TY - CHAP A1 - Bourier, F. A1 - Schneider, H.-J. A1 - Ganslmeier, F. A1 - Heißenhuber, F. A1 - Fischer, R. A1 - Brost, A. A1 - Koch, M. A1 - Strobel, Norbert A1 - Hornegger, J. A1 - Kurzidim, K. T1 - Unterstützung der transseptalen Punktion durch vorherige Überlagerung eines 3D-Volumens von linkem Atrium und Aorta T2 - 77. Jahrestagung Frühjahrestagung der Gesellschaft für Kardiologie Mannheim 27.04. - 30.04.2011 Y1 - 2011 ER - TY - CHAP A1 - Koch, M. A1 - Langenkamp, A. A1 - Kiraly, A. A1 - Brost, A. A1 - Strobel, Norbert A1 - Hornegger, J. T1 - Navigation System with Contact Force Assessment to Guide Pulmonary Vein Isolation Procedures T2 - 23rd Conference of the Society for Medical Innovation and Technology (SMIT) Tel Aviv 01/2011 Y1 - 2011 UR - https://www5.informatik.uni-erlangen.de/Forschung/Publikationen/2011/Koch11-NSW.pdf UR - https://cris.fau.de/publications/113140984/ ER - TY - CHAP A1 - Bourier, F. A1 - Brost, A. A1 - Kleinoeder, A. A1 - Schneider, H.-J. A1 - Heißenhuber, F. A1 - Ganslmeier, P. A1 - Raab, J. A1 - Koch, M. A1 - Hornegger, J. A1 - Strobel, Norbert A1 - Kurzidim, K. T1 - 3D-Visualisation of Cryo-Balloon Ablation Catheters to Evaluate Left Atrial Anatomy for PVI T2 - Venice Arrhythmias 01/2011 Y1 - 2011 UR - https://cris.fau.de/publications/121376684/ ER - TY - CHAP A1 - Bourier, F. A1 - Schneider, H.-J. A1 - Heißenhuber, F. A1 - Ganslmeier, P. A1 - Brost, A. A1 - Koch, M. A1 - Hornegger, J. A1 - Kleinoeder, A. A1 - Kiraly, A. A1 - Barbot, J. A1 - Strobel, Norbert A1 - Kurzidim, K. T1 - Augmented Fluoroscopy to Guide Transseptal Puncture T2 - Venice Arrhythmias 2011 01/2011 Y1 - 2011 ER - TY - CHAP A1 - Bourier, F. A1 - Schneider, H.-J. A1 - Heißenhuber, F. A1 - Ganslmeier, P. A1 - Brost, A. A1 - Koch, M. A1 - Hornegger, J. A1 - Kleinoeder, A. A1 - Kiraly, A. A1 - Barbot, J. A1 - Strobel, Norbert A1 - Kurzidim, K. T1 - Pulmonary Vein Isolation guided by fluoroscopybased 3D-Navigation on a biplane angiography system T2 - Venice Arrhythmias 2011 01/2011 Y1 - 2011 ER - TY - JOUR A1 - Maier, Andreas A1 - Wigstrom, Lars A1 - Hofmann, Hannes G A1 - Hornegger, Joachim A1 - Zhu, Lei A1 - Strobel, Norbert A1 - Fahrig, Rebecca T1 - Three-dimensional anisotropic adaptive filtering of projection data for noise reduction in cone beam CT JF - Medical Physic N2 - Purpose: The combination of quickly rotating C-arm gantry with digital flat panel has enabled the acquisition of three-dimensional data (3D) in the interventional suite. However, image quality is still somewhat limited since the hardware has not been optimized for CT imaging. Adaptive anisotropic filtering has the ability to improve image quality by reducing the noise level and therewith the radiation dose without introducing noticeable blurring. By applying the filtering prior to 3D reconstruction, noise-induced streak artifacts are reduced as compared to processing in the image domain. Methods: 3D anisotropic adaptive filtering was used to process an ensemble of 2D x-ray views acquired along a circular trajectory around an object. After arranging the input data into a 3D space (2D projections + angle), the orientation of structures was estimated using a set of differently oriented filters. The resulting tensor representation of local orientation was utilized to control the anisotropic filtering. Low-pass filtering is applied only along structures to maintain high spatial frequency components perpendicular to these. The evaluation of the proposed algorithm includes numerical simulations, phantom experiments, and in-vivo data which were acquired using an AXIOM Artis dTA C-arm system (Siemens AG, Healthcare Sector, Forchheim, Germany). Spatial resolution and noise levels were compared with and without adaptive filtering. A human observer study was carried out to evaluate low-contrast detectability. Results: The adaptive anisotropic filtering algorithm was found to significantly improve low-contrast detectability by reducing the noise level by half (reduction of the standard deviation in certain areas from 74 to 30 HU). Virtually no degradation of high contrast spatial resolution was observed in the modulation transfer function (MTF) analysis. Although the algorithm is computationally intensive, hardware acceleration using Nvidia's CUDA Interface provided an 8.9-fold speed-up of the processing (from 1336 to 150 s). Conclusions: Adaptive anisotropic filtering has the potential to substantially improve image quality and/or reduce the radiation dose required for obtaining 3D image data using cone beam CT. Y1 - 2011 U6 - https://doi.org/10.1118/1.3633901 VL - 38 IS - 11 SP - 5896 EP - 5909 ER - TY - JOUR A1 - Yatziv, Liron A1 - Ibarz, Julian A1 - Strobel, Norbert A1 - Datta, Saurabh A1 - Sapiro, Guillermo T1 - Esophagus Silhouette Extraction and Reconstruction From Fluoroscopic Views for Cardiac Ablation Procedure Guidance JF - IEEE Transactions on Information Technology in Biomedicine N2 - Cardiac ablation involves the risk of serious complications when thermal injury to the esophagus occurs. This paper proposes to reduce the risk of such injuries by a proactive visualization technique, improving physician awareness of the esophagus location in the absence of or in addition to a reactive monitoring device such as a thermal probe. This is achieved by combining a graphical representation of the esophagus with live fluoroscopy. Toward this goal, we present an automated method to reconstruct and visualize a 3-D esophagus model from fluoroscopy image sequences acquired using different C-arm viewing directions. In order to visualize the esophagus under fluoroscopy, it is first biomarked by swallowing a contrast agent such as barium. Images obtained in this procedure are then used to automatically extract the 2-D esophagus silhouette and reconstruct a 3-D surface of the esophagus internal wall. Once the 3-D representation has been computed, it can be visualized using fluoroscopy overlay techniques. Compared to 3-D esophagus imaging using CT or C-arm CT, our proposed fluoroscopy method requires low radiation dose and enables a simpler workflow on geometry-calibrated standard C-arm systems. Y1 - 2011 U6 - https://doi.org/10.1109/TITB.2011.2162247 VL - 15 IS - 5 SP - 703 EP - 708 PB - IEEE ER - TY - CHAP A1 - Brost, Alexander A1 - Wu, Wen A1 - Koch, Martin A1 - Wimmer, Martin A1 - Chen, Terrence A1 - Liao, Rui A1 - Hornegger, Joachim A1 - Strobel, Norbert T1 - Combined Cardiac and Respiratory Motion Compensation for Atrial Fibrillation Ablation Procedures T2 - Medical Image Computing and Computer-Assisted Intervention N2 - Catheter ablation of atrial fibrillation has become an accepted treatment option if a patient no longer responds to or tolerates drug therapy. A main goal is the electrical isolation of the pulmonary veins attached to the left atrium. Catheter ablation may be performed under fluoroscopic image guidance. Due to the rather low soft-tissue contrast of X-ray imaging, the heart is not visible in these images. To overcome this problem, overlay images from pre-operative 3-D volumetric data can be used to add anatomical detail. Unfortunately, this overlay is compromised by respiratory and cardiac motion. In the past, two methods have been proposed to perform motion compensation. The first approach involves tracking of a circumferential mapping catheter placed at an ostium of a pulmonary vein. The second method relies on a motion estimate obtained by localizing an electrode of the coronary sinus (CS) catheter. We propose a new motion compensation scheme which combines these two methods. The effectiveness of the proposed method is verified using 19 real clinical data sets. The motion in the fluoroscopic images was estimated with an overall average error of 0.55 mm by tracking the circumferential mapping catheter. By applying an algorithm involving both the CS catheter and the circumferential mapping catheter, we were able to detect motion of the mapping catheter from one pulmonary vein to another with a false positive rate of 5.8 %. T3 - Lecture Notes in Computer Science - 6891 Y1 - 2011 SN - 978-3-642-23622-8 SN - 978-3-642-23623-5 U6 - https://doi.org/10.1007/978-3-642-23623-5_68 VL - 14 SP - 540 EP - 547 PB - Springer CY - Berlin, Heidelberg ER -