PURPOSE:To evaluate which mathematical model (monoexponential, biexponential, statistical, kurtosis) fits best to the diffusion-weighted signal in prostate magnetic resonance imaging (MRI).
MATERIALS AND METHODS: 24 prostate 3-T MRI examinations of young volunteers (YV, n=8), patients with biopsy proven prostate cancer (PC, n=8) and an aged matched control group (AC, n=8) were included. Diffusion-weighted imaging was performed using 11 b-values ranging from 0 to 800 s/mm2.
RESULTS: Monoexponential apparent diffusion coefficient (ADC) values were significantly (P< .001) lower in the peripheral (PZ) zone (1.18±0.16 mm2/s) and the central (CZ) zone (0.73±0.13 mm2/s) of YV compared to AC (PZ 1.92±0.17 mm2/s; CZ 1.35±0.21 mm2/s). In PC ADCmono values (0.61±0.06 mm2/s) were significantly (P< .001) lower than in the peripheral of central zone of AC. Using the statistical analysis (Akaike information criteria) in YV most pixels were best described by the biexponential model (82%), the statistical model, respectively kurtosis (93%) each compared to the monoexponential model. In PC the majority of pixels was best described by the monoexponential model (57%) compared to the biexponential model.
CONCLUSION: Although a more complex model might provide a better fitting when multiple b-values are used, the monoexponential analyses for ADC calculation in prostate MRI is sufficient to discriminate prostate cancer from normal tissue using b-values ranging from 0 to 800 s/mm2.
Written by:
Quentin M, Blondin D, Klasen J, Lanzman RS, Miese FR, Arsov C, Albers P, Antoch G, Wittsack HJ. Are you the author?
Department of Diagnostic and Interventional Radiology, University Dusseldorf, Medical Faculty, D-40225 Dusseldorf, Germany.
Reference: Magn Reson Imaging. 2012 Jul 19. Epub ahead of print.
doi: 10.1016/j.mri.2012.04.025
PubMed Abstract
PMID: 22819178
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