Preliminary Study Of Intravoxel Incoherent Motion Diffusion-weighted Imaging For Diagnosing Prostate Cancer

Objectives:To investigate the difference between the parameters of thebiexponentialmodelIntravoxelIncoherentMotion Diffusion-Weighted Imaging(IVIM-DWI)in prostate cancer,benign prostatic hyperplasia and normal prostate tissues,and to evaluate the diagnostic efficiency of those parameters in diagnosing prostate cancer and benign prostatic hyperplasia in comparison to parameters of monoexponential model Diffusion Weighted Imaging(DWI).Meanwhile,the application value of IVIM-DWI parameters in assessing the malignant degree of prostate cancer will be explored.Materials and methods:Data of 62 patients suffering from urinary frequency,urgency,urinary or hematuria,and 16 healthy volunteers were collected from January 2016 to January 2017.They are all subjected to routine DWI(b=0,1500s/mm2)and IVIM-DWI(11 b values,b is 0,50,100,200,400,600,800,1000,1500,2000,3000,4000,s/mm~2)examination.Sixty-two patients with prostate disease receive pathological findings within 1 month of MRI.The Apparent diffusion coefficient(ADC),Diffusion Coefficient(D),Diffusion Coefficient From The Perfused Compartment(D*)and Perfusion Fraction(f)of the normal prostate peripheral zone(PZ)and the central gland(CG),prostate cancer,benign prostatic hyperplasia(BPH)are measured and compared.The receiver operating characteristic curveis used to evaluate the diagnostic efficiency of monoexponential and biexponential model.The correlation between Gleason score of prostate cancer and parameters of double index model is evaluated through Spearman rank correlation test.Results:A total of 62 cases are collected,including 27 cases of prostate cancer,35 cases of benign prostatic hyperplasia.The ADC value,D value,D*value and f value of prostate cancer are 0.779±0.162mm~2/s,0.382±0.080mm~2/s,5.22±2.45mm~2/s,42.3±11.8mm~2/s respectively;The ADC value,D value,D*value and f value of benign prostatic hyperplasia are 1.181±0.186mm~2/s,0.581±0.054mm~2/s,3.37±0.58mm~2/s,62.9±7.6mm~2/s respectively;The ADC value,D value,D*value and f value of normal prostate peripheral zone are about1.222±0.098 mm~2/s,0.661±0.047mm~2/s,4.21±2.88mm~2/s,and65.6±7.7mm~2/s respectively,while the normal prostate central gland is1.025±0.044mm~2/s,0.537±0.015mm~2/s,3.54±1.05 mm~2/s,54.8±5.9 mm~2/s.The ADC value,D value and f value of prostate cancer are lower than those of benign prostatic hyperplasia,normal prostate peripheral zone and central gland,therefore,the difference is statistically significant(p<0.05).In the differential diagnosis of prostate benign and malignant lesions,the D value has the largest area under the curve(0.954).There is a significant negative correlation between the D value of prostate cancer and the Gleason score(r=-0.741,p=0.000).There is a significant difference in the D value of prostate cancer between the low risk group and the middle or high risk groups(p<0.05).Conclusion:The ADC value,D value,D*value and f value of prostate cancer in the differential diagnosis of benign and malignant prostate have a certain diagnostic value,with D value having a higher diagnostic performance.Moreover,D value plays a considerable rolein assessing the degree of malignancy of prostate cancer.