polycythemia retinopathy
Introduction
Introduction to erythrocytosis retinopathy Polycythemia (polycythemia) is a blood disease in which blood erythrocytosis and hemoglobin increase, and blood volume increases. When the number of red blood cells exceeds 6 million to 6.3 million/mm3, hemoglobin exceeds 110 g/L or more, and fundus symptoms can occur. basic knowledge The proportion of illness: 0.003%-0.009% Susceptible people: no specific population Mode of infection: non-infectious Complications: intracranial tumors
Cause
Etiology of polycythemia retinopathy
(1) Causes of the disease
Increased erythrocytosis caused by various causes.
(two) pathogenesis
Any kind of polycythemia, when the number of red blood cells is more than 8×1012/L, and the hemoglobin is more than 125%, the same pathogenesis can be accompanied by the same fundus changes. The important changes in the fundus are as follows:
1. Due to the increase in blood volume, all blood vessels in the fundus will not only expand but also lengthen. The retinal vessels are confined to the retina, and the growing blood vessels become distorted. Among them, the veins are more prominent, the veins are highly dilated, and the blood column is dark purple. Or the mature purple grape color, the arterial tube also expands, and the reduced blood hemoglobin, the blood column also loses the original bright red, becomes a dark red similar to the normal vein, and the retinal vascular tortuous expansion is not only seen in the large branch, but also extends to the distal end. Small branches, under the ophthalmoscope, it seems that the blood vessels appear to be more than usual. The diameter of the veins is sometimes uneven, and the severe ones are like sausages.
2. Due to the increase in the amount of red blood cells and hemoglobin, high blood viscosity and blood stasis, the entire fundus is changed from normal orange to purple, that is, retinal hair.
3. When the blood vessels are generally dilated and the blood is not obstructed, the retina has no other complications except for the hair; if the blood vessel wall itself changes, or the blood viscosity is particularly serious, the retinal hemorrhage is caused by the circulation disorder, and even Causes the trunk or branch of the central retinal vein to block.
4. In the case of polycythemia, normal or slightly reddened optic disc, congestion and edema may occur, and optic disc edema may occur. Like other blood diseases or other diseases, most of them are caused by elevated intracranial pressure, except for red blood cells. Increased symptoms due to high cerebral vascular dilatation and cerebral edema, or cerebral hemorrhage can increase intracranial pressure, can not be ignored may have simultaneous intracranial lesions, especially to guard against hemangioblastoma (hemangioblastoma), such intracranial Pressure damage can sometimes lead to relative polycythemia. The mechanism of intracranial tumors producing polycythemia is still unclear, but the polycythemia and optic disc edema disappear after tumor resection, indicating the causal relationship between them (Figure 1 ).
Prevention
Red blood cell retinopathy prevention
Retinal cyanosis caused by polycythemia does not have much effect on vision. When there is bleeding, there are different degrees of obstacles due to the number and location of bleeding. If the patient complains of blurred vision or hemianopia, but the fundus changes can not explain the cause, visual path damage, such as intracranial complications, cerebral hemorrhage, cerebral thrombosis, etc., should be considered.
Complication
Complications of erythrocytosis retinopathy Complications intracranial tumors
Central retinal vein or branch obstruction, retinal hemorrhage and exudation, intracranial tumors, etc.
Symptom
Symptoms of retinopathy of polycythemia common symptoms fatigue visual impairment fundus changes retinal hemorrhage insomnia red blood cell dizziness visual field defect tinnitus illusion
Eye symptoms
Vision can be normal or have a short-term blur, or a transient black sputum, can appear fear of light, visual fatigue, flash illusion, flying mosquito illusion, night vision disorder, black or dark spots in front of the eye, visual field defects and double vision, etc. Symptoms may be accompanied by changes in the fundus or no changes in the fundus. If there is no change in the fundus and the above symptoms, consideration may be given to post-balloon lesions or intracranial lesions such as cerebral hemorrhage or thrombosis in the brain.
2. Fundus changes
(1) optic disc change: there may be blurred disc border, congestion, surface telangiectasia caused by physiological depression, sometimes optic disc edema, up to 2 ~ 3 diopter, the disease caused by optic disc edema, the primary accounted for 3.2% Secondary infection accounted for 11.6%. The cause of optic disc edema may be increased blood viscosity, slow blood flow, resulting in blockage of small vessels in the optic disc. The occurrence and extent of optic disc changes are directly proportional to the increase in the number of red blood cells.
(2) Retinal vascular changes: retinal arteries generally have no obvious changes, 11% of cases may have arterial spasm, retinal vein changes are the most prominent and most common signs of this disease, accounting for 78.5% of the disease, and with red blood cells The number increases and increases. For example, when the number of red blood cells is 6 million to 6.5 million/mm3, the venous filling only accounts for 56.4%. When the number of red blood cells increases to more than 8 million/mm3, the venous filling is 100%, and the retinal vein is highly distorted and expanded. It is purple-red or purple-black, especially at the intersection of arteries and veins. The diameter of the vein is uneven, and the veins at the distal end are enlarged. It can be beaded or sausage-like. The color is ripe purple grape color, and the diameter of the vein is thicker than the original tube. The diameter is 2 to 3 times, and the ratio of arteries and veins can be 2:6. In severe cases, blood flow is blocked, and central retinal vein occlusion or branch obstruction can occur. The capillaries are filled and expanded, as if the entire retina is full of blood vessels, and the choroidal vessels are also dilated. Filling and darkening of the color, the entire fundus is blue-purple, called cyanosis retinae.
(3) Retinal hemorrhage and exudation: relatively rare, accounting for 9%, bleeding can be small spots or flaky, mostly shallow layer of bleeding, occasionally bleeding into the vitreous, exudation is more rare.
3. Other changes in the eye
In addition to changes in the fundus, the eyelids may be purplish red, the vasoconjunctival vasodilatation is filled, and small bleeding points are visible. The conjunctival vasodilatation is filled, especially in the peripheral blood vessels, which may spirally expand and have scattered small bleeding points, shallow layers. The scleral vessels are also dilated, the iris vessels are dilated and filled, causing the iris tissue to thicken, and the iris crypts and folds in the ciliary region become shallow or flattened.
4. Whole body performance
The patient has a sputum face, especially the lips, the tongue is more obvious, the mucous membranes and limbs are also sputum, the spleen is swollen due to congestion, the patient may have headache, dizziness, tinnitus, numbness of hands and feet, insomnia and other symptoms, laboratory tests, the number of red blood cells is significantly increased If more than 6.5 million / mm3 can be diagnosed, there have been reports of up to 10 million / mm3, hemoglobin increased, platelet and white blood cell count also increased.
Examine
Examination of polycythemia retinopathy
Blood routine examinations determine the number of red blood cells and hemoglobin levels, and blood rheology tests determine blood viscosity.
Fundus examination to confirm the fundus lesions, head CT scan or MRI examination to exclude intracranial pressure caused by intracranial space-occupying lesions and bleeding.
Diagnosis
Diagnosis and diagnosis of polycythemia retinopathy
According to the blood test results and fundus performance, the diagnosis of this disease is not difficult.
