Kayser-Fleischer rings
Kayser-Fleischer rings, sometimes shortened to K-F rings, are caused by copper deposition in the cornea and are a specific, clinical sign of Wilson disease.
Clinical presentation
They are usually brown or dark reddish in color. Early on they may need a slit lamp to be visible before they become visible to the naked eye. The ring can also be incomplete initially. Kayser-Fleischer rings are present in 95% of Wilson disease cases, including in nearly all cases with neurological manifestations . The density of the ring correlates well with the activity of the disease .
The rings are not pathognomonic for Wilson disease.
Pathology
Kayser-Fleischer rings are caused by direct copper deposition in the Descemet membrane of the cornea and are thought to be from epithelial cells absorbing copper from the aqueous humor .
Treatment and prognosis
After commencement of copper chelating agents (e.g. penicillamine), the size of the rings usually diminish and may eventually vanish altogether .
History and etymology
They were initially described by German ophthalmologist Bernhard Kayser (1869-1954) and German physician Bruno Fleischer (1848-1904) in 1902 and 1903 respectively .