MRI estimation of global brain oxygen consumption rate

Area of Science:

• Neuroscience
• Medical Imaging
• Physiology

Background:

• Global cerebral metabolic rate of oxygen (CMRO(2)) is crucial for evaluating brain health.
• Current methods for CMRO(2) measurement can be invasive or time-consuming.
• Accurate assessment of CMRO(2) is vital for diagnosing conditions related to cerebral metabolism dysregulation.

Purpose of the Study:

• To develop and validate a rapid, noninvasive method for quantifying global CMRO(2).
• To simultaneously measure venous oxygen saturation and cerebral blood flow.
• To assess the clinical utility of the developed technique for in vivo applications.

Main Methods:

• Utilized magnetic resonance susceptometry-based oximetry to measure venous oxygen saturation in the superior sagittal sinus.
• Employed phase-contrast magnetic resonance imaging to determine the average cerebral blood inflow rate.
• Simultaneously acquired data for rapid CMRO(2) quantification.

Main Results:

• Achieved a short acquisition time of approximately 30 seconds.
• Obtained average values in healthy subjects: venous HbO(2) 64%+/-4%, cerebral blood flow 45.2+/-3.2 mL/100g/min, and global CMRO(2) 127+/-7 µmol/100g/min.
• Demonstrated good agreement with previously reported literature values.

Conclusions:

• The developed noninvasive MRI technique is robust and reproducible for in vivo CMRO(2) measurement.
• The method's speed and accuracy make it suitable for clinical settings and studying temporal CMRO(2) variations.
• This technique offers a valuable tool for assessing pathologies linked to cerebral metabolism disorders.