Optimization and evaluation of the signal intensity change in multisection oxygen-enhanced MR lung imaging

The behavior of the signal intensity in MRI of human lungs was investigated during inhalation of pure oxygen. Nine volunteers were examined, five using a breath-hold and four using a non-breath-hold technique. Four coronal slices were acquired in each volunteer using an inversion recovery turbo spin-echo sequence. The inversion time of the sequence was optimized for maximum contrast. Breathing of pure oxygen and room air was alternated in the volunteers. Breath-hold and non-breath-hold cases were compared. Breathing pure oxygen lead to a statistically significant signal intensity increase (up to 18%) compared to breathing room air. In addition, T₁ maps were acquired during breathing 100% oxygen and room air. Inhalation of pure oxygen reduced the mean T₁ time of the lungs from 1280 (±85) msec to 1224 (±139) msec without breath-hold and from 1219 (±176) to 1074 (±92) msec with breath-hold. Therefore, an optimized sequence and measurement protocol provided significant signal intensity changes utilizing 100% oxygen. Magn Reson Med 43:860–866, 2000. © 2000 Wiley-Liss, Inc.