Leukoaraiosis, also referred as ischemic demyelination, is a radiological term given to a bilateral and either patchy or diffuse pattern of brain white matter hypodensity on CT or hyperintensity on T2 MRI that are probably related to chronic small vessel disease 1,3-4. It is commonly observed on brain CT scans of elderly people, and it is a finding related to vascular dementia.
It results from arteriosclerotic changes in the deep penetrating vessels supplying the deep white matter and periventricular regions that lack collateral supply. Lacunar infarcts in the basal ganglia occur due to the same reason. Histology from these lesions show atrophy of axons and decreased myelin.
Pathogenesis and, especially, its clinical significance are still incompletely understood 3,5.
History and etymology
The term comes from the Greek (leuko = white and araios = rarefaction) and was first proposed by Vladimir Hachinski, a Ukrainian-born Canadian neurologist 6.
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- 2. Amar K, Lewis T, Wilcock G et-al. The relationship between white matter low attenuation on brain CT and vascular risk factors: a memory clinic study. Age Ageing. 1995;24 (5): 411-5. Age Ageing (link) - Pubmed citation
- 3. Helenius J, Soinne L, Salonen O et-al. Leukoaraiosis, ischemic stroke, and normal white matter on diffusion-weighted MRI. Stroke. 2002;33 (1): 45-50. doi:10.1161/hs0102.101228 - Pubmed citation
- 4. Pantoni L, Garcia JH. Pathogenesis of leukoaraiosis: a review. Stroke. 1997;28 (3): 652-9. doi:10.1161/01.STR.28.3.652 - Pubmed citation
- 5. Geerlings MI, Appelman AP, Vincken KL et-al. Association of white matter lesions and lacunar infarcts with executive functioning: the SMART-MR study. Am. J. Epidemiol. 2009;170 (9): 1147-55. doi:10.1093/aje/kwp256 - Pubmed citation
- 6. Hachinski VC, Potter P, Merskey H. Leuko-araiosis: an ancient term for a new problem. Can J Neurol Sci. 1987;13 (4 Suppl): 533-4. Pubmed citation