Diagnostic value of multidetector computed tomography in differentiation of benign and malignant omental lesions

Abstract

Objective: To assess the diagnostic value of multidetector computed tomography (MDCT) in differentiation of benign and malignant omental lesions. Patients and methods: MDCT scan was performed for 37 patients with omental lesions after administration of oral and intravenous contrast. The CT diagnosis was compared with the final histopathological findings. Sensitivity, specificity, and diagnostic accuracy of MDCT were calculated using surgical and histopathological findings as the gold standard. Results: MDCT findings of all cases with omental torsion, cystic lymphangioma, and loculated fluid in the greater omentum correlated with the surgical and histopathological findings with 100% diagnostic accuracy. However, the diagnosis was missed in two patients from seven (2/7) with tuberculous peritonitis and in two patients from 21 (2/21) with peritoneal carcinomatosis with sensitivity, specificity and diagnostic accuracy of 73%, 92%, 85% and 90%, 95%, 93%, respectively. Conclusion: MDCT is an excellent diagnostic tool for evaluating omental lesions, especially those present with nonspecific clinical manifestations.

CT imaging features of fat stranding in cats and dogs with abdominal disorder

“…This may be due to the peritoneal defense mechanisms for wound isolation which prevents the spread of the abdominal infection by wrapping around the lesion. In addition, the omentum and mesentery act as boundaries for pathological processes for disease localization [ 22 25 26 27 ]. In patients of severe inflammatory disease such as necrotic pancreatitis, local inflammation can spread over the surrounding tissue or even progress to a systemic response and cause fat stranding in remote places apart from the lesion [ 4 5 28 ].…”

“…This CT pattern approach is a useful diagnostic tool for differentiating benign peritoneal disease from malignancy because the prevalent pattern is determined according to the malignant potential of the underlying lesion [ 21 ]. The CT appearance of fat stranding in the omentum and mesentery is dependent on the duration of the disease [ 26 ]. It presents as a smudged appearance in the early stage, and as the disease progresses, soft tissue nodules form.…”

“…However, this result did not mean that the reticulonodular pattern was a pathognomonic feature for a malignant tumor, because this pattern was also observed in severe inflammation such as severe pyogranulomatous panniculitis in a dog. Similarly, in humans, fat stranding with a reticulonodular pattern is also reported in inflammatory diseases by fatty inflammation and fibrosis such as mesenteric panniculitis or tuberculosis although less common compared to malignant tumors [ 26 31 ]. In humans, a ground-glass pattern is most often caused by mild inflammation and the reticular pattern is found with increasing severity of the inflammation [ 20 ].…”