The ulcer is dorsal to the head of the proximal and base of the distal
phalanx, seems to expose bone.
T1 bright marrow signal is largely preserved, bu there is marked STIR
signal hyperintensity of the proximal phalanx only.
I’m thinking back to the Case Presentations last Friday (Dr. Todeschi, are
you there?) and I don’t know how to report this.
If bone is exposed, is it osteomyelitis regardless of marrow signal? I
think that’s what I was told.
Or do I report OM of the proximal and not distal hallux?
Or does the preserved fatty marrow signal argue against osteomyelitis?
(apologies for the very ugly open 1.2T MR images)
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[image: 2.jpg]
As per Karina Todeschini:
Diabetic patient, so poor vascularity to replace marrow T1 signal. Deep
ulcer reaching the bone. Here, what really matters is the STIR signal,
which is bright in proximal phalanx. I would report as OM of the proximal
phalanx.
She added that a ratio of signal intensity (on STIR or T2) of marrow signal
vs fluid signal >53% increases specificity for osteomyelitis.
***It’s not posted yet, but when it is, you should watch last week’s Case
Presentation, Focus on Infection on the website.
***
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