scholarly journals Bayesian Estimation of Geometric Morphometric Landmarks for Simultaneous Localization of Multiple Anatomies in Cardiac CT Images

Entropy ◽  
2021 ◽  
Vol 23 (1) ◽  
pp. 64
Author(s):  
Byunghwan Jeon ◽  
Sunghee Jung ◽  
Hackjoon Shim ◽  
Hyuk-Jae Chang
Keyword(s):  
Cross Sections ◽  
Cardiac Computed Tomography ◽  
Pulmonary Veins ◽  
Three Dimensional ◽  
Target Object ◽  
Multiple Objects ◽  
Geometric Morphometric ◽  
Cardiac Computed Tomography Angiography ◽  
Cardiac Cta ◽  
New Feature

We propose a robust method to simultaneously localize multiple objects in cardiac computed tomography angiography (CTA) images. The relative prior distributions of the multiple objects in the three-dimensional (3D) space can be obtained through integrating the geometric morphological relationship of each target object to some reference objects. In cardiac CTA images, the cross-sections of ascending and descending aorta can play the role of the reference objects. We employed the maximum a posteriori (MAP) estimator that utilizes anatomic prior knowledge to address this problem of localizing multiple objects. We propose a new feature for each pixel using the relative distances, which can define any objects that have unclear boundaries. Our experimental results targeting four pulmonary veins (PVs) and the left atrial appendage (LAA) in cardiac CTA images demonstrate the robustness of the proposed method. The method could also be extended to localize other multiple objects in different applications.

scholarly journals Coronary Centerline Extraction from CCTA Using 3D-UNet

2021 ◽  
Vol 13 (4) ◽  
pp. 101
Author(s):  
Alexandru Dorobanțiu ◽  
Valentin Ogrean ◽  
Remus Brad
Keyword(s):  
Computed Tomography ◽  
Cardiac Computed Tomography ◽  
Three Dimensional ◽  
Class Imbalance ◽  
Training Data ◽  
Cardiac Computed Tomography Angiography ◽  
Centerline Extraction ◽  
Network Training ◽  
Dimensional Reconstruction ◽  
Coronary Centerline

The mesh-type coronary model, obtained from three-dimensional reconstruction using the sequence of images produced by computed tomography (CT), can be used to obtain useful diagnostic information, such as extracting the projection of the lumen (planar development along an artery). In this paper, we have focused on automated coronary centerline extraction from cardiac computed tomography angiography (CCTA) proposing a 3D version of U-Net architecture, trained with a novel loss function and with augmented patches. We have obtained promising results for accuracy (between 90–95%) and overlap (between 90–94%) with various network training configurations on the data from the Rotterdam Coronary Artery Centerline Extraction benchmark. We have also demonstrated the ability of the proposed network to learn despite the huge class imbalance and sparse annotation present in the training data.

Progressive Surface Reconstruction of Cardiac Anatomy from Sparse and Scattered Points for Heart Mapping Procedure

2020 ◽  
Vol 10 (11) ◽  
pp. 2564-2576
Author(s):  
Yifan Fu ◽  
Rao Fu ◽  
Jing Wang ◽  
Yirong Liu ◽  
Jian Wu
Keyword(s):  
Surface Reconstruction ◽  
Cardiac Computed Tomography ◽  
Three Dimensional ◽  
Reconstruction Algorithm ◽  
Linear Increase ◽  
Mapping Procedure ◽  
Cardiac Computed Tomography Angiography ◽  
Grid Model ◽  
Search Criterion ◽  
Partition Method

In computer aided radiofrequency catheter ablation of the heart, intraoperative three-dimensional reconstruction of the intracardiac cavity is a very important step. In this paper, we propose a point-by-point surface reconstruction algorithm based on scattered points and guarantee the properties of local reconstruction and surface smoothing. The algorithm firstly builds a generic self-adapted grid model to enclose and approximate to the initial sampled points (at least four points) captured from endocardial surface. Then, the grid model is deformed when adding a newly sampled point. To avoid the linear increase of computation with the increasing of the number of points and unbalanced neighborhood, we propose a local region search criterion based on orthogonal least squares and a neighborhood partition method. Such criterion can guarantee selecting the minimum local balanced points to complete each step of grid deformation. Four normal and six abnormal cardiac computed tomography angiography models specific to the left atrium are used to verify our method. The results show that the surface reconstruction errors as well as the reconstruction time per update are smaller than the state-of-theart methods applied to progressive reconstruction using sparse and scattered points. Furthermore, a cardiac phantom of right ventricle is used to verify the 3D surface reconstruction by our method. The experimental results confirm the feasibility of the proposed algorithm in practical operation.

scholarly journals Application of transesophageal echocardiography, left atrial appendage angiography, cardiac computed tomography angiography, and three-dimensional reconstruction model in left atrial appendage occlusion

2020 ◽  
Vol 16 (1) ◽  
pp. 155014771989595
Author(s):  
Huang Hao Lei ◽  
Li Hua Kang ◽  
Song Zhi Yuan ◽  
Wan Chen ◽  
Yao Qing
Keyword(s):  
Computed Tomography ◽  
Computed Tomography Angiography ◽  
Left Atrial ◽  
Left Atrial Appendage ◽  
Cardiac Computed Tomography ◽  
Three Dimensional ◽  
Atrial Appendage ◽  
Three Dimensional Reconstruction ◽  
Cardiac Computed Tomography Angiography ◽  
Dimensional Reconstruction

Objective: The objective was to evaluate the application of transesophageal echocardiography, left atrial appendage angiography, cardiac computed tomography angiography, and three-dimensional reconstruction model in the left atrial appendage occlusion. Methods: A total of 53 patients with persistent atrial fibrillation hospitalized from January 2015 to February 2019 were selected. Transesophageal echocardiography and cardiac computed tomography angiography were performed simultaneously before operation, and three-dimensional reconstruction of the left atrial appendage model was performed based on the cardiac computed tomography angiography findings. The morphology and size of the left atrial appendage were displayed by the left atrial appendage angiography during the operation. Results: Cardiac computed tomography angiography revealed filling defects in the left atrial appendage in four patients, whereas transesophageal echocardiography revealed thrombosis in two patients of the four patients. According to the cardiac computed tomography angiography results, the morphology of the left atrial appendage was classified into chicken wing–like, cauliflower-like, wind vane–like, and cactus-like. The diameters and depths of the left atrial appendage measured by cardiac computed tomography angiography and three-dimensional reconstruction model were found to be the greatest, and the orifice sizes and depths of the left atrial appendage measured by the left atrial appendage angiography were the smallest. Conclusion: Transesophageal echocardiography, left atrial appendage angiography, cardiac computed tomography angiography, and three-dimensional reconstruction model can evaluate the morphology and size of the left atrial appendage. The cardiac computed tomography angiography and three-dimensional reconstruction model could demonstrate the internal structure of the left atrial appendage more clearly.

Use of Three-dimensional Printing in the Development of Optimal Cardiac CT Scanning Protocols

2020 ◽  
Vol 16 (8) ◽  
pp. 967-977
Author(s):  
Zhonghua Sun
Keyword(s):  
Cardiovascular Disease ◽  
Cardiac Computed Tomography ◽  
Three Dimensional ◽  
Ct Scanning ◽  
Aortic Diseases ◽  
Clinical Value ◽  
Three Dimensional Printing ◽  
Doctor Patient Communication ◽  
Medical Education And Training ◽  
3D Printed

Three-dimensional (3D) printing is increasingly used in medical applications with most of the studies focusing on its applications in medical education and training, pre-surgical planning and simulation, and doctor-patient communication. An emerging area of utilising 3D printed models lies in the development of cardiac computed tomography (CT) protocols for visualisation and detection of cardiovascular disease. Specifically, 3D printed heart and cardiovascular models have shown potential value in the evaluation of coronary plaques and coronary stents, aortic diseases and detection of pulmonary embolism. This review article provides an overview of the clinical value of 3D printed models in these areas with regard to the development of optimal CT scanning protocols for both diagnostic evaluation of cardiovascular disease and reduction of radiation dose. The expected outcomes are to encourage further research towards this direction.

Geological Field Sketches and Illustrations

2019 ◽  
Author(s):  
Matthew J. Genge
Keyword(s):  
Cross Sections ◽  
Earth Science ◽  
Three Dimensional ◽  
Worked Examples ◽  
Scientific Publications ◽  
Thin Sections ◽  
Geological Features ◽  
Different Types ◽  
The Subject

Drawings, illustrations, and field sketches play an important role in Earth Science since they are used to record field observations, develop interpretations, and communicate results in reports and scientific publications. Drawing geology in the field furthermore facilitates observation and maximizes the value of fieldwork. Every geologist, whether a student, academic, professional, or amateur enthusiast, will benefit from the ability to draw geological features accurately. This book describes how and what to draw in geology. Essential drawing techniques, together with practical advice in creating high quality diagrams, are described the opening chapters. How to draw different types of geology, including faults, folds, metamorphic rocks, sedimentary rocks, igneous rocks, and fossils, are the subjects of separate chapters, and include descriptions of what are the important features to draw and describe. Different types of sketch, such as drawings of three-dimensional outcrops, landscapes, thin-sections, and hand-specimens of rocks, crystals, and minerals, are discussed. The methods used to create technical diagrams such as geological maps and cross-sections are also covered. Finally, modern techniques in the acquisition and recording of field data, including photogrammetry and aerial surveys, and digital methods of illustration, are the subject of the final chapter of the book. Throughout, worked examples of field sketches and illustrations are provided as well as descriptions of the common mistakes to be avoided.

scholarly journals Appropriate utilization of cardiac computed tomography for the assessment of stable coronary artery disease

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Michael Hammer ◽  
Muhtashim Mian ◽  
Levi Elhadad ◽  
Mary Li ◽  
Idan Roifman
Keyword(s):  
Computed Tomography ◽  
Coronary Artery Disease ◽  
Coronary Artery ◽  
Cardiac Imaging ◽  
Cardiac Computed Tomography ◽  
The United States ◽  
Appropriate Use ◽  
Potential Cost ◽  
Cardiac Computed Tomography Angiography ◽  
Artery Disease

Abstract Background Appropriate use criteria (AUC) have been developed in response to growth in cardiac imaging utilization and concern regarding associated costs. Cardiac computed tomography angiography (CCTA) has emerged as an important modality in the evaluation of coronary artery disease, however its appropriate utilization in actual practice is uncertain. Our objective was to determine the appropriate utilization of CCTA in a large quaternary care institution and to compare appropriate utilization pre and post publication of the 2013 AUC guidelines. We hypothesized that the proportion of appropriate CCTA utilization will be similar to those of other comparable cardiac imaging modalities and that there would be a significant increase in appropriate use post AUC publication. Methods We employed a retrospective cohort study design of 2577 consecutive patients undergoing CCTA between January 1, 2012 and December 30, 2016. An appropriateness category was assigned for each CCTA. Appropriateness classifications were compared pre- and post- AUC publication via the chi-square test. Results Overall, 83.5% of CCTAs were deemed to be appropriate based on the AUC. Before the AUC publication, 75.0% of CCTAs were classified as appropriate whereas after the AUC publication, 88.0% were classified as appropriate (p < 0.001). The increase in appropriate utilization, when extrapolated to the Medicare population of the United States, was associated with potential cost savings of approximately $57 million per year. Conclusions We report a high rate of appropriate use of CCTA and a significant increase in the proportion of CCTAs classified as appropriate after the AUC publication.

scholarly journals Fluid–structure interaction in a fully coupled three-dimensional mitral–atrium–pulmonary model

2021 ◽  
Author(s):  
Liuyang Feng ◽  
Hao Gao ◽  
Nan Qi ◽  
Mark Danton ◽  
Nicholas A. Hill ◽  
...  
Keyword(s):  
Mitral Valve ◽  
Left Atrium ◽  
Left Atrial ◽  
Left Atrial Appendage ◽  
Pulmonary Veins ◽  
Three Dimensional ◽  
Left Heart ◽  
Structure Interaction ◽  
Acute Mitral Regurgitation ◽  
Reversal Flow

AbstractThis paper aims to investigate detailed mechanical interactions between the pulmonary haemodynamics and left heart function in pathophysiological situations (e.g. atrial fibrillation and acute mitral regurgitation). This is achieved by developing a complex computational framework for a coupled pulmonary circulation, left atrium and mitral valve model. The left atrium and mitral valve are modelled with physiologically realistic three-dimensional geometries, fibre-reinforced hyperelastic materials and fluid–structure interaction, and the pulmonary vessels are modelled as one-dimensional network ended with structured trees, with specified vessel geometries and wall material properties. This new coupled model reveals some interesting results which could be of diagnostic values. For example, the wave propagation through the pulmonary vasculature can lead to different arrival times for the second systolic flow wave (S2 wave) among the pulmonary veins, forming vortex rings inside the left atrium. In the case of acute mitral regurgitation, the left atrium experiences an increased energy dissipation and pressure elevation. The pulmonary veins can experience increased wave intensities, reversal flow during systole and increased early-diastolic flow wave (D wave), which in turn causes an additional flow wave across the mitral valve (L wave), as well as a reversal flow at the left atrial appendage orifice. In the case of atrial fibrillation, we show that the loss of active contraction is associated with a slower flow inside the left atrial appendage and disappearances of the late-diastole atrial reversal wave (AR wave) and the first systolic wave (S1 wave) in pulmonary veins. The haemodynamic changes along the pulmonary vessel trees on different scales from microscopic vessels to the main pulmonary artery can all be captured in this model. The work promises a potential in quantifying disease progression and medical treatments of various pulmonary diseases such as the pulmonary hypertension due to a left heart dysfunction.

scholarly journals Geometric morphometric investigation of craniofacial morphological change in domesticated silver foxes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Timothy M. Kistner ◽  
Katherine D. Zink ◽  
Steven Worthington ◽  
Daniel E. Lieberman
Keyword(s):  
Three Dimensional ◽  
Cranial Base ◽  
Craniofacial Morphology ◽  
Wild Populations ◽  
Linear Measurements ◽  
Skeletal Morphology ◽  
Geometric Morphometric ◽  
Domestication Syndrome ◽  
Morphometric Investigation ◽  
Unselected Population

AbstractTo test the effects of domestication on craniofacial skeletal morphology, we used three-dimensional geometric morphometrics (GM) along with linear and endocranial measurements to compare selected (domesticated) and unselected foxes from the Russian Farm-Fox Experiment to wild foxes from the progenitor population from which the farmed foxes are derived. Contrary to previous findings, we find that domesticated and unselected foxes show minimal differences in craniofacial shape and size compared to the more substantial differences between the wild foxes and both populations of farmed foxes. GM analyses and linear measurements demonstrate that wild foxes differ from farmed foxes largely in terms of less cranial base flexion, relatively expanded cranial vaults, and increased endocranial volumes. These results challenge the assumption that the unselected population of foxes kept as part of the Russian Farm-Fox experiment are an appropriate proxy for ‘wild’ foxes in terms of craniofacial morphology and highlight the need to include wild populations in further studies of domestication syndrome to disentangle the phenotypic effects of multiple selection pressures. These findings also suggest that marked increases in docility cannot be reliably diagnosed from shape differences in craniofacial skeletal morphology.

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