A cataract that occurs congenitally as the result of a developmental defect, in contrast to the majority of cataracts that occur in adulthood as the result of degenerative changes of the lens.

Megalocornea is an inherited eye disorder in which the corneal diameter is bilaterally enlarged (greater than 13 mm) without an increase in intraocular pressure. It may also be referred to as 'anterior megalophthalmos,' since the entire anterior segment is larger than normal. Features of megalocornea in addition to a deep anterior chamber include astigmatic refractive errors, atrophy of the iris stroma, miosis secondary to decreased function of the dilator muscle, iridodonesis, and tremulousness, subluxation, or dislocation of the lens. Whereas most affected individuals exhibit normal ocular function, complications include cataract development and glaucoma following lenticular dislocation or subluxation. X-linked recessive inheritance is the most common pattern, accounting for the male preponderance of the disorder (summary by Skuta et al., 1983). Megalocornea sometimes occurs as part of the Marfan syndrome (154700). Genetic Heterogeneity of Megalocornea Autosomal recessive megalocornea has been reported (249300).

The presence of remnants of a fetal membrane that persist as strands of tissue crossing the pupil.