RATIONALE AND OBJECTIVES: The aim of this work is to review hyperpolarized (HP) helium-3 (3He) magnetic resonance imaging (MRI) methods to measure regional alveolar oxygen partial pressure (P(A)O2) and oxygen depletion rate (R) in the lung. We point out limitations of the methods and suggest improvements to increase their accuracy. MATERIALS AND METHODS: P(A)O2 and R can be extracted from series of HP gas images acquired during breath hold by making use of the depolarizing effect of oxygen on HP gas. To separate oxygen-induced depolarization from other depolarizing effects, several techniques can be used. We review currently used techniques and point out their advantages and limitations. RESULTS: We show that the precision of oxygen measurements depends on a variety of parameters and can vary within the measurement volume. Accuracy of the measurement also can be influenced by diffusion of oxygen and polarized 3He and generally is different for single-slice and multislice measurements. We present numerical simulations, phantom data, and in vivo data for illustration. CONCLUSION: HP 3He MRI is a noninvasive, nonionizing, and repeatable imaging method that allows for quantitative analysis of lung function. The current techniques for measuring P(A)O2 have the potential to deliver clinically relevant functional images.
RATIONALE AND OBJECTIVES: The aim of this work is to review hyperpolarized (HP) helium-3 (3He) magnetic resonance imaging (MRI) methods to measure regional alveolar oxygen partial pressure (P(A)O2) and oxygen depletion rate (R) in the lung. We point out limitations of the methods and suggest improvements to increase their accuracy. MATERIALS AND METHODS: P(A)O2 and R can be extracted from series of HP gas images acquired during breath hold by making use of the depolarizing effect of oxygen on HP gas. To separate oxygen-induced depolarization from other depolarizing effects, several techniques can be used. We review currently used techniques and point out their advantages and limitations. RESULTS: We show that the precision of oxygen measurements depends on a variety of parameters and can vary within the measurement volume. Accuracy of the measurement also can be influenced by diffusion of oxygen and polarized 3He and generally is different for single-slice and multislice measurements. We present numerical simulations, phantom data, and in vivo data for illustration. CONCLUSION: HP 3He MRI is a noninvasive, nonionizing, and repeatable imaging method that allows for quantitative analysis of lung function. The current techniques for measuring P(A)O2 have the potential to deliver clinically relevant functional images.
Authors: Leo L Tsai; Ross W Mair; Chih-Hao Li; Matthew S Rosen; Samuel Patz; Ronald L Walsworth Journal: Acad Radiol Date: 2008-06 Impact factor: 3.173
Authors: Richard A Guyer; Michael D Hellman; Kiarash Emami; Stephen Kadlecek; Robert V Cadman; Jiangsheng Yu; Vahid Vadhat; Masaru Ishii; John MacDuffie Woodburn; Michelle Law; Rahim R Rizi Journal: Acad Radiol Date: 2008-06 Impact factor: 3.173
Authors: Hooman Hamedani; Stephen J Kadlecek; Masaru Ishii; Kiarash Emami; Nicholas N Kuzma; Yi Xin; Milton Rossman; Rahim R Rizi Journal: Magn Reson Med Date: 2013-02-04 Impact factor: 4.668
Authors: F William Hersman; Iulian C Ruset; Stephen Ketel; Iga Muradian; Silviu D Covrig; Jan Distelbrink; Walter Porter; David Watt; Jeffrey Ketel; John Brackett; Aaron Hope; Samuel Patz Journal: Acad Radiol Date: 2008-06 Impact factor: 3.173
Authors: Mark S Conradi; Dmitriy A Yablonskiy; Jason C Woods; David S Gierada; Seth-Emil T Bartel; Susan E Haywood; Christopher Menard Journal: Acad Radiol Date: 2008-06 Impact factor: 3.173