Primary torsion of the greater omentum with no underlying pathology was first described by Eitel in 1898 [1], and segmentary infarct of the greater omentum was described for the first time by Bush in 1896 [5]. Less than 350 cases have been reported since the description by Bush, of which only 26 were treated using laparoscopic omentectomy. Torsion of the greater omentum accounts for only 1.1% of all cases of acute abdominal pain in adults and children [6, 7]. Omental torsion is primarily seen in the 30–50-year age group, with male predominance [8]. However, a few cases have been reported in children, and the estimated incidence of torsion of the greater omentum in children undergoing surgery for presumed appendicitis ranges between 0.024 and 0.1% [9, 10]. Torsion of the greater omentum is classified as primary or secondary, the latter being far more common [11]. Secondary torsion of the greater omentum is associated with a causative condition, such as adhesions, cysts, inguinal hernia, inflammation, previous laparotomy, trauma, or tumor [12, 13].
Secondary torsion is usually bipolar because torsion of the central portion occurs between two fixed points, resulting in formation of a narrow neck or pedicle somewhere in the continuity [14]. The etiology of primary torsion of the greater omentum is unclear, though a variety of factors have been proposed. Some anatomical malformations and anomalies are recognized as predisposing factors to torsion: presence in the greater omentum of tongue-like projections and bifid and accessory omentum, anomalous vascular blood supply, other vascular anomalies that modify the weight of the omentum, vascular kinking, or irregular omental pad, seen mostly in obese patients [2, 15, 16]. Obesity is a common risk factor leading to primary torsion, with one study documenting that almost 70% of patients with omental infarction were obese [17]. Precipitating factors include sudden movements, violent exercise, hyperperistalsis, trauma, and acute changes in body position [2]. In our case, although we cannot deny the possibility that the torsion was secondary to the adhesions observed at the transverse colon and the right side of the abdominal wall, we believe that these adhesions were mainly physiological because they were relatively easily released by exfoliation. Therefore, these adhesions were unlikely to be associated with the torsion of the omentum.
Patients present with acute onset of severe abdominal pain and tenderness that is localized to the right side of the abdomen in 80% of cases [18, 19]. Gastrointestinal symptoms, such as nausea, anorexia, and vomiting, are uncommon. Torsion of the greater omentum is very difficult to correctly diagnose preoperatively and clinically because it mimics other acute pathologies including acute appendicitis, acute cholecystitis, diverticulitis, perforated duodenal ulcer, abdominal wall hematoma, intestinal obstruction, and gynecologic diseases, as documented in nearly all cases reported in surgical literature [2]. An accurate preoperative diagnosis is reported in only 0.6–4.8% of cases [20]. When compared with appendicitis, this pathology has an incidence rate of 0.0016–0.37%, a ratio of less than 4 cases per 1000 cases of acute appendicitis [11, 21].
Therefore, the diagnosis of torsion of the greater omentum is usually made intraoperatively: however, the preoperative diagnosis may be accurately determined with the use of CT [3]. Reported CT scan findings in torsion of the greater omentum include a well-circumscribed, oval, or cake-like fatty mass with heterogeneous attenuation containing strands of soft tissue attenuation probably corresponding to fibrous bands or dilated thrombosed veins [17, 22]. Ultrasound analysis is also very sensitive for the preoperative diagnosis of torsion of the greater omentum in the absence of other abdominal signs. However, laboratory findings are not specific and, apart from slight leukocytosis, mimic other pathological abdominal conditions. Reliance on laboratory findings will likely delay diagnosis and contribute to an increasing degree and duration of the torsion of the greater omentum.
The treatment of patients with primary torsion of the greater omentum is controversial. Some reports have demonstrated that most patients successfully recover with conservative treatment because primary torsion of the greater omentum is a benign and self-limiting disease. Moreover, retraction, fibrosis, and complete resolution of the inflammatory process usually occur within 2 weeks [23]. However, surgical treatment is chosen when diagnosis is uncertain, or when the patient’s clinical, laboratory, and radiological findings worsen with conservative treatment including oral analgesics, anti-inflammatory drugs, and prophylactic antibiotic. In terms of diagnostic and definitive therapy, laparoscopy is the appropriate method [24, 25].
Furthermore, the advantages of laparoscopic techniques include the following: (1) complete examination of the abdominal cavity to confirm diagnosis, (2) facilitation of aspiration and washing of the peritoneum, and (3) minimization of surgical invasiveness, postoperative pain, and wound-related complications [26,27,28,29]. In our case, we chose surgical treatment because the conservative treatment was not effective; however, the surgery was made more difficult due to chronic and persistent inflammation, which may have worsened during conservative therapy.
