Neuro_MR_Brain: 67 M, cerebellar hemorrhages.

MRI BRAIN STROKE PROTOCOL WITH AND WITHOUT CONTRAST:

CLINICAL HISTORY: 67 years of age, Male, history of cerebellar intraparenchymal hemorrhage with concern for right cerebellar AV malformation.

FINDINGS:

BRAIN:

Parenchyma: Intraparenchymal hemorrhage and surrounding edema in the bilateral cerebellar hemispheres are unchanged. There is unchanged cerebellar swelling with effacement of the fourth ventricle, similar to the previous examination. No tonsillar herniation. There are redistributed blood products in the lateral ventricles and third ventricle.

Few scattered foci of T2/FLAIR signal hyperintensity in the white matter of the cerebral hemispheres are nonspecific and not excessive for age.

Ventricles and extra-axial spaces: There is dilatation of the lateral and third ventricles and effacement of the fourth ventricle.

Visualized paranasal sinuses: Mucosal thickening in the left sphenoid sinus.

Mastoid air cells: Trace right mastoid effusion. Left mastoid air cells are clear.

Bones: Normal.

Additional comment: None.

INTRACRANIAL ANGIOGRAM:

Anterior circulation: No flow-limiting stenosis or aneurysm.

Posterior circulation: No flow-limiting stenosis or aneurysm.

Dural venous sinuses: Flow related enhancement on MRA is noted in the right transverse sinus. Narrowing/occlusion of the proximal right transverse sinus may reflect sequela of prior thrombosis. ASL hyperintensity is noted in the right transverse/sigmoid sinuses and prominent posterior fossa venous structures.

Additional comment: The right occipital artery is enlarged. There are multiple serpiginous enhancing vessels centered in the posterior right cerebellum with hyperintensity on ASL, likely representing engorged collateral venous structures. No nidus or aneurysm is identified.

IMPRESSION:

1.  Bilateral cerebellar hemorrhages with unchanged surrounding edema and effacement of the fourth ventricle.

2.  Blood products in the lateral ventricles and third ventricle. The supratentorial ventricles appear slightly larger compared to the prior CT likely due to developing hydrocephalus.

3.  Enlarged right occipital artery, arterial signal on MRA and increased ASL signal in the distal right transverse and sigmoid sinuses, narrowing/occlusion of the proximal right transverse sinus, and prominent posterior fossa small collateral venous structures. The constellation of findings is suggestive of dural arteriovenous fistula.

(dAVF, corpus callosum signal after shunt)