@article{MaierDesernoHandelsetal., author = {Maier, Andreas and Deserno, Thomas M. and Handels, Heinz and Maier-Hein, Klaus H. and Palm, Christoph and Tolxdorff, Thomas}, title = {IJCARS: BVM 2021 special issue}, series = {International Journal of Computer Assisted Radiology and Surgery}, volume = {16}, journal = {International Journal of Computer Assisted Radiology and Surgery}, publisher = {Springer}, doi = {10.1007/s11548-021-02534-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-21666}, pages = {2067 -- 2068}, abstract = {The German workshop on medical image computing (BVM) has been held in different locations in Germany for more than 20 years. In terms of content, BVM focused on the computer-aided analysis of medical image data with a wide range of applications, e.g. in the area of imaging, diagnostics, operation planning, computer-aided intervention and visualization. During this time, there have been remarkable methodological developments and upheavals, on which the BVM community has worked intensively. The area of machine learning should be emphasized, which has led to significant improvements, especially for tasks of classification and segmentation, but increasingly also in image formation and registration. As a result, work in connection with deep learning now dominates the BVM. These developments have also contributed to the establishment of medical image processing at the interface between computer science and medicine as one of the key technologies for the digitization of the health system. In addition to the presentation of current research results, a central aspect of the BVM is primarily the promotion of young scientists from the diverse BVM community, covering not only Germany but also Austria, Switzerland, The Netherland and other European neighbors. The conference serves primarily doctoral students and postdocs, but also students with excellent bachelor and master theses as a platform to present their work, to enter into professional discourse with the community, and to establish networks with specialist colleagues. Despite the many conferences and congresses that are also relevant for medical image processing, the BVM has therefore lost none of its importance and attractiveness and has retained its permanent place in the annual conference rhythm. Building on this foundation, there are some innovations and changes this year. The BVM 2021 was organized for the first time at the Ostbayerische Technische Hochschule Regensburg (OTH Regensburg, a technical university of applied sciences). After Aachen, Berlin, Erlangen, Freiburg, Hamburg, Heidelberg, Leipzig, L{\"u}beck, and Munich, Regensburg is not just a new venue. OTH Regensburg is the first representative of the universities of applied sciences (HAW) to organize the conference, which differs to universities, university hospitals, or research centers like Fraunhofer or Helmholtz. This also considers the further development of the research landscape in Germany, where HAWs increasingly contribute to applied research in addition to their focus on teaching. This development is also reflected in the contributions submitted to the BVM in recent years. At BVM 2021, which was held in a virtual format for the first time due to the Corona pandemic, an attractive and high-quality program was offered. Fortunately, the number of submissions increased significantly. Out of 97 submissions, 26 presentations, 51 posters and 5 software demonstrations were accepted via an anonymized reviewing process with three reviews each. The three best works have been awarded BVM prizes, selected by a separate committee. Based on these high-quality submissions, we are able to present another special issue in the International Journal of Computer Assisted Radiology and Surgery (IJCARS). Out of the 97 submissions, the ones with the highest scores have been invited to submit an extended version of their paper to be presented in IJCARS. As a result, we are now able to present this special issue with seven excellent articles. Many submissions focus on machine learning in a medical context.}, subject = {Bildgebendes Verfahren}, language = {en} } @article{SchulzePalmKerschbaumetal., author = {Schulze, Elke and Palm, Christoph and Kerschbaum, Maximilian and Seidel, Roman and Lehmann, Lars and Koller, Michael and Pfingsten, Andrea}, title = {KI-gest{\"u}tzte Untersuchung in der nicht-operativen Versorgung symptomgebender Erkrankungen des Kniegelenks - ein multiprofessionelles Konzept (KINEESIO)}, series = {MSK - Muskuloskelettale Physiotherapie}, volume = {28}, journal = {MSK - Muskuloskelettale Physiotherapie}, number = {5}, publisher = {Thieme}, issn = {2701-6986}, doi = {10.1055/a-2402-9982}, pages = {312 -- 321}, abstract = {Beschwerdebilder am Kniegelenk aufgrund muskuloskelettaler degenerativer oder verletzungsbedingter Erkrankungen sind h{\"a}ufig, nehmen im Alter zu und sind mit der steigenden Inanspruchnahme {\"a}rztlicher und therapeutischer Behandlungsmaßnahmen verbunden. Einer erfolgreichen Therapie gehen oft notwendige zeit- und ressourcenaufwendige Untersuchungen zur Erkennung und Differenzierung der patient*innenspezifischen Problematik voraus. Im Zusammenhang mit der nicht-operativen Versorgung des Kniegelenks hat ein sektor{\"u}bergreifendes multiprofessionelles Forschungsteam ein Konzept entwickelt, um k{\"u}nstliche neuronale Netze so zu trainieren, dass sie bei der {\"a}rztlichen und physiotherapeutischen Untersuchung unterst{\"u}tzend Einsatz finden k{\"o}nnen. Denn gerade in der Erfassung und Auswertung umfassender Datenmengen liegen große Potenziale in der K{\"u}nstlichen Intelligenz (KI) im Gesundheitswesen. Das Projekt KINEESIO trainiert und testet KI-gest{\"u}tzte Screening- Tools zur Untersuchung von Patient*innen mit Kniegelenkerkrankungen. Diese unterst{\"u}tzen die Abl{\"a}ufe zwischen Leistungserbringern und Patient*innen, tragen zu einer verbesserten Differenzierung individueller Beschwerdebilder bei und dienen Entscheidungsprozessen f{\"u}r eine ad{\"a}quate Versorgung. Dadurch sollen Ressourcen im Gesundheitswesen geschont und eine qualitativ hochwertige Therapie ausreichend erm{\"o}glicht werden.}, language = {de} } @article{HartmannWeihererSchiltzetal., author = {Hartmann, Robin and Weiherer, Maximilian and Schiltz, Daniel and Seitz, Stephan and Lotter, Luisa and Anker, Alexandra and Palm, Christoph and Prantl, Lukas and Br{\´e}bant, Vanessa}, title = {A Novel Method of Outcome Assessment in Breast Reconstruction Surgery: Comparison of Autologous and Alloplastic Techniques Using Three-Dimensional Surface Imaging}, series = {Aesthetic Plastic Surgery}, volume = {44}, journal = {Aesthetic Plastic Surgery}, publisher = {Springer}, address = {Heidelberg}, doi = {10.1007/s00266-020-01749-4}, pages = {1980 -- 1987}, abstract = {Background Breast reconstruction is an important coping tool for patients undergoing a mastectomy. There are numerous surgical techniques in breast reconstruction surgery (BRS). Regardless of the technique used, creating a symmetric outcome is crucial for patients and plastic surgeons. Three-dimensional surface imaging enables surgeons and patients to assess the outcome's symmetry in BRS. To discriminate between autologous and alloplastic techniques, we analyzed both techniques using objective optical computerized symmetry analysis. Software was developed that enables clinicians to assess optical breast symmetry using three-dimensional surface imaging. Methods Twenty-seven patients who had undergone autologous (n = 12) or alloplastic (n = 15) BRS received three-dimensional surface imaging. Anthropomorphic data were collected digitally using semiautomatic measurements and automatic measurements. Automatic measurements were taken using the newly developed software. To quantify symmetry, a Symmetry Index is proposed. Results Statistical analysis revealed that there is no dif- ference in the outcome symmetry between the two groups (t test for independent samples; p = 0.48, two-tailed). Conclusion This study's findings provide a foundation for qualitative symmetry assessment in BRS using automatized digital anthropometry. In the present trial, no difference in the outcomes' optical symmetry was detected between autologous and alloplastic approaches.}, subject = {Mammoplastik}, language = {en} } @article{HartmannWeihererSchiltzetal., author = {Hartmann, Robin and Weiherer, Maximilian and Schiltz, Daniel and Baringer, Magnus and Noisser, Vivien and H{\"o}sl, Vanessa and Eigenberger, Andreas and Seitz, Stefan and Palm, Christoph and Prantl, Lukas and Br{\´e}bant, Vanessa}, title = {New aspects in digital breast assessment: further refinement of a method for automated digital anthropometry}, series = {Archives of Gynecology and Obstetrics}, volume = {303}, journal = {Archives of Gynecology and Obstetrics}, publisher = {Springer Nature}, address = {Heidelberg}, issn = {1432-0711}, doi = {10.1007/s00404-020-05862-2}, pages = {721 -- 728}, abstract = {Purpose: In this trial, we used a previously developed prototype software to assess aesthetic results after reconstructive surgery for congenital breast asymmetry using automated anthropometry. To prove the consensus between the manual and automatic digital measurements, we evaluated the software by comparing the manual and automatic measurements of 46 breasts. Methods: Twenty-three patients who underwent reconstructive surgery for congenital breast asymmetry at our institution were examined and underwent 3D surface imaging. Per patient, 14 manual and 14 computer-based anthropometric measurements were obtained according to a standardized protocol. Manual and automatic measurements, as well as the previously proposed Symmetry Index (SI), were compared. Results: The Wilcoxon signed-rank test revealed no significant differences in six of the seven measurements between the automatic and manual assessments. The SI showed robust agreement between the automatic and manual methods. Conclusion: The present trial validates our method for digital anthropometry. Despite the discrepancy in one measurement, all remaining measurements, including the SI, showed high agreement between the manual and automatic methods. The proposed data bring us one step closer to the long-term goal of establishing robust instruments to evaluate the results of breast surgery.}, language = {en} } @inproceedings{MendelSouzaJrRauberetal., author = {Mendel, Robert and Souza Jr., Luis Antonio de and Rauber, David and Papa, Jo{\~a}o Paulo and Palm, Christoph}, title = {Semi-supervised Segmentation Based on Error-Correcting Supervision}, series = {Computer vision - ECCV 2020: 16th European conference, Glasgow, UK, August 23-28, 2020, Proceedings, Part XXIX}, booktitle = {Computer vision - ECCV 2020: 16th European conference, Glasgow, UK, August 23-28, 2020, Proceedings, Part XXIX}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-58525-9}, doi = {10.1007/978-3-030-58526-6_9}, pages = {141 -- 157}, abstract = {Pixel-level classification is an essential part of computer vision. For learning from labeled data, many powerful deep learning models have been developed recently. In this work, we augment such supervised segmentation models by allowing them to learn from unlabeled data. Our semi-supervised approach, termed Error-Correcting Supervision, leverages a collaborative strategy. Apart from the supervised training on the labeled data, the segmentation network is judged by an additional network. The secondary correction network learns on the labeled data to optimally spot correct predictions, as well as to amend incorrect ones. As auxiliary regularization term, the corrector directly influences the supervised training of the segmentation network. On unlabeled data, the output of the correction network is essential to create a proxy for the unknown truth. The corrector's output is combined with the segmentation network's prediction to form the new target. We propose a loss function that incorporates both the pseudo-labels as well as the predictive certainty of the correction network. Our approach can easily be added to supervised segmentation models. We show consistent improvements over a supervised baseline on experiments on both the Pascal VOC 2012 and the Cityscapes datasets with varying amounts of labeled data.}, subject = {Semi-Supervised Learning}, language = {en} } @inproceedings{PalmSchollLehmannetal., author = {Palm, Christoph and Scholl, Ingrid and Lehmann, Thomas M. and Spitzer, Klaus}, title = {Trennung von diffuser und spiegelnder Reflexion in Farbbildern des Larynx zur Untersuchung von Farb- und Formmerkmalen der Stimmlippen}, series = {Bildverarbeitung f{\"u}r die Medizin. Algorithmen, Systeme, Anwendungen. Proceedings des Aachener Workshops am 8. und 9. November 1996}, booktitle = {Bildverarbeitung f{\"u}r die Medizin. Algorithmen, Systeme, Anwendungen. Proceedings des Aachener Workshops am 8. und 9. November 1996}, editor = {Lehmann, Thomas M. and Scholl, Ingrid and Spitzer, Klaus}, publisher = {Verlag der Augustinus-Buchhandlung}, address = {Aachen}, pages = {229 -- 234}, abstract = {Zur diagnostischen Unterst{\"u}tzung bei der Befundung laryngealer Erkrankungen soll eine Farb- und Formanalyse der Stimmlippen durchgef{\"u}hrt werden. In diesem Beitrag wird ein Verfahren zur Trennung der spiegelnden und diffusen Reflexionsanteile in Farbbildern des Larynx vorgestellt. Die Farbe der diffusen Komponente entspricht dabei der beleuchtungsunabh{\"a}ngigen Objektfarbe, w{\"a}hrend deren Wichtungsfaktoren als Eingabe f{\"u}r Shape-from-Shading-Verfahren zur Oberfl{\"a}chenrekonstruktion dienen.}, subject = {Laryngoskopie}, language = {de} } @inproceedings{HassanIlgnerPalmetal., author = {Hassan, H. and Ilgner, Justus F. R. and Palm, Christoph and Lehmann, Thomas M. and Spitzer, Klaus and Westhofen, Martin}, title = {Objective Judgement of Endoscopic Laryngeal Images}, series = {Advances in Quantitative Laryngoscopy, Voice and Speech Research, Proceedings of the 3rd International Workshop, RWTH Aachen}, booktitle = {Advances in Quantitative Laryngoscopy, Voice and Speech Research, Proceedings of the 3rd International Workshop, RWTH Aachen}, editor = {Lehmann, Thomas M. and Spitzer, Klaus and Tolxdorff, Thomas}, pages = {135 -- 142}, abstract = {Video Documentation of endoscopic findings simplifies diagnostic counseling of the patient and aids pre-operative discussion among the medical team. Judgment of such images is still subjective and can not give a quantitative evaluation of the disease process regarding diagnosis or response to treatment. Modern treatment of early laryngeal cancer with laserablation requires intensive follow up and frequent direct laryngoscopy under general anesthesia with blind biopsies to detect any tumor residual or recurrence. Inflammatory conditions of the larynx are frequently confused with other causes of dysphonia. Mapping anddigital analysis of the documented image will suggest the tumor site and avoids undue blind biopsies under anesthesia. However, varying illumination results in different colors reflected from the same object. To achieve quantitative analysis, color constancy has to be assured. Inthis paper, the environment is presented which allow the objective judgment of larngoscopies.}, language = {en} } @inproceedings{SchollPalmSovakaretal., author = {Scholl, Ingrid and Palm, Christoph and Sovakar, Abhijit and Lehmann, Thomas M. and Spitzer, Klaus}, title = {Quantitative Analyse der Stimmlippen}, series = {5. Workshop Digitale Bildverarbeitung in der Medizin, Universit{\"a}t Freiburg, 10.-11. M{\"a}rz 1997}, booktitle = {5. Workshop Digitale Bildverarbeitung in der Medizin, Universit{\"a}t Freiburg, 10.-11. M{\"a}rz 1997}, editor = {Arnolds, B. and Mueller, H. and Saupe, D. and Tolxdorff, Thomas}, pages = {81 -- 86}, language = {de} } @misc{KreftingZaunsederSaeringetal., author = {Krefting, Dagmar and Zaunseder, Sebastian and S{\"a}ring, Dennis and Wittenberg, Thomas and Palm, Christoph and Schiecke, Karin and Krenkel, Lars and Hennemuth, Anja and Schnell, Susanne and Spicher, Nicolai}, title = {Blutdruck, H{\"a}modynamik und Gef{\"a}ßzustand: Innovative Erfassung und Bewertung - Schwerpunkt bildbasierte Verfahren}, series = {66. Jahrestagung der Deutschen Gesellschaft f{\"u}r Medizinische Informatik, Biometrie und Epidemiologie e. V. (GMDS), 12. Jahreskongress der Technologie- und Methodenplattform f{\"u}r die vernetzte medizinische Forschung e. V. (TMF), 26. - 30.09.2021, online}, journal = {66. Jahrestagung der Deutschen Gesellschaft f{\"u}r Medizinische Informatik, Biometrie und Epidemiologie e. V. (GMDS), 12. Jahreskongress der Technologie- und Methodenplattform f{\"u}r die vernetzte medizinische Forschung e. V. (TMF), 26. - 30.09.2021, online}, doi = {10.3205/21gmds016}, url = {http://nbn-resolving.de/urn:nbn:de:0183-21gmds0167}, abstract = {Einleitung: Blutdruck gilt als sogenannter Vitalparameter als einer der grundlegenden Indikatoren f{\"u}r den Gesundheitszustand einer Person. Sowohl zu niedriger als auch zu hoher Blutdruck kann lebensbedrohend sein, letzerer ist dar{\"u}ber hinaus ein Risikofaktor insbesondere f{\"u}r Herz-Kreislauferkrankungen, die trotz wichtiger Fortschritte in der Behandlung immer noch die h{\"a}ufigste Todesursache in Deutschland darstellen. Die H{\"a}modynamik, also die raumzeitliche Dynamik des Blutflusses, und der Gef{\"a}ßzustand sind eng verbunden mit dem Blutdruck und ebenfalls von hoher klinischer Relevanz, u.a. zur Identifikation von Durchblutungsst{\"o}rungen und ung{\"u}nstigen Druckverteilungen der Gef{\"a}ßwand. Innovationen in der Messtechnik als auch in der Datenanalyse bieten heute neue M{\"o}glichkeiten der Erfassung und Bewertung von Blutdruck, H{\"a}modynamik und Gef{\"a}ßzustand [1], [2], [3], [4]. Methodik: In einer gemeinsamen Workshopserie der AG Medizinische Bild- und Signalverarbeitung der GMDS und des Fachausschusses Biosignale der DGBMT werden wir neue Ans{\"a}tze und L{\"o}sungen f{\"u}r Mess- und Analyseverfahren zu Blutdruck und -fluss sowie zum Gef{\"a}ßzustand vorstellen und diskutieren. Dabei stehen im ersten Workshop auf der GMDS Jahrestagung Bildbasierte Verfahren im Zentrum, w{\"a}hrend der zweite Workshop auf der DGBMT Jahrestagung den Fokus auf Biosignalbasierten Verfahren legt. Es werden aktuelle Forschungsergebnisse vorgestellt und diskutiert. Es sind jeweils mehrere Vortr{\"a}ge geplant mit ausreichend Zeit zur Diskussion. Folgende Vortr{\"a}ge sind geplant (Arbeitstitel): Sebastian Zaunseder: Videobasierte Erfassung des Blutdrucks Anja Hennemuth: A Visualization Toolkit for the Analysis of Aortic Anatomy and Pressure Distribution Lars Krenkel: Numerische Analyse der Rupturwahrscheinlichkeit zerebraler Aneurysmata Susanne Schnell: Messung des Blutflusses und h{\"a}modynamischer Parameter mit 4D flow MRI: M{\"o}glichkeiten und Herausforderungen Ergebnisse: Ziel des Workshops ist die Identifikation von innovativen Ans{\"a}tzen und neuen Methoden zur qualitativen und quantitativen Bestimmung von h{\"a}modynamischen Parametern sowie deren kritische Bewertung durch die Community f{\"u}r die Eignung in der klinischen Entscheidungsunterst{\"u}tzung. Diskussion: Der Workshop leistet inhaltlich einen Beitrag zu zentralen Aspekten f{\"u}r die Herz-Kreislauf-Medizin. Er bringt dabei Expertise aus verschiedenen Bereichen zusammen und schl{\"a}gt die Br{\"u}cke zwischen Kardiologie, Medizininformatik und Medizintechnik. Schlussfolgerung: Innovative Technologien aus Medizintechnik und Informatik erm{\"o}glichen zunehmend einfache und raumzeitlich aufgel{\"o}ste Erfassung und Bewertung wichtiger Informationen zur Unterst{\"u}tzung von Diagnose und Therapieverfolgung. [1] Zaunseder S, Trumpp A, Wedekind D, Malberg H. Cardiovascular assessment by imaging photoplethysmography - a review. Biomed Tech (Berl). 2018 Oct 25;63(5):617-34. [2] Huellebrand M, Messroghli D, Tautz L, Kuehne T, Hennemuth A. An extensible software platform for interdisciplinary cardiovascular imaging research. Comput Methods Programs Biomed. 2020 Feb;184:105277. [3] Schmitter S, Adriany G, Waks M, Moeller S, Aristova M, Vali A, et al. Bilateral Multiband 4D Flow MRI of the Carotid Arteries at 7T. Magn Reson Med. 2020 Oct;84(4):1947-60. [4] Birkenmaier C, and Krenkel, L. Flow in Artificial Lungs. In: New Results in Numerical and Experimental Fluid Mechanics XIII. Contributions to the 22nd STAB/DGLR Symposium. Springer; 2021.}, subject = {Blutdruck}, language = {de} } @article{GrassmannMengelkampBrandletal., author = {Graßmann, Felix and Mengelkamp, Judith and Brandl, Caroline and Harsch, Sebastian and Zimmermann, Martina E. and Linkohr, Birgit and Peters, Annette and Heid, Iris M. and Palm, Christoph and Weber, Bernhard H. F.}, title = {A Deep Learning Algorithm for Prediction of Age-Related Eye Disease Study Severity Scale for Age-Related Macular Degeneration from Color Fundus Photography}, series = {Ophtalmology}, volume = {125}, journal = {Ophtalmology}, number = {9}, publisher = {Elsevier}, doi = {10.1016/j.ophtha.2018.02.037}, pages = {1410 -- 1420}, abstract = {Purpose Age-related macular degeneration (AMD) is a common threat to vision. While classification of disease stages is critical to understanding disease risk and progression, several systems based on color fundus photographs are known. Most of these require in-depth and time-consuming analysis of fundus images. Herein, we present an automated computer-based classification algorithm. Design Algorithm development for AMD classification based on a large collection of color fundus images. Validation is performed on a cross-sectional, population-based study. Participants. We included 120 656 manually graded color fundus images from 3654 Age-Related Eye Disease Study (AREDS) participants. AREDS participants were >55 years of age, and non-AMD sight-threatening diseases were excluded at recruitment. In addition, performance of our algorithm was evaluated in 5555 fundus images from the population-based Kooperative Gesundheitsforschung in der Region Augsburg (KORA; Cooperative Health Research in the Region of Augsburg) study. Methods. We defined 13 classes (9 AREDS steps, 3 late AMD stages, and 1 for ungradable images) and trained several convolution deep learning architectures. An ensemble of network architectures improved prediction accuracy. An independent dataset was used to evaluate the performance of our algorithm in a population-based study. Main Outcome Measures. κ Statistics and accuracy to evaluate the concordance between predicted and expert human grader classification. Results. A network ensemble of 6 different neural net architectures predicted the 13 classes in the AREDS test set with a quadratic weighted κ of 92\% (95\% confidence interval, 89\%-92\%) and an overall accuracy of 63.3\%. In the independent KORA dataset, images wrongly classified as AMD were mainly the result of a macular reflex observed in young individuals. By restricting the KORA analysis to individuals >55 years of age and prior exclusion of other retinopathies, the weighted and unweighted κ increased to 50\% and 63\%, respectively. Importantly, the algorithm detected 84.2\% of all fundus images with definite signs of early or late AMD. Overall, 94.3\% of healthy fundus images were classified correctly. Conclusions Our deep learning algoritm revealed a weighted κ outperforming human graders in the AREDS study and is suitable to classify AMD fundus images in other datasets using individuals >55 years of age.}, subject = {Senile Makuladegeneration}, language = {en} } @article{HartmannWeihererNieberleetal., author = {Hartmann, Robin and Weiherer, Maximilian and Nieberle, Felix and Palm, Christoph and Br{\´e}bant, Vanessa and Prantl, Lukas and Lamby, Philipp and Reichert, Torsten E. and Taxis, J{\"u}rgen and Ettl, Tobias}, title = {Evaluating smartphone-based 3D imaging techniques for clinical application in oral and maxillofacial surgery: A comparative study with the vectra M5}, series = {Oral and Maxillofacial Surgery}, volume = {29}, journal = {Oral and Maxillofacial Surgery}, publisher = {Springer Nature}, doi = {10.1007/s10006-024-01322-2}, pages = {17}, abstract = {PURPOSE This study aimed to clarify the applicability of smartphone-based three-dimensional (3D) surface imaging for clinical use in oral and maxillofacial surgery, comparing two smartphone-based approaches to the gold standard. METHODS Facial surface models (SMs) were generated for 30 volunteers (15 men, 15 women) using the Vectra M5 (Canfield Scientific, USA), the TrueDepth camera of the iPhone 14 Pro (Apple Inc., USA), and the iPhone 14 Pro with photogrammetry. Smartphone-based SMs were superimposed onto Vectra-based SMs. Linear measurements and volumetric evaluations were performed to evaluate surface-to-surface deviation. To assess inter-observer reliability, all measurements were performed independently by a second observer. Statistical analyses included Bland-Altman analyses, the Wilcoxon signed-rank test for paired samples, and Intraclass correlation coefficients. RESULTS Photogrammetry-based SMs exhibited an overall landmark-to-landmark deviation of M = 0.8 mm (SD =  ± 0.58 mm, n = 450), while TrueDepth-based SMs displayed a deviation of M = 1.1 mm (SD =  ± 0.72 mm, n = 450). The mean volumetric difference for photogrammetry-based SMs was M = 1.8 cc (SD =  ± 2.12 cc, n = 90), and M = 3.1 cc (SD =  ± 2.64 cc, n = 90) for TrueDepth-based SMs. When comparing the two approaches, most landmark-to-landmark measurements demonstrated 95\% Bland-Altman limits of agreement (LoA) of ≤ 2 mm. Volumetric measurements revealed LoA > 2 cc. Photogrammetry-based measurements demonstrated higher inter-observer reliability for overall landmark-to-landmark deviation. CONCLUSION Both approaches for smartphone-based 3D surface imaging exhibit potential in capturing the face. Photogrammetry-based SMs demonstrated superior alignment and volumetric accuracy with Vectra-based SMs than TrueDepth-based SMs.}, language = {en} } @article{MaierPerretSimonetal., author = {Maier, Johannes and Perret, Jerome and Simon, Martina and Schmitt-R{\"u}th, Stephanie and Wittenberg, Thomas and Palm, Christoph}, title = {Force-feedback assisted and virtual fixtures based K-wire drilling simulation}, series = {Computers in Biology and Medicine}, volume = {114}, journal = {Computers in Biology and Medicine}, publisher = {Elsevier}, doi = {10.1016/j.compbiomed.2019.103473}, pages = {1 -- 10}, abstract = {One common method to fix fractures of the human hand after an accident is an osteosynthesis with Kirschner wires (K-wires) to stabilize the bone fragments. The insertion of K-wires is a delicate minimally invasive surgery, because surgeons operate almost without a sight. Since realistic training methods are time consuming, costly and insufficient, a virtual-reality (VR) based training system for the placement of K-wires was developed. As part of this, the current work deals with the real-time bone drilling simulation using a haptic force-feedback device. To simulate the drilling, we introduce a virtual fixture based force-feedback drilling approach. By decomposition of the drilling task into individual phases, each phase can be handled individually to perfectly control the drilling procedure. We report about the related finite state machine (FSM), describe the haptic feedback of each state and explain, how to avoid jerking of the haptic force-feedback during state transition. The usage of the virtual fixture approach results in a good haptic performance and a stable drilling behavior. This was confirmed by 26 expert surgeons, who evaluated the virtual drilling on the simulator and rated it as very realistic. To make the system even more convincing, we determined real drilling feed rates through experimental pig bone drilling and transferred them to our system. Due to a constant simulation thread we can guarantee a precise drilling motion. Virtual fixtures based force-feedback calculation is able to simulate force-feedback assisted bone drilling with high quality and, thus, will have a great potential in developing medical applications.}, subject = {Handchirurgie}, language = {en} } @inproceedings{SouzaPachecodeAngeloetal., author = {Souza, Luis A. and Pacheco, Andr{\´e} G.C. and de Angelo, Gabriel G. and Oliveira-Santos, Thiago and Palm, Christoph and Papa, Jo{\~a}o Paulo}, title = {LiwTERM: A Lightweight Transformer-Based Model for Dermatological Multimodal Lesion Detection}, series = {2024 37th SIBGRAPI Conference on Graphics, Patterns and Images (SIBGRAPI), Manaus, Brazil, 9/30/2024 - 10/3/2024}, booktitle = {2024 37th SIBGRAPI Conference on Graphics, Patterns and Images (SIBGRAPI), Manaus, Brazil, 9/30/2024 - 10/3/2024}, publisher = {IEEE}, isbn = {979-8-3503-7603-6}, doi = {10.1109/SIBGRAPI62404.2024.10716324}, pages = {1 -- 6}, abstract = {Skin cancer is the most common type of cancer in the world, accounting for approximately 30\% of all diagnosed tumors. Early diagnosis reduces mortality rates and prevents disfiguring effects in different body regions. In recent years, machine learning techniques, particularly deep learning, have shown promising results in this task, presenting studies that have demonstrated that combining a patient's clinical information with images of the lesion is crucial for improving the classification of skin lesions. Despite that, meaningful use of clinical information with multiple images is mandatory, requiring further investigation. Thus, this project aims to contribute to developing multimodal machine learning-based models to cope with the skin lesion classification task employing a lightweight transformer model. As a main hypothesis, models can take multiple images from different sources as input, along with clinical information from the patient's history, leading to a more reliable diagnosis. Our model deals with the not-trivial task of combining images and clinical information (from anamneses) concerning the skin lesions in a lightweight transformer architecture that does not demand high computation resources but still presents competitive classification results.}, language = {en} } @inproceedings{SouzaJrPassosMendeletal., author = {Souza Jr., Luis Antonio de and Passos, Leandro A. and Mendel, Robert and Ebigbo, Alanna and Probst, Andreas and Messmann, Helmut and Palm, Christoph and Papa, Jo{\~a}o Paulo}, title = {Fine-tuning Generative Adversarial Networks using Metaheuristics}, series = {Bildverarbeitung f{\"u}r die Medizin 2021. Proceedings, German Workshop on Medical Image Computing, Regensburg, March 7-9, 2021}, booktitle = {Bildverarbeitung f{\"u}r die Medizin 2021. Proceedings, German Workshop on Medical Image Computing, Regensburg, March 7-9, 2021}, publisher = {Springer Vieweg}, address = {Wiesbaden}, isbn = {978-3-658-33197-9}, doi = {10.1007/978-3-658-33198-6_50}, pages = {205 -- 210}, abstract = {Barrett's esophagus denotes a disorder in the digestive system that affects the esophagus' mucosal cells, causing reflux, and showing potential convergence to esophageal adenocarcinoma if not treated in initial stages. Thus, fast and reliable computer-aided diagnosis becomes considerably welcome. Nevertheless, such approaches usually suffer from imbalanced datasets, which can be addressed through Generative Adversarial Networks (GANs). Such techniques generate realistic images based on observed samples, even though at the cost of a proper selection of its hyperparameters. Many works employed a class of nature-inspired algorithms called metaheuristics to tackle the problem considering distinct deep learning approaches. Therefore, this paper's main contribution is to introduce metaheuristic techniques to fine-tune GANs in the context of Barrett's esophagus identification, as well as to investigate the feasibility of generating high-quality synthetic images for early-cancer assisted identification.}, subject = {Endoskopie}, language = {en} } @inproceedings{SzaloZehnerPalm, author = {Szalo, Alexander Eduard and Zehner, Alexander and Palm, Christoph}, title = {GraphMIC: Medizinische Bildverarbeitung in der Lehre}, series = {Bildverarbeitung f{\"u}r die Medizin 2015; Algorithmen - Systeme - Anwendungen; Proceedings des Workshops vom 15. bis 17. M{\"a}rz 2015 in L{\"u}beck}, booktitle = {Bildverarbeitung f{\"u}r die Medizin 2015; Algorithmen - Systeme - Anwendungen; Proceedings des Workshops vom 15. bis 17. M{\"a}rz 2015 in L{\"u}beck}, publisher = {Springer}, address = {Berlin}, doi = {10.1007/978-3-662-46224-9_68}, pages = {395 -- 400}, abstract = {Die Lehre der medizinischen Bildverarbeitung vermittelt Kenntnisse mit einem breiten Methodenspektrum. Neben den Grundlagen der Verfahren soll ein Gef{\"u}hl f{\"u}r eine geeignete Ausf{\"u}hrungsreihenfolge und ihrer Wirkung auf medizinische Bilddaten entwickelt werden. Die Komplexit{\"a}t der Methoden erfordert vertiefte Programmierkenntnisse, sodass bereits einfache Operationen mit großem Programmieraufwand verbunden sind. Die Software GraphMIC stellt Bildverarbeitungsoperationen in Form interaktiver Knoten zur Verf{\"u}gung und erlaubt das Arrangieren, Parametrisieren und Ausf{\"u}hren komplexer Verarbeitungssequenzen in einem Graphen. Durch den Fokus auf das Design einer Pipeline, weg von sprach- und frameworkspezifischen Implementierungsdetails, lassen sich grundlegende Prinzipien der Bildverarbeitung anschaulich erlernen. In diesem Beitrag stellen wir die visuelle Programmierung mit GraphMIC der nativen Implementierung {\"a}quivalenter Funktionen gegen{\"u}ber. Die in C++ entwickelte Applikation basiert auf Qt, ITK, OpenCV, VTK und MITK.}, subject = {Bildverarbeitung}, language = {de} }