Subnormal visual acuity after compliant amblyopia therapy: residual/refractory amblyopia or co-existing pathology? - a retrospective analysis.

Purpose: To assess the prevalence of alternate etiology/co-existing pathology among patients with amblyopia, and to characterize factors contributing to over-diagnosis of amblyopia. Methods: We retrospectively reviewed records of children (from 1 January 2016 to 31 December 2019) who were initially diagnosed as "amblyopia" but later an alternate diagnosis for subnormal vision was established. Patients who had a best corrected visual acuity (BCVA) of ≤20/32 (0.2 logMAR) after compliant amblyopia therapy were divided into 2 groups: those with refractory amblyopia (BCVA improvement from baseline <1 logMAR line) and residual amblyopia (BCVA improvement from baseline >1 logMAR line). Data was collected for presence/absence of amblyogenic risk factors, history, ocular examination, and investigations leading to the final alternate diagnosis. We analyzed the factors that contributed to the initial over-diagnosis of amblyopia using the diagnostic error evaluation and research (DEER) taxonomy tool. Results: During the study period, 508 children with an initial diagnosis of amblyopia met the study criteria. Among these 508 children, 466 were diagnosed to have amblyopia alone, while 26 children (5.1%, median age: 7 years, 17 boys: 9 girls) were revised to have an alternate diagnosis/co-existing pathology. These 26 patients comprised of 2 groups: children referred to us as amblyopia but rediagnosed to have an alternate diagnosis; and a second subset, initially diagnosed by us to have amblyopia, but later found to have alternate diagnosis/co-existing pathology. Subclinical optic neuritis (50%, 13 children), and occult macular dystrophy (OMD) (38.4%, 10 children) were the most frequent alternative diagnoses. Children with ametropic amblyopia (8/26, 30.7%) were most frequently misdiagnosed. Risk factors that led to an initial diagnosis of amblyopia were: high refractive error and heterotropia in 7 patients each (26.9%), anisometropia in 12 (46.1%), and prior pediatric cataract surgery in 4(15.3%). No improvement in BCVA in 21/26 (80.7%) children led to suspicion of co-existing etiology. Other clues were optic disc pallor (11), subnormal color vision (7), history of parental consanguinity in 7, and preceding febrile illness/rhinitis in 1 child. The DEER taxonomy tool suggested that the most common reasons for diagnostic errors were over-emphasis on amblyopia. Conclusion: Our study suggests that 5% of children diagnosed with amblyopia might have co-existing/alternate etiology. Most common co-existing etiologies were subclinical optic neuropathy, and OMD. No improvement in BCVA, subtle history and examination findings prompted further workup. Not considering co-existing etiologies was the most common reason for an initial overdiagnosis of amblyopia.

Improving health-related quality of life in glaucoma during 11 years and its association with vision loss and treatment of the disease.

PURPOSE: To evaluate the impact of glaucoma on health-related quality of life (HRQoL) and mental health in the ageing population of Finland. METHODS: Altogether 7380 and 5774 Finnish individuals aged 30 years and older with known eye disease status were studied in 2000 and 2011, respectively, in two population-based surveys, including an 11-year follow-up of 4683 participants. Data on HRQoL (EQ-5D-3L, 15D), depression (BDI), psychological distress (GHQ-12) and eye disease diagnoses were obtained from self-reported assessments. Information on glaucoma was complemented with the medication, diagnosis and eye surgery data obtained from the Finnish Health Registries. Distance visual acuity was assessed using the Snellen eye chart test. In logistic regression analyses, data were corrected for age, gender and the most common comorbidities. RESULTS: Glaucoma patients with verified diagnosis (n = 192 in 2000, n = 202 in 2011) and individuals with self-suspected glaucoma (n = 100 in 2000, n = 41 in 2011) showed a significant decrease in their HRQoL. Glaucoma was also associated with worsened overall mental health based on BDI and GHQ-12 results. Visual impairment associated with glaucoma is the major determinant of the reduced HRQoL and mental health. Neither glaucoma medication nor glaucoma surgery affected these parameters. The impact of glaucoma on HRQoL and mental health diminished between 2000 and 2011 in a cross-sectional setting. The newly diagnosed glaucoma during the 11-year follow-up had a minimal effect on them. CONCLUSION: Glaucoma patients show reduced HRQoL and mental health, which is associated with vision loss regardless of the awareness or treatment of the disease. However, this effect seems to be diminishing over time, and the newly diagnosed glaucoma did not show a significant effect on either HRQoL or mental health.

Low Vision and Dry Eye: Does One Diagnosis Overshadow the Other?

SIGNIFICANCE: The prevalence of dry eye disease and low vision increases with age; they share risk factors and can be the result of underlying common causes. They are generally studied separately; however, combining these perspectives is relevant for research on assistive technology given that sustained focus affects the tear film because of decreased blinking rates. PURPOSE: The objective of this study was to elucidate to which extent dry eye disease risk factors, signs, and symptoms are assessed in low vision patients who receive an eye examination as part of their vision rehabilitation services. METHODS: Using a retrospective chart review, dry eye disease risk factors, signs, or symptoms were extracted from 201 randomly selected files that contained an eye examination in the past 5 years from two vision rehabilitation centers. RESULTS: Demographic variables of charts from the two sites did not differ (mean visual acuity, 0.85 logMAR [standard deviation, 0.53; range, 0 to 2.3]; mean age, 71.2 years [standard deviation, 19 years; range, 24 to 101 years]). Fifty charts (25%) mentioned at least one dry eye disease symptom. Sixty-one charts (30.3%) reported systemic medications that can exacerbate dry eye disease, whereas 99 (49.2%) contained at least one systemic disease thought to contribute to dry eye disease symptoms; 145 (72.1%) mentioned at least one type of ocular surgery. Artificial tears were documented in 74 charts (36.8%). Few specific dry eye tests were performed, with the exception of corneal integrity assessment reported in 18 charts (8.95%). CONCLUSIONS: Low vision patients have multiple risk factors for dry eye disease; however, dry eye disease tests were not frequently performed in comprehensive low vision eye examinations in this sample. More efforts should be made to assess dry eye disease to enhance comfort and functional vision, especially with the increasing demands of digital devices as visual aids.

Visual outcomes of audio-luminous biofeedback training for a child with idiopathic nystagmus / Desfechos visuais de treinamento de biofeedback audioluminoso em criança com nistagmo idiopático

ABSTRACT Microperimetry biofeedback training is a vision rehabilitation method that involves the training of attention and oculomotor control, and the rehabilitation of poorly located and non-functional preferred retinal loci. It can significantly improve distance and near visual acuity in age-related macular degeneration. Previous studies have shown that biofeedback training using electrical nystagmography can reduce nystagmus amplitude and increase foveation time. However, these improvements have not been sustained following training sessions. We hereby report a pediatric case of idiopathic nystagmus in an 11-year old patient treated with microperimetric biofeedback to improve visual acuity and fixation stability. The training had a beneficial impact, positively affecting fixation stability as well as distance and near reading vision. Subjectively, improvement in quality of life was also reported. Conversely to previous studies, the positive effects in this case were maintained for as long as twelve months following therapy. To the best of our knowledge, this is the first case with long-term benefits to be reported in the literature.(AU)

RESUMO O treinamento de biofeedback por microperimetria é um método de reabilitação da visão que envolve treinamento de atenção, controle oculomotor e reabilitação do locus preferencial de fixação da retina. Esse treinamento pode melhorar significativamente a acuidade visual para longe e perto na degeneração macular relacionada à idade. Estudos anteriores mostraram que o treinamento de biofeedback usando a nistagmografia elétrica pode reduzir a amplitude do nistagmo e aumentar o período de foveação. Entretanto, os resultados não se mantiveram após o término das sessões. Aqui é relatado um caso de tratamento com biofeedback por microperimetria para melhorar a acuidade visual e a estabilidade de fixação em uma criança de 11 anos de idade. O treinamento teve impacto benéfico e afetou positivamente a estabilidade da fixação e a visão para longe, para perto e de leitura. Subjetivamente, foi relatada melhoria da qualidade de vida. Em contraste com estudos anteriores, os efeitos positivos foram mantidos até 12 meses após a terapia. Até onde sabemos, este é o primeiro caso na literatura que relata benefícios de longo prazo.(AU)

VISUAL IMPAIRMENT AND MACULAR VASCULAR REMODELING SECONDARY TO RETROGRADE MACULOPATHY IN RETINAL DETACHMENT TREATED WITH SILICON OIL TAMPONADE.

PURPOSE: To assess the frequency of macular cysts (MCs) in retinal detachment treated with silicone oil and evaluate their impact on visual acuity and macular vascularization using optical coherence tomography-angiography. METHODS: Forty-three eyes of 41 patients treated with silicone oil for retinal detachment were retrospectively studied. Best-corrected visual acuity and 6- × 6-mm optical coherence tomography-angiography examination at least 3 months after silicone oil removal were reviewed. In eyes with MCs, cyst area was measured on the en face optical coherence tomography-angiography image using ImageJ. Density of superficial capillary plexus and area of superficial foveal avascular zone were generated by the optical coherence tomography-angiography. Density of deep capillary plexus and deep foveal avascular zone area were measured using ImageJ. RESULTS: Twenty-five eyes (58%) presented with MCs. Cysts were exclusively located in the inner nuclear layer in 60% of cases. Mean best-corrected visual acuity in the MC group was lower than that of the non-MC group (P = 0.012). Macular cyst area negatively correlated with best-corrected visual acuity (P = 0.0201). Density of superficial capillary plexus was higher in the MC group (P < 0.0001), whereas area of superficial foveal avascular zone was lower (P < 0.0001). Macular cyst area negatively correlated with density of deep capillary plexus (P < 0.001). CONCLUSION: The incidence of INL-MCs after silicone oil removal is high. These are associated with impaired vision and macular vascular remodeling. We highlight their similarity with the "retrograde maculopathy" phenomenon.

Case Report: Nutritional and Toxic Optic Neuropathy: A Diagnostic Dilemma.

SIGNIFICANCE: Nutritional and toxic optic neuropathies are rare disorders characterized by visual impairment due to optic nerve damage by a toxin, usually with coexisting nutritional deficiencies. Its pathophysiology is still unclear, and multiple mechanisms implicated act synergistically to bring about this condition. The decline in its incidence and its confusing clinical appearance make diagnosing nutritional and toxic optic neuropathies challenging. PURPOSE: This is an observational clinical case report of an atypical clinical case of a nutritional and toxic optic neuropathy with a subacute presentation and papilledema at the time of diagnosis. The patient provided written informed consent for medical information and images to be published. CASE REPORT: A 47-year-old man presented with progressive, painless bilateral decrease in central vision over 15 days. The patient had a long-standing history of alcohol abuse and was a heavy smoker. The examination revealed dyschromatopsia, 20/400 visual acuity on both eyes, and no relative afferent pupillary defect. Funduscopy revealed bilateral papilledema. A visual field test showed generalized depression with centrocecal involvement in the left eye. Laboratory studies evidenced decreased vitamin B12/B1 and red blood cell folate levels, increased acute phase reactants, hypertransaminasemia, and macrocytic anemia. Serologies and methanol in urine were negative. After the discontinuation of tobacco use and alcohol accompanied by vitamin supplementation, our patient's visual field, visual acuity, and papilledema improved remarkably. After 5 months, visual acuity and funduscopy were normal. CONCLUSIONS: Although some hallmark signs were visible in this case, its subacute presentation and the presence of papilledema at diagnosis caused some diagnostic uncertainty. Nutritional and toxic optic neuropathy is a rare and challenging diagnosis because of a lack of biomarkers. Eye care clinicians should consider nutritional and toxic optic neuropathies to prevent severe and irreversible visual damage resulting from underdiagnosis and mismanagement.

Visual rehabilitation of patients with corneal diseases.

BACKGROUND: Although most patients with visual impairment due to corneal diseases can be treated successfully with surgery, some require visual rehabilitation to restore reading ability. To evaluate the best LVAs especially in terms of reading speed and characterize this specific patient group we performed a prospective, randomized cross-over trial. METHODS: All 34 patients underwent a detailed examination (slit-lamp, funduscopy, SD-OCT, ETDRS) as screening. Only patients with corneal diseases without other ocular diseases were included. Reading-speed was assessed with International-Reading-Speed-Texts (IReST) consecutively with five different LVAs (low vision aids) during one day in a randomized cross-over design. Corneal haze was quantified with corneal densitometry (Pentacam). RESULTS: Patients were either visually impaired (n = 28), severely impaired (n = 4) or legally blind (n = 2). Patients read significantly faster with LVAs (p < 0.0001). Fastest reading speed could be achieved with video magnifier (CCTV). Optical magnifier and portable-electronic magnifier enabled significantly lower reading speeds (p < 0.01). In a subgroup of patients (VA < 3/60,n = 6) black background enabled patients to read significantly faster compared to white background (p = 0.03). CONCLUSION: Patients with low magnification requirement can be treated successfully with optical LVAs and portable-electronic magnifiers. More severely afflicted patients need a CCTV. Black background enables fastest reading-speeds, probably due to less blinding. Visual impairment can be estimated with corneal densitometry. Our trial confirms the capability of LVAs to successfully restore the reading ability in patients with corneal diseases, which is a crucial part of visual rehabilitation. TRIAL REGISTRATION: This trial was registered at the German Clinical Trials Register as DRKS00010887 at 09.08.2016.

Case Series: Late Postoperative Capsular Block Syndrome Causing Reduced Vision Years After Uncomplicated Cataract Surgery.

SIGNIFICANCE: Late postoperative capsular block syndrome is a treatable complication presenting months to years after cataract surgery using continuous curvilinear anterior capsulorhexis and a posterior chamber intraocular lens implantation. Patients may present to optometric practices because of symptom onset significantly after the immediate post-operative period. PURPOSE: The purpose of this study was to describe the defining clinical features, proposed pathophysiology, and treatment of late postoperative capsular block syndrome. Case 1 was a 68-year-old man who presented with a sudden onset of blurry vision in the right eye 2 years after uncomplicated cataract surgery. Clinical examination revealed turbid fluid distending the posterior lens capsule, a 2-D myopic shift, and an absence of intraocular inflammation. Laser posterior capsulotomy successfully released the trapped fluid and reversed the myopic shift without complication. Case 2 was a 67-year-old man who presented with a gradual onset of hazy vision in the right eye 7 years after uncomplicated cataract surgery. Cloudy fluid was observed to be filling the space between the intraocular lens and the posterior lens capsule, and the refractive error was stable. The fluid was liberated and visual function was restored with uncomplicated laser posterior capsulotomy. CONCLUSIONS: Patients with late postoperative capsular block syndrome may present with blurry vision months to years after cataract surgery performed with continuous curvilinear capsulorhexis and posterior capsule intraocular lens implantation. The defining clinical sign is entrapment of turbid fluid between the intraocular lens and the posterior capsule that may result in reduced vision or refractive error shift. Late postoperative capsular block syndrome is distinguishable from other late complications of cataract surgery, including delayed endophthalmitis or phacoantigenic uveitis, by lack of concurrent robust ocular inflammation.

Efficacy, Safety, and Durability of Voretigene Neparvovec-rzyl in RPE65 Mutation-Associated Inherited Retinal Dystrophy: Results of Phase 1 and 3 Trials.

PURPOSE: To report the durability of voretigene neparvovec-rzyl (VN) adeno-associated viral vector-based gene therapy for RPE65 mutation-associated inherited retinal dystrophy (IRD), including results of a phase 1 follow-on study at year 4 and phase 3 study at year 2. DESIGN: Open-label phase 1 follow-on clinical trial and open-label, randomized, controlled phase 3 clinical trial. PARTICIPANTS: Forty subjects who received 1.5×1011 vector genomes (vg) of VN per eye in at least 1 eye during the trials, including 11 phase 1 follow-on subjects and 29 phase 3 subjects (20 original intervention [OI] and 9 control/intervention [CI]). METHODS: Subretinal injection of VN in the second eye of phase 1 follow-on subjects and in both eyes of phase 3 subjects. MAIN OUTCOME MEASURES: End points common to the phase 1 and phase 3 studies included change in performance on the Multi-Luminance Mobility Test (MLMT) within the illuminance range evaluated, full-field light sensitivity threshold (FST) testing, and best-corrected visual acuity (BCVA). Safety end points included adverse event reporting, ophthalmic examination, physical examination, and laboratory testing. RESULTS: Mean (standard deviation) MLMT lux score change was 2.4 (1.3) at 4 years compared with 2.6 (1.6) at 1 year after administration in phase 1 follow-on subjects (n = 8), 1.9 (1.1) at 2 years, and 1.9 (1.0) at 1 year post-administration in OI subjects (n = 20), and 2.1 (1.6) at 1 year post-administration in CI subjects (n = 9). All 3 groups maintained an average improvement in FST, reflecting more than a 2 log10(cd.s/m2) improvement in light sensitivity at 1 year and subsequent available follow-up visits. The safety profile was consistent with vitrectomy and the subretinal injection procedure, and no deleterious immune responses occurred. CONCLUSIONS: After VN gene augmentation therapy, there was a favorable benefit-to-risk profile with similar improvement demonstrated in navigational ability and light sensitivity among 3 groups of subjects with RPE65 mutation-associated IRD, a degenerative disease that progresses to complete blindness. The safety profile is consistent with the administration procedure. These data suggest that this effect, which is nearly maximal by 30 days after VN administration, is durable for 4 years, with observation ongoing.

Current Approaches to Low Vision (Re)Habilitation

With increased life expectancy at birth and especially the rising incidence of age-related macular degeneration, low vision (re)habilitation is becoming more important today. Important factors to consider when presenting rehabilitation and treatment options to patients presenting to low vision centers include the diagnosis of the underlying disease, the patient's age, their existing visual functions (especially distance and near visual acuity), whether visual loss is central or peripheral, whether their disease is progressive or not, the patient's education level, and their expectations from us. Low vision patients must be guided to the right centers at the appropriate age, with appropriate indications, and with realistic expectations, and the rehabilitation process must be carried out as a multidisciplinary collaboration.

Evaluación oftalmológica en niños derivados a un proyecto de rehabilitación en baja visión de un organismo de apoyo social / Ophthalmological evaluation in children referred to a low-vision rehabilitation project of a social assistance agency

INTRODUCCIÓN: Un niño con baja visión (BV) rehabilitado puede tener una educación integral. Objetivo: Estudiar el perfil de los escolares derivados para evaluación a un Proyecto de Rehabilitación en un organismo de apoyo social. PACIENTES Y MÉTODO: Estudio transversal descriptivo de beneficiarios evaluados entre septiembre 2015 y septiembre 2016 en JUNAEB. Se consideró diagnóstico de derivación, agudeza visual monocular (AV) con corrección óptica para lejos (cartillas Feinbloom) y cerca (cartillas Zeiss). Se clasificaron según AV y perimetría. Se consideró éxito de tratamiento lograr AV > 0,4 para le jos y/o cerca con ayuda óptica. RESULTADOS: Se evaluaron 278 escolares. 153 (55%) fueron hombres, 121(43,5%) entre 10 a 14 años. Catarata congénita bilateral, distrofias retinales, alta miopía, atrofia óptica y nistagmus congénito fueron las patologías más frecuentes. 224 (80,6%) se habilitaron con ayudas. 85 (37,9%) presentaron BV moderada y 63 (28,6%) BV severa. 122 (54,5%) presentaban perimetría normal, 68 (30,4%) campo visual (CV) tubular, 19 (8,5%) defecto sectorial del CV y 15 (6,7%) compromiso central del CV. 198 (88,4%) escolares lograron éxito visual de lejos y todos lograron éxito visual de cerca. 48 (17,2%) escolares no pudieron ser rehabilitados, estando asocia dos a una afección neuroftalmológica (41,7%), alto error refractivo (16,6%) o glaucoma congénito (10,4%). 6 (2,2%) casos mejoraron su AV con nueva corrección óptica. CONCLUSIÓN: El éxito obtenido demuestra la necesidad de habilitar visualmente a escolares con BV. Nuestro desafío es mantener este programa y educar al oftalmólogo prestador para una derivación oportuna.

INTRODUCTION: A low-vision (LV) rehabilitated child can receive comprehensive education. OBJECTIVE: To study the profile of school children referred for evaluation to a rehabilitation project in a social assistance agency. PATIENTS AND METHODS and Method: Descriptive cross-sectional study of beneficiaries evaluated between September 2015 and September 2016 in the National Board of School Assistan ce and Scholarships (JUNAEB). The referral diagnosis, monocular visual acuity (VA) with optical correction at far (Feinbloom chart) and close (Zeiss chart) distances were considered. They were classified according to VA and perimetry. Treatment success was considered if VA reaches > 0.4 at far and/or close distances with optical devices. RESULTS: 278 students were assessed. 153 (55%) were men, 121 (43.5%) between the ages of 10 to 14. Bilateral congenital cataract, retinal dystrophies, high myopia, optic atrophy, and congenital nystagmus were the most frequent pathologies. 224 students (80.6%) received optical devices. 85 (37.9%) presented moderate LV and 63 (28.6%) severe LV; 122 (54.5%) presented normal perimetry, 68 (30.4%) tubular Visual Field (VF), 19 (8.5%) sectoral VF defects, and 15 (6.7%) central scotoma. 198 (88.4%) students achieved visual success at a far distance and all achieved visual success at a near distance. 48 (17.2%) students could not be rehabilitated due to a neuro-ophthalmological condition (41.7%), high refractive error (16.6%) or congenital glauco ma (10.4%).Six (2.2%) cases improved VA with a new optical correction. CONCLUSION: This success demonstrates the need to provide low vision aids to schoolchildren with LV. Our challenge is to maintain this program and to educate ophthalmologist for timely referral.

Typeface features and legibility research.

In the early 20th century, reading researchers expressed optimism that scientific study of reading would improve the legibility of typefaces. Font-making was, however, complex, expensive and impractical for reading research, which was therefore restricted to standard commercial fonts. The adoption of computer typography in legibility studies makes the measurement, modification and creation of experimental fonts easier, while display of text on computer screens facilitates reading studies. These technical advances have spurred innovative research. Some studies continue to test fonts for efficient reading in low vision as well as normal vision, while others use novel fonts to investigate visual mechanisms in reading. Some experimental fonts incorporate color and animation features that were impractical or impossible in traditional typography. While it is not clear that such innovations will achieve the optimistic goals of a century ago, they extend the investigation and understanding of the nature of reading.

[Evaluation of the quality of life of adult patients treated in low vision at the CHU-IOTA]. / Évaluation de la qualité de vie des patients adultes pris en charge en basse vision au CHU-IOTA.

INTRODUCTION: Visual impairment is a handicap defined as any alteration of visual function responsible for a partial or total limitation of the activities of daily living (OMS, 2004). The objective of this study is to assess quality of life in patients before and after management of low vision. PATIENTS AND METHODS: This was a mono-centric, transverse, analytical study over a period of 6 months. Our study population included all adult patients seen in ophthalmologic consultation and followed in the low vision unit with visual acuity less than 3/10 and greater than or equal to 1/20 in the best eye with best optical correction. The National Eye Institute's quality of life questionnaire, the NEF VFQ 25, was administered to patients on site prior to management and then a month later. RESULTS: Low-vision management improved overall the dimensions of the quality of life questionnaire. Following the end-of-care assessment, the score for ocular pain was lowest (38.20), followed by the overall vision score (44.95) and near vision difficulty score (45.33). DISCUSSION: Our sample population was distinguished by a cultural mix, with diversity of beliefs and lifestyles, and also by the relatively advanced age of the subjects constituting it. This can influence the individual's perception of him- or herself within his or her environment, modifying the patient's estimation of his or her condition and therefore his or her behavior. CONCLUSION: Low-vision rehabilitation can improve the quality of life of visually impaired patients, particularly for near vision, activities of daily living and psychological health.

The prevalence of visually significant cataract in the Australian National Eye Health Survey.

PURPOSE: To describe the prevalence of visually significant cataract in Indigenous and non-Indigenous Australians. METHODS: A total of 3098 non-Indigenous Australians aged 50 years and over and 1738 Indigenous Australians aged 40 years and over, residing in 30 randomly selected Australian sites, were examined as part of the population-based National Eye Health Survey (NEHS). For those with visual acuity worse than 6/12, photos of the anterior and posterior segment were taken with a nonmydriatic fundus camera and assessed for cataract. Visually significant cataract was assigned in eyes with best-corrected visual acuity worse than 6/12 and cataract that was determined to be the primary cause of vision loss in that eye. RESULTS: In total, 99.2% (4797/4836) participants had complete data for visual acuity and cataract assessment. The overall weighted prevalence of visually significant cataract was 2.7% (95% CI: 2.0, 3.5) in non-Indigenous Australians and 4.3% (95% CI: 3.1, 5.9) among Indigenous Australians. After adjusting for age and gender, the odds of visually significant cataract were almost three times higher among Indigenous participants compared to non-Indigenous participants (adjusted odds ratio (OR) 2.95, 95% CI: 2.03, 4.29). Only 54.8% of non-Indigenous Australians and 38.9% of Indigenous Australians with visually significant cataract self-reported a known history of cataract. CONCLUSIONS: Our results suggest that continued efforts are required to build sustainable cataract surgery services within Indigenous communities. Furthermore, given the significant ageing of the Australian population, maintaining high cataract surgery rates amongst the non-Indigenous population is critical to reduce cataract-related vision loss.

Gaze behavior during navigation with reduced acuity.

Navigating unfamiliar indoor spaces while visually searching for objects of interest is a challenge faced by people with visual impairment. We asked how restricting visual acuity of normally sighted subjects would affect visual search and navigation in a real world environment, and how their performance would compare to subjects with naturally occurring low vision. Two experiments were conducted. In the first, 8 normally sighted subjects walked along an indoor path, looking for objects placed at unpredictable intervals to the left and right of the path, and identified single letters posted on the objects. A head-mounted eye tracker was used to assess their gaze direction in the environment. For half the trials, blur foils were used to restrict visual acuity to approximately logMAR 1.65. Gaze behavior, travel time, and letter recognition accuracy were compared between blurred and unrestricted conditions. In the second experiment, the same procedure was conducted, but performance was compared between acuity-restricted normally-sighted subjects and subjects with naturally occurring low vision (mean acuity 1.09 logMAR, range 0.48-1.85 logMAR). In Experiment 1, neither Blur nor the Letter Recognition Task individually had a statistically significant effect on travel time. However, when combined, there was an interaction between the two that increased travel time by approximately 63%, relative to baseline trials. Blur modified gaze behavior such that subjects spent more time looking down toward the floor while walking, at the expense of time spent looking in other directions. During Letter Recognition Task trials with Blur, subjects spent extra time examining objects, though more objects were missed altogether. In Experiment 2, low-vision subjects spent more time looking toward the boundary between the floor and the wall, but gaze patterns were otherwise similar to acuity-restricted subjects with normal vision. Low-vision subjects were also more likely to miss objects compared to acuity-restricted subjects. We conclude that under conditions of artificially restricted acuity, normally sighted subjects look downward toward the floor more frequently while navigating and take extra time to examine objects of interest, but are less likely to detect them. Low-vision subjects tend to direct their gaze toward the boundary between the wall and the floor, which may serve as a high contrast cue for navigation.

A Vision Enhancement System to Improve Face Recognition with Central Vision Loss.

SIGNIFICANCE: The overall goal of this work is to validate a low vision aid system that uses gaze as a pointing tool and provides smart magnification. We conclude that smart visual enhancement techniques as well as gaze contingency should improve the efficiency of assistive technology for the visually impaired. PURPOSE: A low vision aid, using gaze-contingent visual enhancement and primarily intended to help reading with central vision loss, was recently designed and tested with simulated scotoma. Here, we present a validation of this system for face recognition in age-related macular degeneration patients. METHODS: Twelve individuals with binocular central vision loss were recruited and tested on a face identification-matching task. Gaze position was measured in real time, thanks to an eye tracker. In the visual enhancement condition, at any time during the screen exploration, the fixated face was segregated from background and considered as a region of interest that could be magnified into a region of augmented vision by the participant, if desired. In the natural exploration condition, participants also performed the matching task but without the visual aid. Response time and accuracy were analyzed with mixed-effects models to (1) compare the performance with and without visual aid and (2) estimate the usability of the system. RESULTS: On average, the percentage of correct response for the natural exploration condition was 41%. This value was significantly increased to 63% with visual enhancement (95% confidence interval, 45 to 78%). For the large majority of our participants (83%), this improvement was accompanied by moderate increase in response time, suggesting a real functional benefit for these individuals. CONCLUSIONS: Without visual enhancement, participants with age-related macular degeneration performed poorly, confirming their struggle for face recognition and the need to use efficient visual aids. Our system significantly improved face identification accuracy by 55%, proving to be helpful under laboratory conditions.

23G pars plana vitrectomy for vitreal floaters: prospective assessment of subjective self-reported visual impairment and surgery-related risks during the course of treatment.

PURPOSE: Quantifying the subjective impairment due to floaters based on an indication-specific questionnaire and setting its change between prior to and 3/12 months after elective vitrectomy in relation to surgical risks. METHODS: Single-arm longitudinal observational multicenter study. Sixty-four floater patients underwent 23G pars plana vitrectomy; simultaneous phacoemulsification was excluded. An overall self-rated impairment index (SRI) and sub-indices SRI were calculated on the basis of a modified Visual Quality of Life questionnaire (VQoL), which addresses general vision, glare, near-sight problems and mobility of floaters. SRI ranged from 0 to 100% (maximum impairment). Secondary endpoints included corrected visual acuity and complications. RESULTS: Data were collected prior to and 3 (n = 64) and 12 (n = 62) months after surgery. The median overall SRI improved (44, 12, 11%) with a statistically significant median reduction of 69% (95% confidence interval 50-89%) 3 months postop. The median sub-SRIs improved for glare (50, 17, 17%), near sight problems (50, 17, 8%), and mobility of floaters (43, 5, 0%). Sixteen eyes needed cataract surgery during follow-up (10 showed cataract already prior to vitrectomy). Eight complications were reported (6 intra-operative retinal holes, 2 post-operative retinal detachments). CONCLUSION: For the majority of floater patients, subjective impairment was profoundly reduced by vitrectomy. Benefits of surgery prevailed despite complications.

Frontalis Muscle Contraction and the Role of Visual Deprivation and Eyelid Proprioception.

PURPOSE: To determine if frontalis muscle contraction can be induced by manipulating visual and eyelid proprioceptive inputs through simulating visual deprivation and ptosis. METHODS: Volunteers without prior eyelid or forehead pathologic study were recruited for this nonrandomized, prospective study. Baseline and study phase brow positions were documented. The first phase was to simulate visual deprivation and the second to simulate ptosis. The dominant eye was used for each phase. As a proxy to simulate visual field deprivation, a black contact lens was placed on the eye, which reduced vision to light perception. As a proxy to simulate ptosis, an external eyelid weight was placed on the upper eyelid. Brow position ratios were calculated at various points along the brow and statistical analysis was performed. RESULTS: Fifteen subjects participated. The average brow position ratio was 1.00 ± 0.08 for the visual deprivation group, which was not different from baseline (p = 0.86). The average brow position ratio for the external eyelid weight group was 1.13 ± 0.07, which was statistically significant compared with baseline and the visual deprivation group (p < 0.001). CONCLUSIONS: Inducing visual deprivation with a black contact lens does not lead to a change in brow position. However, placing an external eyelid weight does lead brow elevation, with an average increase of 13% from baseline. This suggests a likely role for proprioceptive or sensory inputs in frontalis muscle contraction in the setting of eyelid ptosis.