their own preferred retinal locus; or (4) a group receiving 3 sessions of biofeedback training of a theoretically optimal trained retinal locus. All participants received standard low-vision rehabilitation. Main Outcome Measures: The primary outcome was patient-reported visual task ability measured on the Activity Inventory instrument at goal level. Secondary outcomes included reading performance and fixation stability. Results: There was no difference between groups on change in task ability (F(3,174) = 1.48, P = 0.22) or on any of the secondary outcome measures. Visual acuity and contrast sensitivity fell in all groups, suggesting that disease progression outweighed any benefit of training. Conclusions: Eccentric viewing training did not systematically improve task ability, reading performance, or fixation stability in this study. Our results do not support the routine use of eccentric viewing training for people with progressing age-related macular disease, although this training may help people with end-stage disease. Rehabilitation of an inherently progressive condition is challenging. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

2.
Transl Vis Sci Technol ; 12(7): 19, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37477933

RESUMEN

Purpose: The purpose of this study was to assess test-retest variability and discriminatory power of measures from macular integrity assessment (S-MAIA) and AdaptDx. Methods: This is a cross-sectional study of 167 people with intermediate age-related macular degeneration (iAMD), no AMD (controls; n = 54), early AMD (n = 28), and late AMD (n = 41), recruited across 18 European ophthalmology centers. Repeat measures of mesopic and scotopic S-MAIA average (mean) threshold (MMAT decibels [dB] and SMAT [dB]) and rod intercept time (RIT [mins]) at 2 visits 14 (±7) days apart were recorded. Repeat measures were assessed by Bland-Altman analysis, intra-class correlation coefficients (ICCs) and variability ratios. Secondary analysis assessed the area under the receiver operating characteristic curves (AUC) to determine the ability to distinguish people as having no AMD, early AMD, or iAMD. Results: Data were available for 128, 131, and 103 iAMD participants for the mesopic and scotopic S-MAIA and AdaptDx, respectively. MMAT and SMAT demonstrate similar test-retest variability in iAMD (95% confidence interval [CI] ICC of 0.79-0.89 and 0.78-0.89, respectively). ICCs were worse in RIT (95% CI ICC = 0.55-0.77). All tests had equivalent AUCs (approximately 70%) distinguishing between subjects with iAMD and controls, whereas early AMD was indistinguishable from iAMD on all measures (AUC = <55%). A learning effect was not seen in these assessments under the operating procedures used. Conclusions: MMAT, SMAT, and RIT have adequate test-retest variability and are all moderately good at separating people with iAMD from controls. Translational Relevance: Expected levels of test-retest variability and discriminatory power of the AdaptDx and MAIA devices in a clinical study setting must be considered when designing future trials for people with AMD.


Asunto(s)
Degeneración Macular , Pruebas del Campo Visual , Humanos , Adaptación a la Oscuridad , Estudios Transversales
3.
JAMA Ophthalmol ; 140(8): 780-789, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35737401

RESUMEN

Importance: There is a need for validated clinical end points that are reliably able to quantify potential therapeutic effects of future treatments targeting age-related macular degeneration (AMD) before the onset of serious visual impairment. Objective: To assess the reliability and discriminatory power of 5 simple chart-based visual function (VF) tests as potential measures for clinical trial end points with regulatory and patient-access intention in intermediate AMD (iAMD). Design, Setting, and Participants: This international noninterventional study took place at 18 tertiary ophthalmology departments across Europe. Participants were recruited between April 2018 and March 2020 and were identified during routine clinical review. Participants with no AMD and early AMD were recruited from hospital staff, friends, and family of participants with AMD and via referrals from community ophthalmologists and optometrists. The repeatability and discriminatory power of 5 simple chart-based assessments of VF (best-corrected visual acuity [BCVA], low-luminance visual acuity [LLVA], Moorfields Acuity Test [MAT], Pelli-Robson Contrast Sensitivity [CS], and International Reading Speed Test [IReST]) were assessed in a repeated-measures design. VF assessments were performed on day 0 and day 14. Participants with early AMD, iAMD, late AMD, and no AMD were recruited. Main Outcomes and Measures: Intraclass correlation coefficients (ICCs) and Bland-Altman 95% limits of agreement (LoA) were computed to assess repeatability. Area under the receiver operating characteristic curves (AUCs) determined the discriminatory ability of all measures to classify individuals as having no AMD or iAMD and to differentiate iAMD from its neighboring disease states. Results: A total of 301 participants (mean [SD] age, 71 [7] years; 187 female participants [62.1%]) were included in the study. Thirty-four participants (11.3%) had early AMD, 168 (55.8%) had iAMD, 43 (14.3%) had late AMD, and 56 (18.6%) had no AMD. ICCs for all VF measures ranged between 0.88 and 0.96 when all participants were considered, indicating good to excellent repeatability. All measures displayed excellent discrimination between iAMD and late AMD (AUC, 0.92-0.99). Early AMD was indistinguishable from iAMD on all measures (AUC, 0.54-0.64). CS afforded the best discrimination between no AMD and iAMD (AUC, 0.77). Under the same conditions, BCVA, LLVA, and MAT were fair discriminators (AUC, 0.69-0.71), and IReST had poor discrimination (AUC, 0.57-0.61). Conclusions and Relevance: BCVA, LLVA, MAT, CS, and IReST had adequate repeatability in this multicenter, multiexaminer setting but limited power to discriminate between no AMD and iAMD. The prognostic power of these variables to predict conversion from iAMD to late AMD is being examined in the ongoing longitudinal part of the MACUSTAR study.


Asunto(s)
Degeneración Macular , Anciano , Sensibilidad de Contraste , Femenino , Humanos , Degeneración Macular/diagnóstico , Reproducibilidad de los Resultados , Trastornos de la Visión/diagnóstico , Pruebas de Visión , Agudeza Visual
4.
Transl Vis Sci Technol ; 9(8): 25, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32864194

RESUMEN

Translational research in vision prosthetics, gene therapy, optogenetics, stem cell and other forms of transplantation, and sensory substitution is creating new therapeutic options for patients with neural forms of blindness. The technical challenges faced by each of these disciplines differ considerably, but they all face the same challenge of how to assess vision in patients with ultra-low vision (ULV), who will be the earliest subjects to receive new therapies. Historically, there were few tests to assess vision in ULV patients. In the 1990s, the field of visual prosthetics expanded rapidly, and this activity led to a heightened need to develop better tests to quantify end points for clinical studies. Each group tended to develop novel tests, which made it difficult to compare outcomes across groups. The common lack of validation of the tests and the variable use of controls added to the challenge of interpreting the outcomes of these clinical studies. In 2014, at the bi-annual International "Eye and the Chip" meeting of experts in the field of visual prosthetics, a group of interested leaders agreed to work cooperatively to develop the International Harmonization of Outcomes and Vision Endpoints in Vision Restoration Trials (HOVER) Taskforce. Under this banner, more than 80 specialists across seven topic areas joined an effort to formulate guidelines for performing and reporting psychophysical tests in humans who participate in clinical trials for visual restoration. This document provides the complete version of the consensus opinions from the HOVER taskforce, which, together with its rules of governance, will be posted on the website of the Henry Ford Department of Ophthalmology (www.artificialvision.org). Research groups or companies that choose to follow these guidelines are encouraged to include a specific statement to that effect in their communications to the public. The Executive Committee of the HOVER Taskforce will maintain a list of all human psychophysical research in the relevant fields of research on the same website to provide an overview of methods and outcomes of all clinical work being performed in an attempt to restore vision to the blind. This website will also specify which scientific publications contain the statement of certification. The website will be updated every 2 years and continue to exist as a living document of worldwide efforts to restore vision to the blind. The HOVER consensus document has been written by over 80 of the world's experts in vision restoration and low vision and provides recommendations on the measurement and reporting of patient outcomes in vision restoration trials.


Asunto(s)
Visión Ocular , Prótesis Visuales , Ceguera , Consenso , Humanos , Trastornos de la Visión/terapia
5.
Transl Vis Sci Technol ; 9(10): 5, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32953245

RESUMEN

Purpose: To validate a vision-guided mobility assessment for individuals affected by RPE65-associated retinal dystrophy (RPE65-RD). Methods: In this comparative cross-sectional study, 29 subjects, comprising 19 subjects with RPE65-RD and 10 normally-sighted subjects undertook three assessments of mobility: following a straight line, navigating a simple maze, and stepping over a sidewalk "kerb." Performance was quantified as the time taken to complete each assessment, number of errors made, walking speed, and percent preferred walking speed, for each assessment. Subjects also undertook assessments of visual acuity, contrast sensitivity, full-field static perimetry, and age-appropriate quality of life questionnaires. To identify the most relevant metric to quantify vision-guided mobility, we investigated repeatability, as well as convergent, discriminant, and criterion validity. We also measured the effect of illumination on mobility. Results: Walking speed through the maze assessment best discriminated between RPE65-RD and normally-sighted subjects, with both convergent and discriminant validity. Walking speed also approached statistical significance when assessed for criterion validity (P = 0.052). Subjects with RPE65-RD had quantifiably poorer mobility at lower illumination levels. A relatively small mean difference (-0.09 m/s) was identified in comparison to a relatively large repeatability coefficient (1.10 m/s). Conclusions: We describe a novel, quantifiable, repeatable, and valid assessment of mobility designed specifically for subjects with RPE65-RD. The assessment is sensitive to the visual impairment of individuals with RPE65-RD in low illumination, identifies the known phenotypic heterogeneity and will furthermore provide an important outcome measure for RPE65-RD. Translational Relevance: This assessment of vision-guided mobility, validated in a dedicated cohort of subjects with RPE65-RD, is a relevant and quantifiable outcome measure for RPE65-RD.


Asunto(s)
Calidad de Vida , Distrofias Retinianas , Estudios Transversales , Humanos , Distrofias Retinianas/diagnóstico , Caminata , cis-trans-Isomerasas
6.
Trials ; 21(1): 659, 2020 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-32682441

RESUMEN

BACKGROUND: There is an unmet need for treatment options in intermediate age-related macular degeneration (iAMD). However, for any new interventions to be tested in clinical trials, novel currently unavailable clinical endpoints need to be developed. Thus, the MACUSTAR study aims to develop and evaluate functional, structural, and patient-reported candidate endpoints for use in future iAMD trials. METHODS: The protocol describes a low-interventional clinical multicenter study employing a novel two-part design. The cross-sectional part (total duration, 1 month) and the longitudinal part (total duration, 36 months) include participants with iAMD and control groups with early/late/no AMD. The cross-sectional part's primary objective is a technical evaluation of functional, structural, and patient-reported candidate outcomes. The longitudinal part's primary objective is to assess the prognostic power of changes in functional, structural, and patient-reported outcomes for progression from iAMD to late AMD. All data will be used to support a biomarker qualification procedure by regulatory authorities. DISCUSSION: The MACUSTAR study characterizes and evaluates much needed novel functional, structural, and patient-reported endpoints for future clinical trials in iAMD and will improve our understanding of the natural history and prognostic markers of this condition. TRIAL REGISTRATION: ClinicalTrials.gov NCT03349801 . Registered on 22 November 2017.


Asunto(s)
Determinación de Punto Final , Degeneración Macular , Proyectos de Investigación , Ensayos Clínicos como Asunto , Estudios Transversales , Humanos , Estudios Longitudinales , Degeneración Macular/diagnóstico , Degeneración Macular/terapia , Estudios Multicéntricos como Asunto , Estudios Observacionales como Asunto , Tomografía de Coherencia Óptica
7.
Ophthalmol Ther ; 9(3): 563-576, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32557168

RESUMEN

AIMS: To report the mean change in Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA) and reading performance (reading acuity and maximum reading speed (MRS) using the MNREAD test) between baseline and 24 months in treatment-naïve patients with neovascular age-related macular degeneration (nAMD) treated with intravitreal aflibercept injections. METHODS: A prospective, open-label, interventional non-randomised case series with 24 months' duration. Patients were recruited to the study from medical retina clinics at Moorfields Eye Hospital. Intravitreal injections of 2.0 mg aflibercept in the study eye were administered using a fixed dosing regimen during the first year and a treat-and-extend treatment regimen during the second year of treatment. RESULTS: Fifty patients were enrolled with a mean age (SD) of 78.7 (7.6) years; a mean BCVA of 62.8 ETDRS letters; mean reading acuity of 0.52 logMAR; mean maximum reading speed (MRS) of 141.3 words per minute and a central macular thickness of 322.6 µm at baseline. The mean improvement in BCVA was 6.4 letters for the 44 patients (88%) for whom data was available at 2 years. The mean improvement in reading acuity was 0.13 logMAR with an improvement in MRS of 2.9 words per minute. The mean reduction in CRT from baseline was 104.8 µm. CONCLUSIONS: Aflibercept treatment of nAMD using fixed dosing in year 1 and treat and extend in year 2 leads to improvements in reading ability, visual acuity and retinal morphology which were maintained to 2 years of treatment. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT02441816, the VITAL study.

8.
Ophthalmology ; 127(8): 1012-1019, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32386810

RESUMEN

PURPOSE: To report the 3-month results of a randomized trial (Femtosecond Laser-Assisted Cataract Trial [FACT]) comparing femtosecond laser-assisted cataract surgery (FLACS) with standard phacoemulsification cataract surgery (PCS). DESIGN: Multicenter, randomized controlled trial funded by the UK National Institute of Health Research (HTA 13/04/46/). PARTICIPANTS: Seven hundred eighty-five patients with age-related cataract. METHODS: This trial took place in 3 hospitals in the UK National Health Service (NHS). Randomization (1:1) was stratified by site, surgeon, and 1 or both eyes eligible using a secure web-based system. Postoperative assessments were masked to the allocated intervention. The primary outcome was unaided distance visual acuity (UDVA) in the study eye at 3 months. Secondary outcomes included corrected distance visual acuity, complications, and patient-reported outcomes measures. The noninferiority margin was 0.1 logarithm of the minimum angle of resolution (logMAR). ISRCTN.com registry, number ISRCTN77602616. MAIN OUTCOME MEASURES: We enrolled 785 participants between May 2015 and September 2017 and randomly assigned 392 to FLACS and 393 to PCS. At 3 months postoperatively, mean UDVA difference between treatment arms was -0.01 logMAR (-0.05 to 0.03), and mean corrected distance visual acuity difference was -0.01 logMAR (95% confidence interval [CI], -0.05 to 0.02). Seventy-one percent of both FLACS and PCS cases were within ±0.5 diopters (D) of the refractive target, and 93% of FLACS and 92% of PCS cases were within ±1.0 D. There were 2 posterior capsule tears in the PCS arm and none in the FLACS arm. There were no significant differences between arms for any secondary outcome. CONCLUSIONS: Femtosecond laser-assisted cataract surgery is not inferior to conventional PCS surgery 3 months after surgery. Both methods are as good in terms of vision, patient-reported health, and safety outcomes at 3 months. Longer-term outcomes of the clinical effectiveness and cost-effectiveness are awaited.


Asunto(s)
Terapia por Láser/métodos , Facoemulsificación/métodos , Agudeza Visual , Anciano , Análisis Costo-Beneficio , Femenino , Estudios de Seguimiento , Humanos , Masculino , Facoemulsificación/economía , Estudios Retrospectivos , Resultado del Tratamiento
9.
Ophthalmologica ; 241(2): 61-72, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30153664

RESUMEN

PURPOSE: Currently, no outcome measures are clinically validated and accepted as clinical endpoints by regulatory agencies for drug development in intermediate age-related macular degeneration (iAMD). The MACUSTAR Consortium, a public-private research group funded by the European Innovative Medicines Initiative intends to close this gap. PROCEDURES: Development of study protocol and statistical analysis plan including predictive modelling of multimodal endpoints based on a review of the literature and expert consensus. RESULTS: This observational study consists of a cross-sectional and a longitudinal part. Functional outcome measures assessed under low contrast and low luminance have the potential to detect progression of visual deficit within iAMD and to late AMD. Structural outcome measures will be multimodal and investigate topographical relationships with function. Current patient-reported outcome measures (PROMs) are not acceptable to regulators and may not capture the functional deficit specific to iAMD with needed precision, justifying development of novel PROMs for iAMD. The total sample size will be n = 750, consisting mainly of subjects with iAMD (n = 600). CONCLUSIONS: As clinical endpoints currently accepted by regulators cannot detect functional loss or patient-relevant impact in iAMD, we will clinically validate novel candidate endpoints for iAMD.


Asunto(s)
Manejo de la Enfermedad , Angiografía con Fluoresceína/métodos , Degeneración Macular/diagnóstico , Medición de Resultados Informados por el Paciente , Retina/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Fondo de Ojo , Humanos , Degeneración Macular/fisiopatología , Retina/fisiopatología
10.
J AAPOS ; 23(2): 115-117, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30502422

RESUMEN

Assessing the visual capabilities that remain to children affected with bilateral retinoblastoma has relied on psychophysical tests based on recognition visual acuity. We report a case in which fundus-driven perimetry and swept-source optical coherence tomography was performed in a patient with a macular tumor in the remaining eye as a novel way of further assessing fixation after oncological disease and treatment.


Asunto(s)
Mácula Lútea/diagnóstico por imagen , Neoplasias de la Retina/diagnóstico por imagen , Retinoblastoma/diagnóstico por imagen , Niño , Femenino , Fijación Ocular/fisiología , Humanos , Neoplasias de la Retina/fisiopatología , Retinoblastoma/fisiopatología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual/fisiología , Pruebas del Campo Visual , Campos Visuales/fisiología
11.
Invest Ophthalmol Vis Sci ; 59(8): 3330-3339, 2018 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-30025081

RESUMEN

Purpose: RPE65-associated Leber congenital amaurosis (RPE65-LCA) is an early-onset severe retinal dystrophy associated with progressive visual field loss. Phase I/II and III gene therapy trials have identified improved retinal sensitivity but little is known about the natural history of retinal sensitivity in RPE65-LCA. Methods: A total of 19 subjects (aged 9 to 23 years) undertook monocular full-field static perimetry of which 13 subjects were monitored longitudinally. Retinal sensitivity was measured as mean sensitivity (MS) and volumetrically quantified (in decibel-steradian) using visual field modeling and analysis software for the total (VTOT), central 30° (V30) and central 15° (V15) visual field. Correlation was evaluated between retinal sensitivity and age, best-corrected visual acuity (BCVA), contrast sensitivity, vision-related quality of life, and genotype. Test-retest reliability was also investigated. Results: V30 was identified to have a strong, weak, and moderate correlation with age, BCVA and contrast sensitivity respectively. Furthermore, V30 was identified as having a weak linear relationship with the mobility and independence domains of the vision-related quality of life questionnaire. Longitudinal analysis demonstrated a slow loss of retinal sensitivity in this cohort. Subjects with at least one RPE65 nonsense variant appeared to show greater progressive loss of retinal sensitivity in the second decade of life than those without. Conclusions: Volumetric assessment of central 30° visual field sensitivity, V30, is a useful independent measure of retinal function and, in our data, represented the best metric to monitor deterioration of retinal sensitivity in RPE65-LCA. Furthermore, functional correlation with genotype may enable more informed prognostic counseling. (ClinicalTrials.gov number, NCT02714816.)


Asunto(s)
Amaurosis Congénita de Leber/genética , Amaurosis Congénita de Leber/fisiopatología , Retina/fisiopatología , Campos Visuales/fisiología , cis-trans-Isomerasas/genética , Adolescente , Niño , Sensibilidad de Contraste/fisiología , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Masculino , Calidad de Vida , Encuestas y Cuestionarios , Agudeza Visual/fisiología , Pruebas del Campo Visual , Adulto Joven
12.
Ophthalmology ; 125(11): 1765-1775, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29884405

RESUMEN

PURPOSE: Transplantation of human embryonic stem cell (hESC)-derived retinal pigment epithelial (RPE) cells offers the potential for benefit in macular degeneration. Previous trials have reported improved visual acuity (VA), but lacked detailed analysis of retinal structure and function in the treated area. DESIGN: Phase 1/2 open-label dose-escalation trial to evaluate safety and potential efficacy (clinicaltrials.gov identifier, NCT01469832). PARTICIPANTS: Twelve participants with advanced Stargardt disease (STGD1), the most common cause of macular degeneration in children and young adults. METHODS: Subretinal transplantation of up to 200 000 hESC-derived RPE cells with systemic immunosuppressive therapy for 13 weeks. MAIN OUTCOME MEASURES: The primary end points were the safety and tolerability of hESC-derived RPE cell administration. We also investigated evidence of the survival of transplanted cells and measured retinal structure and function using microperimetry and spectral-domain OCT. RESULTS: Focal areas of subretinal hyperpigmentation developed in all participants in a dose-dependent manner in the recipient retina and persisted after withdrawal of systemic immunosuppression. We found no evidence of uncontrolled proliferation or inflammatory responses. Borderline improvements in best-corrected VA in 4 participants either were unsustained or were matched by a similar improvement in the untreated contralateral eye. Microperimetry demonstrated no evidence of benefit at 12 months in the 12 participants. In one instance at the highest dose, localized retinal thinning and reduced sensitivity in the area of hyperpigmentation suggested the potential for harm. Participant-reported quality of life using the 25-item National Eye Institute Visual Function Questionnaire indicated no significant change. CONCLUSIONS: Subretinal hyperpigmentation is consistent with the survival of viable transplanted hESC-derived RPE cells, but may reflect released pigment in their absence. The findings demonstrate the value of detailed analysis of spatial correlation of retinal structure and function in determining with appropriate sensitivity the impact of cell transplantation and suggest that intervention in early stage of disease should be approached with caution. Given the slow rate of progressive degeneration at this advanced stage of disease, any protection against further deterioration may be evident only after a more extended period of observation.


Asunto(s)
Células Madre Embrionarias Humanas/trasplante , Degeneración Macular/congénito , Epitelio Pigmentado de la Retina/trasplante , Adulto , Electrorretinografía , Femenino , Angiografía con Fluoresceína , Humanos , Inmunosupresores/uso terapéutico , Degeneración Macular/diagnóstico por imagen , Degeneración Macular/fisiopatología , Degeneración Macular/terapia , Masculino , Persona de Mediana Edad , Células Fotorreceptoras de Vertebrados/fisiología , Calidad de Vida , Perfil de Impacto de Enfermedad , Microscopía con Lámpara de Hendidura , Enfermedad de Stargardt , Tomografía de Coherencia Óptica , Agudeza Visual/fisiología , Pruebas del Campo Visual , Campos Visuales/fisiología
13.
Invest Ophthalmol Vis Sci ; 59(1): 85-93, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29332120

RESUMEN

Purpose: RPE65-associated Leber congenital amaurosis (RPE65-LCA) is a progressive severe retinal dystrophy with early profound dysfunction of rod photoreceptors followed by progressive cone photoreceptor degeneration. We aim to provide detailed information about how cone dysfunction affects color discrimination. Methods: Seven adults (aged 16-21) with RPE65-LCA underwent monocular color discrimination assessment using the Trivector and Ellipse versions of three computerized tests: Cambridge Colour Test (CCT), low vision version of the Cambridge Colour Test (lvvCCT), and the Universal Colour Discrimination Test (UCDT). For comparison, subjects were also tested using the American Optical Hardy Rand Rittler (AO-HRR) plates. Each assessment was repeated three times. Results: The Trivector version of the tests demonstrated that color discrimination along the tritan axis was undetectable in four subjects, and severely reduced in three subjects. These findings were confirmed by the Ellipse version of the tests. Color discrimination along the protan and deutan axes was evident but reduced in six of seven subjects. Four of seven subjects were unable to read any of the HRR plates. Conclusions: The computerized color vision tests adopted in this study provide detailed information about color discrimination in adult RPE65-LCA patients. The condition is associated with severe impairment of color discrimination, particularly along the tritan axis indicating possible early involvement of S-cones, with additional protan and deutan loss to a lesser extent. This psychophysical assessment strategy is likely to be valuable in measuring the impact of therapeutic intervention on cone function.


Asunto(s)
Percepción de Color/fisiología , Amaurosis Congénita de Leber/fisiopatología , Células Fotorreceptoras Retinianas Bastones/metabolismo , cis-trans-Isomerasas/genética , Adolescente , Pruebas de Percepción de Colores , Femenino , Variación Genética , Humanos , Amaurosis Congénita de Leber/genética , Amaurosis Congénita de Leber/metabolismo , Masculino , Adulto Joven , cis-trans-Isomerasas/metabolismo
14.
Transl Vis Sci Technol ; 6(3): 24, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28670502

RESUMEN

PURPOSE: We determine if visual field loss from glaucoma and/or measures of dry eye severity are associated with difficulty searching, as judged by slower search times on a text-based search task. METHODS: Glaucoma patients with bilateral visual field (VF) loss, patients with clinically significant dry eye, and normally-sighted controls were enrolled from the Wilmer Eye Institute clinics. Subjects searched three Yellow Pages excerpts for a specific phone number, and search time was recorded. RESULTS: A total of 50 glaucoma subjects, 40 dry eye subjects, and 45 controls completed study procedures. On average, glaucoma patients exhibited 57% longer search times compared to controls (95% confidence interval [CI], 26%-96%, P < 0.001), and longer search times were noted among subjects with greater VF loss (P < 0.001), worse contrast sensitivity (P < 0.001), and worse visual acuity (P = 0.026). Dry eye subjects demonstrated similar search times compared to controls, though worse Ocular Surface Disease Index (OSDI) vision-related subscores were associated with longer search times (P < 0.01). Search times showed no association with OSDI symptom subscores (P = 0.20) or objective measures of dry eye (P > 0.08 for Schirmer's testing without anesthesia, corneal fluorescein staining, and tear film breakup time). CONCLUSIONS: Text-based visual search is slower for glaucoma patients with greater levels of VF loss and dry eye patients with greater self-reported visual difficulty, and these difficulties may contribute to decreased quality of life in these groups. TRANSLATIONAL RELEVANCE: Visual search is impaired in glaucoma and dry eye groups compared to controls, highlighting the need for compensatory strategies and tools to assist individuals in overcoming their deficiencies.

15.
Invest Ophthalmol Vis Sci ; 58(5): 2652-2658, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28524928

RESUMEN

Purpose: To compare microperimetric sensitivity around the monocular preferred retinal locus (mPRL) in age-related macular degeneration (AMD) to normative data, and to describe the characteristics of visual field defects around the mPRL in AMD. Methods: Participants with AMD (total n = 185) were either prospectively recruited (n = 135) or retrospectively reviewed from an existing database (n = 50). Participants underwent microperimetry using a test pattern (37 point, 5° radius) centered on their mPRL. Sensitivities were compared to normative data by spatial interpolation, and conventional perimetric indices were calculated. The location of the mPRL relative to the fovea and to visual field defects was also investigated. Results: Location of mPRL varied approximately 15° horizontally and vertically. Visual field loss within 5° of the mPRL was considerable in the majority of participants (median mean deviation -14.7 dB, interquartile range [IQR] -19.6 to -9.6 dB, median pattern standard deviation 7.1 dB [IQR 4.8-9.0 dB]). Over 95% of participants had mean total deviation worse than -2 dB across all tested locations and similarly within 1° of their mPRL. A common pattern of placing the mPRL just foveal to a region of normal pattern deviation was found in 78% of participants. Total deviation was outside normal limits in this region in 68%. Conclusions: Despite altering fixation to improve vision, people with AMD exhibit considerable visual field loss at and around their mPRL. The location of the mPRL was typically just foveal to, but not within, a region of relatively normal sensitivity for the individual, suggesting that a combination of factors drives mPRL selection.


Asunto(s)
Degeneración Macular/fisiopatología , Retina/fisiopatología , Trastornos de la Visión/fisiopatología , Campos Visuales/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Degeneración Macular/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza Visual , Pruebas del Campo Visual
16.
Invest Ophthalmol Vis Sci ; 58(5): 2456-2462, 2017 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-28460047

RESUMEN

Purpose: To determine if the ability to divide attention affects the relationship between glaucoma-related vision loss and reading speed. Methods: Better eye mean deviation (MD), contrast sensitivity (CS), and better-eye distance visual acuity (VA) were measured in 28 participants with glaucoma and 21 controls. Reading speeds were assessed using MNRead, IRest, and sustained silent reading tests (words per minute, wpm). The ability to divide attention was measured using the Brief Test of Attention (BTA; scored 0-10). Multivariable linear regression models were used to determine the relationship between visual factors and reading speeds. Effect modification by BTA score (low BTA: <7; high BTA: ≥7) was examined. Results: Worse CS (per 0.1 log unit) was associated with slower maximum reading speed on MNRead test for participants with low BTA scores (ß = -9 wpm; 95% confidence interval [CI]: -16, -2), but not for those with high BTA scores (ß = -2 wpm; 95% CI: -6, +2). Similarly, for the IRest test, worse CS was associated with slower reading speeds (ß = -12 wpm; 95% CI: -20, -4) among those with low, but not high BTA scores (ß = -4 wpm; 95% CI: -10, +2). For the sustained silent reading test, glaucoma status (versus controls), worse visual field (VF) MD (per 5 dB), and worse CS were associated with 39%, 21%, and 19% slower reading speeds, respectively, for those with low BTA scores (P < 0.05), but these associations were not significant among those with high BTA scores (P > 0.1 for all). Conclusions: Decreased ability to divide attention, indicated by lower BTA scores, is associated with slower reading speeds in glaucoma with reduced CS and VF defects.


Asunto(s)
Atención , Sensibilidad de Contraste/fisiología , Glaucoma/fisiopatología , Lectura , Pruebas de Visión/métodos , Agudeza Visual , Campos Visuales/fisiología , Anciano , Femenino , Humanos , Masculino , Estudios Retrospectivos
17.
J Exp Psychol Hum Percept Perform ; 43(4): 729-740, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28182481

RESUMEN

Human adults can combine perceptual estimates from different senses to minimize uncertainty, by taking a reliability-weighted average (the maximum likelihood estimate, MLE). Although research has shown that healthy human adults reweight estimates as their reliability changes from one trial to the next, less is known about how humans adapt to gradual long-term changes in sensory reliability. This study assessed whether individuals diagnosed with progressive visual deterioration, due to retinal disease, combined auditory and visual cues to location according to optimal (MLE) predictions. Twelve patients with central visual loss, 10 patients with peripheral visual loss, and 12 normally sighted adults were asked to localize visual and/or auditory targets in central (1°-18°) and peripheral (36°-53°) locations. Normally sighted adults and patients with peripheral visual loss showed multisensory uncertainty reduction and cue weighting in line with MLE predictions. In contrast, patients with central visual loss did not weight estimates appropriately in either the center or the periphery, and failed to meet MLE predictions in the periphery. Our results show that one visual loss patient group succeeded at optimal cue combination, whereas the other patient group (patients with central vision loss) did not. We propose that sensory remapping due to changes in fixation behavior may contribute to apparent failures in the latter group. (PsycINFO Database Record


Asunto(s)
Percepción Auditiva/fisiología , Señales (Psicología) , Baja Visión/fisiopatología , Campos Visuales/fisiología , Percepción Visual/fisiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Retina/fisiopatología
18.
Sci Rep ; 7: 40567, 2017 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-28074913

RESUMEN

Psychophysical studies have frequently found that adults with normal hearing exhibit systematic errors (biases) in their auditory localisation judgments. Here we tested (i) whether systematic localisation errors could reflect reliance on prior knowledge, as has been proposed for other systematic perceptual biases, and (ii) whether auditory localisation biases can be reduced following training with accurate visual feedback. Twenty-four normal hearing participants were asked to localise the position of a noise burst along the azimuth before, during, and after training with visual feedback. Consistent with reliance on prior knowledge to reduce sensory uncertainty, we found that auditory localisation biases increased when auditory localisation uncertainty increased. Specifically, participants mis-localised auditory stimuli as being more eccentric than they were, and did so more when auditory uncertainty was greater. However, biases also increased with eccentricity, despite no corresponding increase in uncertainty, which is not readily explained by use of a simple prior favouring peripheral locations. Localisation biases decreased (improved) following training with visual feedback, but the reliability of the visual feedback stimulus did not change the effects of training. We suggest that further research is needed to identify alternative mechanisms, besides use of prior knowledge, that could account for increased perceptual biases under sensory uncertainty.


Asunto(s)
Percepción Auditiva , Sesgo , Incertidumbre , Estimulación Acústica , Adolescente , Retroalimentación , Femenino , Humanos , Masculino , Estimulación Luminosa , Adulto Joven
19.
Br J Ophthalmol ; 101(4): 481-486, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27450145

RESUMEN

BACKGROUND/AIMS: To evaluate the impact of dry eye on reading performance. METHODS: Out-loud and silent reading in patients with clinically significant dry eye (n=41) and controls (n=50) was evaluated using standardised texts. Dry eye measures included tear film break-up time, Schirmer's test and corneal epithelial staining. Symptoms were assessed by the Ocular Surface Disease Index (OSDI). RESULTS: The dry eye group had a greater proportion of women as compared with the control group but did not differ in age, race, education level or visual acuity (p≥0.05 for all). Out-loud reading speed averaged 148 words per minute (wpm) in dry eye subjects and 163 wpm in controls (p=0.006). Prolonged silent reading speed averaged 199 wpm in dry eye subjects versus 226 wpm in controls (p=0.03). In multivariable regression models, out-loud and sustained silent reading speeds were 10 wpm (95% CI -20 to -1 wpm, p=0.039) and 14% (95% CI -25% to -2%, p=0.032) slower, respectively, in dry eye subjects as compared with controls. Greater corneal staining was associated with slower out-loud (-2 wpm/1 unit increase in staining score, 95% CI =-3 to -0.3 wpm) and silent (-2%, 95% CI -4 to -0.6 wpm) reading speeds (p<0.02 for both). Significant interactions were found between OSDI score and word-specific features (longer and less commonly used words) on out-loud reading speed (p<0.05 for both). CONCLUSIONS: Dry eye is associated with slower out-loud and silent reading speeds, providing direct evidence regarding the functional impact of dry eye. Reading speed represents a measurable clinical finding that correlates directly with dry eye severity.


Asunto(s)
Síndromes de Ojo Seco/fisiopatología , Movimientos Oculares/fisiología , Lectura , Pruebas de Visión , Baja Visión/fisiopatología , Anciano , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Estudios Retrospectivos , Análisis y Desempeño de Tareas , Pruebas de Visión/métodos , Agudeza Visual
20.
Ophthalmologica ; 237(1): 42-54, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27997924

RESUMEN

PURPOSE: To assess the intrasession test-retest reliability of scotopic cyan and scotopic red fundus-controlled perimetry (FCP) in normal subjects using a modified MAIA "microperimeter" (macular integrity assessment) device. METHODS: Forty-seven normal eyes of 30 subjects (aged 33.8 years) underwent duplicate mesopic (achromatic stimuli, 400-800 nm), scotopic cyan (505 nm), and scotopic red (627 nm) FCP, using a grid of 49 stimuli over 14° of the central retina. Test-retest reliability for pointwise sensitivity (PWS), stability of fixation, reaction time and test duration were analyzed using mixed-effects models. RESULTS: PWS test-retest reliability was good among all 3 types of retinal sensitivity assessments (coefficient of repeatability of 4.75 dB for mesopic, 5.26 dB for scotopic cyan, and 4.06 dB for scotopic red testing). While the mean sensitivity decreased with eccentricity for both mesopic and scotopic red testing, it was highest at 7° eccentricity for the scotopic cyan assessment (p < 0.001). CONCLUSIONS: The modified MAIA device allows for reliable scotopic FCP in normal subjects. Our findings suggest that testing of scotopic cyan sensitivity largely reflects rod function.


Asunto(s)
Adaptación a la Oscuridad/fisiología , Mácula Lútea/diagnóstico por imagen , Visión Mesópica/fisiología , Escotoma/fisiopatología , Pruebas del Campo Visual/métodos , Campos Visuales/fisiología , Adulto , Femenino , Fondo de Ojo , Humanos , Masculino , Valores de Referencia , Reproducibilidad de los Resultados , Escotoma/diagnóstico , Agudeza Visual
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