Sacral Masses

Case A: A CT scan of the sacrum depicts a large, well-delineated, midline sacral mass extending into the presacral region. Scattered amorphous calcifications are present. A T2-weighted MRI scan shows heterogeneous hyperintensity. T1-weighted precontrast and postcontrast MRI scans illustrate avid peripheral enhancement of the predominantly T1 hypointense mass.

Case B: A CT scan of the sacrum illustrates a large, expansile lytic lesion with a narrow zone of transition extending to the sacroiliac joints bilaterally. No residual bony matrix is present. T2-weighted MRI scan demonstrates corresponding T2 hyperintense soft tissue throughout the visualized sacrum with involvement of the visualized sacral foramina. T1-weighted precontrast and postcontrast images show heterogeneous enhancement of an amorphous T1 hypointense sacral mass with extension into both the presacral and epidural spaces.

Case C: A CT scan of the sacrum reveals an asymmetric, ill-defined, lytic lesion in the left hemisacrum that traverses the left-sided neural foramina and extends to the left sacroiliac joint. No bony matrix is apparent in the involved regions. T2-weighted MRI shows heterogeneous hyperintensity. T1-weighted precontrast and postcontrast MRI disclose heterogeneous enhancement of the T1 hypointense mass, which abuts the cartilaginous disk spaces.