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This was a 55-year-old gentleman who was in a motor vehicle

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collision and presented, 24 hours after the relatively minor

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motor vehicle collision,

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with a nuanced set of left-sided weakness.

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Looking at the CT scan,

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which was the initial study,

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I was unimpressed with any evidence

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of intraparenchymal hemorrhage,

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extra-axial fluid collection, hydrocephalus,

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subarachnoid hemorrhage. And looking at the bone windows,

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there was no evidence of a fracture.

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This is an example of looking for something that is

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relatively unusual or uncommon in a different setting.

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If I had said that this was a patient

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who was concerned about a stroke,

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we would spend a little bit more time on the blood vessels.

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And as you scroll superiorly,

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you note that the patient has a hyperdense blood vessel

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in the Sylvian fissure on the right side.

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Going back,

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you can see that it begins at the proximal Sylvian fissure.

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And this was identified on the initial scan as representing

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a possible clot in the right middle cerebral artery.

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Now, with that history of trauma,

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one has to be concerned about the potential for a dissection

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of that blood vessel leading to a clot.

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If this was a gentleman who had a history of hypertension or

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atrial fibrillation or left ventricular mural thrombus,

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we would just assume that this was a thromboembolic clot

1:44

from either a carotid plaque or from something

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arising from the heart. In this case,

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the temporal relationship to the motor vehicle collision

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brings in the possibility of a clot

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from a dissected blood vessel.

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The patient subsequently got a CT angiogram

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to evaluate for potential dissection.

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As we proceed inferiorly from the vertebral

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arteries going superiorly,

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we see a nice definition of the basilar artery and the

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internal carotid arteries in the cavernous sinus.

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And following out to the termination of the

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internal carotid artery on the right side,

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we identify the A one segment of the anterior cerebral

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artery and the M one segment of the middle cerebral artery.

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As we follow this blood vessel out to the periphery,

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we note that at the bifurcation, things look pretty good,

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but we lose the blood vessel in the

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proximal Sylvian portion. Here,

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there's just a tiny stream of minimal contrast going around.

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This caught

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the sea.

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T scan that preceded the CTA on the same day

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makes this a little bit more clear.

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Here we have the clot in the proximal Sylvian portion of the

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middle cerebral artery just distal to the middle cerebral

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artery bifurcation, and unfortunately, as you can see,

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low-density area in the perisylvian subinsular region

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identified as an early stroke.

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So this is an example of dissection with clot

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formation after trauma. In my experience,

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the distal internal carotid artery terminus

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and the middle cerebral artery,

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generally M one or M two segments of the middle cerebral

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artery are the blood vessels that are

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at highest risk for dissection,

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and usually it's in those proximal portions to have

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a dissection involving the vertebral basilar artery.

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Circulation in the brain is entirely uncommon.

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However,

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please note that most dissections after trauma

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occur in the neck rather than intracranially.