Colour blindness: Treatment, symptoms, advice and help
About colour blindness
Colour blindness is a mild disability wherein the affected individual is unable to perceive the difference between colours. The organ of vision is the eye which constitutes certain cells like ‘rods’ and ‘cones’ placed on the retina and responsible for night vision and colour vision respectively. Any defect in ‘the cones’ would result in impairment of colour vision.
The grade of colour blindness may vary from mild to severe, although it is extremely rare to encounter the severe grade of colour blindness. It is mostly a genetic disorder but other factors may also play a role in its causation.
Colour blindness: Incidence, age and sex
Colour blindness is a fairly common occurrence in general population, though it may remain unnoticed in many individuals. It is more frequent in men and very rarely seen in women.
Signs and symptoms of colour blindness: Diagnosis
Colour blindness is of different types like red-green, blue-yellow and total, of which red-green colour blindness is the commonest. The affected individual is unable to distinguish between different colours. For example, individuals with red-green colour blindness can see both the colours but fail to discriminate between them. Total colour blindness also called ‘achromatopsia’ is the most severe but rare form of colour blindness characterised by inability to distinguish between any colour and associated with vision impairment and nystagmus (rapid, to and fro movement of eye). Mild cases of colour blindness are usually asymptomatic and may be first diagnosed during routine eye examination. The eye specialist uses special chart called Ishihara chart for detection of colour blindness.
Causes and prevention of colour blindness
Colour blindness is a genetic X linked recessive disorder and inherited from one of the parents. It is very rare in women since two defective X chromosomes would be required in a woman for colour blindness to manifest. A woman with only one defective X chromosome is a carrier of colour blindness and will not show any clinical feature. However a carrier woman can pass this defective chromosome to her son who will then manifest the clinical features of colour blindness.
Very rarely, colour blindness may be acquired as a result of drug toxicity (hydroxychloroquine) or injury of brain or eye.
Colour blindness: Complications
There are as such no health complications of colour blindness. However individuals with colour blindness may find difficulty during driving or in certain professions like that of pilot, traffic police and designer.
Colour blindness: Treatment
Colour blindness is a chromosomal, genetic disorder and thus has no treatment. It is a life long condition but colour blind individuals learn to manage their handicap with time and practice.