Cortical Microinfarcts Detected In Vivo on 3 Tesla MRI

Wong

et al. 2016

Stroke

Self Cite

Background and Purpose— It was recently demonstrated that cerebral microinfarcts (CMIs) can be detected in vivo using 3.0 tesla (T) magnetic resonance imaging. We investigated the prevalence, risk factors, and the longitudinal cognitive consequence of cortical CMIs on 3.0T magnetic resonance imaging, in patients with ischemic stroke or transient ischemic attack. Methods— A total of 231 patients undergoing 3.0T magnetic resonance imaging were included. Montreal Cognitive Assessment was used to evaluate global cognitive functions and cognitive domains (memory, language, and attention visuospatial and executive functions). Cognitive changes were represented by the difference in Montreal Cognitive Assessment score between baseline and 28-month after stroke/transient ischemic attack. The cross-sectional and longitudinal associations between cortical CMIs and cognitive functions were explored using ANCOVA and regression models. Results— Cortical CMIs were observed in 34 patients (14.7%), including 13 patients with acute (hyperintense on diffusion-weighted imaging) and 21 with chronic CMIs (isointense on diffusion-weighted imaging). Atrial fibrillation was a risk factor for all cortical CMIs (odds ratio, 4.8; 95% confidence interval, 1.5–14.9; P =0.007). Confluent white matter hyperintensities was associated with chronic CMIs (odds ratio, 2.8; 95% confidence interval, 1.0–7.8; P =0.047). The presence of cortical CMIs at baseline was associated with worse visuospatial functions at baseline and decline over 28-month follow-up (β=0.5; 95% confidence interval, 0.1–1.0; P =0.008, adjusting for brain atrophy, white matter hyperintensities, lacunes, and microbleeds). Conclusions— Cortical CMIs are a common finding in patients with stroke/transient ischemic attack. Associations between CMI with atrial fibrillation and white matter hyperintensities suggest that these lesions have a heterogeneous cause, involving microembolism and cerebral small vessel disease. CMI seemed to preferentially impact visuospatial functions as assessed by a cognitive screening test.

Section: Neuropsychological Assessmentmentioning

confidence: 87%

Section: Discussionmentioning

confidence: 99%

Section: Neuropsychological Assessmentmentioning

confidence: 99%

See 1 more Smart Citation

Risk Factors and Cognitive Relevance of Cortical Cerebral Microinfarcts in Patients With Ischemic Stroke or Transient Ischemic Attack

Wang

Wong

et al. 2016

Stroke

Self Cite

“…Despite lower signal-to-noise ratio and resolution, it seems feasible to recognize chronic gliotic CMIs on 3-tesla MRI as well. 5,[26][27][28] Hemorrhagic CMIs cannot currently be distinguished from primary hemorrhages, both will be regarded as cerebral microbleeds on in vivo MRI. Juxtacortical hyperintense lesions should best be discarded.…”

Section: Discussionmentioning

confidence: 99%

The Spectrum of MR Detectable Cortical Microinfarcts: A Classification Study with 7-Tesla Postmortem MRI and Histopathology

J Cereb Blood Flow Metab

Zwanenburg

Rozemüller

et al. 2015

Self Cite

Cerebral microinfarcts (CMIs) are common neuropathologic findings in aging and dementia. We explored the spectrum of cortical CMIs that can be visualized with 7T magnetic resonance imaging (MRI). Thirty-three coronal brain slices of 11 individuals with neuropathologically confirmed dementia were subjected to a high-resolution postmortem 7T MRI protocol. First, we identified all visible small (⩽5 mm) intracortical and juxtacortical lesions on postmortem MRI. Lesions were classified as CMI or nonCMI based on histology, and their MR features were recorded. Thirty lesions were identified on the initial MRI evaluation, of which twenty-three could be matched with histology. Histopathology classified 12 lesions as CMIs, all of which were located intracortically. On the basis of their MR features, they could be classified as chronic gliotic CMIs-with or without cavitation or hemorrhagic components-and acute CMIs. Eleven MRI identified lesions were not of ischemic nature and most commonly enlarged or atypically shaped perivascular spaces. Their MRI features were similar to gliotic CMIs with or without cavitation, but these 'CMI mimics' were always located juxtacortically. 7T postmortem MRI distinguishes different histopathologic types of cortical CMIs, with distinctive MR characteristics. On the basis of our findings, we propose in vivo rating criteria for the detection of intracortical CMIs.

“…Optimization and standardization of assessment protocols for these lesions will support rapid implementation of robust and valid CMI detection in cohort studies throughout the world. This will enable a widespread evaluation of the clinical relevance of CMIs in the context of aging, cerebrovascular disease, and dementia in future clinical studies, both cross-sectional as well as longitudinal 9,10 .…”

Section: Discussionmentioning

confidence: 99%

Assessing Cortical Cerebral Microinfarcts on High Resolution MR Images

Biessels

Luijten

et al. 2015

JoVE

Self Cite

Cerebral microinfarcts are frequent findings in the post-mortem human brain, and are related to cognitive decline and dementia. Due to their small sizes it is challenging to study them on clinical MRI scans. It was recently demonstrated that cortical microinfarcts can be depicted with MRI scanners using high magnetic field strengths (7T). Based on this experience, a proportion of these lesions is also visible on lower resolution 3T MRI. These findings were corroborated with ex vivo imaging of post-mortem human brain tissue, accompanied by histopathological verification of possible cortical microinfarcts.Here an ex vivo imaging protocol is presented, for the purpose of validating MR observed cerebral microvascular pathology with histological evaluation. Furthermore, guidelines are provided for the assessment of cortical microinfarcts on both in vivo 7T and 3T MR images. These guidelines provide researchers with a tool to rate cortical microinfarcts on in vivo images of larger patient samples, to further unravel their clinical relevance in cognitive decline and dementia, and establish these lesions as a novel biomarker of cerebral small vessel disease. Video LinkThe video component of this article can be found at