Effects of ozone exposure in rat lungs investigated with hyperpolarized 3 He MRI.

Purpose: To investigate the effects of subchronic ozone exposure on rat lung ventilation using hyperpolarized (HP) (3)He MRI.

Materials And Methods: A total of 24 Sprague-Dawley rats, distributed in one control group and four groups exposed to 0.5 ppm ozone concentration for two days or six days, either continuously (22 hours/day) or alternatingly (12 hours/day).

Quantitative measurements of regional lung ventilation using helium-3 MRI in a methacholine-induced bronchoconstriction model.

Purpose: To demonstrate ventilation changes in an animal model of methacholine-induced bronchoconstriction using hyperpolarized (HP) helium-3 (He-3) MRI.

Materials And Methods: Bronchoconstriction was induced in 11 healthy rats using an intravenous injection of methacholine. The He-3 was laser-polarized using a custom-built system.

Dynamic 3He imaging for quantification of regional lung ventilation parameters.

Dynamic ventilation imaging using laser-polarized (3)He has a promising potential for elucidating the physiology and physiopathology of the lungs. In this study, a methodological approach is proposed for the assessment and quantification of local ventilation parameters. High-temporal-resolution coronal ventilation image series were obtained with a projection-reconstruction (PR) sequence combined with the sliding-window technique.

Helium3 polarization using spin exchange technique: application to simultaneous pulmonary ventilation/perfusion imaging in small animals.

Rationale And Objectives: To develop a simple and robust helium3 polarization system dedicated to small animal imaging. To demonstrate the potential of helium3 imaging for pulmonary ventilation and perfusion studies.

Methods: A home-built polarization system based on spin-exchange technique was used.