Acoustic radiation force impulse of the liver

Acoustic radiation force impulse(ARFI)imaging is a new and promising ultrasound-based diagnostic technique that,evaluating the wave propagation speed,allows the assessment of the tissue stiffness.ARFI is implemented in the ultrasound scanner.By short-duration acoustic radiation forces(less than 1 ms),localized displacements are generated in a selected region of interest not requiring any external compression so reducing the operator dependency.The generated wave scan provides qualitative or quantitative(wave velocity values)responses.Several non-invasive methods for assessing the staging of fibrosis are used,in order to avoid liver biopsy.Liver function tests and transient elastography are non-invasive,sensitive and accurate tools for the assessment of liver fibrosis and for the discrimination between cirrhotic and non-cirrhotic liver.Many published studies analyse ARFI performance and feasibility in studying diffuse liver diseases and compare them to other diagnostic imaging modalities such as conventional ultrasonography and transient elastography.Solid focal liver lesions,both benign and malignant,are common findings during abdominal examinations.The accurate characterization and differential diagnosis are important aims of all the imaging modalities available today.Only few papers describe the application of ARFI technology in the study of solid focal liver lesions,with different results.In the present study,the existing literature,to the best of our knowledge,about ARFI application on diffuse and focal liver pathology has been evaluated and results and statistical analyses have been compared,bringing to the conclusion that ARFI can be used in the study of the liver with similar accuracy as transient elastography in diagnosing significant fibrosis or cirrhosis and has got some advantages in respect to transient elastography since it does not require separate equipment,better displays anatomical structures and measurements can be successfully carried out almost in every patient.

Radiofrequency ablation of locally advanced pancreatic adenocarcinoma:An overview

Radiofrequency ablation(RFA)of pancreatic neoplasms is restricted to locally advanced,non-resectable but nonmetastatic tumors.RFA of pancreatic tumors is nowadays an ultrasound-guided procedure performed during laparotomy in open surgery.Intraoperative ultrasound covers the mandatory role of staging,evaluation of feasibility,guidance and monitoring of the procedure.Different types of needle can be used.The first aim in the evaluation of RFA as a treatment for locally advanced pancreatic ductal adenocarcinoma,in order of evaluation but not of importance,is to determine the feasibility of the procedure.The second aim is to establish the effect of RFA on tumoral mass in terms of necrosis andcytoreduction.The most important aim,third in order of evaluation,is the potential improvement of quality of life and survival rate.Nowadays,only a few studies assess the feasibility of the procedure.The present paper is an overview of RFA for pancreatic adenocarcinoma.

Contrast-enhanced ultrasound of the pancreas

The introduction of contrast-enhanced ultrasonography(CEUS) has led to major improvements in the diagnostic capabilities of ultrasound(US).The innovative use of CEUS for study of the pancreas has created the need for a definition of the most frequent dynamic features of solid and cystic masses.CEUS is less expensive compared to computed tomography and magnetic resonance imaging and is able to significantly improve the accuracy of US,allowing better characterization and staging of pancreatic pathologies.