To explore whether whole-liver diffusion-weighted MRI analysis (of the apparently normal liver parenchyma) can help differentiate between patients with colorectal liver metastasis and controls without liver disease.
Ten patients with colorectal liver metastasis and 10 controls with no focal/diffuse liver disease underwent liver MRI at 1.5 T including diffusion-weighted imaging (DWI; b-values 0, 50, 100, 500, 750, 1000). Apparent diffusion coefficient (ADC) maps were calculated from the DWI images to carry out quantitative diffusion analyses. An experienced reader performed segmentation of the apparently nondiseased liver (excluding metastases/focal liver lesions) on the ADC maps. Histogram ADC parameters were calculated and compared between the patients and the controls.
The mean liver ADC was 0.95×10−3 mm2/s for the patients versus 1.03×10−3 mm2/s for the controls (P=0.42). The fifth percentile of the ADC was significantly lower for the patients compared with the controls (0.45 vs. 0.69 10−3 mm2/s, P=0.01). The SD was significantly higher in the patient group (0.30 vs. 0.22, P<0.001). Median, skewness, kurtosis, and 30th–95th percentile were not significantly different between the two groups. Areas under the receiver operator characteristics curves to differentiate patients with metastatic liver involvement from healthy controls without liver disease were 0.79 for the fifth percentile and 0.95 for the SD.
Whole-liver diffusion-weighted MRI histogram analysis showed a significant shift towards lower fifth percentile ADC values and higher SD in patients with colorectal liver metastasis compared with controls without liver disease.
Departments of aRadiology
bSurgery, Maastricht University Medical Center
cGROW School for Oncology and Developmental Biology, Maastricht, The Netherlands
dDepartment of Radiology, Alexandra Hospital, Jurong Health, Singapore, Singapore
eLaboratory of Computational Medicine, Institute of Computer Science, FORTH, Heraklion, Crete, Greece
Correspondence to Regina G.H. Beets-Tan, MD, PhD, Department of Radiology, Maastricht University Medical Center, P.O. Box 5800, 6202 AZ Maastricht, The Netherlands Tel: +31 433 876 908; fax: +31 433 876 909; e-mail: email@example.com
Received September 14, 2014
Accepted January 20, 2015