The Study Of The Value Of MR DWI And Single-voxel ~1H MR Spectroscopy In The Diagnosis Of Breast Diseases

Objective: To evaluate the diagnostic effectiveness of MR diffusion-weighted imaging (DWI),and single-voxel1H MR spectroscopy (MRS) in patients with breast tumor.Methods:60 patients with breast lesions detected by physical examination or mammography underwent MR examination on a 1.5T scanner (GE,Signa INFINITY) pre-operatively. MR examinations included DWI with b value of 100s/mm2,600s/ mm2 and 1000s/mm2 by single-shot EPI sequence,and single-voxel 1H MRS by Spectral Spatial PRESS.The mean apparent diffusion coefficients (ADC) of the lesions were calculatede on DWI with both b value of 100s/mm2,500s/mm2 and 1000s/mm2.Lesions presenting a dectectable Choline single in their spetra at 3.2ppm were diagnsoed as malignant.The sensitivity,specificity,and accuracy of DWI,and single-voxel 1H MRS regarding the diagnosis of breast lesions were determined respectively.Results:Among 60 patients,pathology revealed 30 malignant and 30 benign lesions. We selected the ADCcutoff value of 1.08×10-3mm2/s for b=1000s/mm2 , 1.32×10-3mm2/s for b=600s/mm2 and 1.60×10-3mm2/s for b=600s/mm2 .At the cutoff values ,sensitivity and specificity were 97% and 77% for b=1000 ,80% and 93% for b=600s/mm2,38% and 83% for b=100s/mm2. The difference of the accuracy among the DWI for b=600 s/mm2 and b=1000 s/mm2 showed statistical significance but the differenc of the accuracy among the DWI for b=100 s/mm2showed however no statistical significance . For MRS, the sensitivity and specificity were 53.3% and 93.3%.Conclusion: DWI and MRS can provide the functional and cytologic information of breast tumor.Due to its short scan time and no need of contrast agent ,DWI is an easy and effective method for breast cancer diagnosis compared with MRS.The accuracy of ADC with high b-value (b=1000s/mm2) is promising. MR spectroscopy could complement MR imaging fingdings to improve the specificity, but limited by technics and the pathologic types of tumors.DWI and MRS have effective value in the diagnosis of breast tumor.Combination of DWI and single-voxel 1H MRS could give more information in differentiating breast lesions and reduce the number of unnecessary biopsies.