title: Novel imaging techniques in cerebral small vessel diseases and vascular cognitive impairment.
abstract: Dementia is a global growing concern, affecting over 35 million people with a global economic impact of over $604 billion US. With an ageing population the number of people affected is expected double over the next two decades. Vascular cognitive impairment can be caused by various types of cerebrovascular disease, including cortical and subcortical infarcts, and the more diffuse white matter injury due to cerebral small vessel disease. Although this type of cognitive impairment is usually considered the second most common form of dementia after Alzheimer's disease, there is increasing recognition of the vascular contribution to neurodegeneration, with both pathologies frequently coexisting. The aim of this review is to highlight the recent advances in the understanding of vascular cognitive impairment, with a focus on small vessel diseases of the brain. We discuss recently identified small vessel imaging markers that have been associated with cognitive impairment, namely cerebral microbleeds, enlarged perivascular spaces, cortical superficial siderosis, and microinfarcts. We will also consider quantitative techniques including diffusion tensor imaging, magnetic resonance perfusion imaging with arterial spin labelling, functional magnetic resonance imaging and positron emission tomography. As well as potentially shedding light on the mechanism by which cerebral small vessel diseases cause dementia, these novel imaging biomarkers are also of increasing relevance given their ability to guide diagnosis and reflect disease progression, which may in the future be useful for therapeutic interventions. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock.
authors.affiliation: UCL Stroke Research Centre, Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, 10-12 Russell Square, London WC1B 3EE, UK.
authors.forename: Gargi
authors.initials: G
authors.lastname: Banerjee
authors.affiliation: UCL Stroke Research Centre, Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, 10-12 Russell Square, London WC1B 3EE, UK.
authors.forename: Duncan
authors.initials: D
authors.lastname: Wilson
authors.affiliation: Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, London WC1N 3BG, UK.
authors.forename: Hans R
authors.initials: HR
authors.lastname: Jäger
authors.affiliation: UCL Stroke Research Centre, Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, 10-12 Russell Square, London WC1B 3EE, UK.
authors.forename: David J
authors.initials: DJ
authors.lastname: Werring
mesh_terms: D000818:Animals; D050379:Arteriolosclerosis / Q000000981:diagnostic imaging; D016657:Cerebral Amyloid Angiopathy / Q000000981:diagnostic imaging; D002536:Cerebral Arteries / Q000000981:diagnostic imaging*; D059345:Cerebral Small Vessel Diseases / Q000000981:diagnostic imaging*; D015140:Dementia, Vascular / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D059906:Neuroimaging / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods
keywords: Cerebral amyloid angiopathy; Cerebral small vessel disease; Dementia; Magnetic resonance imaging; Vascular cognitive impairment