Kayser-Fleischer Ring

A golden-brown or greenish-brown corneal ring at the level of Descemet’s membrane, caused by copper deposition in the cornea. It is a cardinal sign of Wilson’s disease (hepatolenticular degeneration)

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History

1902 — Bernhard Kayser (1869-1954) first reported a “greenish discoloration of the cornea” in a 23-year-old man with multiple sclerosis, calling it an angeborene grünliche Verfärbung der Kornea (“congenital greenish pigmentation”).

«Die Hornhaut erscheint hier undurchsichtig und von dunkelgrünbrauner Farbe… eine Anhäufung feiner gelber Flecken ganz nahe an der Hinterwand.»
“The cornea appears opaque and of a dark greenish-brown colour… an accumulation of fine yellow spots close to the posterior surface.”

Kayser, 1902

1903 — Bruno Fleischer (1874-1965), in his paper “Zwei weitere Fälle von grünlicher Verfärbung der Kornea”, described two additional cases. He confirmed the ring’s location in the deep peripheral corneal layers (Descemet’s membrane) and noted it appeared in patients with pseudosclerosis (now Wilson disease). He cautiously questioned Kayser’s idea of a congenital cause and excluded silver ingestion (“Argentum nitricum innerlich wurde nicht gebraucht”).

«Bei beiden Kranken fand sich ein schmaler, grünlich-brauner, ringförmiger Streifen am Hornhautrand, im Bereiche der Descemetschen Membran…»
“In both patients there was a narrow greenish-brown ring at the margin of the cornea, in the region of Descemet’s membrane”

Fleischer, 1903

1934 — Werner Gerlach and Wilhelm Rohrschneider published the pivotal study disproving silver as the pigment’s basis. Using spectrographic analysis, they found the corneal ring to be “silberfrei… dagegen findet sich eine Spur Kupfer” (“free of silver, but containing a trace of copper”). This was the first definitive identification of copper as the deposited element, cementing the modern understanding of Wilson’s disease as a disorder of copper metabolism.

This pivotal observation disproved the earlier “silver” theory of Kayser and Fleischer, confirming that copper accumulation from impaired biliary excretion in Wilson’s disease caused the pathognomonic ring.

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Associated Persons

• Bernard Kayser (1869-1954)
• Bruno Fleischer (1874-1965)
• Kinnier Wilson (1878-1937)

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Controversies

Kayser-Fleischer Ring – not to be confused with Fleischer Ring (associated with keratoconus and described in 1906)

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References

• Kayser B. Ueber einen Fall von angeborener grünlicher Verfärbung der Cornea. Klinische Monatsblatter für Augenheilkunde. 1902;40(2):22-25 [Kayser-Fleischer Ring]
• Fleischer B. Zwei weiterer Falle von grunlicher Verfarbung der Kornea. Klinische Monatsblätter für Augenheilkunde 1903; 41: 489-91 [Kayser-Fleischer Ring]
• Wilson SAK. Progressive lenticular degeneration: a familial nervous disease associated with cirrhosis of the liver. Brain 1912; 34(4): 295-507. [Wilson disease]
• Gerlach W, Rohrschneider W. Besteht das Pigment des Kayser-Fleischerschen Hornhautringes aus Silber? Klinische Wochenschrift. 1934;13(2):48-49