REGULAR CONTENT
Final ID
451
Type
Original Scientific Research-Oral or Pos
Authors
R Hwatar1, D Sotiriadis1, J Rhone1, G Sideris1, S Mirpour1, R Ivkov2, E Liapi1
Institutions
1Johns Hopkins University, Baltimore, MD, 2Johns Hopkins University School of Medicine, Baltimore, MD
Purpose
To validate the accuracy of wide-array CT to measure differences in regional liver and tumor perfusion in a rabbit model of liver cancer, during first-pass, contrast-enhanced wide-array CT.
Materials & Methods
7 NZW male liver VX2 bearing rabbits rabbits were anesthetized and IA injected with gold microspheres (15μm, 2 x 106 spheres, BioPal, Worcester, MA) in 30 sec, into the left ventricle under fluoroscopic guidance. while withdrawing the reference sample at 1 ml/min for 2 min, from the femoral artery. Rabbits were scanned in a wide-array 320-detector row volumetric CT scanner (Acquilion One, Toshiba, Japan) 2 hours before IA injection. Scanning parameters were: FOV=22 cm, kV=80, mA=100, slice thickness=0.5 mm, scan delay=6 sec, intermittent scanning for 74 sec (arterial phase every 2 sec, portal venous phase every 3 sec). Rabbits were injected with 1.5 ml/kg of isoosmolar CM at 1 ml/sec, followed by a saline flush. CT data were analyzed using the Toshiba CT body perfusion software and calculated tumor and hepatic perfusion values of arterial flow (AF) portal flow (PF) and perfusion index (PI). All rabbits were euthanized after microsphere injection. Samples were weighed and subsequently analyzed together with the respective reference samples using neutron activation quantification. Regional blood flow for each tissue sample was calculated according to: RBF=Fref_(Asmp/Wsmp)/Aref, where Fref is reference flow (=withdrawal rate), Asmp is activity sample, Wsmp is weight of sample and Aref is activity of reference. Pearson's correlation was used for correlating stable microsphere and CT perfusion flow values.
Results
Mean RBF for tumor was 1.15 (SD=0.74), left liver 0.48 (0.35) and right liver 0.5 (SD=0.45) ml/min/g. Mean tumor AF was 0.87 (SD=0.28), left liver AF 0.56 (SD=0.24), right liver AF 0.55 (SD=0.21) ml/min/g. CT perfusion AF values were weakly (r=0.6), but statistically significantly correlated (p=0.04) to RBF values measured with stable microspheres.
Conclusions
Wide-array CT perfusion AF values provide semiquantitative measurements of tumor regional blood flow in the rabbit model of liver cancer.
Final ID
451
Type
Original Scientific Research-Oral or Pos
Authors
R Hwatar1, D Sotiriadis1, J Rhone1, G Sideris1, S Mirpour1, R Ivkov2, E Liapi1
Institutions
1Johns Hopkins University, Baltimore, MD, 2Johns Hopkins University School of Medicine, Baltimore, MD
Purpose
To validate the accuracy of wide-array CT to measure differences in regional liver and tumor perfusion in a rabbit model of liver cancer, during first-pass, contrast-enhanced wide-array CT.
Materials & Methods
7 NZW male liver VX2 bearing rabbits rabbits were anesthetized and IA injected with gold microspheres (15μm, 2 x 106 spheres, BioPal, Worcester, MA) in 30 sec, into the left ventricle under fluoroscopic guidance. while withdrawing the reference sample at 1 ml/min for 2 min, from the femoral artery. Rabbits were scanned in a wide-array 320-detector row volumetric CT scanner (Acquilion One, Toshiba, Japan) 2 hours before IA injection. Scanning parameters were: FOV=22 cm, kV=80, mA=100, slice thickness=0.5 mm, scan delay=6 sec, intermittent scanning for 74 sec (arterial phase every 2 sec, portal venous phase every 3 sec). Rabbits were injected with 1.5 ml/kg of isoosmolar CM at 1 ml/sec, followed by a saline flush. CT data were analyzed using the Toshiba CT body perfusion software and calculated tumor and hepatic perfusion values of arterial flow (AF) portal flow (PF) and perfusion index (PI). All rabbits were euthanized after microsphere injection. Samples were weighed and subsequently analyzed together with the respective reference samples using neutron activation quantification. Regional blood flow for each tissue sample was calculated according to: RBF=Fref_(Asmp/Wsmp)/Aref, where Fref is reference flow (=withdrawal rate), Asmp is activity sample, Wsmp is weight of sample and Aref is activity of reference. Pearson's correlation was used for correlating stable microsphere and CT perfusion flow values.
Results
Mean RBF for tumor was 1.15 (SD=0.74), left liver 0.48 (0.35) and right liver 0.5 (SD=0.45) ml/min/g. Mean tumor AF was 0.87 (SD=0.28), left liver AF 0.56 (SD=0.24), right liver AF 0.55 (SD=0.21) ml/min/g. CT perfusion AF values were weakly (r=0.6), but statistically significantly correlated (p=0.04) to RBF values measured with stable microspheres.
Conclusions
Wide-array CT perfusion AF values provide semiquantitative measurements of tumor regional blood flow in the rabbit model of liver cancer.