1255: 3D ultrasound and the diagnosis of gallbladder diseases

Abstract

Three-dimensional ultrasonography (3D-US) is now a widespread diagnostic technology. With the help of external workstation and magnetic positioning system (“free hand” method) 3D-US can be carried out with the use of any ultrasound diagnostic system. The dedicated systems with 3D probes (both mechanical and electronic) allow receiving either “live 3D” (up to 16 volumes/s) or “3D in real time or 4D” (16 and more volumes/s). However, despite the availability 3D-US, questions of its practical application and economical feasibility remain open. The gallbladder is an organ for which localization and structure are rather convenient for carrying out 3D-US. Presence of a liquid in a gallbladder cavity allows visualizing, differentiating and characterizing internal masses especially well. Potential directions in 3D-US application are the following: (1) gallbladder volume assessment; (2) gallbladder wall assessment; (3) gallbladder cavity masses assessment. Gallbladder volume measurement is important for assessment of its function. Accuracy of volume measurement with the help 3D-US is much higher than that of two-dimensional (2D) one. The relative error of a sum-of-cylinders method can be as high as 34%, and of an ellipsoid method can be as 72%. It is very important that reproducibility of gallbladder volume measurement with 3D-US is the highest and that it greatly surpasses 2D techniques. The gallbladder wall and surrounding tissues, structure and gallbladder wall blood supply represent the greatest interest in patients with acute cholecystitis. 3D-US allows estimating more precisely the degree and character of gallbladder wall structure and surrounding tissues infringement. 3D reconstruction of vessels gives the evident information of vascular pattern changes. 3D-US is not much more useful in gallbladder stones diagnosis than 2D one. 3D-US gives more information for differential diagnostics of gallbladder benign and malignant tumors, since it allows the visualization of granular surfaces of polypoid lesions and the pedunculated fundus.