Table 5. Microstructural damage and atrophy in MS and NMOSD.

Features			MS	NMOSD
Microstructural damage
	Present		Yes	Yes
	Affecting the normal-appearing tissue		Yes	Controversial
	Type of abnormalities
		Axonal damage	Yes	Potentially
		Demyelination	Yes	Controversial
	Distribution		Diffuse (CSF-in gradient)	Diffuse or restricted to secondary neurodegeneration
Atrophy
	Present		Yes	Yes
	Distribution
		White matter	Yes	Controversial
		Grey matter	Yes	Controversial
		Cortex	Yes	Yes (secondary neurodegeneration)
		Hippocampus	Yes	Yes
		Thalamus	Yes	Yes

MS = multiple sclerosis, NMOSD = neuromyelitis optica spectrum disorders, CSF = cerebrospinal fluid