Perfusion maps of the whole liver based on high temporal and spatial resolution contrast-enhanced MRI (4D THRIVE): feasibility and initial results in focal liver lesions.
OBJECTIVE
To prospectively evaluate a new imaging sequence (4D THRIVE) for whole liver perfusion in high temporal and spatial resolution. Feasibility of parametric mapping and its potential for characterizing focal liver lesions (FLLs) are investigated.


METHODS
Fifteen patients suspected for colorectal liver metastases (LMs) were included. Parametric maps were evaluated qualitatively (ring-enhancement and lesion heterogeneity) and compared to three-phased contrast-enhanced MRI. Quantitative analysis was based on average perfusion values of entire FLLs. Reference standard comprised surgery with histopathology or follow-up imaging. Fisher's exact test was used for qualitative and Kruskal-Wallis test for quantitative analysis.


RESULTS
In total 29 LMs, 17 hemangiomas and 4 focal nodular hyperplasias were evaluated. FLLs could be differentiated by qualitative assessment of parametric maps respectively three-phased contrast-enhanced MRI (Fisher's p<0.001 for comparisons between LMs and hemangiomas and LMs and FNHs for both ring-enhancement and lesion heterogeneity) rather than by quantitative analysis of parametric maps (Chi-square for Kep=0.33 (p=0.847) and Chi-square for Kel=1.35 (p=0.509)).


CONCLUSIONS
This preliminary study shows potential of 4D THRIVE for whole liver imaging enabling calculation of parametric maps. Qualitative rather than quantitative analysis was accurate for differentiating malignant and benign FLLs.
Department of Radiology, AZ St.-Jan Brugge-Oostende AV, Bruges, Belgium. kenneth.coenegrachts@azbrugge.be
Kenneth
K
Coenegrachts
Johan
J
Ghekiere
Vincent
V
Denolin
Beck
B
Gabriele
Gwen
G
Hérigault
Marc
M
Haspeslagh
Peter
P
Daled
Shandra
S
Bipat
Jaap
J
Stoker
Hans
H
Rigauts
D000465:Algorithms; D015179:Colorectal Neoplasms / Q000473:pathology*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008113:Liver Neoplasms / Q000473:pathology* / Q000556:secondary*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity