Intravoxel incoherent motion diffusion-weighted imaging in the liver: comparison of mono-, bi- and tri-exponential modelling at 3.0-T.
Fiche publication
Date publication
juin 2015
Auteurs
Membres identifiés du Cancéropôle Est :
Pr PETIT Jean-Michel
Tous les auteurs :
Cercueil JP, Petit JM, Nougaret S, Soyer P, Fohlen A, Pierredon-Foulongne MA, Schembri V, Delhom E, Schmidt S, Denys A, Aho S, Guiu B
Lien Pubmed
Résumé
PURPOSE: To determine whether a mono-, bi- or tri-exponential model best fits the intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) signal of normal livers. MATERIALS AND METHODS: The pilot and validation studies were conducted in 38 and 36 patients with normal livers, respectively. The DWI sequence was performed using single-shot echoplanar imaging with 11 (pilot study) and 16 (validation study) b values. In each study, data from all patients were used to model the IVIM signal of normal liver. Diffusion coefficients (Di +/- standard deviations) and their fractions (fi +/- standard deviations) were determined from each model. The models were compared using the extra sum-of-squares test and information criteria. RESULTS: The tri-exponential model provided a better fit than both the bi- and mono-exponential models. The tri-exponential IVIM model determined three diffusion compartments: a slow (D1 = 1.35 +/- 0.03 x 10(-3) mm(2)/s; f1 = 72.7 +/- 0.9 %), a fast (D2 = 26.50 +/- 2.49 x 10(-3) mm(2)/s; f2 = 13.7 +/- 0.6 %) and a very fast (D3 = 404.00 +/- 43.7 x 10(-3) mm(2)/s; f3 = 13.5 +/- 0.8 %) diffusion compartment [results from the validation study]. The very fast compartment contributed to the IVIM signal only for b values
Référence
Eur Radiol. 2015 Jun;25(6):1541-50