The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme [FP7/2007-2013] / ERC grant agreement [337333]. The research of SvV and GJB is supported by a VIDI grant [91711384] from ZonMw, the Netherlands Organization for Health Research and Development.

The use of the autopsy samples and in vivo MR images for this protocol was in accordance with local regulations and approved by the local institutional review board of the University Medical Center Utrecht (UMCU).
1. MR-guided Histopathological Validation of Cortical Microinfarcts
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		<li>Based on the research question, select appropriate, preferably 10-mm t...

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CMIs have attracted increasing attention over the last few years. A growing body of evidence derived from autopsy studies has identified CMIs as important contributors to age-related cognitive decline and dementia4,5. CMIs are now detectable on 7T and also 3T MRI. 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 ...

The application of ultra-high field 7 Tesla (T) MRI in patient studies is rapidly progressing1. This paper introduces a representative application of 7T MRI in the context of cerebrovascular disease in the aging human brain. Cerebrovascular disease is a major cause of cognitive decline and dementia. This vascular contribution to dementia frequently involves the small vessels of the brain, such as arterioles, small veins, and capillaries. Hence, it is referred to as cerebral small vessel disease (SVD)2. Because the cerebral small vessels are too small to capture with conventional MRI, only the consequences of SVD - i.e., the resulting tissue injury - can be visualized. This includes white matter hyperintensities, cerebral microbleeds, and lacunar infarcts3.
Other important manifestations of SVD are cerebral microinfarcts (CMIs)4. Autopsy studies report high prevalence of CMIs in vascular dementia, and Alzheimer&#8217;s disease5. However, due to their small sizes (ranging from 50 &#181;m to a few mm) they escape detection on conventional MRI4,5. 7T MRI provides high resolution images with improved signal-to-noise-ratio and contrast, which enables the detection of certain structures and lesions beyond the detection limit of conventional MRI. This technique was therefore applied to detect CMIs. To identify possible CMIs, many in vivo 7T MRI scans were previously screened for lesions with sizes &#60;5 mm and imaging characteristics consistent with ischemic properties. Such lesions could reliably be identified in the cortex. These focal elongated lesions were hyperintense on 7T FLAIR (0.8 mm isotropic voxels), restricted to the cortex and seemed to extend from the cortical surface, hyperintense on T2 (0.7 mm isotropic voxels), and hypointense on T1 (1.0 mm isotropic voxels). It was confirmed that these lesions were cortical CMIs using an MR-guided histopathology approach in post-mortem human brain tissue6,7.
Here, the ex vivo MRI protocol is presented that was used in previous studies for the histopathological validation of cortical CMIs. Secondly, guidelines are provided for the assessment of cortical CMIs on in vivo 7T MRI. Finally, the assessment of cortical CMIs on 7T has been translated to more widely available 3T MRI, and guidelines are provided how to identify cortical CMIs on 3T MRI.

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			<td>Fomblin / Galden PFPE</td>
			<td>Solvay Solexis, Bollate, Italy</td>
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		</tr>
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			<td>7T MR system</td>
			<td>Philips Healthcare, Cleveland, OH, USA</td>
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			<td></td>
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			<td>32-channel receive head coil</td>
			<td>Nova Medical, Wilmington, MA, USA</td>
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		</tr>
		<tr>
			<td>MeVisLab</td>
			<td>MeVis Medical Solutions AG, Bremen, Germany</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

assessing cortical cerebral microinfarcts on high resolution mr images

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.

An impression of the high resolution and high image quality of an ex vivo sequence acquired at 7T is provided <a href="https://www.jove.com/files/ftp_upload/53125/53125fig4.mp4" target="_blank">here (Figure 4)</a>. This is a 3D T2* weighted ex vivo scan, with an isotropic resolution of 0.18 mm. Tissue was derived from an 84-year old demented female with pathologically proven Alzheimer&#8217;s disease and severe cerebral amyloid angiopathy (CAA). The detail of the image allows the identification of corti...

Watch this Scientific Journal Video about Assessing Cortical Cerebral Microinfarcts on High Resolution MR Images at JoVE.com

Assessing Cortical Cerebral Microinfarcts on High Resolution MR Images

A high resolution ex vivo 7T MR imaging protocol is presented, to perform MR-guided histopathological validation of microvascular pathology in post-mortem human brain tissue. Furthermore, guidelines are provided for the assessment of cortical microinfarcts on in vivo 7T as well as 3T MR images.

Cerebral microinfarcts are frequent findings in the post-mortem human brain, and are related to cognitive decline and dementia. Due to their small sizes ...

assessing-cortical-cerebral-microinfarcts-on-high-resolution-mr-images

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13.3K visualizações.  University Medical Center Utrecht.  A alta resolução ex vivo protocolo de imagiologia 7T MR é apresentado, para executar a validação histopatológico MR-guided de patologia microvascular no tecido cerebral humano post-mortem. Além disso, as orientações são fornecidas para a avaliação da microinfartos corticais sobre in vivo 7T, bem como imagens de RM 3T. 