In Vivo Imaging of Glymphatic Circulation: Measurement of Brain Interstitial Fluid Flow During Wake and Sleep with Ultra High Performance MRI
Abstract
The demands of the military operational environment impose chronic insufficient or nonrestorative sleep for the warfighter, resulting in decreased vigilance and fatigue during daytime that can pose safety risks and threaten mission success. Studies estimate that, on average, over 70 percent of active-duty warfighters sleep less than six hours per night, and even fewer while deployed. Recent studies have shown the association between clearance of metabolic waste from the brain via the glymphatic system and sleep. While the underlying mechanisms are not yet fully understood, it is demonstrated that sleep deprivation impairs molecular clearance and that glymphatic exchange was specifically active during deep sleep. Currently, MRI is the most promising tool for imaging noninvasively and quantitatively glymphatic flow in vivo in humans. Previous mechanisms have been invasive, or unable to reach the velocity resolution to map slow-moving CSF-ISF glymphatic exchange (estimated at approx. 20 m/s). The Microstructure Anatomy Gradient for Neuroimaging with Ultrafast Scanning (MAGNUS) Magnetic resonance imaging (MRI) system addresses these limitations and is located at Walter Reed National Military Medical Center. This project aims to leverage this system to implement a MRI pulse sequence that detects glymphatic activity and measure this activity in warfighters and sleepy watch standers/shift workers.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2023
- Accession Number
- AD1212046
Entities
People
- Afis Ajala
- Isabelle Jansen
- James Demarco
- John K. Werner
- Luca Marinelli
- Nastaren Abad
- Samrawit Yalewayker
- Sonja Skeete
Organizations
- General Electric