Lacunes And Large Perivascular Spaces In A Community-based Population Comparative MRI Study

Background and Purpose Lacunes and perivascular spaces,common seen in general population with a similar signal as CSF,are both small fluid-filled cavities on brain MRI.According to histopathological and neuroimaging studies,most of the perivascular spaces are less than lacunes;but in clinical practice,many of the cavity lesions larger than 3mm in diameter are not lacunes,but large perivascular spaces.Up to now,there is a dearth of literature on spatial distribution and clinical profiles of large perivascular spaces.We assume that the pathogenesis of lacunes and large perivascular spaces is different.Through assessing the number and distribution,we investigated the prevalence,risk factors,correlation with other imaging changes(white matter hyperintensity,cerebral microbleed,brain atrophy,and intracranial vascular stenosis)and clinical prognosis of lacunes and large perivascular spaces in a community-based population.Methods There are 1844 participants from 5 villages in Shunyi District,Beijing enrolled.Baseline characteristics and major cardiovascular risk factor were recorded.Finally,1232 participants with good quality of brain MRI image were collected.Patients were assessed by the form of face-to-face and telephone follow-up for new events in stroke and coronary heart disease.The lucune,white matter hyperintensity volume,cerebral microbleed,perivascular space severity and large perivascular space,brain volume and intracranial artery stenosis were assessed by trained raters on brain MRI.The lacunes and large perivascular spaces were traced and masked with MRICron software,and then registered to the standard space to construct the lesion probability map for comparision.Finally,multivariate logistic regression model was applied to assess the risk factors of lacunes and large perivascular spaces and their correlation with brain imaging changes.Results This study finally analyzed 1232 subjects,with an average age of 55.1 years(SD 9.7 years)and a male ratio of 37.3%.The main results were as follows:1).The prevalence of lacunes in non-stroke cummunity population was 14.0%(173/1232),while the prevalence of large perivascular spaces was 19.0%(234/1232);As was shown in lesion probability map,large perivascular spaces were predominant in the lower third of basal ganglia;while lacunes were more common seen in the subcortical white matter,basal ganglia and brain stem.2).After adjusting for age and sex,the risk factors of age,male gender,hypertension and diabetes were independently associated with lacune;while age and ApoE genotype with allele ε4 were associated with L-PVS.3).During 2.3 years’follow-up,there were 23 stroke events were observed in subjects over 35 years old.Subejects with lacune had a higher risk of incident stroke compared with those without lacunes on MRI,with HR 8.69(95%Cl 3.13,24.14),whereas subjects with large perivascular spaces had no prominent higher risk of incident stroke.4).The appearance of lacunes was associated with white matter hyperintensity,brain atrophy,cerebral microbleed,and stenosis of intracranial vessels;while the appearance of large perivascular spaces was not related to any other radiological changes other than lacunes.Conclusion Lacunes and large perivascular spaces are both common in the general population.Besides the disagreement in spatial distribution,there are differences in risk factors and incident risk for stroke,as well as the correlation with other imaging changes.Lacunes and large perivascular spaces may bear different pathogenesis and clinical prognostic significance.