high myopia
Introduction
Introduction to high myopia High myopia refers to ametropia with myopia degree greater than 400-600 degrees, with degenerative changes such as axial lengthening, retinal retina and choroidal atrophy. High myopia in China is autosomal recessive inheritance. It manifests as myopia in the school age (pre-) period, the progressive increase in myopia, and the retinal choroidal lesions in the fundus are increasing year by year, resulting in many serious complications. basic knowledge The proportion of sickness: 0.1% - 0.25% Susceptible people: no specific population Mode of infection: non-infectious Complications: glaucoma cataract
Cause
High myopia cause
The cause of high myopia is not known. Pathological myopia occurs in a large genetic relationship. The acquired environment plays an important role in the pathogenesis of myopia.
Prevention
High myopia prevention
Prevention of high myopia development methods: continuous short-distance use of the eye should not be too long. Actively participate in outdoor activities. Reasonable adjustment - set training. Usually, you must ensure adequate sleep, work and rest, balanced diet, and reasonable nutrition. Special attention should be paid to the proper use of the eye, the selection of appropriate work, to avoid excessive use of the eye and poor visual stimulation. Measures that may slow or terminate the development of myopia, including optician (double focus lens, high oxygen permeability rigid contact lens), drugs, surgery, etc.
Complication
High myopia complications Complications glaucoma cataract
1, vitreous lesions
As the axial length is extended, the vitreous cavity is enlarged, which promotes the progressive degeneration of the vitreous, thereby successively causing liquefaction, turbidity and detachment.
2, cataract
Due to abnormalities such as intraocular blood circulation disorders and tissue degeneration, the lens can also be affected, mainly due to lens opacity.
3, glaucoma
The combined open angle glaucoma is six to eight times more than normal eyes, and the proportion of normal tension glaucoma and suspected glaucoma is also significantly higher than other people.
4, macular degeneration
Common macular hemorrhage, macular degeneration, macular hole.
5, retinal shedding
It is a common complication of high myopia, with an incidence of eight times or ten times that of other people. Among primary or rhegmatogenous retinal detachments, the proportion of myopia can be as high as 70% or more.
6, posterior scleral staphyloma (posterior scleral spaphylomn) degenerative myopia due to the eyeball from the equator to the posterior extension, the posterior pole sclera is significantly thinner, a localized expansion, under the effect of intraocular pressure, sclera bulging, and Forming posterior scleral staphyloma of varying sizes. Its occurrence is clearly related to the level of diopter and the length of the eye.
7, amblyopia
8, strabismus
Due to abnormal regulation and aggregation function and imbalance of relationship, it is often accompanied by recessive external oblique or dominant external oblique.
Symptom
High myopia symptoms Common symptoms Visual acuity often foggy blurred eyeballs prominent visual impairment eye shadow
1. Vision loss.
2, myopia development speed: different from simple myopia, some high myopia even after adulthood, myopia continues to develop, it is also known as progressive myopia.
3, eyeball protrusion: high myopia is mostly axial, the eyeball is obviously longer, the anterior chamber is deeper, the ciliary muscle is atrophy, and some people's eyeballs protrude outward.
4, dark adaptation function: the retinal pigment epithelial cells develop lesions, affecting the photochemical reaction process of visual cells.
5, the front of the shadow: high myopia can cause vitreous degeneration, liquefaction, posterior vitreous detachment.
Examine
High myopia examination
1, retinoscopy optometry, ciliary muscle paralysis optometry.
2, flattening tonometer to measure intraocular pressure, for high myopia, Schiotz tonometer measured value is lower than the actual intraocular pressure.
3, dilated with indirect ophthalmoscope to check the fundus: looking for retinal tears and detachment.
4, slit lamp combined with three-sided mirror or 60D, 90D lens to check the macular area, looking for subchoroidal neovascularization.
5, feasible fundus fluorescein angiography.
6. Optical coherence tomography (OCT) can show the detachment of the macula above the posterior scleral staphyloma.
Diagnosis
High myopia diagnosis
Differential diagnosis:
1. Age-related macular degeneration (ARMD)
Choroidal neovascularization (CNV) can occur, and the macular area behaves like high myopia, but with typical drusen, without the above-mentioned myopic optic disc changes.
2, ocular histoplasmosis
There is atrophy around the optic disc and there is a risk of choroidal neovascularization. A pigmented ring separates the optic disc from the atrophy around the optic disc, while the myopic arc separates the atrophic region from the adjacent retina. The entire fundus is scattered in a circular chiseled choroidal scar.
3, the disc tilt
The irregular optic disc incorporates an arcuate sclera that tends to tilt downwardly below the nose. When the optic disc is emitted, the shape of the blood vessel is irregular (the position is opposite to normal), and the fundus has an expansion toward the oblique direction (below the nose). Many patients have myopia and astigmatism, no chorioretinal degeneration or lacquer cracks.
4, cerebral choroidal retinal atrophy
rare. The multiple, well-defined choroidal retinal atrophy in the retina of the retina that occurs in childhood gradually merges and affects most of the fundus. Elevated blood ornithine levels. Patients often have high myopia. It is autosomal recessive.
5, ocular toxoplasmosis
Clearly bordered choroidal scar, no typical choroidal neovascularization (CNV), active period of retinitis and vitreitis.
