Distinguishing liver haemangiomas from metastatic tumours using gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced diffusion-weighted imaging at 1.5T MRI.
BACKGROUND
The aim of this study to evaluate the effectiveness of enhanced diffusion-weighted imaging (DWI) for distinguishing liver haemangiomas from metastatic tumours (mets).


METHODS
This study included 23 patients with 27 haemangiomas and 26 patients with 46 mets. Breath-holding diffusion-weighted imaging (DWI) (b-values of 0, 50, 100, 150, 200, 400 and 800 s/mm2) were obtained before and 20 min after injection of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA). Lesion contrast-to-noise ratios (CNRs) were calculated. The data were processed using the bi-exponential model of intravoxel incoherent motion (IVIM). Receiver operating characteristic analysis was performed to compare the diagnostic performance when distinguishing haemangioma from mets.


RESULTS
The CNRs of haemangioma and mets at post-contrast enhancement increased. All IVIM parameters for liver haemangioma and mets showed no significant differences between pre- and post-contrast enhancement. The highest Azvalue of CNR and IVIM parameters occurred at a post-contrast b-value of 0 s/mm2and true diffusion (D). The highest qualitative evaluation occurred at a b-value of 800 s/mm2. The sensitivity and specificity, with a CNR of 100 or higher at a post-contrast b-value of 0 s/mm2and considered to be haemangioma, were 89% and 67% (<10 mm, 91%, 77%) respectively. The sensitivity and specificity, when D was higher than 1.4 × 10-3mm2/s, were 74% and 83% (<10 mm, 64%, 77%) respectively. The sensitivity and specificity of qualitative evaluation by enhanced DWI were 74% and 76% (<10 mm, 64%, 80%) respectively.


CONCLUSIONS
The accuracy of the CNR was highest with b = 0; however, examination at high b-values had advantages in the qualitative evaluation of some small-size lesions.
Department of Radiology, Tokyo Medical University, Tokyo, Japan. saito-k@tokyo-med.ac.jp.
Kazuhiro
K
Saito
Department of Radiology, Tokyo Medical University, Tokyo, Japan.
Nobutaka
N
Yoshimura
Department of Radiology, Tokyo Medical University, Tokyo, Japan.
Natsuhiko
N
Shirota
Department of Radiology, Tokyo Medical University, Tokyo, Japan.
Toru
T
Saguchi
Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan.
Katsutoshi
K
Sugimoto
Department of Radiology, Tokyo Medical University, Tokyo, Japan.
Koichi
K
Tokuuye
D038524:Diffusion Magnetic Resonance Imaging; D019786:Gadolinium DTPA; D006391:Hemangioma / Q000000981:diagnostic imaging* / Q000178:diet therapy; D006801:Humans; D007089:Image Enhancement / Q000592:standards*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results
C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA
diffusion-weighted imaging; gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid; haemangioma; intravoxel incoherent motion; liver metastasis