Diffusion-Weighted Magnetic Resonance Imaging for the Evaluation of Prostate Cancer: Optimal B Value at 3T.
- Author:
Ji Hyun KOO
1
;
Chan Kyo KIM
;
Dongil CHOI
;
Byung Kwan PARK
;
Ghee Young KWON
;
Bohyun KIM
Author Information
- Publication Type:Original Article
- Keywords: Diffusion-weighted MR imaging; Prostate neoplasm; Apparent diffusion coefficient; Diagnosis
- MeSH: Aged; Aged, 80 and over; Area Under Curve; Biopsy; Diagnosis, Differential; Diffusion Magnetic Resonance Imaging/*methods; Humans; Male; Middle Aged; Neoplasm Staging; Predictive Value of Tests; Prostate-Specific Antigen/blood; Prostatectomy; Prostatic Neoplasms/*diagnosis/pathology/surgery; Retrospective Studies; Sensitivity and Specificity
- From:Korean Journal of Radiology 2013;14(1):61-69
- CountryRepublic of Korea
- Language:English
- Abstract: OBJECTIVE: To retrospectively determine the optimal b value of diffusion-weighted imaging (DWI) for predicting the presence of localized prostate cancer, and to evaluate the utility of DWI under different b values in differentiating between cancers and benign prostatic tissues. MATERIALS AND METHODS: Eighty patients with suspected prostate cancer underwent MRI including DWI at 3T, followed by radical prostatectomy. DWI was examined under different b values. Apparent diffusion coefficient (ADC) maps were generated by using b = 0, and other b values of 300, 700, 1000 or 2000 s/mm2. For predicting the presence of cancers, four different ADC maps were analyzed independently by two blinded readers. ADCs were measured in benign and malignant tissues. RESULTS: For predicting the presence of 110 prostate cancers, the sensitivity and area under the curve (AUC) for an experienced reader was significantly greater at b = 1000 (85% and 0.91) than b = 300, 700 or 2000 s/mm2 (p < 0.01). For a less-experienced reader, the AUC was significantly greater at b = 700, 1000 or 2000 than b = 300 s/mm2 (p < 0.01). Mean ADCs of the cancers in sequence from b = 300 to 2000 s/mm2 were 1.33, 1.03, 0.88 and 0.68 x 10(-3) mm2/s, which were significantly lower than those of benign tissues (p < 0.001). CONCLUSION: The optimal b value for 3T DWI for predicting the presence of prostate cancer may be 1000 s/mm2.
