intraosseous epidermoid cyst

Intraosseous

epidermal cysts. AP X ray. Eccentric lytic lesion with sclerotic borders and cortical defect with adjacent soft tissue swilling

Intraosseous

epidermal cysts. Intermediate SI on axial T1WI is probably due to the cholesterol component of the lesion (long arrow). Low Signal intensity is due to calcium from cortical destruction (short arrow).

Intraosseous

epidermal cysts. The axial diffusion weighted image shows mixed signal intensity mass

Masses of

developmental and genetic origin affecting the paediatric craniofacial skeleton. Intraosseous dermoid cyst (DC) in a 17-year-old male presenting as a gradually enlarging right supraorbital swelling since three years. a Cystic lesion in the right frontal bone (arrow) with non-lipomatous contents on axial T2. On T1 (b) and fat-saturated contrast-enhanced T1 (c), the lesion appears hypointense and displays intracystic serpiginous hyperintense areas which correspond to haemorrhage, high protein content or saponification (arrows). d DWI reveals high signal on the b = 1000 image (asterisk, upper image part) and low signal on the ADC map (asterisk, lower image part, ADC = 0.6 × 10−3 mm2/s), compatible with restricted diffusion and characteristic of an epidermoid cyst

Masses of

developmental and genetic origin affecting the paediatric craniofacial skeleton. DC with bone remodelling in a 14-year-old male with lateral supraorbital soft tissue swelling and induration. a Axial CT (bone window) shows well-demarcated cystic subcutaneous lesion (arrowhead) with frontal bone scalloping and no cortical erosion (arrow). b Three-dimensional CT VR reconstruction shows bone remodelling in the supraorbital left area (arrow). c DWI reveals high signal on the b = 1000 image (arrowhead, upper image part) and high signal on the ADC map (arrowhead, lower image part, ADC = 2.5 × 10−3 mm2/s), compatible with no restricted diffusion and characteristic of a DC. d Peripheral lipid density on T2 (arrow, upper image part) and T1 with low signal (arrow in e) in gadolinium-enhanced coronal fat-saturated T1. Central soft tissue density on T1 (arrowhead in lower image part) with no contrast enhancement (arrowhead in e), corresponding to squamous debris