“…However, several authors have reported cases in which abdominal sonography demonstrated indirect and direct signs indicative of PUP, though most of the indirect signs-such as subphrenic and subhepatic fluid collection, fluid accumulation in the lesser omentum, thickening of the gallbladder wall, an inflammatory mass in the upper abdomen, focal or diffuse thickening, and deformity of the wall of the gastric antrum or duodenal bulb-are not specific for PUP. [3][4][5][6] Furthermore, most of these signs can be more accurately demonstrated with CT. 3 However, CT is an expensive procedure, and it is not as widely available as sonography, thus sonography is often used as a first-line imaging modality in patients with abdominal pain. Lee et al 5 first…”