Retinitis pigmentosa
Retinitis pigmentosa refers to a group of hereditary eye diseases that result in degeneration of the retina. It is one of the most frequent causes of vision loss during middle age. Some three million people worldwide are affected by one of the various types of retinitis pigmentosa.
The disease takes a gradual course lasting decades. Night blindness is an early symptom in many cases. The patient’s visual field gradually narrows and contrast and colour vision loss occurs. Later, visual acuity increasingly deteriorates, in many cases resulting in blindness.
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