“The Starry Sky.” A new intraprocedural three‐dimensional echocardiographic technique

2019 ◽  
Vol 36 (9) ◽  
pp. 1765-1768
Author(s):  
Alessandro Vairo ◽  
Matteo Marro ◽  
Giovanni Speziali ◽  
Mauro Rinaldi ◽  
Stefano Salizzoni
Author(s):  
Luigi P. Badano ◽  
Roberto M. Lang ◽  
Alexandra Goncalves

The advent of fully-sampled matrix array transthoracic transducers has enabled advanced digital processing and improved image formation algorithms and brought three-dimensional echocardiography (3DE) technology into clinical practice. Currently, 3DE is recognized as an important echocardiographic technique, demonstrated to be superior to two-dimensional echocardiography in various clinical scenarios. This chapter focuses on the technology of 3DE matrix transducers, physics of 3D imaging, data set acquisition (multiplane, real-time, full-volume, zoom, and colour), and display (volume rendering, surface rendering and multislice) modalities. The chapter also addresses the issues of training in 3DE, and main clinical indications and reporting of transthoracic and transoesophageal 3DE.


2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
A Vairo ◽  
M Marro ◽  
G Speziali ◽  
M Rinaldi ◽  
S Salizzoni

Abstract BACKGROUND Mitral valve repair is the preferred surgical treatment for severe mitral regurgitation due to degenerative leaflet prolapse. Within the growing era of transcatheter treatments for valvular heart disease, an innovative micro-invasive trans-ventricular beating-heart procedure was developed. Three-dimensional transoesophageal echocardiographic guidance is crucial to assist the operator in instrument navigation and chords positioning. Indeed, it is important an equidistant chords placement on the leaflet to ensure a uniform force distribution on the prolapsing segment and to avoid damaging of the previously inserted chords. PURPOSE To propose an intraoperative three-dimensional echocardiographic technique that allows operators to see the exact location of the polytetrafluoroethylene (ePTFE) chords used for the mitral repair. METHODS The procedure is performed using a device that is introduced through a posterolateral ventriculotomy and it is advanced towards the mitral valve under real-time 3D transoesophageal guidance. The prolapsing segments are grasped with the jaw of the instrument and the chords are implanted to achieve the proper distribution of forces and then tensioned and secured outside the ventricle. The proposed technique exploits the greater echogenicity of the artificial chord loop compared to native chords and leaflets. By lowering of the gains, remaining in the three-dimensional mitral valve surgical view, the signals of the native structures are attenuated, the underlying ventricular cavity appears black and the insertion points are visible as an intense signal on the virtual free edge of the leaflet treated. Figure 1 shows the intraoperative sequence of images of a case performed at our centre. The images were acquired using real time single beat three-dimensional reconstruction. Figure 1A shows the surgical view of the native valve with prolapse of the P2-P3 scallops. Image 1B reveals the prolapsing leaflet grasping and device location. After gain lowering, it’s possible to see the intense signal of the positioned artificial chord (Figure 1C). It can also be noted how this position matches with the position of the device at the time of grasping. Image 1D shows the partial disappearance of the prolapse during the tensioning test after the positioning of a second chord in a more medial position. Figure 1E shows the correct position of the ePTFE chords. We can notice the second chord placed in a medial position from the first one. This view, with dark ventricular chamber and intense signals of chordae loops, looks like a "STARRY SKY". RESULTS This technique allows to locate the correct insertion points of the artificial chords during the procedure. CONCLUSIONS This is a simple technique to guide operators during trans-ventricular beating heart mitral valve repair with ePTFE chords. Abstract P951 Figure 1


1966 ◽  
Vol 25 ◽  
pp. 227-229 ◽  
Author(s):  
D. Brouwer

The paper presents a summary of the results obtained by C. J. Cohen and E. C. Hubbard, who established by numerical integration that a resonance relation exists between the orbits of Neptune and Pluto. The problem may be explored further by approximating the motion of Pluto by that of a particle with negligible mass in the three-dimensional (circular) restricted problem. The mass of Pluto and the eccentricity of Neptune's orbit are ignored in this approximation. Significant features of the problem appear to be the presence of two critical arguments and the possibility that the orbit may be related to a periodic orbit of the third kind.


Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.


Author(s):  
P.L. Moore

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.


Sign in / Sign up

Export Citation Format

Share Document