Correlations of noninvasive BOLD and TOLD MRI with pO2 and relevance to tumor radiation response. Issue 5 (27th June 2013)

• Record Type: Journal Article
• Authors: Hallac, Rami R.; Zhou, Heling; Pidikiti, Rajesh; Song, Kwang; Stojadinovic, Strahinja; Zhao, Dawen; Solberg, Timothy; Peschke, Peter; Mason, Ralph P.
• Is Part Of: Magnetic resonance in medicine. Volume 71:Issue 5(2014:May)
• Page Start: 1863
• Page End: 1873
• Publication Date: 2013-06-27
• Subjects: Nuclear magnetic resonance -- Periodicals; Electron paramagnetic resonance -- Periodicals; 616.07548
• DOI: 10.1002/mrm.24846
• Languages: English
• ISSNs: 0740-3194

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="mrm24846-sec-0001" sec-type="section"> <title>Purpose</title> <p>To examine the potential use of blood oxygenation level dependent (BOLD) and tissue oxygenation level dependent (TOLD) contrast MRI to assess tumor oxygenation and predict radiation response.</p> </sec> <sec id="mrm24846-sec-0002" sec-type="section"> <title>Methods</title> <p>BOLD and TOLD MRI were performed on Dunning R3327‐AT1 rat prostate tumors during hyperoxic gas breathing challenge at 4.7 T. Animals were divided into two groups. In Group 1 (<italic>n</italic> = 9), subsequent <sup>19</sup>F MRI based on spin lattice relaxation of hexafluorobenzene reporter molecule provided quantitative oximetry for comparison. For Group 2 rats (<italic>n</italic> = 13) growth delay following a single dose of 30 Gy was compared with preirradiation BOLD and TOLD assessments.</p> </sec> <sec id="mrm24846-sec-0003" sec-type="section"> <title>Results</title> <p>Oxygen (100%O<sub>2</sub>) and carbogen (95%O<sub>2</sub>/5%CO<sub>2</sub>) challenge elicited similar BOLD, TOLD and pO<sub>2</sub> responses. Strong correlations were observed between BOLD or <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg5f3fhsk7" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:07403194:media:mrm24846:mrm24846-math-0001" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msubsup><mml:mi>R</mml:mi><mml:mn>2</mml:mn><mml:mo>*</mml:mo></mml:msubsup></mml:mrow></mml:math></alternatives> response and quantitative <sup>19</sup>F pO<sub>2</sub> measurements. TOLD response showed a general trend with weaker correlation. Irradiation caused a significant tumor growth delay and tumors with larger changes in TOLD and <italic>R</italic><sub>1</sub> values upon oxygen breathing exhibited significantly increased tumor growth delay.</p> </sec> <sec id="mrm24846-sec-0004" sec-type="section"> <title>Conclusion</title> <p>These results provide further insight into the relationships between oxygen sensitive (BOLD/TOLD) MRI and tumor pO<sub>2</sub>. Moreover, a larger increase in <italic>R</italic><sub>1</sub> response to hyperoxic gas challenge coincided with greater tumor growth delay following irradiation. <bold>Magn Reson Med 71:1863–1873, 2014. © 2013 Wiley Periodicals, Inc.</bold></p> </sec> </abstract>