Applications Of Diffusion-weighted MR Imaging Based On Mono-exponential,Bi-exponential And Stretched Exponential Models In The Diagnosis Of Prostate Cancer

Purpose To compare the value of various diffusion parameters obtained from monoexponential,biexp onential,and stretched exponential diffusion-weighted imaging(DWI)models in diagnosising prostate cancer.Materials and Methods:Retrospective analysis of puncture biopsy confirmed prostate cancer(PCa)30 cases,prostate hyperplasia(PH)27 cases of clinical data.All patients underwent T2WI?T1WI?DWI?multi-b DWI scan.According to the results of puncture pathology to determine the location of cancer or hyperplasia,with DWI and multi-b value DWI images to match.ADC,D,D*,f and DDC,a values were measured in PC group and PH group.Differences were compared using independent t test,Receiver operating characteristic(ROC)to differentiate the diagnostic efficacy,correlation analysis was performed on statistically significant parameters with good diagnostic performance.Results 1,ADC,D,DDC,a were lower in the PCa group(0.72±0.14×10-3/mm2s, 0.57±0.11×10-3/mm2s,0.71±0.14×10-3/mm2s,0.63±0.03)than in the PH group(1.14±0.13×10-3/mm2s,0.94±0.12×10-3/mm2s,1.30±0.17×10-3/mm2s,0.76±0.05)the difference was statistically significant.D*was higher in the PCa group(17.96±13.39×10-3/mm2s)than in the PH group(10.28±4.96×10-3/mm2s),the difference was statistically significant.f was slightly higher in the PCa group(0.30±0.08)than in the PH group(0.299±0.05),the difference was no statistically significant.2.D,DDC,a,ADC have higher diagnostic performance,the area under the curve(AUC)values were 0.998,0.994,0.986,0.985 respectively;the diagnostic threshold were 0.000765,0.000978,0.564,0.000874.3.ADC,D,DDC have good correlation both in PCa and PH groups.The correlation coefficient between ADC and DDC is 0.852 in PCa group,the correlation coefficient between ADC and D is 0.734 in PCa group,and the correlation coefficient between D and DDC is 0.759 in PCa group.The correlation coefficient between ADC and DDC is 0.653 in PH group,the correlation coefficient between ADC and D is 0.751 in PH group,the correlation coefficient between D and DDC is 0.590 in PH group.Conclusion DDC,a calculated from stretched exponential model,D calculated from bi-exponential model and ADC calculated from mono-exponential model in the diagnosis of prostate cancer all have high performance,stretched exponential model and bi-exponential model can provide more diagnostic information.