Hemispheric Differences in Leukoaraiosis in Patients with Carotid Artery Stenosis: A Systematic Review

Purpose Despite the prevalence of leukoaraiosis in neuro-imaging and its link to dementia, stroke, and death, the exact pathogenesis is still unclear. While some have postulated a link between carotid artery disease and leukoaraiosis, the exact relationship between the two common clinical findings is unknown. To determine the link between carotid disease and leukoaraiosis, we performed a systematic review of interhemispheric differences in white matter disease in patients with carotid artery disease. Methods We performed a comprehensive literature search in multiple electronic databases evaluating the association of carotid artery and white matter disease using both subjective and volumetric assessment of white matter burden. The included studies examined patients with at least 30% carotid artery stenosis for white matter burden both ipsilateral and contralateral to the site of carotid artery disease. Results Of the 2920 manuscripts screened, five were included in the systematic review. One study used a volumetric analysis of the white matter burden and the others used various subjective methods. Four studies found no statistically significant relationship between carotid artery disease and ipsilateral white matter burden and one study found a significantly higher amount of white matter disease ipsilateral to carotid artery stenosis. Conclusions The mixed results in degree of hemispheric leukoaraiosis in patients with carotid artery disease indicate that no definite relationship can be established based on the existing literature. Given the complex nature of carotid artery disease, including increased risk with certain plaque components, the exact relationship requires further investigation with more rigorous research design.