To diagnose color blindness, your doctor will perform one of the following quantitative and qualitative tests.
1. Qualitative color blindness test
Use the Ishihara method. The test is very simple, the patient just needs to look at the table and say the number he sees. Based on the results, the doctor will conclude what the disease is. In children who cannot read numbers or letters, there will be some special tables used to diagnose color blindness.
Some notes for the Ishihara method: the patient's visual acuity must be above 6/60 (1/10). Good lighting. Examine each eye. The table is held 75cm away from the patient and must be perpendicular to the visual axis. Looking time is 3-5 seconds.
Based on Ishihara, the Enchroma method helps determine the degree and type of color blindness a person has. At the same time, the test also has a classification section for adults and children from 5 years old.
2. Quantitative color blindness test
To analyze in detail and the patient's ability to accurately recognize colors, the doctor uses the Farnsworth-Munsell 100 method. The test includes 4 trays, which will contain many small discs with different colors. The patient needs to arrange the colored discs in ascending order of color. To get accurate results, the test must be done in a place with lighting closest to natural light.
With this technique, each color disc will be numbered at the bottom to easily check the results. If the patient's color arrangement is as similar as possible to the sample, the diagnosis will be accurate. The Farnsworth-Munsell 100 technique helps detect color blindness and its severity.
In addition to the above two ways, you can test for color blindness online through famous smart devices such as color blind test, giving quite accurate overall results.
However, checking online can lead to errors. Therefore, it is necessary to see an eye specialist for early examination, consultation and treatment, and early detection of eye diseases.
