Table 2.

The features of the imaging examination of AAM.

Imaging examination
Ultrasonography	Majority: cystic hypoechoic or isoechoic Minority: uneven medium and low mixed echoes
	With probe pressure: flow sensation
	CDFI: blood flow signals can be detected around the tumor
CT	Low-density soft tissue shadow After contrast administration: slightly irregular and enhanced
MRI	T1WI: hypointensity, lower than or equal to the muscle tissue T2WI: hyperintense, hypointensity bands arranged in layers and vortices, forming “laminated” or ‘swirled” appearance
	After contrast administration: gradual progressive enhancement

CT, computed tomography; MRI, magnetic resonance imaging.