CT Head Without IV Contrast Serial follow-up noncontrast CT of the head is useful in the patient with persistent or evolving symptoms despite medical treatment or with symptoms suggestive of propagation of thrombus. This is particularly useful in the late acute and subacute phases following initial presentation. Noncontrast CT may show sinus hyperdensity, which may be useful in early evaluation of thrombus extent; however, only 30% of noncontrast head CT examinations are abnormal in the setting of CVT [99]. CTA Neck With IV Contrast There is no relevant literature to support the use of CTA of the neck in the setting of known CVT. CTV Head With IV Contrast In the setting of known CVT, CTV of the head may be useful in assessing thrombus burden; however, there are no data to support its use in determining the duration of anticoagulation. CTV is as accurate in evaluation of CVT as MRV [101,106]. CTV has high spatial resolution and is not affected by typical MRI artifacts that may complicate thrombus imaging. CTV may be useful when MRV is degraded and accurate measurement of thrombus extent is desired or when thrombus involves hypoplastic dural sinuses or cortical branches. MRA Head Without and With IV Contrast There is no relevant literature to support the use of contrast-enhanced MRA of the head in the setting of known CVT. MRA Neck Without and With IV Contrast There is no relevant literature to support the use of MRA of the neck in the setting of known CVT. MRA Neck With IV Contrast There is no relevant literature to support the use of MRA of the neck in the setting of known CVT. MRI Head Perfusion With IV Contrast Some studies demonstrate a possible role for perfusion imaging in prognostic evaluation of the ischemic penumbra in the setting of known CVT [100]. CTP is not typically performed, however, in ongoing surveillance imaging in the absence of changes in clinical status.
Cerebrovascular Diseases Stroke and Stroke Related Conditions PCAs. CT Head Without IV Contrast Serial follow-up noncontrast CT of the head is useful in the patient with persistent or evolving symptoms despite medical treatment or with symptoms suggestive of propagation of thrombus. This is particularly useful in the late acute and subacute phases following initial presentation. Noncontrast CT may show sinus hyperdensity, which may be useful in early evaluation of thrombus extent; however, only 30% of noncontrast head CT examinations are abnormal in the setting of CVT [99]. CTA Neck With IV Contrast There is no relevant literature to support the use of CTA of the neck in the setting of known CVT. CTV Head With IV Contrast In the setting of known CVT, CTV of the head may be useful in assessing thrombus burden; however, there are no data to support its use in determining the duration of anticoagulation. CTV is as accurate in evaluation of CVT as MRV [101,106]. CTV has high spatial resolution and is not affected by typical MRI artifacts that may complicate thrombus imaging. CTV may be useful when MRV is degraded and accurate measurement of thrombus extent is desired or when thrombus involves hypoplastic dural sinuses or cortical branches. MRA Head Without and With IV Contrast There is no relevant literature to support the use of contrast-enhanced MRA of the head in the setting of known CVT. MRA Neck Without and With IV Contrast There is no relevant literature to support the use of MRA of the neck in the setting of known CVT. MRA Neck With IV Contrast There is no relevant literature to support the use of MRA of the neck in the setting of known CVT. MRI Head Perfusion With IV Contrast Some studies demonstrate a possible role for perfusion imaging in prognostic evaluation of the ischemic penumbra in the setting of known CVT [100]. CTP is not typically performed, however, in ongoing surveillance imaging in the absence of changes in clinical status.