Valve disease

2018 ◽  
pp. 443-459
Author(s):  
Joao Cavalcante ◽  
Florian von Knobelsdorff ◽  
Saul Myerson
Keyword(s):  
Cardiac Magnetic Resonance ◽  
Imaging Modality ◽  
Pulmonary Arteries ◽  
Three Dimensional ◽  
Large Field ◽  
Post Processing ◽  
Differential Flow ◽  
Precise Quantification ◽  
Left And Right ◽  
Cardiac Shunt

Although echocardiography remains the primary imaging modality for valvular heart disease (VHD) diagnosis, cardiac magnetic resonance (CMR) has gained much interest in this field over the last few years. CMR allows for three-dimensional imaging of the cardiovascular system, using a large field of view, and reconstruction in any given plane. Its capability to quantify flow allows for accurate measurement of regurgitation, cardiac shunt volumes/ratios, and differential flow volumes (e.g. left and right pulmonary arteries). In addition, CMR provides insights into the aetiology/mechanism of VHD, the precise quantification of VHD severity, and the evaluation of myocardial response (function, remodelling, and fibrosis). This chapter discusses several CMR techniques for evaluation of patients with VHD. Important tips and pitfalls in the image acquisition and post-processing analysis will be also discussed, providing the users the necessary framework for its clinical application.

scholarly journals Usefulness of three-dimensional echocardiography for assessment of left and right ventricular volumes in children, verified by cardiac magnetic resonance. Can we overcome the discrepancy?

2021 ◽  
Vol 17 (1) ◽  
pp. 71-83
Author(s):  
Halszka Kamińska ◽  
Łukasz A. Małek ◽  
Marzena Barczuk-Falęcka ◽  
Bożena Werner
Keyword(s):  
Cardiac Magnetic Resonance ◽  
Right Ventricular ◽  
Three Dimensional ◽  
Left Ventricular ◽  
Ventricular Volumes ◽  
3D Echo ◽  
Left And Right ◽  
Dimensional Echocardiography ◽  
Three Dimensional Echocardiography ◽  
The Right

IntroductionThe role of three-dimensional echocardiography (3D-ECHO) chamber quantification in children is still underestimated.Material and methodsIn 43 children 3D-ECHO measurements of end-diastolic (EDV) and end-systolic ventricular volumes (ESV) were compared to cardiac magnetic resonance (CMR) using Bland-Altman analysis and linear regression. The values of left and right ventricular volumes calculated in 3D-ECHO were compared with each other and verified by CMR.ResultsThe values of LV-EDV and LV-ESV measured in 3D-ECHO showed highly significant correlations with CMR (for LV-EDV r = 0.892, p < 0.00001; for LV-ESV r = 0.896, p < 0.00001). In the case of the right ventricle the correlation of 3D-ECHO results with CMR was still high (RV-EDV r = 0.848, p < 0.00001, RV-ESV r = 0.914, p < 0.00001), although mean RV-EDV and RV-ESV in 3D-ECHO were underestimated compared to CMR (by 38% for RV-EDV and 45% for RV-ESV). Correction of 3D-ECHO results using the coefficient of 1.38 and 1.45 for RV-EDV and RV-ESV, respectively, significantly improved the consistency of the results with CMR. 3D-ECHO offered lower mean values of right ventricular volumes compared to the left ventricle. The discrepancy was again reduced by the calculated coefficients.Conclusions3D-ECHO is a valuable tool for assessment of left ventricular volume, which strongly correlates and agrees with CMR. The right ventricular volumes calculated in 3D-ECHO tend to be significantly underestimated in comparison to CMR and corresponding left ventricular volumes obtained from 3D-ECHO. The use of coefficients developed by the study improves the consistency of right ventricular volumes measured by 3D-ECHO with results obtained by CMR and reduces the volumetric discrepancy between ventricles in 3D-ECHO.

scholarly journals Incidental Extracardiac Findings and Their Characterization on Cardiac MRI

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Matteo Gravina ◽  
Luca Pio Stoppino ◽  
Grazia Casavecchia ◽  
Angelo Pio Moffa ◽  
Roberta Vinci ◽  
...  
Keyword(s):  
Cardiac Magnetic Resonance ◽  
Magnetic Resonance ◽  
Imaging Modality ◽  
Correct Diagnosis ◽  
University Hospital ◽  
Large Field ◽  
Resonance Imaging ◽  
Number Of Patients ◽  
Noninvasive Imaging Modality ◽  
Clinically Significant

Background. Cardiac magnetic resonance imaging (cMRI) has recently emerged as a new noninvasive imaging modality that offers superior structural and functional assessment of the heart. cMRI benefits from a large field of view but, consequently, may capture incidental extracardiac findings (IEFs). We aimed to evaluate the frequency and significance of IEFs reported from clinically indicated cMRI scans. Methods. 742 consecutive patients (402 males and 340 females) referred to the Cardiac Magnetic Resonance Center of our University Hospital between January 2015 and December 2016 for clinically indicated cMRI were retrospectively enrolled for the evaluation of IEF prevalence and relevance. The median age of the subjects was 51 years (range: 5–85 years). Results. A significant number of patients who underwent cMRI had incidental and clinically significant IEFs (2% of the population, 11.4% of cases). cMRI allowed a correct diagnosis in 116/131 cases with a diagnostic accuracy value of 88.5%. Conclusions. IEFs on cMRI are not uncommon and lesions with mild or no clinical significance represent the most frequent findings. cMRI can characterize incidental findings with high accuracy in most cases.

Hemodynamic Investigation of Normal Developing Aortic Arch in the Chick Embryo

2008 ◽  
Author(s):  
Yajuan Wang ◽  
Onur Dur ◽  
Michael J. Patrick ◽  
Joseph P. Tinney ◽  
Kimimasa Tobita ◽  
...  
Keyword(s):  
Aortic Arch ◽  
Cardiac Development ◽  
Research Effort ◽  
Ductus Arteriosus ◽  
Pulmonary Arteries ◽  
Three Dimensional ◽  
Genetic Determinants ◽  
Morphological Studies ◽  
Left And Right ◽  
Aortic Arches

Governed by genetic and epigenetic feedback [1], during embryonic cardiac development, the anatomy of aortic arches demonstrates drastic three dimensional (3D) changes that interact with the function of cardiovascular system. Six major pairs of aortic arches appear at different embryonic periods and eventually form the two brachiocephalic arteries (left and right third), an aortic arch (left fourth) and pulmonary arteries and ductus arteriosus (left and right sixth) [2–4], Fig 1. Flow-driven hemodynamic loading plays a major role in this dynamic process. Morphological studies on the embryonic aortic arches began over 100 years ago while the recent remarkable developments include understanding genetic determinants such as the effects of neural crest cells [5,6]. However the relationship between hemodynamic factors and the dynamic 3D geometry changes is still limited requiring an interdisciplinary research effort [7,8].

The three-dimensional structure of frozen-hydrated left- and right-handed forms of bacterial flagellar filaments from an identical serotype

1986 ◽  
Vol 44 ◽  
pp. 298-299
Author(s):  
S. Trachtenberg ◽  
D. J. DeRosier
Keyword(s):  
Ionic Strength ◽  
Basal Body ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Protein Species ◽  
Liquid Environment ◽  
Bacterial Flagellum ◽  
Left And Right ◽  
Rotary Motor ◽  
Helical Parameters

The bacterial cell is propelled through the liquid environment by means of one or more rotating flagella. The bacterial flagellum is composed of a basal body (rotary motor), hook (universal coupler), and filament (propellor). The filament is a rigid helical assembly of only one protein species — flagellin. The filament can adopt different morphologies and change, reversibly, its helical parameters (pitch and hand) as a function of mechanical stress and chemical changes (pH, ionic strength) in the environment.

scholarly journals Three-dimensional in situ morphometrics of Mycobacterium tuberculosis infection within lesions by optical mesoscopy and novel acid-fast staining

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Robert J. Francis ◽  
Gillian Robb ◽  
Lee McCann ◽  
Bhagwati Khatri ◽  
James Keeble ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Three Dimensional ◽  
Large Field ◽  
Staining Procedure ◽  
3D Analysis ◽  
Mycobacterium Tuberculosis Infection ◽  
In Vivo Models ◽  
Novel Approach

AbstractTuberculosis (TB) preclinical testing relies on in vivo models including the mouse aerosol challenge model. The only method of determining colony morphometrics of TB infection in a tissue in situ is two-dimensional (2D) histopathology. 2D measurements consider heterogeneity within a single observable section but not above and below, which could contain critical information. Here we describe a novel approach, using optical clearing and a novel staining procedure with confocal microscopy and mesoscopy, for three-dimensional (3D) measurement of TB infection within lesions at sub-cellular resolution over a large field of view. We show TB morphometrics can be determined within lesion pathology, and differences in infection with different strains of Mycobacterium tuberculosis. Mesoscopy combined with the novel CUBIC Acid-Fast (CAF) staining procedure enables a quantitative approach to measure TB infection and allows 3D analysis of infection, providing a framework which could be used in the analysis of TB infection in situ.

Effect of post‐processing treatments on the quality of three‐dimensional printed rice starch constructs

2021 ◽  
Author(s):  
Radhika Theagarajan ◽  
Shubham Nimbkar ◽  
Jeyan Arthur Moses ◽  
Chinnaswamy Anandharamakrishnan
Keyword(s):  
Three Dimensional ◽  
Rice Starch ◽  
Post Processing

scholarly journals Rapid imaging of special nuclear materials for nuclear nonproliferation and terrorism prevention

2021 ◽  
Vol 7 (21) ◽  
pp. eabg3032
Author(s):  
Jana Petrović ◽  
Alf Göök ◽  
Bo Cederwall
Keyword(s):  
Nuclear Physics ◽  
Imaging Modality ◽  
Three Dimensional ◽  
Nuclear Fission ◽  
Machine Learning Techniques ◽  
Nuclear Materials ◽  
Prototype System ◽  
Fast Time ◽  
Gamma Emission ◽  
Special Nuclear Materials

We introduce a neutron-gamma emission tomography (NGET) technique for rapid detection, three-dimensional imaging, and characterization of special nuclear materials like weapons-grade plutonium and uranium. The technique is adapted from fundamental nuclear physics research and represents a previously unexplored approach to the detection and imaging of small quantities of these materials. The method is demonstrated on a radiation portal monitor prototype system based on fast organic scintillators, measuring the characteristic fast time and energy correlations between particles emitted in nuclear fission processes. The use of these correlations in real time in conjunction with modern machine learning techniques provides unprecedented imaging efficiency and high spatial resolution. This imaging modality addresses global security threats from terrorism and the proliferation of nuclear weapons. It also provides enhanced capabilities for addressing different nuclear accident scenarios and for environmental radiological surveying.

scholarly journals On the Post-Processing of 3D-Printed ABS Parts

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1559
Author(s):  
Mohammad Reza Khosravani ◽  
Jonas Schüürmann ◽  
Filippo Berto ◽  
Tamara Reinicke
Keyword(s):  
Surface Treatment ◽  
Fused Deposition Modeling ◽  
Three Dimensional ◽  
Acrylonitrile Butadiene Styrene ◽  
Experimental Tests ◽  
Fracture Load ◽  
Post Processing ◽  
Fused Deposition ◽  
Dog Bone ◽  
3D Printed

Application of Additive Manufacturing (AM) has significantly increased in the past few years. AM also known as three-dimensional (3D) printing has been currently used in fabrication of prototypes and end-use products. Considering the new applications of additively manufactured components, it is necessary to study structural details of these parts. In the current study, influence of a post-processing on the mechanical properties of 3D-printed parts has been investigated. To this aim, Acrylonitrile Butadiene Styrene (ABS) material was used to produce test coupons based on the Fused Deposition Modeling (FDM) process. More in deep, a device was designed and fabricated to fix imperfection and provide smooth surfaces on the 3D-printed ABS specimens. Later, original and treated specimens were subjected to a series of tensile loads, three-point bending tests, and water absorption tests. The experimental tests indicated fracture load in untreated dog-bone shaped specimen was 2026.1 N which was decreased to 1951.7 N after surface treatment. Moreover, the performed surface treatment was lead and decrease in tensile strength from 29.37 MPa to 26.25 MPa. Comparison of the results confirmed effects of the surface modification on the fracture toughness of the examined semi-circular bending components. Moreover, a 3D laser microscope was used for visual investigation of the specimens. The documented results are beneficial for next designs and optimization of finishing processes.

scholarly journals Magnetic particle imaging of particle dynamics in complex matrix systems

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Sebastian Draack ◽  
Meinhard Schilling ◽  
Thilo Viereck
Keyword(s):  
Magnetic Particle ◽  
Imaging Modality ◽  
Three Dimensional ◽  
Local Environment ◽  
Relaxation Mechanism ◽  
Harmonic Spectrum ◽  
Magnetic Particle Imaging ◽  
Matrix Interactions ◽  
Tracer Distribution ◽  
Particle Imaging

Abstract Magnetic particle imaging (MPI) is a young imaging modality for biomedical applications. It uses magnetic nanoparticles as a tracer material to produce three-dimensional images of the spatial tracer distribution in the field-of-view. Since the tracer magnetization dynamics are tied to the hydrodynamic mobility via the Brownian relaxation mechanism, MPI is also capable of mapping the local environment during the imaging process. Since the influence of viscosity or temperature on the harmonic spectrum is very complicated, we used magnetic particle spectroscopy (MPS) as an integral measurement technique to investigate the relationships. We studied MPS spectra as function of both viscosity and temperature on model particle systems. With multispectral MPS, we also developed an empirical tool for treating more complex scenarios via a calibration approach. We demonstrate that MPS/MPI are powerful methods for studying particle-matrix interactions in complex media.

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