Multidisciplinary visual rehabilitation in low- and middle-income countries: a systematic review.

OBJECTIVE: To systematically review the evidence for effectiveness of rehabilitation interventions in people who are visually impaired, living in low- and middle-income countries. METHODS: Fifteen databases and the grey literature were searched up until February 2020; papers were identified according to eligibility criteria, and assessed for risk of bias. Eligible studies were controlled trials (randomised or non-randomised) of rehabilitation interventions for blind or visually impaired adults or children from low- and middle-income countries. Possible outcomes included visual acuity, activities of daily living, safety, quality of life and psychological status. RESULTS: Fifteen eligible studies were identified from India, Turkey, Nigeria, Croatia and Iran. Six studies were randomised, seven were non-randomised trials, and in two the method of allocation was not clear. Participants were adults, children and both adults and children. Seven studies were small (n ≤ 65) and examined the effect of training programmes. Remaining studies compared the effect of low vision aids, economic rehabilitation, goalball, rehabilitation compliance and service delivery methods, including one large four-arm randomised trial (n = 436). Studies measured a variety of outcomes, and mostly showed a positive effect of interventions for pre- and post-intervention assessment, although between intervention group comparisons were often inconclusive. Overall, only four studies had a low risk of bias. CONCLUSIONS: A lack of high-quality evidence for rehabilitation interventions is a barrier to provision of low vision services in low- and middle-income countries. Future research should focus on establishing effectiveness and cost-effectiveness of devices and models of vision rehabilitation appropriate for low-resource settings.IMPLICATIONS FOR REHABILITATIONThe systematic review found a lack of high-quality evidence for rehabilitation interventions is a barrier to provision of low vision services in low- and middle-income countries.Consider how visual rehabilitation interventions which have been shown to be effective can be delivered by non-specialists.Ensure that service providers for people who are visually impaired are trained in recognising depression and anxiety and have pathways for referral to mental health services, as appropriate.

Outcomes After Comprehensive Vision Rehabilitation Using Vision-related Quality of Life Questionnaires: Impact of Vision Impairment and National Eye Institute Visual Functioning Questionnaire.

SIGNIFICANCE: This research is significant because, although vision-related quality of life (VRQoL) is improved after vision rehabilitation (VR), patients with certain characteristics respond less positively on VRQoL measures, and this should inform future care. PURPOSE: The purposes of this study were to evaluate how two VRQoL questionnaires compare in measuring change in patient-reported outcomes after VR and to determine if patient characteristics or occupational therapy (OT) predict higher scores after rehabilitation. METHODS: In a prospective clinical cohort study, 109 patients with low vision completed the Impact of Vision Impairment (IVI) and the National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) before and after VR. Comprehensive VR included consultation with an ophthalmologist and OT if required. The relationships of six baseline characteristics (age, sex, visual acuity, contrast sensitivity, field loss, diagnosis) and OT were assessed with VRQoL scores using multivariable logistic regression. RESULTS: The mean (SD) age was 68.5 (19.2) years, and 61 (56%) were female. After rehabilitation, increases in scores were observed in all IVI subscales (reading [P < .001], mobility [P = .002], well-being [P = .0003]) and all NEI VFQ-25 subscales (functional [P = .01], socioemotional [P = .003]). Those who were referred to OT but did not attend and those who had hemianopia/field loss were less likely to have higher VRQoL in IVI mobility and well-being. Those attending OT for more than 3 hours were less likely to have better scores in emotional NEI VFQ. Men were less likely to have increased scores in functional and emotional NEI VFQ, whereas those with diagnoses of nonmacular diseases had higher odds of having increased scores on the emotional NEI VFQ (all, P < .05). CONCLUSION: Both the IVI and the NEI VFQ-25 detected change in patients' VRQoL after rehabilitation. Most of the patient characteristics we considered predicted a lower likelihood of increased scores in VRQoL.

Visual acuity and contrast sensitivity are two important factors affecting vision-related quality of life in advanced age-related macular degeneration.

PURPOSE: Vision loss from age-related macular degeneration (AMD) has a profound effect on vision-related quality of life (VRQoL). The pupose of this study is to identify clinical factors associated with VRQoL using the Rasch- calibrated NEI VFQ-25 scales in bilateral advanced AMD patients. METHODS: We retrospectively reviewed 47 patients (mean age 83.2 years) with bilateral advanced AMD. Clinical assessment included age, gender, type of AMD, high contrast visual acuity (VA), history of medical conditions, contrast sensitivity (CS), central visual field loss, report of Charles Bonnet Syndrome, current treatment for AMD and Rasch-calibrated NEI VFQ-25 visual function and socioemotional function scales. The NEI VFQ visual function scale includes items of general vision, peripheral vision, distance vision and near vision-related activity while the socioemotional function scale includes items of vision related-social functioning, role difficulties, dependency, and mental health. Multiple regression analysis (structural regression model) was performed using fixed item parameters obtained from the one-parameter item response theory model. RESULTS: Multivariate analysis showed that high contrast VA and CS were two factors influencing VRQoL visual function scale (ß = -0.25, 95% CI-0.37 to -0.12, p<0.001 and ß = 0.35, 95% CI 0.25 to 0.46, p<0.001) and socioemontional functioning scale (ß = -0.2, 95% CI -0.37 to -0.03, p = 0.023, and ß = 0.3, 95% CI 0.18 to 0.43, p = 0.001). Central visual field loss was not assoicated with either VRQoL visual or socioemontional functioning scale (ß = -0.08, 95% CI-0.28 to 0.12,p = 0.44 and ß = -0.09, 95% CI -0.03 to 0.16, p = 0.50, respectively). CONCLUSION: In patients with vision impairment secondary to bilateral advanced AMD, high contrast VA and CS are two important factors affecting VRQoL.

Calibrating the Impact of Vision Impairment (IVI): Creation of a Sample-Independent Visual Function Measure for Patient-Centered Outcomes Research.

PURPOSE: Provide item calibrations estimated for the Impact of Vision Impairment (IVI) questionnaire by pooling data from several studies of people with vision impairment (VI) representing a variety of countries and causes of VI. METHODS: Eight data sets from six principal investigators representing responses to IVI items from 2867 VI patients were pooled for analysis. Eligible patients were 18 years or older and from Australia, India, and the United States. Rasch analysis, using the Andrich Rating Scale Model (Winsteps version 3.65), was performed on preintervention IVI responses to estimate item and person measures, reliability coefficients, and response category thresholds. Differential item functioning (DIF) analysis and analysis of variance (ANOVA) were used to examine the effects different data sets and covariates on item estimates. RESULTS: Patient age range was 18 to 103 years (median 62 years); 55% were male. Visual acuity ranged from 20/20 to no light perception and primary diagnosis was macular degeneration in 29% of patients. Item measure estimates showed good separation reliability (R 2 = 0.99). DIF magnitude did not preclude use of all IVI-28 data. ANOVA showed VA (P < 0.001) and gender (P < 0.002) were predictors of visual ability. CONCLUSIONS: Analysis from pooled data support the provision of calibrated IVI item measures for researchers and clinicians to use, thus better enabling direct comparisons of patients with VI. TRANSLATIONAL RELEVANCE: Validity testing of the IVI show that we can combine disparate data sets of patient responses to calibrate item measures and response category thresholds, and provide to others for use in comparing patients across clinical trials and on an individual basis.

Communication Skills Training in Ophthalmology: Results of a Needs Assessment and Pilot Training Program.

OBJECTIVE: To conduct a needs assessment to identify gaps in communication skills training in ophthalmology residency programs and to use these results to pilot a communication workshop that prepares residents for difficult conversations. DESIGN: A mixed-methods design was used to perform the needs assessment. A pre-and postsurvey was administered to workshop participants. SETTING: Mass Eye and Ear Infirmary, Harvard Medical School (HMS), Department of Ophthalmology. PARTICIPANTS: HMS ophthalmology residents from postgraduate years 2-4 participated in the needs assessment and the workshop. Ophthalmology residency program directors in the United States participated in national needs assessment. METHODS: Ophthalmology program directors across the United States were queried on their perception of resident communication skills training through an online survey. A targeted needs assessment in the form of a narrative exercise captured resident perspectives on communication in ophthalmology from HMS residents. A group of HMS residents participated in the pilot workshop and a pre- and postsurvey was administered to participants to assess its effectiveness. RESULTS: The survey of program directors yielded a response rate of 40%. Ninety percent of respondents agreed that the communication skills training in their programs could be improved. Fifteen of 24 residents (62%) completed the needs assessment. Qualitative analysis of the narrative material revealed four themes; (1) differing expectations, (2) work role and environment, (3) challenges specific to ophthalmology, and (4) successful strategies adopted. Nine residents participated in the workshop. There was a significant improvement post-workshop in resident reported scores on their ability to manage their emotions during difficult conversations (p = 0.03). CONCLUSIONS: There is an opportunity to improve communication skills training in ophthalmology residency through formalized curriculum.

Adding access to a video magnifier to standard vision rehabilitation: initial results on reading performance and well-being from a prospective, randomized study.

PURPOSE: Both optical and electronic magnification are available to patients with low vision. Electronic video magnifiers are more expensive than optical magnifiers, but they offer additional benefits, including variable magnification and contrast. This study aimed to evaluate the effect of access to a video magnifier (VM) added to standard comprehensive vision rehabilitation (VR). METHODS: In this prospective study, 37 subjects with central field loss were randomized to receive standard VR (VR group, 18 subjects) or standard VR plus VM (VM group, 19 subjects). Subjects read the International Reading Speed Texts (IReST), a bank check, and a phone number at enrollment, at 1 month, and after occupational therapy (OT) as indicated to address patient goals. The Impact of Vision Impairment (IVI) questionnaire, a version of the Activity Inventory (AI), and the Depression Anxiety and Stress Scale (DASS) were administered at enrollment, 1 month, after OT, 1 month later, and 1 year after enrollment. Assessments at enrollment and 1 month later were evaluated. RESULTS: At 1 month, the VM group displayed significant improvement in reading continuous print as measured by the IReST (P = 0.01) but did not differ on IVI, AI, or DASS. From enrollment to 1 month all subjects improved in their ability to spot read (phone number and check; P < 0.01 for both). The VM group improved in their ability to find and read a number in a phone book more than the VR group at 1 month after initial consultation (P = 0.02). All reported better well-being (P = 0.02). CONCLUSIONS: All subjects reported better well-being on the IVI. The VM group read faster and was better at two spot reading tasks but did not differ from the VR group in other outcome measures.

Stargardt Macular Dystrophy: Changes in Fixation When Asked to Look Straight Ahead.

PURPOSE: To examine whether individuals with Stargardt disease macular dystrophy (STGD) change the location of fixation with instruction. DESIGN: Case-control study. PARTICIPANTS: Thirteen normally sighted and 37 STGD participants. METHODS: Using an Optos scanning laser ophthalmoscopy/OCT microperimeter (Optos plc, Dunfermline, UK), fixation was measured under 2 different instructions: "look at the cross" (LC) and "look straight ahead, even if you do not see the cross" (LS). Visual acuity, contrast sensitivity, disease duration, and age at disease onset were obtained from medical records. MAIN OUTCOME MEASURE: Change in fixation with instruction. RESULTS: Mean age of the STGD participants was 39.2 years, and 24 were women. Mean acuity was 1.01±0.29 logarithm of the minimum angle of resolution (logMAR), and mean contrast sensitivity was 1.16±0.41 log. The largest number of fixations under the LC condition were in the superior retina. Patients with STGD were divided into 3 groups, depending on the change in fixation locus when asked to look straight ahead: those having fixation closer the fovea, those with no change in the location of fixation, and those looking farther away from the fovea. Fifty-one eyes of 32 participants had fixations closer to the fovea when asked to look straight ahead (average change, -6.3°), whereas 13 eyes of 11 participants did not change fixation. There were no significant differences between groups in age, visual acuity, contrast sensitivity, bivariate contour ellipse area, and age at disease onset. CONCLUSIONS: Despite having eccentric fixation, most STGD participants did not have a complete directional re-referencing from the fovea to the eccentric location, and moved fixation when asked to look straight ahead. This finding emphasizes that reliable assessment of visual function during evaluations of disease progression or in therapeutic intervention trials requires consistent instructions and monitoring of fixation. Otherwise, a patient's interpretation of fixation instruction may confound the results.

Translational Vision Rehabilitation: From Eccentric Fixation to Reading Rehabilitation.

Eccentric fixation is a commonly used adaptive strategy in patients with central vision loss. A common complaint in patients with central vision loss is reading difficulty. The mechanisms as to how and why eccentric fixation develops comprise an exciting area of research. As we better understand this phenomenon, we may apply these findings to the clinical setting and in particular to reading rehabilitation. Biofeedback is a new technique that can be applied to eccentric fixation and may have a role in reading rehabilitation.

Clinically Meaningful Rehabilitation Outcomes of Low Vision Patients Served by Outpatient Clinical Centers.

IMPORTANCE: To facilitate comparative clinical outcome research in low vision rehabilitation, we must use patient-centered measurements that reflect clinically meaningful changes in visual ability. OBJECTIVE: To quantify the effects of currently provided low vision rehabilitation (LVR) on patients who present for outpatient LVR services in the United States. DESIGN, SETTING, AND PARTICIPANTS: Prospective, observational study of new patients seeking outpatient LVR services. From April 2008 through May 2011, 779 patients from 28 clinical centers in the United States were enrolled in the Low Vision Rehabilitation Outcomes Study. The Activity Inventory, a visual function questionnaire, was administered to measure overall visual ability and visual ability in 4 functional domains (reading, mobility, visual motor function, and visual information processing) at baseline and 6 to 9 months after usual LVR care. The Geriatric Depression Scale, Telephone Interview for Cognitive Status, and Medical Outcomes Study 36-Item Short-Form Health Survey physical functioning questionnaires were also administered to measure patients' psychological, cognitive, and physical health states, respectively, and clinical findings of patients were provided by study centers. MAIN OUTCOMES AND MEASURES: Mean changes in the study population and minimum clinically important differences in the individual in overall visual ability and in visual ability in 4 functional domains as measured by the Activity Inventory. RESULTS: Baseline and post-rehabilitation measures were obtained for 468 patients. Minimum clinically important differences (95% CIs) were observed in nearly half (47% [95% CI, 44%-50%]) of patients in overall visual ability. The prevalence rates of patients with minimum clinically important differences in visual ability in functional domains were reading (44% [95% CI, 42%-48%]), visual motor function (38% [95% CI, 36%-42%]), visual information processing (33% [95% CI, 31%-37%]), and mobility (27% [95% CI, 25%-31%]). The largest average effect size (Cohen d = 0.87) for the population was observed in overall visual ability. Age (P = .006) was an independent predictor of changes in overall visual ability, and logMAR visual acuity (P = .002) was predictive of changes in visual information processing. CONCLUSIONS AND RELEVANCE: Forty-four to fifty percent of patients presenting for outpatient LVR show clinically meaningful differences in overall visual ability after LVR, and the average effect sizes in overall visual ability are large, close to 1 SD.

Feasibility of a web-based survey of hallucinations and assessment of visual function in patients with Parkinson's disease.

BACKGROUND: Patients with Parkinson's disease (PD) experience visual hallucinations, which may be related to decreased contrast sensitivity (ie, the ability to discern shades of grey). OBJECTIVE: The objective of this study was to investigate if an online research platform can be used to survey patients with Parkinson's disease regarding visual hallucinations, and also be used to assess visual contrast perception. METHODS: From the online patient community, PatientsLikeMe, 964 members were invited via email to participate in this study. Participants completed a modified version of the University of Miami Parkinson's disease hallucinations questionnaire and an online vision test. RESULTS: The study was completed by 27.9% (269/964) of those who were invited: 56.9% of this group had PD (153/269) and 43.1% (116/269) were non-Parkinson's controls. Hallucinations were reported by 18.3% (28/153) of the Parkinson's group. Although 10 subjects (9%) in the control group reported experiencing hallucinations, only 2 of them actually described formed hallucinations. Participants with Parkinson's disease with a mean of 1.75 (SD 0.35) and the control group with a mean of 1.85 (SD 0.36) showed relatively good contrast perception as measured with the online letter test (P=.07). People who reported hallucinations showed contrast sensitivity levels that did not differ from levels shown by people without hallucinations (P=.96), although there was a trend towards lower contrast sensitivity in hallucinators. CONCLUSIONS: Although more Parkinson's responders reported visual hallucinations, a significant number of non-Parkinson's control group responders also reported visual hallucinations. The online survey method may have failed to distinguish between formed hallucinations, which are typical in Parkinson's disease, and non-formed hallucinations that have less diagnostic specificity. Multiple questions outlining the nature of the hallucinations are required. In a clinical interview, the specific nature of the hallucination would be further refined to rule out a vague description that does not indicate a true, formed visual hallucination. Contrary to previous literature, both groups showed relatively good contrast sensitivity, perhaps representing a ceiling effect or limitations of online testing conditions that are difficult to standardize. Steps can be taken in future trials to further standardize online visual function testing, to refine control group parameters and to take steps to rule out confounding variables such as comorbid disease that could be associated with hallucinations. Contacting subjects via an online health social network is a novel, cost-effective method of conducting vision research that allows large numbers of individuals to be contacted quickly, and refinement of questionnaires and visual function testing may allow more robust findings in future research.

Characterization of field loss based on microperimetry is predictive of face recognition difficulties.

PURPOSE: To determine how visual field loss as assessed by microperimetry is correlated with deficits in face recognition. METHODS: Twelve patients (age range, 26-70 years) with impaired visual sensitivity in the central visual field caused by a variety of pathologies and 12 normally sighted controls (control subject [CS] group; age range, 20-68 years) performed a face recognition task for blurred and unblurred faces. For patients, we assessed central visual field loss using microperimetry, fixation stability, Pelli-Robson contrast sensitivity, and letter acuity. RESULTS: Patients were divided into two groups by microperimetry: a low vision (LV) group (n = 8) had impaired sensitivity at the anatomical fovea and/or poor fixation stability, whereas a low vision that excluded the fovea (LV:F) group (n = 4) was characterized by at least some residual foveal sensitivity but insensitivity in other retinal regions. The LV group performed worse than the other groups at all blur levels, whereas the performance of the LV:F group was not credibly different from that of the CS group. The performance of the CS and LV:F groups deteriorated as blur increased, whereas the LV group showed consistently poor performance regardless of blur. Visual acuity and fixation stability were correlated with face recognition performance. CONCLUSIONS: Persons diagnosed as having disease affecting the central visual field can recognize faces as well as persons with no visual disease provided that they have residual sensitivity in the anatomical fovea and show stable fixation patterns. Performance in this task is limited by the upper resolution of nonfoveal vision or image blur, whichever is worse.

Visual Function Endpoints to Enable Dry AMD Clinical Trials.

The slow progression of non-exudative age-related macular degeneration (dry AMD) presents challenges for drug discovery. The standard endpoint used for ophthalmic clinical trials, best-corrected visual acuity, is insensitive to the early stages and slow progression of dry AMD. Effective drug discovery for dry AMD treatments will therefore require novel applications of more effective visual function endpoints. This review will present candidates for visual function endpoints for dry AMD clinical trials. The promising visual assessments include contrast sensitivity, reading speed, microperimetry, and dark adaptation. Their adoption as exploratory endpoints in future trials will be critical for determining their accuracy, precision, and applicability, and ultimately determine their value for drug discovery.

Baseline traits of low vision patients served by private outpatient clinical centers in the United States.

OBJECTIVE: To characterize the traits of low vision patients who seek outpatient low vision rehabilitation (LVR) services in the United States. METHODS: In a prospective observational study, we enrolled 764 new low vision patients seeking outpatient LVR services from 28 clinical centers in the United States. Before their initial appointment, multiple questionnaires assessing daily living and vision, physical, psychological, and cognitive health states were administered by telephone. Baseline clinical visual impairment measures and disorder diagnoses were recorded. RESULTS: Patients had a median age of 77 years, were primarily female (66%), and had macular disease (55%), most of which was nonneovascular age-related macular degeneration. More than one-third of the patients (37%) had mild vision impairment with habitual visual acuity (VA) of 20/60 or greater. The VA correlated well with contrast sensitivity (r = -0.52) but poorly with self-reported vision quality. The intake survey revealed self-reported physical health limitations, including decreased endurance (68%) and mobility problems (52%). Many patients reported increased levels of frustration (42%) and depressed mood (22%); memory and cognitive impairment (11%) were less frequently endorsed. Patients relied on others for daily living support (87%), but many (31%) still drove. CONCLUSIONS: Most patients seeking LVR are geriatric and have macular disease with relatively preserved VA. The disparity between VA and subjective quality of vision suggests that LVR referrals are based on symptoms rather than on VA alone. Patients seen for LVR services have significant physical, psychological, and cognitive disorders that can amplify vision disabilities and decrease rehabilitation potential.

Visual search with image modification in age-related macular degeneration.

PURPOSE: AMD results in loss of central vision and a dependence on low-resolution peripheral vision. While many image enhancement techniques have been proposed, there is a lack of quantitative comparison of the effectiveness of enhancement. We developed a natural visual search task that uses patients' eye movements as a quantitative and functional measure of the efficacy of image modification. METHODS: Eye movements of 17 patients (mean age = 77 years) with AMD were recorded while they searched for target objects in natural images. Eight different image modification methods were implemented and included manipulations of local image or edge contrast, color, and crowding. In a subsequent task, patients ranked their preference of the image modifications. RESULTS: Within individual participants, there was no significant difference in search duration or accuracy across eight different image manipulations. When data were collapsed across all image modifications, a multivariate model identified six significant predictors for normalized search duration including scotoma size and acuity, as well as interactions among scotoma size, age, acuity, and contrast (P < 0.05). Additionally, an analysis of image statistics showed no correlation with search performance across all image modifications. Rank ordering of enhancement methods based on participants' preference revealed a trend that participants preferred the least modified images (P < 0.05). CONCLUSIONS: There was no quantitative effect of image modification on search performance. A better understanding of low- and high-level components of visual search in natural scenes is necessary to improve future attempts at image enhancement for low vision patients. Different search tasks may require alternative image modifications to improve patient functioning and performance.

Temporal profile of functional visual rehabilitative outcomes modulated by transcranial direct current stimulation.

OBJECTIVES: We have previously reported that transcranial direct current stimulation (tDCS) delivered to the occipital cortex enhances visual functional recovery when combined with three months of computer-based rehabilitative training in patients with hemianopia. The principal objective of this study was to evaluate the temporal sequence of effects of tDCS on visual recovery as they appear over the course of training and across different indicators of visual function. METHODS: Primary objective outcome measures were 1) shifts in visual field border and 2) stimulus detection accuracy within the affected hemifield. These were compared between patients randomized to either vision restoration therapy (VRT) combined with active tDCS or VRT paired with sham tDCS. Training comprised two half-hour sessions, three times a week for three months. Primary outcome measures were collected at baseline (pretest), monthly interim intervals, and at posttest (three months). As secondary outcome measures, contrast sensitivity and reading performance were collected at pretest and posttest time points only. RESULTS: Active tDCS combined with VRT accelerated the recovery of stimulus detection as between-group differences appeared within the first month of training. In contrast, a shift in the visual field border was only evident at posttest (after three months of training). tDCS did not affect contrast sensitivity or reading performance. CONCLUSIONS: These results suggest that tDCS may differentially affect the magnitude and sequence of visual recovery in a manner that is task specific to the type of visual rehabilitative training strategy employed.