View clinical trials related to High Myopia.
Filter by:This study aims to investigate the impact of depth of field differences between the use of the 3D imaging system (NGENUITY® 3D Visualization System, Alcon, TX, USA) and conventional optical microscope in cataract surgery for highly myopic patients on intraoperative parameters and outcomes.
The purpose of this clinical study is to confirm the effectiveness and safety of low-level monochromatic red-light for high myopia control in adults
The purpose of this clinical trial is to investigate the incidence and magnitude of axial length shortening after repeated low-level red-light therapy in high myopia children and teenagers.
The purpose of this clinical trial is to confirm the incidence and magnitude of axial length shortening after RLRL therapy in Chinese high myopia children and teenagers.
The rigid scleral contact lens with optical multi-focal design adopted in this study can focus the light in part of the optical area on the front of the retina to form myopic defocus, in order to delay the axial changes in children and adolescents with ultra-high myopia. In this study, RGP was used as a control, and a multicenter, randomized, controlled trial was conducted to verify the safety and effectiveness of multifocal scleral contact lenses for the correction of ultra-high myopia in children and adolescents.
The IOL-capsular complex is formed after cataract surgery and intraocular lens (IOL) implantation.Early postoperative mechanical wrapping of the anterior and posterior capsules plays a significant role in preventing IOL decentration and tilt, as well as formation of the IOL-capsular complex which reduces the incidence of posterior cataract opacity. Capsular tension rings were first introduced in the early 1990s for loosening and tightening the lens bag and maintaining the equatorial contour of the bag after cataract surgery.Today, capsular tension rings of many different designs are in use.The capsular tension rings can be used in eyes with fragile and split zonular fibers, as well as pseudoexfoliation, high myopia, Marfan syndrome, mature cataract and lens subluxation.The capsular tension ring reduces the incidence of decentration and tilt of the IOL by reducing capsular contraction. In addition, multi-focus IOL implantation combine with capsular tension ring result in smaller high-order aberrations in our eyes compared to cataract surgery with multi-focus IOL implantation alone.For patients with high myopia, they often have a longer axial length and a larger capsule diameter, which reduces the rotational stability of the IOL and may lead to tilt ,decentration and displacement of IOL.Currently, there is no literature guidance to compare the results of cataract surgery combined with or without capsular tension ring implantation in patients with high myopia.Our hospital has Swept-source Optical Coherence Tomography ( SS-OCT,Casia2, TOMEY, Japan), which can accurately photograph the process of IOL capsule bending and the changes of lens position after cataract surgery. SS-OCT can be used to evaluate the influence of capsular tension ring on the dynamic changes of IOL-capsular complex in patients with high myopia after cataract surgery.
To evaluate IOL position, clinical outcome of PanOptix in high myopic cataract patients
The prevalence of myopia is seemingly increasing, and it is one of the major causes of blindness. High myopia is defined as a refractive error with spherical equivalent exceeding -6 diopters and/or the axial length longer than 26.5 mm. The global prevalence of high myopia is estimated to rise from 2.7% of the world population in 2010 to 9.8% of the world population in 2050. High myopia is characterized by axial length elongation, and consequent stretching of the posterior eye wall (thin retina and choroid). There are many complications of high myopia such as posterior staphyloma, lacquer cracks and myopic choroidal neovascularization. Normal labour may cause the ocular complication in pregnant women with high myopia, such as macular hemorrhage. Therefore, the caesarean section with epidural anesthesia is recommended. Moreover, there is no standard screening guideline for pregnant women with high myopia.
In recent decade, a major improvement in vitreoretinal surgery was the use of small gauge surgical systems that improved the safety of vitrectomy and also reduced the surgical time. However, there were still some concerns regarding small gauge vitrectomy system, especially 27-gauge system, in the stability of its instruments and the efficacy of removing vitreous during surgery. Although there were some studies that had reported the surgical outcomes of 27G vitrectomy system, none had focused on patients with high myopia. The highly myopic patients usually had thinner sclera, which was a risk factor for wound leakage after sutureless vitrectomy, they also had longer axial length which would make the surgical procedure more difficult especially in macular surgery. Based on previous clinical finding, gas leakage was 36.4% in 25G , while 27G sclerotomy showing less leakage comparing to larger gauge sclerotomy, the investigators believe 27G may have its clinical advantages in overcoming the thinner sclera of high myopia, and show the superiority of leakage control. Hypothesis: The 27G vitrectomy system has lower sclerotomy wound leakage rate compared with 25G system
evaluation of the accuracy of iol power in high myopia using different biometry formula & iol master