Fig. 2

Computed tomography changed over time. Non-enhanced CT performed 3 years previously showed a 5-cm cystic mass with a uniform high density (arrow) (a), while non-enhanced CT performed 6 months previously showed a cystic mass had grown to 8 cm with a uniform low density (b). On the most recent CT scans, the concentration in the cyst was slightly reduced in comparison to these images (CT value: 20.3HU), and the diameter of the cyst had grown to 10 cm (c)