WO2012168371A1 - Device three-dimensionally reproducing a fetal heart - Google Patents

Abstract

The invention relates to a device (1) three-dimensionally reproducing a fetal heart, characterized in that it is suitable for portraying at least two section planes, the first plane (P₁) corresponding to the fetal section of the four chambers, and the second plane (P₂) corresponding to the fetal section of the great vessels, and including at least two parts (10, 20): a first part (10) corresponding to a lower portion of the fetal heart, and having a substantially planar upper surface (11) corresponding to the first section plane (P₁); and a second part (20), having the shape of a dihedron, the apical angle of which is acute, and which has a substantially planar upper surface corresponding to the second section plane (P₂), the edge (24) of the dihedron forming said second part (20) being aligned with the straight line (D) extending from the intersection of the two section planes (P₁ and P₂).

Description

 DEVICE REPRODUCING A FETAL HEART INTO THREE

 DIMENSIONS

The invention relates generally to fetal echocardiography. More specifically, the invention relates to the screening of antenatal malformations of a fetal heart, as well as assistance in understanding cardiac anatomy for purposes of teaching fetal echocardiography.

For about twenty years, it is possible to detect antenatal malformations through the implementation of fetal ultrasounds.

 Ultrasound is an imaging technique that can be used to approach anatomical structures in the form of two-dimensional cutting planes. In 2005, the National Technical Committee for Prenatal Screening Ultrasound (CNTEDP) published recommendations on the content of any screening ultrasound, including an obligation for obstetricians to analyze the fetal heart according to two particular known plans. under the names of "cutting plan of the four cavities" and "cutting plan of large vessels", to detect malformations.

 The "four cavities" cutting plane (plane passing through the tip of the heart, the four cardiac cavities and near the superior pulmonary veins) allows us to study the harmony of the four cavities of the fetal heart, the axis of the heart fetal, myocardium, atrioventricular valves, atrioventricular concordance, and interventricular septum.

The cutting plane "large vessels" (plane that passes through the right atrium, right ventricle, pulmonary artery and cuts the aorta transversely to the center) allows him to study the appearance and position large vessels of the fetal heart. The evaluation of these large vessels increases the chances of detecting major cardiac malformations, including cono-truncal anomalies. The ultrasound of the fetal heart according to these cutting planes is however difficult to achieve, in particular according to the cutting plane of the large vessels. Thus, the observation of the fetal heart in the frontal (including the vertical axis and the large horizontal axis of the fetal heart), horizontal (including the large horizontal axis and the small horizontal axis of the fetal heart) and / or sagittal (including the vertical axis and the small horizontal axis of the fetal heart).

 Indeed, the heart is the most difficult organ to examine by ultrasound because of its complex three-dimensional anatomy and its perpetual motion, which differentiate it from all other organs.

 However, there is currently no real three-dimensional representation that allows obstetricians to visualize the fetal heart in its entirety. Ultrasound is indeed a two-dimensional representation of the fetal heart seen in section, and thus requires from the operator (the obstetrician) an interpretation and a mental reconstruction effort in three dimensions.

 In addition, the fetal heart differs from the adult heart in many ways, so that the use of an existing model of the adult heart is impossible.

Typically, the fetal heart does not include a foramen ovale between the right and left atria nor an arterial duct, and its ventricular geometry differs due to the equal ventricular pressures in the fetus.

 An object of the invention is therefore to provide a three-dimensional representation of a fetal heart that is simple to use and allows a good visualization of the cutting planes four cavities and large vessels, minimizing the number of parts to be made and their cost of manufacture, and can be used in particular for purposes of teaching fetal echocardiography to facilitate understanding of the fetal heart anatomy.

For this, the invention proposes a device reproducing a fetal heart in three dimensions, characterized in that it is adapted to display at least two cutting planes, the first plane Pi corresponding to the fetal cut "of the four cavities" and the second plane P ₂ corresponding to the fetal cut "large vessels", and comprising at least two pieces,

 a first part corresponding to a lower portion of the fetal heart, having a substantially flat upper face corresponding to the first section plane Pi, and

a second piece, having the shape of a dihedron whose angle at the apex is acute, and having a substantially flat upper surface corresponding to the second plane of section P ₂ , the edge of the dihedron forming said second piece being aligned with the right D from the section of the two section planes Pi and P ₂ .

 Some preferred but non-limiting aspects of the device according to the invention are the following:

 - It further comprises a third part corresponding to an upper part of the fetal heart, having a dihedral bottom surface whose apex angle is obtuse and adapted to be disposed on the first and the second part;

 the upper face of the first piece and the lower face of the second piece are of complementary shapes and are able to fit together;

 - It further comprises retaining means adapted to maintain the parts in position relative to each other;

 the retaining means are form-complementary means, in particular protuberances extending from one of the lower and upper faces of the parts and adapted to engage with cavities formed in the other of the corresponding lower and upper faces; ;

 the cavities correspond to cavities existing in the upper faces of the pieces;

 the retaining means are magnets;

- It is made of resin; and - The upper surface of the lower part is covered two-thirds by the central part.

 According to a second aspect, the invention proposes a method of manufacturing a device according to the invention, in which at least one of the parts is produced by injection-molding in a silicone mold.

Other characteristics, aims and advantages will appear better on reading the detailed description which follows, made with reference to the appended figures, given by way of non-limiting example and in which:

 - Figures 1A and 1B show an embodiment of a device according to the invention, seen from the side in two different orientations;

 FIG. 2 represents an exemplary embodiment of the lower part of the device of FIG. 1, seen from above,

 FIG. 3A represents an exemplary embodiment of the second part of the device of FIG. 1, viewed from above,

 FIG. 3B represents the second piece of FIG. 3A, seen from below,

 FIG. 4A represents an exemplary embodiment of the third piece of the device of FIG. 1, viewed from above, and

 FIG. 4B represents an exemplary embodiment of the third piece of the device of FIG. 1, viewed from below, and

 FIG. 5 shows the central part of FIGS. 3A and 3B assembled with the bottom part of FIG. 2. We will now describe a device 1 reproducing a three-dimensional fetal heart according to the present invention.

This device is a three-dimensional object adapted to be opened according to the two cutting planes imposed by the CNTEDP, namely the cutting plane "of the four cavities" Pi and the cutting plane "large vessels" P ₂ . It comprises at least one so-called lower part 10, corresponding to a first part (referred to as a lower part with reference to the arbitrary position of FIGS. 1A and 1B) of the fetal heart and having a substantially plane upper surface 1 1 corresponding to the plane of section of the four cavities Pi, and a central piece 20, having the shape of a dihedral, having a substantially planar upper surface 21 partially corresponding to the cutting plane "large vessels" P2.

 The lower piece 10 is a three-dimensional reproduction of the lower part of the fetal heart seen in section along the plane of the four cavities Pi. It therefore comprises a reproduction of the four cavities (right atrium 12, right ventricle 13, left atrium 14 and left ventricle 15), descending aorta 16, inferior vena cava 17, tricuspid valves 18 and mitral 19, etc. , as well as features of the fetal heart visible according to this sectional plane (in particular the foramen ovale F between the atria 12 and 14). The upper face 1 1 of this piece therefore corresponds to the ultrasound (two-dimensional) according to the cutting plane of the four cavities Pi.

 In this way, it is possible for an obstetrician to compare the echography according to the cutting plane of the four cavities Pi with the upper face 1 1 of the lower part 10 in order to possibly detect a malformation of the fetal heart. Device 1 can also be used as a visual aid for understanding cardiac anatomy for teaching purposes or to help patients understand a diagnosis.

The central piece 20 q uant to it is a partial reproduction of the three-dimensional fetal heart according to the cutting plane of the large vessels P2 on one side and the cutting plane of the four cavities Pi on the other side. It has the shape of a dihedron whose apex angle is acute (of the order of about 40 °), the upper surface 21 represents in section the arterial duct 22 and the aortic valve 23 of the fetal heart. Optionally, the lower surface 25 may represent in section the left atrium 14, the left ventricle 15 and the aortic valve 23. This central piece 20 does not, however, reproduce the entire section of the fetal heart along the cutting plane of the large vessels P ₂ , but stops at the intersection of this plane P ₂ with the cutting plane of the four Pi cavities. More specifically, when the central piece 20 is positioned on the lower piece 10, the edge 24 of the dihedral of the central piece 20 is aligned with the line D from the section of the two section planes Pi and P ₂ . In this position, the upper surface 1 1 of the lower part 10 is then covered about two thirds by the central part 20, so that a portion 1 1 bis of the lower part 10 remains visible despite the positioning of the central part 20 on this one. It follows that it is the assembly of the two parts 10 and 20 which provides an approximate representation of the entire fetal heart in the plane P ₂ , and not the central piece 20 alone.

The inventors have however determined that despite this approximation, the overall appearance of the two pieces 10, 20 thus assembled corresponds relatively reliably to the image of the fetal heart in the plane of section of the large vessels P ₂ . Indeed, the accuracy of the ultrasound (angle between the image obtained in reality by the obstetrician and the expected image according to the plane of large vessels P ₂ as defined by the CNTEDP) is of the order of 3 Generally at 5 °, and the visual rendering of the upper surface 1 1 not concealed by the central piece 20 is very similar to what would be observed if we reproduced the entire plane of the large vessels P ₂ .

The partial reproduction of this plane P ₂ by means of the central piece 20, extended by the undisclosed part of the lower piece 10, thus makes it possible to obtain a sufficiently reliable representation for the analysis of the ultrasound, while reducing the number of parts necessary for the realization of the device 1 and simplifying their mutual arrangement and their use, only two parts being indeed necessary (instead of three if the device 1 had been cut integrally along the plane of the large vessels P ₂ ) .

The device 1 may further comprise an upper part 30 adapted to complete the heart. This upper piece 30 then preferably a lower face 31 in the form of a dihedral having an obtuse apex angle (of the order of 140 °) complementary to the upper face 21 of the central piece 20 and the part 1 1 bis undisclosed of the upper face 1 1 of the lower part 10.

Furthermore, each of the parts 10, 20, 30 can further reproduce the external appearance of the fetal heart.

 Thus, the outer face of the lower part 10 (corresponding to the face opposite to its upper face 11) may have a generally convex shape from which tubes reproducing the appearance of a portion of pulmonary veins 26 protrude.

 The edge of the dihedral forming the central piece 20 as for el can also be convex and reproduce a lateral portion of the fetal heart, and in particular the lateral wall of the left atrium 14 and the left ventricle 15, as well as auricles and a pulmonary vein 26.

 Finally, the outer face 32 of the upper piece 30 (corresponding to the face opposite to its lower face 31) may have a generally convex shape reproducing in particular the appearance of the arterial duct 22 (whose presence is characteristic of the fetal heart), of the ascending aorta 33 as well as arteries 34 coming out of it, superior vena cava 35, auricles 36 and veins.

 In this way, when all the parts 1 0, 20, 30 of the device 1 are assembled, the device 1 is a three-dimensional reproduction of the fetal heart, to assist the obstetricians in the three-dimensional reconstruction of the heart from the two-dimensional images. obtained by ultrasound.

This three-dimensional reproduction thus helps to better understand the functioning of the fetal heart and to identify the differences between a fetal heart and an adult heart, especially during the training of scouting sonographers, who until now had only two-dimensional images obtained by ultrasound, and in the explanation of a diagnosis to a patient. The parts 1 0, 20, 30 may further comprise retaining means adapted to hold together the three parts 10, 20, 30 assembled.

 These retaining means may be imants, form-complementary means, a strap surrounding the parts, etc.

 Preferably, the arrangement of the retentive means is chosen so as not to modify the appearance of the exploited faces of the pieces (that is to say the upper faces 1 1 and lower 21).

 For example, when the retaining means comprise complementary shape means, such as protuberances and complementary cavities, the protuberances are preferably made on the lower faces 25 and 31 of the central and upper parts 20 respectively, while the associated cavities correspond to cavities existing in the upper faces 1 1 and 21 of the parts 10 and 20, and are constituted for example by the arteries, veins, valves, etc. upper faces 1 1 and 21 of the central parts 20 and lower 10.

 Thus, as illustrated in Figures 2 and 3B appended, the lower face 25 of the central piece 20 may comprise a protuberance 41 of rounded shape, corresponding to the shape and position of the descending aorta made in the upper face 1 1 of the lower part 10, as well as protuberances 42 adapted to abut with the lower part of the left ventricles 1 5 and / or right 13, and / or the left atrium 14 (not shown in the figures) of the face superior 1 1.

Likewise, as illustrated in FIGS. 3A and 4B appended, the lower face 31 of the upper piece 30 may comprise two protuberances 43 of rounded shape, corresponding to the shape and position of the descending aorta 16 and the aortic valve. 23 made in the upper face 21 of the central piece 20, and a protrusion 44 adapted to abut with a lower portion of the right ventricle 13. According to a preferred embodiment, the device 1 is made of a resin (for example polyurethane). For this, each piece 10, 20, 30 of the device 1 may for example be obtained by casting in a mold. However, given the complexity of the shape of each of the pieces, then preferably used is a mold made of a material that can be deformed to facilitate their extraction, for example a silicone mold.

Of course, the present invention is not limited to the embodiments described above and shown in the drawings, but the skilled person will be able to make many variations and modifications.

Claims

1. Device (1) reproducing a fetal heart in three dimensions, characterized in that it is adapted to visualize at least two sectional planes, the first plane (Pi) corresponding to the fetal cut "of the four cavities" and the second plane ( P ₂ ) corresponding to the fetal cut "large vessels", and comprising at least two pieces (10, 20),  a first part (10) corresponding to a lower portion of the fetal heart, having a substantially plane upper face (1 1) corresponding to the first section plane (Pi), and a second piece (20), having the shape of a dihedron whose apex angle is acute, and having a substantially flat upper surface (21) corresponding to the second section plane (P ₂ ), the edge (24); ) of the dihedron forming said second piece (20) being aligned with the line (D) from the section of the two section planes (Pi and P ₂ ). 2. Device (1) according to revendication 1, further comprising a third part (30) corresponding to an upper part of the fetal heart, having a bottom surface (31) in the form of dihedron whose apex angle is obtuse and adapted to be disposed on the first (10) and the second piece (20). 3. Device (1) according to one of claims 1 and 2, wherein the upper face (1 1) of the first part (10) and the lower face (25) of the second part (20) are complementary shapes and are able to fit together. 4. Device (1) according to claim 3, further comprising retaining means (41 - 44) adapted to hold the parts (10, 20, 30) in position relative to each other. 5. Device (1) according to claim 4, wherein the retaining means (41-44) are form-complementary means or magnets. 6. Device according to claim 5, wherein the retaining means (41 - 44) are protuberances extending from one of the lower and upper faces (25, 31; 1 1, 21) of the parts (20, 30) and adapted to engage cavities (16, 17). , 22, 23) made in the other of corresponding lower and upper faces (25, 31, 11, 21). 7. Device (1) according to claim 6, wherein the cavities (1 6, 1 7, 22, 23) correspond to existing cavities in the upper faces (1 1, 21) of the parts (10, 20). 8. Device (1) according to one of claims 1 to 7, characterized in that it is made of resin. 9. Device (1) according to one of claims 1 to 8, characterized in that the upper surface (1 1) of the lower part (10) is covered by two-thirds by the central piece (20). 10. A method of manufacturing a device (1) l l uned leses claims 1 to 9, characterized in that at least one of the parts (10, 20 30) is made by injection-molding in a mold silicone.