Asteroid hyalosis is a condition in which white, refractile, round bodies develop in the vitreous. The condition is associated with aging, is more often unilateral, occurs more often in men, and has a controversial association with diabetes mellitus. The bodies are complexes of calcium and lipids similar to hydroxyapatite. Asterodi hyalosis rarely causes decrease in vision, but it can make the view difficult for a doctor examining the eye. When this occurs, a vitrectomy can clear the asteroid bodies to allow proper examination as in cases of diabetic retinopathy or follow-up of fundus lesions.