Clinical Importance
Both epiploic appendagitis and omental infarct are self-limiting conditions treated conservatively (NSAIDs, analgesia). Both clinically mimic appendicitis or diverticulitis. CT is diagnostic and avoids unnecessary surgery and antibiotics. Report confidently when findings are characteristic to prevent unnecessary admission or intervention.
CT Differentiation
| Feature | Epiploic Appendagitis | Omental Infarct |
|---|---|---|
| Location | Immediately adjacent to colon wall (sigmoid most common, then cecum/ascending); antimesenteric border | Larger area of right-sided omentum most common (right lower quadrant > right upper quadrant); not directly attached to colon |
| Size | Small, ovoid; typically 1.5–3.5 cm; proportional to appendage size | Larger; typically >3–5 cm; cake-like fatty mass; may be very large (>10 cm) |
| Central hyperdense dot | Central hyperdense focus (thrombosed central vessel) within fatty lesion — characteristic sign (~70%) | Absent (no central vessel); heterogeneous fatty stranding without central dot |
| Fat stranding pattern | Oval pericolonic fat with thin hyperattenuating rim (inflamed/thrombosed epiploic appendage); surrounding inflammation limited | Diffuse, cake-like omental fat stranding; less well-defined; no discrete rim; larger area of involvement |
| Self-limiting | Yes — resolves in 2–4 weeks; rarely recurs; conservative management | Yes — resolves in 4–6 weeks; conservative management; rarely requires surgery for refractory cases |
References
Singh AK et al. Omental infarct and epiploic appendagitis: imaging characteristics and treatment. Emerg Radiol. 2005;11(2):82–7.
Radiopaedia — Epiploic appendagitis
Radiopaedia — Omental infarction