Summary: Case 1: A 41-year-old man presented with sharp pain localized
to the left upper quadrant for 1 day. The pain was exacerbated by
movement and lifting. The patient complained of mild anorexia, but
denied nausea, vomiting, change in bowel habits, melena, or weight loss.
On physical exam he was moderately tender to palpation in the left
upper quadrant. His white blood cell count, hemoglobin, and hematocrit
were normal. The patient was discharged after being scheduled for an
outpatient computer tomography (CT) scan.
Summary: He returned 2 days
later with persistent pain. Physical exam again revealed moderate
tenderness to palpation in the left upper abdomen. The patient was given
an analgesic and a CT scan of the abdomen and pelvis was performed.
Summary: Case 2:
A 40-year-old woman presented with constant right lower quadrant
abdominal pain of 4 days’ duration. The pain was associated with nausea
and exacerbated by coughing and movement. She denied fever, vomiting, or
change in bowel habits. On physical exam she was moderately tender to
palpation in the right lower quadrant. Her WBC was 10,100. A CT scan of
the abdomen and pelvis was performed.
Primary epiploic appendagitis
Case 1: A contrast-enhanced abdominal/pelvic CT scan
demonstrates a 1.7-cm, oval-shaped fatty mass with peripheral ring
enhancement projecting anteriorly from the descending colon (Figure 1).
Surrounding inflammatory changes are present in the pericolonic fat. No
peritoneal wall thickening, bowel wall thickening, or mass effect
Case 2: A contrast-enhanced abdominal/pelvic CT
scan shows 2.7-cm × 2-cm ovoid fatty mass with a 2-mm hyperattenuating
ring and a central area of hyperattenuation projecting from the
ascending colon (Figure 2). Inflammation of the surrounding fat and
peritoneal wall thickening are present. The bowel wall is minimally
thickened. No significant mass effect is seen on the adjacent bowel.
The remainder of the scan did not demonstrate any other abnormalities.
The appendices epiploicae are lobular pedunculated subserosal fatty
masses projecting from the anterior and posterolateral walls of the
ascending and descending colon. A single row projects from the
transverse colon. They are numerous (typically 100),
2 cm to 5 cm in length, and most prominent along the descending and
sigmoid colon. Epiploicae 15 cm in length have been reported.1 Epiploic appendagitis has a predominance for the cecum and sigmoid colon.1,2
The epiploicae are susceptible to torsion and spontaneous venous
thrombosis, particularly after vigorous exertion. Presentation is
typically sudden focal abdominal pain that increases with cough and
stretching. Vomiting and changes in bowel habits typically are not
associated complaints. The patient’s temperature and WBC count may be
slightly elevated.3,4 Symptoms usually persist for 3-7 days.3
Conditions that enlarge the peritoneal cavity, such as obesity,
ascites, recent pregnancy or abdominal surgery, may make the epiploicae
more susceptible to torsion.1
epiploicae are not visualized on routine CT examinations unless there is
contrast material present, such as ascites or blood.1
Epiploic appendagitis has a characteristic CT appearance described as an
oval fatty mass measuring 1-4 cm in diameter of increased attenuation
relative to normal fat. The defining characteristics are a
hyperattenuating ring 1-3 mm thick associated with periappendageal
inflammatory changes. The hyperattenuating ring is thickened visceral
peritoneal lining. The center of the fatty mass may contain a linear or
rounded area of hyperattenuation due to thrombosed vessels, hemorrhagic
necrosis, apposition of two adjacent appendices, or septal fibrosis.
Mass effect on the adjacent bowel wall and peritoneal or bowel wall
thickening may also be present.3-5
Follow-up CT scans
demonstrate a decrease in size of the lesions with a change in shape to
irregular, oval, or rounded. Changes in the attenuation of the involved
epiploicae vary from decreasing attenuation to increasing attenuation.
Periappendageal fat stranding and adjacent bowel-wall changes typically
resolve with healing.4,5 CT findings may persist for more than 19 weeks.4
epiploic appendagitis’ clinical presentation and CT appearance are
similar to that of segmental omental infarction (SOI). Segmental omental
infarction can be differentiated from epiploic appendagitis by its
heterogeneous appearance, medial location with respect to the ascending
and descending bowel, and lack of peripheral enhancement. SOI is also
larger and causes greater mass effect on the adjacent bowel.3,6,7 Since both are treated conservatively, differentiation is of no clinical consequence.6,7
diagnosis should also include secondary epiploic appendagitis,
diverticulitis, appendicitis, and cholecystitis. Secondary epiploic
appendagitis is caused by inflammation of adjacent organs, most commonly
due to diverticulitis.1,5 Primary epiploic appendagitis can only be diagnosed when findings for diverticulitis and appendicitis are absent.6,7
Epiploic appendagitis, once thought to be a rare condition, is now more
commonly diagnosed with the routine use of CT scans in the evaluation of
abdominal pain. It has a characteristic CT appearance of an oval-shaped
fatty mass of increased attenuation surrounded by an enhancing ring and
periappendigeal fat stranding. Since epiploic appendagitis is treated
conservatively, its diagnosis can prevent unnecessary surgical
- Ghahremani G, White E, Hoff F, et al. Appendices epiploicae of the colon: Radiologic and pathologic features. Radiographics. 1992;12:59-77.
- Lynn T, Dockerty M. A clinicopathologic study of the epiploic appendages. Surg Gynecol and Obstet. 1956;103:423-433.
- Rioux M, Langis P. Primary epiploic appendagitis: Clinical, US, and CT findings in 14 cases. Radiology. 1994;191:523-526.
- Rao P, Wittenberg J, Lawrason J. Primary epiploic appendagitis: Evolutionary changes in CT appearance. Radiology. 1997;204:713-717.
- Sirvanci M, Tekelioglu M, Duran C, et al. Primary epiploic appendagitis CT manifestations. J Clin Imaging. 2000;24:357-361.
- van Breda Vriesman A, de Mol van Otterloo A, Puylaert J. Epiploic appendagitis and omental infarction. Eur J Surg. 2001;167:723-727.
- Mcclure M, Khalili K, Sarrazin J, Hanbidge A. Radiological features of epiploic appendagitis and segmental omental infarction. Clin Radiol. 2001;56:819-827.