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Sabee Molloi - One of the best experts on this subject based on the ideXlab platform.
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Vessel-specific coronary perfusion territories using a CT angiogram with a Minimum Cost Path technique and its direct comparison to the American Heart Association 17-segment model
European radiology, 2020Co-Authors: Shant Malkasian, Logan Hubbard, Pablo Abbona, Brian Dertli, Jungnam Kwon, Sabee MolloiAbstract:This study compared the accuracy of an automated, vessel-specific Minimum Cost Path (MCP) myocardial perfusion territory assignment technique as compared with the standard American Heart Association 17-segment (AHA) model. Six swine (42 ± 9 kg) were used to evaluate the accuracy of the MCP technique and the AHA method. In each swine, a dynamic acquisition, comprised of twenty consecutive whole heart volume scans, was acquired with a computed tomography scanner, following peripheral injection of contrast material. From this acquisition, MCP and AHA perfusion territories were determined, for the left (LCA) and right (RCA) coronary arteries. Each animal underwent additional dynamic acquisitions, consisting of twenty consecutive volume scans, following direct intracoronary contrast injection into the LCA or RCA. These images were used as the reference standard (REF) LCA and RCA perfusion territories. The MCP and AHA techniques’ perfusion territories were then quantitatively compared with the REF perfusion territories. The myocardial mass of MCP perfusion territories (MMCP) was related to the mass of reference standard perfusion territories (MREF) by MMCP = 0.99MREF + 0.39 g (r = 1.00; R2 = 1.00). The mass of AHA perfusion territories (MAHA) was related to MREF by MAHA = 0.81MREF + 5.03 g (r = 0.99; R2 = 0.98). The vessel-specific MCP myocardial perfusion territory assignment technique more accurately quantifies LCA and RCA perfusion territories as compared with the current standard AHA 17-segment model. Therefore, it can potentially provide a more comprehensive and patient-specific evaluation of coronary artery disease. • The Minimum Cost Path (MCP) technique accurately determines left and right coronary artery perfusion territories, as compared with the American Heart Association 17-segment (AHA) model. • The Minimum Cost Path (MCP) technique could be applied to cardiac computed-tomography angiography images to accurately determine patient-specific left and right coronary artery perfusion territories. • The American Heart Association 17-segment (AHA) model often fails to accurately determine left and right coronary artery perfusion territories, especially in the inferior and inferoseptal walls of the left ventricular myocardium.
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Quantification of vessel-specific coronary perfusion territories using Minimum-Cost Path assignment and computed tomography angiography: Validation in a swine model.
Journal of cardiovascular computed tomography, 2018Co-Authors: Shant Malkasian, Logan Hubbard, Brian Dertli, Jungnam Kwon, Sabee MolloiAbstract:Abstract Background As combined morphological and physiological assessment of coronary artery disease (CAD) is necessary to reliably resolve CAD severity, the objective of this study was to validate an automated Minimum-Cost Path assignment (MCP) technique which enables accurate, vessel-specific assignment of the left (LCA) and right (RCA) coronary perfusion territories using computed tomography (CT) angiography data for both left and right ventricles. Methods Six swine were used to validate the MCP technique. In each swine, a dynamic acquisition comprised of twenty consecutive volume scans was acquired with a 320-slice CT scanner following peripheral injection of contrast material. From this acquisition the MCP technique was used to automatically assign LCA and RCA perfusion territories for the left and right ventricles, independently. Each animal underwent another dynamic CT acquisition following direct injection of contrast material into the LCA or RCA. Using this acquisition, reference standard LCA and RCA perfusion territories were isolated from the myocardial blush. The accuracy of the MCP technique was evaluated by quantitatively comparing the MCP-derived LCA and RCA perfusion territories to these reference standard territories. Results All MCP perfusion territory masses (MassMCP) and all reference standard perfusion territory masses (MassRS) in the left ventricle were related by MassMCP = 0.99MassRS+0.35 g (r = 1.00). MassMCP and MassRS in the right ventricle were related by MassMCP = 0.94MassRS+0.39 g (r = 0.96). Conclusion The MCP technique was validated in a swine animal model and has the potential to be used for accurate, vessel-specific assignment of LCA and RCA perfusion territories in both the left and right ventricular myocardium using CT angiography data.
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TH-CD-206-07: Determination of Patient-Specific Myocardial Mass at Risk Using Computed Tomography Angiography
Medical Physics, 2016Co-Authors: Logan Hubbard, Shant Malkasian, Brian Dertli, B. P. Ziemer, Jerry Lipinski, Bahman Sadeghi, H. Javan, Elliott M. Groves, Sabee MolloiAbstract:Purpose: To evaluate the accuracy of a patient-specific coronary perfusion territory assignment algorithm that uses CT angiography (CTA) and a Minimum-Cost-Path approach to assign coronary perfusion territories on a voxel-by-voxel basis for determination of myocardial mass at risk. Methods: Intravenous (IV) contrast (370 mg/mL iodine, 25 mL, 7 mL/s) was injected centrally into five swine (35–45 kg) and CTA was performed using a 320-slice CT scanner at 100 kVp and 200 mA. Additionally, a 4F catheter was advanced into the left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA) and contrast (30 mg/mL iodine, 10 mL, 1.5 mL/s) was directly injected into each coronary artery for isolation of reference coronary perfusion territories. Semiautomatic myocardial segmentation of the CTA data was then performed and the centerlines of the LAD, LCX, and RCA were digitally extracted through image processing. Individual coronary perfusion territories were then assigned using a Minimum-Cost-Path approach, and were quantitatively compared to the reference coronary perfusion territories. Results: The results of the coronary perfusion territory assignment algorithm were in good agreement with the reference coronary perfusion territories. The average volumetric assignment error from mitral orifice to apex was 5.5 ± 1.1%, corresponding to 2.1 ± 0.7 grams of myocardial mass misassigned for each coronary perfusion territory. Conclusion: The results indicate that accurate coronary perfusion territory assignment is possible on a voxel-by-voxel basis using CTA data and an assignment algorithm based on a Minimum-Cost-Path approach. Thus, the technique can potentially be used to accurately determine patient-specific myocardial mass at risk distal to a coronary stenosis, improving coronary lesion assessment and treatment. Conflict of Interest (only if applicable): Grant funding from Toshiba America Medical Systems.
Wiro J. Niessen - One of the best experts on this subject based on the ideXlab platform.
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Integrated Analysis and Visualization of Group Differences in Structural and Functional Brain Connectivity: Applications in Typical Ageing and Schizophrenia
PloS one, 2015Co-Authors: Carolyn D. Langen, Meike W. Vernooij, M. Arfan Ikram, Tonya White, Wiro J. NiessenAbstract:Structural and functional brain connectivity are increasingly used to identify and analyze group differences in studies of brain disease. This study presents methods to analyze uni- and bi-modal brain connectivity and evaluate their ability to identify differences. Novel visualizations of significantly different connections comparing multiple metrics are presented. On the global level, “bi-modal comparison plots” show the distribution of uni- and bi-modal group differences and the relationship between structure and function. Differences between brain lobes are visualized using “worm plots”. Group differences in connections are examined with an existing visualization, the “connectogram”. These visualizations were evaluated in two proof-of-concept studies: (1) middle-aged versus elderly subjects; and (2) patients with schizophrenia versus controls. Each included two measures derived from diffusion weighted images and two from functional magnetic resonance images. The structural measures were Minimum Cost Path between two anatomical regions according to the “Statistical Analysis of Minimum Cost Path based Structural Connectivity” method and the average fractional anisotropy along the fiber. The functional measures were Pearson’s correlation and partial correlation of mean regional time series. The relationship between structure and function was similar in both studies. Uni-modal group differences varied greatly between connectivity types. Group differences were identified in both studies globally, within brain lobes and between regions. In the aging study, Minimum Cost Path was highly effective in identifying group differences on all levels; fractional anisotropy and mean correlation showed smaller differences on the brain lobe and regional levels. In the schizophrenia study, Minimum Cost Path and fractional anisotropy showed differences on the global level and within brain lobes; mean correlation showed small differences on the lobe level. Only fractional anisotropy and mean correlation showed regional differences. The presented visualizations were helpful in comparing and evaluating connectivity measures on multiple levels in both studies.
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cardiac motion corrected iterative cone beam ct reconstruction using a semi automatic Minimum Cost Path based coronary centerline extraction
Computerized Medical Imaging and Graphics, 2012Co-Authors: Wiro J. Niessen, Coert Metz, Michiel Schaap, Stefan Klein, Alfonso Agatino Isola, Michael GrassAbstract:In this paper a method which combines iterative computed tomography reconstruction and coronary centerline extraction technique to obtain motion artifact-free reconstructed images of the coronary arteries are proposed and evaluated. The method relies on motion-vector fields derived from a set of coronary centerlines extracted at multiple cardiac phases within the R-R interval. Hereto, start and end points are provided by the user in one time-frame only. Using an elastic image registration, these points are propagated to all the remaining cardiac phases. Consequently, a multi-phase three-dimensional coronary centerline is determined by applying a semi-automatic Minimum Cost Path based extraction method. Corresponding centerline positions are used to determine the relative motion-vector fields from phase to phase. Finally, dense motion-vector fields are achieved by thin-plate-spline interpolation and used to perform a motion-corrected iterative reconstruction of a selected region of interest. The performance of the method is validated on five patients, showing the improved sharpness of cardiac motion-corrected gated iterative reconstructions compared to the results achieved by a classical gated iterative method. The results are also compared to known manual and fully automatic coronary artery motion estimation methods.
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Statistical analysis of Minimum Cost Path based structural brain connectivity.
NeuroImage, 2010Co-Authors: Renske De Boer, Michiel Schaap, Fedde Van Der Lijn, Henri A. Vrooman, Marius De Groot, Aad Van Der Lugt, M. Arfan Ikram, Meike W. Vernooij, Monique M.b. Breteler, Wiro J. NiessenAbstract:Diffusion MRI can be used to study the structural connectivity within the brain. Brain connectivity is often represented by a binary network whose topology can be studied using graph theory. We present a framework for the construction of weighted structural brain networks, containing information about connectivity, which can be effectively analyzed using statistical methods. Network nodes are defined by segmentation of subcortical structures and by cortical parcellation. Connectivity is established using a Minimum Cost Path (mcp) method with an anisotropic local Cost function based directly on diffusion weighted images. We refer to this framework as Statistical Analysis of Minimum Cost Path based Structural Connectivity (SAMSCo) and the weighted structural connectivity networks as mcp-networks. In a proof of principle study we investigated the information contained in mcp-networks by predicting subject age based on the mcp-networks of a group of 974 middle-aged and elderly subjects. Using SAMSCo, age was predicted with an average error of 3.7 years. This was significantly better than predictions based on fractional anisotropy or mean diffusivity averaged over the whole white matter or over the corpus callosum, which showed average prediction errors of at least 4.8 years. Additionally, we classified subjects, based on the mcp-networks, into groups with low and high white matter lesion load, while correcting for age, sex and white matter atrophy. The SAMSCo classification outperformed the classification based on the diffusion measures with a classification accuracy of 76.0% versus 63.2%. We also performed a classification in groups with mild and severe atrophy, correcting for age, sex and white matter lesion load. In this case, mcp-networks and diffusion measures yielded similar classification accuracies of 68.3% and 67.8% respectively. The SAMSCo prediction and classification experiments indicate that the mcp-networks contain information regarding age, white matter lesion load and white matter atrophy, and that in case of age and white matter lesion load the mcp-network based models outperformed the predictions based on diffusion measures.
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coronary centerline extraction from ct coronary angiography images using a Minimum Cost Path approach
Medical Physics, 2009Co-Authors: Coert Metz, Michiel Schaap, T Van Walsum, Annick C. Weustink, Nico R Mollet, Wiro J. NiessenAbstract:Purpose: The application and large-scale evaluation of Minimum Cost Path approaches for coronary centerline extraction from computed tomography coronary angiography (CTCA) data and the development and evaluation of a novel method to reduce the user-interaction time. Methods: A semiautomatic method based on a Minimum Cost Path approach is evaluated for two different Cost functions. The first Cost function is based on a frequently used vesselness measure and intensity information, and the second is a recently proposed Cost function based on region statistics. User interaction is minimized to one or two mouse clicks distally in the coronary artery. The starting point for the Minimum Cost Path search is automatically determined using a newly developed method that finds a point in the center of the aorta in one of the axial slices. This step ensures that all computationally expensive parts of the algorithm can be precomputed. Results: The performance of the aorta localization procedure was demonstrated by a success rate of 100% in 75 images. The success rate and accuracy of centerline extraction was quantitatively evaluated on 48 coronary arteries in 12 images by comparing extracted centerlines with a manually annotated reference standard. The method was able to extract 88% and 47% of the vessel centerlines correctly using the vesselness/intensity and region statistics Cost function, respectively. For only the proximal part of the vessels these values were 97% and 86%, respectively. Accuracy of centerline extraction, defined as the average distance from correctly automatically extracted parts of the centerline to the reference standard, was 0.64 mm for the vesselness/intensity and 0.51 mm for the region statistics Cost function. The interobserver variability was 99% for the success rate measure and 0.42 mm for the accuracy measure. Qualitative evaluation using the best performing Cost function resulted in successful centerline extraction for 233 out of the 252 coronaries (92%) in 63 additional CTCA images. Conclusions: The presented results, in combination with minimal user interaction and low computation time, show that Minimum Cost Path approaches can effectively be applied as a preprocessing step for subsequent analysis in clinical practice and biomedical research.
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Minimum Cost Path algorithm for coronary artery central axis tracking in ct images
Medical Image Computing and Computer-Assisted Intervention, 2003Co-Authors: Marcel Breeuwer, Wiro J. Niessen, Silvia D. OlabarriagaAbstract:The quality of cardiac images acquired with multi-detector CT scanners has improved significantly, to the point where minimally invasive examination of the coronary arteries became reality. The interpretation of such images requires efficient post-processing tools to isolate the vessels from other structures, such that they can be properly analyzed quantitatively or visually. In this paper we evaluate a method for semi-automated extraction of the central axis of coronary arteries in these images. First the vessels are enhanced with a local filter that analyzes the main modes of second-order variation in image intensity to determine the type of local structure. Secondly, the extremities of the axis are indicated by the user. Finally, a connected Path between the given points is automatically determined with a Minimum Cost Path algorithm, where the Cost corresponds to the reciprocal of the enhanced image. The results obtained with different vessel enhancement filters are compared with manually traced axes in the evaluation of 15 cases.
Shant Malkasian - One of the best experts on this subject based on the ideXlab platform.
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Vessel-specific coronary perfusion territories using a CT angiogram with a Minimum Cost Path technique and its direct comparison to the American Heart Association 17-segment model
European radiology, 2020Co-Authors: Shant Malkasian, Logan Hubbard, Pablo Abbona, Brian Dertli, Jungnam Kwon, Sabee MolloiAbstract:This study compared the accuracy of an automated, vessel-specific Minimum Cost Path (MCP) myocardial perfusion territory assignment technique as compared with the standard American Heart Association 17-segment (AHA) model. Six swine (42 ± 9 kg) were used to evaluate the accuracy of the MCP technique and the AHA method. In each swine, a dynamic acquisition, comprised of twenty consecutive whole heart volume scans, was acquired with a computed tomography scanner, following peripheral injection of contrast material. From this acquisition, MCP and AHA perfusion territories were determined, for the left (LCA) and right (RCA) coronary arteries. Each animal underwent additional dynamic acquisitions, consisting of twenty consecutive volume scans, following direct intracoronary contrast injection into the LCA or RCA. These images were used as the reference standard (REF) LCA and RCA perfusion territories. The MCP and AHA techniques’ perfusion territories were then quantitatively compared with the REF perfusion territories. The myocardial mass of MCP perfusion territories (MMCP) was related to the mass of reference standard perfusion territories (MREF) by MMCP = 0.99MREF + 0.39 g (r = 1.00; R2 = 1.00). The mass of AHA perfusion territories (MAHA) was related to MREF by MAHA = 0.81MREF + 5.03 g (r = 0.99; R2 = 0.98). The vessel-specific MCP myocardial perfusion territory assignment technique more accurately quantifies LCA and RCA perfusion territories as compared with the current standard AHA 17-segment model. Therefore, it can potentially provide a more comprehensive and patient-specific evaluation of coronary artery disease. • The Minimum Cost Path (MCP) technique accurately determines left and right coronary artery perfusion territories, as compared with the American Heart Association 17-segment (AHA) model. • The Minimum Cost Path (MCP) technique could be applied to cardiac computed-tomography angiography images to accurately determine patient-specific left and right coronary artery perfusion territories. • The American Heart Association 17-segment (AHA) model often fails to accurately determine left and right coronary artery perfusion territories, especially in the inferior and inferoseptal walls of the left ventricular myocardium.
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Quantification of vessel-specific coronary perfusion territories using Minimum-Cost Path assignment and computed tomography angiography: Validation in a swine model.
Journal of cardiovascular computed tomography, 2018Co-Authors: Shant Malkasian, Logan Hubbard, Brian Dertli, Jungnam Kwon, Sabee MolloiAbstract:Abstract Background As combined morphological and physiological assessment of coronary artery disease (CAD) is necessary to reliably resolve CAD severity, the objective of this study was to validate an automated Minimum-Cost Path assignment (MCP) technique which enables accurate, vessel-specific assignment of the left (LCA) and right (RCA) coronary perfusion territories using computed tomography (CT) angiography data for both left and right ventricles. Methods Six swine were used to validate the MCP technique. In each swine, a dynamic acquisition comprised of twenty consecutive volume scans was acquired with a 320-slice CT scanner following peripheral injection of contrast material. From this acquisition the MCP technique was used to automatically assign LCA and RCA perfusion territories for the left and right ventricles, independently. Each animal underwent another dynamic CT acquisition following direct injection of contrast material into the LCA or RCA. Using this acquisition, reference standard LCA and RCA perfusion territories were isolated from the myocardial blush. The accuracy of the MCP technique was evaluated by quantitatively comparing the MCP-derived LCA and RCA perfusion territories to these reference standard territories. Results All MCP perfusion territory masses (MassMCP) and all reference standard perfusion territory masses (MassRS) in the left ventricle were related by MassMCP = 0.99MassRS+0.35 g (r = 1.00). MassMCP and MassRS in the right ventricle were related by MassMCP = 0.94MassRS+0.39 g (r = 0.96). Conclusion The MCP technique was validated in a swine animal model and has the potential to be used for accurate, vessel-specific assignment of LCA and RCA perfusion territories in both the left and right ventricular myocardium using CT angiography data.
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TH-CD-206-07: Determination of Patient-Specific Myocardial Mass at Risk Using Computed Tomography Angiography
Medical Physics, 2016Co-Authors: Logan Hubbard, Shant Malkasian, Brian Dertli, B. P. Ziemer, Jerry Lipinski, Bahman Sadeghi, H. Javan, Elliott M. Groves, Sabee MolloiAbstract:Purpose: To evaluate the accuracy of a patient-specific coronary perfusion territory assignment algorithm that uses CT angiography (CTA) and a Minimum-Cost-Path approach to assign coronary perfusion territories on a voxel-by-voxel basis for determination of myocardial mass at risk. Methods: Intravenous (IV) contrast (370 mg/mL iodine, 25 mL, 7 mL/s) was injected centrally into five swine (35–45 kg) and CTA was performed using a 320-slice CT scanner at 100 kVp and 200 mA. Additionally, a 4F catheter was advanced into the left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA) and contrast (30 mg/mL iodine, 10 mL, 1.5 mL/s) was directly injected into each coronary artery for isolation of reference coronary perfusion territories. Semiautomatic myocardial segmentation of the CTA data was then performed and the centerlines of the LAD, LCX, and RCA were digitally extracted through image processing. Individual coronary perfusion territories were then assigned using a Minimum-Cost-Path approach, and were quantitatively compared to the reference coronary perfusion territories. Results: The results of the coronary perfusion territory assignment algorithm were in good agreement with the reference coronary perfusion territories. The average volumetric assignment error from mitral orifice to apex was 5.5 ± 1.1%, corresponding to 2.1 ± 0.7 grams of myocardial mass misassigned for each coronary perfusion territory. Conclusion: The results indicate that accurate coronary perfusion territory assignment is possible on a voxel-by-voxel basis using CTA data and an assignment algorithm based on a Minimum-Cost-Path approach. Thus, the technique can potentially be used to accurately determine patient-specific myocardial mass at risk distal to a coronary stenosis, improving coronary lesion assessment and treatment. Conflict of Interest (only if applicable): Grant funding from Toshiba America Medical Systems.
Logan Hubbard - One of the best experts on this subject based on the ideXlab platform.
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Vessel-specific coronary perfusion territories using a CT angiogram with a Minimum Cost Path technique and its direct comparison to the American Heart Association 17-segment model
European radiology, 2020Co-Authors: Shant Malkasian, Logan Hubbard, Pablo Abbona, Brian Dertli, Jungnam Kwon, Sabee MolloiAbstract:This study compared the accuracy of an automated, vessel-specific Minimum Cost Path (MCP) myocardial perfusion territory assignment technique as compared with the standard American Heart Association 17-segment (AHA) model. Six swine (42 ± 9 kg) were used to evaluate the accuracy of the MCP technique and the AHA method. In each swine, a dynamic acquisition, comprised of twenty consecutive whole heart volume scans, was acquired with a computed tomography scanner, following peripheral injection of contrast material. From this acquisition, MCP and AHA perfusion territories were determined, for the left (LCA) and right (RCA) coronary arteries. Each animal underwent additional dynamic acquisitions, consisting of twenty consecutive volume scans, following direct intracoronary contrast injection into the LCA or RCA. These images were used as the reference standard (REF) LCA and RCA perfusion territories. The MCP and AHA techniques’ perfusion territories were then quantitatively compared with the REF perfusion territories. The myocardial mass of MCP perfusion territories (MMCP) was related to the mass of reference standard perfusion territories (MREF) by MMCP = 0.99MREF + 0.39 g (r = 1.00; R2 = 1.00). The mass of AHA perfusion territories (MAHA) was related to MREF by MAHA = 0.81MREF + 5.03 g (r = 0.99; R2 = 0.98). The vessel-specific MCP myocardial perfusion territory assignment technique more accurately quantifies LCA and RCA perfusion territories as compared with the current standard AHA 17-segment model. Therefore, it can potentially provide a more comprehensive and patient-specific evaluation of coronary artery disease. • The Minimum Cost Path (MCP) technique accurately determines left and right coronary artery perfusion territories, as compared with the American Heart Association 17-segment (AHA) model. • The Minimum Cost Path (MCP) technique could be applied to cardiac computed-tomography angiography images to accurately determine patient-specific left and right coronary artery perfusion territories. • The American Heart Association 17-segment (AHA) model often fails to accurately determine left and right coronary artery perfusion territories, especially in the inferior and inferoseptal walls of the left ventricular myocardium.
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Quantification of vessel-specific coronary perfusion territories using Minimum-Cost Path assignment and computed tomography angiography: Validation in a swine model.
Journal of cardiovascular computed tomography, 2018Co-Authors: Shant Malkasian, Logan Hubbard, Brian Dertli, Jungnam Kwon, Sabee MolloiAbstract:Abstract Background As combined morphological and physiological assessment of coronary artery disease (CAD) is necessary to reliably resolve CAD severity, the objective of this study was to validate an automated Minimum-Cost Path assignment (MCP) technique which enables accurate, vessel-specific assignment of the left (LCA) and right (RCA) coronary perfusion territories using computed tomography (CT) angiography data for both left and right ventricles. Methods Six swine were used to validate the MCP technique. In each swine, a dynamic acquisition comprised of twenty consecutive volume scans was acquired with a 320-slice CT scanner following peripheral injection of contrast material. From this acquisition the MCP technique was used to automatically assign LCA and RCA perfusion territories for the left and right ventricles, independently. Each animal underwent another dynamic CT acquisition following direct injection of contrast material into the LCA or RCA. Using this acquisition, reference standard LCA and RCA perfusion territories were isolated from the myocardial blush. The accuracy of the MCP technique was evaluated by quantitatively comparing the MCP-derived LCA and RCA perfusion territories to these reference standard territories. Results All MCP perfusion territory masses (MassMCP) and all reference standard perfusion territory masses (MassRS) in the left ventricle were related by MassMCP = 0.99MassRS+0.35 g (r = 1.00). MassMCP and MassRS in the right ventricle were related by MassMCP = 0.94MassRS+0.39 g (r = 0.96). Conclusion The MCP technique was validated in a swine animal model and has the potential to be used for accurate, vessel-specific assignment of LCA and RCA perfusion territories in both the left and right ventricular myocardium using CT angiography data.
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TH-CD-206-07: Determination of Patient-Specific Myocardial Mass at Risk Using Computed Tomography Angiography
Medical Physics, 2016Co-Authors: Logan Hubbard, Shant Malkasian, Brian Dertli, B. P. Ziemer, Jerry Lipinski, Bahman Sadeghi, H. Javan, Elliott M. Groves, Sabee MolloiAbstract:Purpose: To evaluate the accuracy of a patient-specific coronary perfusion territory assignment algorithm that uses CT angiography (CTA) and a Minimum-Cost-Path approach to assign coronary perfusion territories on a voxel-by-voxel basis for determination of myocardial mass at risk. Methods: Intravenous (IV) contrast (370 mg/mL iodine, 25 mL, 7 mL/s) was injected centrally into five swine (35–45 kg) and CTA was performed using a 320-slice CT scanner at 100 kVp and 200 mA. Additionally, a 4F catheter was advanced into the left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA) and contrast (30 mg/mL iodine, 10 mL, 1.5 mL/s) was directly injected into each coronary artery for isolation of reference coronary perfusion territories. Semiautomatic myocardial segmentation of the CTA data was then performed and the centerlines of the LAD, LCX, and RCA were digitally extracted through image processing. Individual coronary perfusion territories were then assigned using a Minimum-Cost-Path approach, and were quantitatively compared to the reference coronary perfusion territories. Results: The results of the coronary perfusion territory assignment algorithm were in good agreement with the reference coronary perfusion territories. The average volumetric assignment error from mitral orifice to apex was 5.5 ± 1.1%, corresponding to 2.1 ± 0.7 grams of myocardial mass misassigned for each coronary perfusion territory. Conclusion: The results indicate that accurate coronary perfusion territory assignment is possible on a voxel-by-voxel basis using CTA data and an assignment algorithm based on a Minimum-Cost-Path approach. Thus, the technique can potentially be used to accurately determine patient-specific myocardial mass at risk distal to a coronary stenosis, improving coronary lesion assessment and treatment. Conflict of Interest (only if applicable): Grant funding from Toshiba America Medical Systems.
Brian Dertli - One of the best experts on this subject based on the ideXlab platform.
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Vessel-specific coronary perfusion territories using a CT angiogram with a Minimum Cost Path technique and its direct comparison to the American Heart Association 17-segment model
European radiology, 2020Co-Authors: Shant Malkasian, Logan Hubbard, Pablo Abbona, Brian Dertli, Jungnam Kwon, Sabee MolloiAbstract:This study compared the accuracy of an automated, vessel-specific Minimum Cost Path (MCP) myocardial perfusion territory assignment technique as compared with the standard American Heart Association 17-segment (AHA) model. Six swine (42 ± 9 kg) were used to evaluate the accuracy of the MCP technique and the AHA method. In each swine, a dynamic acquisition, comprised of twenty consecutive whole heart volume scans, was acquired with a computed tomography scanner, following peripheral injection of contrast material. From this acquisition, MCP and AHA perfusion territories were determined, for the left (LCA) and right (RCA) coronary arteries. Each animal underwent additional dynamic acquisitions, consisting of twenty consecutive volume scans, following direct intracoronary contrast injection into the LCA or RCA. These images were used as the reference standard (REF) LCA and RCA perfusion territories. The MCP and AHA techniques’ perfusion territories were then quantitatively compared with the REF perfusion territories. The myocardial mass of MCP perfusion territories (MMCP) was related to the mass of reference standard perfusion territories (MREF) by MMCP = 0.99MREF + 0.39 g (r = 1.00; R2 = 1.00). The mass of AHA perfusion territories (MAHA) was related to MREF by MAHA = 0.81MREF + 5.03 g (r = 0.99; R2 = 0.98). The vessel-specific MCP myocardial perfusion territory assignment technique more accurately quantifies LCA and RCA perfusion territories as compared with the current standard AHA 17-segment model. Therefore, it can potentially provide a more comprehensive and patient-specific evaluation of coronary artery disease. • The Minimum Cost Path (MCP) technique accurately determines left and right coronary artery perfusion territories, as compared with the American Heart Association 17-segment (AHA) model. • The Minimum Cost Path (MCP) technique could be applied to cardiac computed-tomography angiography images to accurately determine patient-specific left and right coronary artery perfusion territories. • The American Heart Association 17-segment (AHA) model often fails to accurately determine left and right coronary artery perfusion territories, especially in the inferior and inferoseptal walls of the left ventricular myocardium.
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Quantification of vessel-specific coronary perfusion territories using Minimum-Cost Path assignment and computed tomography angiography: Validation in a swine model.
Journal of cardiovascular computed tomography, 2018Co-Authors: Shant Malkasian, Logan Hubbard, Brian Dertli, Jungnam Kwon, Sabee MolloiAbstract:Abstract Background As combined morphological and physiological assessment of coronary artery disease (CAD) is necessary to reliably resolve CAD severity, the objective of this study was to validate an automated Minimum-Cost Path assignment (MCP) technique which enables accurate, vessel-specific assignment of the left (LCA) and right (RCA) coronary perfusion territories using computed tomography (CT) angiography data for both left and right ventricles. Methods Six swine were used to validate the MCP technique. In each swine, a dynamic acquisition comprised of twenty consecutive volume scans was acquired with a 320-slice CT scanner following peripheral injection of contrast material. From this acquisition the MCP technique was used to automatically assign LCA and RCA perfusion territories for the left and right ventricles, independently. Each animal underwent another dynamic CT acquisition following direct injection of contrast material into the LCA or RCA. Using this acquisition, reference standard LCA and RCA perfusion territories were isolated from the myocardial blush. The accuracy of the MCP technique was evaluated by quantitatively comparing the MCP-derived LCA and RCA perfusion territories to these reference standard territories. Results All MCP perfusion territory masses (MassMCP) and all reference standard perfusion territory masses (MassRS) in the left ventricle were related by MassMCP = 0.99MassRS+0.35 g (r = 1.00). MassMCP and MassRS in the right ventricle were related by MassMCP = 0.94MassRS+0.39 g (r = 0.96). Conclusion The MCP technique was validated in a swine animal model and has the potential to be used for accurate, vessel-specific assignment of LCA and RCA perfusion territories in both the left and right ventricular myocardium using CT angiography data.
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TH-CD-206-07: Determination of Patient-Specific Myocardial Mass at Risk Using Computed Tomography Angiography
Medical Physics, 2016Co-Authors: Logan Hubbard, Shant Malkasian, Brian Dertli, B. P. Ziemer, Jerry Lipinski, Bahman Sadeghi, H. Javan, Elliott M. Groves, Sabee MolloiAbstract:Purpose: To evaluate the accuracy of a patient-specific coronary perfusion territory assignment algorithm that uses CT angiography (CTA) and a Minimum-Cost-Path approach to assign coronary perfusion territories on a voxel-by-voxel basis for determination of myocardial mass at risk. Methods: Intravenous (IV) contrast (370 mg/mL iodine, 25 mL, 7 mL/s) was injected centrally into five swine (35–45 kg) and CTA was performed using a 320-slice CT scanner at 100 kVp and 200 mA. Additionally, a 4F catheter was advanced into the left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA) and contrast (30 mg/mL iodine, 10 mL, 1.5 mL/s) was directly injected into each coronary artery for isolation of reference coronary perfusion territories. Semiautomatic myocardial segmentation of the CTA data was then performed and the centerlines of the LAD, LCX, and RCA were digitally extracted through image processing. Individual coronary perfusion territories were then assigned using a Minimum-Cost-Path approach, and were quantitatively compared to the reference coronary perfusion territories. Results: The results of the coronary perfusion territory assignment algorithm were in good agreement with the reference coronary perfusion territories. The average volumetric assignment error from mitral orifice to apex was 5.5 ± 1.1%, corresponding to 2.1 ± 0.7 grams of myocardial mass misassigned for each coronary perfusion territory. Conclusion: The results indicate that accurate coronary perfusion territory assignment is possible on a voxel-by-voxel basis using CTA data and an assignment algorithm based on a Minimum-Cost-Path approach. Thus, the technique can potentially be used to accurately determine patient-specific myocardial mass at risk distal to a coronary stenosis, improving coronary lesion assessment and treatment. Conflict of Interest (only if applicable): Grant funding from Toshiba America Medical Systems.
