A Measurement Setup for Direct (17)O MRI at 7 T

作者：Hoffmann Stefan H; Begovatz Paul; Nagel Armin M; Umathum Reiner; Schommer Kai; Bachert Peter; Bock Michael^*

来源：Magnetic Resonance in Medicine, 2011, 66(4): 1109-1115.

DOI：10.1002/mrm.22871

• cerebral metabolic rate of oxygen consumption (CMRO(2))
• oxygen-17
• direct (17)O MRI
• non-proton MRI
• high field MRI
• brain metabolism

An efficient breathing system was designed for direct (17)O MRI to perform oxygen metabolism studies of the human brain. The breathing system consists of a demand oxygen delivery device for (17)O(2) supply and a custom-built re-breathing circuit with pneumatic switching valve. To efficiently deliver the (17)O gas to the alveoli of the lungs, the system applies short gas pulses upon an inspiration trigger via a nasal cannula. During and after (17)O(2) administration, the exhaled gas volumes are stored and filtered in the re-breathing section to make the most efficient use of the rare (17)O gas. In an inhalation experiment, 2.2 +/- 0.1 L of 70%-enriched (17)O(2) were administered to a healthy volunteer and direct (17)O MRI was performed for a total imaging time of 38 min with a temporal resolution of 50 s per 3D data set. Mapping of the maximum signal increase was carried out showing regional variations of oxygen concentration of up to 30% over the natural abundance of (17)O water. Magn Reson Med 66: 1109-1115, 2011.

• 出版日期2011-10