title: A continuous-infusion dynamic MRI model at 3.0 Tesla for the serial quantitative evaluation of microvascular proliferation in an animal model of glioblastoma multiforme.
abstract: To develop a continuous-infusion dynamic MRI technique to characterize tumor-associated microvascular proliferation (MVP) in a rat brain model of glioblastoma multiforme.
  
  
  
  The proposed model assumes effects due to tumor-associated MVP (eg, vascular permeability, Ktrans; intravascular plasma fraction, vp) cannot be individually separated and solves for a single parameter (kvasc) that quantifies the T1-weighted contrast enhancement from dynamic images acquired during continuous contrast agent (CA) infusion. Untreated C6 tumor-bearing animals (N = 6) were serially imaged on postoperative days (PODs) 14 and 18 with a 3 Tesla clinical scanner utilizing a dynamic spatial and temporal resolution of 0.38 × 0.38 × 1.5 mm3and 3.47 s, respectively.
  
  
  
  An association was present between PODs 14 and 18 for median tumor kvasc(Pearson's r = 0.94, P = 0.0052) and CA concentration ([CA], derived from pre- and postcontrast R1maps; r = 0.94, P = 0.0054). On POD 18, there was a voxel-based association between kvascand [CA] within each tumor (0.45 < r < 0.82, P < 0.001). However, voxel-based subregions demonstrated a reduced association between kvascand [CA] (N = 5; -0.08 < r < 0.22, P > 0.05) or an inverse association (N = 1; r = -0.28, P = 0.001), indicating differences between locations of vascular permeability and subsequent CA pooling in tumors.
  
  
  
  The continuous-infusion method may provide a quantitative measure for characterizing and monitoring tumor-associated MVP. Magn Reson Med 78:1824-1838, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
authors.affiliation: Department of Pediatrics, Division of Medical Genetics, University of Utah, Salt Lake City, Utah, USA.|Department of Radiology, University of Utah, Salt Lake City, Utah, USA.|Department of Neurological Surgery, University of Washington, Seattle, Washington, USA.
authors.forename: Hunter R
authors.initials: HR
authors.lastname: Underhill
mesh_terms: D000818:Animals; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging; D001932:Brain Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging; D045744:Cell Line, Tumor; D003287:Contrast Media; D004195:Disease Models, Animal; D005909:Glioblastoma / Q000098:blood supply / Q000000981:diagnostic imaging; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D019047:Phantoms, Imaging; D051381:Rats; D017208:Rats, Wistar
chemical_list: D003287:Contrast Media
keywords: animal model; contrast enhancement; dynamic MRI; glioblastoma multiforme