Neuro_MR_Brain: 40 F, right MCA syndrome.

MRI BRAIN STROKE PROTOCOL, ANGIOGRAM NECK WITH AND WITHOUT CONTRAST:

CLINICAL HISTORY: 44-year-old woman with right MCA syndrome, right common carotid abnormality noted at outside hospital.

FINDINGS:

BRAIN:

Parenchyma: Multiple acute infarcts are seen in the right cerebral hemisphere, with large territory involving the posterior right frontal lobe and medial right parietal lobe, crossing typical ACA/MCA territory, with additional foci in the right temporal occipital region, near the ACA MCA border zone, anterior putamen, right caudate head, posterior right caudate body/superior thalamus, and smaller foci in the anterior right frontal lobe. Large area atypical for multiple small emboli, however all infarcts conform to right anterior circulation. No evidence of acute hemorrhage. There is associated edema on FLAIR, with swelling of the gyri. No midline shift or herniation. There is an area of irregular cortical enhancement involving the posterior right inferior frontal gyrus (image 11:181), likely related to blood brain barrier breakdown in setting of ischemia.

Ventricles and extra-axial spaces: Appropriate for age.

Orbits: Normal.

Visualized paranasal sinuses: Clear.

Mastoid air cells: Clear.

Bones: Normal.

Additional comment: None.

INTRACRANIAL ANGIOGRAM:

Anterior circulation: No flow-limiting stenosis or large vessel cutoff seen. Slight attenuation of right M4 branches, difficult to assess given smaller caliber and given that the vessels are at the edge of the volume of the field of view. Fetal left posterior communicating artery.

Posterior circulation: No flow-limiting stenosis or aneurysm.

Dural venous sinuses: Patent.

Additional comment: None.

EXTRACRANIAL ANGIOGRAM:

Proximal great vessels: There is a crescentic narrowing of the distal right common carotid artery on time-of-flight imaging, relatively long segment, with suggestion of dissection flap on contrast MRI (images 16:40-44). Degree of narrowing approximately 50-70% at most narrow point, likely closer to 70%. Left common carotid artery is widely patent.

Cervical vessels: Internal carotid arteries and vertebral arteries are unremarkable.

Additional comment: None.

PERFUSION:

There is hypoperfusion on ASL and bolus perfusion to areas of infarct, no perfusion diffusion mismatch to suggest tissue at risk.

IMPRESSION:

1. Distal right common carotid dissection (50-70% at the most narrow point), with multiple acute to subacute infarcts in the right anterior circulation distribution. Edema associated with areas of infarct, with focal area of enhancement in the right inferior frontal gyrus also likely secondary to ischemia.

2. No intracranial large vessel cut off identified. No perfusion diffusion mismatch to suggest tissue at risk.

(Right common carotid artery dissection)