Internal hernia

Internal hernia is defined as "intestine enters into the large fossa, cystic space, or defect and causes closed-loop bowel obstruction." Internal hernias are classified into two types: Peritoneal fossa and peritoneal defect. The former includes paraduodenal hernia, paracecal hernia, sigmoid fossa, and foramen of Winslow, and the latter includes defects of mesentery, omentum, and uterus band. Internal hernia appears with symptoms of bowel obstruction such as abdominal pain, bilious vomiting, and abdominal distension. This condition can rapidly progress to bowel ischemia. Preoperative definitive diagnosis is difficult. Currently, due to the progress of imaging, such as color Doppler ultrasonography and CT scan, some cases can be diagnosed preoperatively. Emergent operation is recommended in cases of strangulation.