Measurement of regional lung function in rats using hyperpolarized 3helium dynamic MRI.

Published

Journal Article

Dynamic regional lung function was investigated in rats using a radial acquisition cine (RA-CINE) pulse sequence together with hyperpolarized (HP) (3)He gas delivered by a constant flow ventilator. Based on regional differences in the behavior of inspired air, the lung was conceptually divided into two regions (the major airways and the peripheral airspace) for purposes of functional analysis. To measure regional function in the major airways, a large RF flip angle (24 degrees) was applied to reduce (3)He magnetization in the peripheral airspace, and signal intensity (SI) was normalized with the projected airway diameter to estimate local airflow. Higher normalized signal intensity was observed in the left branch airway as compared to the right branch airway. To determine regional function in the peripheral airspace, a small RF flip angle (6 degrees) was used. Incremental increases of peripheral SI in successive lung images were consistent with the increase in lung volume. A new "skipping" scanning strategy using dummy frames allows a trade-off between the number of frames acquired for dynamic information, the RF flip angle, and the penetration depth of (3)He magnetization into the lung. This work provides a novel approach to simultaneously assess dynamic regional function and morphology.

Full Text

Duke Authors

Cited Authors

  • Chen, BT; Brau, ACS; Johnson, GA

Published Date

  • January 2003

Published In

Volume / Issue

  • 49 / 1

Start / End Page

  • 78 - 88

PubMed ID

  • 12509822

Pubmed Central ID

  • 12509822

International Standard Serial Number (ISSN)

  • 0740-3194

Digital Object Identifier (DOI)

  • 10.1002/mrm.10336

Language

  • eng

Conference Location

  • United States