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Hey, Dr. P here.

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61-year-old diabetic female who presents

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with an ulcer on the plantar aspect of her

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foot, and they want to know whether there's

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osteomyelitis, which MR is just fabulous

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at excluding, you know, no more gallium

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scanning, no more bone scintigraphy, which

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can take, you know, two, three, four hours.

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MR does the job.

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And you rarely need to give contrast.

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They gave it here, Lord knows why,

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but it didn't really add anything.

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Here's the sagittal water-weighted image.

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In the center is the fat-weighted image.

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And on the far right is the

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contrast-enhanced image.

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Now, generally, when I look at the

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Charcot feet, here's my approach.

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First, one of the things you see in

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Charcot foot that's not so much present here

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is you have this very, almost painted on, ill-

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defined, low signal intensity area of sclerosis.

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Now, this is not a very sclerotic Charcot foot,

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maybe it hasn't just reached that point yet.

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The other thing you'll see is these

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erosions are very distorted and weird, multi-

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directional, but etched and sharply defined.

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Even though they're fragmented,

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they're still sharply defined.

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In this particular case, what makes the

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case easy is you look on this very, very,

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very, elegantly acquired water-weighted

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image, and you're looking for marrow edema.

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There's a little bit of marrow edema back

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here, but that's not enough marrow edema

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to be seen in an infected segment of bone.

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It's just not intense enough.

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And then I go over to my T1-weighted images

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and I actually don't see bone destruction.

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I don't see the bone wiped away, the so-

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called bone erasure sign of osteomyelitis.

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Furthermore, when I look at my plantar

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abscess and my plantar ulcer, I don't see

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a sinus tract going into the Charcot area

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of interest where osteomyelitis might live.

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And that is a very helpful sign,

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especially off the sagittal.

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You know, you trace and follow this collection.

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So, this is a case about foot masses.

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It is a foot mass.

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Here's the mass.

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And when we enhance it, most of the

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mass enhances, except for the center,

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and that center is where all the pus

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and neutrophils are going to live.

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Let's look at the short axis projection,

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and we get much of the same effect here.

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On the water-weighted image, it's

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hard to tell that we have a cavity.

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On the T1-weighted image, it's hard to

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tell that we have a cavity, but it's

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certainly easy to tell that we have no

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areas of infiltration, destruction, or wipe-

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out of the marrow signal intensity here.

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Now, sometimes, you'll have a little bit

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of cortical signal, and then you'll get

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a little bit of reactive edema over here.

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But you won't see anything

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on the T1-weighted image.

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We call that cortical osteitis, or non-invasive,

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non-penetrating cortical osteomyelitis.

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That didn't occur in this particular case, but

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with true osteo, medullary bone signal abnormal-

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here, medullary bone signal abnormal here.

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And then we injected this case again.

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We didn't have to.

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Here's the, here's all the pus and gore in

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the center of this phlegmonous collection.

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And finally, let's show you the three long axis

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projections, which once again depict from a 10,

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000-foot view, the degree of Charcot disease.

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I think you could see there's also some widening

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between the base of M1 and the base of M2.

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So the Lisfranc ligament is toast.

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It's completely gone.

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There's collapse of the midfoot.

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I'm rather surprised.

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There isn't a bit more

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sclerosis to show you, and then we've already

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made our point that this patient has a nasty

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collection in the middle here consisting

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of abscess secondary to diabetes mellitus.

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So the final diagnosis is Charcot foot

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with a plantar abscess as our mass.

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Let's move on, shall we?

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Dr. P out.