TY  - JOUR
A1  - Triphan, Simon M. F.
A1  - Jobst, Bertram J.
A1  - Anjorin, Angela
A1  - Sedlaczek, Oliver
A1  - Wolf, Ursula
A1  - Terekhov, Maxim
A1  - Hoffmann, Christian
A1  - Ley, Sebastian
A1  - Düber, Christoph
A1  - Biederer, Jürgen
A1  - Kauczor, Hans-Ulrich
A1  - Jakob, Peter M.
A1  - Wielpütz, Mark O.
T1  - Reproducibility and comparison of oxygen-enhanced T\(_1\) quantification in COPD and asthma patients
JF  - PLoS ONE
N2  - T\(_1\) maps have been shown to yield useful diagnostic information on lung function in patients with chronic obstructive pulmonary disease (COPD) and asthma, both for native T\(_1\) and ΔT\(_1\), the relative reduction while breathing pure oxygen. As parameter quantification is particularly interesting for longitudinal studies, the purpose of this work was both to examine the reproducibility of lung T\(_1\) mapping and to compare T\(_1\) found in COPD and asthma patients using IRSnapShotFLASH embedded in a full MRI protocol. 12 asthma and 12 COPD patients (site 1) and further 15 COPD patients (site 2) were examined on two consecutive days. In each patient, T\(_1\) maps were acquired in 8 single breath-hold slices, breathing first room air, then pure oxygen. Maps were partitioned into 12 regions each to calculate average values. In asthma patients, the average T\(_{1,RA}\) = 1206ms (room air) was reduced to T\(_{1,O2}\) = 1141ms under oxygen conditions (ΔT\(_1\) = 5.3%, p < 5⋅10\(^{−4})\), while in COPD patients both native T\(_{1,RA}\) = 1125ms was significantly shorter (p < 10\(^{−3})\) and the relative reduction to T\(_{1,O2}\) = 1081ms on average ΔT\(_1\) = 4.2%(p < 10\(^{−5}\)). On the second day, with T\(_{1,RA}\) = 1186ms in asthma and T\(_{1,RA}\) = 1097ms in COPD, observed values were slightly shorter on average in all patient groups. ΔT\(_1\) reduction was the least repeatable parameter and varied from day to day by up to 23% in individual asthma and 30% in COPD patients. While for both patient groups T\(_1\) was below the values reported for healthy subjects, the T\(_1\) and ΔT\(_1\) found in asthmatics lies between that of the COPD group and reported values for healthy subjects, suggesting a higher blood volume fraction and better ventilation. However, it could be demonstrated that lung T\(_1\) quantification is subject to notable inter-examination variability, which here can be attributed both to remaining contrast agent from the previous day and the increased dependency of lung T\(_1\) on perfusion and thus current lung state.
KW  - Medicine
KW  - Chronic obstrusive pulmonary disease
KW  - Asthma
KW  - Oxygen
KW  - Magnetic resonance imaging
KW  - Breathing
KW  - Pulmonary imaging
KW  - Protons
KW  - Diagnostic medicine
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171833
VL  - 12
IS  - 2
ER  -