View clinical trials related to Exotropia.
Filter by:Strabismus is one of the most frequent ocular problems among developmentally normal children. The prevalence of strabismus varies among different regions, ranging from 0.06% in Japan to 5.65% in China. Exotropia is reported to be the most prevalent type of deviation in many of these studies. About 48-92% of the exotropic patients have intermittent exotropia (IXT). Jenkins reported that the prevalence of exodeviation was higher in countries near the Equator. Its prevalence is also higher in subequatorial Africa, the Middle East, and East Asia (where there is plenty of sunshine) in comparison to the USA and Central Europe. Intermittent exotropia is a disorder of binocular eye movement control, where one eye intermittently turns outward. The outward deviation is greatest and likely occurs at far distances viewing, when the oculomotor convergence effort is weakest, and occurs frequently when the patient is under stress, tired, ill, or in particular test situations. X(T) can also occur at near as convergence insufficiency.
This study evaluates the efficacy and safety of visual perceptual learning for improving stereopsis in intermittent exotropia. Half of participants will receive visual perceptual training using the Nu.T. The other half will not receive any training because there is no standard treatment for decreased stereopsis in intermittent exotropia.
The aim of this study is to evaluate the techniques of combined lateral rectus muscle recession with hang back and combined lateral rectus muscle recession with z-tenotomy in correcting large-angle exotropia.
V pattern strabismus is the commonest of alphabet pattern. Its identification is essential to plan a proper surgical management. Graded recession is a very logical approach to treat inferior oblique overaction (IOOA). The aim Is to evaluate the efficacy of graded recession of inferior oblique muscle for correction of different grades of V pattern.
Comparison Between The Results Of Two Muscles Surgery And Three Muscles Surgery For The Treatment Of Large Angle Exotropia
The current measurement methods of strabismus include the corneal light reflection method, prism alternate covering, etc., which especially rely on the subjective experience of doctors, and there is a large error between different measurers， leading to serious underestimation of strabismus prevalence and insufficient care for strabismus patients. Here, the investigators established and validated an artificial intelligence system to achieve an automatic diagnosis of strabismus based on patient-sourced videos of programmatic cover tests. Three-dimensional reconstruction methods are used to digitize the parameters of head and eye positions. This system has been integrated into a smartphone platform to be further validated through hospital-based and population-based clinical trials.
Determine whether full-time patching is more effective than observation for improving distance control of IXT after 3 months of treatment (on-treatment outcome).
Atropine is a non-selective muscarinic acetylcholine (M) receptor antagonist that paralyzes the ciliary muscle, dilates the pupil, and reduces the power of accommodation. Current studies have confirmed the effect of low concentrations of atropine drops in slowing the progression of myopia. In the atropine treatment for myopia (ATOM2) study, there was a rapid and dose-dependent decrease in accommodation after atropine drops: after 2 weeks of use, accommodation decreased from baseline 16.2D to 11.3D (4.9D) in the 0.01% atropine drops group, from baseline 16.7D to 3.8D (12.9D) in the 0.1% atropine group, and from baseline 15.8 D to 2.2 D (13.6 D) in the 0.5% atropine group; one year after withdrawal, there was some recovery of the accommodation in all the three groups, but it was still lower than the baseline values for each group, with a mean decrease of 2.56 D.Similar results were found in the Low-concentration Atropine for Myopia Progression (LAMP) Study by Janson C. Yam, 0.05% atropine drops reduced the accommodation by approximately 2D on average after 1 year of treatment. In general, if accommodation decreases by 2D or more compared to normal values, accommodation insufficiency is considered. There is a linkage between accommodation and convergence called accommodative convergence-to-accommodation (AC/A) which is closely related to exotropia. It was reported that the amount of accommodation required to maintain binocular fusion in patients with intermittent exotropia was greater than that of normal controls. In addition, pupil size and visual acuity are also factors that affect accommodation. In summary, the reduced accommodation amplitude, pupil dilation, and blurred near vision caused by atropine drops would affect the progression of intermittent exotropia and the ocular alignment after the surgery. In most cases, the reduced accommodation and convergence might induce exotropia, but in some patients, they may use more accommodative stimuli to compensate the insufficiency of accommodation, and there may be an increase in convergence or even esotropia. Taken together, due to the effect of atropine drops on pupil size, near visual acuity, and accommodation amplitude, the investigators hypothesize that atropine drops are likely to affect binocular vision and ocular alignment in patients with exotropia and exophoria.
This study intends to determine the number and percent of subjects initially diagnosed with divergence excess exotropia which would be reclassified as simulated divergence excess exotropia if tested after 24 hours of monocular occlusion (patching) or after prism adaptation for the distance angle.
The study aims to investigate ocular motor and sensory outcomes of two different strategies of lateral rectus recession; symmetric and asymmetric, in management of basic type intermittent exotropia with ocular dominance.