Diffusion weighted imaging of prostate and rectal wall: comparison of biexponential and monoexponential modelled diffusion coefficients
Riches S, Hawtin K, deSouza N
Institute of Cancer Research & Royal Marsden NHS Trust
Diffusion weighted (DW) MRI is increasingly being used to identify prostate cancer, particularly within the central gland (PCG) where T2-W imaging has poor contrast between benign and malignant nodules. In a study of 50 patients, endorectal single shot echo-planar DW-MRI with 11 b-values ranging from 0 800 s/mm2 was analysed with two different models. A biexponential model could not adequately describe the central gland, but identified a perfusion component in the peripheral zone and rectal tissues, allowing a true diffusion coefficient to be calculated which was statistically different from the monoexponentially derived values of the apparent diffusion coefficient.