The Experts below are selected from a list of 16635 Experts worldwide ranked by ideXlab platform
Wiro J. Niessen - One of the best experts on this subject based on the ideXlab platform.
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Guide Wire reconstruction and visualization in 3DRA using monoplane fluoroscopic imaging
IEEE Transactions on Medical Imaging, 2005Co-Authors: T. Van Walsum, S.a.m. Baert, Wiro J. NiessenAbstract:A method has been developed that, based on the Guide Wire position in monoplane fluoroscopic images, visualizes the approximate Guide Wire position in the three-dimensional (3-D) vasculature, that is obtained prior to the intervention with 3-D rotational X-ray angiography (3DRA). The method assumes the position of the Guide Wire in the fluoroscopic images is known. A two-dimensional feature image is determined from the 3DRA data. In this feature image, the Guide Wire position is determined in a two-step approach: a mincost algorithm is used to determine a suitable position for the Guide Wire, and subsequently a snake optimization technique is applied to move the Guide Wire to a better position. The resulting Guide Wire can then be visualized in 3-D in combination with the 3DRA dataset. The reconstruction accuracy of the method has been evaluated using a 3DRA image of a vascular phantom filled with contrast, and monoplane fluoroscopic images of the same phantom without contrast and with a Guide Wire inserted. The evaluation has been performed for different projection angles, and with different parameters for the method. The final result does not appear to be very sensitive to the parameters of the method. The average mean error of the estimated 3-D Guide Wire position is 1.5 mm, and the average tip distance is 2.3 mm. The effect of inaccurate C-arm geometry information is also investigated. Small errors in geometry information (up to 1/spl deg/) will slightly decrease the 3-D reconstruction accuracies, with an error of at most 1 mm. The feasibility of this approach on clinical data is demonstrated.
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analytical Guide Wire motion algorithm for simulation of endovascular interventions
Medical & Biological Engineering & Computing, 2003Co-Authors: Maurits K Konings, E B Van De Kraats, T Alderliesten, Wiro J. NiessenAbstract:Performing minimally invasive vascular interventions requires proper training, as a Guide Wire needs to be manipulated, by the tail, under fluoroscopic guidance. To provide a training environment, the motion of the Guide Wire inside the human vasculature can be simulated by computer. Such a simulation needs to be based on an algorithm that is both realistic and fast. To meet these two demands, an analytical solution to the problem of Guide Wire motion has been derived, using a new parametrisation of Guide Wire shape. The algorithm is highly generic, is entirely based on elementary physics and has good convergence properties (accuracy of 22 micron after two iterations). In an experimental validation of the algorithm in a planar model, the RMS of the spatial discrepancy between the real and simulated catheter positions was about 10% of the lumen size. Comparison of the simulated Guide Wire motion with 3D rotational angiography data of a real Guide Wire advanced in a plastic phantom of the cerebral vasculature showed that the new algorithm produced realistic results.
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three dimensional Guide Wire reconstruction from biplane image sequences for integrated display in 3 d vasculature
IEEE Transactions on Medical Imaging, 2003Co-Authors: S.a.m. Baert, Max A. Viergever, T. Van Walsum, E B Van De Kraats, Wiro J. NiessenAbstract:Using three-dimensional rotational X-ray angiography (3DRA), three-dimensional (3-D) information of the vasculature can be obtained prior to endovascular interventions. However, during interventions, the radiologist has to rely on fluoroscopy images to manipulate the Guide Wire. In order to take full advantage of the 3-D information from 3DRA data during endovascular interventions, a method is presented that yields an integrated display of the position of the Guide Wire and vasculature in 3-D. The method relies on an automated method that tracks the Guide Wire simultaneously in biplane fluoroscopy images. Based on the calibrated geometry of the C-arm, the 3-D Guide-Wire position is determined and visualized in the 3-D coordinate system of the vasculature. The method is evaluated in an intracranial anthropomorphic vascular phantom. The influence of the angle between projections, distortion correction of the projection images, and accuracy of geometry knowledge on the accuracy of 3-D Guide-Wire reconstruction from biplane images is determined. If the calibrated geometry information is used and the images are corrected for distortion, a mean distance to the reference standard of 0.42 mm and a tip distance of 0.65 mm is found, which means that accurate Guide-Wire reconstruction from biplane images can be performed.
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Guide-Wire tracking during endovascular interventions
IEEE Transactions on Medical Imaging, 2003Co-Authors: Baert Sam, Max A. Viergever, Wiro J. NiessenAbstract:A method is presented to extract and track the position of a Guide Wire during endovascular interventions under X-ray fluoroscopy. The method can be used to improve Guide-Wire visualization in low-quality fluoroscopic images and to estimate the position of the Guide Wire in world coordinates. A two-step procedure is utilized to track the Guide Wire in subsequent frames. First, a rough estimate of the displacement is obtained using a template-matching procedure. Subsequently, the position of the Guide Wire is determined by fitting a spline to a feature image. The feature images that have been considered enhance line-like structures on: 1) the original images; 2) subtraction images; and 3) preprocessed images in which coherent structures are enhanced. In the optimization step, the influence of the scale at which the feature is calculated and the additional value of using directional information is investigated. The method is evaluated on 267 frames from ten clinical image sequences. Using the automatic method, the Guide Wire could be tracked in 96% of the frames, with a similar accuracy to three observers, although the position of the tip was estimated less accurately.
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Endpoint localization in Guide Wire tracking during endovascular interventions1
Academic Radiology, 2003Co-Authors: S.a.m. Baert, Theo Van Walsum, Wiro J. NiessenAbstract:Rationale and Objectives. A method is presented to track Guide Wires during endovascular interventions under X-ray fluoroscopy. Accurate Guide Wire tracking can be used to improve Guide Wire visualization in the low quality fluoroscopic images, and to estimate the position of the Guide Wire in world coordinates for navigation purposes. Materials and Methods. A two-step procedure is used to track the Guide Wire in subsequent frames. First, the position of the Guide Wire is obtained by fitting a spline to the image. Subsequently, the spline is iteratively moved toward the tip of the Guide Wire for accurate tip localization. For both steps, a feature image is used in which line-like structures are enhanced. The method is validated using a reference standard, obtained by manual tracings of three observers. Results. The method is evaluated on 20 image sequences, 10 sequences with a J-tipped Guide Wire and 10 with a straight Guide Wire. The tracking success was 96% for J-tipped and 100% for straight Guide Wires, whereas accurate endpoint localization could be performed in 91.3% and 94.4% of the frames respectively, with a tip localization error of less than 1.5 mm. Conclusions. Accurate endpoint localization can be performed for both J-tipped and straight Guide Wires and therefore the presented tracking method can be used for navigation purposes.
S.a.m. Baert - One of the best experts on this subject based on the ideXlab platform.
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Guide Wire reconstruction and visualization in 3DRA using monoplane fluoroscopic imaging
IEEE Transactions on Medical Imaging, 2005Co-Authors: T. Van Walsum, S.a.m. Baert, Wiro J. NiessenAbstract:A method has been developed that, based on the Guide Wire position in monoplane fluoroscopic images, visualizes the approximate Guide Wire position in the three-dimensional (3-D) vasculature, that is obtained prior to the intervention with 3-D rotational X-ray angiography (3DRA). The method assumes the position of the Guide Wire in the fluoroscopic images is known. A two-dimensional feature image is determined from the 3DRA data. In this feature image, the Guide Wire position is determined in a two-step approach: a mincost algorithm is used to determine a suitable position for the Guide Wire, and subsequently a snake optimization technique is applied to move the Guide Wire to a better position. The resulting Guide Wire can then be visualized in 3-D in combination with the 3DRA dataset. The reconstruction accuracy of the method has been evaluated using a 3DRA image of a vascular phantom filled with contrast, and monoplane fluoroscopic images of the same phantom without contrast and with a Guide Wire inserted. The evaluation has been performed for different projection angles, and with different parameters for the method. The final result does not appear to be very sensitive to the parameters of the method. The average mean error of the estimated 3-D Guide Wire position is 1.5 mm, and the average tip distance is 2.3 mm. The effect of inaccurate C-arm geometry information is also investigated. Small errors in geometry information (up to 1/spl deg/) will slightly decrease the 3-D reconstruction accuracies, with an error of at most 1 mm. The feasibility of this approach on clinical data is demonstrated.
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three dimensional Guide Wire reconstruction from biplane image sequences for integrated display in 3 d vasculature
IEEE Transactions on Medical Imaging, 2003Co-Authors: S.a.m. Baert, Max A. Viergever, T. Van Walsum, E B Van De Kraats, Wiro J. NiessenAbstract:Using three-dimensional rotational X-ray angiography (3DRA), three-dimensional (3-D) information of the vasculature can be obtained prior to endovascular interventions. However, during interventions, the radiologist has to rely on fluoroscopy images to manipulate the Guide Wire. In order to take full advantage of the 3-D information from 3DRA data during endovascular interventions, a method is presented that yields an integrated display of the position of the Guide Wire and vasculature in 3-D. The method relies on an automated method that tracks the Guide Wire simultaneously in biplane fluoroscopy images. Based on the calibrated geometry of the C-arm, the 3-D Guide-Wire position is determined and visualized in the 3-D coordinate system of the vasculature. The method is evaluated in an intracranial anthropomorphic vascular phantom. The influence of the angle between projections, distortion correction of the projection images, and accuracy of geometry knowledge on the accuracy of 3-D Guide-Wire reconstruction from biplane images is determined. If the calibrated geometry information is used and the images are corrected for distortion, a mean distance to the reference standard of 0.42 mm and a tip distance of 0.65 mm is found, which means that accurate Guide-Wire reconstruction from biplane images can be performed.
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Endpoint localization in Guide Wire tracking during endovascular interventions1
Academic Radiology, 2003Co-Authors: S.a.m. Baert, Theo Van Walsum, Wiro J. NiessenAbstract:Rationale and Objectives. A method is presented to track Guide Wires during endovascular interventions under X-ray fluoroscopy. Accurate Guide Wire tracking can be used to improve Guide Wire visualization in the low quality fluoroscopic images, and to estimate the position of the Guide Wire in world coordinates for navigation purposes. Materials and Methods. A two-step procedure is used to track the Guide Wire in subsequent frames. First, the position of the Guide Wire is obtained by fitting a spline to the image. Subsequently, the spline is iteratively moved toward the tip of the Guide Wire for accurate tip localization. For both steps, a feature image is used in which line-like structures are enhanced. The method is validated using a reference standard, obtained by manual tracings of three observers. Results. The method is evaluated on 20 image sequences, 10 sequences with a J-tipped Guide Wire and 10 with a straight Guide Wire. The tracking success was 96% for J-tipped and 100% for straight Guide Wires, whereas accurate endpoint localization could be performed in 91.3% and 94.4% of the frames respectively, with a tip localization error of less than 1.5 mm. Conclusions. Accurate endpoint localization can be performed for both J-tipped and straight Guide Wires and therefore the presented tracking method can be used for navigation purposes.
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MICCAI (2) - 2D Guide Wire Tracking during Endovascular Interventions
Medical Image Computing and Computer-Assisted Intervention — MICCAI 2002, 2002Co-Authors: S.a.m. Baert, Wiro J. Niessen, Erik Meijering, Alejandro F. Frangi, Max A. ViergeverAbstract:A method to extract and track the position of a Guide Wire during endovascular interventions under X-ray fluoroscopy is presented and evaluated. The method can be used to improve Guide Wire visualization in the low quality fluoroscopic images and to estimate the position of the Guide Wire in world coordinates. A two-step procedure is utilized to track the Guide Wire in subsequent frames. First a rough estimate of the displacement is obtained using a template matching procedure. Subsequently, the position of the Guide Wire is determined by fitting a spline to a feature image in which line-like structures are enhanced. In the optimization step, the influence of the scale at which the feature is calculated is investigated. Also, the feature image is calculated both on the original image and on a preprocessed image in which coherent structures are enhanced. Finally, the influence of explicit endpoint detection is studied. The method is evaluated on 267 frames from 10 sequences. Using the automatic method, the Guide Wire could be tracked in 96% of the frames, with a greater accuracy than three observers. Endpoint detection improved the accuracy of the tip assessment, which was better than 1.3 mm.
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Improved endpoint localization in Guide Wire tracking during endovascular interventions
CARS 2002 Computer Assisted Radiology and Surgery, 2002Co-Authors: S.a.m. Baert, Wiro J. NiessenAbstract:A method is presented which improves endpoint localization in Guide Wire tracking during endovascular interventions under X-ray fluoroscopy. Accurate Guide Wire tracking can be used to improve Guide Wire visualization in the low quality fluoroscopic images, and to estimate the Guide Wire position in world coordinates. Guide Wire tracking is performed using a two-step approach: first, the position of the Guide Wire is obtained by fitting a spline using a feature image. Subsequently, the spline is iteratively moved towards the tip of the Guide Wire for more accurate tip localization. For both steps a feature image is calculated in which line-like structures are enhanced. The method is validated using a golden standard, obtained by manual tracings of three observers. By comparing the results to Guide Wire tracking without explicit endpoint detection, we found that accurate tip localization significantly improved localization accuracy.
Roy L Gordon - One of the best experts on this subject based on the ideXlab platform.
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catheter tract hemorrhage during percutaneous biliary intervention management with use of a retained transhepatic Guide Wire
Journal of Vascular and Interventional Radiology, 1995Co-Authors: Eric W Olcott, Richard R Saxon, Ernest J Ring, Roy L GordonAbstract:Purpose The authors present their experience in managing freely flowing hemorrhage from immature catheter tracts in patients undergoing biliary drainage. Patients and Methods Transhepatic Guide Wires were maintained securely whenever catheters were removed from the liver. Six patients among 71 hemorrhaged profusely when drains were manipulated within 4 days of initial catheterization. Management was attempted with use of the transhepatic Guide Wires. Results Maneuvers performed over the retained Guide Wire controlled bleeding in all six patients. Reintubation constituted definitive therapy in five patients. A biliary-portal venous fistula in the remaining patient was treated with thrombin. The retained Guide Wire proved necessary in all cases. Conclusions Hemorrhage from immature catheter tracts can be managed, often definitively, with maneuvers performed over a retained transhepatic Guide Wire. Accordingly, a secure transhepatic Guide Wire is essential prior to removal of hepatic catheters and should remain in place until the absence of bleeding is established. These maneuvers may become increasingly important as courses of biliary catheterization become shorter.
K. R. Baghavan - One of the best experts on this subject based on the ideXlab platform.
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Case Report-Guide-Wire embolism during subclavian vein catheterizationby Seldinger technique
2007Co-Authors: H. Narendra, K. R. BaghavanAbstract:Percutaneous cannulation of central veins by Seldinger technique is a popular approach in intensive care settings. We report a case of embolization of a complete Guide-Wire during such a procedure. Our case differs from the few earlier reported cases in that subclavian vein was the entry site. While reviewing the available literature, we discuss few reasons and management of such a mishap.
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Guide-Wire embolism during subclavian vein catheterization by Seldinger technique
Indian Journal of Critical Care Medicine, 2006Co-Authors: H. Narendra, K. R. BaghavanAbstract:Percutaneous cannulation of central veins by Seldinger technique is a popular approach in intensive care settings. We report a case of embolization of a complete Guide-Wire during such a procedure. Our case differs from the few earlier reported cases in that subclavian vein was the entry site. While reviewing the available literature, we discuss few reasons and management of such a mishap.
Eric W Olcott - One of the best experts on this subject based on the ideXlab platform.
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catheter tract hemorrhage during percutaneous biliary intervention management with use of a retained transhepatic Guide Wire
Journal of Vascular and Interventional Radiology, 1995Co-Authors: Eric W Olcott, Richard R Saxon, Ernest J Ring, Roy L GordonAbstract:Purpose The authors present their experience in managing freely flowing hemorrhage from immature catheter tracts in patients undergoing biliary drainage. Patients and Methods Transhepatic Guide Wires were maintained securely whenever catheters were removed from the liver. Six patients among 71 hemorrhaged profusely when drains were manipulated within 4 days of initial catheterization. Management was attempted with use of the transhepatic Guide Wires. Results Maneuvers performed over the retained Guide Wire controlled bleeding in all six patients. Reintubation constituted definitive therapy in five patients. A biliary-portal venous fistula in the remaining patient was treated with thrombin. The retained Guide Wire proved necessary in all cases. Conclusions Hemorrhage from immature catheter tracts can be managed, often definitively, with maneuvers performed over a retained transhepatic Guide Wire. Accordingly, a secure transhepatic Guide Wire is essential prior to removal of hepatic catheters and should remain in place until the absence of bleeding is established. These maneuvers may become increasingly important as courses of biliary catheterization become shorter.