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These are images of a 45 year old male

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who had a seizure and difficulty speaking,

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and was referred to us with an acute stroke.

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And this is a non-contrast CT.

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I'm looking through it

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and I noticed what looks like a hyperdense vessel sign.

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And I noticed what looks like an MCA stroke.

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So, kind of looks like there's Subacute MCA stroke,

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a little swelling hyperdense vessel sign,

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but let's look at this more carefully.

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Number one,

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strokes in adults do not usually present with seizures.

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They can in neonates.

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They can present with seizures because neonates don't

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have inhibitory responses, but they don't present that

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way in adults, typically, in the acute setting.

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Then, two.

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Let's talk about vascular territory.

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So, this looks like MCA up here.

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It's insular, sub-insular region,

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getting into the frontal and temporal lobes,

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but down here, it looks like it's involving the medial temporal lobe,

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which really shouldn't be.

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MCA territory to be anteroinferior choroidal territory,

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and then PCA territory.

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And then, what about this hyperdense vessel sign,

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like it's not really more dense than the MCA on the right,

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it's just that it's kind of a mock effect

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because you're adjacent to hypodense tissue.

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So, I'm thinking there's something really funny about this.

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And then, like, if it's really an MCA,

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why would he present in the subacute phase

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when there's already swelling?

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Why wouldn't he have presented earlier,

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you know, you would have had a pretty bad aphasia.

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So, just between the imaging findings

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and the clinical history, I'm kind of suspicious

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that something else is going on.

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So, let's take a look at the DWI images

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and you can see that there's

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not restricted diffusion.

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It should be bright on DWI.

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That whole area is not bright at all.

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We'll look at the ADC Maps.

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Now, an acute stroke should be

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dark on ADC and this is bright on ADC,

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so there's facilitated diffusion.

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So, I'm really thinking this is

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probably an infiltrating tumor.

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and then we can look at post contrast T1 weighted images

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and you can see it's not enhancing.

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So, I'm kind of thinking it's grade 2,

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possibly a grade 3,

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sometimes grade threes don't enhance that much.

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But it really looks like tumor.

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We can also look at the T2 weighted images,

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same thing, expansile and flow voids,

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by the way, widely patent.

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There was not a CTA on that case

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but the flow voids is normal.

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Show you the coronal flair image here, too.

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Again, involvement of the mesial temporal lobe,

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not really MCA territory.

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and this turned out to be a grade 2 astrocytoma.

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So remember,

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you always have to keep your antennas up

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when you're trying to decide whether something's

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a stroke or not.

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The clinical history and the imaging findings,

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if you're good detective,

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didn't really make sense on the non-contrast CT

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and then it's obvious once you get the MR.