Diagnosis of focal pancreas lesions with CEUS and EUS

Objective: CEUS (contrast enhanced ultrasound) is very limited researches on the focal pancreas lesions. The aim of this study is to characterize the enhancement patterns of focal pancreas lesions with CEUS and to compare to the accuracy of CEUS and EUS in diagnosis.

Materials and methods: Between2004 and2005, 30 cases with focal pancreatic lesions were examined by CEUS and EUS. All of the cases were confirmed by pathologic examination. We used the Acuson Sequoia 512 color Doppler ultrasound equipment with CPS contrast specific technique. The contrast agent are SonoVue. Olympus EU-M30 and 7.5–12MHZ radical scanning probe were for EUS.

Result: In CEUS 11 of 12 cases with pancreatic head carcinoma, the enhancement was later than the pancreatic parenchyma, the peak of enhancement was heterogeneous and lower or equal to the pancreatic parenchyma, the wash-out was earlier than pancreatic parenchyma,. They washed out before 60 seconds quickly and the boundaries of the tumors became cleanlier. But the wash-out time in 1 case was the same with the pancreatic parenchyma. The enhancement and wash-out of 4 cases with tumor-like pancreatitis were just the same with pancreatic parenchyma. But 2 of 3 cases of insulinoma located in pancreatic tail can't be detected by CEUS. In EUS 10 cases of pancreatic head carcinoma, 2 cases of tumor-like pancreatitis and 2 cases of pancreatic tail insulinoma were been diagnosis correctly.

Conclusion: ECUS are more sensitivity in differential diagnosis of pancreatic carcinoma and tumor-like pancreatitis by heterogeneous hypo-enhancement and early wash out in focal pancreatic head lesion. But EUS are more sensitivity in detection of small pancreatic tail lesion.