Apperance of Stoke on Brain CT Scan

Determining Intracranial Bleed Duration

CT is the most frequently used for initial examination for imaging of intracranial hemorrhage ICH or commonly known as stroke. The appearance of an ICH will change with the passage of time. This is because the red blood cells within the hemorrhage begin to deteriorate within several hours after leaving the vasculature. The changes of appearance will depend in many factors and complex like whether the patient is anemic or whether, and to what degree of blood has mixed with cerebrospinal fluid CSF.

As a genaral rule of intracranial bleed, this hemorrhage will appear hyperdense to normal brain tissue for approximately 3 days, after which it will gradually decrease in density. This density loss begins at the periphery of the hematoma. As density minimizes, the portion of the hematoma become isodense to brain tissue. The progressive density loss continues until the entire hematoma finally becomes hypodense to brain tissue. In short, intracranial hemorrhage can be generally expected to appear hyperdense white on the image.

Apperance of Stoke from onset to 3 days

From 4 to 10 days it is likely to contain a hyperdense center surrounded by concentric areas of hyperdense and hypodense tissue.

From 11 days to 6 months it is likely to contain an isodense center surrounded by areas of hypodense tissue.

by 6 months the bleed will be hypodense to brain.

It is not the role of the radiologic technogist to interpret ct images. But however, it is important that radiologic technician know to recognize this certain potential critical pathologic changes in brain, so that when this changes is present, they can be brought to the radiologist attention. Although most patient with an intracranial hemorrhage are seen through the emergency department where images are reviewed by radiologists and reported on quickly, some patients, particularly those with less acute presentations like headache may arrive in the CT department as outpatients. In these situations, the technologist can play an important role by bringing the scan to the radiologist’s attention so that these patients receive immediate medical attention.

Why CT Scan?

CT scan is the primary imaging modality for emergent indications such as trauma and acute changes in neurologic status. For most application concerning structural imaging of the brain and skull base, nonenhanced CT is usually adequate. Intravenous contrast administration is very useful for infection and neoplasm, but in some practice this is not frequently performed because those indications most oftenly done or prompt an MRI, limiting the need for enhanced CT. But in some rare situations MRI is contraindated in patients with pacemaker or it may be unavailable, leaving enhanced CT or with contrast CT procedure is the best diagnostic option.

Radiology Profile of Stroke