Background: Three-dimensional EUS (3D-EUS) technology has facilitated spatial interpretation of US images. However, acquisition of consecutive US scans is time consuming and difficult. A new 3D-EUS system was developed that negates this problem by allowing rapid image renewal and the efficient production of consecutive US scans. Methods: Three-dimensional images were reconstructed from a series of 2-dimensional images corresponding to the rotation angle of the echoendoscope as measured with an electromagnetic tracking system. To evaluate the technical feasibility of the system, 3-dimensional images of splenic veins in 2 patients and an esophageal submucosal tumor in a third patient were generated. Results: The 3D-EUS system acquired image data at a rate of 30 frames per second and allowed visualization of these data in real-time. The area of interest was clearly and rapidly portrayed in all 3 patients. Conclusion: This study demonstrates the efficiency of the new 3D-EUS system described in this report. Further development of this novel 3D-EUS system may lead to new applications of this technology.