Neuroimaging in vascular cognitive impairment: a state-of-the-art review.
Imaging is critical in the diagnosis and treatment of dementia, particularly in vascular cognitive impairment, due to the visualization of ischemic and hemorrhagic injury of gray and white matter. Magnetic resonance imaging (MRI) and positron emission tomography (PET) provide structural and functional information. Clinical MRI is both generally available and versatile - T2-weighted images show infarcts, FLAIR shows white matter changes and lacunar infarcts, and susceptibility-weighted images reveal microbleeds. Diffusion MRI adds another dimension by showing graded damage to white matter, making it more sensitive to white matter injury than FLAIR. Regions of neuroinflammatory disruption of the blood-brain barrier with increased permeability can be quantified and visualized with dynamic contrast-enhanced MRI. PET shows metabolism of glucose and accumulation of amyloid and tau, which is useful in showing abnormal metabolism in Alzheimer's disease. Combining MRI and PET allows identification of patients with mixed dementia, with MRI showing white matter injury and PET demonstrating regional impairment of glucose metabolism and deposition of amyloid. Excellent anatomical detail can be observed with 7.0-Tesla MRI. Imaging is the optimal method to follow the effect of treatments since changes in MRI scans are seen prior to those in cognition. This review describes the role of various imaging modalities in the diagnosis and treatment of vascular cognitive impairment.
Max Planck Institute for Metabolism Research, Gleueler str. 50, D-50931, Cologne, Germany. wdh@sf.mpg.de.
Wolf-Dieter
WD
Heiss
Department of Neurology, UNM Memory and Aging Center, MSC 11 6035, University of New Mexico, Albuquerque, NM, 87131, USA.
Gary A
GA
Rosenberg
Department of Neurology & Neurosurgery, McGill University at SMBD Jewish General Hospital and Lady Davis Institute for Medical Research, Montreal, H3T 1E2, Québec, Canada.
Alexander
A
Thiel
Department of Neurology (R.B.), University Medical Centre Ljubljana, 1000, Ljubljana, Slovenia.
Rok
R
Berlot
INSERM U1171, Degenerative and Vascular Cognitive Disorders, Université Lille 2, Lille, France.
Jacques
J
de Reuck
D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging* / Q000209:etiology; D015140:Dementia, Vascular / Q000150:complications / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D059906:Neuroimaging / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods
CT; Cerebral small vessel disease; MRI; Molecular imaging; Neuroimaging; PET; Vascular cognitive impairment