CT Imaging Computed Tomography/Computed Tomography Angiography/ Perfusion in Acute Ischemic Stroke and Vasospasm

In conclusion, CT, CTA, and CTP play crucial roles in the comprehensive evaluation and management of AIS, aneurysmal SAH, and vasospasm. Each modality provides unique and complementary information that assists clinicians in making critical treatment decisions. NCCT scans are often the first step in neurologic imaging, being readily available, fast, and effective in distinguishing ischemic stroke from hemorrhagic stroke. It can show early signs of ischemia such as loss of grey-white differentiation and localized parenchymal edema as well as identify the distribution and degree of SAH and its possible sequela including hydrocephalus. NCCT can guide clinicians in identifying indications or contraindications for certain therapies. CTA expands on this by offering a detailed view of the cerebral vasculature. In ischemic stroke, this allows for the identification of LVOs, evaluation of collateral circulation, and detection of potential sources of emboli. In the setting of aneurysmal SAH, CTA allows for the identification of intracranial aneurysms and the detection of vasospasm. This information is crucial as it can directly impact therapeutic decisions, such as the consideration of endovascular treatment. CTP further enhances the evaluation by providing functional data about CBF. This can help delineate the extent of the core infarct from the penumbra (the area of brain tissue that is at risk but not yet infarcted), assisting in the selection of patients who may benefit from acute interventions even beyond the conventional time windows ( Figs. 8 and 9 ). In concert, these imaging modalities provide a robust evaluation of AIS and hemorrhagic stroke, each contributing to a larger picture of the patient's cerebrovascular status, guiding immediate management and therapeutic strategies, and influencing prognosis. It is important, however, to interpret their findings in the context of the overall clinical scenario, considering the patient's symptoms, medical history, and physical examination. A comprehensive, multidimensional approach is crucial in the management of acute ischemic and hemorrhagic stroke to ensure the best possible patient outcomes.