Active clinical trials for "Myopia"

The objective is to develop and evaluate an algorithm for implantable collamer lens (ICL) sizing that uses high frequency ultrasound biomicroscopy (UBM) for vertical placement.

This study intends to establish a registry cohort to enroll patients with high myopia to study the natural course of myopic optic neuropathy in Chinese adult population.

There was a prospective cohort observational study. Forty hyperopic children, 40 myopic children and 120 emmetropia children were randomly selected from grade 1 to grade 3, and were followed up every six months for 3 years. All patients received cycloplegic refraction examination, ocular biological test, binocular visual function test and a questionnaire related to daily eye habits. A multi-level and multi-dimensional data analysis model was constructed to explore the possible factors affecting the occurrence and development of myopia in children.

This is a non-interventional prospective, comparative study of white-to-white, corneal thickness, and anterior chamber depth measurements as taken on the Orbscan II compared to the IOL Master 700 (Zeiss), IOL Master 500 (Zeiss), Atlas 9000 (Zeiss), Lenstar 900 (Haag-Streit), Argos (Alcon), iTrace (Tracey), Pentacam (Oculus), and manual calipers.

The principle investigator is evaluating self-reported quality of vision and quality of life in physicians undergoing LASIK, SMILE and PRK surgery.

Glaucoma is the leading cause of irreversible blindness worldwide. Although the pathogenesis remains unclear, pathologic increase in intraocular pressure (IOP) due to blocked aqueous outflow through the trabecular-Schlemm canal is known to be an important risk factor, and reduction of IOP is the only clinically validated way to retard the progression of OAG. Ciliary muscle plays a central role in the trabecular meshwork-Schlemm canal outflow pathway. Clinical evidence suggests that ciliary muscle contraction stimulated by cholinergic receptor agonist and retraction of ciliary body position after cataract surgery can dilate the lumen of Schlemm canal and reduce IOP. Currently, Ultrasound biomicroscopy (UBM) can obtain two-dimensional images of the anterior segment using high-frequency Ultrasound transducers in medical imaging studies of the ciliary body - trabecular meshwork -Schlemm canal complex. UBM has better tissue penetration than Optical coherence tomography (OCT) and can image the ciliary body better, but it has a lower resolution (30um to 50um) and is poor at imaging tiny tissues such as trabecular meshwork and Schlemm canal. The latest swept-source OCT (SS-OCT) has faster image capture rate (1000000 A scans/SEC), stronger penetration and higher resolution (8um axial resolution and 20um transverse resolution). The structure and morphology of ciliary body-trabecular meshwork-Schlemm canal complex can be clearly photographed. The investigators intend to use CASIA2 to image the ciliary body-trabecular meshwork-Schlemm canal complex before and after administration of pilocarpine in healthy individuals and patients with glaucoma to assess the effect of pilocarpine on the anatomy of the ciliary body-trabecular meshwork-Schlemm canal complex.

This trial aims to test the effectiveness and practicality of study in the Bright Classrooms with skylight and artificial light renovation in reducing incident myopia in Chinese primary school children over three years, as compared to children studying in conventional classrooms.

To screen and identify sensitive biomarkers for high myopia via a robust, convenient, and cost-effective approach according to the association between high myopia and concentration of biomarkers in tear fluid, saliva and blood among adults and children.

The aim of this clinical trial is to compare the rate of myopic progression in children wearing aspheric (MyLens) and spherical/ toric ophthalmic lenses. The proposed lens design is an aspheric lens which is supposed to slow myopic progression in children by unique asphericity (proprietary information). Myopic progression is quantified by changes in axial length (AL) and cycloplegic refractive error (Rx) will be monitored for 6-12 months (6 months crossover) with double-masking. Peripheral refraction and ocular aberration will be evaluated.

The purpose of this study is to evaluate whether bifocal soft contact lenses (CLs) with low addition and nasally decentered optical zone are effective in controlling myopic progression in children. Visual manipulations induced by multifocal soft CLs with high addition have been shown to inhibit eye growth and myopia development in children by recent studies. Several theories have been proposed including alteration in peripheral defocus, reduced accommodation demand, alterations in binocular vision status and increased ocular higher order aberrations. However, those theories remain to be proven and the optical properties and performance of multifocal soft CLs have not been investigated in children.