A ccidental foreign body ingestion is commonly encountered in clinical practice. However, bowel perforation by a foreign body is less common, as the majority of foreign bodies uneventfully pass to the feces and only 1% of them (the sharper and more elongated objects) will perforate the gastrointestinal tract, usually at the level of the ileum (1). Computed tomography (CT), especially multidetector CT (MDCT), is considered the method of choice for preoperative diagnoses of ingested foreign bodies and their complications due to its high-quality multiplanar capabilities and high resolution (2-6). The increased availability and effectiveness of MDCT has limited the use of ultrasonography (US) in investigations of acute abdominal pain (2). As a result, only a few older reports (using outdated equipment) have investigated the use of US in the diagnosis of ingested foreign bodies (7-10).Herein, we report a case of small bowel perforation and omental granuloma caused by a clinically unsuspected fish bone in which US led to a precise preoperative diagnosis and successful surgical treatment. In the era of MDCT, we highlight the usefulness of current-generation US as a radiation-free investigative tool in cases of acute abdominal pain caused by ingested foreign bodies. Case reportA 78-year-old overweight woman presented to the emergency department of our hospital with a three-day history of increasing periumbilical abdominal pain and persistent vomiting. Upon clinical examination, there was tenderness with guarding of the right upper abdomen and an elevated temperature (38.5 °C). Laboratory tests revealed increased inflammatory markers including a white blood cell count of 18.7x10 3 /μL (85% neutrophils) and a C-reactive protein level of 180 mg/L. The remaining blood test parameters were unremarkable.An abdominal X-ray in the supine position showed the presence of a distended small bowel loop at the middle abdomen but no signs of free abdominal gas or other remarkable findings (Fig. 1). The patient was referred for an abdominal US, which revealed the presence of a markedly hypoechoic mass with minimal vascularity. The mass measured approximately 4.5 cm in diameter at the right periumbilical area and contained a thin, straight, hyperechoic structure measuring 3.3 cm in length that was associated with slight posterior shadowing depending on the probe position. The fat surrounding the lesion was intensely hyperechoic, and there was an aperistaltic hypoechoic sentinel small bowel loop adjacent to the mass and connected to it by way of a linear hypoechoic sinus tract (Fig. 2). These findings raised suspicion that a foreign body was present, as this could cause both a small bowel perforation and a reactive mass.Because the patient was rapidly deteriorating, a CT scan was not performed, and the clinical decision was made to perform an urgent surgical ABSTRACT We report the case of a 78-year-old woman with a three-day history of abdominal pain and vomiting. An abdominal plain film showed a distended small bowel loop and no signs ...