View clinical trials related to Visual Impairment.
Filter by:This study is a community trial that aims to establish and evaluate an mHealth screening and promotional tool for improving eye health in Iran. Sampling frame is a region in Tehran province with around 1 million sub-urban and rural inhabitants. investigators have obtained the list of health centers and their underserved population from the health authorities. In this region, health services are delivered through rural health houses, urban health posts and overhead health centers (221 units in total). investigators choose 27 units using cluster random sampling method with a probability proportional to size strategy, then investigators randomly assign them into three arms (explained below). The interventions will be at community level with the community as the unit of randomization. Arm 1- Training of the Primary Health Care (PHC) workers + PHC workers will be empowered with the mHealth tool to monitor, screen and promote community members Arm 2- PHC system will be strengthened with health promotion and screening programmes (same content as the mHealth tool) and PHC workers will deliver eye health messages and screening tests by the conventional facilities. Arm 3: Control group: only observation and registering of routine care
The aim of this study was to investigate the eye structure, visual impairment, visual motor development and motor coordination of children between 2-6 ages that had applied to diod laser photocoagulation and intravitreal anti - vascular endothelial growth factor treatment.
Patients with acute onset Vogt-Koyanagi-Harada disease (VKHD) was prospectively included in this study. They were systematically followed with clinical, posterior segment imaging exams and full-field electroretinogram during a minimum 24-month of follow-up. All patients were treated with 3-day methylprednisolone pulse therapy followed by 1mg/day oral prednisone with a slow tapper during a median of 13 months. Non-steroidal immunosuppressive therapy (IMT) was introduced in cases of refractory disease or in cases of prednisone intolerance. Outcome measured by full-field electroretinogram was analyzed and patient was grouped as electroretinogram stable or electroretinogram worsening. Clinical data was analyzed in these two electroretinogram-based groups.
This study is planned to test an educational intervention promoting the use of spectacles among secondary school children. It is based on the hypothesis that educating teachers, parents and children about the importance of wearing spectacles has the potential to increase spectacle wear among children.Reasons for non-compliance towards spectacle use will be explored and educational intervention will be planned considering these reasons. Educational intervention will increase awareness about the importance of spectacles use and reduce the barriers towards spectacle use.Reducing barriers will increase compliance towards spectacles use which will ultimately prevent the avoidable visual impairment.
Our study aims to validate the relevance of a virtual reality tool (VIRARE: VIrtual REality Assisted Rehabilitation) in the assessment and rehabilitation of visually impaired subjects.
Unilateral vestibular lesions are frequent and disabling pathologies causing a set of oculomotor, postural and perceptual symptoms. These symptoms reduce over time according to a vestibular compensation. However, vestibular compensation should be considered as a set of sub-processes whose duration and recovery level differ. Indeed, after a unilateral vestibular loss, some functions remain asymmetrical as a long-term effect, and these disorders may be observed among patients with no functional complaints. Balance disorders may persist in some patients. The equilibration consists in handling real-time a considerable amount of information coming from the environment and the subject himself, allowing an adaptation of the position and movements of his body to satisfy the needs of posture, balance and orientation. This information comes mainly from the vision, the vestibule and the somesthesic system. It is pre-treated and harmonized in the brainstem, before being transmitted to the higher brain centres. Brain centers thus learn about peripheral conditions. According to these and the project of the movement, brain centers address in response orders to ophtalmological and motor effectors ensuring look, posture and balance to be provided. The eye is a cornerstone of the balancing system through the retina, an environmental sensor, and its extraocular muscles, effectors of the system. The aim of this study is to assess the effects of acute unilateral vestibular loss on visual abilities evaluated by orthoptic balance in patients who presented acute unilateral vestibular loss by surgical deafferentation (removal of vestibular schwannoma, vestibular neurotomy or surgical labyrinthectomy for Meniere's disease), during the early phase and decline of vestibular compensation. Our secondary objective is to evaluate the effect of a pre-existing anomaly of the visual abilities evaluated by orthoptic assessment on the vestibular compensation capacities. All in all, this study seems crucial to improve the management of patients with unilateral vestibular dysfunction and contribute to improving their clinical management. As a standardized management of these patients, an audio-vestibular evaluation will be performed before surgery (-1D), after acute unilateral vestibular loss at the early stage (+7D), and then after vestibular compensation (+2M) as well as an orthoptic evaluation. A good tolerance of the orthoptic evaluation is expected in this surgical context.
An individual senses the world and reflects feedbacks via independent behaviors. Such precise collaboration of the sensory and behavioral systems is fundamental to survival and evolution. When a sensory modality is altered, the behavioral system has the potential to fit in a substitute modality. However, the specific dynamics of human behaviors in response to sensory loss remain largely unknown due to the paucities of representative situations and large-scale samples. Here, the investigators focused on thousands of human infants who suffered varying degrees of visual stimuli deficiency in early stages, while their behavioral systems remained sensitive and thus retained high behavioral plasticity. Having access to this unique population provides an unprecedented opportunity to investigate the effect of diverse visual conditions on the behavioral system.
As a subtype of major depressive disorder, seasonal affective disorder (SAD) or winter depression causes severe reductions in both quality of life and productivity and results in high morbidity and frequent sick leave (1). SAD is a prevalent disorder with rates as high as 3-5% in central European countries and 8-10% in Scandinavian countries. In our recent screening survey among persons with severe visual impairment or blindness (visual acuity < 6/60), we found a strikingly high prevalence of SAD of 17 % compared to 8% in the fully sighted control group. Persons with maintained light perception had a highly increased SAD prevalence of 18 % whereas no light perception (NLP) respondents had an SAD prevalence of 13 %. Light is unquestionably of great importance in the development and treatment of SAD. It is suggested that a reduced retinal sensitivity to light leads to sub-threshold light input to the brain and consequently to the development of SAD. The novel retinal non-visual photoreceptors, the intrinsically photosensitive retinal ganglion cells (ipRGCs), are involved in the regulation of circadian rhythm and mood and their function are in part independent of the function of the classical rod and cone photoreceptors which form the basis of conscious visual perception. Function of the ipRGCs can be assessed by chromatic pupillometry where the sustained pupillary contractions following blue light stimulation (PIPR) is the main outcome. In persons with SAD without eye disorder the function of the ipRGCs is reduced. We here wish to investigate associations between ipRGC function and SAD symptoms, circadian profile and treatment response to light therapy in persons with visual impairment. Persons with visual impairment (SAD and non-SAD) are assessed for ipRGC function with chromatic pupillometry, for seasonal mood variation by interview and questionnaire and for diurnal melatonin secretion by saliva analysis summer and winter. In winter SAD participants are treated with daily morning bright light for 6 weeks. Reduction in depression scores and tolerability is recorded.
Elderly with visual impairment (VI) who undergo community eye screening often do not attend tertiary follow-up even if significant eye diseases are detected. Investigators evaluate an incentive-care scheme (ICS) to improve the attendance rates of tertiary eye-care visits of participants following community eye screening.
The purpose of this study is to evaluate how visual acuity assessed with Peek Acuity (a cell phone application to check visual acuity) among preschool and school-aged children 3 to less than18 years of age (1) compares to the standard visual acuity exam in the ophthalmology clinic and (2) performs as a screening test for ocular abnormalities that warrant referral for an eye exam.