title: Four-dimensional transcatheter intraarterial perfusion (TRIP)-MRI for monitoring liver tumor embolization in VX2 rabbits.
abstract: Transcatheter intraarterial perfusion (TRIP)-MRI is an intraprocedural technique to iteratively monitor liver tumor perfusion changes during transcatheter arterial embolization (TAE) and chemoembolization (TACE). However, previous TRIP-MRI approaches using two-dimensional (2D) T(1)-weighted saturation-recovery gradient-recalled echo (GRE) sequences provided only limited spatial coverage and limited capacity for accurate perfusion quantification. In this preclinical study, a quantitative 4D TRIP-MRI technique (serial iterative 3D volumetric perfusion imaging) with rigorous radiofrequency (RF) B(1) field calibration and dynamic tissue longitudinal relaxation rate R(1) measurement is presented for monitoring intraprocedural liver tumor perfusion during TAE. 4D TRIP-MRI and TAE were performed in five rabbits with eight VX2 liver tumors (N = 8). After B(1) calibrated baseline and dynamic R(1) quantification, subsequent tissue contrast agent concentration time curves were derived. A single-input flow-limited pharmacokinetic model and peak gradient method were applied for perfusion analysis. The perfusion Frho reduced significantly from pre-TAE 0.477 (95% confidence interval [CI]: 0.384-0.570) to post-TAE 0.131 (95% CI: 0.080-0.183 ml/min/ml, P < 0.001).
authors.affiliation: Department of Radiology, Northwestern University, Chicago, Illinois 60611, USA.
authors.forename: Dingxin
authors.initials: D
authors.lastname: Wang
authors.forename: Sumeet
authors.initials: S
authors.lastname: Virmani
authors.forename: Richard
authors.initials: R
authors.lastname: Tang
authors.forename: Barbara
authors.initials: B
authors.lastname: Szolc-Kowalska
authors.forename: Gayle
authors.initials: G
authors.lastname: Woloschak
authors.forename: Reed A
authors.initials: RA
authors.lastname: Omary
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Larson
mesh_terms: D000465:Algorithms; D000818:Animals; D002404:Catheterization / Q000379:methods; D045744:Cell Line, Tumor; D004621:Embolization, Therapeutic / Q000379:methods*; D006499:Hepatic Artery / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008113:Liver Neoplasms / Q000098:blood supply / Q000175:diagnosis* / Q000628:therapy*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D010477:Perfusion / Q000379:methods; D011817:Rabbits; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity