Computed diffusion-weighted imaging using 3-T magnetic resonance imaging for prostate cancer diagnosis
To assess the efficacy of computed diffusion-weighted images (cDWIs) of b = 2000 s/mm2 (cDWI2000) generated from DWIs of b = 0 and 1000 for prostate cancer (PCa) diagnosis in comparison with that of measured original DWIs of b = 1000 (mDWI1000) and b = 2000(mDWI2000) using 3-T MRI.
Eighty patients who underwent a preoperative MRI examination, including T2WI and DWI (b = 0, 1000, 2000 s/mm2), were enrolled in this study. Four combinations of images, protocol A (T2WI alone), B (T2WI + mDWI1000), C (T2WI + mDWI2000) and D (T2WI + cDWI2000), were assessed for their diagnostic capability. Areas under the receiver operating characteristic curve (Az) and diagnostic performance were evaluated, as well as contrast ratios (CR) between cancerous and non-cancerous lesions for each DWI.
The highest CR was obtained with cDWI2000 (0.29 ± 0.16). Sensitivity, specificity, accuracy, and Az of the protocols were: A: 66.3 %, 59.4 %, 63.0 %, 0.67; B: 82.6 %, 62.0 %, 72.5 %, 0.80; C: 84.1 %, 66.5 %, 75.5 %, 0.86; D: 83.2 %, 70.0 %, 76.6 %, and 0.84, respectively The specificities and accuracies of protocol C and D were significantly higher than those of protocol B (P < 0.05).
cDWI2000 appears to be more effective than mDWI1000, and at least as effective as mDWI2000 for PCa diagnosis.
• Computed diffusion-weighted MRI with over b1000s/mm2is useful for prostate cancer detection.
• Computed DWI produces any b-value images with two different b-value images.
• DWI with computed b2000s/mm2is as valuable as DWI with measured b2000 s/mm2.
KeywordsProstate cancer Computed diffusion-weighted imaging High b-value MRI Diagnosis
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