Lipid deposition at the limbus.

Lipid deposition at the limbus is a feature of familial and non-familial dyslipoproteinemias and can also occur without apparent accompanying systemic abnormality. Hyperlipoproteinemia, most notably type II hyperlipoproteinemia, is frequently associated with bilateral corneal arcus, with less common association in types III, IV and V. Diffuse bilateral opacification of the cornea with accentuation towards the limbus is a feature of HDL deficiency syndromes and LCAT deficiency. Whereas the lipid accumulation of hyperlipoproteinemia may be representative of excessive insudation of lipoprotein from plasma into the cornea that of hypolipoproteinemia is more likely to be a consequence of defective lipid clearance. The situation is yet further complicated by the modifying influences of secondary factors, both local and systemic.