PURPOSE: Gas exchange is the primary function of the lung and the transport of oxygen plays a key role in pulmonary physiology and pathophysiology. MATERIALS AND METHODS: Molecular oxygen is weakly paramagnetic, so that an increase in oxygen concentration results in shortening T1 relaxation time and thus increasing signal intensity in T1 weighted images. The calculation of parameter maps may allow deeper insights into relaxation mechanisms. T1 maps based on a snapshot FLASH sequence obtained during the inhalation of various oxygen concentrations allow the creation of an oxygen transfer function, providing a measurement of local oxygen transfer. T1 weighted single shot TSE sequences demonstrate the signal changing effects during inhalation of pure oxygen. RESULTS: The average of the mean T1 values over the entire lung during inspiration was 1,199+/-117 ms, the average of these values during expiration was 1,333+/-167 ms. T1 maps of patients with emphysema and lung fibrosis show fundamentally different values and respiratory dependence compared to healthy individuals. Oxygen enhanced MR has the potential to assess reduced diffusion capacity and decreased transport of oxygen in patients with emphysema and cystic fibrosis. DISCUSSION: Results published in the literature indicate that T1 mapping and oxygen enhanced MR are promising new methods in functional imaging of the lung.
PURPOSE: Gas exchange is the primary function of the lung and the transport of oxygen plays a key role in pulmonary physiology and pathophysiology. MATERIALS AND METHODS: Molecular oxygen is weakly paramagnetic, so that an increase in oxygen concentration results in shortening T1 relaxation time and thus increasing signal intensity in T1 weighted images. The calculation of parameter maps may allow deeper insights into relaxation mechanisms. T1 maps based on a snapshot FLASH sequence obtained during the inhalation of various oxygen concentrations allow the creation of an oxygen transfer function, providing a measurement of local oxygen transfer. T1 weighted single shot TSE sequences demonstrate the signal changing effects during inhalation of pure oxygen. RESULTS: The average of the mean T1 values over the entire lung during inspiration was 1,199+/-117 ms, the average of these values during expiration was 1,333+/-167 ms. T1 maps of patients with emphysema and lung fibrosis show fundamentally different values and respiratory dependence compared to healthy individuals. Oxygen enhanced MR has the potential to assess reduced diffusion capacity and decreased transport of oxygen in patients with emphysema and cystic fibrosis. DISCUSSION: Results published in the literature indicate that T1 mapping and oxygen enhanced MR are promising new methods in functional imaging of the lung.
Authors: Alfred Stadler; Peter M Jakob; Mark Griswold; Markus Barth; Alexander A Bankier Journal: J Magn Reson Imaging Date: 2005-06 Impact factor: 4.813
Authors: M Kveder; I Zupancic; G Lahajnar; R Blinc; D Suput; D C Ailion; K Ganesan; C Goodrich Journal: Magn Reson Med Date: 1988-08 Impact factor: 4.668
Authors: Peter M Jakob; Tungte Wang; Georg Schultz; Helge Hebestreit; Alexandra Hebestreit; Dietbert Hahn Journal: Magn Reson Med Date: 2004-05 Impact factor: 4.668