Table 2.

Comparative features of congenital overgrowth syndromes causing hemifacial hypertrophy and congenital infiltrating lipomatosis of the face (CIL-F)

Condition	Neurofibromatosis26,27	Klippel–Trenaunay–Weber syndrome28	Proteus syndrome29,30	Fibrous dysplasia (McCune–Albright syndrome)31,32	CIL-F1,3,4,17,21
Origin	Neural	Vascular	Mixed	Osseous	Fat
Clinical features	Smooth café-au-lait spots	Soft tissue hypertrophy of extremity	Epidermal nevi	Irregular café-au-lait spots	Increased density of facial hair on affected side
			Macrodactyly		Hemimacroglossia
	Neurofibromas	Venous malformations	Scoliosis	Precocious puberty	Ptosis of upper lip, enlarged lower lip
	Lisch nodules	Capillary haemangiomas	Soft tissue/bony overgrowth.	Pitiutary adenoma	Early eruption of deciduous permanent teeth
	Gracile bones/ribs	Limb overgrowth	Unilateral precocious dental development	Hyperthyroidism	Regional macrodontia
CT features	Hypodense soft tissue with homogeneous enhancement	Hypodense/mildly hyperdense soft tissue	Distortion of skeletal features with rapid progression	Osseous expansion	Fatty infiltration Poorly defined margins
				Cystic: fluid-like density
		Calcified phleboliths	Fatty infiltraton of muscles	Mature: ground-glass density	Hypertrophy of underlying facial skeleton
		Nodular enhancement	Vascular malformations	Poorly defined peripheral sclerosis
MRI features	Low signal intensity on T1WI	Marked T2 hyperintensity	Calvarial thickening	Intermediate to low signal on T1WI	Diffuse fatty infiltration with T1, T2 hyperintensity
			outer table defects
	T2 hyperintensity with central hypointensity (target sign)	Phleboliths	Focal fatty infiltration	Intermediate to high signal on T2WI	Hypointensity on fat-suppressed images
	Homogeneous enhancement	Peripheral nodular enhancement	Asymmetric fatty masses in suprahyoid neck	Heterogeneous contrast enhancement

T₁WI, T₁ weighted images; T₂WI, T₂ weighted images.