CT Head Perfusion CT head perfusion imaging may identify the progression of known underlying intracranial or extracranial atherosclerotic disease, which could predict recurrent or new ischemic events in the future. CTP may be used for surveillance examination in the cases in which known vascular lesions are present. In the absence of a known steno- occlusive lesion, there is no literature to support the use of CTP in surveillance imaging of prior ischemic strokes. In patients with complete extracranial internal carotid artery occlusion in whom CTP can be used to determine its hemodynamic effect [17]. However, selection of patients with carotid occlusion for revascularization based on hemodynamic compromise does not improve outcome [18]. CT Head With IV Contrast There is no role for IV contrast in the CT evaluation of evolving or subacute infarct. In fact, contrast enhancement within previously undocumented subacute infarcts can paradoxically cause confusion with other more aggressive brain lesions or hemorrhagic conversion of prior infarcts. CT Head Without and With IV Contrast There is no role for IV contrast in the CT evaluation of evolving or subacute infarct. In fact, contrast enhancement within previously undocumented subacute infarcts can paradoxically cause confusion with other more aggressive brain lesions or hemorrhagic conversion of prior infarcts. CT Head Without IV Contrast Noncontrast CT of the head can be useful in the early surveillance of ischemic strokes to evaluate for complications such as hemorrhagic conversion, mass effect, and herniation when clinically indicated. Moreover, noncontrast CT is more sensitive for the evaluation of the extent of ischemic changes on follow-up imaging of strokes than in the hyperacute setting [67]. In circumstances in which ongoing surveillance is warranted, CT is usually preferred due to its quick repeatability and ease of comparison to prior examinations.
Cerebrovascular Diseases Stroke and Stroke Related Conditions PCAs. CT Head Perfusion CT head perfusion imaging may identify the progression of known underlying intracranial or extracranial atherosclerotic disease, which could predict recurrent or new ischemic events in the future. CTP may be used for surveillance examination in the cases in which known vascular lesions are present. In the absence of a known steno- occlusive lesion, there is no literature to support the use of CTP in surveillance imaging of prior ischemic strokes. In patients with complete extracranial internal carotid artery occlusion in whom CTP can be used to determine its hemodynamic effect [17]. However, selection of patients with carotid occlusion for revascularization based on hemodynamic compromise does not improve outcome [18]. CT Head With IV Contrast There is no role for IV contrast in the CT evaluation of evolving or subacute infarct. In fact, contrast enhancement within previously undocumented subacute infarcts can paradoxically cause confusion with other more aggressive brain lesions or hemorrhagic conversion of prior infarcts. CT Head Without and With IV Contrast There is no role for IV contrast in the CT evaluation of evolving or subacute infarct. In fact, contrast enhancement within previously undocumented subacute infarcts can paradoxically cause confusion with other more aggressive brain lesions or hemorrhagic conversion of prior infarcts. CT Head Without IV Contrast Noncontrast CT of the head can be useful in the early surveillance of ischemic strokes to evaluate for complications such as hemorrhagic conversion, mass effect, and herniation when clinically indicated. Moreover, noncontrast CT is more sensitive for the evaluation of the extent of ischemic changes on follow-up imaging of strokes than in the hyperacute setting [67]. In circumstances in which ongoing surveillance is warranted, CT is usually preferred due to its quick repeatability and ease of comparison to prior examinations.