Cortical cerebral microinfarcts on 3T MRI

Abstract

Cortical CMIs are a novel MRI marker of cerebrovascular disease and are independently associated with cognitive impairment and dementia. These findings provide new insights into the burden of cerebrovascular disease in cognitive impairment. Future research is needed to establish the additional etiologic and prognostic significance of cortical CMIs.

Detection, risk factors, and functional consequences of cerebral microinfarcts

“…In a 3T MRI study 28 of 238 patients who attended a memory clinic, cerebral microinfarcts were not associated with diabetes or hypertension, but were significantly associated with hyperlipidaemia. By contrast, in a study 14 of 231 patients with ischaemic stroke or transient ischaemic attack, none of these risk factors were associated with the presence of cerebral microinfarcts, whereas in a cohort 30 of 861 participants from the general population, cerebral microinfarcts were associated with hypertension. These inconsistent results indicate that identification of risk factor patterns for cerebral microinfarcts may be influenced by the setting in which they are studied, and this is an area that warrants further investigation.…”

“…A later 7T MRI study 28 of 23 patients showed that 27% of the lesions were also visible on 3T MRI scans done on the same day. Subsequently, cortical cerebral microinfarcts were examined in several studies 14,28–30 using 3T MRI. Cerebral microinfarcts have also occasionally been observed using 1·5T MRI (appendix), so this possibility should not be overlooked.…”

“…Currently, visual rating of cortical cerebral microinfarcts is time intensive (approximately 30 min per patient), and inter-rater agreement is modest (two studies reported intraclass correlation coefficients of 0·39 33 and 0·76, 26 and another study 30 reported a kappa of 0·83). Development of semi-automated detection techniques is ongoing 26,34 and would greatly improve observer reliability and the efficiency of evaluation of existing 3T MRI datasets from large cohort studies.…”

“…Both in patients who attended a memory clinic 28 and in population-based cohorts, 29,30 cerebral microinfarcts co-occur with lacunar infarcts 28,30 and the presence of cerebral microinfarcts is associated with a higher volume of white matter hyperintensities 28–30 and cerebral atrophy. 28 The presence of cerebral microinfarcts has been linked to a history of stroke in population-based cohorts, 29,30 but also among patients admitted to hospital for stroke 14,31,43 and in patients attending a memory clinic with various diagnoses, including subjective cognitive complaints, Alzheimer’s disease, and vascular dementia. 28 This association between cerebral microinfarcts and stroke might also be linked to large vessel disease, because large cortical infarcts on MRI and cerebral microinfarcts have been found to co-occur.…”

“…28 This association between cerebral microinfarcts and stroke might also be linked to large vessel disease, because large cortical infarcts on MRI and cerebral microinfarcts have been found to co-occur. 28,30 Notably, cerebral microinfarcts have been associated with intracranial stenosis in studies of patients recruited from a memory clinic 28 and in patients with ischaemic stroke, 31,43 and commonly occur ipsilateral to the stenosis. 28,43 A 2017 study 15 reported that the incidence of acute cerebral microinfarcts was 14% on diffusion-weighted imaging in patients who had carotid endarterectomy.…”