This is a 47-year-old gentleman with right lower quadrant abdominal pain:
The arrow points to a well-circumscribed area of fat stranding and inflammation in the right lower quadrant. This is highly suspect of an omental infarct.
I must confess, in my short tenure as an ED physician I had never come across this diagnosis. I had to look it up. Here’s a link to case report which discusses omental infarction from the International Journal of Surgery Case Reports:
Quick summary (1): As it turns out this is somewhat rare but can present much like appendicitis. It is estimated to occur 4 times per 1000 cases of appendicitis. Omental infarction is most common in the right lower quadrant and can be associated with various medical disorders such as vasculitis, hypercoagulability, polycythemia, pancreatitis, omental cysts, tumors, and adhesions. However, most of the time it is idiopathic and seems to have an association with obesity. The theory is that fatty accumulation in the omentum impedes the distal right epiploic artery or causes a torsion of the omentum. CT is the diagnostic imaging of choice but this is sometimes caught with laparoscopic exploration for presumed appendicitis. CT signs include the well-circumscribed fatty inflammation, fat stranding, and a “whirl sign.”
Another free article from the Journal of Surgery Education with a great CT image of the “whirl” sign:
The treatment of omental infarction used to be surgical exploration (2). General consensus currently suggests a course of conservative, non-surgical management with supportive care (however there is no authoritative therapeutic strategy). From reading both of these case reports it seems to reason that a trial of inpatient supportive care with laparoscopic exploration and omental resection if the patient clinically doesn’t respond. As an ED physician, I would suggest getting surgery involved and deferring to their surgical expertise with the knowledge that there is no clear answer between supportive care and immediate surgical intervention.
Author: Russell Jones, MD
1. Kushal PB, Benjamin CK. Diagnosis and management of idiopathic omental infarction: A case report. Int J Surg Case Rep. 2011; 2(6): 138-140.
2. Itenberg E, Mariadason J, Khersonsky J, Wallack M. Modern Management of Omental Torsion and Omental Infarction: A Surgeon’s Perspective. J of Surg Ed. 2010; 67(1): 44-47.