Presentation
Large frontal subgaleal swelling with disfigurement 18 months before.
Patient Data
Midline frontoparietal large subgaleal well defined encapsulated ovoid mass lesion measures 6.5 x 6 x 2.5 cm. The mass elicits homogeneous fat density (about -121 HU). Preserved underlying calvarial bone with no erosive or destructive changes.
The mass elicits homogenous fat signal intensity (high signal in T1 and T2).
Case Discussion
Subgaleal lipomas are benign adipose-containing tumors that occur between the periosteum and the galeal aponeurosis of the scalp. It presents homogeneous fat density in CT with no associated bony erosive changes. It elicits fat signal in MRI. Differential diagnosis: epidermal inclusion cyst and subgaleal hematoma.