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

作者：Underhill Hunter R^*

来源：Magnetic Resonance in Medicine, 2017, 78(5): 1824-1838.

DOI：10.1002/mrm.26591

• dynamic MRI
• contrast enhancement
• glioblastoma multiforme
• animal model

Purpose: To develop a continuous-infusion dynamic MRI technique to characterize tumor-associated microvascular proliferation (MVP) in a rat brain model of glioblastoma multiforme.
Methods: The proposed model assumes effects due to tumor-associated MVP (eg, vascular permeability, K-trans; intravascular plasma fraction, v(p)) cannot be individually separated and solves for a single parameter (k(vasc)) that quantifies the T-1-weighted contrast enhancement from dynamic images acquired during continuous contrast agent (CA) infusion. Untreated C6 tumor-bearing animals (N = 6) were serially imaged on post-operative days (PODs) 14 and 18 with a 3 Tesla clinical scanner utilizing a dynamic spatial and temporal resolution of 0.38 x 0.38 x 1.5mm(3) and 3.47 s, respectively.
Results: An association was present between PODs 14 and 18 for median tumor k(vasc) (Pearson's r = 0.94, P = 0.0052) and CA concentration ([CA], derived from pre-and postcontrast R-1 maps; r < 0.94, P < 0.0054). On POD 18, there was a voxelbased association between k vasc and [ CA] within each tumor (0.45< r< 0.82, P< 0.001). However, voxel-based subregions demonstrated a reduced association between k(vasc) and [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.
Conclusion: The continuous-infusion method may provide a quantitative measure for characterizing and monitoring tumor-associated MVP.

• 出版日期2017-11