Value of MR T_1/T_2W Perfusion in Differential Diagnosis of Benign and Malignant Musculoskeletal Lesions

Objective Contrast-study the effects of MR T2W and T1W perfusion in differential diagnosis and of benign from malignant musculoskeletal lesions and to evaluate the clinical significance of T2W perfusion.Methods94 patients with musculoskeletal lesions were performed MR T2W perfusion after T1W perfusion,shapes of time versus signal intensity(SI-T) curves,maximum variance as well as maximum slope of the curves and first pass(FP) time were recorded.SI-T curves were divided into four types both in T1 and T2W perfusion.Receive operrating characteristic curse(ROC) was used to determine the threshold of malignant,its sensitivity,specificity as well as accuracy were calculated respectively.The consistency of maximum perfusion areas of two methods was observed.ResultsType Ⅰ and type Ⅳ curves of T2W perfusion can differentiate benign and malignant lesions on some extent.Maximum signal decrease,maximum slop of SI-T curves and FP time in T2W perfusion had no significant differences between benign and malignant lesions(P0.05).For T1W perfusion,on the other hand,most lesions with type Ⅰ SI-T curves were malignant,and most lesions of type Ⅲ or Ⅳ curves were benign.The average value of signal increase of benign lesions in FP period of T1W perfusion was 29.20%,malignant lesions 73.92%(P0.001).The average value of maximum slope of SI-T curves of benign lesions was 3.49,malignant 9.57(P0.001).ROC analysis indicated that if signal increasing 44.50% as the threshold of malignant,diagnostic sensitivity,specificity and accuracy was 98.50%,86.70%,and 88.30%.With maximum slope of SI-T curve 5.09 as threshold of malignant,its sensitivity,specificity and accuracy was 96.20%,85.60% and 86.17%.14(14.90%) cases maximum perfusion areas observed with the two perfusion methods were identical,and 80(85.10%) were separated.ConclusionMR T2W perfusion was not so valuable as T1W perfusion in differential diagnosis of benign or malignant musculoskeletal lesions.The variance of signal in FP period of T1W and T2W perfusion may be more depend on both intravascular and extravascular Gd-DTPA other than Gd-DTPA of intravascular alone.