Functional MR Imaging In Diagnosing Bone Tumors And Tumor-like Lesions

Objective: To assess the diagnostic potential of MR-PWI, MR-DWI and MRS in differentiating benign from malignant bone tumors and tumor-like lesions.Materials and Methods: MR-PWI and MR-DWI were performed on 39 patients, and 18 patients underwent MRS using a GE signa 1.5T MR/I with a body/surface coil. The methods were as followed:1. MR-PWI: A bolus of gadopentetate dimeglumine (0.2 ml/kg body weight) was rapidly administered by means of a power injector with an injection rate of 2.5 ml/s through intravenous catheter in right or left antecubital vein. The perfusion imaging was started with GRE-EPI sequence as soon as the injection of the contrast medium commenced. Signal intensities were measured on delineated ROI and TIC was gotten using the functool 2 software system. Type of TIC, signal decreasing in first-pass period, maximum slope of TIC and signal difference between two standard states were compared between benign and malignant bone lesions. BV, MTT and BF were also compared.2. MR-DWI: With b value of 165 s/mm2,300 s/mm2,600 s/mm2,1000 s/mm2, imaging were performed with SE-EPI fast scan sequence with diffusion in three directions. ADC values were obtained and compared on delineated ROI using the functool 2 software system.3. MRS: Surface coil was selected and spectra for each volume of interest were acquired by using point-resolved surface coil spectroscopy sequence. Select ROI on metabolism-anatomy chart and obtain the MR spectroscopic data with Functool 2 software, including value of Cho, Cr, Lip and Ch/Cr ratio.