Low vision is defined as a visual impairment that cannot be improved by surgery, medication or general optometry, mainly consisting of reduced visual acuity and reduced visual field, where the best corrected visual acuity in the better eye is less than 0.3 and equal to or better than 0.05 in both eyes. The new definition refers to patients with visual impairment even after treatment or standard refractive correction, whose visual acuity is less than 0.3 to light perception, or whose visual field radius is less than 10 degrees.
According to the results of our survey, the first cause of low vision is high myopia, the second is optic nerve atrophy, the third is congenital microcornea and microphthalmia, the fourth is primary retinitis pigmentosa, the fifth is congenital cataract postoperative aphakia, followed by macular degeneration, glaucoma, congenital nystagmus, age-related cataract and congenital cataract.
New Ophthalmic Technology in Ophthalmology
The main cause of low vision in China is high myopia. The causes of high myopia include genetic factors and environmental factors, and we can still intervene early in the latter at present. With the increasing number of myopia and low vision patients, the issue of vision health has become urgent. The new technical level of optometry in our hospital has developed considerably, equipped with examination equipment, professional optometrists, dispensing center and myopia control center, which is in the leading position in the city and surrounding areas. Here are a few medical knowledge that our hospital has matured to carry out and is closely related to low vision, welcome to visit our hospital.
ICL – Posterior Chamber IOL for Crystalline Eyes Treatment of High Myopia
ICL is currently considered to be the latest technology that can replace LASIK, PRK and other cutting procedures for refractive correction, and is one of the newest and safest methods for correcting high myopia, which has been accepted and used by ophthalmologists worldwide. It can be used to correct large degrees of myopia, hyperopia and astigmatism without disrupting corneal tissue and without the need for post-surgical sutures. It also allows for predictable refractive correction and excellent visual quality. In particular, it is significantly more effective than excimer laser surgery in treating high myopia of more than 800 degrees and up to 2000 degrees. ICL is made of a small amount of purified collagen polymerized with good compatibility and no adverse reactions in the eye. the advantage of ICL is the high degree of correction and can be removed if uncomfortable. For patients with ultra-high myopia and thin corneas, refractive lens is significantly superior to excimer laser. Therefore, it is now internationally recognized that refractive lens implantation is preferred over excimer laser for patients with ultra-high myopia because the cornea has become significantly thinner to the limit after excimer laser for these patients, and surgical complications are on the high side.
RGP – Rigid oxygen permeable corneal contact lens to control myopia progression
RGP is an oxygen permeable rigid contact lens that increases the amount of oxygen passing through the lens. Compared to soft contact lenses, it improves oxygen permeability while maintaining the strength of the material, and has good wettability and anti-sedimentation properties. It has been clinically verified and affirmed at home and abroad for the control and correction treatment effect of youth true myopia and cone cornea. In recent years, due to the synthesis and application of good biocompatible polymer materials, rigid corneal contact lenses have been rapidly popularized worldwide. Currently, RGP has been widely used in Japan, and according to statistics, about 10% (11 million people) of the Japanese population wear contact lenses, of which 40-50% wear RGP. It is safer, less likely to cause hypoxia and dry eye, and does not cause changes in the number of corneal endothelial cells.
In addition, RGP is highly regarded by ophthalmologists worldwide because of its unique advantages.
1, good molding, not easy to deformation, high quality of optical correction. Especially for some patients with high myopia and astigmatism, the correction effect is better. For irregular astigmatism of cornea caused by various reasons, such as: cone cornea, after keratoconus surgery, after trauma, etc., it is the only correction method that can effectively improve visual acuity.
2. It has good biocompatibility. Even long-term wear will not cause corneal hypertrophy and edema. It also has a certain maintenance effect on the health of the cornea.
3. Anti-precipitation, RGP lenses can be worn continuously without daily removal and cleaning, and can be worn day and night. It is easy to care for and the lenses have a long life span, as long as attention is paid to their correct use, they generally have a life span of 2-3 years, from this point of view it is also very economical.
4, high definition, can control myopia, astigmatism deepening, especially the youth myopia can be slowed down by it, early cone cornea and cone corneal tendency to have treatment and slowing effect, which is unmatched by traditional soft lenses.
MCT-Digital Keratomileusis Correction for Youth Myopia
MCT is a new type of youth myopia prevention and treatment lens that uses what is commonly referred to as RGP material, or “breathable rigid material”. It is a kind of rigid keratoplasty lens that is designed through a physical shaping method and a reasonable and programmed special design. The purpose of wearing the lenses at night is to make the myopic cornea become mildly myopic or not myopic, and during the daytime, the adolescent’s myopia is reduced or disappeared because of the change in the shape of the cornea, and if used for a long time, myopia can be controlled to a certain extent, and the effect of prevention and treatment of myopia can be achieved.
At present, this is a new technology that has been researched abroad to treat and prevent the aggravation of myopia, especially for controlling myopia in teenagers. It is suitable for children and adolescents who are not effective in using frame glasses, whose myopia is growing rapidly, whose myopia and astigmatism are high, whose parents have high myopia, whose children have a tendency to inherit it, and whose parents do not want their children to wear ordinary glasses.
MCT advantages.
1, the only personalized custom, fitting professional, simple and safe, comfortable and convenient; simple care method, long service life;
2, no trial, advanced inspection equipment to measure the corneal data, custom lenses fine and accurate; comprehensive visual effect is far better than frame glasses, traditional soft lenses, traditional OK lenses; vision recovery fast, clear vision;
3, in the wearing of the same time, can effectively control the youth myopia deepening, but also can prevent myopia;
4, special high oxygen-permeable materials greater than 100DK, the eyes easily breathe natural;
5, the lens full anastomosis design, the edge of the special curvature microprocessing tear exchange freely and easily;
6, good reversibility, no surgical trauma, safety, convenience, good results;
7, no glare, diffraction, visual fatigue and other side effects, not only good vision, and see things comfortably, lasting.
The fitting process and follow-up requirements of RGP and MCT are very strict and scientific, and a professional team is needed to ensure their safety and effectiveness.