indirect ophthalmoscopy

Indirect ophthalmoscopy Indirect ophthalmoscope can magnify the fundus by 4.5 times. It is seen as an inverted real image. The range of seeing is large, and it can reach 25°~60° at a time. It has strong stereoscopic effect, wide depth of field, and retinal detachment. Wrinkles and other lesions that are not on the same plane of the fundus can be seen at the same time. When examining the peripheral fundus, it is best to enlarge the pupil, and the patient will turn the eyeball to one side, and the examiner should also tilt the head properly. Basic Information Specialist Category: Ophthalmic Examination Category: Other Inspections Applicable gender: whether men and women apply fasting: not fasting Tips: When checking: When checking the peripheral fundus, it is best to enlarge the pupil, and the patient will turn the eyeball to one side, and the examiner should also tilt the head properly. Normal value The optic disc is located about 3 to 4 mm on the nose side of the eyeball, and has a diameter of about 1.5 mm. It is oval in shape and reddish in color, but the color on the temporal side is slightly light. The blood vessel branches of the blood vessels do not coincide with each other. The arteries are bright red, the tube diameter is thin and straight, and there is a clear reflection strip in the center, which is about 1/3 of the tube diameter. The veins are dark red, the tube diameter is slightly thicker and more curved, and the reflection of the lumen is darker and smaller. The ratio of arteries to veins is approximately 34 or 23. In the optic disc, venous pulsations are sometimes seen, which is normal. The macula is located slightly below the optic disc, about 2 disc diameters (PD) from the optic disc, and the range is about 1PD. It is usually a circular area, which is slightly darker than other parts of the fundus and dark red. The general form of the fundus is transparent. The entire fundus is diffuse orange-red under the illumination of the ophthalmoscope. This is due to the pigmentation of the retinal pigment epithelium and choroid and the color of the blood in the choroidal capillaries. Clinical significance Abnormal results If the artery is pulsating, it is a pathological phenomenon. There are many choroidal pigments that accumulate between the blood vessels, that is, a stripe of red and brown, called leopard-like fundus. The person who needs to be examined is ametropia or a person whose refractive medium is destroyed. Precautions Taboo before check: emotional stress. Requirements for examination: When inspecting the peripheral fundus, it is best to enlarge the pupil. The patient will turn the eyeball to one side, and the examiner should also tilt the head properly. Inspection process During the examination, the subject took a sitting position or a lying position, and the inspection distance was about 50 cm. The examineor used a lens with a +13D--28D on the thumb and index finger (in order to improve the image quality, an aspherical lens is often used), with the ring finger and the little finger. Relying on the forehead of the subject, and lifting the upper jaw, the lens moves within the range of 4 to 9 cm in front of the subject until the fundus image is seen. Not suitable for the crowd Inappropriate people: glaucoma patients.