JP5134741B2 - Ultrasonic inspection unit or ultrasonic inspection device - Google Patents

Description

  The present invention relates to a water immersion ultrasonic inspection unit or an ultrasonic inspection apparatus particularly used for breast cancer screening and the like.

  At present, a direct contact method in which an engineer uses an ultrasonic probe and collects image data while directly applying the ultrasonic probe to the body surface is used for ultrasonic inspection. In order to use ultrasonic examination for screening, an engineer that can collect reproducible data in a short time is required instead of being manually performed by an engineer. The direct contact method is currently used for breast examination, but since the breast is soft tissue and the breast deforms when it comes in contact with the probe, the automated method simply moves the probe mechanically. Not reproducible and not suitable for screening devices. On the other hand, breast deformation is avoided if the probe is slightly separated from the body surface, but since ultrasonic waves can hardly propagate in the air, a water immersion method in which warm water or the like is interposed between the probe and the body surface has been proposed ( For example, see Patent Document 1).

As the water immersion method proposed so far, the most suitable method is to install the linear array probe in a liquid container filled with hot water and mechanically rotate the linear array probe around the nipple portion. it is conceivable that. That is, cross-sectional image data is collected in real time by the linear array probe, and the cross-sectional image of the whole breast is collected by moving the cross-section by rotation and rotating the probe once. In addition, because of the physical properties of the ultrasonic wave, the distance between the probe and the body surface is preferably as small as possible, and it is desirable that the ultrasonic beam is incident on the body surface at a right angle (the probe and the body surface are parallel). For this purpose, a method has been proposed in which the probe is inclined so that the probe surface and the body surface are as close to parallel as possible.
Japanese Patent Publication No.62-4989

  In the proposal of the conventional water immersion method, the liquid container has the shape of a normal container for containing liquid, and the side in contact with the body surface is flat. The tilt angle of the probe can be adjusted, but is kept constant while the probe is rotating. However, since the breast is located on the rib cage and the rib cage is not flat, it is difficult for the liquid container to come into contact with the convex portion of the rib cage to bring the warm water portion into close contact with the entire breast. In addition, when the probe is tilted to be as parallel and close to the body surface as possible, the tilt angle and distance are limited by the convex portion of the rib cage.

  The present invention is intended to solve such a conventional problem, and provides an ultrasonic inspection apparatus in which the entire breast can be brought into close contact with the warm water portion and the probe can be as close to and parallel to the body surface as possible. For the purpose.

  A first means for solving the above problems includes an ultrasonic probe in which transducers are arranged in an array, a rotating mechanism that rotates the ultrasonic probe, a liquid container that stores the ultrasonic probe and liquid, In the ultrasonic inspection unit consisting of the above, the body surface side edge of the liquid container is not in a flat shape.

  The second problem-solving means is to make the portion of the liquid container having a concave edge on the body surface side correspond to the rib cage in the body axis direction of the subject and make the convex portion correspond to the rib cage in the cross-sectional direction.

  The third problem-solving means is that the convex part of the edge on the body surface side of the liquid container protrudes from the upper part of the table on which the subject is placed.

  In a fourth problem solving means, the liquid container is composed of a non-stretchable frame and a stretchable ultrasonic transmission film.

  The fifth problem solving means is that the liquid container has a sealed or semi-sealed structure so that the pressure in the container is equal to or higher than atmospheric pressure.

  A sixth problem solving means includes an ultrasonic probe in which transducers are arranged in an array, a rotation mechanism that rotates the ultrasonic probe, a control mechanism that controls the tilt angle and / or vertical position of the probe, In an ultrasonic inspection unit including an ultrasonic probe and a liquid container for storing a liquid, it is possible to control the inclination angle and / or the vertical position of the ultrasonic probe while rotating the ultrasonic probe.

  The seventh problem solving means controls the tilt angle and / or the vertical position of the ultrasonic probe using the ultrasonic wave reflected wave information from the body surface.

  The eighth problem solving means has a function of controlling an inclination angle and / or an up / down position necessary for data collection thereafter based on data of a cross-sectional image obtained at a predetermined inclination angle and an up / down position. Is.

  The ninth problem solving means is to provide a function capable of connecting the above-described ultrasonic inspection unit to a normal ultrasonic inspection apparatus.

Effects and effects of the invention

  The operation and effect of the first problem solving means are as follows. That is, the liquid container can be brought as close as possible to the curved rib cage by making the body surface side edge of the liquid container not on a plane, and as a result, the hot water portion can be brought close to the entire breast.

  The action and effect of the second problem solving means is that the shape of the rib cage is close to a straight line in the body axis direction and curved in the cross-sectional direction, and the portion on the body surface side of the liquid container having a concave edge is examined. By matching the ribcage in the body axis direction of the person and the convex part corresponding to the cross-sectional direction, it is possible to obtain an optimum shape for bringing the hot water part close to the entire breast.

  The operation and effect of the third problem solving means is that the inspection unit including the gantry is configured so that the convex part of the edge on the body surface side of the liquid container protrudes from the upper part of the table on which the subject is placed. When testing in the prone position, the entire breast is in close contact with the liquid container and data for the entire breast can be collected.

  The operation and effect of the fourth problem solving means is that the liquid container is composed of a non-stretchable frame and a stretchable ultrasonic transmission film, so that the body surface side edge of the non-stretchable frame extends along the rib cage. Because of its shape, it does not partially contact the rib cage, and the portion that contacts the breast can be stretched and adhered to the breast shape by the stretchable film, so that warm water can be used without causing discomfort to the subject. The part can be close to the whole breast.

  The action and effect of the fifth problem-solving means is that the liquid container has a sealed or semi-sealed structure so that the pressure in the container is equal to or higher than atmospheric pressure. In addition, the surroundings are raised by the volume of the depressed portion in the center, and the adhesion to the whole breast is further improved.

  The action and effect of the sixth problem solving means is that the tilt angle or the vertical position is adjusted so that the tilt angle is small at the concave portion of the liquid container and the tilt angle is large at the convex portion while rotating the ultrasonic probe. Alternatively, by controlling both of them, the distance between the probe and the breast surface is always reduced, and a high-quality image can be obtained.

  The action and effect of the seventh problem solving means is that the optimum inclination angle and / or vertical position of the ultrasonic probe can be automatically controlled by using the ultrasonic wave reflected wave information from the body surface.

  The action and effect of the eighth problem solving means is to control the tilt angle and / or vertical position required for subsequent data collection based on the cross-sectional image data obtained at the predetermined tilt angle and vertical position. By doing so, the optimum inclination angle and position can be automatically set even for the shape of the breast having individual differences.

  The action and effect of the ninth problem solving means is that the normal ultrasonic inspection apparatus can be used as a single apparatus by providing a normal ultrasonic inspection apparatus with a function capable of connecting an ultrasonic inspection unit. Furthermore, if an ultrasound examination unit is added, it can be used as a breast cancer screening device, so the range of use is expanded.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  FIG. 1 is a system configuration diagram showing the entire ultrasonic inspection apparatus of the present invention. The ultrasonic inspection unit 1 includes a liquid container, an ultrasonic linear array probe (hereinafter simply referred to as a probe), a probe rotation mechanism, a support mechanism, and the like, and is a unit that transmits and receives ultrasonic pulses to and from a subject. This will be described in detail later.

  A portion B surrounded by an alternate long and short dash line in FIG. 1 is an ultrasonic transmission / reception circuit and image generation means for generating a cross-sectional image from the received signal. A pulse voltage is generated in the transmission circuit and transmitted to the probe in the ultrasonic inspection unit 1 to generate an ultrasonic pulse. The ultrasonic pulse enters the living body, and the reflected wave is detected by the same probe and supplied to the receiving circuit 2. The reception signal processing circuit 3 processes the signals of the plurality of vibration elements received by the reception circuit and writes them into a digital scan converter (hereinafter referred to as DSC) 4. The DSC forms a two-dimensional cross-sectional image using the obtained received signal, and the cross-sectional image is displayed on the monitor 12 via the image composition unit 5.

  The mechanism control circuit 8 controls the control mechanism of the rotation and tilt angle of the probe in the ultrasonic inspection unit 1. The position / angle detection unit 7 detects the rotation angle and the tilt angle by a sensor in the control mechanism. The rotation angle and the tilt angle are superimposed on the image by the image composition unit 5 via the additional information unit 9 and displayed on the monitor 12. The tomographic image and additional information are recorded in the memory and can be read out when necessary. These are all computer-controlled by a CPU (central control unit) 11. In FIG. 1, the signal flow is indicated by a solid line, and the control signal from the computer is indicated by a dotted line.

  A portion C surrounded by a one-dot chain line in FIG. 1 is a monitor 12 for displaying the generated cross-sectional image and an input means 13 for setting photographing conditions and display conditions.

  FIG. 2 shows an example of a cross-sectional view of an ultrasonic inspection unit 1 that is generally considered conventionally. The liquid container is composed of a non-stretchable frame 21, and a probe 24 is provided in the liquid container, and hot water 25 is filled up to the water surface 22. A large number of vibration elements 23 are provided above the probe 24 to transmit and receive ultrasonic waves. At the time of examination, a breast is inserted into the warm water 25 from above, an ultrasonic pulse is transmitted from the vibration element 23 to the breast tissue via the warm water 25, and a reflected wave from the breast tissue is received again by the vibration element 23 via the warm water 25. Is done. Linear electronic scanning is performed by the large number of vibration elements 23, and a cross-sectional image is obtained in real time. On the other hand, the probe 24 is attached to a rotating shaft 27, and the rotating shaft 27 is rotated by a motor 29 to perform mechanical scanning, and a cross-sectional image in a 360-degree direction can be collected. The rotating shaft is supported and sealed by bearings 28a and 28b. Further, there is a shaft 26 at a portion where the probe 24 is coupled to the rotary shaft 27, and the tilt angle of the probe 24 can be changed by a driving mechanism not shown in the drawing. Warm water of about 37 ° C. is supplied from the water supply pipe 30 into the liquid container and drained from the drain groove 31 through the drain pipe 32. A water supply valve 33 and a water discharge valve 34 are provided to control water supply and drainage. The frame 21 of the liquid container is fixed to the gantry 35.

  FIG. 3A is a diagram illustrating a non-stretchable frame 21 of a liquid container that is generally considered in the past. The general shape of the edge 40 on the body surface side of the non-stretchable frame 21 is a flat circle, and this circle is considered to be on a plane. The liquid container is filled with warm water, and a breast is inserted from above to conduct an examination. On the other hand, the edge on the body surface side of the non-stretchable frame 21 in the present invention is not a flat circle but an uneven shape as shown in FIG. That is, it has a curved shape having a concave portion 41 and a convex portion 42. Further, as shown in FIG. 4, FIG. 6, or FIG. 7, the upper part of the concavo-convex shape is covered and sealed with a thin stretchable ultrasonic transmission film 37 of about 0.1 to 0.3 mm, and the concave part So that the water does not overflow. In this way, by making the edge on the body surface side of the non-stretchable frame 21 into a curved shape with irregularities, the entire breast can be sufficiently inserted into the warm water through the ultrasonic transmission film 37, and the breast It becomes possible to collect the entire image data.

  FIG. 4 is a conceptual diagram showing a state in which the liquid container is attached to the gantry. The probe and the probe driving mechanism shown in FIG. 2 are omitted for simplicity. In this figure, the subject presses the breast against the liquid container from above, that is, the prone position test method. 4A, the direction represented by SS corresponds to the cross-sectional direction of the body, and in FIG. 4B, the direction represented by LL corresponds to the body axis direction. As can be seen from this figure, the concave portion 41 at the edge of the frame is substantially the same height as the top surface 36 of the gantry, but the convex portion 42 is higher than the top surface 36 of the gantry. In the example of FIG. 4, the gantry is box-shaped, but a berth that is long in the LL direction may be used instead of the gantry.

  The reason why the entire breast can be sufficiently inserted into the hot water 25 by using such a shape will be described in detail below. FIG. 5 (a) shows a cross-sectional view when the subject presses the breast against a conventional liquid container. FIG. 5 is drawn smaller than FIG. 3 due to space limitations. The breast 43 is located on the rib cage, and the rib cage surrounded by the ribs has a substantially linear shape in the body axis direction, but the cross-sectional shape has a shape surrounded by a curve. That is, a curved surface is formed from the rib cage central portion 45 having the sternum through the breast central portion 44 to the body side portion 46, and the breast is positioned thereon. Therefore, when trying to insert the entire breast into warm water as much as possible, it is preferable to take a posture in which the body side part 46 is slightly lowered by slightly rotating the body around the body axis as shown in FIG. In the conventional example of FIG. 5A, the edge 40 on the body surface side of the non-stretchable frame 21 is flat, so that when the breast 43 is inserted, the rib cage 44 at the center of the breast comes into contact with the edge 40. No further breast 43 can be inserted. In such a state, a large gap is formed between the peripheral portion of the breast and the liquid container, and data of the entire breast cannot be collected.

  FIG. 5 (b) shows a cross-sectional view when the subject inserts the breast 43 into the liquid container of the present invention. In this case, the concave portion 41 of the non-stretchable frame 21 corresponds to the rib cage 44 in the central portion, and the convex portion 42 corresponds to the rib cages 45 and 46 in the peripheral portion. Therefore, the rib cage 44 in the central portion does not hit the edge. It can be further inserted into the liquid container, and the gap between the body surface of the peripheral portion and the hot water can be minimized.

  6 (a) and 6 (b) are diagrams in the case where a stretchable ultrasonic transmission film 37 is attached to the top of the non-stretchable frame 21 and sealed with hot water, and the non-stretchability of the liquid container is shown. 5 (a) and FIG. 5 (b) are partially shown so that the relationship between the frame 21 and its edges 40, 41 and 42, the ultrasonic transmission film 37, the breast 43, and the rib cages 44, 45 and 46 can be easily understood. It is a slightly enlarged view. When the breast 43 is pressed against the ultrasonic transmission film 37, the central portion of the ultrasonic transmission film 22 is recessed, and the surrounding film is lifted by the amount of water. The upper part of the edge 40 of the frame 21 shown in FIG. 6A can be covered with a stretchable ultrasonic transmission film 37 even in the conventional example in which the edge 40 of the frame 21 is planar. Since it touches the edge 40 and cannot lower the breast 43 any more, it is difficult to press the entire breast against the ultrasonic transmission film 37. On the other hand, in the embodiment of the present invention shown in FIG. 6B, the edge 41 of the non-stretchable frame 21 is recessed, so that the breast 43 can be inserted deep enough, and the circumference of the breast 43 is sufficient. Thus, the ultrasonic transmission film 37 is lifted, and the entire breast can be brought into close contact with the ultrasonic transmission film 37.

  The entire breast is inserted deeply into the liquid container by providing the concave portion 41 and the convex portion 42 at the edge of the frame 21 of the liquid container, but the cross section is parallel to the body axis and the transverse direction perpendicular to the body axis. It differs in the longitudinal section (sagittal) direction. FIG. 7A shows the positional relationship between the cross section of the ribs 44, 45, 46 and the breast 43 and the probe 24, and FIG. 7B shows the vertical cross section of the ribs 47, 48, 44 and the breast 43 and the probe 24. Indicates the positional relationship. As shown in FIG. 7A, in the cross section, the thoracic region 45 near the sternum, the thoracic region 44 corresponding to the central part of the breast, and the thoracic region 46 on the side of the body are curved, and the ultrasonic probe 24 and the body surface are brought closer to each other. In order to make the sound beam incident on the body surface at a right angle as much as possible, the tilt angle of the probe should be increased to some extent. On the other hand, as shown in FIG. 7B, in the longitudinal section, the chest rib 47 in the head direction, the rib cage 44 corresponding to the central part of the breast, and the rib cage 48 in the abdomen direction are substantially straight, and the ultrasound probe 24 is in the rib cage 47, 48. In order to make the ultrasonic beam incident at a right angle to the body surface as much as possible, the inclination angle of the probe 24 should be reduced to some extent. That is, it is desirable to change the tilt angle according to the rotation angle of the probe 24.

  Next, two examples of a method of changing the tilt angle according to the rotation angle will be described. FIG. 8A shows a perspective view of a concave disk 50 obtained by bending the disk. In the figure, the bending is emphasized, but in reality it is a little more flat. A sectional view 50a of the concave disk 50 in the SS direction is shown in FIG. 8B, and a sectional view 50b in the LL direction is shown in FIG. 8C. In the SS direction, the curve is slightly upward as it goes to the periphery, and in the LL direction, it is almost a straight line at a low position. 9 (a) and 9 (b) are cross-sectional views when the curved disk 50 is fixed under the probe, FIG. 9 (a) is a cross-sectional direction of the body, and FIG. 9 (b) is a vertical cross-section. It is sectional drawing of a direction. A knob 51 is provided at a slightly lower center of the probe 24, and a lower end portion of the knob 51 has a structure with very little friction with a curved disk 50 such as a bearing. When the probe 24 rotates, the knob 51 moves on the curved surface disk 50. As the probe 24 rotates, the inclination angle increases in the transverse section direction SS, and the inclination angle decreases in the longitudinal section direction LL. The tilt angle changes continuously. Further, the position of the entire probe can be moved up and down as necessary.

  FIG. 10 shows another embodiment in which the tilt angle and the vertical position are changed as the probe 24 rotates. FIG. 10A is a diagram showing the positional relationship between the cross section of the breast 43, the breast surface position 53, and the probe 24. The probe surface direction is the X axis, and the direction orthogonal to the X axis is the Y axis. The distance from the rotation center of the probe to the i-th scanning line is xi, and the distance from the probe surface to the body surface on the scanning line is yi. The first strong ultrasonic reflection on the scanning line is the reflection from the body surface, and the value of yi can be easily measured automatically as the distance to this reflected wave. If the scanning line interval is Δx, the value of xi is obtained as xi = Δx × i. The probe 24 can be moved up and down by a probe control mechanism (not shown) or the inclination angle can be changed.

  FIG. 10B shows the right half from the center of FIG. A straight line approximated to the curve 53 on the breast surface is a straight line X′-X ′, the angle of the straight line X′-X ′ with respect to the X axis is θ, and the intercept with the Y axis is yo. Further, the maximum value of the distance between the curve 53 below the straight line X′-X ′ and the straight line X′-X ′ is δ. The value of θ is used as the optimum tilt angle of the probe for allowing the ultrasonic beam to enter the curve 53 on the breast surface vertically. If the probe tilt angle is θ and the probe is lifted up by (yo−δ), the probe surface just touches the breast surface, that is, the curve 53. Therefore, for safety, avoid the contact and set the minimum distance between the probe surface and the breast surface to Δ Lift the probe up by (yo−δ−Δ). For example, a value of 3 mm or the like is used as the value of Δ. FIG. 10C shows a state in which the probe 24 is tilted by θ from the initial state of FIG. 10B and lifted up by (yo−δ−Δ). When the cross-sectional image obtained in this way is displayed on the monitor 12 of FIG. 1, the probe surface is displayed horizontally, so that it becomes as shown in FIG. Here, the new coordinates are X ′ and Y ′. When actually displaying on the monitor 12, the probe side is customarily displayed on the upper side, and the image is an upside down view of FIG.

  When this method is applied to automatically control the tilt angle and distance while the probe 24 rotates, θ and (yo−δ−Δ) are obtained from the curve 53 obtained from the data of one frame, and the same. Instead of controlling the optimum tilt angle and the optimum distance of the frame, the optimum tilt angle and the optimum distance of the next frame or several frames after are controlled. Since the cross-sectional image does not change suddenly due to the rotation of the probe 24, the optimum inclination angle and the optimum distance can always be automatically controlled with respect to the rotation of the probe 24 in this way.

  In FIGS. 10A to 10D, the method of optimally controlling the probe tilt angle and distance at the same time has been described. To simplify the control, the probe is rotated once before starting the inspection. Alternatively, pre-scanning may be performed to obtain the shortest distance at which the probe does not contact the breast surface in a cross-sectional image in a 360-degree direction, and only the probe tilt angle may be changed while the distance is fixed.

  In the embodiment of the present invention, the ultrasonic permeable membrane is provided on the upper part of the liquid container, and the method in which the subject presses the breast from above has been described. However, a method is also possible in which the subject is in a supine position on the bed and the liquid container is lowered from above. In this case, the liquid container, the probe, and the drive mechanism are all turned upside down, and the liquid container is not fixed to the gantry and is supported by an arm that can move up and down.

  Although the contents of the present invention have been described in detail with respect to the ultrasonic examination unit 1 indicated by A in FIG. 1, the whole of A, B, and C in FIG. When the manufacturer actually sells to the user, of course, the entire system of FIG. 1 may be sold as an ultrasonic inspection apparatus, but for users who already have a general-purpose ultrasonic diagnostic apparatus, an ultrasonic inspection unit is available. A function for operating only the ultrasonic inspection unit 1 may be added to a general-purpose ultrasonic diagnostic apparatus by purchasing only one. Alternatively, if a function for operating the ultrasonic inspection unit 1 is incorporated in a general-purpose ultrasonic diagnostic apparatus in advance, and the ultrasonic inspection unit 1 is an option, only a general-purpose ultrasonic diagnostic apparatus is purchased, and if necessary It is possible to easily carry out breast cancer screening by purchasing an additional ultrasonic examination unit 1.

Overall system configuration of the apparatus of the present invention Configuration diagram of conventional ultrasonic inspection unit (A) Shape of conventional liquid container (B) Shape of the liquid container of the present invention The figure explaining that a liquid container protrudes from the stand on the surface of a mount (A) The figure which shows that a rib cage contacts an edge in a prior art example (B) The figure which shows that it is hard to be restrict | limited to a rib cage in this invention. (A) Explanatory drawing when a stretchable ultrasonic transmission membrane is used in a conventional example (B) Explanatory drawing when a stretchable ultrasonic transmission membrane is used in the present invention (A) The figure which shows the probe inclination angle in a cross-sectional direction (B) The figure which shows the probe inclination angle in a longitudinal cross-section direction Explanatory drawing of curved disk for controlling probe tilt angle (A) Cross-sectional view in the cross-sectional direction when a curved disk is attached (B) Sectional view in the longitudinal section direction when a curved disk is attached The figure explaining the method of automatically controlling the tilt angle and vertical position of the probe

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic inspection unit 21 which is the object of the present invention Non-stretchable frame 24 of liquid container Ultrasonic probe 27 Probe rotating shaft 36 Top surface of mount 37 Elastic ultrasonic transmission film 40 Body surface side of non-stretchable frame Edge (conventional example)
41 Concave portion of edge of body surface side of non-stretchable frame (present invention)
42 Convex part of body edge of non-stretchable frame (present invention)
44 Thorax 50 located at the center of the breast 50 Curved disk 51 for controlling the tilt angle of the probe Knob 53 in contact with the curved disk Curve indicating the body surface of the breast cross section

Claims (1)

An ultrasonic probe transducer are arranged in an array, said a rotating mechanism for rotating the ultrasonic probe, comprising: a liquid container for housing the ultrasonic probe and a liquid, the liquid container body front side edge of the shaped ultrasound unit or ultrasonic inspection apparatus characterized by having a concave shape in a substantially perpendicular cross direction convex to the body axis in the body axis direction of the examinee.

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