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This next patient is a 44-year-old female with an

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indeterminate liver mass in another imaging modality.

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An MRI was, uh, requested to, uh, evaluate this

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lesion, and we did this using, uh, EOVIST, Asian

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with partial hepatobiliary excretion, because

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there was some suggestion that this could reflect

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focal nodular hyperplasia or hepatic adenomas.

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So we'll start off by looking at our T2-weighted sequences.

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As we scroll through these images, when you look at it,

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there are multiple liver lesions seen in this liver.

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You can see some over here, one over here, So we'll

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start off by looking at our T2-weighted sequences.

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You scroll downwards, and you look at this.

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There's going to be multiple liver

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lesions seen in this, uh, patient.

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The one that I'll focus on for this particular vignette

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is going to be the lesion here on the right hepatic lobe.

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On the T2-weighted images performed without

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fat saturation, we can see that, uh,

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the lesion's a little bit heterogeneous.

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There is a periphery surrounding it over here, this

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sort of periphery that is slightly, uh, hyperintense

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on the T2-weighted images, centrally maybe more

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isointense with respect to the liver parenchyma.

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On the T2 Turbospin echo sequence performed with

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fat saturation, this is the sequence we're going

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to look at for the true T2 signal of this lesion.

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We can indeed see that this looks like a little bit of a

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donut with hyperintense signals seen at the periphery of

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this lesion and more isointense signal seen centrally.

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We'll come back to that hyperintense peripheral T2 signal.

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in a little bit.

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We'll move on to the T1 in and out of phase image.

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And again, we'll go to our index

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lesion, the right hepatic lobe.

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And the out-of-phase sequence over here, the in

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phase sequence over here, very, very tough to see it.

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It's probably going to be this lesion over here.

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And generally it's isointense to slightly hyper

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intense with respect to the liver parenchyma.

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Certainly has no evidence that it contains fat within it.

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There's no loss of signal within this

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lesion on the out-of-phase images.

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And nothing to suggest it has any substances

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that cause increased susceptibility artifact.

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We'll move on to our pre-contrast T1 fat-saturated sequence.

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And even on this sequence, quite difficult

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to see this lesion probably in this location.

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Probably slightly T1 hyperintense to iso

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intense with respect to the liver parenchyma.

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We have to look at the post-contrast imaging

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sequences to see how this enhances to make

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a final assessment of what we think this is.

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So here we have our post-contrast imaging sequences

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demonstrating the lesion indeed does enhance.

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On the arterial phase images, homogeneous arterial

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hyperenhancement, portal venous phase images remains

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hyperintense with respect to the liver parenchyma.

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On the equilibrium phase images, again, remains

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hyperintense with respect to the liver parenchyma.

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So here we have a lesion that had a

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periphery that was slightly T2 hyperintense.

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No lipid within it on the T1 in and out of phase images.

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Post-contrast demonstrates pretty homogeneous enhancement.

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That remains hyperintense with

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respect to the liver parenchyma.

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We finally have to see what this does on

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our 20-minute post-contrast phase to make

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an assessment of what this is going to be.

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Here we have our 20-minute post-contrast image.

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And on it we can once again see that this lesion is

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hypointense with respect to the liver parenchyma.

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So again, the imaging features here

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are compatible with hepatic adenomas.

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This patient happens to have other hepatic adenomas here.

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As a side, if you have more than 10 hepatic adenomas,

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which this patient doesn't have, but if you do have

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more than 10, it's actually known as adenomatosis,

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But one of the reasons I wanted to show this case

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was twofold, firstly to show that a lot of adenomas

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that you encounter may not necessarily contain fat.

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And secondly, there's a particular sign that we, uh, name

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for that specific T2 appearance seen in this case, which

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is that peripheral halo of, um, hyperintense T2 signal,

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and that's actually called the ATOL sign, which, uh, is

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thought to be reasonably specific for hepatic adenomas.

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Um, and it's thought to reflect dilated

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sinusoids seen at the periphery, um, of this

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lesion as it compresses the liver parenchyma.