What means megalocornea?
Megalocornea (MGC1) is a rare developmental defect characterized by nonprogressive, usually symmetric, bilateral enlargement of the diameter of the cornea (≥13 mm). The cornea is clear and of normal or slightly below normal thickness. Keratometry reveals normal to above normal steepness.
Is Buphthalmos reversible?
Buphthalmos (usually occurring in children presenting before 3 years of age due to stretching of the elastic sclera from raised intraocular pressure [IOP]) Haab striae (breaks in the Descemet’s membrane) Corneal oedema. Optic disc cupping (can be reversible with treatment)
Is Buphthalmos genetic?
Buphthalmia is inherited as an autosomal recessive trait (bu/bu). It has been suggested that this mutation and resulting loss of appropriate gene function perturbs differentiation of the trabecular meshwork, resulting in the buphthalmic phenotype (Knepper et al., 1997).
What is a Microcornea?
Definition. A congenital abnormality of the cornea in which the cornea and the anterior segment of the eye are smaller than normal. The horizontal diameter of the cornea does not reach 10 mm even in adulthood. [ from HPO]
What are the differential diagnoses for buphthalmos and megalocornea?
Congenital glaucoma is usually the primary differential diagnosis given the concern for buphthalmos. Patients with megalocornea will not exhibit ocular hypertension, Haabs striae, optic disc changes seen in congenital glaucoma.
Is megalocornea always bilateral?
It is usually bilateral, and in most cases is X-linked, so the majority of the patients are male. Although a similar picture may be seen in severe congenital glaucoma with buphthalmus, in megalocornea the IOP is normal, there is no corneal edema or opacification, nor is there Haab striae.
What causes large corneas in buphthalmos?
A large cornea can also been seen in buphthalmos as in congenital glaucoma (diffuse enlargement of the eye) but is considered a separate disease and should not be confused with megalocornea. The definitive cause of megalocornea is currently unknown.
What are the signs and symptoms of megalocornea?
In some cases, however, patients can manifest premature cataract formation, retinal detachment, glaucoma, lens subluxation, and primary congenital glaucoma. Diagnosis of megalocornea is generally made in young patients and requires thorough examination of the eye, often under general anesthesia.