Right MCA infarct

Case contributed by Bruno Di Muzio
Diagnosis certain


Left side hemiparesis. Code stroke.

Patient Data

Age: 45-year-old
Gender: Female

CT Brain - CTA and Perfusion



CT brain.

Ill-defined hypoattenuation within the posterosuperior aspect of the right frontal lobe involving the precentral gyrus and within the centrum semiovale most consistent with acute ischemic change. Other regions of parenchymal hypoattenuation within the right cerebral hemisphere involving the anterior limb of the right internal capsule and posterosuperior cortex of the right parietal lobe have a more chronic appearance and may represent old ischemic change.

No acute intra-axial or extra-axial hemorrhage. No intracranial mass or mass effect. Brainstem and cerebellum are unremarkable.


Acute thrombus with occlusion of the M1 segment of the right MCA. Normal contrast opacification of the ACAs, PCAs and left MCA. Normal circle of Willis anatomy. Normal contrast opacification of the common carotids, internal carotids, vertebral and basilar arteries.

Matched cerebral blood flow defect within the posterosuperior right frontal lobe and centrum semiovale suggestive of established infarct, increased T-max throughout the MCA territory consistent with surrounding penumbra. Evaluation of the deep white matter within the right cerebral hemisphere is difficult due to what appears to be regions of established chronic ischemic change on non-contrast imaging. Calculated cerebral blood volume defect measuring 22.6 ML and perfusion defect measuring 63.9 ML, calculated mismatch ratio of 2.8. The anterior MCA distribution with increased T-max is not included in the automated calculation of the perfusion defect volume.

Impression: Acute thrombus with occlusion of the M1 segment of the right MCA with a perfusion defect consistent with a large region of penumbra within the MCA territory.

On the non-contrast CT brain there is an area of ill-defined hypoattenuation in the posterosuperior right frontal lobe and centrum semiovale consistent with acute ischemia. Other regions of hypoattenuation within the right cerebral hemisphere have a more chronic appearance and may represent chronic ischemic change.

DSA - Cerebral angiography


Technique: The patient presented with decreasing conscious state / left hemiplegia. CTA confirmed occlusion of right MCA M1 segment extending into both superior and inferior division.

After discussions with the stroke team - last seen well, first observed with left hemiplegia and neglect and speech difficulty, moderate core but mismatch and large vessel occlusion, referred for consideration of endovascular clot retrieval.

Under sterile technique, the right CFA was accessed using an 8Fr sheath, and selective injections were made into the Right CCA and ICA.

Findings: Procedure performed with the patient awake - limited ability for subsequent more selective vessel access. There is a greater than 70% stenosis of the origin of the right internal carotid artery, and occlusion of the mid M1 segment, with moderate collaterals.

An 8 Fr Balloon Guide Catheter was placed in the right internal carotid artery, carefully passed the ostial atheroma, 3 passes with Solitaire 4 x 20 / 2 passes with the Trevo 6 x 40 stent retriever concomitant aspiration under balloon inflation. Subsequently, the using a 5-French Sofia catheter, and the penumbra suction equipment, direct aspiration of a resistant cough was performed with 2 separate passes.

IA Verapamil used to manage ICA vasospasm.

Despite this, there was minimal retrieval of thrombus, and only limited reperfusion with ongoing high-grade narrowing at the MCA bifurcation.

Procedure took 2 hours; 5 passes with moderate and large stent retriever; 2 passes of 5Fr aspiration distal access catheter - as time of onset unknown, edema on CT, modest infarct on CTP, no further intervention (and no stent placement).

At end of the procedure groin was closed with the 8Fr Angioseal device.

Conclusion: Unknown time of onset of right MCA syndrome, high NIHSS, ICA atheroma presumed source of M1 occlusion, but proved resistant to multiple devices and techniques for clot retrieval.

Poor - TICI 2a at most - reperfusion.

CTB after DSA


Comparison is made to the study performed earlier today.

New hyperdensity within the right corona radiata, caudate head and lentiform nucleus more likely represents contrast staining from recent angiographic procedure than acute hemorrhage. No established infarct demonstrated, however there is mild gyral swelling on the right. No midline shift. No hydrocephalus. Tiny volume of gas in the right cerebral hemisphere with serpiginous morphology, consistent with intravascular location.

CT Brain (one day later)


Comparison is made to the previous CT brain.

Geographic region of hypodensity in the right basal ganglia, insular cortex, frontal, parietal and superior temporal lobes with loss of grey-white differentiation in keeping with acute right MCA territory infarct. This produces mass-effect, with effacement of the right cerebral convexity sulci, midline shift to the left measuring 4 mm at the septum pellucidum and distortion of the right lateral ventricle. Hyperdensity in the right basal ganglia are likely reflects contrast staining from the recent angiographic procedure. No acute intracranial hemorrhage.

Impression: New acute right MCA territory infarct.

CT Brain (one day later)


Non-contrast study is compared with prior examination.

Right MCA territory infarct shows no evidence of extension or hemorrhage. Some hyperdensity is still noted within right-sided MCA branches, however less well-defined blushes of contrast are no longer evident and there is no suggestion of interval hemorrhage.

There is however increased surrounding edema and associated mass effect with greater sulcal effacement, bowing of the falx to the left and up to 7 mm of subfalcine herniation at the level of the third ventricle, previously 3-4 mm. Early right uncal herniation is also evident. The right lateral and third ventricles are partially effaced. Mild distortion of the midbrain with effacement of surrounding ambient cisterns.

CT Brain (one day later)


A right pterional craniotomy has been performed, with thin underlying extra-axial collection. There is minor brain herniation out of this defect. Right MCA territory infarct is again demonstrated with no definite extension or hemorrhagic transformation. Reduced midline shift of 3 mm to the left as measured at the septum pellucidum. Partial effacement of the right lateral and third ventricle. No hydrocephalus. No remote or acute intracranial hemorrhage or cortical infarct.

Case Discussion

This patient had an unknown time of onset of a right MCA syndrome. First CT and CTA/Perfusion had demonstrated M1 segment occlusion and established infarct on the right MCA vascular territory. DAS clot retrieval was then attempted after discussion with the stroke team, but, unfortunately, was not successful, with only a minimal reperfusion achieved. The series of sequential CT brains shows the evolution of the large territory ischemia with edema and mass effect, requesting for a decompressive craniectomy a few days later. 

Interesting to note the presence of contrast-stained within the brain parenchyma after the DSA procedure. This should be differentiated from hemorrhagic transformation. 

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