In this article, we will discuss the Role of CT scan and Carotid Doppler study in Diagnosis of Acute Ischemic Stroke. So, let’s get started.
CT scan
This is now widely available and is indicated in usually all patients with stroke or transient ischemic attack (TIA). CT scan will demonstrate the site of the lesion and will also differentiate between hemorrhage and infarction. It will detect an unexpected space occupying lesion, i.e. tumor, abscess, hematoma, parasitic cyst. It can also detect surrounding edema and less consistently hemorrhagic infarction. It cannot differentiate early (within 6 hours) ischemic tissue from normal tissue, nor can it detect cases of early infarction (less than 24 hours) hence CT scan obtained within first few hours of infarction may be normal. Detection rate increases over the succeeding few days and 90% of all infarcts are detected at one week. CT scan with angiography (contrast CT scan) will differentiate enhancing from non-enhancing lesions.
Carotid Doppler study
This ultrasound study is of value in screening for carotid artery disease (TIA, reversible ischemic neurological deficit). In skilled hands, it is highly useful in demonstrating internal carotid artery occlusion.