@phdthesis{Lamecker2008, author = {Lamecker, Hans}, title = {Variational and statistical shape modeling for 3D geometry reconstruction}, year = {2008}, abstract = {The reconstruction of geometric shapes plays an important role in many biomedical applications. One example is the patient-specific, computer-aided planning of complex interventions, which requires the generation of explicitly represented geometric models of anatomical structures from medical image data. Only solutions that require minimal interaction by medical personnel are likely to enter clinical routine. Another example is the planning of surgical corrections of deformities where the target shape is unknown. Surgeons are often forced to resort to subjective criteria. These applications still pose highly challenging reconstruction problems, which are addressed in this thesis. The fundamental hypothesis, pursued in this thesis, is that the problems can be solved by incorporating a-priori knowledge about shape and other application-specific characteristics. Here, we focus mainly on the aspect of geometric shape analysis. The basic idea is to capture the most essential variations of a certain class of geometric objects via statistical shape models, which model typical features contained in a given population, and restrict the outcome of a reconstruction algorithm (more or less) to the space spanned by such models. A fundamental prerequisite for performing statistical shape analysis on a set of different objects is the identification of corresponding points on their associated surfaces. This problem is particularly difficult to solve if the shapes stem from different individuals. The reason lies in the basic difficulty of defining suitable measures of similarity. In this thesis, we divide the correspondence problem into feature and non-feature matching. The feature part depends on the application, while the non-feature part can be characterized by a purely geometric description. We propose two different approaches. The first approach has proved useful in many applications. Yet, it suffers from some practical limitations and does not yield a measure of similarity. Our second, variational, approach is designed to overcome these limitations. In it, we propose to minimize an invariant stretching measure, constrained by previously computed features. An important property, which sets our method apart from previous work, is that it does not require the computation of a global surface parameterization.}, language = {en} } @misc{GuentherLameckerWeiser2011, author = {G{\"u}nther, Andreas and Lamecker, Hans and Weiser, Martin}, title = {Direct LDDMM of Discrete Currents with Adaptive Finite Elements}, doi = {10.1007/s11263-012-0599-3}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-13090}, number = {11-22}, year = {2011}, abstract = {We consider Large Deformation Diffeomorphic Metric Mapping of general \$m\$-currents. After stating an optimization algorithm in the function space of admissable morph generating velocity fields, two innovative aspects in this framework are presented and numerically investigated: First, we spatially discretize the velocity field with conforming adaptive finite elements and discuss advantages of this new approach. Second, we directly compute the temporal evolution of discrete \$m\$-current attributes.}, language = {en} } @misc{ZilskeLameckerZachow2007, 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}, year = {2007}, 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} } @inproceedings{LameckerLangeSeebass2003, author = {Lamecker, Hans and Lange, Thomas and Seebaß, Martin}, title = {Erzeugung statistischer 3D-Formmodelle zur Segmentierung medizinischer Bilddaten}, booktitle = {Proc. BVM 2003}, publisher = {Springer}, address = {Erlangen}, pages = {398 -- 403}, year = {2003}, language = {en} } @inproceedings{LangeLameckerSeebass2003, author = {Lange, Thomas and Lamecker, Hans and Seebaß, Martin}, title = {Ein Softwarepaket f{\"u}r die modellbasierte Segmentierung anatomischer Strukturen}, booktitle = {Proc. BVM 2003}, address = {Erlangen}, pages = {111 -- 116}, year = {2003}, language = {en} } @inproceedings{LameckerLangeSeebassetal.2003, author = {Lamecker, Hans and Lange, Thomas and Seebaß, Martin and Eulenstein, Sebastian and Westerhoff, Malte and Hege, Hans-Christian}, title = {Automatic Segmentation of the Liver for Preoperative Planning of Resections}, booktitle = {Proc. MMVR 2003}, publisher = {IOS press}, address = {Newport Beach, CA}, pages = {171 -- 173}, year = {2003}, language = {en} } @inproceedings{LangeLameckerEulenstein2002, author = {Lange, Thomas and Lamecker, Hans and Eulenstein, Sebastian}, title = {Automatische Segmentierung von Lebergewebe f{\"u}r die pr{\"a}operative Planung von Resektionen}, booktitle = {1. Jahrestagung der Deutschen Gesellschaft f{\"u}r Computer- Roboterassistierte Chirugie CURAC}, year = {2002}, language = {en} } @inproceedings{SeebassLameckerGellermannetal.2004, author = {Seebaß, Martin and Lamecker, Hans and Gellermann, Johanna and Wust, Peter}, title = {The impact of segmentation accuracy on treatment planning for regional hyperthermia}, booktitle = {Proceedings of the 9th International Congress on Hyperthermic Oncology}, year = {2004}, language = {en} } @inproceedings{EulensteinLangeHuenerbeinetal.2004, author = {Eulenstein, Sebastian and Lange, Thomas and H{\"u}nerbein, Michael and Schlag, Peter and Lamecker, Hans}, title = {Ultrasound based navigation system incorporating preoperative planning for liver surgery}, volume = {1268}, booktitle = {Proceedings CARS}, publisher = {Elsevier}, doi = {10.1016/j.ics.2004.03.121 target}, pages = {758 -- 763}, year = {2004}, language = {en} } @inproceedings{LangeTunnLameckeretal.2004, author = {Lange, Thomas and Tunn, Per-Ulf and Lamecker, Hans and Scheinemann, Peter and Eulenstein, Sebastian and Schlag, Peter-Michael}, title = {Computerunterst{\"u}tzte Prothesenkonstruktion mittels statistischem Formmodell bei Beckenresektion}, booktitle = {Proceedings BVM, Informatik aktuell}, editor = {Tolxdorff, Thomas}, publisher = {Springer}, pages = {30 -- 34}, year = {2004}, language = {en} }