Article

Comparison of 1 H blood oxygen level-dependent (BOLD) and 19 F MRI to investigate tumor oxygenation

Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9058, USA.
Magnetic Resonance in Medicine (Impact Factor: 3.4). 08/2009; 62(2):357-64. DOI: 10.1002/mrm.22020
Source: PubMed

ABSTRACT Fluorine-19 [(19)F] MRI oximetry and (1)H blood oxygen level-dependent (BOLD) MRI were used to investigate tumor oxygenation in rat breast 13762NF carcinomas, and correlations between the techniques were examined. A range of tissue oxygen partial pressure (pO(2)) values was found in the nine tumors while the anesthetized rats breathed air, with individual tumor pO(2) ranging from a mean of 1 to 36 torr and hypoxic fraction (HF10) (<10 torr) ranging from 0% to 75%, indicating a large intra- and intertumor heterogeneity. Breathing oxygen produced significant increase in tumor pO(2) (mean DeltapO(2) = 50 torr) and decrease in HF(10) (P < 0.01). (1)H BOLD MRI observed using a spin echo-planar imaging (EPI) sequence revealed a heterogeneous response and significant increase in mean tumor signal intensity (SI) (DeltaSI = 7%, P < 0.01). R(2)* measured by multigradient-echo (MGRE) MRI decreased significantly in response to oxygen (mean DeltaR(2)* = -4 s(-1); P < 0.05). A significant correlation was found between changes in mean tumor pO(2) and mean EPI BOLD DeltaSI accompanying oxygen breathing (r(2) > 0.7, P < 0.001). Our results suggest that BOLD MRI provides information about tumor oxygenation and may be useful to predict pO(2) changes accompanying interventions. Significantly, the magnitude of the BOLD response appears to be predictive for residual tumor HFs.

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