Matrix stone in ureter and bladder simultaneously.

Matrix stone is a rare form of urinary calculi. We report the imaging findings of urinary matrix stones in a patient with a history of diabetes mellitus. The stones, located in the left ureter and bladder, were characterized as calcified peripheral enclosing a large amount of gas on computed tomography (CT). To our knowledge, this is the first reported case of matrix stones located both in the ureter and bladder simultaneously.