View clinical trials related to High Myopia.
Filter by: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
Currently, whether and when intraocular pressure (IOP) lowering medication should be used in glaucoma suspects with high myopia (HM) is still a dilemma. Randomized trials are required to evaluate whether IOP lowering influences the incidence of glaucoma suspect progression in HM eyes.
Small Incision Lenticule Extraction (SMILE) was introduced in 2011 using the VISUMAX femtosecond laser (Carl Zeiss Meditec, Jena, Germany). It is designed for correction of myopia and myopic astigmatism. It involves the creation of a corneal tissue disk called lenticule and its extraction through a minimally invasive incision, utilizing only a femtosecond laser. This enables rapid visual recovery with very little discomfort to the patient. This observational case series monitors visual and refractive outcomes of myopic correction for more than -7.75 D. It is to - gather long-term results and refractive stability - detect rare complications or side-effects - evaluate the efficacy in a large number of patients
This project aims to investigate/examine high myopic subjects on full correction ortho-k (using Topaz ortho-k lenses for high myopia) compared to subjects undergoing partial reduction ortho-k and their relationship with myopia and myopic progression.
1.1 Research objectives A．To observe the fundus changes in the posterior pole (morphology, thickness, asymmetry, blood flow density, etc) with the myopia progression. B．To observe morphological changes in choroid and peripheral region of retina with myopia progression. C. To observe changes of visual function (contrast sensitivity, Microperimetry, etc) with myopia progression. D. To detect the susceptibility genes related to high myopia and myopic fundus changes; to test the levels of Vitamin D, riboflavin, transforming growth factor（TGF）, insulin-like growth factor（IGF）, fibroblast growth factor（FGF）, etc. E. To observe the changes of living quality, psychology, behavior and social activities of high myopic children. 1.2 Research design Prospective cohort study. After completing the baseline survey, the planned follow-up frequency is once a year. 1.3 Research cycle 2018.06~2038.06 (at least). 1.4 Expected results A． Registration completed a study of high myopia research for children and adolescents covering around 3,000 people; B． Establish a database information management system and workflow SOP（standard operating procedure）file for the study of high myopia registration in children and adolescents; C． Further clarify the changes in the retinal, choroidal and scleral tissue structures, blood flow density, etc. in the macular area and the optic disc; D． Revealing the changes of the retina, choroid and other tissues in the peripheral area with the progression of myopia; E． To clarify the relationship between changes in the fundus structure and changes in visual function in the posterior pole; F． Further clarify the etiology and pathogenesis of high myopia, pathological myopia and myopic fundus lesions, and identify the relationship between high myopia and pathological myopia; G． From the perspectives of society, behavior and psychology, the effects of high myopia and pathological myopia on children and adolescents will be fully demonstrated. 2. Research object 2.1 General characteristics of the research object Based on the refraction development archive system that has been constructed in Shanghai, the list of children and adolescents with high myopia was selected from the database of children's refractive development archives information in Shanghai. Children of different ages with high myopia must meet the following conditions: 1. 4-5 years old, equivalent spherical error(SE) ≤ -4.0 diopter(D）; 2. 6-8 years old, equivalent spherical error(SE) ≤ -6.0 diopter(D）; 3. 9-18 years old, equivalent spherical error(SE) ≤ -8.0 diopter(D）. 2.2 Sample size A total of 1.25 million children and adolescents are currently registered, 4,006 (0.32%) of which meet the entry requirements. Among the 4~5 year olds, there are 815 people with SE≤-4D; 842 people with SE≤-6 D among the 6~8 year olds; 2349 people with SE≤-8D among the people aged 9 and over . Taking into account the 50% non-response and the proportion of the exclusion, the initial registration number is about 2,000. 2.3 Source of study object Children and adolescents who meet the inclusion criteria in the Shanghai Children's Refractive Development Archives Information Database System.
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.
The study aims to observe the relationship between the changes of ocular structure parameters and pathological changes among children and adolescents with high myopia. Environmental factors and family history will also be collected to explore their impacts on high myopia progression.
The investigators aimed to investigate TGFB1 and LAMA1 gene polymorphisms in children with high myopia in order to determine the genetic basis of large myopic shifts causing severe visual impairment and complications. Seventy-four children with high myopia (≥6 diopters [D]; study group) and 77 emmetropic children (±0.5D; control group) were included. Genetic and polymorphism analyses were performed in the Medical Genetics Laboratory using DNA purified from the patients' blood samples.
High myopia retinopathy has become the first cause of irreversible blindness and severe visual impairment in Chinese adults, in order to avoid the blind and visual impairment caused by high myopia retinopathy, it is very necessary to research the mechanism of early visual impairment to prevent and control damages. Our recent research found that the decreasing of macular retina vascular density and subfoveal choroidal thickness, the increasing of Beta Zone area in optic atrophy and the rising of glycosylated hemoglobin in high myopia patients were significantly related to visual impairment, which suggested that the source of visual impairment was the abnormal structure changes surrounding optic and fovea, but so far there is no related study. We will conduct a 5 years prospective cohort study in the population of 2420 high myopia and controls which have established in college student population, working population and aged more than 50 years old population, using the latest OCT-A and SS-OCT to measure macular retina vascular density, subfoveal choroidal thickness, Beta Zone area in optic atrophy, combined with the semiparametric mixed effects model, we will analysis the prediction index between fundus structure parameters, blood biochemical index and individual characteristics prediction to explore the public health management mode of early prevention and treatment during high myopia population.
Full-thickness macular Hole associated with macular detachment is a one of the maculopathies of high myopia. There is controversy in the primary treatment for this situation. This study will compare the effects of macular buckling versus vitrectomy in a cohort of highly myopic eyes with this situation.