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1.
Brain Behav ; 14(7): e3582, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38956813

RESUMO

BACKGROUND/OBJECTIVES: Stroke damage to the primary visual cortex induces large, homonymous visual field defects that impair daily living. Here, we asked if vision-related quality of life (VR-QoL) is impacted by time since stroke. SUBJECTS/METHODS: We conducted a retrospective meta-analysis of 95 occipital stroke patients (female/male = 26/69, 27-78 years old, 0.5-373.5 months poststroke) in whom VR-QoL was estimated using the National Eye Institute Visual Functioning Questionnaire (NEI-VFQ) and its 10-item neuro-ophthalmic supplement (Neuro10). Visual deficit severity was represented by the perimetric mean deviation (PMD) calculated from 24-2 Humphrey visual fields. Data were compared with published cohorts of visually intact controls. The relationship between VR-QoL and time poststroke was assessed across participants, adjusting for deficit severity and age with a multiple linear regression analysis. RESULTS: Occipital stroke patients had significantly lower NEI-VFQ and Neuro10 composite scores than controls. All subscale scores describing specific aspects of visual ability and functioning were impaired except for ocular pain and general health, which did not differ significantly from controls. Surprisingly, visual deficit severity was not correlated with either composite score, both of which increased with time poststroke, even when adjusting for PMD and age. CONCLUSIONS: VR-QoL appears to improve with time postoccipital stroke, irrespective of visual deficit size or patient age at insult. This may reflect the natural development of compensatory strategies and lifestyle adjustments. Thus, future studies examining the impact of rehabilitation on daily living in this patient population should consider the possibility that their VR-QoL may change gradually over time, even without therapeutic intervention.


Assuntos
Qualidade de Vida , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/complicações , Idoso , Adulto , Estudos Retrospectivos , Transtornos da Visão/fisiopatologia , Transtornos da Visão/etiologia , Lobo Occipital/fisiopatologia , Campos Visuais/fisiologia
2.
Eur J Sport Sci ; 24(7): 918-929, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38956797

RESUMO

Sports performance is relatively robust under high levels of binocular blur. However, the limited research studies investigating monocular impairments has shown it has a larger impact on sport performance. This research study is relevant for classification in sports for athletes with vision impairment (VI), where visual acuity (VA) from the better eye is used during classification. Across two experiments, we aimed to establish the point at which binocular and monocular impairments affected performance in a football penalty kick (PK) through simulating varying severities of degraded VA and contrast sensitivity (CS) in active football players. In experiment one, 25 footballers performed PKs as VA and CS were systematically decreased in both eyes, and in one condition, visual field (VF) was reduced. The most severe VA/CS condition and reduced VF significantly impacted outcome, ball velocity and placement (ball kicked closer to the centre of the goal) (p < 0.05). In experiment two, 29 different footballers performed PKs as VA and CS of only the dominant eye were systematically decreased and in one condition the dominant eye was occluded, and participants viewed their environment through the non-dominant eye (monocular viewing). No differences were observed when assessing monocular impairments influence on outcome, velocity and ball placement. PKs have a high resilience to VI, but binocular impairment has a more immediate effect, suggesting binocular measures should be used in classification processes in football.


Assuntos
Desempenho Atlético , Futebol , Visão Binocular , Acuidade Visual , Humanos , Futebol/fisiologia , Visão Binocular/fisiologia , Acuidade Visual/fisiologia , Masculino , Desempenho Atlético/fisiologia , Adulto Jovem , Adulto , Transtornos da Visão/fisiopatologia , Sensibilidades de Contraste/fisiologia , Visão Monocular/fisiologia , Campos Visuais/fisiologia
4.
Invest Ophthalmol Vis Sci ; 65(8): 15, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38975942

RESUMO

Purpose: To investigate the contributions of the microstructural and metabolic brain environment to glaucoma and their association with visual field (VF) loss patterns by using advanced diffusion magnetic resonance imaging (dMRI), proton magnetic resonance spectroscopy (MRS), and clinical ophthalmic measures. Methods: Sixty-nine glaucoma and healthy subjects underwent dMRI and/or MRS at 3 Tesla. Ophthalmic data were collected from VF perimetry and optical coherence tomography. dMRI parameters of microstructural integrity in the optic radiation and MRS-derived neurochemical levels in the visual cortex were compared among early glaucoma, advanced glaucoma, and healthy controls. Multivariate regression was used to correlate neuroimaging metrics with 16 archetypal VF loss patterns. We also ranked neuroimaging, ophthalmic, and demographic attributes in terms of their information gain to determine their importance to glaucoma. Results: In dMRI, decreasing fractional anisotropy, radial kurtosis, and tortuosity and increasing radial diffusivity correlated with greater overall VF loss bilaterally. Regionally, decreasing intra-axonal space and extra-axonal space diffusivities correlated with greater VF loss in the superior-altitudinal area of the right eye and the inferior-altitudinal area of the left eye. In MRS, both early and advanced glaucoma patients had lower gamma-aminobutyric acid (GABA), glutamate, and choline levels than healthy controls. GABA appeared to associate more with superonasal VF loss, and glutamate and choline more with inferior VF loss. Choline ranked third for importance to early glaucoma, whereas radial kurtosis and GABA ranked fourth and fifth for advanced glaucoma. Conclusions: Our findings highlight the importance of non-invasive neuroimaging biomarkers and analytical modeling for unveiling glaucomatous neurodegeneration and how they reflect complementary VF loss patterns.


Assuntos
Tomografia de Coerência Óptica , Testes de Campo Visual , Campos Visuais , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Campos Visuais/fisiologia , Tomografia de Coerência Óptica/métodos , Idoso , Transtornos da Visão/fisiopatologia , Transtornos da Visão/metabolismo , Imagem de Difusão por Ressonância Magnética , Glaucoma/fisiopatologia , Glaucoma/metabolismo , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Glaucoma de Ângulo Aberto/metabolismo , Glaucoma de Ângulo Aberto/fisiopatologia , Córtex Visual/metabolismo , Córtex Visual/diagnóstico por imagem , Espectroscopia de Prótons por Ressonância Magnética , Adulto , Pressão Intraocular/fisiologia
5.
BMJ Open Ophthalmol ; 9(1)2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009464

RESUMO

OBJECTIVE: To investigate differential associations of traditional and novel adiposity indices with visual impairment (VI) in the middle-aged and older Chinese population. METHODS AND ANALYSIS: Based on the China Health and Retirement Longitudinal Study, 7750 Chinese older adults aged over 45 were included at baseline 2011, and 4133 participants who accomplished all three interviews from 2011 to 2015 were adapted for longitudinal analyses. We enrolled six adiposity indices, including the body mass index (BMI), waist-to-height ratio (WHtR), weight-adjusted-waist index (WWI), a body shape index (ABSI), body roundness index (BRI) and conicity index (ConI). Visual status and other covariates included sociodemographic characteristics, medical supports and lifestyle-related factors. Cross-sectional correlations were assessed using univariate and multivariate logistic regression analyses. For longitudinal analysis, generalised linear models with generalised estimating equations were used to determine the association between time-varying adiposity and visual status. RESULTS: Higher levels of WHtR/WWI/ABSI/BRI/ConI were significantly associated with an increased prevalence of VI, whereas a higher BMI was associated with a decreased prevalence of VI. Only WWI was significantly related to the prevalence of VI after adjustment for multiple confounders in both cross-sectional and longitudinal analyses (all p values <0.05). The multivariable-adjusted OR (95% CI) of VI associated with the highest (vs lowest) quintile of WWI was 1.900 (1.407 to 2.565). CONCLUSION: WWI is a reliable alternative adiposity index that exhibits a dose-response association with the prevalence of VI in the Chinese population. The WWI-VI correlation may eliminate the obesity paradox in the ophthalmic epidemiological area and indicate the detrimental impact of changes in body composition on VI.


Assuntos
Adiposidade , Índice de Massa Corporal , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Estudos Transversais , China/epidemiologia , Prevalência , Transtornos da Visão/epidemiologia , Transtornos da Visão/fisiopatologia , Fatores de Risco , Antropometria , Estudos Longitudinais , População do Leste Asiático
6.
In Vivo ; 38(4): 1947-1956, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38936949

RESUMO

BACKGROUND/AIM: To investigate the treatment outcomes and determinants of prognosis in patients experiencing visual acuity (VA) deterioration due to inflammatory isolated sphenoid sinus disease (ISSD) who underwent endonasal endoscopic surgery (EES). PATIENTS AND METHODS: Thirteen patients with 14 lesions treated with EES between March 2010 and April 2022 were included. Evaluation included improvements in VA using the logarithm of the minimum angle of resolution (LogMAR) scale, resolution rates of associated symptoms, and identification of factors predicting VA recovery. A literature review was conducted to assess the outcomes for ISSD-related VA impairments. RESULTS: The most common etiology is mycetoma (n=5), followed by an equal representation of mucocele and sphenoiditis (n=4). The mean interval from symptom onset to intervention was 4.7 months, with an average follow-up duration of 14.4 months. Seven eyes exhibited preoperative VA of 2.1 LogMAR or worse, with diplopia/ptosis (n=8) and headache (n=5) being the predominant co-occurring symptoms. After surgery, all ancillary symptoms improved, with an overall VA recovery rate of 87.5% (improvement more than 0.2 logMAR units). Mucocele exhibited the best improvements, whereas sphenoiditis showed the least progress (p=0.021). Poor baseline VA (p=0.026) and combined diplopia/ptosis (p=0.029) were identified as negative prognostic factors for VA recovery. CONCLUSION: Our findings suggest a favorable prognosis for VA recovery following EES in patients with inflammatory ISSDs, with response variations based on disease entity. However, further research is needed to personalize therapeutic strategies for enhanced outcomes.


Assuntos
Acuidade Visual , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Resultado do Tratamento , Seio Esfenoidal/cirurgia , Sinusite Esfenoidal/complicações , Sinusite Esfenoidal/cirurgia , Sinusite Esfenoidal/fisiopatologia , Endoscopia/métodos , Prognóstico , Adulto Jovem , Inflamação , Transtornos da Visão/etiologia , Transtornos da Visão/fisiopatologia
7.
Adv Gerontol ; 37(1-2): 72-79, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38944776

RESUMO

A study was conducted to investigate the associations of the diseases of the organ of vision and its accessory apparatus with anxiety and depression in the elderly people. The study included 678 participants of the ESSE-RF3 population study in the Arkhangelsk region in the age of 60-74 years. We used a questionnaire, including the hospital scale of anxiety and depression score (HADS), and the assessment of the ophthalmological status. It was found that all the study participants had diseases of the visual organ. Elevated depression scores were associated with sex, age, marital status (being single), and disability, elevated anxiety scores - with sex. The scores on the anxiety scale were on average 25% higher in participants whose visual acuity decreased to 0,5 units, and showed no independent associations with diagnosed ophthalmological diseases. The scores on the depression scale were on average 33% higher in participants with visual acuity 0,5 units, and 22% higher in the presence of retinopathy. In conclusion, anxiety and depression in the elderly people were more associated with visual deficits rather than with the presence of ophthalmological diseases underlying a decrease in functional status.


Assuntos
Ansiedade , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Federação Russa/epidemiologia , Ansiedade/epidemiologia , Ansiedade/diagnóstico , Ansiedade/psicologia , Acuidade Visual , Depressão/epidemiologia , Depressão/diagnóstico , Depressão/psicologia , Depressão/etiologia , Oftalmopatias/epidemiologia , Oftalmopatias/diagnóstico , Oftalmopatias/psicologia , Oftalmopatias/fisiopatologia , Inquéritos e Questionários , Transtornos da Visão/epidemiologia , Transtornos da Visão/psicologia , Transtornos da Visão/fisiopatologia , Transtornos da Visão/diagnóstico
8.
Magn Reson Med Sci ; 23(3): 316-340, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38866532

RESUMO

Diffusion-weighted MRI (dMRI) provides a unique non-invasive view of human brain tissue properties. The present review article focuses on tractometry analysis methods that use dMRI to assess the properties of brain tissue within the long-range connections comprising brain networks. We focus specifically on the major white matter tracts that convey visual information. These connections are particularly important because vision provides rich information from the environment that supports a large range of daily life activities. Many of the diseases of the visual system are associated with advanced aging, and tractometry of the visual system is particularly important in the modern aging society. We provide an overview of the tractometry analysis pipeline, which includes a primer on dMRI data acquisition, voxelwise model fitting, tractography, recognition of white matter tracts, and calculation of tract tissue property profiles. We then review dMRI-based methods for analyzing visual white matter tracts: the optic nerve, optic tract, optic radiation, forceps major, and vertical occipital fasciculus. For each tract, we review background anatomical knowledge together with recent findings in tractometry studies on these tracts and their properties in relation to visual function and disease. Overall, we find that measurements of the brain's visual white matter are sensitive to a range of disorders and correlate with perceptual abilities. We highlight new and promising analysis methods, as well as some of the current barriers to progress toward integration of these methods into clinical practice. These barriers, such as variability in measurements between protocols and instruments, are targets for future development.


Assuntos
Vias Visuais , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Vias Visuais/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Transtornos da Visão/diagnóstico por imagem , Transtornos da Visão/fisiopatologia
11.
J Vis ; 24(6): 3, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38837169

RESUMO

The primary symptom of visual snow syndrome (VSS) is the unremitting perception of small, flickering dots covering the visual field. VSS is a serious but poorly understood condition that can interfere with daily tasks. Several studies have provided qualitative data about the appearance of visual snow, but methods to quantify the symptom are lacking. Here, we developed a task in which participants with VSS adjusted parameters of simulated visual snow on a computer monitor until the simulation matched their internal visual snow. On each trial, participants (n = 31 with VSS) modified the size, density, update speed, and contrast of the simulation. Participants' settings were highly reliable across trials (intraclass correlation coefficients > 0.89), and they reported that the task was effective at stimulating their visual snow. On average, visual snow was very small (less than 2 arcmin in diameter), updated quickly (mean temporal frequency = 18.2 Hz), had low density (mean snow elements vs. background = 2.87%), and had low contrast (average root mean square contrast = 2.56%). Our task provided a quantitative assessment of visual snow percepts, which may help individuals with VSS communicate their experience to others, facilitate assessment of treatment efficacy, and further our understanding of the trajectory of symptoms, as well as the neural origins of VSS.


Assuntos
Campos Visuais , Humanos , Adulto , Masculino , Feminino , Campos Visuais/fisiologia , Adulto Jovem , Estimulação Luminosa/métodos , Pessoa de Meia-Idade , Sensibilidades de Contraste/fisiologia , Transtornos da Percepção/fisiopatologia , Transtornos da Percepção/etiologia , Percepção Visual/fisiologia , Simulação por Computador , Transtornos da Visão/fisiopatologia
12.
Curr Neurol Neurosci Rep ; 24(8): 273-284, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38907811

RESUMO

PURPOSE OF REVIEW: To review the literature on visual dysfunction in dementia with Lewy bodies (DLB), including its mechanisms and clinical implications. RECENT FINDINGS: Recent studies have explored novel aspects of visual dysfunction in DLB, including visual texture agnosia, mental rotation of 3-dimensional drawn objects, and reading fragmented letters. Recent studies have shown parietal and occipital hypoperfusion correlating with impaired visuoconstruction performance. While visual dysfunction in clinically manifest DLB is well recognized, recent work has focused on prodromal or mild cognitive impairment (MCI) due to Lewy body pathology with mixed results. Advances in retinal imaging have recently led to the identification of abnormalities such as parafoveal thinning in DLB. Patients with DLB experience impairment in color perception, form and object identification, space and motion perception, visuoconstruction tasks, and illusions in association with visual cortex and network dysfunction. These symptoms are associated with visual hallucinations, driving impairment, falls, and other negative outcomes.


Assuntos
Doença por Corpos de Lewy , Transtornos da Visão , Humanos , Doença por Corpos de Lewy/fisiopatologia , Doença por Corpos de Lewy/complicações , Transtornos da Visão/etiologia , Transtornos da Visão/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/etiologia , Percepção Visual/fisiologia
13.
J AAPOS ; 28(3): 103933, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729256

RESUMO

PURPOSE: To assess the feasibility and performance of Vivid Vision Perimetry (VVP), a new virtual reality (VR)-based visual field platform. METHODS: Children 7-18 years of age with visual acuity of 20/80 or better undergoing Humphrey visual field (HVF) testing were recruited to perform VVP, a VR-based test that uses suprathreshold stimuli to test 54 field locations and calculates a fraction seen score. Pearson correlation coefficients were calculated to evaluate correlation between HVF mean sensitivity and VVP mean fraction seen scores. Participants were surveyed regarding their experience. RESULTS: A total of 37 eyes of 23 participants (average age, 12.9 ± 3.1 years; 48% female) were included. All participants successfully completed VVP testing. Diagnoses included glaucoma (12), glaucoma suspect (7), steroid-induced ocular hypertension (3), and craniopharyngioma (1). Sixteen participants had prior HVF experience, and none had prior VVP experience, although 7 had previously used VR. Of the 23 HVF tests performed, 9 (39%) were unreliable due to fixation losses, false positives, or false negatives. Similarly, 35% of VVP tests were unreliable (as defined by accuracy of blind spot detection). Excluding unreliable HVF tests, the correlation between HVF average mean sensitivity and VVP mean fraction seen score was 0.48 (P = 0.02; 95% CI, 0.09-0.74). When asked about preference for the VVP or HVF examination, all participants favored the VVP, and 70% were "very satisfied" with VVP. CONCLUSIONS: In our cohort of 23 pediatric subjects, VVP proved to be a clinically feasible VR-based visual field testing, which was uniformly preferred over HVF.


Assuntos
Estudos de Viabilidade , Realidade Virtual , Acuidade Visual , Testes de Campo Visual , Campos Visuais , Humanos , Testes de Campo Visual/métodos , Criança , Feminino , Masculino , Projetos Piloto , Adolescente , Campos Visuais/fisiologia , Acuidade Visual/fisiologia , Glaucoma/diagnóstico , Glaucoma/fisiopatologia , Reprodutibilidade dos Testes , Transtornos da Visão/diagnóstico , Transtornos da Visão/fisiopatologia , Hipertensão Ocular/diagnóstico , Hipertensão Ocular/fisiopatologia
14.
J AAPOS ; 28(3): 103930, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719139

RESUMO

PURPOSE: To assess the utility of 3D, tablet-based, glasses-free Accurate STEReotest (ASTEROID) in children compared with the Titmus test. METHODS: Children aged 5-13 years were enrolled in a single-center, nonrandomized, observational comparison study and analyzed by age (5-7 vs 8-13 years) and visual acuity (20/25 or better in both eyes vs abnormal). Each participant underwent both the ASTEROID and Titmus stereoacuity tests. Stereoacuity was defined as fine (≤60 arcsec), moderate (61-200 arcsec), coarse (201-1199 arcsec), or very coarse to nil (≥1200 arcsec). Agreement between the tests was assessed using a weighted kappa (κ) statistic based on all four categories. RESULTS: A total of 112 children were included: 28 aged 5-7 with normal visual acuity, 30 aged 5-7 with abnormal visual acuity, 34 aged 8-13 with normal visual acuity, and 20 aged 8-13 with abnormal visual acuity. Mean ASTEROID score was 688 ± 533 arcsec (range, 13-1200 arcsec). Agreement between ASTEROID and Titmus test scores for participants overall was moderate (κ = 0.52). By subgroup, agreement was fair for children 5-7 with abnormal visual acuity (κ = 0.31), moderate for children 5-7 with normal visual acuity (κ = 0.47) and children 8-13 with normal visual acuity (κ = 0.42), and substantial for children 8-13 with abnormal visual acuity (κ = 0.76). Where ASTEROID and Titmus score group varied, ASTEROID score was poorer in 94% (47/50) of cases. CONCLUSIONS: ASTEROID is a digital, tablet-based test that evaluates global stereopsis, does not require glasses, and provides a continuum of scores. Among children, ASTEROID has good agreement with the Titmus test; however, it may be more sensitive at detecting stereovision deficits. Further study is necessary to determine which test is more accurate.


Assuntos
Computadores de Mão , Percepção de Profundidade , Testes Visuais , Acuidade Visual , Humanos , Criança , Acuidade Visual/fisiologia , Testes Visuais/métodos , Pré-Escolar , Adolescente , Feminino , Masculino , Percepção de Profundidade/fisiologia , Transtornos da Visão/fisiopatologia , Transtornos da Visão/diagnóstico , Reprodutibilidade dos Testes , Imageamento Tridimensional
15.
Ophthalmic Physiol Opt ; 44(5): 840-853, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757445

RESUMO

PURPOSE: To compare the objective performance, acceptance and usability of head-mounted displays (HMDs) to provide evidence-based data that could be used to increase the efficiency of device referrals based upon a person's vision loss and functional needs. METHODS: A cross-sectional, counterbalanced, individually controlled crossover study was performed on 15 adults with various eye conditions. Performance was measured when using four HMDs: eSight4, Eyedaptic EYE3, Eyedaptic EYE4 and IrisVision Inspire. Performance on clinical visual acuity tests and contrast were assessed, as well as vision-related activities of daily living (ADL) which were divided into three categories: Reading, Searching & Identifying and Eye-hand Coordination. User-experience was also assessed. Logistic regression analyses, Friedman one-way repeated measure analyses of variance by ranks and multivariate permutation testing were used for analysis. RESULTS: There was a significant improvement in visual acuity when using all devices. For contrast tasks, only the eSight4 and Eyedaptic EYE3 improved performance relative to baseline. For most Reading and Searching & Identifying tasks, the odds of being able to perform the tasks were significantly higher while using the devices. However, the actual performance with most devices (e.g., number of words read or reading speed) did not improve significantly over baseline for most tasks. For the Eye-hand Coordination tasks, participants performed equivalent to or significantly poorer than baseline when using the devices. No demographic or clinical predictors of outcomes were identified. Participants expressed dissatisfaction with the devices' effectiveness, acceptability and usability. CONCLUSIONS: While performance on clinical tests was better when using the devices, performance on most real-world ADLs was equal to or worse than baseline. No single device improved performance on all tasks, and performance on any one task was not improved with all the devices. The overall dissatisfaction with the devices paralleled the lack of objective improvement in the performance of real-world tasks.


Assuntos
Atividades Cotidianas , Estudos Cross-Over , Acuidade Visual , Humanos , Masculino , Feminino , Acuidade Visual/fisiologia , Pessoa de Meia-Idade , Estudos Transversais , Adulto , Idoso , Baixa Visão/fisiopatologia , Baixa Visão/reabilitação , Pessoas com Deficiência Visual/reabilitação , Transtornos da Visão/fisiopatologia , Leitura
17.
Brain Behav ; 14(5): e3525, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38773793

RESUMO

INTRODUCTION: Visual field defects (VFDs) represent a debilitating poststroke complication, characterized by unseen parts of the visual field. Visual perceptual learning (VPL), involving repetitive visual training in blind visual fields, may effectively restore visual field sensitivity in cortical blindness. This current multicenter, double-blind, randomized, controlled clinical trial investigated the efficacy and safety of VPL-based digital therapeutics (Nunap Vision [NV]) for treating poststroke VFDs. METHODS: Stroke outpatients with VFDs (>6 months after stroke onset) were randomized into NV (defective field training) or Nunap Vision-Control (NV-C, central field training) groups. Both interventions provided visual perceptual training, consisting of orientation, rotation, and depth discrimination, through a virtual reality head-mounted display device 5 days a week for 12 weeks. The two groups received VFD assessments using Humphrey visual field (HVF) tests at baseline and 12-week follow-up. The final analysis included those completed the study (NV, n = 40; NV-C, n = 35). Efficacy measures included improved visual area (sensitivity ≥6 dB) and changes in the HVF scores during the 12-week period. RESULTS: With a high compliance rate, NV and NV-C training improved the visual areas in the defective hemifield (>72 degrees2) and the whole field (>108 degrees2), which are clinically meaningful improvements despite no significant between-group differences. According to within-group analyses, mean total deviation scores in the defective hemifield improved after NV training (p = .03) but not after NV-C training (p = .12). CONCLUSIONS: The current trial suggests that VPL-based digital therapeutics may induce clinically meaningful visual improvements in patients with poststroke VFDs. Yet, between-group differences in therapeutic efficacy were not found as NV-C training exhibited unexpected improvement comparable to NV training, possibly due to learning transfer effects.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Realidade Virtual , Campos Visuais , Percepção Visual , Humanos , Método Duplo-Cego , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Campos Visuais/fisiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/fisiopatologia , Percepção Visual/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Reabilitação do Acidente Vascular Cerebral/instrumentação , Aprendizagem/fisiologia , Transtornos da Visão/etiologia , Transtornos da Visão/reabilitação , Transtornos da Visão/terapia , Transtornos da Visão/fisiopatologia
18.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38795357

RESUMO

Visuospatial processing impairments are prevalent in individuals with cerebral visual impairment (CVI) and are typically ascribed to "dorsal stream dysfunction" (DSD). However, the contribution of other cortical regions, including early visual cortex (EVC), frontal cortex, or the ventral visual stream, to such impairments remains unknown. Thus, here, we examined fMRI activity in these regions, while individuals with CVI (and neurotypicals) performed a visual search task within a dynamic naturalistic scene. First, behavioral performance was measured with eye tracking. Participants were instructed to search and follow a walking human target. CVI participants took significantly longer to find the target, and their eye gaze patterns were less accurate and less precise. Second, we used the same task in the MRI scanner. Along the dorsal stream, activation was reduced in CVI participants, consistent with the proposed DSD in CVI. Intriguingly, however, visual areas along the ventral stream showed the complete opposite pattern, with greater activation in CVI participants. In contrast, we found no differences in either EVC or frontal cortex between groups. These results suggest that the impaired visuospatial processing abilities in CVI are associated with differential recruitment of the dorsal and ventral visual streams, likely resulting from impaired selective attention.


Assuntos
Imageamento por Ressonância Magnética , Percepção Espacial , Córtex Visual , Humanos , Masculino , Feminino , Adulto , Percepção Espacial/fisiologia , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiopatologia , Córtex Visual/fisiologia , Vias Visuais/diagnóstico por imagem , Vias Visuais/fisiologia , Vias Visuais/fisiopatologia , Adulto Jovem , Transtornos da Visão/fisiopatologia , Mapeamento Encefálico , Pessoa de Meia-Idade , Percepção Visual/fisiologia , Estimulação Luminosa/métodos
19.
Invest Ophthalmol Vis Sci ; 65(5): 38, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38787547

RESUMO

Purpose: Visual snow is the hallmark of the neurological condition visual snow syndrome (VSS) but the characteristics of the visual snow percept remain poorly defined. This study aimed to quantify its appearance, interobserver variability, and effect on measured visual performance and self-reported visual quality. Methods: Twenty-three participants with VSS estimated their visual snow dot size, separation, luminance, and flicker rate by matching to a simulation. To assess whether visual snow masks vision, we compared pattern discrimination thresholds for textures that were similar in spatial scale to visual snow as well as more coarse than visual snow, in participants with VSS, and with and without external noise simulating visual snow in 23 controls. Results: Mean and 95% confidence intervals for visual snow appearance were: size (6.0, 5.8-6.3 arcseconds), separation (2.0, 1.7-2.3 arcmin), luminance (72.4, 58.1-86.8 cd/m2), and flicker rate (25.8, 18.9-32.8 frames per image at 120 hertz [Hz]). Participants with finer dot spacing estimates also reported greater visibility of their visual snow (τb = -0.41, 95% confidence interval [CI] = -0.62 to -0.13, P = 0.01). In controls, adding simulated fine-scale visual snow to textures increased thresholds for fine but not coarse textures (F(1, 22) = 4.98, P = 0.036, ηp2 = 0.19). In VSS, thresholds for fine and coarse textures were similar (t(22) = 0.54, P = 0.60), suggesting that inherent visual snow does not act like external noise in controls. Conclusions: Our quantitative estimates of visual snow constrain its likely neural origins, may aid differential diagnosis, and inform future investigations of how it affects vision. Methods to quantify visual snow are needed for evaluation of potential treatments.


Assuntos
Acuidade Visual , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Acuidade Visual/fisiologia , Adulto Jovem , Limiar Sensorial/fisiologia , Transtornos da Visão/fisiopatologia , Transtornos da Visão/diagnóstico , Idoso , Percepção Visual/fisiologia , Variações Dependentes do Observador , Reconhecimento Visual de Modelos/fisiologia , Transtornos da Percepção
20.
Invest Ophthalmol Vis Sci ; 65(5): 20, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38727692

RESUMO

Purpose: Vision-degrading myodesopsia (VDM) from vitreous floaters significantly degrades vision and impacts visual quality of life (VQOL), but the relationship to light scattering is poorly understood. This study compared in vitro measures of light scatter and transmission in surgically excised human vitreous to preoperative indexes of vitreous structure, visual function, and VQOL. Methods: Pure vitreous collected during vitrectomy from 8 patients with VDM had wide-angle straylight measurements and dark-field imaging, performed within 36 hours of vitrectomy. Preoperative VQOL assessment with VFQ-25, contrast sensitivity (CS) measurements with Freiburg acuity contrast testing, and quantitative ultrasonography were compared to light scattering and transmission in vitro. Results: All indices of vitreous echodensity in vivo correlated positively with straylight at 0.5° (R = 0.708 to 0.775, P = 0.049 and 0.024, respectively). Straylight mean scatter index correlated with echodensity (R = 0.71, P = 0.04) and VQOL (R = -0.82, P = 0.0075). Dark-field measures in vitro correlated with degraded CS in vivo (R = -0.69, P = 0.04). VQOL correlated with straylight mean scatter index (R = -0.823, P = 0.012). Conclusions: Increased vitreous echodensity in vivo is associated with more straylight scattering in vitro, validating ultrasonography as a clinical surrogate for light scattering. Contrast sensitivity in vivo is more degraded in the presence of dark-field scattering in vitro and VQOL is decreased in patients whose vitreous has increased light scattering. These findings could form the basis for the development of optical corrections for VDM or support new laser treatments, as well as novel pharmacotherapy.


Assuntos
Sensibilidades de Contraste , Luz , Espalhamento de Radiação , Acuidade Visual , Vitrectomia , Corpo Vítreo , Humanos , Corpo Vítreo/diagnóstico por imagem , Feminino , Masculino , Pessoa de Meia-Idade , Acuidade Visual/fisiologia , Sensibilidades de Contraste/fisiologia , Idoso , Qualidade de Vida , Transtornos da Visão/fisiopatologia , Adulto , Ultrassonografia , Oftalmopatias/fisiopatologia , Oftalmopatias/diagnóstico por imagem
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