Intravoxel incoherent motion diffusion-weighted imaging of the pancreas: Characterization of benign and malignant pancreatic pathologies.
To evaluate the diagnostic value of apparent diffusion coefficient (ADC) and intravoxel incoherent motion (IVIM) parameters in differentiating patients with either a normal pancreas (NP), pancreatic ductal adenocarcinoma (PDAC), neuroendocrine tumor (NET), solid pseudopapillary tumor (SPT), acute pancreatitis (AcP), vs. autoimmune pancreatitis (AIP).



In all, 84 pathologically confirmed pancreatic tumors (60 PDACs, 15 NETs, 9 SPTs), 20 pancreatitis (13 AcPs, 7 AIPs), and 30 NP subjects underwent IVIM diffusion-weighted imaging using 10 b-values (0-900 sec/mm2) at 1.5T. The ADC, pure molecular diffusion coefficient (Dslow), perfusion fraction (f), and perfusion-related diffusion coefficient (Dfast) were calculated and compared using a Kruskal-Wallis test and post-hoc Dunn procedure. Receiver operating characteristic (ROC) analysis was performed to assess diagnostic performance.



The f and Dfastof the PDAC were significantly lower than that of the NP (f = 0.10 vs. 0.24; Dfast= 42.21 vs. 71.74 × 10-3mm2/sec; P < 0.05). In ROC analysis, f showed the best diagnostic performance (area-under-the-curve, 0.919) among all parameters in differentiating PDAC from NP (P ≤ 0.001). The f values of AcP (0.11) and AIP (0.13) and the Dfastvalues of SPT (20.48 × 10-3mm2/sec) and AcP (24.49 × 10-3mm2/sec) were significantly lower compared with NP (f = 0.24; Dfast= 71.74 × 10-3mm2/sec; P < 0.05). For NET, the f (0.21) was significantly higher than that of PDAC (0.10, P < 0.01).



Perfusion-related parameters f and Dfastare more helpful in characterizing pancreatic diseases than ADC or Dslow. The PDCA, SPT, AcP, and AIP were characterized by reduced f and Dfastvalues compared with normal pancreas. The f value might help in differentiating between PDAC and NET.



3 J. Magn. Reson. Imaging 2017;45:260-269.
Department of Radiology, Ajou University Hospital, Suwon, South Korea.
Bohyun
B
Kim
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Seung Soo
SS
Lee
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Yu Sub
YS
Sung
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Hyunhee
H
Cheong
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Jae Ho
JH
Byun
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Hyoung Jung
HJ
Kim
Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
Jin Hee
JH
Kim
D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009038:Motion; D010179:Pancreas / Q000000981:diagnostic imaging* / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D010195:Pancreatitis / Q000000981:diagnostic imaging* / Q000473:pathology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
diffusion-weighted imaging; intravoxel incoherent motion; pancreas; pancreatic neoplasm; pancreatitis