Figure 2.

2A: Longitudinal scan of the patient's right trochanter. The b-mode image shows a medium sized onchocercoma. The observer can easily differentiate between the worm centre containing a conglomerate of coiled adult filaria (e) and the capsule of the nodule. The worms are surrounded by cystic fluid. The yellow arrowheads are positioned where worm movements were detected. The conglomerate of worms causes a strong back wall reflection behind the onchocercoma. 2B: Transverse scan of the patient's right iliac crest. A large onchocercoma with a small cystic area (echo-free-black – zone) can be seen. The yellow arrowheads are positioned where worm movements were detected. Fragments of the worm body can be seen as a double layer membrane. The corresponding video image can be seen as Additional File 1.