COLOUR TEST
ISHIHARA TEST
The Ishihara Colour Test is one of the most commonly used tests to diagnose and classify colour vision disorders (dyschromatopsia). Moreover, it is extremely useful to discover other pathologies related to the optic nerve condition like optic neuritis, nervous compression and even pathologies that affect the orbit such as thyroid ophthalmopathy. This test allows us to distinguish perception disorders of two great colour spectrums: the red and green axis. Protanopia (Dalton) in which the red spectrum is very reduced due to patients’ lack of cons for red colour whereas the blue-green spectrum is seen greyish. Deuteranopia (Nagel) is the one in which green is seen like grey colour because of the absence of cons that differentiate green colour. This test doesn’t allow us to discriminate blue-yellow axis defects. If you see 17 or more correct figures, this is a normal exploration. If they are less than 13, this is a pathologic one. Please follow the order of the images shown below and jot down on a piece of paper the number you are able to see in each image. After making a note of all figures, check your results with those you will find at the end of this page. If your results aren’t regular, we advise you to to be seen by an ophtalmologist in order to check your ocular condition.
TEST RESULTS:
- Pepole with NORMAL colour vision will see, in this order: 12, 8, 6, 29, 57, 45, 5, 3, 15, 74, 2, 6, 97, 5, 7, 16, 73, 26, 42, 35, 96.
- Patients with a red-green axis deficincy usually see, in this order: 12, 3, 5, 70, 35, 2, 5, 17, 21, X, X, X, X, X, X, X, X.
- In the last four images:
- A protanope (Dalton) will see: 6, 2, 5, 6.
- A deuteranope (Nagel) will see: 2, 4, 3, 9.