Table 3 Salient features of malignant skull lesions on CT and MRI
Skull Lesion | CT | MRI |
|---|---|---|
Multiple myeloma (multiple) | Osteolytic lesions without sclerotic rim, “punched-out lesions”. | Hypointense T1, hyperintense T2. “Salt and pepper marrow infiltration” is the most common pattern. Typically enhance. |
Osteosarcoma | Lytic lesion, ill defined borders. Aggressive periosteal reaction. Variable amount of osteold matrix. | Variable appearance. |
Metastases (may be solitary or multiple) | Lytic, sclerotic or mixed depending on the primary tumour. | Hypo/isointense T1, hyperintense T2. Typically enhance (unless sclerotic). |
Chordoma (skull base, midline) | Lytic destructive expansile lesion of the clivus. | Hypointense T1, lobules of high signal on T2. Heterogeneous enhancement. |
Chondrosarcoma (skull base, paramidline) | Osteolvtic lesion. Chondroid matrix with “rings and arcs”. | Hypo/isointense T1, hyperintense T2. “Whorls of enhancement”. |