Cerebral oxygen utilization analyzed by the use of oxygen-17 and its nuclear magnetic resonance

In vivo17O NMR approaches for brain study at high field

“…In vivo 17 O approaches can be potentially applied to measuring and imaging two important physiological parameters, namely CMRO 2 and CBF. 6,8,14,16,[37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54] The 17 O NMR approaches for in vivo determinations of CMRO 2 and CBF involve the measurement of (i) the amount of 17 O-labeled water metabolically generated from the inhaled 17 O 2 gas through the oxidative pathway, and (ii) the washout rate of the 17 O-labeled water tracer introduced by a bolus injection, respectively. In terms of methodology, there is a close similarity between the in vivo 17 O approaches and PET approaches, especially for CBF measurements.…”

“…68 The time courses of the signal changes were successfully applied to quantify and image CBF in a wide range of CBF values induced by hypercapnia and hypocapnia in animals. 39,70 The subsequent studies applied the indirect 17 O approaches for imaging the metabolic H 2 17 O water generated from 17 O-labeled oxygen gas, which was introduced either by inhalation 40 or through artificial blood. 71 The proton signal changes detected in these studies should relate to the cerebral oxidative metabolism and could be potentially linked to CMRO 2 .…”

Simplified Methods for Calculating Cerebral Metabolic Rate of Oxygen Based on 17O Magnetic Resonance Spectroscopic Imaging Measurement during a Short 17O2 Inhalation

“…However, this is a complex measurement. It requires independent determinations of cerebral H 2 15 O content, CBF, and H 2 15 O present in the arterial supply to the brain (the arterial input function) (Mintun et al, 1984); in addition, it is necessary to experimentally determine (Mintun et al, 1984) or make assumptions (Ohta et al, 1992) (Arai et al, 1990(Arai et al, , 1991Fiat and Kang, 1992;Mateescu et al, 1989;Pekar et al, 1991Pekar et al, , 1995Zhu et al, 2002). This is analogous to the PET approach.…”

17O relaxation time and NMR sensitivity of cerebral water and their field dependence

“…Most of these studies were based on indirect measurements that exploited, using different strategies, the effect of 17 O on the transverse spin relaxation time (T 2 ) of water protons (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11). The proton T 2 for the H 2 17 O molecule is known to be shorter than that of protons in H 2 16 O due to the 1 H- 17 O scalar coupling (12).…”