Primary Study on Diffusion Weighted Imaging with Background Suppression(DWIBS) in Detecting Neoplasm / 实用放射学杂志

ABSTRACT

Objective To study the applied value of diffusion weighted imaging-DWIBS(diffusion weighted imaging with background suppression) in detecting the body tumour.Methods 10 healthy volunteers and 20 patients with histologically proven tumour were examined by diffusion Weighted MR with different techniques of background/fat body signal suppression.STIR-EPI sequence and spin echo-echo planar imaging(SE-EPI) sequence with chemical shift selective(CHESS) pulse were compared in terms of their degree of fat suppression.The diffusion weighted imaging features of control group and patients with tumour were observed and the values of ADC were measured.Results Fat suppression with STIR-EPI sequence in neck,chest,spine and extremity was well and SE-EPI with CHESS pulse in chest,abdomen,pelvic was satisfying.Signal to noise ratio(SNR) wss higher in SE-EPI with CHESS than that in STIR.The glands,spleen,peripheral nerves,lymph nodes and so forth could be showed by DWIBS in control group.85% malignant lesions were well visualized and appeared as high signal intensity and lower signal intensity in similar PET imaging,but the lesions only in 3 patients are not well visualized including pancreas cancer(1 case),rectum cancer(1 case),prostate cancer(1 case).PET scan was performed in 3 patients and well corresponded with diffusion weighted imaging in 2 cases,the other one was not visualized on diffusion weighted imaging.The highest ADC of malignant tumors was(1.58?2.06)?10-3mm2/s,the lowest ADC of malignant tumors was(0.88?0.74)?10-3mm2/s,the mean values of ADC of malignant tumors was(1.34?0.79)?10-3mm2/s.Conclusion DWIBS is a new method of diffusion-weighted MR,it has high spatial resolution,high contrast to noise ratio(CNR) and high SNR. This technique can be used as a powerful screening tool for tumour and evaluating the pathological lesions by measuring the values of ADC.