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Learning Soft Tissue Behavior of Organs for Surgical Navigation with Convolutional Neural Networks [article]

Micha Pfeiffer, Carina Riediger, Jürgen Weitz, Stefanie Speidel
2019 arXiv   pre-print
Purpose: In surgical navigation, pre-operative organ models are presented to surgeons during the intervention to help them in efficiently finding their target. In the case of soft tissue, these models need to be deformed and adapted to the current situation by using intra-operative sensor data. A promising method to realize this are real-time capable biomechanical models. Methods: We train a fully convolutional neural network to estimate a displacement field of all points inside an organ when
more » ... ven only the displacement of a part of the organ's surface. The network trains on entirely synthetic data of random organ-like meshes, which allows us to generate much more data than is otherwise available. The input and output data is discretized into a regular grid, allowing us to fully utilize the capabilities of convolutional operators and to train and infer in a highly parallelized manner. Results: The system is evaluated on in-silico liver models, phantom liver data and human in-vivo breathing data. We test the performance with varying material parameters, organ shapes and amount of visible surface. Even though the network is only trained on synthetic data, it adapts well to the various cases and gives a good estimation of the internal organ displacement. The inference runs at over 50 frames per second. Conclusions: We present a novel method for training a data-driven, real-time capable deformation model. The accuracy is comparable to other registration methods, it adapts very well to previously unseen organs and does not need to be re-trained for every patient. The high inferring speed makes this method useful for many applications such as surgical navigation and real-time simulation.
arXiv:1904.00722v1 fatcat:gp5sacxucbfdrgmhauwtluq7i4

Non-Rigid Volume to Surface Registration using a Data-Driven Biomechanical Model [article]

Micha Pfeiffer, Carina Riediger, Stefan Leger, Jens-Peter Kühn, Danilo Seppelt, Ralf-Thorsten Hoffmann, Jürgen Weitz, Stefanie Speidel
2020 arXiv   pre-print
Micha Pfeiffer 1 , 1 Carina Riediger 2 , Stefan Leger 1 , Jens-Peter Kühn 3 , Danilo Seppelt 3 , Ralf-Thorsten Hoffmann 3 , Jürgen Weitz 2 , and Stefanie Speidel 1 No Institute Given Fig. 1 . 1 Breathing  ... 
arXiv:2005.14695v1 fatcat:kqajqytddzdprkiddnwwfuq2hy

NKG2D Signaling Leads to NK Cell Mediated Lysis of Childhood AML

Patrick Schlegel, Kerstin Ditthard, Peter Lang, Markus Mezger, Sebastian Michaelis, Rupert Handgretinger, Matthias Pfeiffer
2015 Journal of Immunology Research  
grants from the Stiftung für krebskranke Kinder Tübingen e.V. and the Stefan-Morsch-Stiftung to Rupert Handgretinger and the Jose-Carreras Journal of Immunology Research 9 Leukaemia Foundation to Matthias Pfeiffer  ... 
doi:10.1155/2015/473175 pmid:26236752 pmcid:PMC4510257 fatcat:nx7xraguz5djxjti4jal34olq4

Long-Term Temporally Consistent Unpaired Video Translation from Simulated Surgical 3D Data [article]

Dominik Rivoir, Micha Pfeiffer, Reuben Docea, Fiona Kolbinger, Carina Riediger, Jürgen Weitz, Stefanie Speidel
2021 arXiv   pre-print
During training, texture features are projected into image space as a tex i which, combined with a simple rendering a ref i This is Pfeiffer et al.'  ...  Unpaired Image Translation Module Our translation module is a deterministic, style-less variant of Pfeiffer et al.'s model [38] , which itself is based on MUNIT [17] .  ... 
arXiv:2103.17204v2 fatcat:cvxfy7membgvtkpnpnr7m2xbfe

An Interactive Virtual Reality Environment for Analysis of Clinical Atrial Arrhythmias and Ablation Planning

Axel Loewe, Emanuel Poremba, Tobias G. Oesterlein, Nicolas Pilia, Micha Pfeiffer, Olaf Doessel, Stefanie Speidel
2017 2017 Computing in Cardiology Conference (CinC)  
Atrial arrhythmias like atrial fibrillation and atrial flutter are a major health challenge in developed countries. Radiofrequency ablation performed via intracardiac catheters is a curative therapy for these reentrant arrhythmias. However, the optimal location of ablation lesions is not straightforward to determine, particularly for complex activation patterns. Thus, a clinical need for tools to intuitively visualize complex activation patterns and to provide a platform to evaluate different
more » ... lation strategies in dry runs is apparent. Here, we present a virtual reality system that allows to interactively simulate atrial excitation propagation and place ablation lesions. Our software builds on the IMHOTEP framework for the Unity3D engine and implements a multithreaded model-view-controller design pattern. Excitation propagation is computed using a fast marching approach considering refractoriness. Interactive rewind and playback is supported through a combination of the flyweight pattern for simulation data with complete snapshots for key frames. The system was evaluated in a user study using the HTC Vive™ headset including two controllers. For high fidelity virtual reality interaction, a minimum frame rate of 60 per second is required. In a biatrial anatomical model comprising 36,059 nodes (Figure 1) , even complex activation patterns with multiple wavefronts could be simulated and rendered down to 2x slow motion (1 sec activation sequence displayed during 2 sec wall time) on a desktop machine. Results of the user study suggest added value regarding the comprehension of arrhythmias and ablation options and very good intuitiveness of the user interface requiring almost no teach-in. The virtual reality tool is ready to be used for educational purposes and prepared to import personalized models supporting diagnosis and therapy planning for atrial arrhythmias in the future.
doi:10.22489/cinc.2017.125-118 dblp:conf/cinc/LoewePOPPDS17 fatcat:4v2leugnznhpjpiobjaimngcoe

IMHOTEP: virtual reality framework for surgical applications

Micha Pfeiffer, Hannes Kenngott, Anas Preukschas, Matthias Huber, Lisa Bettscheider, Beat Müller-Stich, Stefanie Speidel
2018 International Journal of Computer Assisted Radiology and Surgery  
Purpose: The data which is available to surgeons before, during and after surgery is steadily increasing in quantity as well as diversity. When planning a patient's treatment, this large amount of information can be difficult to interpret. To aid in processing the information, new methods need to be found to present multi-modal patient data, ideally combining textual, imagery, temporal and 3D data in a holistic and context-aware system. Methods: We present an open-source framework which allows
more » ... andling of patient data in a virtual reality (VR) environment. By using VR technology, the workspace available to the surgeon is maximized and 3D patient data is rendered in stereo, which increases depth perception. The framework organizes the data into workspaces and contains tools which allow users to control, manipulate and enhance the data. Due to the framework's modular design, it can easily be adapted and extended for various clinical applications. Results: The framework was evaluated by clinical personnel (77 participants). The majority of the group stated that a complex surgical situation is easier to comprehend by using the framework, and that it is very well suited for education. Furthermore, the application to various clinical scenarios - including the simulation of excitation-propagation in the human atrium - demonstrated the framework's adaptability. As a feasibility study, the framework was used during the planning phase of the surgical removal of a large central carcinoma from a patient's liver. Conclusion: The clinical evaluation showed a large potential and high acceptance for the VR environment in a medical context. The various applications confirmed that the framework is easily extended and can be used in real-time simulation as well as for the manipulation of complex anatomical structures.
doi:10.1007/s11548-018-1730-x pmid:29551011 fatcat:gjpbdcvf6rcyfooa7vxdnrdzaq

Investigating the utility of VR for spatial understanding in surgical planning: evaluation of head-mounted to desktop display

Georges Hattab, Adamantini Hatzipanayioti, Anna Klimova, Micha Pfeiffer, Peter Klausing, Michael Breucha, Felix von Bechtolsheim, Jens R. Helmert, Jürgen Weitz, Sebastian Pannasch, Stefanie Speidel
2021 Scientific Reports  
AbstractRecent technological advances have made Virtual Reality (VR) attractive in both research and real world applications such as training, rehabilitation, and gaming. Although these other fields benefited from VR technology, it remains unclear whether VR contributes to better spatial understanding and training in the context of surgical planning. In this study, we evaluated the use of VR by comparing the recall of spatial information in two learning conditions: a head-mounted display (HMD)
more » ... nd a desktop screen (DT). Specifically, we explored (a) a scene understanding and then (b) a direction estimation task using two 3D models (i.e., a liver and a pyramid). In the scene understanding task, participants had to navigate the rendered the 3D models by means of rotation, zoom and transparency in order to substantially identify the spatial relationships among its internal objects. In the subsequent direction estimation task, participants had to point at a previously identified target object, i.e., internal sphere, on a materialized 3D-printed version of the model using a tracked pointing tool. Results showed that the learning condition (HMD or DT) did not influence participants' memory and confidence ratings of the models. In contrast, the model type, that is, whether the model to be recalled was a liver or a pyramid significantly affected participants' memory about the internal structure of the model. Furthermore, localizing the internal position of the target sphere was also unaffected by participants' previous experience of the model via HMD or DT. Overall, results provide novel insights on the use of VR in a surgical planning scenario and have paramount implications in medical learning by shedding light on the mental model we make to recall spatial structures.
doi:10.1038/s41598-021-92536-x pmid:34188080 fatcat:r7rixxezgfdyfohkcxshia55b4

Page 1225 of Journal of the Chemical Society Vol. 83-102, Issue CUMULATIVE INDEX [page]

1903 Journal of the Chemical Society  
., ii, 625. sensitiveness of, towards’ lime (PFEIFFER and BLaANnck), 1911, A., ii, 761. yellow, cultivation of (DkHERAIN and Demoussy), 1903, A., ii, 37.  ...  Lutidinobromoindazole (MICHAELIS and MUHLBERG), 1909, A., i, 533. Lutidino-3-bromo-2-8-naphthylindazole (MICHAELIS and KRIETEMEYER),1909, A., i, 534.  ... 

Über die Mitwirkung elektrokapillarer Effekte bei der Vitalfärbung pflanzlicher und tierischer Protoplasten

1927 Protoplasma  
In Ubereinstimmung mit Collander findet Pfeiffer, daft die yon Michaelis, Fuiita und D o k an erarbeiteten Vorstellungen fiber die Ionenaufnahme dutch Membranen, als welche die Plasmagrenzfliiche bier  ...  Pfeiffer, Heinri~h, Uber die Mitwirkung elektro-kapillarer Effekte bet der VitalfKrbung pflanzlicher und tierischer Protoplasten. Biolog. Zentralbl. 47, 201, 1927 .  ... 
doi:10.1007/bf01604768 fatcat:ah2uallibjg3fmsmkw7jb3nrea

Page 125 of Biological Chemistry Vol. 140, Issue [page]

1924 Biological Chemistry  
Siehe hierzu auch Michaelis _ Monogr., 2. Aufl., S. 121.  ...  . : Pfeiffer und neuerdings Pfeiffer und Angern haben nit Erfolg Gemische von Aminosiiuren durch Salzzusatz zu a trennen versucht, und es ist zu erwarten, daB sich bei niherer Ausarbeitung, die Pfeiffer  ... 

VII. Karlsburg Symposium on Problems of Diabetes, September 29 to October 1, 1971

1972 Diabetologia  
Federlin, K., Pfeiffer, E.F., U]m/GFR: Immunological aspects in diabetes mMlitus.  ...  Sehatz, H., Hinz, M., MMer, V., Katsilambros, N., Pfeiffer, E.F., Ulm/GFR: Influencing insulin biosynthesis and secretion in the isolated Langerhans islet model.  ... 
doi:10.1007/bf01225578 fatcat:svyrj5s23vc7vonibj2rppn7ku

Page 145 of The Lutheran Quarterly Vol. 55, Issue 2 [page]

1925 The Lutheran Quarterly  
Michaelis, M. Georg Michaelis, Johan- nes Moller, J. Lorentz Mosheim, Joh. Miiller, Joh. Cas- par Muerdel. Caspar Neuman, Sebastian Neumann, Erdmann Neu- meister, Elbertus Noordbeck.  ...  Pfeiffer, Georg Mich. Pfeffer- korn, Georg G. Pitzschmann, Heinrich Pipping, Peter Poiret, Elias Praetorius, Joh. Praetorius, Andr. Pruck- ner. Joh. Quistorp. Joh.  ... 

Page 398 of New York Academy of Sciences. Transactions of the New York Academy of Sciences Vol. 28, Issue 3 [page]

1966 New York Academy of Sciences. Transactions of the New York Academy of Sciences  
Hofmann (1857) 3 PhBr + SbCl3 + 6 Na »■ PhgSb + 6 NaBr Michaelis (1882) 3 PhMgBr + SbClg-►PhgSb + 3 MgBrCl Pfeiffer (1904); (Kocheshkov with PhLi) 3 RgAl + SbFg-►RsSb + 3 R2AIF Jenkner (Kali Chemie; 1956  ... 

Page 340 of The Biochemical Journal Vol. 7, Issue 3 [page]

1913 The Biochemical Journal  
Michaelis (1909), Biochem. Zeitsch. 19, 181. and Mostynski (1910), Biochem. Zeitsch. 24, 79. —— and Rona (1910, 1), Biochem. Zeitsch. 27, 38. — — (1910, 2), Biochem. Zeitsch. 28, 193.  ...  Pfeiffer and Modelski (1912), Zeitsch. physiol. Chem. 81, 329. Schryver (1910), Proc. Roy. Soc. B, 83, 96. Sérensen and Jurgensen (1911), Biochem. Zeitsch. 31, 397. Starke (1900), Zeitsch.  ... 

Page 864 of Journal of the Chemical Society Vol. 125, Issue [page]

1924 Journal of the Chemical Society  
preparation of triphenylphosphine from phosphorus trichloride and magnesium phenyl bromide, we have observed the production of the oxide, which was not detected by Sauvage (Compt. rend., 1904, 139, 675) or by Pfeiffer  ...  TxE formation of compounds of the type R,MX, is well known in connexion with the Michaelis and Reese reaction (compare Annalen, 1886, 233, 45, 60), but very few instances have been recorded in the case  ... 
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