megalocornea


megalocornea

 [meg″ah-lo-kor´ne-ah] a developmental anomaly of the cornea, which is of abnormal size at birth and continues to grow, sometimes reaching a diameter of 14 or 15 mm in the adult.

ker·a·to·glo·bus

(ker'ă-tō-glō'bŭs), Congenital anomaly consisting of an enlarged anterior segment of the eye. Synonym(s): anterior megalophthalmos, megalocornea [kerato- + L. globus, ball]

megalocornea

An X-linked recessive, nonprogressive enlargement of the cornea to 13 mm or greater, which is present at birth; 90% of cases occur in males. The cornea and the limbus are enlarged but histologically normal. Associated findings include anterior megalophthalmos, enlarged ciliary ring with zonular stretching (leading to phacodonesis), ectopia lentis, iridodonesis, iris stromal hypoplasia, posterior embryotoxon, transillumination defects, Krukenberg spindles, trabecular meshwork pigmentation, posterior embryotoxon, Rieger anomaly, goniodysgenesis and cataracts. It is usually isolated, but may be associated with other ocular and systemic findings.

megalocornea

A non-progressive enlargement of the cornea (more than 13 mm in diameter) without significant change in corneal thickness and normal clarity and function. Intraocular pressure is normal and high myopia and astigmatism often occur. It is usually transmitted as an X-linked recessive trait. Some systemic associations include Marfan's syndrome, Apert's syndrome, Down's syndrome, Weil-Marchesani syndrome and osteogenesis imperfecta. See cornea plana; keratoglobus; microcornea.