Echo-enhanced ultrasound with pulse inversion imaging: A new imaging modality for the differentiation of cystic pancreatic tumours

To describe and discuss echo-enhanced sonography in the differential diagnosis of cystic pancreatic lesions. The pulse inversion technique (with intravenous injection of 2.4 mL SonoVue) or the power-Doppler mode under the conditions of the 2nd harmonic imaging (with intravenous injection of 4 g Levovist) was used for echo-enhanced sonography. Cystadenomas frequently showed many vessels along fibrotic strands. On the other hand, cystadenocarcinomas were poorly and chaotically vascularized. "Young pseudocysts" were frequently found to have a highly vascularised wall. However, the wall of the "old pseudocysts" was poorly vascularized. Data from prospective studies demonstrated that based on these imaging criteria the sensitivities and specificities of echo-enhanced sonography in the differentiation of cystic pancreatic masses were >90%. Cystic pancreatic masses have a different vascularization pattern at echo-enhanced sonography. These characteristics are useful for their differential diagnosis, but histology is still the gold standard.