Li Jinrong, Zhongshan Eye Hospital: How do ophthalmologists judge the degree of myopia?
When judging the degree of myopia of patients, ophthalmologists need to consider multiple factors, including visual acuity, eye length, refractive status, etc. The following will elaborate on how ophthalmologists judge the degree of myopia from four aspects.
1. Measurement of vision
The first step is to measure the patient's vision. Snellen vision chart is usually used to let the patient stand at a certain distance and read the letters or symbols that can be seen clearly. In this way, the vision of the patient can be preliminarily understood and whether there is myopia can be judged. If the patient can only see the large characters in the distance, but cannot see the small characters in the near, it may indicate that the patient has myopia.
However, the specific value of myopia degree cannot be determined by vision measurement alone, and further examination is needed.
2. Measure the length of eyeball
The ophthalmologist will measure the length of the patient's eyeball when judging the degree of myopia. For people with long eyes, the distance from the retina to the back wall of the eye will also become longer, leading to myopia. The commonly used measurement method is A-ultrasound, which measures the length of the eyeball through ultrasound. This process is painless for patients, and can accurately obtain the value of eye length.
By measuring the length of the eyeball, ophthalmologists can preliminarily determine the approximate range of myopia of patients.
3. Refractive state inspection
Ophthalmologists also need to check the patient's refractive status. By measuring the patient's diopter with a refractometer or an automatic refractometer, we can understand the refractive state of the patient's eyes. The focal length of normal eyes can be adjusted freely, but the ability to adjust the focal length of myopia patients is poor, and the length of eye axis is longer. The refractive status examination can help doctors to judge the degree of myopia more accurately.
In addition, ophthalmologists will also observe the patient's pupil reflex, corneal curvature and other indicators to further judge the degree of myopia.
4. Further inspection
If the above examination cannot determine the specific value of myopia degree, the ophthalmologist can also conduct further examination. Common methods include corneal topography, wavefront examination, corneal staining, etc. These examinations can provide more detailed and accurate data to help doctors develop more appropriate treatment plans.
In a word, ophthalmologists need to combine multiple factors such as vision measurement, eye length, refractive status, etc. when judging the degree of myopia, and obtain more accurate data through further inspection. Only through comprehensive examination can doctors accurately assess the degree of myopia of patients and provide more effective treatment and suggestions for patients.
Summary
The process for ophthalmologists to judge the degree of myopia is relatively complex, and it needs to comprehensively evaluate the patient's eye condition through various examinations. Every step plays an important role from measuring vision, measuring eyeball length, refractive state inspection to further inspection. Through comprehensive judgment, doctors can provide patients with more accurate assessment of myopia and develop personalized treatment plans. Therefore, when seeking the help of an ophthalmologist, the patient should cooperate with the doctor's inspection requirements and treat according to the doctor's recommendations.
