caliceal diverticulum

calyceal diverticulum an epithelium-lined cavity adjacent to a renal calyx, often inflamed and filled with cloudy fluid or pus that in time may calcify into a calculus. Two types are distinguished: type I is more common, a bulbous diverticulum connected by a long thin neck to one pole of a calyx; type II is a rare type, a round diverticulum connected by a short neck to the central part of a calyx. Called also pyelocalyceal d.