View clinical trials related to Vision Disorders.
Filter by: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.
The purpose of this study is to evaluate reading performance in the visual periphery by simulating central vision loss using a computer-controlled gaze-contingent display with an eye tracker. Participants will read a page of text at a comfortable rate. Several manipulations hypothesized to improve reading will be tested, such as an inverted-text "spotlight" of a single word that follows the participant's gaze.
The investigators will re-investigate 150 children studied extensively in the past. 100 of these children were born to mothers prescribed methadone during their pregnancy because of opiate dependency, and 50 were comparison children who were not exposed to drugs. These children were investigated when they were newborn babies, and again when they were six months old, and a quarter of the drug-exposed babies had problems with their eyesight, whilst very few of the comparison children has eyesight problems. The investigators would like to see whether the eyesight problems are still present in the children now that they are older. Because they are older, more detailed testing can be undertaken which will help to understand how drug exposure in the womb may have affected their eyesight. The investigators will recruit new, comparison children to the study to match the number of comparison children with the number of drug-exposed children. The findings will be relevant and important when advising mothers on drug use - both prescribed and illicit - when they are pregnant.
There are indications in the literature that binocular vision disorders may occur after cataract and corneal refractive surgery. It is not clear whether these problems are new or represent decompensation of previously existing conditions. However, the following significant study limitations exist in the current literature: 1) lack of attention to non-strabismic binocular vision disorders, 2) incomplete binocular vision assessment, 3) a validated symptom survey was not used, 4) diplopia was typically the only symptom studied, 5) retrospective study design, and 6) in the few prospective studies the sample sizes were small. Given the limitations in the current literature there is a need for further study of the prevalence and significance of binocular vision problems after cataract surgery and binocular vision and accommodative problems after corneal refractive surgery. This study aims to determine whether there is an increase in the prevalence of binocular vision problems after cataract surgery and accommodative and binocular vision disorders after refractive surgery.
Sellar area tumors such as pituitary adenoma, craniopharyngioma and meningioma, etc, commonly lead to visual impairment symptoms. Patients suffer from a loss of visual acuity (VA) and visual field defects (VF) due to a local compression on the optic chiasma by the tumor. In the management of these patients, it is an important goal to evaluate their visual function throughout the treatment, so as to predict the outcome of the visual function . Since the visual pathway contains a huge complex network of both structure and function, traditional simplex evaluation of VA and VF is obviously not enough. Former studies have revealed changes in the visual network and cortex structure in neurodegenerative diseases and optic neuritis, yet the functional and structural changes caused by local tumor compression and their relation to the visual cortex activity patterns needs further research. The objective of this research is to asses the visual function in patients with sellar area tumor 1 week preoperatively (baseline),72 hours postoperatively(checking point 1) and at 3 months follow up(checkpoint 2). By using multimodal evaluation including visual resting and task state fMRI, diffusion tensor imaging (DTI), etc. The investigators aim to reveal the changes in functional connectivity (FC), amplitude of low frequency fluctuation (ALFF), regional homogeneity (REHO) ,visual cortex activity patterns and tract-based spatial statistics (TBSS).
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.
This research study is evaluating an educational intervention for breast cancer survivors who have experienced changes in sexual function after ovarian suppression treatment to reduce the risk of breast cancer recurrence.
In industrialized nations diabetic retinopathy(DR) is the most frequent microvascular complication of type 2 diabetes mellitus and the leading cause of visual impairment and blindness in the working-age population. The well-accepted strategy for prevention and treatment of diabetic eye complications focused on confirmed diabetic retinopathy, diabetic macular edema, cataract, etc, and there was no definitive therapy for preclinical central visual acuity (CVA) impairment, mainly because of its unknown pathogenesis. In our previous population-based study, the prevalence rate of early CVA impairment was as high as 9.1%, and that obviously limits the effects of diabetic eye diseases prevention and early-stage treatment strategy. Of note, the choriocapillaris is the only route for metabolic exchange in the retina within the foveal avascular zone, it was speculated that early CVA impairment is related to diabetic choroidopathy (DC). Recent research shows that the decreased macular choriocapillaris vessel density (MCVD) in diabetic eye ,which indicating early ischemia, is already present before diabetic macular edema can be observed; we have observed subfoveal choroidal thickness (SFCT) decreased significantly in the early CVA impairment patients. However, up til now, there was no epidemiology report on early CVA impairment in Chinese diabetes population. In the present study, we plan to conduct a 10-year perspective cohort observation of 2217 Chinese type 2 diabetic residents without diabetic retinopathy, diabetic macular edema, cataract and other vision impairing diseases, trying to find out related physical and biochemical risk factors. The results will facilitate discriminating high risk groups of early CVA impairment in diabetic patients. In the same time, a quantitative relationship between SFCT change, MCVD change and CVA change will be established. This study will demonstrate the role of DC in the occurrence of preclinical CVA impairment, and provide important theoretic evidence of blocking agents which target on DC.
Mobile electronic devices (MED) including, smartphones and tablets, offer a new type of assistive technology for visually-impaired people (VIP). They offer the possibility to replace optical magnifiers for those with mild impairment, and braille or auditory for those with severe visual loss, using standard consumer devices, which are relatively cheap and convenient. However not all VIP and rehabilitation professionals are familiar with the devices and their potential. In this study VIP who are interested in purchasing a MED will be recruited and trained. The effectiveness of this training will be determined by assessing the usage of devices by the participants from completion of training to 6 months, using questionnaires, and by remote monitoring of their MED. Validated questionnaires will be used to measure changes in quality of life, depression, adaptation to vision loss, and ability to carry out everyday tasks, before and after training, and 6 months later. Ongoing support has been found to be important when introducing users to new technology, in the form of volunteers to provide assistance and advice. The standard "training course only" model will therefore be compared to a scheme in which each participant is paired with a "buddy" (a university student) who can provide continuing support by visiting the VIP regularly at home.