M-mode ultrasound for assessment of the “tethered fat sign” in children: an easily performed way to certify a dynamic process as a still picture

Omental infarction is a rare pediatric disease. Ultrasound is a useful modality for a non-invasive pre-operative differential diagnosis between inflammatory conditions (as appendicitis) and omental infarction, especially by detecting immobility of the omentum adhered to the abdominal wall ("tetherd fat sign"). However, this is a dynamic sign that cannot be documented in a static image with B-mode technique. The goal of this work is to incorporate the versatile function of motion mode (M-mode) into omental infarction diagnosis to describe how the M-mode is useful in the evaluation of fat motion in children suspected of having omental infarction. In 2019 we suggested a new Ultrasound sign named "tethered fat sign" for an accurate non-invasive diagnosis of omental infarction in children. This finding was observed in 6 of the 234 seen children of our previous study with 4 laparoscopic confirmed diagnosis.