Presentation
Numbness and urinary symptoms.
Patient Data
There is an 8 x 12 x 14 mm well-defined high signal (on T1/2) intradural intramedullary mass lesion involving the conus medullas that loses signal in STIR images consisting of fat component.
After contrast injection, the conus medullaris fat equivalent signal mass shows internal septal enhancement.
Case Discussion
The appearances are in keeping with a conus medullaris lipoma. There are few fat-containing intradural lesions including lipoma and dermoid cyst. The presence of a solid enhancing component makes the diagnosis dermoid almost certainly and excludes a simple lipoma.