Magnetic resonance imaging of lipoma and liposarcoma: potential of short tau inversion recovery as a technique of fat suppression.
The present limited retrospective study was performed to assess MR imaging of lipomatous tumours of the musculoskeletal system and to evaluate the potential of the T2 short tau inversion-recovery (STIR) technique for differentiating lipomas from liposarcomas. Magnetic resonance imaging of 12 patients with lipomatous tumours of the musculoskeletal system (eight benign lipomas, three well-differentiated liposarcomas and one myxoid liposarcoma) were reviewed. Benign lipomas were usually superficial and showed homogeneity on T1- and T2-weighted spin echo sequences. Full suppression at T2 STIR was readily demonstrated. In contrast, the liposarcomas in the present series were all deep-seated. Two well-differentiated liposaromas showed homogeneity at long and short relaxation time (TR) but failed to show complete suppression at T2 STIR. One case of well-differentiated liposarcoma (dedifferentiated liposarcoma) and one of myxoid liposarcoma showed mild and moderate heterogeneity at T1 and T2, respectively, and posed no difficulty in being diagnosed correctly. In conclusion, short and long TR in combination with T2 STIR show promise in differentiating benign from malignant lipomatous tumours of the musculoskeletal system, when taken in combination with the position of the tumour.
Pang
A K
AK
Department of Radiology, Christchurch Public Hospital, New Zealand.
Hughes
T
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008067:Lipoma / Q000473:pathology*; D008080:Liposarcoma / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D019042:Muscle Neoplasms / Q000473:pathology*; D012189:Retrospective Studies