ABSTRACT
Objective To investigate the CT manifestations of gastric carcinoma invasion to lesser omentum and to assess the im-pact of lesser omentum on the spreading of gastric carcinoma.Methods We retrospectively reviewed CT findings in 48 patients with gastric carcinoma and lesser omentum involved for primary tumor and the lesser omentum abnormalities.The influence of lesser o-mentum on the extension of gastric carcinoma as well as the accompanied ascites were also analyzed.Results CT manifestations of lesser omentum involvement in gastric carcinoma included the following items:① direct infiltration (35.4%,1 7/48),which was mainly shown as increased density of fatty tissue and the development of mass within the lesser omentum,including spreading into the liver through the lesser omentum directly in two cases;② omental seeding (25.0%,12/48),including smudged appearance (1 1 cases)and omental caking (1 case);③ metastasis of lymph nodes (64.6%,31/48),including enlargement and increase of lymph nodes (27 cases)and cystic mass (4 cases).Ascites was found in 1 1 patients and fluid collection in the lesser sac was shown in 3 of these 1 1 patients.The lesser omentum forms the anterior wall of the lesser sac and separates the fluid collection in the lesser sac from the ascites in the greater peritoneal cavity.Ascites was associated with the omental seeding statistically.Conclusion CT scan is helpful for detecting lesser omentum invasion by gastric carcinoma.The imaging features consist of mass sign,enlargement of lymph nodes,smudged andcakingappearance,and so on.Lesser omentum may also play a certain role in both the extension of gastric carcinoma and the compartmentalization of ascites due to gastric carcinoma.