Colour Blindness

Colour blindness occurs occurs in 4% of males in any race. It is extremely rare in females and is genetically inherited. It is recessive in females which means that they can pass it on to their sons but they rarely display the problem themselves.

The vast majority of people with colour deficiency have this from birth and are colour deficient in the red/green area. These individuals are called protanopes. The condition is not progressive and is never acquired. People who have an acquired colour vision defect will have some ocular pathology and will require further investigation. An example of this is optic neuritis which can be the presenting symptom of neurological conditions such as multiple sclerosis.

The standard test for detecting red/green colour defects is the Ishihara test (click for chart).

Colour Spectrum

More involved test are available at centres for patients with colour defects. There is no cure for patients with colour deficiency. Recently there has been some publicity about corrective lenses for colour deficiency. These are called Chromogen lenses which are available in both spectacle and contact lens form. Initially people felt that this did correct the problem as patients passed the Ishihara test when wearing these lenses however further investigation concluded that the area of colour deficiency was just shifted along the spectral band.

All information is for reference purposes only; if you have any concerns we recommend that you visit a qualified optician.

Blepharitis;
Cataracts;
Conjunctivitis;
Corneal Abrasion;
Dry Eyes;
Ectropion;
Entropion;
Glaucoma;
Iritis / Uveitus;
Keratoconus;
Laser Treatment;
Macula Degeneration;
Meibomian Cyst;
PVD;
Short Sightedness.

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