Won Kyun Chung

Intraperitoneal Fluid Collection: CT Characteristics in Dertermining the Causes

Purpose: Abdominal CT scans in patients with intraperitoneal fluid were retrospectively studied to identify characteristic features useful for differential diagnosis of various causes. Materials and Methods: One hundred and seventy patients with intraperitoneal fluid collection were classified as categories of hepatic disease, carcinomatosis, and infectious disease. We analyzed sites of fluid collection , the presence of peritoneal thickening , omental and mesenteric fat infiltration, and Iymph node enlargment. Results: Intraperitoneal fluid was present in subhepatic space, subphrenic space, paracolic gutter, mesentery, and fossa ofthe gallbladder in decreasing order of frequency. Fluid in the gallbladder fossa was the most frequent in hepatic diseases. The fluid collection in subhepatic and subphrenic space was less fre quent in infectious diseases . Peritoneal thickening was noted in infectious diseases, and carcinomatosis . Omental fat infiltration and enlarged Iymph nodes were the most frequent in carcinomatosis (58% and 44% , respectively), whereas, mesenteric fat infiltration and enlarged Iymph nodes were the most common in infectiousdiseases (61% , and 26% , respectively). Conclusion: The location of peritoneal fluid collection showed some lesion specific characteristics, and CT features of fat infiltration and enlarged Iymph nodes of peritoneum, omentum, and mesenterywere helpful for differential diagnosis between carcinomatosis and infectious diseases.