[T1 maps and O2-enhanced MRT of the diseased lung. Emphysema, fibrosis, mucoviscidosis].
OBJECTIVE
Gas exchange is the primary function of the lung and the transport of oxygen plays a key role in pulmonary physiology and pathophysiology.


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.


CONCLUSIONS
Results published in the literature indicate that T1 mapping and oxygen enhanced MR are promising new methods in functional imaging of the lung.
Universitätsklinik für Radiodiagnostik, Medizinische Universität Wien. alfred.stadler@meduniwien.ac.at
A
A
Stadler
L
L
Stiebellehner
P M
PM
Jakob
J F T
JF
Arnold
A A
AA
Bankier
D000280:Administration, Inhalation; D003287:Contrast Media / Q000008:administration & dosage; D003550:Cystic Fibrosis / Q000175:diagnosis*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008168:Lung / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D010100:Oxygen / Q000008:administration & dosage; D011656:Pulmonary Emphysema / Q000175:diagnosis*; D011658:Pulmonary Fibrosis / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003287:Contrast Media; D010100:Oxygen