The Ishihara test is a test performed to check the eye's ability to see and distinguish colors. This test is most often used to detect color blindness, whether it is total or partial color blindness.
Color blindness does not always cause the sufferer to see all colors as gray. Color blindness like that is actually rare. People who are color blind generally cannot distinguish between certain colors, for example, to distinguish between red and green, or blue and yellow.
The Ishihara test can be used to find out if a person is color blind. This color blindness test can be done in a hospital by an ophthalmologist or done yourself at home.
Although it can be done independently, if the results of a home examination indicate a color blind condition, it is advisable to immediately consult a doctor to confirm the diagnosis.
Ishihara Test Indications
The Ishihara test can be performed on everyone. However, doctors usually recommend the Ishihara test in people with the following conditions:
- Have a family member who suffers from color blindness
- Having difficulty distinguishing colors, for example unable to distinguish green from red
- Having difficulty seeing whether a color is bright or not, for example not being able to distinguish bright yellow from light yellow
- Having difficulty distinguishing shades of color, for example unable to distinguish red from purple
Ishihara Test Warning
As previously explained, the Ishihara test can be performed on anyone. However, in some cases, this test may need to be preceded by other eye examinations, such as in people with vision problems that are severe enough to not see clearly.
Therefore, inform your doctor in advance if you have vision problems, both to see color and to see as a whole. Also tell your doctor about any other complaints you have, a family history of eye health, and any medications or supplements you are currently taking.
Before the Ishihara Test
The Ishihara test does not require any special preparation. If the patient uses glasses to see, it is recommended to wear glasses when performing this test.
Ishihara Test Procedure
The Ishihara test was conducted in a room with sufficient lighting. The ophthalmologist will perform tests on both eyes of the patient one at a time. In the process, the patient will be asked to close one eye and look at the image on the test paper.
The complete Ishihara test generally consists of 38 picture cards. If it is only for screening purposes (initial tests), fewer cards can be used.
On each card there is an image of a circle formed from dots with different colors, brightness levels, and sizes. The dots can form a pattern of numbers, letters, symbols, or grooves. During the test, the patient must read the letters or numbers in the picture with one eye closed.
After finishing with one eye, the doctor will ask the patient to close the other eye and perform the same test as before. In addition to finding the letters or numbers in the image, the doctor may also ask the patient to describe the brightness of the colors seen.
After the Ishihara Test
Ishihara test results can generally be known immediately after the test is completed. The test results can help doctors detect some conditions of color blindness, such as:
- Protanopia, which is difficulty distinguishing green from blue or red
- Deuteranopia, which is difficulty distinguishing purple from red or green
- Achromatopsia, which is total color blindness, where the sufferer can only see gray
If color blindness is found, the doctor may order additional tests to confirm the diagnosis. Doctors can also perform further tests to determine whether color blindness is caused by a disease, such as diabetes or glaucoma.
Ishihara Test Risk
The ishihara test does not cause any side effects or complications. This test is safe to be carried out by anyone and is effective for detecting eye problems in seeing color.
