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The following case vignette will showcase

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two different patients, both of whom have

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morphologic imaging features of cirrhosis.

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So here we have two different

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patients, both with cirrhosis.

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These are T2-weighted sequences.

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And remember, cirrhosis represents end-stage

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liver disease, and it's really characterized

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by injury to the liver parenchyma with varying

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amounts of fibrosis and regenerative nodules.

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You know, there's lots of different

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causes of cirrhosis, including Hepatitis

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B, C, alcohol can do it, nonalcoholic

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steatohepatitis, also known as NASH, certain

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medications, certain hemochromatosis, etc.

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And some of the morphologic imaging features

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that you can see include surface nodularity.

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So if we look at these two different patients,

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and we sort of trace the outer border, we

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notice that it's a little bit more lumpy,

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bumpy, a little bit more nodular than the

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case of our patient who had a normal liver.

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Now there's varying degrees of nodularity.

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You can see in this patient

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over here, it looks like this.

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Here there's a little bit

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more pronounced nodularity.

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And it's important to also know that this

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nodularity may not always be apparent.

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So there's other imaging things

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that you need to look for.

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In order to, um, assess whether

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the patient has cirrhosis.

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If we look at the internal architecture

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of the livers in these patients who

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have cirrhosis, they're not quite as

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homogeneous as the internal architecture

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of the patient who had no liver disease.

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We can see that both on the T2-weighted

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image over here and the T1 fat-saturated

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image over here, it looks very heterogeneous,

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and there's, in general, varying

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amounts of hepatic steatosis, cirrhosis,

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reticulations, all these regenerating nodules.

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And some of these regenerating nodules can

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be difficult to sort of distinctly detect.

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These nodules are also known as regenerating

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nodules or cirrhotic nodules, and they can

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have an imaging appearance that's similar

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to liver parenchyma with enhancement.

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That's also similar, but they just

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look a little bit more mass-like.

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Sometimes if these regenerating

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nodules have iron, they can be hypo-

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intense on the T2-weighted sequences.

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If we look at this T1-weighted, fat-saturated

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image with contrast, done at a later phase,

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I believe this is an equilibrium or delayed

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phase, we can see some of that reticulation

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becoming more apparent as these sort of

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enhancing septa that sort of permeate

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throughout portions of this liver parenchyma.

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So in addition to liver nodularity,

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heterogeneity, presence of regenerating

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nodules, one of the other features that

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can be seen in patients who have cirrhosis

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is atrophy of certain segments of

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the liver and hypertrophy of others.

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One of the segments that often gets atrophied

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are, uh, portions of the right hepatic lobe.

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So if we look at this image, this is a

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T1-weighted, fat-saturated image with

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contrast in sort of a delayed, uh,

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portal venous to equilibrium phase.

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We can see the right hepatic vein over

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here joining the IVC and segments 6

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and 7 will be seen posterior to this.

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Segment 6 and 7 will be below

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the level of the portal vein.

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Segment 7 will be above it.

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And, uh, these segments, segment

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6 and 7, undergo atrophy.

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And, in addition, the medial left

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hepatic lobe also undergoes atrophy.

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So the medial segment is actually segment

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4A and 4B, will also undergo atrophy.

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We can see a portion of it right over here.

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So some segments undergo atrophy, and

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other segments, we'll undergo hypertrophy.

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One of the segments that undergoes

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hypertrophy are segments two and three,

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which is the lateral left hepatic lobe.

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So these segments over here

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are going to get bigger.

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And as a result of sort of the medial left

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hepatic lobe getting smaller and the lateral

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left hepatic lobe getting bigger, you get a

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widening often of this intersegmental fissure.

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So that's another feature to look

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for in patients who have cirrhosis.

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Another segment that can undergo

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hypertrophy is the caudate lobe.

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So we can see the caudate lobe over here.

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Really, really large.

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And oftentimes when we look at

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caudate lobe hypertrophy, it's a

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very subjective interpretation.

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But there are metrics out there to sort of

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quantify this a little bit more, and they

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include measurement of the caudate lobe

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ratio to the right hepatic lobe ratio at

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the level of the portal vein bifurcation,

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so the caudate lobe to right hepatic

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lobe, and in general, when this is above 0.6,

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it's indicative of caudate lobe hypertrophy.

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And the reasons you get sort of these

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alterations in the segmental

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anatomy, with some segments getting

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smaller and some segments becoming bigger,

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it's thought to occur because of variations

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in portal venous flow, as the portal veins get

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compressed by the fibrosis and regenerating

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nodules that are characteristic of cirrhosis.