Specifically, intracranial collateral characterization may be important when considering both the initial decision to treat and treatment involving proximal embolic protection strategies. MRA Neck Without and With IV Contrast MRA of the neck is useful in the surveillance imaging of some patients with asymptomatic carotid stenosis owing to the anatomic assessment of stenosis and can be useful for treatment planning. Specifically, MRA of the neck is helpful when multivessel cerebrovascular disease or very severe stenosis is present, which might result in artifactual over or underestimation of the degree of disease by carotid Doppler, respectively [113]. Noncontrast MRA of the neck may overestimate the degree of stenosis when severe and/or near occlusive. Contrast administration can reduce the degree of overestimation of the degree of stenosis in some cases. However, contrast-enhanced and TOF MRA of the neck have similar sensitivity for the detection of >70% stenosis of the carotid when 2-D and 3-D techniques of TOF are combined [27,117]. MRA of the neck may also be useful for treatment planning. However, the anatomic definition of the surrounding structures may be inadequate for treatment planning in some cases depending on the sequences used [114]. Additionally, anatomical features of carotid plaque including intraplaque high-intensity signal on 3-D TOF source images can be useful predictors of future stroke risk, beyond assessing the degree of luminal narrowing [85,118,119]. MRA Neck Without IV Contrast MRA of the neck is useful in the surveillance imaging of some patients with asymptomatic carotid stenosis owing to the anatomic assessment of stenosis and can be useful for treatment planning. Specifically, MRA of the neck is helpful when multivessel cerebrovascular disease or very severe stenosis is present, which might result in artifactual over- or underestimation of the degree of disease by carotid Doppler, respectively [113].
Cerebrovascular Diseases Stroke and Stroke Related Conditions PCAs. Specifically, intracranial collateral characterization may be important when considering both the initial decision to treat and treatment involving proximal embolic protection strategies. MRA Neck Without and With IV Contrast MRA of the neck is useful in the surveillance imaging of some patients with asymptomatic carotid stenosis owing to the anatomic assessment of stenosis and can be useful for treatment planning. Specifically, MRA of the neck is helpful when multivessel cerebrovascular disease or very severe stenosis is present, which might result in artifactual over or underestimation of the degree of disease by carotid Doppler, respectively [113]. Noncontrast MRA of the neck may overestimate the degree of stenosis when severe and/or near occlusive. Contrast administration can reduce the degree of overestimation of the degree of stenosis in some cases. However, contrast-enhanced and TOF MRA of the neck have similar sensitivity for the detection of >70% stenosis of the carotid when 2-D and 3-D techniques of TOF are combined [27,117]. MRA of the neck may also be useful for treatment planning. However, the anatomic definition of the surrounding structures may be inadequate for treatment planning in some cases depending on the sequences used [114]. Additionally, anatomical features of carotid plaque including intraplaque high-intensity signal on 3-D TOF source images can be useful predictors of future stroke risk, beyond assessing the degree of luminal narrowing [85,118,119]. MRA Neck Without IV Contrast MRA of the neck is useful in the surveillance imaging of some patients with asymptomatic carotid stenosis owing to the anatomic assessment of stenosis and can be useful for treatment planning. Specifically, MRA of the neck is helpful when multivessel cerebrovascular disease or very severe stenosis is present, which might result in artifactual over- or underestimation of the degree of disease by carotid Doppler, respectively [113].