CONGENITAL LENS COLOBOMA AND ASSOCIATED PATHOLOGIES

Coloboma of the lens is characterized by notching of the equator of th e lens. The cause of the condition is faulty development of the zonule . The lens deprived of its normal pull in the defective region is thic ker and more spherical as if there were no loss of its substance. We r eport five cases of lens coloboma and localized zonular defect without any associated systemic anomalies. One case included retinal detachme nt; another included an iris coloboma; and a third included iris, chor oid and optic disk colobomas and retinal detachment with lens coloboma . The remaining two cases were without associated ocular anomalies. Th e pathogenic mechanisms and relationship of this defect with the diffe rentiation of the tertiary vitreous and development of the zonule is d iscussed. The defect most likely occurs in the third to fourth months of gestation during differentiation of the tertiary vitreous in respon se to toxic, inflammatory or genetic factors.