Journal of neuroimaging : official journal of the American Society of Neuroimaging
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Practice Guideline
American Society of Neurophysiologic Monitoring and American Society of Neuroimaging joint guidelines for transcranial doppler ultrasonic monitoring.
The American Society of Neurophysiologic Monitoring (ASNM) and American Society of Neuroimaging (ASN) Guidelines Committees formed a joint task force and developed guidelines to assist in the use of transcranial Doppler (TCD) monitoring in the surgical and intensive care settings. Specifically, these guidelines: (1) delineate the objectives of TCD monitoring; (2) characterize the responsibilities and behaviors of the sonographer during monitoring; (3) describe methodological and ethical issues uniquely relevant to monitoring. ⋯ We agree with the guidelines of other professional societies regarding the technical and professional qualifications of individuals responsible for TCD signal acquisition and interpretation (Class III evidence, Type C recommendation). On the basis of current clinical literature and scientific evidence, TCD monitoring is an established monitoring modality for the: (1) assessment of cerebral vasomotor reactivity and autoregulation; (2) documentation of the circle of Willis functional status; (3) identification of cerebral hypo- and hyperperfusion, recanalization and re-occlusion; and (4) detection of cerebral emboli (Class II and III evidence, Type B recommendation).
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Three-dimensional (3D) ultrasound imaging is a new technique that maximizes the information and image quality of traditional 2-dimensional (2D) B-mode scanning. The aim of this study was to evaluate the ability of the 3D ultrasound technique to characterize ulcerated atherosclerotic carotid plaque. ⋯ 3D ultrasound reliably characterized the surface morphology of atherosclerotic carotid plaques. A trend of superiority of 3D ultrasound over 2D was found in detecting ulcers of carotid artery plaque.
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White matter lesions (WMLs) are age-related manifestations of ischemic cerebrovascular disease and increase the risk for Alzheimer's disease (AD). The apolipoprotein E (ApoE) ɛ4 allele is a risk factor for late onset AD and has been related to low cerebrospinal fluid (CSF) Aβ42 levels and to cerebrovascular disease. The present study analyzed the relationship between WMLs, ApoE-ɛ4 genotype, and low CSF Aβ42. ⋯ A high WML load may interact with the ApoE-ɛ4 genotype and increase the risk for reduced CSF Aβ42 in patients attending a memory clinic.
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Visual disability is common in multiple sclerosis, but its relationship to abnormalities of the optic tracts remains unknown. Because they are only rarely affected by lesions, the optic tracts may represent a good model for assessing the imaging properties of normal-appearing white matter in multiple sclerosis. ⋯ Optic-tract diffusion abnormalities are associated with retinal damage, suggesting that both may be related to optic-nerve injury, but do not appear to contribute strongly to visual disability in multiple sclerosis.
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Patients with cardioembolic ischemic stroke from nonvalvular atrial fibrillation (NVAF) are candidates for long-term anticoagulation. This study examines the prevalence of cerebral microbleeds (MBs) in stroke patients with NVAF. ⋯ In contrast to studies reflecting a high incidence of MBs in stroke patients of various subtypes, MBs occurred less frequently in patients with cardioembolic acute ischemic stroke associated with NVAF. In patients with severe SVD or repeated cerebrovascular events, special caution should be taken regarding oral anticoagulation.