Active clinical trials for "Amblyopia"

The purpose of the study is to determine whether a patch-free occlusion therapy leads to better visual outcomes in young children with amblyopia than standard-of-care occlusion therapy with an adhesive patch and whether this is associated with better adherence to the treatment.

Amblyopia, a developmental abnormality that impairs spatial vision, is a major cause of vision loss, resulting in reduced visual acuity and reduced sensitivity to contrast. This study uses psychophysical measures to study neural plasticity in both adults and children with amblyopia.

The purpose of this study is to determine whether viewing asynchronous movies leads to better visual outcomes in young children with amblyopia than standard-of-care occlusion therapy with an adhesive patch and whether this is associated with better adherence to treatment.

This project will assess whether there is a significant difference in compliance with patching in amblyopic patients whose parents are instructed to pinch the superior and inferior edges of the patch before applying (in order to improve comfort) versus patients whose parents are instructed to place the patch evenly around the orbit.

Amblyopia, with a prevalence rates of 3% in adult population, is a common cause of vision impairment. It is characterized by impaired vision in one or both eyes because of disruption of normal visual stimuli and underdevelopment of the visual cortex, leads to lifelong visual deficits affecting both monocular and binocular visual function. Common causes of amblyopia include refraction error, anisometropia, strabismus and visual deprivation arising from ptosis or congenital cataract. Our previous studies had shed light on the relationship between abnormal early visual experience, and development of later amblyopia and possible neural developmental disorders. Functional recovery is difficult when neuroplasticity slows down at the end of the critical period. To date, there is no established effective treatment for adult amblyopia. Repetitive transcranial magnetic stimulation (rTMS) is one of the non-invasive stimulations had been used widely as a research tool to understand the brain functions and an established treatment modality in neuropsychiatric diseases. Theta burst stimulation (TBS) is a newer form of rTMS protocol which have a major advantage over traditional rTMS in their reduced administration duration and allowing stimulation at significantly lower intensities to attain comparable effects. TBS had been demonstrated to able to improve functions in participants with visual disorders. However, studies of its use on adult amblyopia are scarce. Due to lack of efficient treatment at present, it is of scientific significance to conduct placebo-controlled experiments on this topic. Investigators will evaluate the effect of three regimens of TBS (intermittent, continuous and sham), after one session and accumulative sessions, on visual functions of amblyopia adults shortly after treatment and 2 weeks later (lasting effect), in order to evaluate its potential role in amblyopia and find out the best paradigm for amblyopia treatment.

Amblyopia is a developmental condition that is characterized by reduced vision of the eye due to the presence of a sensory impediment during visual development, such as strabismus (ocular misalignment) or anisometropia (unequal refractive error), occurring early in life. Recent studies in humans and animals point towards a cortical locus for the processing deficit in amblyopia, revealing sensory deficits at the signal cell level. If changes in retinal neuronal function are also present, is unknown. Like in the brain, blood flow in the retina is coupled to neuronal activity. This phenomenon has been measured by different study groups with non invasive techniques in the brain and retina. It has been shown in previous studies that stimulating the retina with diffuse luminant flickering light increases retinal vessel diameter and blood flow. However, it is unknown whether this is also the case in the retina of amblyopic eyes. Additionally, the introduction of blood oxygen level dependent (BOLD) fMRI also makes it possible to directly access the vascular response in the brain to visual stimuli. Therefore, the aim of the present study is to investigate the effect of luminant flickering light on retinal vessel diameter and retinal blood flow in subjects with amblyopia. Also, oxygen saturation in retinal vessels will be assessed as well as pattern ERG for assessment of retinal function. Additionally, a high resolution image of the visual pathway will be taken with 7 Tesla MRI to investigate whether anatomical or functional alterations are present.

The purpose of this study is to test whether a binocular treatment can improve vision and motor function in young children with amblyopia. The proposed treatment is an animation series that has been modified so that different characters in the animation are presented to each eye. The contrast of the images shown to the amblyopic eye is higher than the contrast of the images shown to the fellow eye. The aim of the treatment is to promote co-operation between the two eyes and improve visual and motor outcomes. We will compare the benefits of this binocular treatment to patching, whereby the better eye is occluded with an eye patch for two hours per day to force the usage of the weaker eye. We hypothesize that the binocular treatment will improve vision and motor outcomes in young children with amblyopia, and that these improvements will be superior to any effects of patching.

To determine whether a binocular iPad game app is effective in improving visual acuity and reducing interocular suppression in amblyopic children To compare the amount of visual acuity improvement achieved with the binocular game app to the amount achieved with patching (standard treatment for amblyopia)

Amblyopia is the most common developmental vision disorder in children, caused by abnormal visual experience in early life, especially a difference in refraction between the eyes, a misalignment of the eye axes, a combination of both. Besides a significant reduced visual acuity, the patients show deficits in 3D vision and functional vision impairment like reduced reading speed, selective attention or motor control skills. The gold standard treatment for amblyopia, occlusion therapy, can lead to relapses or residual amblyopia (i.e., amblyopia that persist into adulthood). The current study aims to test the efficacy of a novel home-based child-friendly rehabilitation program for amblyopia, Vivid Vision Home, involving playing serious videogames on a virtual reality (VR) headset at home. The VR training will be compared to standard care (wearing a spectacle correction) and to age-matched typically developing individuals. A cross-over design will be used so that each participant will receive both treatments (games, spectacles). There is a growing number of studies showing benefits of binocular stimulation for visual acuity and stereovision, but provided mainly by level III studies, with a need for rigorous level I or II studies, using more engaging therapies, to confirm or refute the efficacy of this approach as an adjunct or replacement for current amblyopia treatments. Embedding binocular stimulation in engaging, immersive serious games delivered on VR headsets at home, as implemented by Vivid Vision Home, can address this question.

Photorefractive keratectomy (PRK) with excimer laser has been used successfully to treat myopia, hyperopia, and astigmatism in adults for over 35 years. Children with high refractive errors that go untreated will develop severe amblyopia. PRK can normalize high refractive errors and potentially improve the visual acuity in affected children. The purpose of this study is to investigate whether children with high anisometropia or isoametropia with amblyopia that are nonresponsive to standard therapy and receive PRK develop better longterm visual acuity.