Comprehensive model for simultaneous MRI determination of perfusion and permeability using a blood-pool agent in rats rhabdomyosarcoma.
To present a new compartmental analysis model developed to simultaneously measure tissue perfusion and capillary permeability in a tumor using MRI and a macromolecular contrast medium. Rhadomyosarcomas were implanted subcutaneously in 20 rats and studied by 1.5-T MRI using a fast gradient echo sequence (2D fast SPGR TR/TE/alpha 13 ms/1.2 ms/60 degrees ) after injection of a macromolecular contrast medium. The left ventricle and tumor signal intensities were converted into concentrations and modeled using compartmental analysis, yielding tumor perfusion F, distribution volume Vdistribution, volume transfer constant Ktrans, rate constant of influx kpe, and initial extraction (fraction) E. Tumor perfusion was F=43+/-29 ml.min-1.100 g-1. The permeability study allowed the measurement of kpe=0.37+/-0.12 min-1 and Ktrans=0.01+/-0.0031 min-1. The blood volume could be assimilated to the distribution volume (Vdistribution=2.9+/-1.01%) since the capillary leakage was small. The simultaneous assessment of perfusion and permeability allowed quantification of the initial extraction (fraction) E=2.34+/-1.05%. Quantification of both tumor perfusion and capillary leakage is feasible using MRI using a macromolecular blood pool agent. The method should improve tumor characterization.
de Bazelaire
Cedric
C
Radiology Department, Saint Louis Hospital, 1 Avenue Claude Vellefaux, 75475, Paris Cedex 10, France. cedric.de-bazelaire@sls.aphp.fr
Siauve
Nathalie
N
Fournier
Laure
L
Frouin
Frederique
F
Robert
Philippe
P
Clement
Olivier
O
de Kerviler
Eric
E
Cuenod
Charles Andre
CA
D000465:Algorithms; D000818:Animals; D003198:Computer Simulation; D003287:Contrast Media; D006571:Heterocyclic Compounds; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007201:Indicator Dilution Techniques; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008955:Models, Cardiovascular; D009389:Neovascularization, Pathologic / Q000473:pathology*; D009942:Organometallic Compounds; D010539:Permeability; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D012208:Rhabdomyosarcoma / Q000098:blood supply* / Q000473:pathology*; D012680:Sensitivity and Specificity
D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate