Neuroimaging standards for research into small vessel disease and its contribution to ageing and neurodegeneration

Abstract

SummaryCerebral small vessel disease (SVD) is a common accompaniment of ageing. Features seen on neuroimaging include recent small subcortical infarcts, lacunes, white matter hyperintensities, perivascular spaces, microbleeds, and brain atrophy. SVD can present as a stroke or cognitive decline, or can have few or no symptoms. SVD frequently coexists with neurodegenerative disease, and can exacerbate cognitive deficits, physical disabilities, and other symptoms of neurodegeneration. Terminology and definitions for imaging the features of SVD vary widely, which is also true for protocols for image acquisition and image analysis. This lack of consistency hampers progress in identifying the contribution of SVD to the pathophysiology and clinical features of common neurodegenerative diseases. We are an international working group from the Centres of Excellence in Neurodegeneration. We completed a structured process to develop definitions and imaging standards for markers and consequences of SVD. We aimed to achieve the following: first, to provide a common advisory about terms and definitions for features visible on MRI; second, to suggest minimum standards for image acquisition and analysis; third, to agree on standards for scientific reporting of changes related to SVD on neuroimaging; and fourth, to review emerging imaging methods for detection and quantification of preclinical manifestations of SVD. Our findings and recommendations apply to research studies, and can be used in the clinical setting to standardise image interpretation, acquisition, and reporting. This Position Paper summarises the main outcomes of this international effort to provide the STandards for ReportIng Vascular changes on nEuroimaging (STRIVE).

Interhemispheric characterization of small vessel disease imaging markers after subcortical infarct

“…The lack of association between the volume and location of the RSSI and the burden and location of any of the SVD markers assessed suggests that the latter appear similarly in ipsi‐ and contralateral brain hemispheres and that any problems with the vasculature are not specific to a single hemisphere in patients with a RSSI and without evidence of a previous brain trauma, in agreement with other studies (Wardlaw, Smith, Biessels, et al., 2013). The most common regions for RSSI, lacunes, and small T2*W hypointense clusters were the deep grey matter structures and their vicinities.…”

“…We followed published radiological and clinical definitions of RSSI, lacunes, WMH, old cortical infarcts, perivascular spaces, and brain microbleeds (Wardlaw, Smith, Biessels, et al., 2013). In addition, in the case of lacunes, when their intensity level on FLAIR was higher than that of CSF although still lower than the intensity level of the brain parenchyma, this was annotated for further consideration in the analyses under the assumption that these were lacunes “in formation” or “possibly lacunes” (probably confounded by MRI sequence parameters and partial volume effects due to the slice thickness).…”

“…We computationally extracted all evidence of previous hemorrhagic episodes (Bradley, 1993), and using morphology analysis annotated the volume and count of the small and round T2*W hypointense clusters that adhered to the radiological definition of microbleeds (Cordonnier, Al‐Shahi Salman, & Wardlaw, 2007; Wardlaw, Smith, Biessels, et al., 2013). Visual scores for microbleeds and perivascular spaces done by an experienced (>20 years) neuroradiologist were available from 2/3 studies from which we extracted our sample.…”

“…Recent small subcortical infarcts (RSSI) may present with acute lacunar ischemic stroke symptoms (Wardlaw, Smith, Biessels, et al., 2013) which cause about 25% of all incident ischemic strokes, equivalent to about 35,000 patients per year in the United Kingdom (Bamford, Sandercock, Jones, & Warlow, 1987; Sacco et al., 2006). In structural MRI (Magnetic Resonance Images), RSSI is clinically associated with other imaging features of brain small vessel disease (SVD), including white matter hyperintensities (WMH), lacunes, perivascular spaces, and microbleeds (Wardlaw, Smith, & Dichgans, 2013).…”

Background and distribution of lobar microbleeds in cognitive dysfunction

“…CMBs were defined as small hypointense foci <10 mm in size on SWI according to the STandards for ReportIng Vascular changes on nEuroimaging (STRIVE) consensus (Wardlaw et al., 2013). T2‐weighted images were analyzed simultaneously with SWI to rule out vessels and flow voids, which might mimic CMBs.…”