The ARWMC Rating Scale

David Goldemund M.D.
Updated on 22/03/2024, published on 25/04/2023

ARWMC (Age-Related White Matter Changes)

this scale was designed to evaluate white matter changes (WMCs) on either CT or MRI scans
- sensitivity and reliability are higher with MRI
- differences between MRI and CT in the detection of WMCs are primarily related to lesion size – MRI is better at detecting small lesions, while medium and large lesions are equally well visualized by both modalities
- regional differences play a minor role, as ARWMC lesions occur in areas that can usually be imaged with high quality by both MRI and CT
WMCs definition:
- T2 or FLAIR MRI images – bright (hyperintense) lesions ≥ 5 mm
- NCCT – hypodense areas ≥ 5 mm
the following areas are scored (each hemisphere separately):
- frontal
- parieto-occipital
- temporal
- infratentorial, including the cerebellum
- basal ganglia (striatum, globus pallidus, thalamus, internal and external capsule, and insula)

White matter lesions (WML)
0	no lesion (including symmetrical, well-defined caps or bands)
1	focal lesions
2	an incipient confluence of lesions
3	diffuse involvement of the entire region, with or without U-fibers involvement
Basal ganglia lesions
0	no lesion
1	1 focal lesion (≥ 5 mm)
2	> 1 focal lesion
3	confluent lesions