Inflammatory fatty masses of the abdomen

Epiploic appendagitis of the vermiform appendix--An unusual mimic of acute appendicitis

Epiploic appendagitis is a condition resulting from ischemia or necrosis involving the appendage epiploica either due to torsion or spontaneous thrombosis of the venous outflow. It is one of the myriad causes of acute abdominal pain and can masquerade clinically as appendicitis, omental infarction, sclerosing mesenteritis and even diverticulitis. Epiploic appendagitis of the vermiform appendix is a rare entity, clinically indistinguishable from appendicitis. We present a 45-year-old male patient with 4-day duration of right iliac fossa pain and tenderness, with strong clinical suspicion of acute appendicitis. CT scan of the abdomen and pelvis demonstrated Epiploic appendagitis of the vermiform appendix, whilst the appendix remained uninflamed. The patient was thus discharged with conservative management without having to go undergo needless surgery, thereby avoiding the potential complications thereof.

Omental Torsion and Infarction Secondary to Omental Hernia in the Right Inguinal Canal

Omental torsion secondary to inguinal hernia has rarely been reported as a cause of acute abdominal pain. However, in our case, omental infarction due to prolonged inguinal hernia-associated omental torsion led to the formation of a large omental mass with marginal fibrosis, and the patient presented with chronic abdominal pain. A 74-year-old man presented with complaints of lower abdominal pain for 1 month; subsequently, bilateral inguinal hernias were identified through inguinal ultrasonography. CT scans revealed that the greater omentum was trapped within the right inguinal canal, leading to omental torsion. The greater omentum, distal to the pedicle, appeared as a 30 cm-sized oblong fibrofatty mass in the right lower abdomen and pelvic cavity. Laparoscopic omentectomy with hernia repair was successfully performed.

CT imaging findings of epiploic appendagitis: an unusual cause of abdominal pain

Epiploic appendagitis is a rare cause of acute abdominal pain, determined by a benign self-limiting inflammation of the epiploic appendages. It may manifest with heterogeneous clinical presentations, mimicking other more severe entities responsible of acute abdominal pain, such as acute diverticulitis or appendicitis. Given its importance as clinical mimicker, imaging plays a crucial role to avoid inaccurate diagnosis that may lead to unnecessary hospitalization, antibiotic therapy, and surgery. CT represents the gold standard technique for the evaluation of patients with indeterminate acute abdominal pain. Imaging findings include the presence of an oval lesion with fat-attenuation surrounded by a thin hyperdense rim on CT (“hyperattenuating ring sign”) abutting anteriorly the large bowel, usually associated with inflammation of the adjacent mesentery. A central high-attenuation focus within the fatty lesion (“central dot sign”) can sometimes be observed and is indicative of a central thrombosed vein within the inflamed epiploic appendage. Rarely, epiploic appendagitis may be located within a hernia sac or attached to the vermiform appendix. Chronically infarcted epiploic appendage may detach, appearing as an intraperitoneal loose calcified body in the abdominal cavity. In this review, we aim to provide an overview of the clinical presentation and key imaging features that may help the radiologist to make an accurate diagnosis and guide the clinical management of those patients.

Epiploic appendagitis: is there need for surgery to confirm diagnosis in spite of clinical and radiological findings?

BACKGROUND

The present retrospective study was conducted to review the authors' experience and describe clinical and radiologic features of epiploic appendagitis (EA), which is an uncommon, self-limiting clinical entity mimicking acute appendicitis and diverticulitis. Awareness of the features of EA would allow a correct diagnosis and avoid unnecessary surgical interventions.

METHODS

Patients diagnosed as EA in one regional medical center between June 2006 and June 2010 were included. Clinical, laboratory, and imaging features of EA were studied, with particular attention to its unique radiologic appearances.

RESULTS

Twenty patients (13 men and 7 women; average age 43.2 years) diagnosed with EA were included in the study. Localized abdominal pain without nausea, vomiting, and fever were the major presenting symptoms for all patients. Laboratory blood tests were normal, except in one patient with leukocytosis and two patients with increased serum C-reactive protein (CRP) levels. A noncompressible hyperechoic ovoid mass with hypoechoic border and without central blood flow on Doppler ultrasound (US) was detected in five of six patients. In all patients, the computed tomography (CT) scans revealed an ovoid fatty mass with hyperattenuating rim and disproportionate adjacent fat stranding. Central dot sign, concomitant old infarct, and lobulation were present in 75%, 20%, and 10% of the patients, respectively. All of the patients were treated conservatively. No recurrences occurred during the follow-up period (average: 24.8 months) in 18 (90%) of the patients.

CONCLUSIONS

In patients with localized abdominal pain without other symptoms, diagnosis of EA should be considered. Recognizing the US and CT features of EA may allow an accurate diagnosis and avoid unnecessary surgery.

Imaging manifestations of abdominal fat necrosis and its mimics

Intraabdominal fat is a metabolically active tissue that may undergo necrosis through a number of mechanisms. Fat necrosis is a common finding at abdominal cross-sectional imaging, and it may cause abdominal pain, mimic findings of acute abdomen, or be asymptomatic and accompany other pathophysiologic processes. Common processes that are present in fat necrosis include torsion of an epiploic appendage, infarction of the greater omentum, and fat necrosis related to trauma or pancreatitis. In addition, other pathologic processes that involve fat may be visualized at computed tomography, including focal lipohypertrophy, pathologic fat paucity (lipodystrophies), and malignancies such as liposarcoma, which may mimic benign causes of fat stranding. Because fat necrosis and malignant processes such as liposarcoma and peritoneal carcinomatosis may mimic one another, knowledge of a patient's clinical history and prior imaging studies is essential for accurate diagnosis.

Infarction of an epiploic appendage in a pediatric patient

Epiploic appendagitis or infarction of an epiploic appendage is an uncommon cause of abdominal pain in pediatric patients. Few cases have been reported. Diagnosis based on clinical examination alone is nearly impossible, and therefore, adjunctive radiographic measures are necessary to aid in the diagnosis, including ultrasound and computed tomography. We present the case of an 8-year-old boy whose diagnosis of epiploic infarction was suggested by computed tomography and was confirmed and treated via laparoscopy.