TY - JOUR
T1 - Biexponential apparent diffusion coefficients in prostate cancer
AU - Shinmoto, Hiroshi
AU - Oshio, Koichi
AU - Tanimoto, Akihiro
AU - Higuchi, Nobuya
AU - Okuda, Shigeo
AU - Kuribayashi, Sachio
AU - Mulkern, Robert V.
PY - 2009/4/1
Y1 - 2009/4/1
N2 - Purpose: The purpose of this study was to investigate the need for biexponential signal decay modeling for prostate cancer diffusion signal decays with b-factor over an extended b-factor range. Materials and Methods: Ten healthy volunteers and 12 patients with a bulky prostate cancer underwent line scan diffusion-weighted MR imaging in which b-factors from 0 to 3000 s/mm2 in 16 steps were sampled. The acquired signal decay curves were fit with both monoexponential and biexponential signal decay functions and a statistical comparison between the two fits was performed. Results: The biexponential model provided a statistically better fit over the monoexponential model on the peripheral zone (PZ), transitional zone (TZ) and prostate cancer. The fast and slow apparent diffusion coefficients (ADCs) in the PZ, TZ and cancer were 2.9±0.2, 0.7±0.2×10-3 mm2/ms (PZ); 2.9±0.4, 0.7±0.2×10-3 mm2/ms (TZ); and 1.7±0.4, 0.3±0.1×10-3 mm2/ms (cancer), respectively. The apparent fractions of the fast diffusion component in the PZ, TZ and cancer were 70±10%, 60±10% and 50±10%, respectively. The fast and slow ADCs of cancer were significantly lower than those of TZ and PZ, and the apparent fraction of the fast diffusion component was significantly smaller in cancer than in PZ. Conclusions: Biexponential diffusion decay functions are required for prostate cancer diffusion signal decay curves when sampled over an extended b-factor range, providing additional, unique tissue characterization parameters for prostate cancer.
AB - Purpose: The purpose of this study was to investigate the need for biexponential signal decay modeling for prostate cancer diffusion signal decays with b-factor over an extended b-factor range. Materials and Methods: Ten healthy volunteers and 12 patients with a bulky prostate cancer underwent line scan diffusion-weighted MR imaging in which b-factors from 0 to 3000 s/mm2 in 16 steps were sampled. The acquired signal decay curves were fit with both monoexponential and biexponential signal decay functions and a statistical comparison between the two fits was performed. Results: The biexponential model provided a statistically better fit over the monoexponential model on the peripheral zone (PZ), transitional zone (TZ) and prostate cancer. The fast and slow apparent diffusion coefficients (ADCs) in the PZ, TZ and cancer were 2.9±0.2, 0.7±0.2×10-3 mm2/ms (PZ); 2.9±0.4, 0.7±0.2×10-3 mm2/ms (TZ); and 1.7±0.4, 0.3±0.1×10-3 mm2/ms (cancer), respectively. The apparent fractions of the fast diffusion component in the PZ, TZ and cancer were 70±10%, 60±10% and 50±10%, respectively. The fast and slow ADCs of cancer were significantly lower than those of TZ and PZ, and the apparent fraction of the fast diffusion component was significantly smaller in cancer than in PZ. Conclusions: Biexponential diffusion decay functions are required for prostate cancer diffusion signal decay curves when sampled over an extended b-factor range, providing additional, unique tissue characterization parameters for prostate cancer.
KW - Biexponential decay
KW - Diffusion
KW - MRI
KW - Prostate cancer
UR - http://www.scopus.com/inward/record.url?scp=61649122120&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=61649122120&partnerID=8YFLogxK
U2 - 10.1016/j.mri.2008.07.008
DO - 10.1016/j.mri.2008.07.008
M3 - Article
C2 - 18768281
AN - SCOPUS:61649122120
VL - 27
SP - 355
EP - 359
JO - Magnetic Resonance Imaging
JF - Magnetic Resonance Imaging
SN - 0730-725X
IS - 3
ER -