No abstract

This paper addresses a Moving Target Indication (MTI) algorithm which can be used for small Unmanned Aerial Vehicles (UAVs) equipped with image sensors. MTI is a system (or an algorithm) which detects moving objects. The principle of the MTI algorithm is to analyze the difference between successive image data. It is difficult to detect moving objects in the images recorded from dynamic cameras attached to moving platforms such as UAVs flying at low altitudes over a variety of terrain, since the acquired images have two motion components: 'camera motion' and 'object motion'. Therefore, the motion of independent objects can be obtained after the camera motion is compensated thoroughly via proper manipulations. In this study, the camera motion effects are removed by using wiener filter-based image registration, one of the non-parametric methods. In addition, an image pyramid structure is adopted to reduce the computational complexity for UAVs. We demonstrate the effectiveness of our method with experimental results on outdoor video sequences.

Background: Liver infections of Echinococcus multilocularis (EM) are rare in Germany. The optimal therapy of EM is surgical liver resection similar to malignant tumors. Methods: We describe the case of a 22-year-old patient who was diagnosed with increased liver enzymes during a routine checkup. Further radiologic diagnostics revealed an extended, cystic tumor of the liver with infiltration of left and middle hepatic vein and close contact to the right hepatic vein (RHV) and the inferior vena cava (VCI). Serologic tests confirmed the infection with EM. The patient was referred with the question of resectability after primary azole treatment. For a better preoperative evaluation, we performed a 3D reconstruction and resection planning. We combined this with 3D printing of the liver and the virtual display of the reconstruction in a virtual reality head mounted display (VR-HMD). For a curative and functional operation, resection of the VCI and reconstruction of the RHV seemed the only possibility. Results: We performed extended left hepatectomy with resection of segment 1, the extrahepatic bile duct, partial resection of the VCI and reconstruction with pericardial patch and end-to-end anastomosis of the segmentally resected RHV. The tumor was completely resected and histopathological analysis confirmed EM. Conclusion: In extended cases, the use of 3D reconstruction in combination with latest display methods such as VR-HMD or 3D printed models can improve surgical liver resection planning.