Lesser sac hernias are a type of internal hernia, where abdominal contents protrude through the foramen of Winslow, hence they are also known as foramen of Winslow hernia.
Lesser sac hernias are rare, accounting for <0.1% of abdominal hernias and 8% of internal hernias 1, 2.
- common intestinal mesentery
- intra-peritoneal right colon
- long small bowel mesentery
- large foramen of Winslow
- elongated right liver (e.g. Riedel lobe)
- gas-filled loops of small bowel in the upper abdomen
- mesenteric fat/vessels posterior to portal vein, common bile duct, hepatic artery and anterior to the inferior vena cava
- mesenteric vessels passing into the lesser sac via the foramen of Winslow
- gas and/or fluid in the lesser sac with bird beak sign towards the foramen of Winslow
- abnormal caecal position
- left paraduodenal hernia
- 1. Forbes SS, Stephen WJ. Herniation through the foramen of Winslow: radiographic and intraoperative findings. Can J Surg. 2006;49 (5): 362-3. Free text at pubmed - Pubmed citation
- 2. Martin LC, Merkle EM, Thompson WM. Review of internal hernias: radiographic and clinical findings. AJR Am J Roentgenol. 2006;186 (3): 703-17. doi:10.2214/AJR.05.0644 - Pubmed citation
- 3. Fitzgibbons RJ, Greenburg AG. Nyhus and Condon? Hernia. Lippincott Williams & Wilkins. ISBN:0781719623. Read it at Google Books - Find it at Amazon