@article{ZinserZachowSailer2013, author = {Zinser, Max and Zachow, Stefan and Sailer, Hermann}, title = {Bimaxillary "rotation advancement" procedures in patients with obstructive sleep apnea: A 3-dimensional airway analysis of morphological changes}, series = {International Journal of Oral \& Maxillofacial Surgery}, volume = {42}, journal = {International Journal of Oral \& Maxillofacial Surgery}, number = {5}, doi = {10.1016/j.ijom.2012.08.002}, pages = {569 -- 578}, year = {2013}, language = {en} } @inproceedings{ZilskeLameckerZachow2008, author = {Zilske, Michael and Lamecker, Hans and Zachow, Stefan}, title = {Adaptive Remeshing of Non-Manifold Surfaces}, series = {Eurographics 2008 Annex to the Conf. Proc.}, booktitle = {Eurographics 2008 Annex to the Conf. Proc.}, pages = {207 -- 211}, year = {2008}, language = {en} } @misc{ZilskeLameckerZachow, author = {Zilske, Michael and Lamecker, Hans and Zachow, Stefan}, title = {Adaptive Remeshing of Non-Manifold Surfaces}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-9445}, number = {07-01}, abstract = {We present a unified approach for consistent remeshing of arbitrary non-manifold triangle meshes with additional user-defined feature lines, which together form a feature skeleton. Our method is based on local operations only and produces meshes of high regularity and triangle quality while preserving the geometry as well as topology of the feature skeleton and the input mesh.}, language = {en} } @article{ZeilhoferZachowFairleyetal.2000, author = {Zeilhofer, Hans-Florian and Zachow, Stefan and Fairley, Jeffrey and Sader, Robert and Deuflhard, Peter}, title = {Treatment Planning and Simulation in Craniofacial Surgery with Virtual Reality Techiques}, series = {Journal of Cranio-Maxillofacial Surgery}, volume = {28 (Suppl. 1)}, journal = {Journal of Cranio-Maxillofacial Surgery}, pages = {82}, year = {2000}, language = {en} } @article{ZahnGrotjohannRammetal., author = {Zahn, Robert and Grotjohann, Sarah and Ramm, Heiko and Zachow, Stefan and Putzier, Michael and Perka, Carsten and Tohtz, Stephan}, title = {Pelvic tilt compensates for increased acetabular anteversion}, series = {International Orthopaedics}, volume = {40}, journal = {International Orthopaedics}, number = {8}, doi = {10.1007/s00264-015-2949-6}, pages = {1571 -- 1575}, abstract = {Pelvic tilt determines functional orientation of the acetabulum. In this study, we investigated the interaction of pelvic tilt and functional acetabular anteversion (AA) in supine position.}, language = {en} } @article{ZahnGrotjohannRammetal., author = {Zahn, Robert and Grotjohann, Sarah and Ramm, Heiko and Zachow, Stefan and Pumberger, Matthias and Putzier, Michael and Perka, Carsten and Tohtz, Stephan}, title = {Influence of pelvic tilt on functional acetabular orientation}, series = {Technology and Health Care}, volume = {25}, journal = {Technology and Health Care}, number = {3}, publisher = {IOS Press}, doi = {10.3233/THC-161281}, pages = {557 -- 565}, language = {en} } @misc{ZachowZilskeHege, author = {Zachow, Stefan and Zilske, Michael and Hege, Hans-Christian}, title = {3D reconstruction of individual anatomy from medical image data: Segmentation and geometry processing}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-10440}, number = {07-41}, abstract = {For medical diagnosis, visualization, and model-based therapy planning three-dimensional geometric reconstructions of individual anatomical structures are often indispensable. Computer-assisted, model-based planning procedures typically cover specific modifications of "virtual anatomy" as well as numeric simulations of associated phenomena, like e.g. mechanical loads, fluid dynamics, or diffusion processes, in order to evaluate a potential therapeutic outcome. Since internal anatomical structures cannot be measured optically or mechanically in vivo, three-dimensional reconstruction of tomographic image data remains the method of choice. In this work the process chain of individual anatomy reconstruction is described which consists of segmentation of medical image data, geometrical reconstruction of all relevant tissue interfaces, up to the generation of geometric approximations (boundary surfaces and volumetric meshes) of three-dimensional anatomy being suited for finite element analysis. All results presented herein are generated with amira ® - a highly interactive software system for 3D data analysis, visualization and geometry reconstruction.}, language = {en} } @inproceedings{ZachowZilskeHege2007, author = {Zachow, Stefan and Zilske, Michael and Hege, Hans-Christian}, title = {3D Reconstruction of Individual Anatomy from Medical Image Data: Segmentation and Geometry Processing}, series = {25. ANSYS Conference \& CADFEM Users' Meeting}, booktitle = {25. ANSYS Conference \& CADFEM Users' Meeting}, address = {Dresden}, year = {2007}, language = {en} } @incollection{ZachowWeiserHegeetal.2005, author = {Zachow, Stefan and Weiser, Martin and Hege, Hans-Christian and Deuflhard, Peter}, title = {Soft Tissue Prediction in Computer Assisted Maxillofacial Surgery Planning}, series = {Biomechanics Applied to Computer Assisted Surgery}, booktitle = {Biomechanics Applied to Computer Assisted Surgery}, editor = {Payan, Y.}, publisher = {Research Signpost}, pages = {277 -- 298}, year = {2005}, language = {en} } @incollection{ZachowWeiserDeuflhard2008, author = {Zachow, Stefan and Weiser, Martin and Deuflhard, Peter}, title = {Modellgest{\"u}tzte Operationsplanung in der Kopfchirurgie}, series = {Modellgest{\"u}tzte Therapie}, booktitle = {Modellgest{\"u}tzte Therapie}, editor = {Niederlag, Wolfgang and Lemke, Heinz and Meixensberger, J{\"u}rgen and Baumann, Michael}, publisher = {Health Academy}, pages = {140 -- 156}, year = {2008}, language = {en} } @article{ZachowSteinmannHildebrandtetal.2006, author = {Zachow, Stefan and Steinmann, Alexander and Hildebrandt, Thomas and Weber, Rainer and Heppt, Werner}, title = {CFD simulation of nasal airflow: Towards treatment planning for functional rhinosurgery}, series = {Int. J. of Computer Assisted Radiology and Surgery}, journal = {Int. J. of Computer Assisted Radiology and Surgery}, publisher = {Springer}, pages = {165 -- 167}, year = {2006}, language = {en} } @article{ZachowSteinmannHildebrandtetal.2007, author = {Zachow, Stefan and Steinmann, Alexander and Hildebrandt, Thomas and Heppt, Werner}, title = {Understanding nasal airflow via CFD simulation and visualization}, series = {Proc. Computer Aided Surgery around the Head}, journal = {Proc. Computer Aided Surgery around the Head}, pages = {173 -- 176}, year = {2007}, language = {en} } @article{ZachowMuiggHildebrandtetal.2009, author = {Zachow, Stefan and Muigg, Philipp and Hildebrandt, Thomas and Doleisch, Helmut and Hege, Hans-Christian}, title = {Visual Exploration of Nasal Airflow}, series = {IEEE Transactions on Visualization and Computer Graphics}, volume = {15}, journal = {IEEE Transactions on Visualization and Computer Graphics}, number = {8}, doi = {10.1109/TVCG.2009.198}, pages = {1407 -- 1414}, year = {2009}, language = {en} } @inproceedings{ZachowLuethStallingetal.1999, author = {Zachow, Stefan and Lueth, Tim and Stalling, Detlev and Hein, Andreas and Klein, Martin and Menneking, Horst}, title = {Optimized Arrangement of Osseointegrated Implants: A Surgical Planning System for the Fixation of Facial Protheses}, series = {Computer Assisted Radiology and Surgery (CARS'99)}, booktitle = {Computer Assisted Radiology and Surgery (CARS'99)}, publisher = {Elsevier Science B.V.}, pages = {942 -- 946}, year = {1999}, language = {en} } @article{ZachowLameckerZoeckleretal.2009, author = {Zachow, Stefan and Lamecker, Hans and Z{\"o}ckler, Maja and Haberl, Ernst}, title = {Computergest{\"u}tzte Planung zur chirurgischen Korrektur von fr{\"u}hkindlichen Sch{\"a}delfehlbildungen (Craniosynostosen)}, series = {Face 02/09, Int. Mag. of Orofacial Esthetics, Oemus Journale Leipzig}, journal = {Face 02/09, Int. Mag. of Orofacial Esthetics, Oemus Journale Leipzig}, pages = {48 -- 53}, year = {2009}, language = {en} } @inproceedings{ZachowLameckerElsholtzetal.2005, author = {Zachow, Stefan and Lamecker, Hans and Elsholtz, Barbara and Stiller, Michael}, title = {Reconstruction of mandibular dysplasia using a statistical 3D shape model}, series = {Proc. Computer Assisted Radiology and Surgery (CARS)}, booktitle = {Proc. Computer Assisted Radiology and Surgery (CARS)}, address = {Berlin, Germany}, doi = {10.1016/j.ics.2005.03.339}, pages = {1238 -- 1243}, year = {2005}, language = {en} } @article{ZachowLameckerElsholtzetal.2006, author = {Zachow, Stefan and Lamecker, Hans and Elsholtz, Barbara and Stiller, Michael}, title = {Is the course of the mandibular nerve deducible from the shape of the mandible?}, series = {Int. J. of Computer Assisted Radiology and Surgery}, journal = {Int. J. of Computer Assisted Radiology and Surgery}, publisher = {Springer}, pages = {415 -- 417}, year = {2006}, language = {en} } @inproceedings{ZachowKubiackMalinowskietal.2010, author = {Zachow, Stefan and Kubiack, Kim and Malinowski, Jana and Lamecker, Hans and Essig, Harald and Gellrich, Nils-Claudius}, title = {Modellgest{\"u}tzte chirurgische Rekonstruktion komplexer Mittelgesichtsfrakturen}, series = {Proc. BMT, Biomed Tech 2010}, volume = {55 (Suppl 1)}, booktitle = {Proc. BMT, Biomed Tech 2010}, publisher = {Walter de Gruyter-Verlag}, pages = {107 -- 108}, year = {2010}, language = {de} } @inproceedings{ZachowHierlErdmann2004, author = {Zachow, Stefan and Hierl, Thomas and Erdmann, Bodo}, title = {A quantitative evaluation of 3D soft tissue prediction in maxillofacial surgery planning}, series = {Proc. 3. Jahrestagung der Deutschen Gesellschaft f{\"u}r Computer- und Roboter-assistierte Chirurgie e.V.}, booktitle = {Proc. 3. Jahrestagung der Deutschen Gesellschaft f{\"u}r Computer- und Roboter-assistierte Chirurgie e.V.}, address = {M{\"u}nchen}, year = {2004}, language = {en} } @inproceedings{ZachowHierlErdmann2004, author = {Zachow, Stefan and Hierl, Thomas and Erdmann, Bodo}, title = {On the Predictability of tissue changes after osteotomy planning in maxillofacial surgery}, series = {Computer Assisted Radiology and Surgery (CARS)}, booktitle = {Computer Assisted Radiology and Surgery (CARS)}, address = {Chicago, USA}, doi = {10.1016/j.ics.2004.03.043}, pages = {648 -- 653}, year = {2004}, language = {en} } @inproceedings{ZachowHierlErdmann2004, author = {Zachow, Stefan and Hierl, Thomas and Erdmann, Bodo}, title = {{\"U}ber die Genauigkeit einer 3D Weichgewebepr{\"a}diktion in der MKG-Cirurgie}, series = {Workshop 'Bildverarbeitung f{\"u}r die Medizin' (BVM)}, booktitle = {Workshop 'Bildverarbeitung f{\"u}r die Medizin' (BVM)}, address = {Berlin, Germany}, pages = {75 -- 79}, year = {2004}, language = {en} } @article{ZachowHeppt, author = {Zachow, Stefan and Heppt, Werner}, title = {The Facial Profile}, series = {Facial Plastic Surgery}, volume = {31}, journal = {Facial Plastic Surgery}, number = {5}, doi = {10.1055/s-0035-1566132}, pages = {419 -- 420}, abstract = {Facial appearance in our societies is often associated with notions of attractiveness, juvenileness, beauty, success, and so forth. Hence, the role of facial plastic surgery is highly interrelated to a patient's desire to feature many of these positively connoted attributes, which of course, are subject of different cultural perceptions or social trends. To judge about somebody's facial appearance, appropriate quantitative measures as well as methods to obtain and compare individual facial features are required. This special issue on facial profile is intended to provide an overview on how facial characteristics are surgically managed in an interdisciplinary way based on experience, instrumentation, and modern technology to obtain an aesthetic facial appearance with harmonious facial proportions. The facial profile will be discussed within the context of facial aesthetics. Latest concepts for capturing facial morphology in high speed and impressive detail are presented for quantitative analysis of even subtle changes, aging effects, or facial expressions. In addition, the perception of facial profiles is evaluated based on eye tracking technology.}, language = {en} } @article{ZachowHegeDeuflhard2005, author = {Zachow, Stefan and Hege, Hans-Christian and Deuflhard, Peter}, title = {Maxillofacial surgery planning with 3D soft tissue prediction - modeling, planning, simulation}, series = {2. Int. Conf. on Advanced Digital Technology in Head and Neck Reconstruction, Abstract 33}, journal = {2. Int. Conf. on Advanced Digital Technology in Head and Neck Reconstruction, Abstract 33}, address = {Banff, Alberta, CA}, pages = {64}, year = {2005}, language = {en} } @inproceedings{ZachowHegeDeuflhard2004, author = {Zachow, Stefan and Hege, Hans-Christian and Deuflhard, Peter}, title = {Computergest{\"u}tzte Operationsplanung in der Gesichtschirurgie}, series = {Proc. VDE Kongress 2004 - Innovationen f{\"u}r Menschen, Band 2, Fachtagungsberichte DGBMT - GMM - GMA}, booktitle = {Proc. VDE Kongress 2004 - Innovationen f{\"u}r Menschen, Band 2, Fachtagungsberichte DGBMT - GMM - GMA}, pages = {53 -- 58}, year = {2004}, language = {en} } @article{ZachowHegeDeuflhard2006, author = {Zachow, Stefan and Hege, Hans-Christian and Deuflhard, Peter}, title = {Computer assisted planning in cranio-maxillofacial surgery}, series = {Journal of Computing and Information Technology}, volume = {14(1)}, journal = {Journal of Computing and Information Technology}, pages = {53 -- 64}, year = {2006}, language = {en} } @incollection{ZachowHahnLange2010, author = {Zachow, Stefan and Hahn, Horst and Lange, Thomas}, title = {Computerassistierte Chirugieplanung}, series = {Computerassistierte Chirurgie}, booktitle = {Computerassistierte Chirurgie}, editor = {Schlag, Peter and Eulenstein, Sebastian and Lange, Thomas}, publisher = {Elsevier}, pages = {119 -- 149}, year = {2010}, language = {en} } @inproceedings{ZachowGladilinZeilhoferetal.2001, author = {Zachow, Stefan and Gladilin, Evgeny and Zeilhofer, Hans-Florian and Sader, Robert}, title = {Improved 3D Osteotomy Planning in Cranio-Maxillofacial Surgery}, series = {Proc. Medical Image Computing and Computer-Assisted Intervention (MICCAI 2001)}, booktitle = {Proc. Medical Image Computing and Computer-Assisted Intervention (MICCAI 2001)}, address = {Utrecht, The Netherlands}, doi = {10.1007/3-540-45468-3_57}, pages = {473 -- 481}, year = {2001}, language = {en} } @inproceedings{ZachowGladilinZeilhoferetal.2001, author = {Zachow, Stefan and Gladilin, Evgeny and Zeilhofer, Hans-Florian and Sader, Robert}, title = {3D Osteotomieplanung in der MKG-Chirurgie unter Ber{\"u}cksichtigung der r{\"a}umlichen Weichgewebeanordnung}, series = {Rechner- und sensorgest{\"u}tzte Chirurgie, GI Proc. zur SFB 414 Tagung}, booktitle = {Rechner- und sensorgest{\"u}tzte Chirurgie, GI Proc. zur SFB 414 Tagung}, address = {Heidelberg}, pages = {217 -- 226}, year = {2001}, language = {en} } @article{ZachowGladilinTrepczynskietal.2002, author = {Zachow, Stefan and Gladilin, Evgeny and Trepczynski, Adam and Sader, Robert and Zeilhofer, Hans-Florian}, title = {3D Osteotomy Planning in Cranio-Maxillofacial Surgery: Experiences and Results of Surgery Planning and Volumetric Finite-Element Soft Tissue Prediction in Three Clinical Cases}, series = {Computer Assisted Radiology and Surgery (CARS)}, journal = {Computer Assisted Radiology and Surgery (CARS)}, publisher = {Springer Verlag}, pages = {983 -- 987}, year = {2002}, language = {en} } @inproceedings{ZachowGladilinSaderetal.2003, author = {Zachow, Stefan and Gladilin, Evgeny and Sader, Robert and Zeilhofer, Hans-Florian}, title = {Draw \& Cut: Intuitive 3D Osteotomy Planning on Polygonal Bone Models}, series = {Computer Assisted Radiology and Surgery (CARS)}, booktitle = {Computer Assisted Radiology and Surgery (CARS)}, address = {London, UK}, doi = {10.1016/S0531-5131(03)00272-3}, pages = {362 -- 369}, year = {2003}, language = {en} } @inproceedings{ZachowGladilinHegeetal.2002, author = {Zachow, Stefan and Gladilin, Evgeny and Hege, Hans-Christian and Deuflhard, Peter}, title = {Towards Patient Specific, Anatomy Based Simulation of Facial Mimics for Surgical Nerve Rehabilitation}, series = {Computer Assisted Radiology and Surgery (CARS)}, booktitle = {Computer Assisted Radiology and Surgery (CARS)}, publisher = {Springer Verlag}, pages = {3 -- 6}, year = {2002}, language = {en} } @inproceedings{ZachowGladilinHegeetal.2000, author = {Zachow, Stefan and Gladilin, Evgeny and Hege, Hans-Christian and Deuflhard, Peter}, title = {Finite-Element Simulation of Soft Tissue Deformation}, series = {Computer Assisted Radiology and Surgey (CARS)}, booktitle = {Computer Assisted Radiology and Surgey (CARS)}, publisher = {Elsevier Science B.V.}, pages = {23 -- 28}, year = {2000}, language = {en} } @inproceedings{ZachowErdmannHegeetal.2004, author = {Zachow, Stefan and Erdmann, Bodo and Hege, Hans-Christian and Deuflhard, Peter}, title = {Advances in 3D osteotomy planning with 3D soft tissue prediction}, series = {Proc. 2nd International Symposium on Computer Aided Surgery around the Head, Abstract}, booktitle = {Proc. 2nd International Symposium on Computer Aided Surgery around the Head, Abstract}, address = {Bern}, pages = {31}, year = {2004}, language = {en} } @article{ZachowDeuflhard2008, author = {Zachow, Stefan and Deuflhard, Peter}, title = {Computergest{\"u}tzte Planung in der kraniofazialen Chirurgie}, series = {Face 01/08, Int. Mag. of Orofacial Esthetics}, journal = {Face 01/08, Int. Mag. of Orofacial Esthetics}, publisher = {Oemus Journale Leipzig}, pages = {43 -- 49}, year = {2008}, language = {en} } @phdthesis{Zachow, author = {Zachow, Stefan}, title = {Computergest{\"u}tzte 3D Osteotomieplanung in der Mund-Kiefer-Gesichtschirurgie unter Ber{\"u}cksichtigung der r{\"a}umlichen Weichgewebeanordnung}, isbn = {3899631986}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-10432}, abstract = {In der Arbeit wird die computergest{\"u}tzte Planung von chirurgisch gesetzten Knochenfrakturen bzw. Knochenschnitten (sogenannten Osteotomien) an dreidimensionalen, computergrafischen Sch{\"a}delmodellen, sowie die Umpositionierung separierter kn{\"o}cherner Segmente im Kontext der rekonstruktiven MKG-Chirurgie behandelt. Durch die 3D Modellierung und Visualisierung anatomischer Strukturen, sowie der 3D Osteotomie- und Umstellungsplanung unter Einbeziehung der resultierenden Weichgewebedeformation wird den Chirurgen ein Werkzeug an die Hand gegeben, mit dem eine Therapieplanung am Computer durchgef{\"u}hrt und diese in Hinblick auf Funktion und {\"A}sthetik bewertet werden kann. Unterschiedliche Strategien k{\"o}nnen dabei erprobt und in ihrer Auswirkung erfasst werden. Dazu wird ein methodischer Ansatz vorgestellt, der zum einen die chirurgische Planung im Vergleich zu existierenden Ans{\"a}tzen deutlich verbessert und zum anderen eine robuste Weichgewebeprognose, durch den Einsatz geeigneter Planungsmodelle und eines physikalisch basierten Weichgewebemodells unter Nutzung numerischer L{\"o}sungsverfahren in die Planung integriert. Die Visualisierung der Planungsergebnisse erlaubt sowohl eine anschauliche und {\"u}berzeugende, pr{\"a}operative Patientenaufkl{\"a}rung, als auch die Demonstration m{\"o}glicher Vorgehensweisen und deren Auswirkungen f{\"u}r die chirurgische Ausbildung. Ferner erg{\"a}nzen die Planungsdaten die Falldokumentation und liefern einen Beitrag zur Qualit{\"a}tssicherung. Die Arbeit ist in sieben Kapitel gegliedert und wie folgt strukturiert: Zuerst wird die medizinische Aufgabenstellung bei der chirurgischen Rekonstruktion von Knochenfehlbildungen und -fehlstellungen in der kraniofazialen Chirurgie sowie die daraus resultierenden Anforderungen an die Therapieplanung beschrieben. Anschließend folgt ein umfassender {\"U}berblick {\"u}ber entsprechende Vorarbeiten zur computergest{\"u}tzten Planung knochenverlagernder Operationen und eine kritische Bestandsaufnahme der noch vorhandenen Defizite. Nach der Vorstellung des eigenen Planungsansatzes wird die Generierung individueller, qualitativ hochwertiger 3D Planungsmodelle aus tomografischen Bilddaten beschrieben, die den Anforderungen an eine intuitive, 3D Planung von Umstellungsosteotomien entsprechen und eine Simulation der daraus resultierenden Weichgewebedeformation mittels der Finite-Elemente Methode (FEM) erm{\"o}glichen. Die Methoden der 3D Schnittplanung an computergrafischen Modellen werden analysiert und eine 3D Osteotomieplanung an polygonalen Sch{\"a}delmodellen entwickelt, die es erm{\"o}glicht, intuitiv durch Definition von Schnittlinien am 3D Knochenmodell, eine den chirurgischen Anforderungen entsprechende Schnittplanung unter Ber{\"u}cksichtigung von Risikostrukturen durchzuf{\"u}hren. Separierte Knochensegmente lassen sich im Anschluss interaktiv umpositionieren und die resultierende Gesamtanordnung hinsichtlich einer funktionellen Rehabilitation bewerten. Aufgrund des in dieser Arbeit gew{\"a}hlten, physikalisch basierten Modellierungsansatzes kann unter Ber{\"u}cksichtigung des gesamten Weichgewebevolumens aus der Knochenverlagerung direkt die resultierende Gesichtsform berechnet werden. Dies wird anhand von 13 exemplarischen Fallstudien anschaulich demonstriert, wobei die Prognosequalit{\"a}t mittels postoperativer Fotografien und postoperativer CT-Daten {\"u}berpr{\"u}ft und belegt wird. Die Arbeit wird mit einem Ausblick auf erweiterte Modellierungsans{\"a}tze und einem Konzept f{\"u}r eine integrierte, klinisch einsetzbare Planungsumgebung abgeschlossen.}, language = {de} } @misc{Zachow1999, type = {Master Thesis}, author = {Zachow, Stefan}, title = {Design and Implementation of a planning system for episthetic surgery}, year = {1999}, language = {en} } @phdthesis{Zachow2005, author = {Zachow, Stefan}, title = {Computer assisted osteotomy planning in cranio-maxillofacial surgery under consideration of facial soft tissue changes}, year = {2005}, language = {en} } @article{Zachow, author = {Zachow, Stefan}, title = {Computational Planning in Facial Surgery}, series = {Facial Plastic Surgery}, volume = {31}, journal = {Facial Plastic Surgery}, number = {5}, doi = {10.1055/s-0035-1564717}, pages = {446 -- 462}, abstract = {This article reflects the research of the last two decades in computational planning for cranio-maxillofacial surgery. Model-guided and computer-assisted surgery planning has tremendously developed due to ever increasing computational capabilities. Simulators for education, planning, and training of surgery are often compared with flight simulators, where maneuvers are also trained to reduce a possible risk of failure. Meanwhile, digital patient models can be derived from medical image data with astonishing accuracy and thus can serve for model surgery to derive a surgical template model that represents the envisaged result. Computerized surgical planning approaches, however, are often still explorative, meaning that a surgeon tries to find a therapeutic concept based on his or her expertise using computational tools that are mimicking real procedures. Future perspectives of an improved computerized planning may be that surgical objectives will be generated algorithmically by employing mathematical modeling, simulation, and optimization techniques. Planning systems thus act as intelligent decision support systems. However, surgeons can still use the existing tools to vary the proposed approach, but they mainly focus on how to transfer objectives into reality. Such a development may result in a paradigm shift for future surgery planning.}, language = {en} } @misc{WilsonBuecherGreweetal., author = {Wilson, David and B{\"u}cher, Pia and Grewe, Carl Martin and Mocanu, Valentin and Anglin, Carolyn and Zachow, Stefan and Dunbar, Michael}, title = {Validation of Three Dimensional Models of the Distal Femur Created from Surgical Navigation Data}, series = {Orthopedic Research Society Annual Meeting}, journal = {Orthopedic Research Society Annual Meeting}, address = {Las Vegas, Nevada}, language = {en} } @misc{WilsonBuecherGreweetal., author = {Wilson, David and B{\"u}cher, Pia and Grewe, Carl Martin and Anglin, Carolyn and Zachow, Stefan and Michael, Dunbar}, title = {Validation of Three Dimensional Models of the Distal Femur Created from Surgical Navigation Point Cloud Data}, series = {15th Annual Meeting of the International Society for Computer Assisted Orthopaedic Surgery (CAOS)}, journal = {15th Annual Meeting of the International Society for Computer Assisted Orthopaedic Surgery (CAOS)}, language = {en} } @article{WilsonAnglinAmbellanetal., author = {Wilson, David and Anglin, Carolyn and Ambellan, Felix and Grewe, Carl Martin and Tack, Alexander and Lamecker, Hans and Dunbar, Michael and Zachow, Stefan}, title = {Validation of three-dimensional models of the distal femur created from surgical navigation point cloud data for intraoperative and postoperative analysis of total knee arthroplasty}, series = {International Journal of Computer Assisted Radiology and Surgery}, volume = {12}, journal = {International Journal of Computer Assisted Radiology and Surgery}, number = {12}, publisher = {Springer}, doi = {10.1007/s11548-017-1630-5}, pages = {2097 -- 2105}, abstract = {Purpose: Despite the success of total knee arthroplasty there continues to be a significant proportion of patients who are dissatisfied. One explanation may be a shape mismatch between pre and post-operative distal femurs. The purpose of this study was to investigate a method to match a statistical shape model (SSM) to intra-operatively acquired point cloud data from a surgical navigation system, and to validate it against the pre-operative magnetic resonance imaging (MRI) data from the same patients. Methods: A total of 10 patients who underwent navigated total knee arthroplasty also had an MRI scan less than 2 months pre-operatively. The standard surgical protocol was followed which included partial digitization of the distal femur. Two different methods were employed to fit the SSM to the digitized point cloud data, based on (1) Iterative Closest Points (ICP) and (2) Gaussian Mixture Models (GMM). The available MRI data were manually segmented and the reconstructed three-dimensional surfaces used as ground truth against which the statistical shape model fit was compared. Results: For both approaches, the difference between the statistical shape model-generated femur and the surface generated from MRI segmentation averaged less than 1.7 mm, with maximum errors occurring in less clinically important areas. Conclusion: The results demonstrated good correspondence with the distal femoral morphology even in cases of sparse data sets. Application of this technique will allow for measurement of mismatch between pre and post-operative femurs retrospectively on any case done using the surgical navigation system and could be integrated into the surgical navigation unit to provide real-time feedback.}, language = {en} } @article{WestermarkZachowEppley2005, author = {Westermark, Anders and Zachow, Stefan and Eppley, Barry}, title = {3D osteotomy planning in maxillofacial surgery, including 3D soft tissue prediction}, series = {Journal of Craniofacial Surgery}, volume = {16(1)}, journal = {Journal of Craniofacial Surgery}, pages = {100 -- 104}, year = {2005}, language = {en} } @article{WeiserZachowDeuflhard2010, author = {Weiser, Martin and Zachow, Stefan and Deuflhard, Peter}, title = {Craniofacial Surgery Planning Based on Virtual Patient Models}, series = {it - Information Technology}, volume = {52}, journal = {it - Information Technology}, number = {5}, publisher = {Oldenbourg Verlagsgruppe}, doi = {10.1524/itit.2010.0600}, pages = {258 -- 263}, year = {2010}, language = {en} } @misc{WeiserErdmannSchenkletal.2017, author = {Weiser, Martin and Erdmann, Bodo and Schenkl, Sebastian and Muggenthaler, Holger and Hubig, Michael and Mall, Gita and Zachow, Stefan}, title = {Uncertainty in Temperature-Based Determination of Time of Death}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-63818}, year = {2017}, abstract = {Temperature-based estimation of time of death (ToD) can be per- formed either with the help of simple phenomenological models of corpse cooling or with detailed mechanistic (thermodynamic) heat transfer mod- els. The latter are much more complex, but allow a higher accuracy of ToD estimation as in principle all relevant cooling mechanisms can be taken into account. The potentially higher accuracy depends on the accuracy of tissue and environmental parameters as well as on the geometric resolution. We in- vestigate the impact of parameter variations and geometry representation on the estimated ToD based on a highly detailed 3D corpse model, that has been segmented and geometrically reconstructed from a computed to- mography (CT) data set, differentiating various organs and tissue types. From that we identify the most crucial parameters to measure or estimate, and obtain a local uncertainty quantifcation for the ToD.}, language = {en} } @article{WeiserErdmannSchenkletal., author = {Weiser, Martin and Erdmann, Bodo and Schenkl, Sebastian and Muggenthaler, Holger and Hubig, Michael and Mall, Gita and Zachow, Stefan}, title = {Uncertainty in Temperature-Based Determination of Time of Death}, series = {Heat and Mass Transfer}, volume = {54}, journal = {Heat and Mass Transfer}, number = {9}, publisher = {Springer}, doi = {10.1007/s00231-018-2324-4}, pages = {2815 -- 2826}, abstract = {Temperature-based estimation of time of death (ToD) can be per- formed either with the help of simple phenomenological models of corpse cooling or with detailed mechanistic (thermodynamic) heat transfer mod- els. The latter are much more complex, but allow a higher accuracy of ToD estimation as in principle all relevant cooling mechanisms can be taken into account. The potentially higher accuracy depends on the accuracy of tissue and environmental parameters as well as on the geometric resolution. We in- vestigate the impact of parameter variations and geometry representation on the estimated ToD based on a highly detailed 3D corpse model, that has been segmented and geometrically reconstructed from a computed to- mography (CT) data set, differentiating various organs and tissue types.}, language = {en} } @article{WagendorfNahlesVachetal., author = {Wagendorf, Oliver and Nahles, Susanne and Vach, Kirstin and Kernen, Florian and Zachow, Stefan and Heiland, Max and Fl{\"u}gge, Tabea}, title = {The impact of teeth and dental restorations on gray value distribution in cone-beam computer tomography - a pilot study}, series = {International Journal of Implant Dentistry}, volume = {9}, journal = {International Journal of Implant Dentistry}, number = {27}, doi = {10.1186/s40729-023-00493-z}, abstract = {Purpose: To investigate the influence of teeth and dental restorations on the facial skeleton's gray value distributions in cone-beam computed tomography (CBCT). Methods: Gray value selection for the upper and lower jaw segmentation was performed in 40 patients. In total, CBCT data of 20 maxillae and 20 mandibles, ten partial edentulous and ten fully edentulous in each jaw, respectively, were evaluated using two different gray value selection procedures: manual lower threshold selection and automated lower threshold selection. Two sample t tests, linear regression models, linear mixed models, and Pearson's correlation coefficients were computed to evaluate the influence of teeth, dental restorations, and threshold selection procedures on gray value distributions. Results: Manual threshold selection resulted in significantly different gray values in the fully and partially edentulous mandible. (p = 0.015, difference 123). In automated threshold selection, only tendencies to different gray values in fully edentulous compared to partially edentulous jaws were observed (difference: 58-75). Significantly different gray values were evaluated for threshold selection approaches, independent of the dental situation of the analyzed jaw. No significant correlation between the number of teeth and gray values was assessed, but a trend towards higher gray values in patients with more teeth was noted. Conclusions: Standard gray values derived from CT imaging do not apply for threshold-based bone segmentation in CBCT. Teeth influence gray values and segmentation results. Inaccurate bone segmentation may result in ill-fitting surgical guides produced on CBCT data and misinterpreting bone density, which is crucial for selecting surgical protocols.}, language = {en} } @article{vonTycowiczAmbellanMukhopadhyayetal., author = {von Tycowicz, Christoph and Ambellan, Felix and Mukhopadhyay, Anirban and Zachow, Stefan}, title = {An Efficient Riemannian Statistical Shape Model using Differential Coordinates}, series = {Medical Image Analysis}, volume = {43}, journal = {Medical Image Analysis}, number = {1}, doi = {10.1016/j.media.2017.09.004}, pages = {1 -- 9}, abstract = {We propose a novel Riemannian framework for statistical analysis of shapes that is able to account for the nonlinearity in shape variation. By adopting a physical perspective, we introduce a differential representation that puts the local geometric variability into focus. We model these differential coordinates as elements of a Lie group thereby endowing our shape space with a non-Euclidean structure. A key advantage of our framework is that statistics in a manifold shape space becomes numerically tractable improving performance by several orders of magnitude over state-of-the-art. We show that our Riemannian model is well suited for the identification of intra-population variability as well as inter-population differences. In particular, we demonstrate the superiority of the proposed model in experiments on specificity and generalization ability. We further derive a statistical shape descriptor that outperforms the standard Euclidean approach in terms of shape-based classification of morphological disorders.}, language = {en} } @inproceedings{vonBergDworzakKlinderetal.2011, author = {von Berg, Jens and Dworzak, Jalda and Klinder, Tobias and Manke, Dirk and Lamecker, Hans and Zachow, Stefan and Lorenz, Cristian}, title = {Temporal Subtraction of Chest Radiographs Compensating Pose Differences}, series = {SPIE Medical Imaging}, booktitle = {SPIE Medical Imaging}, year = {2011}, language = {en} } @misc{TycowiczAmbellanMukhopadhyayetal., author = {Tycowicz, Christoph von and Ambellan, Felix and Mukhopadhyay, Anirban and Zachow, Stefan}, title = {A Riemannian Statistical Shape Model using Differential Coordinates}, issn = {1438-0064}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-61175}, abstract = {We propose a novel Riemannian framework for statistical analysis of shapes that is able to account for the nonlinearity in shape variation. By adopting a physical perspective, we introduce a differential representation that puts the local geometric variability into focus. We model these differential coordinates as elements of a Lie group thereby endowing our shape space with a non-Euclidian structure. A key advantage of our framework is that statistics in a manifold shape space become numerically tractable improving performance by several orders of magnitude over state-of-the-art. We show that our Riemannian model is well suited for the identification of intra-population variability as well as inter-population differences. In particular, we demonstrate the superiority of the proposed model in experiments on specificity and generalization ability. We further derive a statistical shape descriptor that outperforms the standard Euclidian approach in terms of shape-based classification of morphological disorders.}, language = {en} } @article{TaylorPoepplauKoenigetal.2011, author = {Taylor, William R. and P{\"o}pplau, Berry M. and K{\"o}nig, Christian and Ehrig, Rainald and Zachow, Stefan and Duda, Georg and Heller, Markus O.}, title = {The medial-lateral force distribution in the ovine stifle joint during walking}, series = {Journal of Orthopaedic Research}, volume = {29}, journal = {Journal of Orthopaedic Research}, number = {4}, doi = {10.1002/jor.21254}, pages = {567 -- 571}, year = {2011}, language = {en} }