Intracranial hemorrhage MRI

	Intracranial hemorrhage Microchapters
Patient Information
Overview
Classification Subdural hematoma Epidural hematoma Subarachnoid hemorrhage Intraventricular hemorrhage Intraparenchymal hemorrhage
Causes
Differential Diagnosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

MRI

Fluid-attenuated inversion recovery (FLAIR) is the most sensitive MRI pulse sequence for the detection of SAH. SAH appears as high-intensity signal in normally low signal CSF spaces.
T2- and T2*-weighted images can potentially demonstrate SAH as low signal intensity in normally high-signal subarachnoid spaces.
On T1-weighted images, acute SAH may appear as intermediate- or high-intensity signal in the subarachnoid space.
MR angiography may be useful in the evaluation of aneurysms and other vascular lesions that cause SAH.

MRI is more sensitive than CT scanning in the detection of subdural hematomas because the multiplanar and superior tissue differentiation of MRI makes detection easier.

The shape of the subdural hematoma on axial images is the same crescent-shaped pattern seen on CT scan images.

The signal depends on the age of the hemorrhage and follows the signal pattern of intraparenchymal hematomas in acute and subacute cases.
Chronic subdural hematomas, which appear as isoattenuation relative to CSF on CT scans, often demonstrate increased signal intensity on T1-weighted images because of the presence of free methemoglobin, though the intensity decreases over time.