Improved technique for measurement of regional fractional ventilation by hyperpolarized3He MRI

Kiarash Emami, Stephen J. Kadlecek, John M. Woodburn, Jianliang Zhu, Jiangsheng Yu, Vahid Vahdat, Stephen Pickup, Masaru Ishii, Rahim R. Rizi

Research output: Contribution to journalArticlepeer-review

37 Scopus citations


Quantitative measurement of regional lung ventilation is of great significance in assessment of lung function in many obstructive and restrictive pulmonary diseases. A new technique for regional measurement of fractional ventilation using hyperpolarized 3He MRI is proposed, addressing the shortcomings of an earlier approach that limited its use to small animals. The new approach allows for the acquisition of similar quantitative maps over a shortened period and requires substantially less 3He gas. This technique is therefore a better platform for implementation in large species, including humans. The measurements using the two approaches were comparable to a great degree, as verified in a healthy rat lung, and are very reproducible. Preliminary validation is performed in a lung phantom system. Volume dependency of measurements was assessed both in vivo and in vitro. A scheme for selecting an optimum flip angle is proposed. In addition, a dead space modeling approach is proposed to yield more accurate measurements of regional fractional ventilation using either method. Finally, sensitivity of the new technique to model parameters, noise, and number of included images were assessed numerically. As a prelude to application in humans, the technique was implemented in a large animal study successfully.

Original languageEnglish (US)
Pages (from-to)137-150
Number of pages14
JournalMagnetic resonance in medicine
Issue number1
StatePublished - Jan 2010


  • Fractional ventilation
  • Hyperpolarized gas MRI
  • Mathematical models of lung
  • Quantitative pulmonary imaging
  • Regional lung ventilation

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging


Dive into the research topics of 'Improved technique for measurement of regional fractional ventilation by hyperpolarized3He MRI'. Together they form a unique fingerprint.

Cite this