Presentation
Incidental finding.
Patient Data
Note: This case has been tagged as "legacy" as it no longer meets image preparation and/or other case publication guidelines.
Unenhanced and portal venous phase imaging was done.
A 12 mm renal cyst with high attenuation of internal contents (80 HU to 100 HU) which does not increase further after contrast administration, compatible with hemorrhagic contents. In the absence of further findings, this can be safely left alone.
Case Discussion
When facing such a lesion, the question which needs to be answered is whether this lesion is surgical or not. A study has suggested that a homogeneous mass measuring 70 HU or greater at unenhanced CT has a greater than 99.9% chance of representing a high-attenuation renal cyst. This is classified as a Bosniak type 2 cyst.