Figure 12a. Localized cystic disease of the kidney in a 43-year-old man being evaluated for abdominal trauma. The localized cystic disease was an incidental finding. Axial contrast-enhanced CT scans show a cluster of cysts separated by normal enhancing renal parenchyma in the upper pole of the right kidney. There is no pseudocapsule surrounding the cysts. Note that the small cyst at the 6-o’clock position (arrow in a) is clearly separate from the aggregate of cysts.