Case 5 - This is a nice case of an intraperitoneal focal fat infarction.  I didn't show you the appendix in the selected images, but it was normal.  When I initially dictated this case, I think I called it an epiploic appendagitis, but now, I think is more likely to be a small omental infarction. These are often mimics of an acute appendicitis. Classically, a primary omental infarction occurs in the right lower quadrant as the blood supply to the right side of the greater omentum is not very robust. Secondary omental infarctions will most often occur in a post-surgical abdomen. Rarely, they can occur in trauma.

On CT, you want to look for encapsulated fat with surrounding inflammatory stranding. If it is in the right lower quadrant, you want to think of an omental infarction. On the other hand, epiploic appendagitis is generally left sided, most commonly in the region of the rectosigmoid colon.  However, the second most common location is in the region of the cecum. So, in order to differentiate the two, an omental infarction is larger, often over 5 cm. Regardless, it probably doesn't matter clinically as they are both treated conservatively with NSAIDS.