A measurement setup for direct 17O MRI at 7 T

An efficient breathing system was designed for direct 17O MRI to perform oxygen metabolism studies of the human brain. The breathing system consists of a demand oxygen delivery device for 17O2 supply and a custom‐built re‐breathing circuit with pneumatic switching valve. To efficiently deliver the 17O gas to the alveoli of the lungs, the system applies short gas pulses upon an inspiration trigger via a nasal cannula. During and after 17O2 administration, the exhaled gas volumes are stored and filtered in the re‐breathing section to make the most efficient use of the rare 17O gas. In an inhalation experiment, 2.2 ± 0.1 L of 70%‐enriched 17O2 were administered to a healthy volunteer and direct 17O 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 17O water. Magn Reson Med, 2011. © 2011 Wiley‐Liss, Inc.

[1]  S. Meiboom,et al.  NUCLEAR MAGNETIC RESONANCE STUDY OF THE PROTON TRANSFER IN WATER , 1961 .

[2]  Hanzhang Lu,et al.  Noninvasive quantification of whole‐brain cerebral metabolic rate of oxygen (CMRO2) by MRI , 2009, Magnetic resonance in medicine.

[3]  Ravinder Reddy,et al.  Mapping of cerebral oxidative metabolism with MRI , 2010, Proceedings of the National Academy of Sciences.

[4]  H. Gudbjartsson,et al.  The rician distribution of noisy mri data , 1995, Magnetic resonance in medicine.

[5]  T. L. Davis,et al.  Calibrated functional MRI: mapping the dynamics of oxidative metabolism. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[6]  A. Hopkins,et al.  Oxygen‐17 compounds as potential NMR T2 contrast agents: Enrichment effects of H217O on protein solutions and living tissues , 1987, Magnetic resonance in medicine.

[7]  Peter Börnert,et al.  Three‐dimensional radial ultrashort echo‐time imaging with T2 adapted sampling , 2006, Magnetic resonance in medicine.

[8]  Wolfhard Semmler,et al.  Sodium MRI using a density‐adapted 3D radial acquisition technique , 2009, Magnetic resonance in medicine.

[9]  Yuki Shinohara,et al.  Interindividual Variations of Cerebral Blood Flow, Oxygen Delivery, and Metabolism in Relation to Hemoglobin Concentration Measured by Positron Emission Tomography in Humans , 2010, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[10]  Yi Zhang,et al.  In vivo 17O NMR approaches for brain study at high field , 2005, NMR in biomedicine.

[11]  Richard S. J. Frackowiak,et al.  Cerebral blood flow, blood volume and oxygen utilization. Normal values and effect of age. , 1990, Brain : a journal of neurology.

[12]  Ian C. Atkinson,et al.  Feasibility of mapping the tissue mass corrected bioscale of cerebral metabolic rate of oxygen consumption using 17-oxygen and 23-sodium MR imaging in a human brain at 9.4T , 2010, NeuroImage.

[13]  D. Tailor,et al.  Mechanical Ventilator for Delivery of 17O2 in Brief Pulses , 2008, The open biomedical engineering journal.

[14]  Janusz Hankiewicz,et al.  17O magnetic resonance imaging of the human brain , 2004, Neurological research.

[15]  B. Tiep,et al.  Pulsed nasal and transtracheal oxygen delivery. , 1990, Chest.

[16]  A. Adams,et al.  Characteristics of demand oxygen delivery systems: maximum output and setting recommendations. , 2004, Respiratory care.

[17]  A. Mackay,et al.  In vivo measurement of T2 distributions and water contents in normal human brain , 1997, Magnetic resonance in medicine.

[18]  Ravinder R Regatte,et al.  Proton MRI of metabolically produced H2 17O using an efficient 17O2 delivery system , 2004, NeuroImage.

[19]  J. Pekar,et al.  In Vivo measurement of cerebral oxygen consumption and blood flow using 17O magnetic resonance imaging , 1991, Magnetic resonance in medicine.

[20]  M. Mintun,et al.  Brain oxygen utilization measured with O-15 radiotracers and positron emission tomography. , 1984, Journal of nuclear medicine : official publication, Society of Nuclear Medicine.