I have previously been frustrated with Hidradenitis – what seems like a abscess that is going to yield pus and is worth draining was only a mass of scar when you incise it in these unfortunate people plagued by repeated abscesses. When this patient presented with two larger, very tender but non-fluctuant masses in a field of smaller inflamed nodules in the axilla the question was – is there frank pus here to incise and drain, or can I be sure antibiotics alone with resolve this?
The linear probe was very helpful here – yes there was a true pus filled collection and the registrar and myself proceeded to drainage which produced laudable pus. A small, simple POCUS win. Next time I would use a standoff to get a bit more skin definition but this image represents a nice hypoechoic collection with ring enhancement and a ring down artifact deep to the abscess.