### Abstract

Rational and Objectives: Pulmonary partial pressure of oxygen (pO_{2}) and oxygen depletion rate (R) are two important parameters of lung function. The dependence of hyperpolarized ^{3}He (HP ^{3}He) T_{1} on local oxygen concentration provides the basis for high-resolution mapping of the regional distributions of pO_{2} and R in the lung. Although the oxygen-sensitive HP ^{3}He magnetic resonance imaging technique has been applied in human subjects and several animal species, reproducibility studies are rarely reported in the literature. This work presents a preliminary reproducibility study on a pig model. In this study, important scan parameters, such as measurement timing and flip angle, are optimized to minimize the noise-induced measurement uncertainty. Materials and Methods: In the in vivo study, five normal pigs and one diseased pig with simulated pulmonary emboli were scanned with a small flip angle gradient echo sequence. The pulmonary oxygen measurement was repeated two to four times in each pig. In each measurement, a series of six images were acquired with optimal timing and flip angle. The parametric maps were generated using a bin-based data processing procedure that applied the multiple regression fitting method to extract the pO_{2} and R. Variations of global mean, percentiles, and regions of interest were calculated from the maps to analyze reproducibility. Results: The global statistical analyses show that average variation of global mean is 10.7% for pO_{2} and 23.8% for R, and that the average variation of percentiles (10th, 25th, 50th, 75th, and 90th) and interquartile range is 14.8% for pO_{2} and 30.4% for R. The region-of-interest analysis on the manually selected regions shows that the average variation of mean is 12.6% for pO_{2} and 21.9% for R. Conclusion: In this work, a preliminary study on the reproducibility of measuring pO_{2} and R with HP ^{3}He magnetic resonance imaging on a pig model is presented.

Original language | English (US) |
---|---|

Pages (from-to) | 702-712 |

Number of pages | 11 |

Journal | Academic Radiology |

Volume | 15 |

Issue number | 6 |

DOIs | |

State | Published - Jun 2008 |

### Fingerprint

### Keywords

- Hyperpolarized He MRI
- multiple regression fitting method
- oxygen depletion rate
- pulmonary partial pressure of oxygen
- reproducibility study
- scan parameter optimization

### ASJC Scopus subject areas

- Radiology Nuclear Medicine and imaging

### Cite this

*Academic Radiology*,

*15*(6), 702-712. https://doi.org/10.1016/j.acra.2008.01.024

**Measurement of Pulmonary Partial Pressure of Oxygen and Oxygen Depletion Rate with Hyperpolarized Helium-3 MRI : A Preliminary Reproducibility Study on Pig Model.** / Yu, Jiangsheng; Rajaei, Sheeva; Ishii, Masaru; Law, Michelle; Emami, Kiarash; Woodburn, John M.; Kadlecek, Stephen; Vahdat, Vahid; Rizi, Rahim R.

Research output: Contribution to journal › Article

*Academic Radiology*, vol. 15, no. 6, pp. 702-712. https://doi.org/10.1016/j.acra.2008.01.024

}

TY - JOUR

T1 - Measurement of Pulmonary Partial Pressure of Oxygen and Oxygen Depletion Rate with Hyperpolarized Helium-3 MRI

T2 - A Preliminary Reproducibility Study on Pig Model

AU - Yu, Jiangsheng

AU - Rajaei, Sheeva

AU - Ishii, Masaru

AU - Law, Michelle

AU - Emami, Kiarash

AU - Woodburn, John M.

AU - Kadlecek, Stephen

AU - Vahdat, Vahid

AU - Rizi, Rahim R.

PY - 2008/6

Y1 - 2008/6

N2 - Rational and Objectives: Pulmonary partial pressure of oxygen (pO2) and oxygen depletion rate (R) are two important parameters of lung function. The dependence of hyperpolarized 3He (HP 3He) T1 on local oxygen concentration provides the basis for high-resolution mapping of the regional distributions of pO2 and R in the lung. Although the oxygen-sensitive HP 3He magnetic resonance imaging technique has been applied in human subjects and several animal species, reproducibility studies are rarely reported in the literature. This work presents a preliminary reproducibility study on a pig model. In this study, important scan parameters, such as measurement timing and flip angle, are optimized to minimize the noise-induced measurement uncertainty. Materials and Methods: In the in vivo study, five normal pigs and one diseased pig with simulated pulmonary emboli were scanned with a small flip angle gradient echo sequence. The pulmonary oxygen measurement was repeated two to four times in each pig. In each measurement, a series of six images were acquired with optimal timing and flip angle. The parametric maps were generated using a bin-based data processing procedure that applied the multiple regression fitting method to extract the pO2 and R. Variations of global mean, percentiles, and regions of interest were calculated from the maps to analyze reproducibility. Results: The global statistical analyses show that average variation of global mean is 10.7% for pO2 and 23.8% for R, and that the average variation of percentiles (10th, 25th, 50th, 75th, and 90th) and interquartile range is 14.8% for pO2 and 30.4% for R. The region-of-interest analysis on the manually selected regions shows that the average variation of mean is 12.6% for pO2 and 21.9% for R. Conclusion: In this work, a preliminary study on the reproducibility of measuring pO2 and R with HP 3He magnetic resonance imaging on a pig model is presented.

AB - Rational and Objectives: Pulmonary partial pressure of oxygen (pO2) and oxygen depletion rate (R) are two important parameters of lung function. The dependence of hyperpolarized 3He (HP 3He) T1 on local oxygen concentration provides the basis for high-resolution mapping of the regional distributions of pO2 and R in the lung. Although the oxygen-sensitive HP 3He magnetic resonance imaging technique has been applied in human subjects and several animal species, reproducibility studies are rarely reported in the literature. This work presents a preliminary reproducibility study on a pig model. In this study, important scan parameters, such as measurement timing and flip angle, are optimized to minimize the noise-induced measurement uncertainty. Materials and Methods: In the in vivo study, five normal pigs and one diseased pig with simulated pulmonary emboli were scanned with a small flip angle gradient echo sequence. The pulmonary oxygen measurement was repeated two to four times in each pig. In each measurement, a series of six images were acquired with optimal timing and flip angle. The parametric maps were generated using a bin-based data processing procedure that applied the multiple regression fitting method to extract the pO2 and R. Variations of global mean, percentiles, and regions of interest were calculated from the maps to analyze reproducibility. Results: The global statistical analyses show that average variation of global mean is 10.7% for pO2 and 23.8% for R, and that the average variation of percentiles (10th, 25th, 50th, 75th, and 90th) and interquartile range is 14.8% for pO2 and 30.4% for R. The region-of-interest analysis on the manually selected regions shows that the average variation of mean is 12.6% for pO2 and 21.9% for R. Conclusion: In this work, a preliminary study on the reproducibility of measuring pO2 and R with HP 3He magnetic resonance imaging on a pig model is presented.

KW - Hyperpolarized He MRI

KW - multiple regression fitting method

KW - oxygen depletion rate

KW - pulmonary partial pressure of oxygen

KW - reproducibility study

KW - scan parameter optimization

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UR - http://www.scopus.com/inward/citedby.url?scp=43249121606&partnerID=8YFLogxK

U2 - 10.1016/j.acra.2008.01.024

DO - 10.1016/j.acra.2008.01.024

M3 - Article

VL - 15

SP - 702

EP - 712

JO - Academic Radiology

JF - Academic Radiology

SN - 1076-6332

IS - 6

ER -