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We suggest a low-vision reading aid based on user-customized text presented on a head-mounted display (HMD), and make an initial comparison to optical aids in participants with age-related macular degeneration (AMD). Biomimetic scrolling, a novel method of text presentation which mimics the natural movements of the eye while reading, was previously invented: while the user maintains a steady gaze, text is scrolled horizontally across the display in a series of pauses and steps that resemble the natural fixations and saccades of reading. This method, along with rapid serial visual presentation, continuous scrolling, and static text, was presented on smart glasses to 23 participants with macular disease. Reading speed and subjective preference of the smart glasses was compared to reading text printed on paper using the participants’ habitual optical reading aid. Reading using smart glasses, the mean (±standard error) maximum reading speed was 122 ± 15 words per minute (wpm), compared to 74 ± 9 wpm using each participants’ habitual optical magnifier. This is a statistically significant difference as confirmed by a paired-sample t-test, t(17) = –4.61, p

The findings of this study can be used in the selection of the preferred retinal locus to establish better rehabilitation services such as eccentric viewing training for patients with age-related macular degeneration.The aim of this study was to determine the characteristics of the preferred retinal locus in native Persian-speaking patients with age-related macular degeneration.In this non-interventional case series, all patients with a diagnosis of age-related macular degeneration referred to the Retina Clinic of the Rassoul Akram Hospital, Tehran, Iran, were evaluated. The fixation characteristics were evaluated monocularly using the MP1 microperimeter (Nidek Technologies, Padua, Italy). Optical coherence tomography was used to determine the location of the central fovea. The images were overlaid and the preferred retinal locus-fovea distance was measured using Image J software.Fifty-one eyes of 35 patients with a mean age of 73.8 ± 7.7-years were evaluated in this study. Inferior-field, left-field, central-field, right-field, and superior-field preferred retinal locus were detected in 49 per cent, 33.3 per cent, 7.8 per cent, 5.9 per cent, and 3.9 per cent of the subjects, respectively. Fixation was stable in 70.6 per cent, relatively unstable in 15.7 per cent, and unstable in 13.7 per cent of the participants. Significant differences were not found in the mean values of logMAR visual acuity between different fields of the preferred retinal locus after Bonferroni correction (p = 0.031). Analysis of co-variance showed no significant difference in mean sensitivity values between different locations of the preferred retinal locus (p = 0.07). The mean preferred retinal locus-fovea distance was not significantly different between different fields of the preferred retinal locus (p = 0.063).Native Persian-speaking patients with central scotoma secondary to age-related macular degeneration place their self-selected preferred retinal locus most frequently in the inferior and left visual field, which would result in scotoma displacement to the superior and right visual field. Fixation stability was statistically similar in different locations of preferred retinal locus, but it improved with decreasing the preferred retinal locus-fovea distance.

Objective : To examine the effects of the eccentric viewing training software on reading and Activities of Daily Living(ADL) for individuals with central scotomas in Korea. Methods : A single-subject A-B-A research design for two low-vision individuals with central scotomas was used to examine the effects. The research was conducted over 14 sessions, which included three sessions during a pre-training baseline period (A), eight sessions during an intervention period to apply eccentric viewing training software on Korean character stimulation (B), and three sessions in a post-training baseline period (A). To measure reading and ADL, participants were assessed for their reading speed, Canadian Occupational Performance Measure(COPM), and Assessment of Motor and Process Skills(AMPS). Results : An Analysis of the data showed that the participants’ reading speed increased compared to their pre-training baseline scores, showing the highest level of increase in the first two to three sessions of training. The participants improved their performance in the reading-related activities, although a comparison of their overall ADL function pre-training and post-training showed no change. Conclusion : These findings suggest that the eccentric viewing training based on specific language characters, Korean, is an effective intervention method for improvement in the reading skills of individuals with central scotomas.

SIGNIFICANCE This study explores whether eccentric viewing training (EVT) changes the properties of the retinal area used for fixation in subjects with bilateral macular disease. The data presented demonstrate the feasibility of conducting a randomized controlled trial on EVT. PURPOSE Patients with bilateral central scotomas adopt other retinal area(s) called preferred retinal locus to substitute the blind fovea. EVT is offered with the goal to improve functional vision by learning how to identify and use a more useful retinal area for fixation-a trained retinal locus-and/or to improve fixation stability with their existing preferred retinal locus. An observational study was conducted to determine whether patients change and adopt a new trained retinal locus location and/or if fixation stability improves after EVT. METHODS Seventy-six patients with bilateral central scotomas received EVT from an experienced rehabilitation therapist. Retinal locations for repeated fixations and sizes of central scotomas of the better eye were recorded before and after EVT with a scanning laser ophthalmoscope. The position and area of the 95% confidence bivariate ellipse that defines the retinal area in which 95% of fixations occur were analyzed. RESULTS We observed no significant difference between the size of the area of the fitted ellipses before (mean [SD], 26.4° [19.7°]) and after (mean [SD], 24.8° [20.9°]) EVT (P = .54). However, we observed a shift in the preferred retinal locus location after EVT (P < .0001). The mean (SD) shift in the position of the center of fixation after EVT was 7.5° (5.2°; range, 0.45 to 23°). This mean difference was larger than would be expected from average within-subject fixation stability. CONCLUSIONS The location of the retinal area used for fixation changes after EVT. Fixation stability does not change after EVT. These preliminary data are yet to be confirmed with the use of a control group.

Background: Eccentric viewing in macular disease has been described for half a century. However, a clear definition of eccentric viewing and preferred retinal locus (PRL) does not exist. Here, we determine how the PRL in macular disease is defined by researchers active in this field and, based on the responses received, propose a standardized definition of the preferred retinal locus.Method: A literature review of articles describing the PRL or eccentric viewing was performed. The first and senior authors of all identified publications were contacted and were asked to define the preferred retinal locus. Themes of responses were identified using inductive qualitative research techniques.Results: Frequently recurring themes related to the definition of the PRL included 1) it is a retinal area used for fixation, 2) it is task specific, 3) more than one PRL can be used, 4) it is a well-defined region of retina, and 5) the same PRL is used on repeated testing.Conclusion: Based on the responses received, a consensus definition of the PRL is proposed. It is suggested that researchers define the PRL carefully in experimental reports and an instrument that images the retina is used to define the location of the PRL. RETINA 31:2109-2114, 2011

Macular degeneration has a severe impact on a person's ability to perform activities of daily living. This study investigated the impact of in-home training in eccentric viewing on near acuity and performance of activities of daily living. The results suggest that eccentric viewing can ameliorate the impact of the loss of vision that is due to macular degeneration.

Purpose. Many parameters of visual performance (e.g., contrast sensitivity) are compromised under glaring light conditions. Recent data indicate that macular pigment (MP) is strongly related to improvements in glare disability and photostress recovery based on a filtering mechanism. In this study, we assessed the causality of this relation by supplementing lutein and zeaxanthin for 6 months while measuring MP, glare disability, and photostress recovery. Methods. Forty healthy subjects (mean age 23.9) participated in the study. Subjects were followed for 6 months and assessed at baseline, 1, 2, 4, and 6 months. Spatial density profiles of MP were measured using heterochromatic flicker photometry. Disability glare was measured using a 1 degree-diameter circular grating surrounded by a broadband glare source (a xenon-white annulus). The intensity of the annulus (11 degree inner and 12 degree outer diameters) was adjusted by the subject until the grating target was no longer seen. For the photostress recovery experiment, the time required to detect a 1 degree-diameter grating stimulus after a 5-s exposure to a 2.5 W/cm 2 , 5 degree-diameter disk was recorded. Subjects were tested under central viewing and eccentric viewing (10 degree temporal retina) conditions. Results. At the baseline time point, MP optical density (OD) at 30 eccentricity ranged from 0.08 to 1.04, and was strongly correlated with improved visual performance in the two glare tasks. After 6 months of lutein (L) and zeaxanthin (Z) supplementation, average MPOD (at 30 eccentricity) had increased from 0.41 to 0.57, and was shown to significantly reduce the deleterious effects of glare for both the visual performance tasks assessed. Conclusions. MP is strongly related to improvements in glare disability and photostress recovery in a manner strongly consistent with its spectral absorption and spatial profile. Four to 6 months of 12 mg daily L Z supplementation significantly increases MPOD and improves visual performance in glare for most subjects. (Optom Vis Sci 2008;85:82–88)

Loss of macular vision has been shown to impact on performance of activities of daily living. The aim of this study was to report a clinical evaluation of client perceptions and results of a random control trial of eccentric viewing and magnification interventions on the performance of activities of daily living (ADL). Client perceptions were obtained from a retrospective analysis of post training evaluation questionnaires. A random control design was used to compare the impact of three interventions (eccentric viewing, magnification and combined intervention) on the performance of daily function. Data was analysed using between and within group one-way analysis of variance. Questionnaire data indicated clients perceived eccentric viewing had assisted performance of ADL. Results of the random control study in relation to the dependant variable ADL demonstrated that intervention significantly improved performance. The eccentric viewing intervention demonstrated greater improvement in dynamic activities, e.g. shopping. The magnification intervention demonstrated the greatest improvement in high acuity activities, e.g. coin identification. Eccentric viewing and magnification generally improve the performance of ADL, however each is suited to different types of activity.

Purpose: Patients with an absolute central scotoma, such as in age-related macular degeneration, need to use eccentric viewing for reading. In the present study, we investigated whether there are differences in reading performance between the superior and inferior retina. Methods: Twelve volunteers with normal vision, aged 25-58 years and able to maintain stable eccentric viewing, were studied in a scanning laser ophthalmoscope while reading a line of text, 6 degrees above or below a fixation line (series A). The text, properly magnified above threshold, was scrolled at a speed of 60 words/min. The number of words missed or incorrectly read in 1 min as well as words read when occasionally fixating the text was counted. In series B, a random letter text was superimposed upon the fixation line (i.e. at 6 degrees from the original line of text) to see whether this would disturb reading. In series C, the random letter text was moved away from the fixation line to a distance of 12 degrees from the original line of text. The entire programme was repeated in reverse order, and the mean value of the two series was used for calculations, which were carried out using Student's two-sided t-test. Results: In all series of experiments, the number of errors was significantly lower when using the superior retina compared with the inferior retina (A: p = 0.006, B: p = 0.042, C: p = 0.009). The addition of the random letter line of text at 6 or 12 degrees did not disturb reading performance significantly. There was no significant difference between the superior and inferior retina in terms of visual acuity. Conclusions: In eccentric viewing, reading performance was significantly better when using the superior retina compared with the inferior retina. A line of random letter text at a distance of 6 or 12 degrees from the original line of text did not disturb reading significantly. © 2007 The Authors Journal Compilation © 2007 Acta Ophthalmol Scand.

Purpose.: The detection of amblyopia in children relies on an accurate assessment of visual acuity. Visual deficits in anisometropic and strabismic amblyopia are different, but the influence of chart design, in particular position, and type of crowding features on visual acuity in the two types of amblyopia, is not clear. Certain aspects of amblyopic spatial vision are mimicked in healthy individuals by imposing increasing levels of blur and retinal eccentricity. We measured the effects of these conditions on visual acuity in healthy adults, with crowded and uncrowded vision tests. Methods.: Visual acuity was measured under conditions of blur (0–4 D) and eccentric viewing (0–5 degrees) using high-contrast optotypes derived from common children's acuity charts. Optotypes were presented in isolation, in commercially available crowded configurations, and in configurations with closer target-flanker separations than those currently available. Results.: Dioptric blur had similar degradative effects on crowded and isolated visual acuity (P > 0.05), whereas eccentric viewing resulted in a larger deterioration of visual acuity for crowded tests (E 2 of 0.86–1.06) than for isolated optotypes (E 2 of 1.57–1.72) (P < 0.05). Maximum crowding effects occurred for closer target-flanker separations than those currently used commercially. Conclusions.: In so far as blur and eccentric viewing mimic spatial acuity deficits in amblyopia, the results suggest that crowded tests might be of limited value in the detection of anisometropic amblyopia, but should be valuable in the detection of strabismic amblyopia. Crowding effects would be greater if flanking features were placed closer to the target than they currently are in commercially available charts.

Age-related macular degeneration (AMD) is the single most common cause of vision loss in people over the age of 50.1 Individuals with low vision caused by macular disease, experience severe difficulty with everyday tasks such as reading2 which has profound detrimental consequences for their quality of life.3 We have developed an app for the iPad (the MD_evReader) that aims to improve reading by enhancing the effectiveness of the eccentric viewing technique (EV) using dynamic text presentation (figure 1A). Eccentric viewing is a simple strategy adopted by individuals with AMD that involves using the relatively preserved peripheral region of their retina in order to see. A limiting factor of the EV technique is that it relies on the individual holding their gaze away from the focus of interest and suppressing the …

Purpose To quantify the effects of three vision rehabilitation training approaches on improvements in reading performance. Methods Thirty subjects with AMD participated in the training portion of the study. The median age of the subjects was 79 years (range, 54-89 years). The three training modules were: Visual Awareness and Eccentric Viewing (module 1), Control of Reading Eye Movements (module 2), and Reading Practice with Sequential Presentation of Lexical Information (module 3). Subjects were trained for 6 weekly sessions on each module, and the order of training was counterbalanced. All subjects underwent four assessments: at baseline and at three 6-week intervals. Reading performance was measured before and after each training module. A separate group of 6 subjects was randomly assigned to a control condition in which there was no training. These subjects underwent repeated assessments separated by 6 weeks. Results Reading speeds decreased by an average of 8.4 words per minute (wpm) after training on module 1, increased by 27.3 wpm after module 2, and decreased by 9.8 wpm after module 3. Only the increase in reading speed after module 2 was significantly different from zero. Sentence reading speeds for the control group, who had no reading rehabilitation intervention, was essentially unchanged over the 18 weeks (0.96 ± 1.3 wpm). Conclusions A training curriculum that concentrates on eye movement control increased reading speed in subjects with AMD. This finding does not suggest that the other rehabilitation modules have no value; it suggests that they are simply not the most effective for reading rehabilitation.

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.

Adaptation to eccentric viewing in subjects with a central scotoma remains poorly understood. The purpose of this study was to analyze the adaptation stages of oculomotor control to forced eccentric reading in normal subjects.Three normal adults (25.7 +/- 3.8 years of age) were trained to read full-page texts using a restricted 10 degrees x 7 degrees viewing window stabilized at 15 degrees eccentricity (lower visual field). Gaze position was recorded throughout the training period (1 hour per day for approximately 6 weeks).In the first sessions, eye movements appeared inappropriate for reading, mainly consisting of reflexive vertical (foveating) saccades. In early adaptation phases, both vertical saccade count and amplitude dramatically decreased. Horizontal saccade frequency increased in the first experimental sessions, then slowly decreased after 7 to 15 sessions. Amplitude of horizontal saccades increased with training. Gradually, accurate line jumps appeared, the proportion of progressive saccades increased, and the proportion of regressive saccades decreased. At the end of the learning process, eye movements mainly consisted of horizontal progressions, line jumps, and a few horizontal regressions.Two main adaptation phases were distinguished: a "faster" vertical process aimed at suppressing reflexive foveation and a "slower" restructuring of the horizontal eye movement pattern. The vertical phase consisted of a rapid reduction in the number of vertical saccades and a rapid but more progressive adjustment of remaining vertical saccades. The horizontal phase involved the amplitude adjustment of horizontal saccades (mainly progressions) to the text presented and the reduction of regressions required.

Low vision may affect a person's learning, daily functioning, and psychosocial status. Intervention in the form of vision rehabilitation has enabled many people to successfully meet and overcome the challenges posed by low vision. Part one of this two-part feature presented a four-phase, interdisciplinary model of low vision services that can be applied to any setting. This paper (part two) focuses on methods of assessing low vision, providing clinical services, and establishing an adaptive training and instructional program. The collaborative relationship between the patient/client, low vision physician (optometrist or ophthalmologist), and allied health professional (specifically, the occupational therapist) is described.

The influence of visual fixation position and stimulus size on the scalp-recorded "vertex positive peak" (VPP) evoked by images of faces was studied in three subjects. Responses were recorded, in turn, for line-drawn, frontal-view faces of approximately 8, 4, 2, and 1 deg length, fixated at the centre (bridge of the nose), and at points 1, 2, 3, and 4 deg to the left and right, and above and below, centre. The results showed that central fixation produced VPPs of similar, maximal amplitude for all face sizes. By comparison, "on-face" eccentric viewing yielded attenuated and delayed responses, and the degree of response attenuation as a function of eccentricity was directly related to the face size, with similar amplitude responses being evoked for corresponding fixation locations on each face. Very small or no VPPs were recorded for most "off-face" fixations. Similar results were observed for profile faces, except that the maximal VPP was recorded for fixations near the eyes and not in the centre of the head, and almost identical VPPs were evoked by a centrally fixated face presented with and without an adjacent face or object. These response properties, which correspond to the subjective perception of the facial stimuli, suggest that the VPP reflects brain mechanisms optimized to respond to single, fixated faces, irrespective both of facial image size and of the presence of neighbouring figures.

Oculomotor behaviour was investigated in 14 patients with central scotomas from age related macular degeneration (AMD) or Stargardt's disease. A scanning laser ophthalmoscope (SLO) was used to project letters and words onto the retina and to assess fixation behaviour. Five patients reported while deciphering letters that they needed to "move their eye" to prevent the image from vanishing. The observation of the SLO fundus images revealed that the gradual disappearance of the stimulus did not result from a transient projection of the word in the lesion. This prompted the authors to investigate, in an experimental setting, whether purposeful changes in fixation position could improve the perception of an eccentrically fixated text stimulus.Twenty normal subjects were asked to alternate fixation, every three to four seconds, between two vertically aligned dots, spaced 10 degrees apart, and to report any changes in the perception of a laterally located letter, 1.5 degrees in height, 7 degrees apart and equidistant between the two fixation spots.Nineteen subjects reported a transient refreshment of the letter image immediately after the realisation of a saccade. Improved perception lasted approximately a second. With persistent fixation, they noted a rapid fading effect that reduced letter recognition.These observations suggest that ocular instability during eccentric viewing can have a functional advantage, probably related to counteracting Troxler's phenomenon. In addition to alternating between PRLs, it appears that saccades related to fixation instability might be valuable and improve text perception in individuals with a central scotoma and eccentric fixation. This possibility should be taken into consideration when conducting visual rehabilitation procedures.

A study was conducted to determine the current Department of Veterans Affairs (VA) standard of practice for eccentric viewing (EV) training. EV training is the process of teaching patients to realign the visual image away from a diseased foveal/macular region onto healthier retina. Optometrists and Visual Skills Instructors at all VA blind rehabilitation centers (BRCs) and VICTORS (vision impairment centers to optimize remaining sight) programs were asked to rate preference for EV prescription criteria, evaluation, and training techniques. Responses were received from 70% of BRCs and 67% of VICTORS. The respondents reported that all programs include EV training. The average minutes of training per patient varied from 20 minutes to nearly 24 hours, with instructors within a single center varying by as much as two orders of magnitude. Routinely, 82% of optometrists prescribe EV training, yet no consensus was found among these practitioners as to the criteria for selecting the best EV area. The results of this survey reveal an inconsistent standard of practice across VA centers and demonstrate the need for prospective studies of the efficacy, effectiveness, and cost-effectiveness of EV training.

The development of a central scotoma, or decreased central vision, particularly in a person with a history of visual impairment, may severely interfere with an individual's ability to function visually. The nature of the impairment and current techniques for training an individual to use the peripheral retina are discussed.

Patients with macular dysfunction were given spectacle lenses with prism and a control group of similar patients were assessed without prism. About 60% of those without prisms learned to improve acuity by eccentric viewing. Over 90% of those fitted with prisms showed an improvement in acuity and performed better on locomotion tests.

A review of peripheral visual control of eye movements suggests that such control may be easier if the direction of the extrafoveal locus used is orthogonal rather than radial to the direction of target motion. When the extrafoveal locus lies parallel (radial) to the direction of target or eye motion, artificial feedback is usually required to avoid reflexive foveation. These findings have important implications for training eccentric viewing in low vision patients with central scotomata.

Young children (in general) and adults with central retinal lesions are often difficult to assess visually. Because of fixational drift and/or eccentric viewing, visual fields are particularly hard to measure in these populations. We describe a relatively simple and rapid technique to determine visual fields in these two groups using commercially available equipment.

We report the management of various aspects of the care provided over a span of 12 years for a patient with age-related maculopathy (ARM). The use of a low-power telescope proved to be particularly helpful because, with it, she learned eccentric viewing and made best use of her remaining vision.

IntroductionIn addition to optical devices, closed-circuit televisions (CCTVs) and eccentric viewing training are both recognized interventions to improve reading performance in individuals with vision loss secondary to age-related macular degeneration. Both are relatively expensive, however, either in the cost of the device or in the amount of time personnel need to provide training. In this randomized trial, we compared the effectiveness of these two interventions.MethodsParticipants with age-related macular degeneration and visual acuity between 6/48 (20/160) and 6/120 (20/400) first received basic low vision care, including optical devices. At the subsequent baseline visit, they undertook a battery of measures including logMAR visual acuity; reading speed and accuracy for text in 1.3M and 1M fonts; reading information on medicine bottles, utility bills, and food packages; the NEI-VFQ; the Geriatric Depression Scale; and a reading inventory questionnaire. They were then randomized to either obtaining a CCTV for home use or eccentric viewing training over the following six weeks.ResultsRecruitment was more difficult than expected for this population. Of 145 patients referred, 29 met the inclusion-exclusion criteria, 14 were willing to enroll, and 10 completed the trial. For the primary outcome (reading speed for 1.3M print), there was a significant improvement between baseline and outcome for the CCTV group (p = 0.005), but not for the eccentric viewing training group (p = 0.28), and the CCTV group showed significantly greater change (p = 0.04). There was a nonsignificant improvement in reading speed for 1M text and a decrease in the amount of time taken to read utility bill information in the CCTV group. There was a significant improvement in near visual acuity with current glasses with eccentric viewing training. The other measures did not reach statistical significance.DiscussionRandomized clinical trials for low vision rehabilitation, particularly in the elderly population with vision loss, are challenging, but such trials are important for the allocation of resources. This trial showed early indications of more impact on reading performance from CCTV than eccentric viewing training.