Evaluation of Traumatic Subarachnoid Hemorrhage Using Susceptibility-Weighted Imaging

Two cases with Sylvian fissure SAH. Case 1: CT (A) shows a large amount of hemorrhage accumulating in the lateral part of the left Sylvian fissure (white arrow). SWI (B) shows only a small amount of hemorrhage deposited along the Sylvian fissure. SWI phase image (C) shows a similar pattern as in B without obvious aliasing. Case 2: CT (D) does not show high attenuation at the right Sylvian fissure (white arrow). SWI (E) shows a small amount of hemorrhage (black arrow). Phase image (F) shows aliasing effect (white >arrow).

SAH of the prepontine cistern: CT (A) shows high attenuation in the pontine cistern (black arrow). SWI (B) shows very dark signal intensity at the same location with CSF signal intensity surrounding (white arrow). SWI phase image (C) shows aliasing (white arrow).

High attenuation of the tentorium on CT with different signals on SWI on 3 different patients. Case 1: CT (A) shows high attenuation of the tentorium (white arrow). SWI (B) shows irregular hemorrhagic signal intensity on top of the tentorium and in between the cortex of vermis of the cerebellum (black arrow). Phase image (C) shows aliasing effect (white arrow). Case 2: CT (D) shows high attenuation of the tentorium (white arrow). SWI (E) shows bulging dark signal intensity along the tentorium. SWI magnitude image (F) shows 2 smooth lines at the edge of the hemorrhage, indicating subdural hematoma. Case 3: CT (G) shows high attenuation of the tentorium (white arrow). SWI (H) and phase image (I) show no hemorrhage at the tentorial area at all. (The small foci of dark signal intensity near the tentorium in H are microhemorrhages.)

Two cases with intraventricular hemorrhage. Case 1: CT (A) shows a calcified choroid plexus (long arrow) and hemorrhage (short arrow) in the left posterior horn of the lateral ventricle. SWI (B) shows hemorrhage in both sides of the posterior horn with distinct fluid levels (black arrows) below that are blood. Case 2: CT (C) does not show intraventricular hemorrhage, but only 2 calcified choroid plexus. SWI (D) shows a very small amount of hemorrhage in both posterior horns of the lateral ventricle (arrows).

A and B are the SWI and phase image from a healthy volunteer, which show the normal sulci, veins, and falx. Note the interhemispheric fissure has CSF and therefore appears slightly brighter than WM in the phase image. C and D represent a TBI patient showing 1 sulcus filled with blood, creating a typical triangle sign. Additionally, a crescent-shaped subdural hematoma along the right convexity is seen. E and F are 2 other TBI cases showing a similar triangle sign in the paramedian sulci.

A normal volunteer's tentorium appears as isointense on SWI (A) and slightly hyperintense (diamagnetic) on the SWI phase image (B).