The limbus sign is a ring of
dystrophic calcification evident as a "milky
precipitate" (i.e. abnormal white color) at the
corneal limbus. The corneal limbus is the part of the eye where the
cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical ...
(front/center) meets the
sclera (white part of the eye). Thought to be caused by increased calcium concentration in the blood, this sign however persists after
calcium phosphate
The term calcium phosphate refers to a family of materials and minerals containing calcium ions (Ca2+) together with inorganic phosphate anions. Some so-called calcium phosphates contain oxide and hydroxide as well. Calcium phosphates are wh ...
concentration returns to normal. Compare the limbus sign (calcification) with
arcus senilis (lipid).
[Edwards, Mark E. (2008)]
Geriatric physical diagnosis: a guide to observation and assessment.
McFarland & Company. p. 96. Retrieved January 7, 2012.
References
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Eye
Medical signs