How to use the three-mirror fundus examination?

Nowadays, it is the age of the Internet. Whether it is the elderly, the young, or the children, they all like to play with computers, mobile phones, tablets and other electronic products. As the elderly grow older, most of them will have some eye diseases. If they often look at the mobile phone, it will cause certain damage to the eyes. The three-mirror fundus examination can effectively check some eye diseases, allowing everyone to discover the disease and treat it symptomatically.

There are three commonly used methods for fundus examination: direct ophthalmoscopy, indirect ophthalmoscopy, and three-mirror ophthalmoscopy. The fundus examinations of the "indirect ophthalmoscope" and the "three-mirror ophthalmoscope" are more detailed and comprehensive. The advantages of these two fundus scopes are that they have a wide range of fundus observation, can observe the serrated edge of the retina, and have brighter lighting and a stronger three-dimensional effect. Compared with the two, the "three-mirror" examination effect is better than the "indirect ophthalmoscopy".

The function of the three reflectors of the "three-mirror" is to observe the peripheral retina. The angles formed by the three reflectors and the front surface are 59°, 67°, and 75°. The steeper the mirror slope (the smaller the angle), the more you can see the peripheral part of the fundus. Before use, drop viscoelastic agent to protect the cornea into the central spherical mirror of the "three-sided mirror", then put it into the eye socket and contact it with the cornea. The median spherical mirror of the "three-sided mirror" can only see the posterior pole of the fundus, namely the optic disc area (optic nerve) and the macular area. The "three-sided mirror" needs to be used in conjunction with the "slit lamp microscope" to observe the fundus. During the examination, the angle between the light source of the slit lamp and the microscope is about 15° to 30°. The image of the fundus seen by the doctor is opposite to the actual position in the up, down, left and right directions. When examining peripheral retinal lesions, if the range is not enough, a "scleral compressor" can also be pressed against the outside of the sclera to assist in observing the peripheral retina. After the inspection, the results should be recorded promptly and illustrated with drawings. Some more formal hospitals will have "indirect ophthalmoscopes" and "three-sided mirrors", but many ophthalmologists do not master them, or are unwilling to use them because they find it troublesome. They simply use "direct ophthalmoscopes" to observe the fundus and call it a day. They do not realize that they will miss many tiny fundus lesions, which will pose a hidden danger to myopia surgery itself and future fundus and retinal safety.

(2) Look for retinal holes in retinal detachment

(3) Differentiation between retinal hemorrhages and retinal tears

(4) Differentiation of macular lesions (such as lamellar holes, holes, hemorrhages, and cystic degeneration)

(5) Diagnosis and differentiation of vitreous lesions (turbidity, concentration, liquefaction, proliferation, and fibrous membrane formation)

(6) Lesion localization