Macular corneal dystrophy, also known as Fehr corneal dystrophy named for German

ophthalmologist Ophthalmology ( ) is a surgery, surgical subspecialty within medicine that deals with the diagnosis and treatment of eye disorders. An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Followin ...

Oskar Fehr (1871-1959), is a rare pathological condition affecting the

stroma of cornea The stroma of the cornea (or substantia propria) is a fibrous, tough, unyielding, perfectly transparent and the thickest layer of the cornea of the eye. It is between Bowman's membrane anteriorly, and Descemet's membrane posteriorly. At its centr ...

. The first signs are usually noticed in the first decade of life, and progress afterwards, with opacities developing in the cornea and attacks of pain. The condition was first described by

Arthur Groenouw Arthur Groenouw (27 March 1862 – 1945) was a German ophthalmologist born in Bosatz, a village near Racibórz, Ratibor. He studied medicine in University of Breslau, Breslau, and was an assistant to physiologist Rudolf Heidenhain (1834–189 ...

in 1890.Groenouw A. Knötchenförmige Hornhauttrübungen (noduli corneae). Arch Augenheilkunde. 1890;21:281–289.

Signs and symptoms

Onset occurs in the first decade, usually between ages 5 and 9. The disorder is progressive, vision changes with ageing from 2nd decade to 3rd visual impairment may seen in 4th and 5th decade severe visual impairment can be seen Minute, gray, punctate opacities develop. Corneal sensitivity is usually reduced. Painful attacks with photophobia, foreign body sensations, and recurrent erosions occur in most patients. Macular corneal dystrophy is very common in Iceland and accounts for almost one-third of all corneal grafts performed there.

Genetics

Macular corneal dystrophy is inherited in autosomal recessive fashion and is thought to be caused by the lack or abnormal configuration of

keratan sulfate Keratan sulfate (KS), also called keratosulfate, is any of several sulfated glycosaminoglycans (structural carbohydrates) that have been found especially in the cornea, cartilage, and bone. It is also synthesized in the central nervous system w ...

. Most cases of MCD are caused by mutations in CHST6 gene. The gene CHST6 is a carbohydrate sulfotransferase encoding an enzyme designated corneal N-acetylglucosamine-6-sulfotransferase. In MCD type I, various mutations lead to inactivation of the enzyme, in MCD type II, inactivation is caused by large deletions and/or replacements in the gene.

Diagnosis

Treatment

Corneal transplantation Corneal transplantation, also known as corneal grafting, is a surgical procedure where a damaged or diseased cornea is replaced by donated corneal tissue (the graft). When the entire cornea is replaced it is known as penetrating keratoplasty a ...

is often required.

References

External links