| Purpose: To evaluate the feasibility of intravoxel incoherent motion (IVIM)diffusion-weighted imaging in differentiating cancer lesions and noncancerous tissue in transition and peripheral zones of the prostate, and short-term test-retest and intra-observer reproducibility of IVIM-derived parameters.Materials and Methods: 23 prostate patients were scanned twice using IVIM using 12 b values (0-3000s/mm2) at 3.0T GE MR scanner. IVIM parameters (Dslow, Dfast and f)and ADC12b (using 12 b) were calculated. The one-way analysis of variance was used to compare the differences in the IVIM-derived parameters among cancer lesion, stroma BPH and glandular BPH in transitional zones, and among cancer lesion,begnign and normal peripheral zone in transitional zones. Short-term test-retest reproducibility of IVIM parameters and ADC were assessed by measuring coefficient of variation (CV)and Bland-Altman limits of agreements (BA-LA). Intra-class correlation coefficient(ICC) was calculated to evaluate intra-observer repeatability of the parameters.Results: The ADC12b,Dslow and f were significantly lower in cancer compared to stromal BPH and glandular BPH in transition zone of the prostate (all P<0.001), and also significantly lower in cancer lesions compared to benign and normal peripheral zone in peripheral zones (all P=0.000). Test-retest reproducibility was high for Dslow (CV 2.1-5.8%, BA-LA -21-21%) and ADC,2b (CV 3.1-6.1%, BA-LA -23-23%),intermediate for f (CV 4.4-10.3%, BA-LA -42-41%), and low for Dfast (CV 12.8-24.5%, BA-LA -101-89%) in cancer lesions and noncancerous tissue in transition zone of the prostate. The order of test-retest reproducibility in cancer lesions and noncancerous tissue in peripheral zone was the same as in transition zone of the prostate.In transition zone of the prostate,reproducibility of Dslow and ADC,2b was best in prostate cancer. In peripheral zone of the prostate, reproducibility of Dslow was best in prostate cancer, and ADC12b was best in normal peripheral zone. Intra-observer reproducibility was excellent for Dslow, ADC12b,and f in cancer lesion in transition zone,and cancer lesion and noncancerous tissue in peripheral zone of the prostate except for Dfast in stromal BPH and glandular BPH.Conclusions: Preliminary findings suggest that the Dslow, ADC12b,and f are significantly different between cancer lesions and noncancerous tissuses in transition and peripheral zones of the prostate.Good reproducibility for Dslow and ADC12b,intermediate for f,and poor for Dfast were observed in noncancerous tissue and cancer lesions in transition and peripheral zones of the prostate.Purpose: To evaluate the feasibility of diffusion weighted imaging (DKI) in differentiating cancer lesions and noncancerous tissue in transition and peripheral zones of the prostate, and short-term test-retest and intra-observer reproducibility of DKI-derived parameters.Materials and Methods: 23 prostate patients were scanned twice using DKI (using three b values, range 0-3000s/mm2) at 3.0T GE MR scanner. DKI parameters (K and D)were calculated. The one-way analysis of variance was used to compare the differences in the DKI-derived parameters among cancer lesion, stroma BPH and glandular BPH in transitional zones, and among cancer lesion,begnign and normal peripheral zone in transitional zones. Short-term test-retest reproducibility of DKI parameters were assessed by measuring coefficient of variation (CV) and Bland-Altman limits of agreements (BA-LA). Intra-observer repeatability of the parameters was evaluated by calculating intra-class correlation coefficient (ICC).Results: K values were significantly higher in cancer lesion compared to stromal BPH and glandular BPH (P<0.001), and D values were significantly lower in cancer lesion compared to stromal BPH and glandular BPH in transitional zones (P<0.001 ). K values were significantly higher in cancer lesion compared to benign and normal peripheral zone , and D were significantly lower in cancer lesion compared to benign and normal peripheral zone in peripheral zones of the prostate (P=0.000). Test-retest reproducibility was high for K (CV 3.5-4.7%,BA-LA -17-24%) and D (CV 5.2-5.5%,BA-LA-20-20%) in cancer lesions and noncancerous tissue in transitional zone, and also in (CV 5.1-6.3%, BA-LA-24-21%; CV 3.8-5.4%, BA-LA-21-23%)of the prostate. In transition zone of the prostate, reproducibility of K was best in prostate cancer, D was similar among cancer lesion, stomal BPH and glandular BPH. In peripheral zone of the prostate,reproducibility of K was best in prostate cancer, and D was best in normal peripheral zone. Intra-observer reproducibility was excellent for K and D in cancer lesion and noncancerous tissue in transition and peripheral zone of the prostate.Conclusions: Preliminary findings suggest that the K and D are significantly different between cancer lesions and noncancerous tissuses in transition and peripheral zones of the prostate. Good reproducibility for K and D were observed in noncancerous tissue and cancer lesions in transition and peripheral zones of the prostate.Purpose: To evaluate the differences in parameters derived from ultra-high b value diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI) between transition zone prostate cancer, stromal benign prostatic hyperplasia (BPH), and glandular BPH, and determine the role of these parameters in the differentiation transition zone prostate cancer from two types of BPH.Materials and Methods: In this retrospective study, 14 patients with 22 foci of transition zone prostate carcinomas, 23 patients with BPH (22 stromal BPH and 22 glandular BPH nodules) who underwent ultra-high b value DWI, IVIM, and DKI protocols before biopsy were analyzed. Using the parameters (ADC3000, K,Dk,Dslow,Dfast, f, and ADC 12b) were calculated for each tumor, stromal BPH and glandular BPH .The mean, standard deviation of each parameter were calculated.All the parameters in transition zone prostate carcinoma, stroma BPH and glandular BPH were compared using one-way analysis of variance.The diagnostic performances were using receiver operating characteristic (ROC) analysis. Results: K was significantly higher in transition zone prostate cancer than in stromal BPH and glandular BPH (both P<0.001).ADC3000, Dk, Dslow, f, and ADC 12b were significantly lower in transition zone prostate cancer than in stromal BPH and glandular BPH (all P<0.001). There was no significant difference in mean Dfast values between transition zone prostate cancer than in stromal BPH and glandular BPH (both P >0.05). Area under the curve for ADC3000, K, Dk, Dslow,f, and ADC12b were 0.957, 0.926, 0.942, 0.867, 0.793, and 0.894, respectively, for differentiation of transition zone prostate carcinoma from stromal BPH. Area under the curve for ADC3000, K,Dk,and ADC 12b were all 1.000, for differentiation of transition zone prostate carcinoma from glandular BPH.Conclusion: ADC3000 and Dk differ significantly between transition zone prostate carcinoma, stromal BPH, and glandular BPH, and the use of them can improve the differentiation of transition zone prostate carcinoma from stromal BPH and glandular BPH. |
