HSS Ultrasound Case #98

Clinical History 40 year old male with recent tibiotalocalcaneal arthrodesis with failure of the arthrodesis and progressive swelling in the anterior aspect of the ankle.

The patient was referred for ultrasound-guided aspiration to rule out infection after fluid collections were seen on CT scan and MRI.

Ultrasound of the Month – Case 98

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Ultrasound of the Month – Case 98

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Ultrasound of the Month – Case 98

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Ultrasound of the Month – Case 98

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Diagnosis: Soft Tissue Abscesses of the Ankle Discussion Fluid collections in the postoperative setting may represent seromas, hematomas, or abscesses.

The imaging appearance of these different types of fluid collections can overlap, although certain features can suggest one diagnosis over another.

Ultrasound is an ideal modality for localizing fluid collections in the soft tissues.

On ultrasound, wall thickening, surrounding hyperemia, internal septations, and sinus tracts are features, if present, that suggest that a fluid collection may be an infected collection/abscess.

Sample of fluid is required for definitive diagnosis and for identifying the offending organism; one advantage of ultrasound is that it can be used to guide aspiration of the fluid collection.

Ultrasound of the Month – Case 98

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