Brain Lymphatics Measurements on Magnetic Resonance Images - Guidelines for Regions of Interest Placement and Intensity Scoring

The process detailed in this document is associated with a published investigation into visualising and semi-quantitatively measuring brain fluid pathways, including meningeal lymphatics, using magnetic resonance imaging (MRI) - Sennfalt et al., (2023) https://journals.sagepub.com/doi/10.1177/0271678X231179555. This document describes the procedures to be carried out for measuring signal intensity on 2D coronal T2-FLAIR MRI in regions of interest (ROIs) relevant to meningiolymphatic brain clearance as per current knowledge, using Philips Carestream DICOM viewing software (© 2022 Koninklijke Philips N.V., version 12.2.5.00397), a typical and widely used clinical radiological viewing platform. It adds 9 ROIs to the 7 ROIs described in Sennfalt et al., (2023), selected from a combination of: a) literature review and b) radiological examination of contrast enhanced regions under T2-FLAIR scans and T2-weighted scans to ensure FLAIR-specific contrast isolation. It also details the criteria for scoring the signal intensity in the ROIs.

Sennfält S, Thrippleton MJ, Stringer M, et al. Visualising and semi-quantitatively measuring brain fluid pathways, including meningeal lymphatics, in humans using widely available MRI techniques. Journal of Cerebral Blood Flow & Metabolism. 2023;43(10):1779-1795. doi:10.1177/0271678X231179555