An extremely unusual condition that leads to intestinal obstruction: Foramen Winslow hernia.

It is known that foramen Winslow hernia (FWH) is a very rare disease and difficult to diagnose because there are no specific examina-tion findings. Patients usually present to the emergency department with an intestinal obstruction. Delay in diagnosis may cause isch-emia and perforation of the intestinal loop. Difficulties in early diagnosis increase the probability of this condition resulting in mortality. A 41-year-old male patient was admitted to the emergency department with colic abdominal pain lasting for 2 days. The patient was hospitalized for further examination and treatment. Due to the improvement in his clinical state, the patient was discharged; however, 2 days later, he was readmitted to the emergency department with an inability to pass stool or flatus, nausea, and vomiting, as well as abdominal pain. After laboratory tests and imaging methods were applied to the patient, surgery was decided upon. In the laparoscopic examination, it was observed that the small bowel loop herniated into the foramen Winslow (FW) at 220 cm proximally from the ileocecal junction. Herniated bowel loops were reduced. The open FW was not intervened in, and the operation was terminated. Due to their rarity, FWHs are less likely to be considered a preliminary diagnosis in individuals who present to the emergency department with intestinal obstruction. FWH may be considered in patients with congenital anomalies and without previous abdominal surgery. The best imaging technique for diagnosis is contrast-enhanced abdominal computed tomography (CT), and it is critical to recognize bowel loops in the omentum minus on CT.