blue visual field defect
Introduction
Introduction "Field of view" is also called "field of view." When the eye is fixed to gaze at a point (or through the instrument), the range of space that can be seen is greater than that of the monocular field of view: the field of view for each color is small, the green field of view is the smallest, and the red field is smaller. Large, blue is larger, white is the largest. If the blue-controlled tissue in the eye is abnormal, the visual field defect of the color will appear, and the blue visual field defect is also the reason. The cause of the visual field defect is considered to be high intraocular pressure directly. Compression of optic nerve fibers or oppression of the supply of blood vessels around the optic papilla, resulting in nerve fiber bundles caused by blood supply disorders.
Cause
Cause
The cause of visual field defect is considered to be caused by high intraocular pressure directly compressing the optic nerve fibers or oppressing the blood vessels around the optic papilla, resulting in blood supply to the nerve fiber bundle.
Examine
an examination
Related inspection
Ultrasound examination of the eyeball and eyelid and CT examination of the temporal region
Clinical visual inspection is very common and is important for the diagnosis of ocular and systemic diseases.
Diagnosis
Differential diagnosis
1. The field of view of a normal person, according to the visual field of different colors, the range of the field of view is also different. Generally, the eyesight is 33 cm from the eye mark. For inspection, the normal field of view is checked with a white visual mark: 55° above and 60° inside. 70° below, 100° outside, the field of view is reduced by blue, red and green optotypes, each decreasing by 10°, and the corresponding position of the optic nipple in the field of view is a small blind zone, called the physiological blind spot.
2, the density can not see the target in the blind area, called the "absolute" defect, if you can see the target, but the color has become darker, which is called "relative" defect. When participating in cellular damage caused by visual photochemical changes, it is easy to detect the defect with yellow or blue, and when the tissue lesion is visually impaired, a large defect can be obtained by examining with red or green. There is a certain gap between the white field of view and the color field material. For example, red and white are about 10 to 20 degrees apart. Those who maintain this gap are called proportional, otherwise they are called disproportionate. A proportional visual field defect indicates that the condition is relatively static, disproportionately indicating that the condition is progressing. Some rickets have a white field of view that intersects the red field of view.
