Fundus damage in degenerative myopia
Introduction
Introduction to fundus damage in degenerative myopia Degenerative myopia is also known as pathologic myopia. After middle-aged patients, there are various degenerative degeneration in the fundus, called degenerative myopia. basic knowledge Sickness ratio: 0.1% Susceptible people: no specific people Mode of infection: non-infectious Complications: retinal detachment glaucoma cataract
Cause
Causes of fundus damage in degenerative myopia
(1) Causes of the disease
Genetic factors (30%):
Genetics has been identified as a major factor, and its genetic pattern is autosomal recessive, dominant and X-linked, and highly genetically heterogeneous. Polygenic genetic diseases are caused by the combination of genetic factors and environmental factors. Among them, the magnitude of the effect of genetic factors can be measured by heritability.
Acquired environmental factors (50%):
Acquired environment such as general health, living environment, personal habits, long-term use of close-eye work, etc., can contribute to the deepening of myopia. When a person is born, he is placed in social culture and influenced by social culture. The influence of culture on personality is accompanied by people's life.
(two) pathogenesis
The pathogenesis of this disease is extremely complicated, the scleral extension, especially the posterior scleral extension, thinning, is the key to the development of axial myopia to high myopia, but also the pathological basis of degenerative myopia, the extension of the sclera, different views, machinery Two theories of biology and biology, the latter in the recent study, some people believe that the mutation of one or some genes, resulting in the abnormal synthesis of scleral collagen, the cause of fundus degeneration, is also inconclusive, from the existing According to the data, it is likely that the early retinal senescence and choroidal dysfunction are caused by excessive scleral thinning.
Prevention
Prevention of fundus damage in degenerative myopia
1. Correcting the refractive error to achieve the best visual acuity at the lowest degree is most suitable, but sometimes the degree is too high, the patient is discomfort after wearing the lens, the appropriate reduction in the degree, maintaining good vision and acceptable for the patient to alleviate Excessive collection of visual fatigue, in addition to wearing glasses can also be corrected with contact lens to reduce the visual distortion and deformation caused by wearing glasses, can also expand the field of vision, radial keratotomy and the recent development of excimer lasers available To correct myopia, but the correction of high myopia remains to be further studied.
2. Visual hygiene education and good eye habits are extremely important, such as not reading when lying or walking, the lighting should be appropriate when doing close work, not too dark or too strong, the light is best from the top left, The sitting position should be correct, the head distance should not be too close, generally 33cm, not too long each time reading, generally 1 time lasting 45min ~ 1h is appropriate, at rest, eyes look far away, so that the eyes relax, can be used to make eye Health care to alleviate visual fatigue, these visual health education is especially important in adolescents.
Complication
Fundus damage complications of degenerative myopia Complications retinal detachment glaucoma cataract
1. Retinal detachment of liquefaction opacity of vitreous degeneration and retinal sac-like, lattice-like degeneration and other densities caused by degeneration, the two interact, leading to retinal detachment, clinically, a large part of rhegmatogenous retinal detachment is complicated by degenerative myopia .
2. Glaucoma myopia with glaucoma is about 14%, but due to the low hardness of the sclera of degenerative myopia, the measured intraocular pressure is low; the abnormality of the optic disc of myopia can not see the typical glaucoma cup-shaped depression; vision and visual field Changes are also easily blinded by myopia, so it is easy to miss the diagnosis.
3. Concurrent cataract is more common in middle-aged degenerative myopia, often manifested as brown opacity of the lens nucleus (nuclear cataract), can also be expressed as posterior capsule subcortical opacity, nuclear cataract due to increased refractive index of the lens to make myopia The degree is further deepened.
Symptom
Fundus damage symptoms of degenerative myopia common symptoms optic disc tilting black spot repeated bleeding myopia arc paint crack pattern
Vision loss, can not be satisfied with correction, the cause of vision loss, extensive retinal neuroepithelial atrophy, macular hemorrhage can cause sudden damage to vision, Fuchs plaques and macular atrophy plaques, resulting in irreversible visual deterioration, vitreous liquefaction and fly Mosquitoes, when the vitreous body is incompletely detached, the sensation of flashing may occur due to the traction of the retina.
1. Tigroid fundus (tigroid fundus) The entire fundus is slightly dark gray, and the choroid is diffusely atrophied. The blood vessels in the capillary layer and the middle vascular layer are reduced or disappeared. The blood vessels in the orange-red vascular layer are exposed, making the fundus appear as leopard skin. kind.
2. The optic disc tilt and myopic arc protrude from the posterior part of the high myopia wall, the optic nerve obliquely enters the ball, and the side of the optic disc (mostly the temporal side) shifts backward, causing the optic disc to lose its normal under the ophthalmoscope. Slightly vertical elliptical shape with a prominent vertical (or lateral, oblique) elliptical shape, even like a scorpion, with a crescent-shaped spot at the junction with its rearward displaced side, called a near-arc (conus, or stretch) Myopia arc, extensive conus), myopia arc to the side of the disk edge is slightly brown, the boundary is blurred, the upward traction arc of the ridge-like bulge (supertraction conus), the white of the extensional myopia arc, the sclera exposed, the outer side is light brown, is the pigment The epithelial layer disappears and the choroid is exposed. The outer boundary of the myopic arc is clear, but it is often connected with the atrophic area of the posterior pole. The nearsighted arc is located in the temporal side of the optic disc in most cases, and is also located on the upper or lower side of the optic disc. It is located on the nasal side or the lower side. The former is called the inversive myopia arc (inversive conus); the latter is called the Fuchs arcus (Fuchsconus). When the temporal side myopia arc is outward, upward and downward, it can be surrounded. Through the entire disc Wai, is peripapillary chorioretinal atrophy (circum papillary chorioretinal atrophy).
3. Macular hemorrhage and Fuchs macular hemorrhage are choroidal (new blood vessels or no neovascularization) bleeding, dark red, generally round, size and quantity are uncertain, more common in the macula or near the retinal blood vessels, repeated bleeding at the same location, It can cause hyperpigmentation and lead to the formation of Fuchs plaques.
The typical Fuchs plaque is round or elliptical, with a clear boundary and a slight uplift. The size is 0.3~1PD, black, sometimes bleeding can be seen at the edge of the dark spot. During the lesion, the dark spot can be enlarged or reduced, and the shape and color can also be It has changed and even broken down into scattered pigment spots, but it does not disappear completely.
Fuchs are seen in one or both eyes, and occasionally two dark spots are seen in the fundus.
4. Posterior pole atrophy and lacquer crack-like lesions of the choroidal retinal atrophy are white or yellow-white, round or map-like, varying in size and number, isolated or fused into large pieces, large patches of atrophy can be atrophied around the optic disc. It becomes a huge atrophy zone including the optic disc and the macula. The pigmentation is often found in the atrophic plaque or its margin. Sometimes residual choroidal vessels are visible. The macular atrophy and its vicinity are often seen as branched or reticular white or Yellow-white lines, lines and angioid streaks in the fundus are similar, wide and narrow, edges are not neat or jagged, similar to the old lacquer crack, so called lacquer crack lesion.
The lacquer crack-like damage occurs between the macula and the optic disc to the macula, which is caused by the atrophy of the pigment epithelium at the Bruch membrane, and the FFA is transparent.
5. Under the lens of macular degeneration and macular hole, the macula can be seen with a clear circular erythema with a diameter of 1/3 to 1/2 PD. The retina adjacent to the erythema is slightly grayish, with limited localization. There is a reflective ring, under the slit lamp microscope, if it is cystic degeneration, the light cut surface has a thin anterior capsule wall tangential line; if it is a split hole, the line is interrupted, and the tangential line of the outer wall of the split hole is misaligned with the surrounding retinal surface tangent line.
6. Posterior scleral grape swollen posterior sclera overextended, the posterior pole can undergo localized expansion, posterior staphyloma (posterior staphyloma), after the speckle, the grape swollen as a dish or crater-like depression, the edge can be a slope The shape can also be steep and steep. The retinal blood vessels crawl and crawl at the edges. The diopter at the bottom of the posterior grape edema is quite different from the edge. This difference in diopter is an important basis for the diagnosis of grape swollen.
7. Peripheral retinal cystic degeneration and lattice-like degeneration are common in the vicinity of the serrated edge. It is easy to find after binocular indirect ophthalmoscopy or three-sided microscopy. The cystic degeneration is round or round red in the retina. Against the background of gray-white atrophic lesions, the boundary is clear, around the atrophic lesions, and there are white lines formed by the white lines of the small blood vessels of the retinal terminals, which are called lattice degeneration, cystic degeneration, Form a retinal tear.
8. The vitreous liquefied vitreous gel body is depolymerized and liquefied, and some parts are concentrated into an off-white film or strip-like turbidity. Under the slit light microscope section inspection, the turbidity floats in the vitreous cavity, and the vitreous of the vitreous can cause the vitreous body. After detachment, it is more common to be separated later.
Examine
Examination of fundus damage in degenerative myopia
1. B-ultrasound can determine the length of the eye axis and understand the degree of axial myopia.
2. Computer and dilated optometry to understand the diopter.
3. When there is paint crack-like damage, fundus fluorescein angiography (FFA) can appear to see fluorescence; fluorescence obscuration can be seen in fundus hemorrhage.
4. Indocyanine green angiography can detect choroidal neovascularization.
Diagnosis
Diagnosis and diagnosis of fundus damage in degenerative myopia
According to the development process of myopia and the degree of myopia, it is not difficult to diagnose according to the typical changes of the fundus.
High myopia macular degeneration according to its high myopia history, typical leopard-like in the fundus, typical degenerative changes in the optic disc myopic arc plaque and macula, diagnosis is not difficult, but sometimes with ophthalmic toxoplasmosis, especially in the stationary phase or Congenital difference, although ocular toxoplasmosis is uveitis, but often no anterior inflammation, only the posterior uveal lesions, the predilection site is also located in the posterior pole, in the stationary phase or congenital can only be expressed as Old atrophic round lesions in the macular area, which may be accompanied by hyperpigmentation, similar to atrophic lesions of high myopia, but patients with toxoplasmosis have a history of contact with cats, dogs, etc., and skin and colony tests can be used to prove that Diagnostic treatment can also be used. Ocular toxoplasmosis can be treated with sulfonamide, minocycline, clindamycin and hormone therapy.
In the elderly, high myopia macular degeneration with choroidal neovascularization of the body scar, to distinguish with age-related macular degeneration, the former choroidal neovascular membrane is small and near the center, while the latter often accompanied by fundus arteriosclerosis or hypertension Sexual changes, in addition to discoid scars, there may be changes in early senile discoid lesions, such as single or fused drusen, pigmented epithelial serous or hemorrhagic detachment.
