The Experts below are selected from a list of 42987 Experts worldwide ranked by ideXlab platform
Ajit P Yoganathan - One of the best experts on this subject based on the ideXlab platform.
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the first cohort of prospective fontan Surgical Planning patients with follow up data how accurate is Surgical Planning
The Journal of Thoracic and Cardiovascular Surgery, 2019Co-Authors: Phillip M Trusty, Kirk R Kanter, Zhenglun Alan Wei, Timothy C Slesnick, Thomas L Spray, Mark A Fogel, Ajit P YoganathanAbstract:Abstract Objective Fontan Surgical Planning is an image-based, collaborative effort, which is hypothesized to result in improved patient outcomes. A common motivation for Fontan Surgical Planning is the progression (or concern for progression) of pulmonary arteriovenous malformations. The purpose of this study was to evaluate the accuracy of Surgical Planning predictions, specifically hepatic flow distribution (HFD), a known factor in pulmonary arteriovenous malformation progression, and identify methodological improvements needed to increase prediction accuracy. Methods Twelve single-ventricle patients who were enrolled in a Surgical Planning protocol for Fontan surgery with pre- and postoperative cardiac imaging were included in this study. Computational fluid dynamics were used to compare HFD in the Surgical Planning prediction and actual postoperative conditions. Results Overall, HFD prediction error was 17 ± 13%. This error was similar between surgery types (15 ± 18% and 18 ± 10% for revisions vs Fontan completions respectively; P = .73), but was significantly lower (6 ± 7%; P = .05) for hepatic to azygous shunts. Y-grafts and extracardiac conduits showed a strong correlation between prediction error and discrepancies in graft insertion points (r = 0.99; P Conclusions Although Fontan Surgical Planning can offer accurate HFD predictions for specific graft types, methodological improvements are needed to increase overall accuracy. Specifically, improving postoperative anatomy prediction was shown to be an important target for future work. Future efforts and refinements to the Surgical Planning process will benefit from an improved understanding of the current state and will rely heavily on increased follow-up data.
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fontan Surgical Planning previous accomplishments current challenges and future directions
Journal of Cardiovascular Translational Research, 2018Co-Authors: Phillip M Trusty, Kirk R Kanter, Jarek Rossignac, Zhenglun Alan Wei, Timothy C Slesnick, Mark A Fogel, Ajit P YoganathanAbstract:The ultimate goal of Fontan Surgical Planning is to provide additional insights into the clinical decision-making process. In its current state, Surgical Planning offers an accurate hemodynamic assessment of the pre-operative condition, provides anatomical constraints for potential Surgical options, and produces decent post-operative predictions if boundary conditions are similar enough between the pre-operative and post-operative states. Moving forward, validation with post-operative data is a necessary step in order to assess the accuracy of Surgical Planning and determine which methodological improvements are needed. Future efforts to automate the Surgical Planning process will reduce the individual expertise needed and encourage use in the clinic by clinicians. As post-operative physiologic predictions improve, Fontan Surgical Planning will become an more effective tool to accurately model patient-specific hemodynamics.
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Surgical Planning of the total cavopulmonary connection robustness analysis
Annals of Biomedical Engineering, 2015Co-Authors: Maria Restrepo, Mark Luffel, Jake Sebring, Kirk R Kanter, Pedro J Del Nido, Alessandro Veneziani, Jarek Rossignac, Ajit P YoganathanAbstract:In Surgical Planning of the Fontan connection for single ventricle physiologies, there can be differences between the proposed and implemented options. Here, we developed a Surgical Planning framework that help determine the best performing option and ensures that the results will be comparable if there are slight geometrical variations. Eight patients with different underlying anatomies were evaluated in this study; Surgical variations were created for each connection by changing either angle, offset or baffle diameter. Computational fluid dynamics were performed and the energy efficiency (indexed power loss-iPL) and hepatic flow distribution (HFD) computed. Differences with the original connection were evaluated: iPL was not considerably affected by the changes in geometry. For HFD, the single superior vena cava (SVC) connections presented less variability compared to the other anatomies. The Y-graft connection was the most robust overall, while the extra-cardiac connections showed dependency to offset. Bilateral SVC and interrupted inferior vena cava with azygous continuation showed high variability in HFD. We have developed a framework to assess the robustness of a Surgical option for the TCPC; this will be useful to assess the most complex cases where pre-surgery Planning could be most beneficial to ensure an efficient and robust hemodynamic performance.
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correction of pulmonary arteriovenous malformation using image based Surgical Planning
Jacc-cardiovascular Imaging, 2009Co-Authors: Kartik S Sundareswaran, Kirk R Kanter, Jarek Rossignac, Thomas L Spray, Mark A Fogel, Diane De Zelicourt, Shiva Sharma, Fotis Sotiropoulos, Ajit P YoganathanAbstract:The objectives of this study were to develop an image-based Surgical Planning framework that 1) allows for in-depth analysis of pre-operative hemodynamics by the use of cardiac magnetic resonance and 2) enables surgeons to determine the optimum Surgical scenarios before the operation. This framework is tailored for applications in which post-operative hemodynamics are important. In particular, it is exemplified here for a Fontan patient with severe left pulmonary arteriovenous malformations due to abnormal hepatic flow distribution to the lungs. Patients first undergo cardiac magnetic resonance for 3-dimensional anatomy and flow reconstruction. After analysis of the pre-operative flow fields, the 3-dimensional anatomy is imported into an interactive Surgical Planning interface for the surgeon to virtually perform multiple Surgical scenarios. Associated hemodynamics are predicted by the use of a fully validated computational fluid dynamic solver. Finally, efficiency metrics (e.g., pressure decrease and hepatic flow distribution) are weighted against Surgical feasibility to determine the optimal Surgical option.
Stefan Weber - One of the best experts on this subject based on the ideXlab platform.
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Surgical Planning tool for robotically assisted hearing aid implantation
Computer Assisted Radiology and Surgery, 2014Co-Authors: Nicolas Gerber, Brett Bell, Kate Gavaghan, Christian Weisstanner, Marco Caversaccio, Stefan WeberAbstract:For the facilitation of minimally invasive robotically performed direct cochlea access (DCA) procedure, a Surgical Planning tool which enables the surgeon to define landmarks for patient-to-image registration, identify the necessary anatomical structures and define a safe DCA trajectory using patient image data (typically computed tomography (CT) or cone beam CT) is required. To this end, a dedicated end-to-end software Planning system for the Planning of DCA procedures that addresses current deficiencies has been developed. Efficient and robust anatomical segmentation is achieved through the implementation of semiautomatic algorithms; high-accuracy patient-to-image registration is achieved via an automated model-based fiducial detection algorithm and functionality for the interactive definition of a safe drilling trajectory based on case-specific drill positioning uncertainty calculations was developed. The accuracy and safety of the presented software tool were validated during the conduction of eight DCA procedures performed on cadaver heads. The plan for each ear was completed in less than 20 min, and no damage to vital structures occurred during the procedures. The integrated fiducial detection functionality enabled final positioning accuracies of $$0.15\pm 0.08$$ mm. Results of this study demonstrated that the proposed software system could aid in the safe Planning of a DCA tunnel within an acceptable time.
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Surgical Planning tool for robotically assisted hearing aid implantation
Computer Assisted Radiology and Surgery, 2014Co-Authors: Nicolas Gerber, Brett Bell, Kate Gavaghan, Christian Weisstanner, Marco Caversaccio, Stefan WeberAbstract:Purpose For the facilitation of minimally invasive robotically performed direct cochlea access (DCA) procedure, a Surgical Planning tool which enables the surgeon to define landmarks for patient-to-image registration, identify the necessary anatomical structures and define a safe DCA trajectory using patient image data (typically computed tomography (CT) or cone beam CT) is required. To this end, a dedicated end-to-end software Planning system for the Planning of DCA procedures that addresses current deficiencies has been developed.
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Three-dimensional printing creates models for Surgical Planning of aortic valve replacement after previous coronary bypass grafting.
The Annals of thoracic surgery, 2008Co-Authors: Ralf Sodian, Stefan Weber, Mathias Markert, Tim C Lueth, Daniel Schmauss, Konstantin Nikolaou, Sandra Haeberle, Ferdinand Vogt, Calin Vicol, Bruno ReichartAbstract:Purpose Resternotomy for aortic valve replacement in patients with previous coronary artery bypass grafting and an internal mammary artery graft may be a Surgical problem. Thus, we are exploring the effect of using rapid prototyping techniques for Surgical Planning and intraoperative orientation during aortic valve replacement after previous coronary artery bypass grafting (CABG). Description As a proof of concept, we studied a patient who had undergone CABG 5 years earlier. At that time the patient received a left internal mammary artery graft to the left anterior descending artery and a venous graft to the right coronary artery. Now the patient required aortic valve replacement due to symptomatic aortic valve stenosis. The left internal mammary artery bypass and the right coronary artery bypass were patent and showed good flow in the angiography. The patient was examined by 128-slice computed tomography. The image data were visualized and reconstructed. Afterwards, a replica showing the anatomic structures was fabricated using a rapid prototyping machine. Evaluation Using data derived from 128-slice computed tomography angiography linked to proprietary software, we were able to create three-dimensional reconstructions of the vascular anatomy after the previous CABG. The models were sterilized and taken to the operating theatre for orientation during the Surgical procedure. Conclusions Stereolithographic replicas are helpful for choosing treatment strategies in Surgical Planning and for intraoperative orientation during reoperations of patients with previous CABG.
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stereolithographic models for Surgical Planning in congenital heart surgery
The Annals of Thoracic Surgery, 2007Co-Authors: Ralf Sodian, Stefan Weber, Mathias Markert, Darius Rassoulian, I Kaczmarek, Tim C Lueth, Bruno Reichart, Sabine DaebritzAbstract:Purpose Currently we are exploring the impact of using rapid prototyping techniques for Surgical Planning and intraoperative orientation during the correction of complex congenital malformation. Description We studied a patient with a left abnormal subclavian artery and right descending aorta as a rare cause of dyspnea and dysphagia. The patient was examined by magnetic resonance imaging angiography. The image data were visualized and reconstructed. Afterward a replica of the malformation was fabricated using a rapid prototyping machine. In addition, a stereolithographic model of an intracardiac lesion (ventricular septal defect) was fabricated with data obtained from a computed tomographic scan. Evaluation Using data derived from a magnetic resonance imaging angiography or computed tomographic scan linked to proprietary software, we were able to create three-dimensional reconstructions of complex vascular pathology and intracardiac lesions. In addition, we fabricated replicas of congenital malformations using a rapid prototyping machine. The models could be sterilized and taken to the operating room for orientation during the corrective Surgical procedure. Conclusions Stereolithographic replicas are helpful for choosing treatment strategies, Surgical Planning of corrections, and intraoperative orientation, and as demonstrations on life-like models for the patient.
Linping Zhao - One of the best experts on this subject based on the ideXlab platform.
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application of virtual Surgical Planning with computer assisted design and manufacturing technology to cranio maxillofacial surgery
Archives of Plastic Surgery, 2012Co-Authors: Linping Zhao, Pravin K Patel, Mimis CohenAbstract:Computer aided design and manufacturing (CAD/CAM) technology today is the standard in manufacturing industry. The application of the CAD/CAM technology, together with the emerging 3D medical images based virtual Surgical Planning (VSP) technology, to craniomaxillofacial reconstruction has been gaining increasing attention to reconstructive surgeons. This article illustrates the components, system and clinical management of the VSP and CAD/CAM technology including: data acquisition, virtual Surgical and treatment Planning, individual implant design and fabrication, and outcome assessment. It focuses primarily on the technical aspects of the VSP and CAD/CAM system to improve the predictability of the Planning and outcome.
Mimis Cohen - One of the best experts on this subject based on the ideXlab platform.
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application of virtual Surgical Planning with computer assisted design and manufacturing technology to cranio maxillofacial surgery
Archives of Plastic Surgery, 2012Co-Authors: Linping Zhao, Pravin K Patel, Mimis CohenAbstract:Computer aided design and manufacturing (CAD/CAM) technology today is the standard in manufacturing industry. The application of the CAD/CAM technology, together with the emerging 3D medical images based virtual Surgical Planning (VSP) technology, to craniomaxillofacial reconstruction has been gaining increasing attention to reconstructive surgeons. This article illustrates the components, system and clinical management of the VSP and CAD/CAM technology including: data acquisition, virtual Surgical and treatment Planning, individual implant design and fabrication, and outcome assessment. It focuses primarily on the technical aspects of the VSP and CAD/CAM system to improve the predictability of the Planning and outcome.
Kirk R Kanter - One of the best experts on this subject based on the ideXlab platform.
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the first cohort of prospective fontan Surgical Planning patients with follow up data how accurate is Surgical Planning
The Journal of Thoracic and Cardiovascular Surgery, 2019Co-Authors: Phillip M Trusty, Kirk R Kanter, Zhenglun Alan Wei, Timothy C Slesnick, Thomas L Spray, Mark A Fogel, Ajit P YoganathanAbstract:Abstract Objective Fontan Surgical Planning is an image-based, collaborative effort, which is hypothesized to result in improved patient outcomes. A common motivation for Fontan Surgical Planning is the progression (or concern for progression) of pulmonary arteriovenous malformations. The purpose of this study was to evaluate the accuracy of Surgical Planning predictions, specifically hepatic flow distribution (HFD), a known factor in pulmonary arteriovenous malformation progression, and identify methodological improvements needed to increase prediction accuracy. Methods Twelve single-ventricle patients who were enrolled in a Surgical Planning protocol for Fontan surgery with pre- and postoperative cardiac imaging were included in this study. Computational fluid dynamics were used to compare HFD in the Surgical Planning prediction and actual postoperative conditions. Results Overall, HFD prediction error was 17 ± 13%. This error was similar between surgery types (15 ± 18% and 18 ± 10% for revisions vs Fontan completions respectively; P = .73), but was significantly lower (6 ± 7%; P = .05) for hepatic to azygous shunts. Y-grafts and extracardiac conduits showed a strong correlation between prediction error and discrepancies in graft insertion points (r = 0.99; P Conclusions Although Fontan Surgical Planning can offer accurate HFD predictions for specific graft types, methodological improvements are needed to increase overall accuracy. Specifically, improving postoperative anatomy prediction was shown to be an important target for future work. Future efforts and refinements to the Surgical Planning process will benefit from an improved understanding of the current state and will rely heavily on increased follow-up data.
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fontan Surgical Planning previous accomplishments current challenges and future directions
Journal of Cardiovascular Translational Research, 2018Co-Authors: Phillip M Trusty, Kirk R Kanter, Jarek Rossignac, Zhenglun Alan Wei, Timothy C Slesnick, Mark A Fogel, Ajit P YoganathanAbstract:The ultimate goal of Fontan Surgical Planning is to provide additional insights into the clinical decision-making process. In its current state, Surgical Planning offers an accurate hemodynamic assessment of the pre-operative condition, provides anatomical constraints for potential Surgical options, and produces decent post-operative predictions if boundary conditions are similar enough between the pre-operative and post-operative states. Moving forward, validation with post-operative data is a necessary step in order to assess the accuracy of Surgical Planning and determine which methodological improvements are needed. Future efforts to automate the Surgical Planning process will reduce the individual expertise needed and encourage use in the clinic by clinicians. As post-operative physiologic predictions improve, Fontan Surgical Planning will become an more effective tool to accurately model patient-specific hemodynamics.
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Surgical Planning of the total cavopulmonary connection robustness analysis
Annals of Biomedical Engineering, 2015Co-Authors: Maria Restrepo, Mark Luffel, Jake Sebring, Kirk R Kanter, Pedro J Del Nido, Alessandro Veneziani, Jarek Rossignac, Ajit P YoganathanAbstract:In Surgical Planning of the Fontan connection for single ventricle physiologies, there can be differences between the proposed and implemented options. Here, we developed a Surgical Planning framework that help determine the best performing option and ensures that the results will be comparable if there are slight geometrical variations. Eight patients with different underlying anatomies were evaluated in this study; Surgical variations were created for each connection by changing either angle, offset or baffle diameter. Computational fluid dynamics were performed and the energy efficiency (indexed power loss-iPL) and hepatic flow distribution (HFD) computed. Differences with the original connection were evaluated: iPL was not considerably affected by the changes in geometry. For HFD, the single superior vena cava (SVC) connections presented less variability compared to the other anatomies. The Y-graft connection was the most robust overall, while the extra-cardiac connections showed dependency to offset. Bilateral SVC and interrupted inferior vena cava with azygous continuation showed high variability in HFD. We have developed a framework to assess the robustness of a Surgical option for the TCPC; this will be useful to assess the most complex cases where pre-surgery Planning could be most beneficial to ensure an efficient and robust hemodynamic performance.
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correction of pulmonary arteriovenous malformation using image based Surgical Planning
Jacc-cardiovascular Imaging, 2009Co-Authors: Kartik S Sundareswaran, Kirk R Kanter, Jarek Rossignac, Thomas L Spray, Mark A Fogel, Diane De Zelicourt, Shiva Sharma, Fotis Sotiropoulos, Ajit P YoganathanAbstract:The objectives of this study were to develop an image-based Surgical Planning framework that 1) allows for in-depth analysis of pre-operative hemodynamics by the use of cardiac magnetic resonance and 2) enables surgeons to determine the optimum Surgical scenarios before the operation. This framework is tailored for applications in which post-operative hemodynamics are important. In particular, it is exemplified here for a Fontan patient with severe left pulmonary arteriovenous malformations due to abnormal hepatic flow distribution to the lungs. Patients first undergo cardiac magnetic resonance for 3-dimensional anatomy and flow reconstruction. After analysis of the pre-operative flow fields, the 3-dimensional anatomy is imported into an interactive Surgical Planning interface for the surgeon to virtually perform multiple Surgical scenarios. Associated hemodynamics are predicted by the use of a fully validated computational fluid dynamic solver. Finally, efficiency metrics (e.g., pressure decrease and hepatic flow distribution) are weighted against Surgical feasibility to determine the optimal Surgical option.
