The Selection Of The B Value Of DWI In The Diagnosis Of Prostate Cancer By Biparameter MRI Was Discussed Based On PI-RADS V2

Objective:To explore a b-value of DWI sequence in the Biparameter MRI based on PI-RADS V2 to obtain the best diagnosis of prostate cancer,so as to provide the corresponding data basis for improving the examination and scoring protocol of dual-parameter MRI scheme,so as to promote the wide implementation of dual-parameter MRI as a screening tool.Methods:1.Study on the improvement of PI-RADS V2 in the diagnosis of prostate cancer by Biparameter MRI28 of prostate cancer and 34 of prostate lesions was confirmed by biopsy pathology.Three radiologists with different years of experience(A<1,B:5,C:10 years of abdominal MRI diagnostic experience)were used to blind evaluate the images of the above 62 lesions(including T2WI and B value of1000s/mm~2DWI)in two different protocols(empirical diagnosis and PI-RADS V2 diagnosis).Kappa consistency test was used to analyze the consistency among the observers.The ROC curves of 3 patients'empirical diagnosis and PI-RADS V2 diagnosis were drawn with the pathological results of total resection or puncture of prostate as the gold standard,the area under the curve was calculated,and the sensitivity,specificity,accuracy,positive and negative predictive values of prostate cancer were calculated.2.Discuss the selection of b value of DWI based on PI-RADS V2Two experienced radiologists(B:5,C:10 years of abdominal MRI diagnostic experience)performed blind evaluation the imaging images of the above 62 lesions(including DWI with T2WI and B value of 2000 and3000s/mm~2,respectively).In addition to the above diagnosis results with the b-value of 1000s/mm~2,ROC curves for diagnosis of three different b-value examination schemes were drawn with the pathological results of total resection or puncture of the prostate as the gold standard,the area under the curves was calculated,and the sensitivity,specificity,accuracy,positive and negative predictive values of prostate cancer were calculated.Kappa consistency test was used to analyze the consistency among observers.Results:1.Study on the improvement of PI-RADS V2 in the diagnosis of prostate cancer by two-parameter MRIThe results of radiologists with different years of experience were highly consistent,and the kappa value of pairwise doctors was AB:0.748.AC:0.729;BC:0.767.The areas under the ROC curve of the 3 patients with the experience diagnosis and pi-rads V2 in the diagnosis of prostate cancer were 0.661,0.774,0.899 and 0.865,respectively.The diagnostic accuracy of doctor C with high seniority was the highest,followed by pi-rads V2.2.Discuss the selection of b value of DWI based on PI-RADS V2When the b value was 1000,2000 or 3000s/mm~2,the Kappa value of the two doctors'PI-RADS V2 score was 0.767,0.832 and 0.787,respectively.The area under the ROC curve of ultra-high b-value(2000,3000s/mm~2)Biparameter MRI scheme for the diagnosis of prostate cancer was greater than that of the traditional b-value(1000s/mm~2)scheme.When the b-value was 2000s/mm~2,the diagnostic sensitivity,specificity,accuracy,negative predictive value and positive predictive value were the highest.Conclusion:1.The repeatability of PI-RADS V2 is excellent,which can improve the diagnostic level of prostate cancer in the inexperienced low and middle experience and thus reduce the difference in the diagnostic level of prostate cancer among radiologists with different seniority when applied to the Biparameter MRI scheme.2.When the b value was 2000s/mm~2,DWI had the highest diagnostic efficacy for prostate cancer.To sum up:The b-value of 2000s/mm~2Bp-MRI program combined with PI-RADS V2 has the best performance in the diagnosis of prostate cancer,which can meet the needs of the diagnosis of prostate cancer,shorten the examination time,reduce the cost of examination,and protect patients from the harm of contrast agents.Therefore,it is worth promoting.