Coloboma simply means a defect, but its use is usually restricted to congenital defects of the eye. These may involve the lens, the iris, the retina or the eyelid.
n. a defect in the development of the eye causing abnormalities ranging in severity from a notch in the lower part of the iris, making the pupil pear-shaped, to defects in the retina, choroid, and optic nerve *fundus. A coloboma of the eyelid is a congenital notch in the lid margin.
(Bourneville’s disease, epiloia) a hereditary disorder in which the brain, skin, and other organs are studded with small plaques or tumours; eye involvement includes retinal tumours (astrocytic *hamartomas), *coloboma, *papilloedema, optic nerve gliomas, and eyelid neuromas. Symptoms include epilepsy, learning difficulties, and behavioural disorders.... tuberous sclerosis
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