Influence of oxygen flow rate on signal and T(1) changes in oxygen-enhanced ventilation imaging.
OBJECTIVE
To investigate the optimal oxygen flow rate for oxygen-enhanced MR ventilation imaging.


METHODS
Using a cardiac-triggered nonselective inversion recovery (IR) half Fourier single-shot fast spin echo sequence, series of images were acquired with the subject alternately inhaling room air and 100% oxygen. Oxygen flow rates of 5 L/min, 10 L/min, 15 L/min, 20 L/min, and 25 L/min were studied, and signal intensity from the oxygen-enhanced ventilation images and T(1) of the lung were measured.


RESULTS
The average signal intensity was 63.0 +/- 21.0 for 5 L/min, 98.7 +/- 26.8 for 10 L/min, 133.8 +/- 20.0 for 15 L/min, 138.7 +/- 19.7 for 20 L/min, and 139.2 +/- 37.9 for 25 L/min. The average T(1)'s of the lung were 1399 msec +/- 130 msec for room air, 1314 msec +/- 101 msec for 5 L/min, 1276 msec +/- 105 msec for 10 L/min, 1207 msec +/- 71 msec for 15 L/min, 1206 msec +/- 90 msec for 20 L/min, and 1207 msec +/- 42 msec for 25 L/min.


CONCLUSIONS
The optimal flow rate is 15 L/min for oxygen-enhanced ventilation imaging.
Mai
Vu M
VM
Department of Radiology, Evanston Hospital, Evanston Northwestern Healthcare, Illinois 60201, USA. vmai@enh.org
Liu
Benjamin
B
Li
Wei
W
Polzin
Jason
J
Kurucay
Saban
S
Chen
Qun
Q
Edelman
Robert R
RR
D000328:Adult; D005260:Female; D006801:Humans; D008168:Lung / Q000033:anatomy & histology* / Q000502:physiology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000008:administration & dosage; D010101:Oxygen Consumption / Q000502:physiology*; D012123:Pulmonary Ventilation
D010100:Oxygen