Glaucoma refers loss of retinal ganglion cells in a characteristic pattern of optic neuropathy usually associated with increased intraocular pressure.

Intraocular pressure that is 2 standard deviations above the population mean.

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).

Abnormal accumulation of fluid and swelling of the stroma of cornea.

An elevation in the ratio of the diameter of the cup of the optic disc to the total diameter of the disk. The optic disc has an orange-pink rim with a pale center (the cup) that does not contain neuroretinal tissue. An increase in this ratio therefore may indicate a decrease in the quantity of healthy neuroretinal cells.