Retention of iodinated contrast material within renal cysts in a patient with autosomal dominant polycystic kidney disease

Hyperdense renal cysts, a common condition in autosomal dominant polycystic kidney disease, may be induced by haemorrhage into the cysts. However, hyperdense renal cysts resulting from retention of contrast material after intravenous injection is extremely uncommon because the intravenous administration of contrast material does not induce an increase in the attenuation of renal cysts. We report a case of retention of iodinated contrast material within renal cysts in a patient with autosomal dominant polycystic kidney disease.