Brain and cerebrospinal fluid motion: real-time quantification with M-mode MR imaging

Area of Science:

• Neuroimaging
• Biophysics
• Medical Physics

Background:

• Understanding the dynamic motion of brain parenchyma and cerebrospinal fluid (CSF) is crucial for diagnosing neurological conditions.
• Traditional imaging techniques have limitations in capturing real-time, physiological movements within the brain.
• Magnetic resonance (MR) imaging offers advanced capabilities for non-invasive physiological assessment.

Purpose of the Study:

• To evaluate the utility of real-time magnetic resonance (MR) phase imaging for assessing brain parenchyma and cerebrospinal fluid (CSF) motion.
• To visualize and quantify the dynamic movements of brain structures and CSF in vivo.

Main Methods:

• Employed a novel MR phase imaging technique utilizing repetitive 2D selective excitation and 1D imaging.
• Incorporated bipolar gradients to achieve velocity sensitivity in any spatial direction, analogous to M-mode echography.
• Acquired real-time imaging data from healthy volunteers.

Main Results:

• Observed periodic motion of the brain and CSF synchronized with the heart rate in healthy volunteers.
• Quantified ventricular squeezing with peak velocities up to 1 mm/sec and slower recoil.
• Documented respiratory-related shifts in brain stem position and displacements during Valsalva maneuvers and coughing.

Conclusions:

• Real-time MR phase imaging is effective for observing dynamic and non-periodic events related to brain and CSF motion.
• This technique provides valuable insights into the physiological dynamics of the central nervous system.
• Potential applications in diagnosing and monitoring neurological disorders characterized by abnormal fluid dynamics.