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1.
Am J Ophthalmol ; 210: 125-135, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31626763

RESUMEN

PURPOSE: To examine an image remapping method for peripheral visual field (VF) expansion with novel virtual reality digital spectacles (DSpecs) to improve visual awareness in glaucoma patients. DESIGN: Prospective case series. METHODS: Monocular peripheral VF defects were measured and defined with a head-mounted display diagnostic algorithm. The monocular VF was used to calculate remapping parameters with a customized algorithm to relocate and resize unseen peripheral targets within the remaining VF. The sequence of monocular VF was tested and customized image remapping was carried out in 23 patients with typical glaucomatous defects. Test images demonstrating roads and cars were used to determine increased awareness of peripheral hazards while wearing the DSpecs. Patients' scores in identifying and counting peripheral objects with the remapped images were the main outcome measurements. RESULTS: The diagnostic monocular VF testing algorithm was comparable to standard automated perimetric determination of threshold sensitivity based on point-by-point assessment. Eighteen of 23 patients (78%) could identify safety hazards with the DSpecs that they could not previously. The ability to identify peripheral objects improved with the use of the DSpecs (P = 0.024, chi-square test). Quantification of the number of peripheral objects improved with the DSpecs (P = 0.0026, Wilcoxon rank sum test). CONCLUSIONS: These novel spectacles may enhance peripheral objects awareness by enlarging the functional field of view in glaucoma patients.


Asunto(s)
Anteojos , Glaucoma/complicaciones , Escotoma/rehabilitación , Realidad Virtual , Campos Visuales/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Escotoma/fisiopatología , Pruebas del Campo Visual
2.
Am J Ophthalmol ; 210: 136-145, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31606442

RESUMEN

PURPOSE: To assess the efficacy of novel Digital spectacles (DSpecs) to improve mobility of patients with peripheral visual field (VF) loss. DESIGN: Prospective case series. METHODS: Binocular VF defects were quantified with the DSpecs testing strategy. An algorithm was implemented that generated personalized visual augmentation profiles based on the measured VF. These profiles were achieved by relocating and resizing video signals to fit within the remaining VF in real time. Twenty patients with known binocular VF defects were tested using static test images, followed by dynamic walking simulations to determine if they could identify objects and avoid obstacles in an environment mimicking a real-life situation. The effect of the DSpecs were assessed for visual/hand coordination with object-grasping tests. Patients performed these tests with and without the DSpecs correction profile. RESULTS: The diagnostic binocular VF testing with the DSpecs was comparable to the integrated monocular standard automated perimetry based on point-by-point assessment with a mismatch error of 7.0%. Eighteen of 20 patients (90%) could identify peripheral objects in test images with the DSpecs that they could not previously. Visual/hand coordination was successful for 17 patients (85%) from the first trial. The object-grasping performance improved to 100% by the third trial. Patient performance, judged by finding and identifying objects in the periphery in a simulated walking environment, was significantly better with the DSpecs (P = 0.02, Wilcoxon rank sum test). CONCLUSIONS: DSpecs may improve mobility by facilitating the ability of patients to better identify moving peripheral hazardous objects.


Asunto(s)
Anteojos , Glaucoma/complicaciones , Escotoma/rehabilitación , Realidad Virtual , Campos Visuales/fisiología , Caminata , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Escotoma/fisiopatología
3.
BMC Ophthalmol ; 17(1): 149, 2017 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-28830379

RESUMEN

BACKGROUND: To evaluate functional visual parameters using photocromic and selective blue-violet light filtering spectacle lenses in patients affected by central or peripheral scotoma due to retinal diseases. Sixty patients were enrolled in this study: 30 patients affected by central scotoma, group 1, and 30 affected by peripheral scotoma, group 2. Black on White Best Corrected Visual Acuity (BW-BCVA), White on Black Best Corrected Visual Acuity (WB-BCVA), Mars Contrast Sensitivity (CS) and a Glare Test (GT) were performed to all patients. Test results with blue-violet filter, a short-pass yellow filter and with no filters were compared. RESULTS: All scores from test results increased significantly with blue-violet filters for all patients. The mean BW-BCVA increased from 0.30 ± 0.20 to 0.36 ± 0.21 decimals in group 1 and from 0.44 ± 0.22 to 0.51 ± 0.23 decimals in group 2 (Mean ± SD, p < 0.0001 in both cases). The mean WB-BCVA increased from 0.31 ± 0.19 to 0.38 ± 0.23 decimals in group 1 and from 0.46 ± 0.20 to 0.56 ± 0.22 decimals in group 2 (Mean ± SD, p < 0.0001 in both cases). The letter count for the CS test increased from 26.7 ± 7.9 to 30.06 ± 7.8 in group 1 (Mean ± SD, p = 0.0005) and from 31.5 ± 7.6 to 33.72 ± 7.3 in group 2 (Mean ± SD, p = 0.031). GT was significantly reduced: the letter count increased from 20.93 ± 5.42 to 22.82 ± 4.93 in group 1 (Mean ± SD, p < 0.0001) and from 24.15 ± 5.5 to 25.97 ± 4.7 in group 2 (Mean ± SD, p < 0.0001). Higher scores were recorded with the Blue filter compared to Yellow filter in all tests (p < 0.05). No significant differences in any test results could be detected between the Yellow filter and the No filter condition. CONCLUSIONS: The use of a combination of photocromic lens with a selective blue-violet light filter showed functional benefit in all evaluated patients.


Asunto(s)
Anteojos , Luz , Enfermedades de la Retina/rehabilitación , Escotoma/rehabilitación , Adulto , Anciano , Anciano de 80 o más Años , Sensibilidad de Contraste/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Retina/fisiopatología , Escotoma/fisiopatología , Agudeza Visual/fisiología
4.
Curr Eye Res ; 42(9): 1260-1268, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28632405

RESUMEN

PURPOSE: To evaluate the efficacy of a reading rehabilitation program (RRP) in patients with central visual loss (CVL) and assess the impact of the RRP on the quality of life (QoL). METHODS: The RRP included four in-office and 39 in-home training sessions over 6 weeks. Reading speed, duration, and font size were evaluated during each in-office session. The subjective perception of the QoL was assessed before and after the RRP using the short version of a questionnaire (World Health Organization Quality of Life). A control group who received advice about ocular conditions and low-vision aids also was included. RESULTS: Seventeen patients with Stargardt's disease (STGD), 11 with adult-onset foveomacular vitelliform dystrophy (AFVD), and eight with myopic macular degeneration (MMD) were included. The control group included five patients each with STGD, AFVD, and MMD. The respective mean corrected distance visual acuities (VAs) in patients with STGD, AFVD, MMD, and the control group were 0.57 ± 0.38, 0.51 ± 0.38, 0.49 ± 0.24, and 0.55 ± 0.25 logarithm of the minimum angle of resolution; the mean corrected near VAs were 0.89 ± 0.20, 1.08 ± 0.17, 0.99 ± 0.34, and 1.18 ± 0.37 (M notation) using low-vision aids. The reading speed, duration, and font size improved in all groups. The RRP groups obtained (p ≤ 0.01) greater improvements than the control group in each reading performance variable assessed. Patients with STGD obtained greater improvements in the subjective evaluation; the control group did not obtain noteworthy improvement in any domain. CONCLUSIONS: The RRP improved reading performance in patients with CVL and positively impacted the subjective perception of the QoL.


Asunto(s)
Calidad de Vida , Lectura , Escotoma/rehabilitación , Agudeza Visual , Anciano , Femenino , Humanos , Masculino , Escotoma/fisiopatología , Encuestas y Cuestionarios , Degeneración Macular Húmeda
6.
Invest Ophthalmol Vis Sci ; 56(12): 7169-78, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26540655

RESUMEN

PURPOSE: People with central visual field loss (CFL) adopt various strategies to complete activities of daily living (ADL). Using objective movement analysis, we compared how three ADLs were completed by people with CFL compared with age-matched, visually healthy individuals. METHODS: Fourteen participants with CFL (age 81 ± 10 years) and 10 age-matched, visually healthy (age 75 ± 5 years) participated. Three ADLs were assessed: pick up food from a plate, pour liquid from a bottle, and insert a key in a lock. Participants with CFL completed each ADL habitually (as they would in their home). Data were compared with visually healthy participants who were asked to complete the tasks as they would normally, but under specified experimental conditions. Movement kinematics were compared using three-dimension motion analysis (Vicon). Visual functions (distance and near acuities, contrast sensitivity, visual fields) were recorded. RESULTS: All CFL participants were able to complete each ADL. However, participants with CFL demonstrated significantly (P < 0.05) longer overall movement times, shorter minimum viewing distance, and, for two of the three ADL tasks, needed more online corrections in the latter part of the movement. CONCLUSIONS: Results indicate that, despite the adoption of various habitual strategies, participants with CFL still do not perform common daily living tasks as efficiently as healthy subjects. Although indices suggesting feed-forward planning are similar, they made more movement corrections and increased time for the latter portion of the action, indicating a more cautious/uncertain approach. Various kinematic indices correlated significantly to visual function parameters including visual acuity and midperipheral visual field loss.


Asunto(s)
Actividades Cotidianas , Escotoma/fisiopatología , Visión Binocular/fisiología , Agudeza Visual , Campos Visuales/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Escotoma/rehabilitación , Análisis y Desempeño de Tareas
7.
Zhonghua Yan Ke Za Zhi ; 51(7): 552-6, 2015 Jul.
Artículo en Chino | MEDLINE | ID: mdl-26310260

RESUMEN

In clinical practice, maculopathy and neurological eye disorders often cause visual field defects. Once the defects are formed, treatment and rehabilitation are confronted with the bottleneck due to irreversibility. With the transformation of medical patterns and people's higher needs for rehabilitation, new approaches to visual training for these diseases with visual field defects are emerging. Currently, visual rehabilitation training for patients with visual field defects focuses on two directions: central visual field defects and hemianopia / peripheral visual field defects. Patients' fine vision is mainly affected by central visual field defects, the rehabilitation training for which can be divided into eccentric viewing training, eye movement training and perceptual learning training. Patients' visual exploration, orientation, walking and reading are largely influenced by hemianopia and peripheral visual field defects, the rehabilitation training for which can be separated into visual restoration strategy and eye movement compensatory strategy.


Asunto(s)
Educación del Paciente como Asunto , Trastornos de la Visión/rehabilitación , Movimientos Oculares , Hemianopsia/rehabilitación , Humanos , Lectura , Escotoma/rehabilitación , Campos Visuales , Percepción Visual/fisiología , Caminata
8.
Ophthalmic Physiol Opt ; 34(4): 427-37, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24735182

RESUMEN

PURPOSE: The global prevalence of age-related macular degeneration and associated central vision loss is rising. Central vision loss hinders the performance of many activities of daily living. Adaptive strategies such as eccentric viewing and steady eye strategy may be used to compensate for central vision loss. In order to establish the potential of these rehabilitation strategies, this systematic review evaluates current literature regarding the effectiveness of eccentric viewing and steady eye strategy training in people with central vision loss. RESULTS: The search strategies identified 2605 publications, 36 of which met the inclusion criteria for the review, but only three of which were randomised controlled trials. This literature shows that eccentric viewing and steady eye strategy training can improve near visual acuity, reading speed, and performance of activities of daily living in people with central vision loss. However, there was insufficient literature to establish a relationship between training and distance visual acuity or quality of life. There is no conclusive evidence to show that a particular model of eccentric viewing training is superior to another, little clear evidence of a relationship between participant characteristics and training outcomes and no data regarding the cost effectiveness of training. CONCLUSION: This report highlights the need for further robust research to establish the true potential and cost effectiveness of eccentric viewing and steady eye strategy training as a rehabilitation strategy for individuals with central vision loss.


Asunto(s)
Fijación Ocular , Degeneración Macular/rehabilitación , Escotoma/rehabilitación , Campos Visuales , Actividades Cotidianas , Humanos , Calidad de Vida
9.
Can J Ophthalmol ; 48(5): 420-6, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24093190

RESUMEN

OBJECTIVE: To investigate the rehabilitative approach in patients with ring scotoma. A central scotoma is characteristic for patients with age-related macular degeneration (AMD). Sometimes patients with AMD maintain a residual central vision area within the scotoma (ring scotoma). DESIGN: Prospective, nonrandomized case series. PARTICIPANTS: Twenty-four patients with AMD. METHODS: A formal low-vision assessment was performed for all study patients. The assessment included best corrected visual acuity (BCVA), contrast sensitivity, reading speed, and microperimetry. All patients were provided a low-vision assessment to satisfy patients' needs. Devices were prescribed accordingly. RESULTS: The BCVA found was 0.4 logMAR (SD 0.1). All had central and stable fixation. Residual central retinal area size and sensitivity measured 2.4° (SD 0.8) and 3.1 dB (SD 0.8), respectively. Twenty patients achieved better vision with optical magnification in the eye with ring scotoma. Mean reading speed achieved was 50.2 words/min (SD 20.9). A linear correlation was found for reading speed with both central area sensitivity (r² = 0.5, p < 0.05) and contrast sensitivity (r² = 0.3, p < 0.05). CONCLUSIONS: In patients with AMD with ring scotoma, moderate amounts of magnification seem to provide satisfactory rehabilitation outcomes. Central retinal spared area sensitivity may predict reading speed outcomes, whereas residual central area size is likely to be useful in determining magnification.


Asunto(s)
Degeneración Macular/rehabilitación , Oftalmología/métodos , Escotoma/rehabilitación , Baja Visión/rehabilitación , Actividades Cotidianas , Anciano de 80 o más Años , Sensibilidad de Contraste/fisiología , Femenino , Fijación Ocular/fisiología , Humanos , Degeneración Macular/fisiopatología , Masculino , Estudios Prospectivos , Lectura , Retina/fisiopatología , Escotoma/fisiopatología , Umbral Sensorial , Baja Visión/fisiopatología , Agudeza Visual/fisiología , Pruebas del Campo Visual , Campos Visuales/fisiología
10.
Can J Ophthalmol ; 48(5): 431-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24093192

RESUMEN

OBJECTIVE: To evaluate changes in patient's visual performance after rehabilitation training with 2 different biofeedback training programs offered by the MP-1 microperimeter. Spontaneous retinal location of preferred retinal loci (PRLs) and fixation stability are not always optimal for best visual performances. MP-1 microperimeter biofeedback techniques have been suggested as modalities for training for better fixation stability and to find a better location of the new PRL in a more useful area of the retina in nonoptimal cases. The MP-1 microperimeter offers different biofeedback strategies, such as acoustic biofeedback and structured light stimulus plus acoustic biofeedback. DESIGN: Retrospective study. PARTICIPANTS: Thirty subjects affected by age-related macular degeneration with absolute central scotoma. METHODS: A standard protocol of examination before and after visual rehabilitation training was performed on all study subjects. Assessment included demographics data, visual acuity, fixation stability, retinal sensitivity, and reading speed. Rehabilitation training was performed with standard and structured stimulus biofeedback. The whole sample was divided into 2 groups of 15 patients attending the 2 different stimulation training biofeedback. RESULTS: Mean reading speed was found to be significantly increased for both groups (p < 0.05 and p < 0.01). Also, a statistically significant improvement of fixation stability was registered for both groups (p < 0.01). Only patients trained with the flickering pattern biofeedback stimulation increased retinal sensitivity (p < 0.01). CONCLUSIONS: Both regular biofeedback and flickering pattern biofeedback training seem to improve visual functions. More benefits seem to be accrued, however, with flickering pattern biofeedback training.


Asunto(s)
Biorretroalimentación Psicológica/métodos , Atrofia Geográfica/rehabilitación , Escotoma/rehabilitación , Baja Visión/rehabilitación , Actividades Cotidianas , Anciano , Femenino , Fijación Ocular/fisiología , Atrofia Geográfica/fisiopatología , Humanos , Masculino , Lectura , Retina/fisiopatología , Estudios Retrospectivos , Escotoma/fisiopatología , Baja Visión/fisiopatología , Agudeza Visual/fisiología , Pruebas del Campo Visual/métodos , Campos Visuales/fisiología
11.
Can J Ophthalmol ; 48(5): 438-42, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24093193

RESUMEN

OBJECTIVE: To evaluate the efficacy of the MP-1 microperimeter (Nidek Technologies Srl, Padova, Italy) and Visual Pathfinder (LACE Inc) in improving visual function of patients with myopic maculopathy. DESIGN: Prospective, nonrandomized, interventional case series. PARTICIPANTS: Seventeen patients (34 eyes) between 36 and 58 years of age with myopic maculopathy and central retinal scotomas. METHODS: After a complete eye examination, all patients underwent 10 training sessions with MP-1 biofeedback (7 minutes) and Visual Pathfinder (3 minutes) for each eye once a week. Statistical analysis was performed with Student t test. The p values less than 0.05 were considered statistically significant. RESULTS: The mean best corrected visual acuity increased from 0.64 ± 0.22 to 0.38 ± 0.20 logMAR at the end of follow-up (p = 0.03); visual-evoked potential P100 amplitude increased from 3.54 ± 1.90 to 6.64 ± 2.91 µV at the end of follow-up (p = 0.04); average retinal sensitivity, calculated in the 12 degrees of the central retina, increased from 6.6 ± 2.6 to 14.6 ± 3.6 dB (p = 0.03). Fixation behaviour in the 2 degrees of the central retina increased from 45% ± 17% to 75% ± 23% (p = 0.04). The bivariate contour ellipse area (95%) increased from 10.34 ± 3.11 to 7.64 ± 2.71 square degrees (p = 0.04). CONCLUSIONS: The combination of acoustic biofeedback training with MP-1 and Visual Pathfinder offers a reasonable improvement of visual function in patients with myopic maculopathy. This method might be considered as a rehabilitative strategy as a "therapeutic option" in these patients for whom most treatments usually do not work.


Asunto(s)
Biorretroalimentación Psicológica/métodos , Potenciales Evocados Visuales/fisiología , Miopía Degenerativa/rehabilitación , Enfermedades de la Retina/rehabilitación , Escotoma/rehabilitación , Agudeza Visual/fisiología , Pruebas del Campo Visual/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miopía Degenerativa/complicaciones , Miopía Degenerativa/fisiopatología , Estudios Prospectivos , Lectura , Retina/fisiopatología , Enfermedades de la Retina/etiología , Enfermedades de la Retina/fisiopatología , Escotoma/etiología , Escotoma/fisiopatología , Resultado del Tratamiento
12.
Optom Vis Sci ; 89(9): 1374-84, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22885784

RESUMEN

PURPOSE: Age-related macular degeneration is the leading cause of vision loss among Americans aged >65 years. Currently, no effective treatment can reverse the central vision loss associated with most age-related macular degeneration. Digital image-processing techniques have been developed to improve image visibility for peripheral vision; however, both the selection and efficacy of such methods are limited. Progress has been difficult for two reasons: the exact nature of image enhancement that might benefit peripheral vision is not well understood, and efficient methods for testing such techniques have been elusive. The current study aims to develop both an effective image enhancement technique for peripheral vision and an efficient means for validating the technique. METHODS: We used a novel contour-detection algorithm to locate shape-defining edges in images based on natural-image statistics. We then enhanced the scene by locally boosting the luminance contrast along such contours. Using a gaze-contingent display, we simulated central visual field loss in normally sighted young (aged 18-30 years) and older adults (aged 58-88 years). Visual search performance was measured as a function of contour enhancement strength ["original" (unenhanced), "medium," and "high"]. For preference task, a separate group of subjects judged which image in a pair "would lead to better search performance." RESULTS: We found that although contour enhancement had no significant effect on search time and accuracy in young adults, Medium enhancement resulted in significantly shorter search time in older adults (about 13% reduction relative to original). Both age-groups preferred images with Medium enhancement over original (2-7 times). Furthermore, across age-groups, image content types, and enhancement strengths, there was a robust correlation between preference and performance. CONCLUSIONS: Our findings demonstrate a beneficial role of contour enhancement in peripheral vision for older adults. Our findings further suggest that task-specific preference judgments can be an efficient surrogate for performance testing.


Asunto(s)
Algoritmos , Sensibilidad de Contraste/fisiología , Percepción de Forma/fisiología , Aumento de la Imagen/métodos , Iluminación/métodos , Reconocimiento Visual de Modelos/fisiología , Escotoma/rehabilitación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escotoma/fisiopatología , Campos Visuales , Adulto Joven
13.
Optom Vis Sci ; 89(9): 1282-7, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22885786

RESUMEN

PURPOSE: Past research has not fully ascertained the extent to which people with glaucoma have difficulties with reading. This study measures change in reading speed when letter contrast is reduced, to test the hypothesis that patients with glaucoma are more sensitive to letter contrast than age-similar visually healthy people. METHODS: Fifty-three patients with glaucoma [mean age: 66 years (standard deviation: 9)] with bilateral visual field (VF) defects and 40 age-similar visually healthy control subjects [mean age: 69 (standard deviation: 8) years] had reading speeds measured using sets of fixed size, non-scrolling texts on a computer setup that incorporated an eye tracking device. All participants had visual acuity ≥6/9, and they underwent standard tests of visual function including Humphrey 24-2 and 10-2 VFs. Potential non-visual confounders were also tested, including cognitive ability (Middlesex Elderly Assessment of Mental Status Test) and general reading ability. Individual average raw reading speeds were calculated from 8 trials (different passages of text) at both 100% and 20% letter contrast. RESULTS: Patients had an average 24-2 VF MD of -6.5 (range: 0.7 to -17.3) dB in the better eye. The overall median reduction in reading speed due to decreasing the contrast of the text in the patients was 20%, but with considerable between-individual variation (interquartile range, 8%-44%). This reduction was significantly greater (p = 0.01) than the controls [median: 11% (interquartile range, 6%-17%)]. Patients and controls had similar average performance on Middlesex Elderly Assessment of Mental Status Test (p = 0.71), a modified Burt Reading ability test (p = 0.33), and a computer-based lexical decision task (p = 0.53) and had similar self-reported day-to-day reading frequency (p = 0.12). CONCLUSIONS: Average reduction in reading speed caused by a difference in letter contrast between 100% and 20% is significantly more apparent in patients with glaucoma when compared with visually healthy people with a similar age and similar cognitive/reading ability.


Asunto(s)
Sensibilidad de Contraste/fisiología , Glaucoma de Ángulo Abierto/rehabilitación , Glaucoma de Baja Tensión/rehabilitación , Lectura , Escotoma/rehabilitación , Campos Visuales/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Glaucoma de Ángulo Abierto/complicaciones , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Presión Intraocular , Glaucoma de Baja Tensión/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Escotoma/etiología , Escotoma/fisiopatología , Pruebas del Campo Visual
14.
Optom Vis Sci ; 89(9): 1395-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22863789

RESUMEN

PURPOSE: To assess whether age-related macular degeneration (AMD) patients are aware of binocular central visual field defects. METHODS: One hundred fifty-three consecutive AMD patients in their initial low-vision rehabilitation evaluation were immediately asked at the beginning of their visit (1) whether they were able to see any blind spots or defects in their field of vision and (2) whether they had any evidence or experiences that led them to believe that they had defects in their field of vision. They then had their vision assessed by binocular central visual field testing using the California Central Visual Field Test, binocular reading performance evaluated using the Smith-Kettlewell Reading Test (SK Read) and MN Read charts, and visual acuity measured using the ETDRS chart at 1 meter. Mean diameters of the scotomas with borders near fixation were noted. RESULTS: Visual acuity median was 20/253 (range 20/40 to hand movements). Binocular scotomas were present in 88% of patients (66% had dense scotoma). Of patients with binocular scotomas, 56% were totally unaware of their presence, even with dense scotomas measuring up to 30° in diameter; 1.5% could fleetingly see a defect in their visual field on waking; and 44% related experiences of things "disappearing" on them. The median and range of scotoma diameters for those unaware vs. those with some awareness of their scotomas were comparable. There was no significant relationship of awareness of the scotoma with age, acuity, scotoma size, density, or duration of onset. Awareness of scotoma was associated with fewer errors on the SK Read (p < 0.01). CONCLUSIONS: Low vision clinicians cannot depend on patients to report the presence of significant scotomas; thus, appropriate testing must be performed. Presence of scotomas decreased reading accuracy, but some awareness of the scotomas had a tendency to improve accuracy. The value of rehabilitation programs aimed at increasing patient awareness of their scotomas may be supported by this evidence.


Asunto(s)
Concienciación , Degeneración Macular/complicaciones , Degeneración Macular/psicología , Escotoma/psicología , Visión Binocular/fisiología , Campos Visuales/fisiología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Degeneración Macular/fisiopatología , Masculino , Persona de Mediana Edad , Escotoma/etiología , Escotoma/rehabilitación , Agudeza Visual , Pruebas del Campo Visual
15.
Optom Vis Sci ; 89(9): 1417-23, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22842306

RESUMEN

PURPOSE: To investigate the effect of eccentric refractive correction and full aberration correction on both high- and low-contrast grating resolution at the preferred retinal locus (PRL) of a single low-vision subject with a long-standing central scotoma. METHODS: The subject was a 68-year-old women with bilateral absolute central scotoma due to Stargardt disease. She developed a single PRL located 25° nasally of the damaged macula in her left eye, this being the better of the two eyes. High- (100%) and low-contrast (25 and 10%) grating resolution acuity was evaluated using four different correction conditions. The first two corrections were solely refractive error corrections, namely, habitual spectacle correction and full spherocylindrical correction. The latter two corrections were two versions of adaptive optics corrections of all aberrations, namely, habitual spectacle correction with aberration correction and full spherocylindrical refractive correction with aberration correction. RESULTS: The mean high-contrast (100%) resolution acuity with her habitual correction was 1.06 logMAR, which improved to 1.00 logMAR with full spherocylindrical correction. Under the same conditions, low-contrast (25%) acuity improved from 1.30 to 1.14 logMAR. With adaptive optics aberration correction, the high-contrast resolution acuities improved to 0.89/0.92 logMAR and the low-contrast acuities improved to 1.04/1.06 logMAR under both correction modalities. The low-contrast (10%) resolution acuity was 1.34 logMAR with adaptive optics aberration correction; however, with purely refractive error corrections, she was unable to identify the orientation of the gratings. CONCLUSIONS: Correction of all aberrations using adaptive optics improves both high- and low-contrast resolution acuity at the PRL of a single low-vision subject with long-standing absolute central scotoma.


Asunto(s)
Anteojos , Retina/fisiopatología , Escotoma/rehabilitación , Agudeza Visual/fisiología , Anciano , Diseño de Equipo , Femenino , Humanos , Oftalmoscopía , Estimulación Luminosa , Escotoma/fisiopatología
16.
Korean J Ophthalmol ; 25(6): 409-16, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22131778

RESUMEN

PURPOSE: The definition of eccentric viewing (EV) is using non-foveal preferred retinal loci (PRL) for viewing. The purpose of the present study was to investigate the clinical effect of EV training for low vision rehabilitation in patients with central scotomas. METHODS: The direction of EV was monitored in 30 low vision patients with central scotomas by moving the patient's view. The PRL was found by using a direct ophthalmoscope and retinal camera; the preserved visual field was identified using a kinetic visual field analyzer. The relationships between EV, PRL, and visual field were evaluated. The patients and their guardians were educated regarding EV. After 2 weeks of self-training, maintenance of EV was checked and changes in best-corrected visual acuity (BCVA), reading speed, and satisfaction questionnaire were evaluated. RESULTS: A relationship between EV, PRL, and visual field was in accordance in half of the patients. There were no significant differences in demographics and basic visual characteristics in patients where the relationship was not in accordance. EV was maintained in two-thirds of the patients, but there were no significant differences in demographics and basic visual characteristics in patients who discontinued EV. There were no significant improvements in BCVA; however, reading speed and the satisfaction scores increased significantly with EV. CONCLUSIONS: The direction of EV was effectively detected by convenient access using an inexpensive method. Functional vision and satisfaction significantly improved following EV training. EV training can be used as an effective method for low vision rehabilitation in patients with central scotomas.


Asunto(s)
Rehabilitación/métodos , Escotoma/rehabilitación , Baja Visión/rehabilitación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Lectura , Escotoma/fisiopatología , Encuestas y Cuestionarios , Baja Visión/fisiopatología , Agudeza Visual/fisiología , Adulto Joven
17.
J Rehabil Res Dev ; 48(9): 1101-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22234714

RESUMEN

To investigate the relationship between depression and quantitative measures of visual function, we recruited 18 subjects with central scotomas from macular degeneration who were enrolled in a reading rehabilitation program. Psychological batteries and reading assessments were administered prior to rehabilitation; reading assessments and a measure of adaptation to vision loss were administered following rehabilitation. We investigated relationships between reported levels of depressive symptoms and reading and adaptation outcome measures by using Pearson product moment correlation analysis. Results revealed a significant relationship between depression levels and reading acuity difference scores (r(16) = 0.54, p = 0.02) and changes in adaptation to vision loss levels (r(16) = 0.62, p = 0.01), suggesting that those who reported greater depressive symptoms did not respond as well functionally to reading rehabilitation but reported greater improvement in levels of adaptation to vision loss following rehabilitation. Future research should focus on defining standard methods to assess and remediate depression as part of the rehabilitation process.


Asunto(s)
Depresión/complicaciones , Degeneración Macular/complicaciones , Lectura , Escotoma/etiología , Escotoma/rehabilitación , Personas con Daño Visual/rehabilitación , Actividades Cotidianas , Adaptación Psicológica , Anciano , Anciano de 80 o más Años , Depresión/psicología , Evaluación de la Discapacidad , Femenino , Humanos , Degeneración Macular/psicología , Degeneración Macular/rehabilitación , Masculino , Persona de Mediana Edad , Percepción , Escalas de Valoración Psiquiátrica , Escotoma/psicología , Perfil de Impacto de Enfermedad , Encuestas y Cuestionarios , Resultado del Tratamiento , Pruebas de Visión
18.
Klin Monbl Augenheilkd ; 226(11): 897-907, 2009 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-19916150

RESUMEN

This review considers diseases of the visual pathways at different levels, their consequences for relevant everyday functions and their rehabilitation. Infrachiasmatic lesions are mostly associated with central or ring scotomas causing reading problems. The use of an eccentric fixation locus in combination with text magnification often allows the patient to maintain reading ability. Chiasmatic lesions can cause orientation disability by bitemporal hemianopia and reading problems by slide phenomena along the vertical midline. Suprachiasmatic lesions lead to homonymous visual field defects. Regarding the hemianopic orientation disorder, there are two different training approaches, which have been discussed controversially: restitution of the visual field by visual stimulation versus compensation by explorative eye movements towards the hemianopic side. Previously described positive effects of exploration training were not entirely convincing due to the lack of control groups. A new randomised and controlled study has proved the effectiveness of exploration training and showed that the patients apply the improved exploration strategy to everyday life. In the control group, which received a visual field stimulation training--a potential restitution training--neither exploration nor visual fields changed. The hemianopic reading disorder depends on the distance of the field defect from the centre, i. e., the size of the reading visual field, the side of the field defect in regard to the reading direction and the presence of spontaneous adaptive strategies, such as eccentric fixation or predictive saccades. Specific reading training can be helpful. Cerebral visual impairments with visual field defects are often associated with disorders of information processing in higher cortical areas. These complex disorders usually require an interdisciplinary rehabilitation. Specific examination methods to assess functions of everyday relevance and their use as a basis for rehabilitation measures are discussed. Visual rehabilitation can be very successful in many cases and improves the patients' quality of life. One should expect that the demand for neuro-ophthalmological rehabilitation will increase, because the survival rate after severe cerebral lesions and the general lifespan are rising.


Asunto(s)
Ceguera Cortical/rehabilitación , Hemianopsia/rehabilitación , Trastornos de la Percepción/rehabilitación , Escotoma/rehabilitación , Vías Visuales/fisiopatología , Percepción Visual/fisiología , Recursos Audiovisuales , Ceguera Cortical/fisiopatología , Evaluación de la Discapacidad , Hemianopsia/fisiopatología , Quiasma Óptico/fisiopatología , Ensayos Clínicos Controlados Aleatorios como Asunto , Lectura , Escotoma/fisiopatología , Corteza Visual/fisiopatología , Campos Visuales/fisiología
19.
J Vis ; 8(5): 6.1-18, 2008 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-18842077

RESUMEN

Forcing normal-sighted participants to use a distinct parafoveal retinal location for reading, we studied which part of the visual field is best suited to take over functions of the fovea during early stages of macular degeneration (MD). A region to the right of fixation lead to best reading performance and most natural gaze behavior, whereas reading performance was severely impaired when a region to the left or below fixation had to be used. An analysis of the underlying oculomotor behavior revealed that practice effects were accompanied by a larger number of saccades in text direction and decreased fixation durations, whereas no adjustment of saccade amplitudes was observed. We provide an explanation for the observed performance differences at different retinal locations based on the interplay of attention and eye movements. Our findings have important implications for the development of training methods for MD patients targeted at reading, suggesting that it would be beneficial for MD patients to use a region to the right of their central scotoma.


Asunto(s)
Adaptación Fisiológica/fisiología , Fóvea Central/fisiología , Lectura , Movimientos Sacádicos/fisiología , Campos Visuales/fisiología , Adulto , Algoritmos , Atención/fisiología , Femenino , Fijación Ocular/fisiología , Humanos , Degeneración Macular/fisiopatología , Degeneración Macular/rehabilitación , Masculino , Modelos Neurológicos , Escotoma/fisiopatología , Escotoma/rehabilitación , Agudeza Visual/fisiología
20.
BMC Ophthalmol ; 6: 35, 2006 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-17123448

RESUMEN

BACKGROUND: Reading with a central scotoma involves the use of preferred retinal loci (PRLs) that enable both letter resolution and global viewing of word. Spontaneously developed PRLs however often privilege spatial resolution and, as a result, visual span is commonly limited by the position of the scotoma. In this study we designed and performed the pilot trial of a training procedure aimed at modifying oculomotor behavior in subjects with central field loss. We use an additional fixation point which, when combined with the initial PRL, allows the fulfillment of both letter resolution and global viewing of words. METHODS: The training procedure comprises ten training sessions conducted with the scanning laser ophthalmoscope (SLO). Subjects have to read single letters and isolated words varying in length, by combining the use of their initial PRL with the one of an examiner's selected trained retinal locus (TRL). We enrolled five subjects to test for the feasibility of the training technique. They showed stable maculopathy and persisting major reading difficulties despite previous orthoptic rehabilitation. We evaluated ETDRS visual acuity, threshold character size for single letters and isolated words, accuracy for paragraphed text reading and reading strategies before, immediately after SLO training, and three months later. RESULTS: Training the use of multiple PRLs in patients with central field loss is feasible and contributes to adapt oculomotor strategies during reading related tasks. Immediately after SLO training subjects used in combination with their initial PRL the examiner's selected TRL and other newly self-selected PRLs. Training gains were also reflected in ETDRS acuity, threshold character size for words of different lengths and in paragraphed text reading. Interestingly, subjects benefited variously from the training procedure and gains were retained differently as a function of word length. CONCLUSION: We designed a new procedure for training patients with central field loss using scanning laser ophthalmoscopy. Our initial results on the acquisition of newly self-selected PRLs and the development of new oculomotor behaviors suggest that the procedure aiming primarily at developing an examiner's selected TRL might have initiated a more global functional adaptation process.


Asunto(s)
Mácula Lútea , Músculos Oculomotores/fisiopatología , Oftalmoscopía , Lectura , Enfermedades de la Retina/complicaciones , Escotoma/fisiopatología , Escotoma/rehabilitación , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Humanos , Rayos Láser , Proyectos Piloto , Escotoma/etiología
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