Magnetic resonance imaging of intramuscular haemangiomas with emphasis on contrast enhancement patterns.

Fifteen patients with intramuscular haemangiomas were evaluated with magnetic resonance imaging (MRI). Phleboliths were demonstrated by plain films or CT in six cases, which are characteristic for haemangioma. MRI showed intermediate or slightly high signal intensity on T1-weighted spin-echo images, and overall extremely bright signal on T2-weighted images. Twelve patients had a heterogeneous signal intensity and serpentine pattern on all sequences. A draining vessel was identified in a patient with histologically confirmed diagnosis of arteriovenous type of hemangioma. In three cases with localized small lesions, the MR appearance on T1 and T2-weighted conventional spin-echo sequences was homogenous. Two of the three showed a serpentine pattern on contrast enhanced images. In a patient with a soft tissue mass suspected of representing a haemangioma, MRI may provide more specific information, regarding the characteristics and extent of the lesion than other imaging techniques. In small localized lesions, contrast enhanced MRI may also offer significant advantage, making the identification of serpentine pattern possible which is a characteristic morphological feature of haemangioma.