Guide wire, torquer for elongated medical device, method for manufacturing guide wire, device for manufacturing guide wire, and blood vessel cross-sectional image display system

Abstract

This guide wire includes a body and an ultrasonic sensor. The body is elongated and has a distal end portion that bends at a bending point, which is the proximal end of the distal end portion. The ultrasonic sensor is securely mounted on the body so that an ultrasonic transmission / reception surface faces the outer circumference in a cross section of the body. The ultrasonic sensor is positioned in the vicinity of the bending point in the body and at a bending base portion that is closer to the proximal end side than the bending point. In a cross section of the body, the ultrasonic sensor is positioned so that the bending direction of the distal end portion is present in a position range where the sound pressure of an ultrasonic wave transmitted from the ultrasonic sensor is equal to or higher than the half value of the maximum value.

Description

Guidewire, torquer for long medical device, method for manufacturing guidewire, guidewire manufacturing device, and blood vessel cross-sectional image display system

[0001] The technology disclosed in this specification relates to a guidewire, a torquer for an elongated medical device, a method for manufacturing a guidewire, a guidewire manufacturing apparatus, and a blood vessel cross-sectional image display system.

[0002] Guidewires are used to treat lesions such as stenoses and occlusions in blood vessels. In procedures for treating lesions using guidewires, if the guidewire passes through a false lumen, which is outside the true lumen, which is the region inside the vascular intima, there is a risk of, for example, dissection of the vascular wall. Therefore, in these procedures, it is important to reliably pass the guidewire through the true lumen. To reliably pass the guidewire through the true lumen, the operator needs to be able to accurately grasp the position and orientation of the guidewire within the blood vessel.

[0003] A known information processing system includes an IVUS (Intervascular Ultrasound) device, an X-ray imaging device, and a diagnosis support device (see, for example, Patent Document 1). This system displays an image of a blood vessel and an image of a guidewire using a pullback image obtained by the IVUS device and a contrast image obtained by the X-ray imaging device.

[0004] Japanese Patent Application Laid-Open No. 2022-32595

[0005] The above-mentioned known systems have a problem in that the device configuration for determining the position and orientation of the guidewire within the blood vessel is large-scale.

[0006] This specification discloses a technique that can solve the above-mentioned problems.

[0007] The guidewire disclosed herein includes a main body and an ultrasonic sensor. The main body is elongated, and a distal end portion is bent at a bending point at the proximal end of the distal end portion. The ultrasonic sensor is fixedly mounted on the main body such that an ultrasonic transmission / reception surface faces the outer periphery in a cross section of the main body. The ultrasonic sensor is located near the bending point in the main body and at a bending root portion that is proximal to the bending point. The ultrasonic sensor is arranged so that the bending direction of the distal end portion is within a positional range in which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor is equal to or greater than half of the maximum value in the cross section of the main body.

[0008] Schematic diagram of a blood vessel cross-sectional image display system according to a first embodiment. Schematic diagram of a guidewire. Schematic diagram of a guidewire. Schematic diagram of a guidewire. Schematic diagram of a graph torca. Schematic diagram of a torca. Schematic diagram of an information processing system using an ultrasonic echo device. Schematic diagram of an image displayed on a display device. Schematic diagram of an example of a procedure using a blood vessel cross-sectional image display system. Schematic diagram of a method for manufacturing a guidewire. 18 is a diagram showing the state of the guide wire when the transmission direction and bending direction are coincident; 19 is a diagram showing the state of the guide wire when the transmission direction and bending direction are coincident; 20 is a diagram showing the state of the guide wire when the transmission direction and bending direction are not coincident; 21 is a diagram showing the state of the guide wire when the transmission direction and bending direction are not coincident; 22 is a diagram showing the state of the guide wire when the transmission direction and bending direction are not coincident; 23 is a diagram showing the structure of a Torca different in form from the Torca shown in FIGS. 7 and 8; 24 is a diagram showing the structure of a blood vessel cross-sectional image display system in a second embodiment;

[0009] (First embodiment) (Configuration of blood vessel cross-sectional image display system) Fig. 1 is an explanatory diagram showing a schematic configuration of a blood vessel cross-sectional image display system 10 in the first embodiment. The blood vessel cross-sectional image display system 10 is a system used when a technician treats a lesion in a blood vessel using a guidewire while referring to a blood vessel cross-sectional image. The blood vessel cross-sectional image display system 10 has a guidewire 100, a torquer 200, a connector 310, an ultrasonic echo device 320, and a display device 330. The guidewire 100 is an elongated medical device that is inserted into a blood vessel.

[0010] (Configuration of Guidewire 100) FIG. 2 is an explanatory diagram schematically illustrating the configuration of the guidewire 100 according to this embodiment, showing a YZ longitudinal cross section of the guidewire 100. The positive Z-axis direction is the distal end (distal side) that is inserted into the body, and the negative Z-axis direction is the proximal end (proximal side) that is manipulated by the operator. In this specification, the distal end of the guidewire 100 and each of its components is referred to as the "distal end," the distal end and its vicinity are referred to as the "distal portion," the proximal end is referred to as the "proximal end," and the proximal end and its vicinity are referred to as the "proximal portion." The transverse cross section of the guidewire 100 and each of its components refers to a cross section perpendicular to the longitudinal direction. The longitudinal cross section of the guidewire 100 and each of its components refers to a cross section parallel to the longitudinal central axis. The direction perpendicular to the longitudinal direction of the guidewire 100 and each of its components is referred to as the radial direction. The outer diameter of the guidewire 100 and each of its components refers to the width along the radial direction.

[0011] The guidewire 100 has an elongated main body 102 extending along a central axis Ax, and an ultrasonic sensor 140 mounted on the main body 102. The guidewire 100 is an imaging guidewire that uses the ultrasonic sensor 140 to visualize (image) the condition of a blood vessel.

[0012] The distal end portion 105 of the main body 102 is bent at a predetermined bending angle θ1 at a bending point 104, which is the base end of the distal end portion 105. Hereinafter, the portion of the main body 102 excluding the distal end portion 105 is referred to as the base portion 106. In the state shown in FIG. 2 , the longitudinal direction of the base portion 106 is the Z-axis direction, and the bending direction D2 of the distal end portion 105 relative to the base portion 106 is the positive direction of the Y-axis. The bending angle θ1 is, for example, 3 degrees or more and 45 degrees or less. The bending angle θ1 may be 5 degrees or more and 40 degrees or less, or 10 degrees or more and 35 degrees or less. The distance from the distal end of the guidewire 100 to the bending point 104 along the longitudinal direction of the guidewire 100 is, for example, 0.5 mm or more and 10.0 mm or less. The distance may be 1.0 mm or more and 8.0 mm or less, or 1.5 mm or more and 6.0 mm or less.

[0013] The body 102 of the guidewire 100 includes a core wire 110 , a distal coil 120 , and a proximal coil 130 .

[0014] The core wire 110 is a long member. The core wire 110 has a large diameter portion 115, a first tapered portion 114, an intermediate diameter portion 113, a second tapered portion 112, and a small diameter portion 111. The large diameter portion 115 is a rod-shaped portion having a substantially constant outer diameter. The outer diameter of the large diameter portion 115 is, for example, approximately 0.2 mm to 3.0 mm. The intermediate diameter portion 113 is a rod-shaped portion located closer to the distal end than the large diameter portion 115 and having a substantially constant outer diameter that is smaller than the outer diameter of the large diameter portion 115. The small diameter portion 111 is a rod-shaped portion located closer to the distal end than the intermediate diameter portion 113 and having a substantially constant outer diameter that is smaller than the outer diameter of the intermediate diameter portion 113. The first tapered portion 114 is located between the large-diameter portion 115 and the intermediate-diameter portion 113, and is a tapered portion whose outer diameter gradually decreases from the boundary with the large-diameter portion 115 toward the boundary with the intermediate-diameter portion 113. The second tapered portion 112 is located between the intermediate-diameter portion 113 and the small-diameter portion 111, and is a tapered portion whose outer diameter gradually decreases from the boundary with the intermediate-diameter portion 113 toward the boundary with the small-diameter portion 111. In this embodiment, the proximal end of the small-diameter portion 111 is located proximally closer to the bending point 104. That is, the small-diameter portion 111 is bent at the bending point 104. The cross-sectional shape at each position of the core wire 110 may be any shape. The cross-sectional shape at each position of the core wire 110 may be, for example, a circle, a partial circle (e.g., a semicircle, a broken circle, or a bow), an ellipse, a rectangle, a parallelogram, a trapezoid, a rhombus, or the like. The cross section of the core wire 110 at each position is not limited to the above-described shape in strict terms, and may be approximately the above-described shape. The cross section of the core wire 110 may have a different shape at each position along the longitudinal direction.

[0015] The core wire 110 is made of, for example, a conductive material. Examples of materials that can be used to form the core wire 110 include stainless steel (SUS302, SUS304, SUS316, etc.), Ni-Ti alloys, piano wire, etc. The entire core wire 110 may be made of the same material, or different portions may be made of different materials.

[0016] The distal coil 120 and the proximal coil 130 (hereinafter collectively referred to as "coils 120, 130") are hollow cylindrical members formed by helically winding a single wire. The coils 120, 130 are arranged to cover a portion of the core wire 110 from the outer periphery. In this embodiment, the distal coil 120 covers a portion of the thin-diameter portion 111 of the core wire 110. In this embodiment, the proximal end of the distal coil 120 is located proximally relative to the bending point 104. That is, the distal coil 120 is bent at the bending point 104. The proximal coil 130 is located proximally relative to the distal coil 120. The distal end of the proximal coil 130 is located a predetermined distance proximally from the proximal end of the distal coil 120. In this embodiment, the proximal coil 130 covers a part of the small diameter section 111 of the core wire 110 , the second tapered section 112 , and a part of the intermediate diameter section 113 .

[0017] Examples of materials that can be used to form the coils 120, 130 include stainless steel (SUS302, SUS304, SUS316, etc.), Ni-Ti alloys, piano wire, platinum, gold, tungsten, and alloys thereof. The coils 120, 130 may be entirely made of the same material, or portions may be made of different materials. The coils 120, 130 may be made of the same material, or portions may be made of different materials.

[0018] The coils 120 and 130 are joined to the core wire 110. More specifically, the distal end of the distal coil 120 is joined to the core wire 110 via a first joint 161, and the proximal end of the distal coil 120 is joined to the core wire 110 via a second joint 162. The first joint 161 functions as the distal tip of the guidewire 100. The distal end of the proximal coil 130 is joined to the core wire 110 via a third joint 163, and the proximal end of the proximal coil 130 is joined to the core wire 110 via a fourth joint 164. The coils 120 and 130 may be joined to the core wire 110 via joints formed at other positions. Some of the above joints may be omitted. Examples of materials used to form each of the above-mentioned joints include metal solder (Au-Sn alloy, Sn-Ag alloy, Sn-Pb alloy, Pb-Ag alloy, etc.), brazing material (aluminum alloy brazing, silver brazing, gold brazing, etc.), adhesive (epoxy adhesive, etc.), etc.

[0019] The ultrasonic sensor 140 is an ultrasonic probe that transmits ultrasonic waves based on a transmission electrical signal, receives ultrasonic waves (echoes) that are reflected back from inside and outside a blood vessel, and outputs a received electrical signal. In this embodiment, the ultrasonic sensor 140 is composed of a single ultrasonic sensor element. However, the ultrasonic sensor 140 may be composed of multiple ultrasonic sensor elements arranged in a line, or multiple ultrasonic sensor elements arranged two-dimensionally.

[0020] The ultrasonic sensor 140 is fixedly mounted on the main body 102 of the guidewire 100 such that an ultrasonic transmission / reception surface of the ultrasonic sensor 140 faces the outer periphery in a transverse cross section of the main body 102. The ultrasonic sensor 140 is capable of transmitting ultrasonic waves radially outward from the main body 102. The ultrasonic sensor 140 is located in a bend root region 107 near a bend point 104 in the main body 102 and on the proximal side of the bend point 104. The bend root region 107 is located, for example, in a range from the bend point 104 to a position 20 mm away from the proximal side along the longitudinal direction of the main body 102. In this embodiment, the bend root region 107 is a region sandwiched between the distal coil 120 and the proximal coil 130 along the longitudinal direction of the main body 102.

[0021] Fig. 3 is an explanatory diagram showing the configuration of the vicinity of the ultrasonic sensor 140 in the guide wire 100. Fig. 3 shows an enlarged view of the configuration of part X1 in Fig. 2. The ultrasonic sensor 140 has a piezoelectric element 143, which is an ultrasonic oscillator, and a first electrode 141 and a second electrode 142 arranged to sandwich the piezoelectric element 143. In this embodiment, the first electrode 141 is arranged on the outer periphery side of the piezoelectric element 143, and the second electrode 142 is arranged on the side closer to the central axis Ax than the piezoelectric element 143.

[0022] The piezoelectric element 143 is formed of, for example, ceramics such as PZT (lead zirconate titanate) or a polymer such as PVDF (polyvinylidene fluoride). Instead of the piezoelectric element 143, a MEMS device such as a CMUT (capacitive micro-machined ultrasound transducer) may be used as the ultrasonic oscillator.

[0023] The first electrode 141 and the second electrode 142 are formed of a conductive material such as copper. If the ultrasonic sensor 140 is composed of multiple ultrasonic sensor elements, the first electrode 141 may be provided separately for each of the multiple ultrasonic sensor elements, and the second electrode 142 may be shared by the multiple ultrasonic sensor elements, or each ultrasonic sensor element may be provided with its own second electrode 142. The first electrode 141 is an electrode through which a sound pressure signal is input and output. The potential of the first electrode 141 rises and falls according to the sound pressure signal. The second electrode 142 is a ground electrode. The potential of the second electrode 142 is set to a predetermined reference potential.

[0024] The second electrode 142 is electrically connected to the core wire 110 via a conductive adhesive 158. The first electrode 141 is electrically connected to the lead wire 151 via a conductive adhesive 152. The lead wire 151 is, for example, an enameled wire. The lead wire 151 extends from the connection position with the first electrode 141 along the core wire 110 toward the proximal end. As shown in FIG. 2 , the lead wire 151 is disposed between the core wire 110 and the proximal coil 130, and between the core wire 110 and a non-conductive adhesive 172 (described later). As shown in FIG. 3 , a non-conductive adhesive 159 is disposed between the core wire 110 and the first electrode 141, the conductive adhesive 152, and the lead wire 151. The non-conductive adhesive 159 prevents short circuits between the core wire 110 and the first electrode 141, the conductive adhesive 152, and the lead wire 151. The conductive adhesive 158 and the non-conductive adhesive 159 also function as bonds that secure the ultrasonic sensor 140 to the core wire 110 .

[0025] 2 and 3, a non-conductive adhesive 171 is disposed around the ultrasonic sensor 140. The non-conductive adhesive 171 is filled in the region sandwiched between the proximal end of the distal coil 120 and the distal end of the proximal coil 130 along the longitudinal direction of the main body 102. The non-conductive adhesive 171 covers the ultrasonic transmission / reception surface of the ultrasonic sensor 140. The non-conductive adhesive 171 fixes the ultrasonic sensor 140 and its peripheral members to the core wire 110. The non-conductive adhesive 171 may function as an acoustic matching layer and a backing material.

[0026] 2 , a non-conductive adhesive 172 is disposed on the main body 102 of the guidewire 100 proximal to the proximal coil 130 so as to cover the core wire 110 from the outer periphery. A first device electrode terminal 153 and a second device electrode terminal 157 are provided at the proximal end of the main body 102.

[0027] The second device electrode terminal 157 is a cylindrical electrode terminal that surrounds the outer periphery of the core wire 110 and the non-conductive adhesive 172. The second device electrode terminal 157 is electrically connected to the proximal end of the core wire 110 via a conductive joint 165 provided at the proximal end of the core wire 110. As described above, the core wire 110 is electrically connected to the second electrode 142, and therefore the second device electrode terminal 157 is electrically connected to the second electrode 142 via the core wire 110.

[0028] The first device electrode terminal 153 is disposed closer to the distal end than the second device electrode terminal 157. The first device electrode terminal 153 and the second device electrode terminal 157 are disposed apart from each other in the longitudinal direction of the main body 102. The first device electrode terminal 153 is a cylindrical electrode terminal that surrounds the outer periphery of the core wire 110 and the non-conductive adhesive 172. The first device electrode terminal 153 is electrically connected to the proximal end of the lead wire 151 via a conductive joint 155 provided at the proximal end of the core wire 110. As described above, the lead wire 151 is electrically connected to the first electrode 141, and therefore the first device electrode terminal 153 is electrically connected to the first electrode 141 via the lead wire 151.

[0029] 4 is an explanatory diagram showing the electrical configuration of the guidewire 100. The first electrode 141 is electrically connected to an external electrode 154 of a first device-side electrode terminal 153 via a lead wire 151. The second electrode 142 is electrically connected to an external ground electrode of a second device-side electrode terminal 157 via a core wire 110.

[0030] The potential of the second device-side electrode terminal 157 is set to a predetermined reference potential. As a result, the potential of the second electrode 142 of the ultrasonic sensor 140 electrically connected to the second device-side electrode terminal 157 is also set to the reference potential, and the second electrode 142 functions as a ground electrode. When the ultrasonic sensor 140 transmits ultrasonic waves, the potential of the external electrode 154 included in the first device-side electrode terminal 153 is set to a potential corresponding to the transmission signal. As a result, the potential of the first electrode 141 electrically connected to the first device-side electrode terminal 153 becomes a potential corresponding to the transmission signal, and a voltage is applied to the piezoelectric element 143 to transmit ultrasonic waves. When the ultrasonic sensor 140 receives reflected ultrasonic waves, the potential of the first electrode 141 becomes a potential corresponding to the sound pressure of the received ultrasonic waves, and the potential of the external electrode 154 included in the first device-side electrode terminal 153 electrically connected to the first electrode 141 also becomes a potential corresponding to the sound pressure of the received ultrasonic waves. Based on the electrical signals acquired via the second device side electrode terminal 157 and the first device side electrode terminal 153, the state of the blood vessels is visualized (imaged) by the ultrasonic echo device 320, as will be described later.

[0031] 5 and 6 are explanatory diagrams showing the half-width of ultrasonic waves transmitted by the ultrasonic sensor 140. FIG. 5 shows a cross section of the main body 102 of the guide wire 100 at the position of the ultrasonic sensor 140. FIG. 6 shows an example of the sound pressure distribution of ultrasonic waves transmitted from the ultrasonic sensor 140. As shown in FIG. 6, the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor 140 is maximum in the transmission direction D1 perpendicular to the transmitting / receiving surface of the ultrasonic sensor 140, and the sound pressure changes depending on the angle θa offset from the transmission direction D1. The range of the offset angle θa over which the sound pressure transmitted from the ultrasonic sensor 140 is equal to or greater than half of the maximum value is called the half-width HW.

[0032] The half-width HW of the ultrasonic sensor 140 can be experimentally determined using a sound pressure measuring device. When a simple rectangular diaphragm is used, for example, the half-width HW of the ultrasonic sensor 140 can also be calculated using the following formula (1): In formula (1), a is the sensor width, k is the wave number, γ is the azimuth angle (deviation angle θa), and L is the sound pressure (directivity).

[0033] In this embodiment, the ultrasonic sensor 140 is disposed so that the bending direction D2 of the tip portion 105 of the main body 102 is within a positional range in the transverse cross section of the main body 102 of the guidewire 100 where the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor 140 is equal to or greater than half the maximum value, i.e., within the range of the half-value width HW. The ultrasonic sensor 140 may also be disposed so that the bending direction D2 of the tip portion 105 is within a positional range in the transverse cross section of the main body 102 where the sound pressure of the transmitted ultrasonic waves is equal to or greater than half the maximum value. It is more preferable that the bending direction D2 of the tip portion 105 is within a positional range where the sound pressure is equal to or greater than three-quarters the maximum value. It is even more preferable that the bending direction D2 of the tip portion 105 and the transmission direction D1 of the ultrasonic sensor 140 approximately coincide with each other. This is because the transmission direction D1 is the direction in which the sound pressure of the ultrasonic waves is at its maximum. In this embodiment, the ultrasonic wave transmitting / receiving surface of the ultrasonic sensor 140 faces the positive Y-axis direction, and the transmission direction D1 in which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor 140 is greatest is the positive Y-axis direction. As described above, the bending direction D2 of the tip portion 105 of the main body 102 is the positive Y-axis direction. Therefore, in this embodiment, the bending direction D2 and the transmission direction D1 are approximately aligned. The two directions being approximately aligned are not limited to being strictly aligned, but also include a case in which the angular deviation between the two is within ±1 degree.

[0034] (Configuration of Toruca 200) Figures 7 and 8 are explanatory diagrams that show the outline of the configuration of Toruca 200. Figure 7 shows the external configuration of Toruca 200, and Figure 8 shows the internal configuration of Toruca 200. Toruca 200 is an example of a Toruca and connection section for an elongated medical device.

[0035] The torquer 200 is a device that fixedly supports the proximal end of the guidewire 100, and is used by the operator to advance and retreat and rotate the guidewire 100. The torquer 200 has a main body 220, a support portion 210, and an angle sensor 224.

[0036] The support portion 210 is a member that fixedly supports the proximal end of the guidewire 100. The support portion 210 has a grip portion 211 and an operation portion 212. The grip portion 211 is located at the distal end of the support portion 210 and grips the proximal end of the guidewire 100. The operation portion 212 is a substantially cylindrical portion connected to the proximal end side of the grip portion 211. The operation portion 212 is supported by the main body 220 so as to be rotatable around the axis of the guidewire 100 gripped by the grip portion 211. The operation portion 212 is gripped by the operator's thumb and index finger, for example, and is rotated by the operator. When the operator rotates the operation portion 212, the guidewire 100 gripped by the grip portion 211 rotates around the axis.

[0037] The main body 220 has a housing 225, a bearing 221, a first torquer side electrode terminal 226, a second torquer side electrode terminal 227, a substrate 228, and wiring 229. Hereinafter, the first torquer side electrode terminal 226 and the second torquer side electrode terminal 227 will also be collectively referred to as torquer side electrode terminals 226, 227.

[0038] The housing 225 is a component grasped by the operator. For example, three recesses are provided on the outer surface of the housing 225, and the operator places his / her middle finger, ring finger, and little finger in the recesses and grasps the housing 225 with these three fingers and the palm of his / her hand. The bearing 221 is installed within the housing 225 and rotatably supports the operation unit 212 of the support unit 210. For example, the operator can grasp and fix the housing 225 with the middle finger, ring finger, and little finger and the palm of his / her hand, while grasping and rotating the operation unit 212 with his / her thumb and index finger. The torquer side electrode terminals 226 and 227 are electrode terminals installed within the housing 225. When the guidewire 100 is supported by the support unit 210, the torquer side electrode terminals 226 and 227 are electrically connected to the device side electrode terminals 153 and 157 (see FIG. 2 ) exposed at the proximal end of the guidewire 100. The torquer side electrode terminals 226, 227 can be continuously in contact with the device side electrode terminals 153, 157 even when the guide wire 100 rotates in conjunction with the rotation of the support portion 210. The torquer side electrode terminals 226, 227 are formed of, for example, leaf springs.

[0039] The first torquer side electrode terminal 226 is electrically connected to the first device side electrode terminal 153 by coming into contact with the first device side electrode terminal 153 to which the sound pressure signal is transmitted. The second torquer side electrode terminal 227 is electrically connected to the second device side electrode terminal 157 by coming into contact with the second device side electrode terminal 157 which is at ground potential. The positions of the torquer side electrode terminals 226, 227 in the longitudinal direction of the housing 225 are set to coincide with the positions of the device side electrode terminals 153, 157 of the guide wire 100 attached to the support part 210. Transmission and reception of electrical signals via the torquer side electrode terminals 226, 227 is performed via a substrate 228 and wiring 229 provided in the main body 220.

[0040] The angle sensor 224 is a sensor that measures the rotation angle of the support part 210 relative to the main body 220, and includes a magnet 222 and a magnetic sensor 223. The magnet 222 is attached to the operation part 212 of the support part 210, and rotates as the support part 210 rotates. The magnetic sensor 223 is fixedly attached to the main body 220. The magnetic sensor 223 detects a change in magnetic force corresponding to the rotation of the magnet 222 accompanying the rotation of the support part 210, and detects the rotation angle of the support part 210 relative to the main body 102 based on the change in magnetic force. Because the support part 210 fixedly supports the guidewire 100, measuring the rotation angle of the support part 210 is equivalent to measuring the rotation angle of the guidewire 100. Because the guidewire 100 has the ultrasonic sensor 140 fixedly mounted thereon, measuring the rotation angle of the guidewire 100 is equivalent to measuring the rotation angle of the ultrasonic sensor 140, and is therefore equivalent to measuring the angle in the transmission direction D1 at which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor 140 is at its maximum. The angle measurement result by the angle sensor 224 is transmitted to the ultrasonic echo device 320 (see FIG. 1 ) via a substrate 228 and wiring 229 provided in the main body 220.

[0041] The ultrasonic echo device 320 is a device for controlling the ultrasonic sensor 140 mounted on the guidewire 100. The ultrasonic echo device 320 is an example of a calculation processing unit and a reading unit. A connector 310, which is connected to the wiring 229 of the torquer 200, is connected to the ultrasonic echo device 320. This establishes a signal transmission route between the ultrasonic echo device 320 and the ultrasonic sensor 140 of the guidewire 100. More specifically, the ultrasonic echo device 320 and the first electrode 141 of the ultrasonic sensor 140 are connected via the connector 310, the wiring 229 of the torquer 200, the substrate 228 and the first torquer side electrode terminal 226, the first device side electrode terminal 153 of the guidewire 100, and the lead wire 151. The ultrasonic echo device 320 and the second electrode 142 of the ultrasonic sensor 140 are connected via the connector 310, the wiring 229 of the torquer 200, the substrate 228 and the second torquer side electrode terminal 227, the second device side electrode terminal 157 of the guide wire 100, and the core wire 110. The ultrasonic echo device 320 uses the second electrode 142 of the ultrasonic sensor 140 as a reference potential via the signal transmission route. The ultrasonic echo device 320 sends an electrical signal for transmitting ultrasonic waves to the first electrode 141 of the ultrasonic sensor 140 via the signal transmission route, and receives an electrical signal Rx representing the reflected wave of the ultrasonic waves received by the ultrasonic sensor 140.

[0042] By connecting the connector 310 to the ultrasonic echo device 320, a signal transmission route is further established between the ultrasonic echo device 320 and the angle sensor 224 of the Torca 200. The ultrasonic echo device 320 receives an electrical signal Dx indicating the angle of the transmission direction D1 of the ultrasonic sensor 140 measured by the angle sensor 224 via the signal transmission route.

[0043] The ultrasonic echo device 320 performs information processing to display an image on the display device 330 based on the received electrical signal. FIG. 9 is an explanatory diagram conceptually illustrating information processing by the ultrasonic echo device 320. FIG. 10 is a schematic diagram of an image displayed on the display device 330. As shown in FIG. 9, the ultrasonic echo device 320 performs, for example, A / D conversion processing, filtering processing, detection processing, logarithmic compression processing, and scan conversion (coordinate conversion) processing based on the electrical signal Rx representing the reflected wave of ultrasound received by the ultrasonic sensor 140, to generate image data representing a vascular cross-sectional image. The ultrasonic echo device 320 displays the vascular cross-sectional image on the display device 330 based on the image data. FIG. 10 schematically illustrates a displayed vascular cross-sectional image I10. The display device 330 is an example of a display unit.

[0044] 9 , the ultrasonic echo device 320 further identifies the angle θs of the bending direction D2 of the distal end portion 105 of the guidewire 100 based on the electrical signal Dx indicating the angle of the transmission direction D1 of the ultrasonic sensor 140. As described above, in this embodiment, the bending direction D2 of the distal end portion 105 and the transmission direction D1 of the ultrasonic sensor 140 substantially coincide with each other, and therefore the angle θs of the bending direction D2 is set to be the same as the angle of the transmission direction D1. Based on the identified angle θs of the bending direction D2, the ultrasonic echo device 320 generates image data representing an image Id indicating the bending direction D2 of the distal end portion 105 of the guidewire 100, and displays the image Id indicating the bending direction D2 on the blood vessel cross-sectional image I10 by superimposing it on the display device 330 (see FIG. 10 ).

[0045] By referring to the vascular cross-sectional image I10 shown in FIG. 10 , the operator can grasp the state of the blood vessel and the direction in which the distal end portion 105 of the guidewire 100 extends from the position of the ultrasonic sensor 140 of the guidewire 100 inserted into the blood vessel. First, the center position of the vascular cross-sectional image I10 is the position of the ultrasonic sensor 140. In the vascular cross-sectional image I10, the approximately circular area Ig in the center is the ring-down area. The operator can also grasp the state of the blood vessel from the brightness (reflection intensity). Although details of the ultrasonic reflection intensity and the associated brightness are omitted from the illustration, the area around the area Ig is the vascular cavity area Bl. In the area Bl, the blood is filled, and the ultrasonic reflection intensity is weak, resulting in low brightness. The area around the vascular cavity area Bl is the vascular wall, and the boundary between the vascular cavity and the vascular wall and its vicinity has strong ultrasonic reflection intensity and high brightness. The area of ​​the vascular wall where the ultrasonic reflection intensity is strong is the area Bws. The reflection intensity in the region Bwl, which is the portion of the blood vessel wall outside the region Bws, is weaker than that in the region Bws. In this way, the operator can grasp the distribution of the blood vessel wall.

[0046] In this embodiment, the ultrasonic echo device 320 further displays a so-called M-mode ultrasonic image I20 on the display device 330. The M-mode ultrasonic image I20 is an image with time on the horizontal axis and the intensity (brightness value) of the ultrasonic echo on the vertical axis. When the ultrasonic echo device 320 receives an electrical signal Rx representing a reflected wave of ultrasonic waves received by the ultrasonic sensor 140, it shifts the time series by one step backward and updates the current brightness value to a brightness value based on the latest electrical signal Rx, thereby generating the M-mode ultrasonic image I20.

[0047] FIG. 11 is an explanatory diagram showing an example of a procedure using the vascular cross-sectional image display system 10 of this embodiment. FIG. 11 shows an operation of guiding the guidewire 100 to the true lumen 21 when the guidewire 100 has entered the false lumen 22 of the blood vessel 20. As shown in the left column of FIG. 11 , the operator rotates the guidewire 100 by rotating the support portion 210 of the torquer 200. As a result, a vascular cross-sectional image I10 captured by the ultrasonic sensor 140 of the guidewire 100 is displayed on the display device 330. The operator references the displayed vascular cross-sectional image I10 to confirm that the guidewire 100 has passed through the false lumen 22. The operator references an image Id showing the bending direction D2 of the distal end portion 105 of the guidewire 100, displayed in the vascular cross-sectional image I10, to grasp the bending direction D2 of the distal end portion 105.

[0048] 11 , while viewing the image Id showing the bending direction D2 of the distal end portion 105, the operator rotates the guidewire 100 to orient the bending direction D2 of the distal end portion 105 toward the true lumen 21. As a result, the bending direction D2 of the distal end portion 105 becomes the direction from the false lumen 22 toward the true lumen 21.

[0049] 11 , the operator advances the guidewire 100 and guides the distal end portion 105 from the false lumen 22 to the true lumen 21. After this guidance, the operator rotates the guidewire 100 and captures an image with the ultrasonic sensor 140 to generate a vascular cross-sectional image I10, and then refers to the vascular cross-sectional image I10 to confirm that the distal end portion 105 has been guided to the true lumen 21. In this way, the operator can reliably guide the guidewire 100 to the true lumen 21 even if the guidewire 100 has entered the false lumen 22.

[0050] (Manufacturing Method of Guidewire 100) Fig. 12 is an explanatory diagram showing an example of a manufacturing method of guidewire 100. The manufacturing of guidewire 100 is carried out using manufacturing apparatus 80. First, an operator prepares guidewire 100 having main body 102 and ultrasonic sensor 140 fixedly mounted on main body 102. At this stage, main body 102 is not bent.

[0051] The operator captures an image of the ultrasonic sensor 140 and the main body 102 using an imaging device 82, such as a microscope, from a direction facing the ultrasonic transmission / reception surface of the ultrasonic sensor 140 (from above in the example of FIG. 12 ), and displays the image on a display device 83. This imaging direction is the direction in which the ultrasonic sensor 140 occupies the largest proportion of the captured image. The operator presses a fixing pin 81 against an arbitrary position on the main body 102 in the longitudinal direction, distal to the mounting position of the ultrasonic sensor 140, and bends the distal end portion 105 using a jig so that the outline of the main body 102 in the image remains straight. The fixing pin 81 is an example of a fixing member. The bending position where the fixing pin 81 is placed is the bending point 104.

[0052] After bending the main body 102, or while bending the main body 102, the operator displays an image of the main body 102 captured by the imaging device 82 from a direction parallel to the longitudinal direction of the base 106 of the main body 102 (the Z-axis direction in the example of FIG. 12 ) on the display device 83. The operator refers to the image and checks whether the transmission direction D1 of the ultrasonic sensor 140 and the bending direction D2 of the tip portion 105 are aligned in the transverse cross section of the main body 102.

[0053] 13 and 14 are explanatory diagrams showing the state of the guidewire 100 when the transmission direction D1 and the bending direction D2 are aligned. Fig. 13 shows an example of an image of the ultrasonic sensor 140 and the main body 102 captured from a direction facing the ultrasonic transmission / reception surface of the ultrasonic sensor 140 (from above in Fig. 12). Fig. 14 shows an example of an image of the main body 102 captured from a direction parallel to the longitudinal direction of the base 106 (the Z-axis direction). If the outline of the main body 102 is maintained linear in the image shown in Fig. 13 before and after the operation of bending the main body 102, the transmission direction D1 and the bending direction D2 will be aligned.

[0054] 15 and 16 are explanatory diagrams showing the state of the guidewire 100 when the transmission direction D1 and the bending direction D2 do not coincide. Fig. 15 shows an example of an image of the ultrasonic sensor 140 and the main body 102 captured from a direction facing the ultrasonic transmission / reception surface of the ultrasonic sensor 140 (from above in Fig. 12 ). Fig. 16 shows an example of an image of the main body 102 captured from a direction parallel to the longitudinal direction of the base 106 (the Z-axis direction). If the outline of the main body 102 is not maintained as a straight line in the image shown in Fig. 15 before and after bending the main body 102, the transmission direction D1 and the bending direction D2 will not coincide, resulting in a deviation angle Δθ between them.

[0055] The worker checks whether the transmission direction D1 and the bending direction D2 are aligned. If the transmission direction D1 and the bending direction D2 are aligned, the manufacturing process is complete. If the transmission direction D1 and the bending direction D2 are not aligned, the worker measures the deviation angle Δθ between the transmission direction D1 and the bending direction D2 and records the value of the deviation angle Δθ in the memory 312 ( FIG. 1 ) disposed in the connector 310. This completes the manufacturing process. If the transmission direction D1 and the bending direction D2 are aligned, the worker may write zero as the value of the deviation angle Δθ in the memory 312. If zero is written as the default value of the deviation angle Δθ in the memory 312 and the transmission direction D1 and the bending direction D2 are not aligned, the worker may overwrite the value of the deviation angle Δθ. The memory 312 is, for example, a non-volatile ROM. The memory 312 is an example of a storage member.

[0056] When generating the vascular cross-sectional image I10, the ultrasonic echo device 320 reads the value of the deviation angle Δθ from the memory 312 of the connector 310. The ultrasonic echo device 320 identifies the bending direction D2 of the distal end portion 105 based on the read value of the deviation angle Δθ and the rotation angle of the guidewire 100 acquired from the angle sensor 224, i.e., the angle of the transmission direction D1 of the ultrasonic sensor 140, and generates and displays an image Id indicating the bending direction D2. As a result, even when the transmission direction D1 and the bending direction D2 do not coincide, the image Id indicating the bending direction D2 of the distal end portion 105 can be displayed in the vascular cross-sectional image I10 in the same way as when the transmission direction D1 and the bending direction D2 coincide.

[0057] (Effects of the Present Embodiment) As described above, in the guidewire 100, a blood vessel cross-sectional image is generated by the ultrasonic sensor 140 included in the guidewire 100. Furthermore, in the guidewire 100, the bending direction D2 of the distal end portion 105 is close to the transmission direction D1 in which the sound pressure of the ultrasound transmitted from the ultrasonic sensor 140 is at its maximum. Therefore, by referring to the blood vessel cross-sectional image, the operator can grasp the position of the blood vessel and the position and orientation of the guidewire 100 (e.g., the orientation of the distal end portion 105) with a certain degree of accuracy. Therefore, the position and orientation of the guidewire 100 in the blood vessel can be grasped with a relatively simple device configuration without using an X-ray device or an IVUS device.

[0058] In Torca 200, when support section 210 rotates in response to a rotation operation by the operator, the rotation angle of support section 210 measured by angle sensor 224 is the same as the rotation angle of guidewire 100. Therefore, Torca 200 can accurately measure the amount of rotation of guidewire 100 in response to a rotation operation by the operator.

[0059] In the manufacturing method of guidewire 100, distal end portion 105, which is the portion of main body 102 distal to bending point 104, is bent at an arbitrary position distal to the mounting position of ultrasonic sensor 140 in the longitudinal direction of main body 102 so that the outline of main body 102 in the image remains straight. This makes it possible to manufacture guidewire 100 in which bending direction D2 of distal end portion 105 is close to transmission direction D1 in which the sound pressure of ultrasonic waves transmitted from ultrasonic sensor 140 is maximized. In this manufacturing method, the manufacturing accuracy of guidewire 100 can be controlled by checking whether bending direction D2 of distal end portion 105 coincides with transmission direction D1 of ultrasonic sensor 140.

[0060] In the method for manufacturing the guidewire 100, when the transmission direction D1 of the ultrasonic sensor 140 does not match the bending direction D2 of the distal end portion 105, the deviation angle Δθ between the transmission direction D1 and the bending direction D2 is measured and the deviation angle Δθ is written to a memory 312 attached to the guidewire 100. As a result, even when the bending direction D2 of the distal end portion 105 does not match the transmission direction D1 of the ultrasonic sensor 140, correction is performed using the deviation angle Δθ written to the memory 312, thereby realizing an image display similar to that when the bending direction D2 matches the transmission direction D1.

[0061] Manufacturing apparatus 80 used in the manufacturing method of guidewire 100 has a fixing pin 81, an imaging device 82, and a display device 83. Fixing pin 81 is a member for holding bending point 104 in main body 102. Imaging device 82 photographs guidewire 100. Display device 83 displays the image obtained by imaging device 82. Using manufacturing apparatus 80 of this embodiment, guidewire 100 can be manufactured according to the manufacturing method described above.

[0062] The vascular cross-sectional image display system 10 includes a Torca 200, an ultrasonic echo device 320, and a display device 330. A guidewire 100 is detachably attached to the Torca 200. The ultrasonic echo device 320 generates image data by performing arithmetic processing on ultrasound data acquired from the guidewire 100 via the Torca 200. The ultrasonic echo device 320 generates image data indicating the bending direction D2 of the distal end portion 105 of the guidewire 100. The display device 330 displays a cross-sectional image of the blood vessel into which the guidewire 100 has been inserted, based on the image data. The vascular cross-sectional image display system 10 of this embodiment can display an image that allows the position of the blood vessel and the position and posture of the guidewire 100 (for example, the orientation of the distal end portion 105) to be grasped.

[0063] In the vascular cross-sectional image display system 10, the ultrasonic echo device 320 reads, from a memory 312 attached to the guidewire 100, deviation angle data between the transmission direction D1 in which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor 140 is maximized in the transverse cross section of the main body 102 of the guidewire 100 and the bending direction D2 of the tip section 105. Based on the deviation angle data, the ultrasonic echo device 320 generates image data indicating the bending direction D2 of the tip section 105 of the guidewire 100. The vascular cross-sectional image display system 10 of this embodiment can display an image that allows the position and posture of the guidewire 100 to be grasped, regardless of the relationship between the transmission direction D1 of the ultrasonic sensor 140 and the bending direction D2 of the tip section 105.

[0064] 17 shows a schematic diagram of the configuration of Toruca 200a, which is partially different in form from Toruca 200. In the following, the same components of Toruca 200a as those of Toruca 200 are denoted by the same reference numerals and descriptions thereof will be omitted where appropriate.

[0065] The torquer 200a includes a distal torquer 200d and a proximal torquer 200p. The distal torquer 200d and the proximal torquer 200p are separated from each other. When the torquer 200a is in use, the distal torquer 200d is positioned closer to the distal end than the proximal torquer 200p.

[0066] The distal torquer 200d has a main body 220d, a support portion 210d, and an angle sensor 224. The support portion 210d is a member that fixedly supports the guidewire 100. The support portion 210d fixedly supports any portion of the guidewire 100 that is distal to the proximal end. The support portion 210d has a grip portion 211d and an operation portion 212d. The grip portion 211d is located at the distal end of the support portion 210d and grips the guidewire 100. The operation portion 212d is a substantially cylindrical portion connected to the proximal end side of the grip portion 211d. The operation portion 212d is supported by the main body 220d so as to be rotatable around the axis of the guidewire 100 gripped by the grip portion 211d. The operation portion 212d is gripped by the operator's thumb and index finger, for example, and is rotated by the operator. When the operator performs a rotation operation on the operation portion 212d, the guide wire 100 gripped by the grip portion 211d rotates around its axis.

[0067] The main body 220d includes a housing 225d, a bearing 221d, a substrate 228d, and wiring 229d. The housing 225d is a generally cylindrical member that is grasped by the operator, and has, for example, three recesses on its outer surface. The operator places, for example, their middle finger, ring finger, and little finger in the three recesses and grasps the housing 225d with three fingers and their palm. The bearing 221d is installed within the housing 225d and rotatably supports the operation unit 212d of the support unit 210d. The operator can grasp and rotate the operation unit 212d with their thumb and index finger while grasping and fixing the housing 225d with three fingers and their palm.

[0068] The angle sensor 224 is a sensor that measures the rotation angle of the support part 210d relative to the main body 220d, and includes a magnet 222 and a magnetic sensor 223. The magnet 222 is attached to the operation part 212d of the support part 210d and rotates with the rotation of the support part 210d. The magnetic sensor 223 is fixedly attached to the main body 220d. The magnetic sensor 223 detects a change in the magnetic field corresponding to the rotation of the magnet 222 accompanying the rotation of the support part 210d, and detects the rotation angle of the support part 210d relative to the main body 220d based on the change in the magnetic field. Because the support part 210d fixedly supports the guidewire 100, measuring the rotation angle of the support part 210d is equivalent to measuring the rotation angle of the guidewire 100. Because the guidewire 100 has the ultrasonic sensor 140 fixedly mounted thereon, measuring the rotation angle of the guidewire 100 is equivalent to measuring the rotation angle of the ultrasonic sensor 140, and is therefore equivalent to measuring the angle in the transmission direction D1 at which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor 140 is at its maximum. The angle measurement result by the angle sensor 224 is transmitted to the ultrasonic echo device 320 (see FIG. 1 ) via a substrate 228d and wiring 229d provided in the main body 220d.

[0069] The proximal torquer 200p has a main body 220p and a support portion 210p. The support portion 210p is a member that fixedly supports the proximal end portion of the guidewire 100. The support portion 210p is supported by the main body 220p so as to be rotatable around the axis of the guidewire 100 supported by the support portion 210p.

[0070] The main body 220p has a housing 225p, a bearing 221p, a first torquer side electrode terminal 226, a second torquer side electrode terminal 227, a substrate 228p, and wiring 229p. The housing 225p is a cylindrical member. The bearing 221p is installed within the housing 225p and rotatably supports the support portion 210p. When the guidewire 100 is rotated by the operator's operation of the distal torquer 200p, the support portion 210p that supports the guidewire 100 at the proximal torquer 200p rotates relative to the housing 225p. The torquer side electrode terminals 226, 227 are electrode terminals installed within the housing 225p, and are electrically connected to the device side electrode terminals 153, 157 (see FIG. 2) exposed at the proximal end of the guidewire 100 when the guidewire 100 is supported by the support portion 210p. The torquer side electrode terminals 226, 227 can be continuously in contact with the device side electrode terminals 153, 157 even when the guide wire 100 rotates. The torquer side electrode terminals 226, 227 are formed of, for example, leaf springs. The main body 220p is an example of an electrode terminal portion.

[0071] The first torquer side electrode terminal 226 is electrically connected to the first device side electrode terminal 153 by coming into contact with the first device side electrode terminal 153 to which the sound pressure signal is transmitted. The second torquer side electrode terminal 227 is electrically connected to the second device side electrode terminal 157 by coming into contact with the second device side electrode terminal 157 which is at ground potential. The positions of the torquer side electrode terminals 226, 227 in the longitudinal direction of the housing 225p are set to coincide with the positions of the device side electrode terminals 153, 157 of the guide wire 100 attached to the support portion 210p. Transmission and reception of electrical signals via the torquer side electrode terminals 226, 227 is performed via a substrate 228p and wiring 229p provided in the main body 220p.

[0072] As described above, in the torquer 200a, the main body 220p of the base-end torquer 200p, which has torquer electrode terminals 226, 227 electrically connected to the device-side electrode terminals 153, 157 provided on the guidewire 100, is separated from the main body 220d of the distal torquer 200d. This improves the degree of freedom in the placement of the support portion 210d of the distal torquer 200d, which is rotated by the operator, thereby improving the operability of the torquer 200a. Depending on the design, the device-side electrode terminals 153, 157 are often located at the base end of the guidewire 100. In this case, for example, the main body 220p of the base-end torquer 200p can be located near the device-side electrode terminals 153, 157, while the distal torquer 200d, which has the support portion 210d through which the operator directly applies torque to the guidewire 100, can be located more distally. This allows the length of the portion of the guidewire 100 from the base end of the catheter to the distal torquer 200d to be shortened, thereby preventing a decrease in the operability of the torquer 200a due to bending of that portion.

[0073] 18 is an explanatory diagram schematically illustrating the configuration of a vascular cross-sectional image display system 10b according to a second embodiment. In the following, the same components of the display system 10b as those of the vascular cross-sectional image display system 10 according to the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

[0074] The display system 10b includes a guidewire 100b. Unlike the guidewire 100 of the first embodiment, the guidewire 100b does not have a bent distal end portion and is substantially straight throughout its entire length.

[0075] The display system 10b, like the display system 10 of the first embodiment, includes an ultrasonic echo device 320 and a display device 330. The ultrasonic echo device 320 receives, via a predetermined signal transmission route, an electrical signal Rx representing a reflected wave of ultrasonic waves received by the ultrasonic sensor 140 and an electrical signal Dx indicating the angle of the transmission direction D1 of the ultrasonic sensor 140 measured by the angle sensor 224. The ultrasonic echo device 320 generates image data representing a vascular cross-sectional image based on the received electrical signals Rx and Dx, and causes the display device 330 to display the vascular cross-sectional image based on the image data.

[0076] FIG. 19 is an explanatory diagram schematically illustrating a vascular cross-sectional image I10 displayed on the display device 330. The M-mode ultrasound image I20 shown in FIG. 10 is omitted in FIG. 19 , and the same components as those in FIG. 10 are denoted by the same reference numerals, and their description will be omitted where appropriate. The position of the ultrasonic sensor 140 is indicated in the center of the vascular cross-sectional image I10. A specific region R1 in the vascular cross-sectional image I10 displays a real-time image of the vascular cross-section at the current time (hereinafter also referred to as the "current image I1"). A region other than the specific region R1 in the vascular cross-sectional image I10 (hereinafter also referred to as the "remaining region R2") displays a previous image of the vascular cross-section at a previous time (hereinafter also referred to as the "previous image I2"). However, if there is no data for the previous image I2, this is a region where no ultrasound was transmitted or received, and therefore a region RN is displayed in which no ultrasound reflection intensity is displayed. The specific region R1 is a wide region indicating depth information including the transmission direction D1 of ultrasound from the center of the vascular cross-sectional image I10. The depth information is information that represents the reflection intensity of the ultrasonic wave along the transmission direction D1 as brightness.

[0077] When the transmission direction D1 of the ultrasonic sensor 140 changes with the rotation of the guidewire 100b, the position of the specific region R1 in the vascular cross-sectional image I10 also changes accordingly. In this embodiment, the specific region R1 is a substantially fan-shaped region that is line-symmetrical with respect to the transmission direction D1 of the ultrasonic waves from the ultrasonic sensor 140. As described above, since a substantially circular ring-down region Ig exists in the center of the vascular cross-sectional image I10, the specific region R1 is, strictly speaking, a substantially trapezoidal region. The width of the specific region R1 along the circumferential direction may be the minimum width that can be displayed as an image (e.g., the width of one pixel). In other words, the specific region R1 may be linear. In the vascular cross-sectional image I10, the central angle of the substantially fan-shaped specific region R1 can be variably set. The central angle of the specific region R1 can be set according to the operator's instructions. The central angle of the specific region R1 may also be set automatically. The central angle of the specific region R1 may be greater than 0° and less than 30°, greater than 3° and less than 25°, or greater than 5° and less than 20°. The central angle of the specific region R1 may be set within a range in which the sound pressure of the ultrasound transmitted from the ultrasonic sensor 140 is greater than or equal to half of the maximum value. In this embodiment, a contour image L1 indicating the contour of the specific region R1 is also displayed in the vascular cross-sectional image I10. By referring to the vascular cross-sectional image I10, the operator can grasp the state of the blood vessel over a wide range, including the specific region R1 and the remaining region R2, and can also grasp the direction in which the ultrasonic sensor 140 is facing. The ultrasonic echo device 320 generates image data based on the electrical signals Rx and Dx so that the vascular cross-sectional image I10 can be displayed.

[0078] A vascular cross-sectional image display system already on the market collects the reflected ultrasound intensity in the scanning direction while rotating a probe with an ultrasound sensor attached to the tip inside the blood vessel, and displays the vascular cross-section from the collected and stored data when the collection of the reflected ultrasound intensity for one rotation (360°) is completed. On the other hand, in this embodiment, vascular information at the position of the ultrasound sensor of the guidewire can be obtained in real time, and the posture of the guidewire can be easily grasped based on the information from the ultrasound sensor, making it possible to advance the guidewire to the target site such as the true lumen 21 (see Figure 11).

[0079] The ultrasonic echo device 320 of this embodiment executes processing to suppress the occurrence of artifacts called NURD (Non-uniform Rotational Distortion) caused by a so-called initial delay.

[0080] The operator rotates the proximal end of the guidewire 100b, which is fixedly supported by the torquer 200, by rotating the torquer 200. At this time, due to factors such as frictional resistance within the blood vessel or the presence of gaps in the coils included in the guidewire 100b, the distal end of the guidewire 100b, on which the ultrasonic sensor 140 is mounted, may not rotate in immediate response to the rotation of the proximal end, resulting in a delay in the rotation of the distal end (hereinafter simply referred to as "initial delay" or "initial delay Δθ"). Figure 20 is a graph conceptually illustrating the initial delay. In this graph, the horizontal axis represents the rotation angle θp of the proximal end of the guidewire 100b, and the vertical axis represents the rotation angle θd of the distal end of the guidewire 100b, showing the relationship between them.

[0081] As shown in FIG. 20 , even if the operator rotates the proximal end of the guidewire 100b to increase the rotation angle θp from the angle θ0 at the start time t0, the rotation angle θd of the distal end of the guidewire 100b does not increase until the specific time t1 at which the distal end of the guidewire 100b begins to rotate. If the operator increases the rotation angle θp beyond the angle θ1 after the specific time t1, the rotation angle θd increases. The start time t0 is the time at which the proximal end starts to rotate in one direction (e.g., clockwise). The start time t0 also includes the time at which the rotation is reversed from the other direction (e.g., counterclockwise) to the above-mentioned one direction. The increase in the rotation angle θp during the period from the start time t0 to the specific time t1 is the initial delay Δθ. The angle sensor 224 (see, for example, FIG. 17 ) detects the rotation angle of the proximal end, but not the rotation angle of the distal end where the ultrasonic sensor 140 is provided. Therefore, when the vascular cross-sectional image I10 is updated based on the signal from the angle sensor 224 during the period from the start time t0 to the specific time t1, NURD occurs because the vascular cross-sectional image I10 is updated based on the signal from the ultrasonic sensor 140, which has not yet actually rotated.

[0082] The ultrasonic echo device 320 executes a process for suppressing the occurrence of NURD. FIG. 21 is a flowchart illustrating this process. The ultrasonic echo device 320 detects that rotation of the proximal end of the guidewire 100b has begun based on an electrical signal Dx acquired from the angle sensor 224 provided in the torquer 200 (S110). The ultrasonic echo device 320 stores the ultrasonic transmission direction D1 of the ultrasonic sensor 140 at the start time t0 when rotation of the proximal end of the guidewire 100b began. At the start time t0, the ultrasonic echo device 320 displays a predetermined symbol in the vascular cross-sectional image I10 along a start line indicating the ultrasonic transmission direction D1 at the start time t0. The symbol may be an image showing a vascular cross-section of a specific region R1, a contour image L1 of the specific region R1, a simple line image, or the like.

[0083] The ultrasonic echo device 320 determines whether the rotation angle θd is zero (S120). This determination is made, for example, based on the electrical signal Dx acquired from the angle sensor 224, by determining whether the rotation angle θp has reached a threshold angle corresponding to the initial motion delay Δθ. If the rotation angle θp has not reached the threshold angle, the rotation angle θd is determined to be zero. If the rotation angle θp has reached the threshold angle, the rotation angle θd is determined to be non-zero, i.e., rotation of the distal end portion has started. The threshold angle may be set to a fixed value or may be manually set by the operator. The determination may be made using the electrical signal Rx acquired from the ultrasonic sensor 140. That is, if there is no significant change in the electrical signal Rx that is equal to or greater than the threshold, the rotation angle θd is determined to be zero. If there is a significant change in the electrical signal Rx that exceeds the threshold, the rotation angle θd is determined to be non-zero, i.e., rotation of the distal end portion has started.

[0084] If the ultrasonic echo device 320 determines that the rotation angle θd is zero (S120: YES), it maintains the position of the symbol in the vascular cross-sectional image I10 without changing it (S130). In this case, the position of the specific region R1 does not change in the vascular cross-sectional image I10. On the other hand, the image within the specific region R1 may be updated. If the ultrasonic echo device 320 determines that the rotation angle θd is not zero (S120: NO), it starts updating the vascular cross-sectional image I10 based on the electrical signals Rx and Dx received from the ultrasonic sensor 140 and the angle sensor 224 (S140). More specifically, the ultrasonic echo device 320 displays symbols such as the image of the specific region R1 and the contour image L1 along a line rotated by the rotation angle θd from the start line indicating the ultrasonic transmission direction D1 at the start time t0 based on the signals received from the ultrasonic sensor 140 and the angle sensor 224. That is, the ultrasonic echo device 320 updates the vascular cross-sectional image I10, including changing the position of the symbol. The rotation angle θd can be determined based on the rotation angle θp after the specific time t1. For example, the rotation angle θd may be determined to be equal to the increase in the rotation angle θp after the specific time t1.

[0085] (Modifications) The technology disclosed in this specification is not limited to the above-described embodiments, and can be modified into various forms without departing from the spirit thereof, for example, the following modifications are also possible.

[0086] The configuration of the guidewire 100 in the above embodiment is merely an example and various modifications are possible. For example, the guidewire 100 may not have at least one of the distal coil 120 and the proximal coil 130. The guidewire 100 may have another coil (for example, an inner layer coil arranged closer to the central axis Ax than the distal coil 120 and the proximal coil 130).

[0087] The first electrode 141 of the ultrasonic sensor 140 may be electrically connected to the first device side electrode terminal 153 via a conductive path other than a lead wire. The second electrode 142 of the ultrasonic sensor 140 may be electrically connected to the core wire 110 via a lead wire or another conductive path. The second electrode 142 of the ultrasonic sensor 140 may be electrically connected to the second device side electrode terminal 157 via another conductive path, not via the core wire 110. The guidewire 100 may have another electrical element instead of or in addition to the ultrasonic sensor 140. The torquer side electrode terminals 226, 227 of the torquer 200 may be electrically connected to the other electrical element of the guidewire 100. The non-conductive adhesive 171 covering the ultrasonic transmission / reception surface of the ultrasonic sensor 140 may be flat, not curved.

[0088] The configuration of the Torca 200 in the above embodiment is merely an example and can be modified in various ways. For example, the angle sensor 224 of the Torca 200 is not limited to being configured by the magnet 222 and the magnetic sensor 223, and may be another type of angle sensor.

[0089] The configuration of the vascular cross-sectional image display system 10 in the above embodiment is merely an example and can be modified in various ways. For example, the memory 312 that stores the deviation angle Δθ between the bending direction D2 of the distal end portion 105 and the transmission direction D1 of the ultrasonic sensor 140 may be disposed in a device other than the connector 310 (e.g., the torquer 200). A device that transmits and receives information wirelessly, such as an RF tag, may be used as the storage member that stores the deviation angle Δθ. The vascular cross-sectional image display system 10 may include a medical device other than the guidewire 100 as the elongated medical device.

[0090] In the second embodiment, the specific region R1 of the vascular cross-sectional image I10 may have a shape other than a sector shape. For example, the specific region R1 may have a substantially rectangular shape. Portions of the specific region R1 where real-time image data generated based on signals acquired from the ultrasonic sensor 140 do not exist may be complemented by filling or the like. The display of the vascular cross-sectional image I10 in the second embodiment may be similarly performed in the vascular cross-sectional image display system 10 of the first embodiment, i.e., in the vascular cross-sectional image display system 10 having a guidewire 100 with a bent distal end portion.

[0091] The guide wire to be used in the vascular cross-sectional image display system of the second embodiment can be used with either a bent or straight tip shape, as long as the ultrasonic transmission / reception surface of the ultrasonic sensor faces the outer periphery of the guide wire in its cross section and the direction of ultrasonic transmission faces radially outward in the cross section.

[0092] The manufacturing method of the guidewire 100 in the above embodiment is merely an example and various modifications are possible. For example, a method for manufacturing the guidewire 100 may be employed in which the guidewire 100 having the main body 102 and the ultrasonic sensor 140 is prepared, an image of the ultrasonic sensor 140 and the main body 102 captured from a direction facing the side of the ultrasonic sensor 140 is displayed, and a distal end portion 105 of the main body 102 is bent at an arbitrary position (bending point 104) distal to the mounting position of the ultrasonic sensor 140 in the longitudinal direction of the main body 102. This imaging direction is a direction in which the proportion of the area occupied by the ultrasonic sensor 140 in the captured image is minimized. This manufacturing method also makes it possible to manufacture a guidewire 100 in which the bending direction D2 of the distal end portion 105 is close to the transmission direction D1 in which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor 140 is maximized.

[0093] As a manufacturing method of the guidewire 100, a method may be adopted in which the bending direction D2 of the distal end portion 105 and the transmission direction D1 of the ultrasonic sensor 140 are intentionally made to differ by a predetermined angle (for example, 90 degrees or 180 degrees) and the angle of difference Δθ between them is written to the memory 312. The vascular cross-sectional image display system 10 of this embodiment is used at the location where the operator uses the guidewire 100, but it is also possible to use an apparatus that performs functions equivalent to the vascular cross-sectional image display system 10 together with the manufacturing apparatus 80 for the guidewire 100.

[0094] In the method of manufacturing the guidewire 100, when bending the distal end portion 105 of the main body 102, it is not necessarily necessary to display an image of the guidewire 100.

[0095] In the above embodiment, the guidewire 100 for treating a lesion in a blood vessel has been described as an example. The technology disclosed in this specification is similarly applicable to general devices, systems, and methods using elongated medical devices for treating a lesion in a biological lumen.

Claims

1. A guidewire (100) comprising: an elongated main body (102) having a distal end portion (105) bent at a bending point (104) that is the proximal end of the distal end portion (105); and an ultrasonic sensor (140) fixedly mounted to the main body (102) so that an ultrasonic transmission / reception surface faces outward in a cross section of the main body (102), wherein the ultrasonic sensor (140) is located near the bending point (104) in the main body (102) and at a bending root portion (107) that is proximal to the bending point (104), and wherein the ultrasonic sensor (140) is disposed so that the bending direction (D2) of the distal end portion (105) is within a positional range in the cross section of the main body (102) where the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor (140) is equal to or greater than half of the maximum value.

2. A guide wire (100) as set forth in claim 1, wherein the tip of the ultrasonic sensor (140) is located within a range from the bending point (104) to a position 20 mm away from the base end along the longitudinal direction of the main body (102).

3. A guide wire (100) according to claim 1 or claim 2, wherein the ultrasonic sensor (140) is arranged so that the bending direction (D2) of the tip portion (105) is within a positional range in which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor (140) is equal to or greater than half the maximum value in the cross section of the main body (102).

4. A guide wire (100) according to any one of claims 1 to 3, wherein, in a cross section of the main body (102), the bending direction (D2) of the tip portion (105) and the transmission direction (D1) in which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor (140) is maximum are substantially the same.

5. A guidewire (100) according to any one of claims 1 to 4, wherein the body (102) has a core wire (110), and the ultrasonic sensor (140) is fixedly supported on the core wire (110).

6. A torquer (200, 200a) for an elongated medical device, comprising: a main body (220, 220d); a support part (210, 210d) that fixedly supports the elongated medical device (100) and is supported by the main body (220, 220d) so as to be rotatable around the axis of the elongated medical device (100) in response to a rotation operation by an operator; and an angle sensor (224) that measures the rotation angle of the support part (210, 210d) relative to the main body (220, 220d).

7. A torquer (200, 200a) for an elongated medical device as set forth in claim 6, wherein the support portion (210, 210d) includes: a gripping portion (211, 211d) for gripping the elongated medical device (100); and an operating portion (212, 212d) for fixedly supporting the gripping portion (211, 211d) and for receiving rotational operation by the operator.

8. A torquer (200, 200a) for an elongated medical device as set forth in claim 6 or claim 7, wherein the angle sensor (224) includes: a magnet (222) provided on one of the support portion (210, 210d) and the main body (220, 220d); and a magnetic sensor (223) provided on the other of the support portion (210, 210d) and the main body (220, 220d).

9. A torquer (200) for an elongated medical device as set forth in any one of claims 6 to 8, wherein the main body (220) has torquer side electrode terminals (226, 227) that can be continuously in contact with device side electrode terminals (153, 157) exposed at the base end of the elongated medical device (100) when the elongated medical device (100) supported by the support part (210) rotates in conjunction with the rotation of the support part (210).

10. A torquer (200) for an elongated medical device as described in claim 9, wherein the torquer side electrode terminals (226, 227) include: a first torquer side electrode terminal (226) that can come into contact with a first device side electrode terminal (153) of the device side electrode terminals (153, 157) to which a fluctuating electrical signal is transmitted; and a second torquer side electrode terminal (227) that can come into contact with a second device side electrode terminal (157) of the device side electrode terminals (153, 157) that is set to ground potential.

11. A torquer (200a) for a long medical device as described in any one of claims 6 to 8, wherein the angle sensor (224) is provided on the main body (220d), and the torquer (200a) further comprises an electrode terminal portion (220p) separated from the main body (220d), and the electrode terminal portion (220p) has torquer side electrode terminals (226, 227) that are electrically connected to device side electrode terminals (153, 157) provided on the long medical device (100).

12. A method for manufacturing a guidewire (100), comprising: preparing a guidewire (100) having an elongated main body (102) and an ultrasonic sensor (140) fixedly mounted on the main body (102) so that the ultrasonic transmission / reception surface faces the outer periphery in a cross section of the main body (102); and bending a tip portion (105) of the main body (102) that is a portion of the main body (102) that is distal from an arbitrary position (104) on the main body (102) that is distal from the arbitrary position (104) on the main body (102) so that the outline of the main body (102) remains linear.

13. A method for manufacturing a guide wire (100) as set forth in claim 12, comprising: displaying an image of the ultrasonic sensor (140) and the main body (102) taken from a direction opposite the ultrasonic transmission / reception surface of the ultrasonic sensor (140); and bending the tip portion (105) so that the outline of the main body (102) remains straight in the image.

14. A method for manufacturing a guidewire (100), comprising the steps of: preparing a guidewire (100) having an elongated main body (102) and an ultrasonic sensor (140) fixedly mounted on the main body (102) so that an ultrasonic transmission / reception surface faces the outer periphery in a cross section of the main body (102); displaying an image of the ultrasonic sensor (140) and the main body (102) taken from a direction facing a side of the ultrasonic sensor (140); and bending a tip portion (105) of the main body (102) at an arbitrary position (104) distal to the mounting position of the ultrasonic sensor (140) in the longitudinal direction of the main body (102), the tip portion being a portion of the main body (102) distal to the arbitrary position (104).

15. A method for manufacturing a guidewire (100) according to any one of claims 12 to 14, comprising: after bending the main body (102) or while bending the main body (102), displaying an image of the main body (102) taken from a direction parallel to the longitudinal direction of a portion of the main body (102) that is proximal to the arbitrary position (104); and confirming whether the transmission direction (D1) in which the sound pressure of the ultrasonic waves transmitted from the ultrasonic sensor (140) is maximum coincides with the bending direction (D2) of the tip portion (105) in a cross section of the main body (102).

16. A method for manufacturing a guidewire (100) according to claim 15, wherein, when the transmission direction (D1) and the bending direction (D2) do not coincide, a deviation angle between the transmission direction (D1) and the bending direction (D2) is measured, and the deviation angle is written in a memory member (312) attached to the guidewire (100).

17. A manufacturing device (80) for a guide wire (100) for the manufacturing method described in any one of claims 12 to 16, comprising: a fixing member (81) for holding the arbitrary position (104) on the main body (102); an imaging device (82) for photographing the guide wire (100); and a display device (83) for displaying an image obtained by imaging with the imaging device (82).

18. A blood vessel cross-sectional image display system (10) comprising: a main body (102) whose tip portion (105) is bent at a bending point (104) which is the base end of the tip portion (105); and a connecting portion (200) to which a guidewire (100) having an ultrasonic sensor (140) fixedly mounted on the main body (102) so that an ultrasonic transmission / reception surface faces the outer periphery in a cross section of the main body (102) is detachably attached; an arithmetic processing unit (320) which generates image data by arithmetic processing of ultrasonic data acquired from the guidewire (100) via the connecting portion (200), the arithmetic processing unit (320) generating the image data indicating the bending direction (D2) of the tip portion (105) of the guidewire (100); and a display unit (330) which displays a cross-sectional image of a blood vessel into which the guidewire (100) is inserted based on the image data.

19. A blood vessel cross-sectional image display system (10) according to claim 18, further comprising a reading unit (320) capable of reading, from a memory member (312) attached to the guide wire (100), deviation angle data between the transmission direction (D1) in which the sound pressure of the ultrasound transmitted from the ultrasonic sensor (140) is at its maximum in the cross section of the main body (102) and the bending direction (D2) of the tip portion (105), and the calculation processing unit (320) generates the image data indicating the bending direction (D2) of the tip portion (105) of the guide wire (100) based on the deviation angle data.

20. A blood vessel cross-sectional image display system (10, 10b) comprising: a connection part (200) to which a guide wire (100, 100b) having an ultrasonic sensor (140) is detachably attached; an arithmetic processing part (320) that generates image data by arithmetic processing of ultrasonic data acquired from the guide wire (100, 100b) inserted into a blood vessel via the connection part (200); and a display part (330) that displays a cross-sectional image of the blood vessel into which the guide wire (100, 100b) is inserted based on the image data, wherein in a cross section of the guide wire (100, 100b), the ultrasonic transmission / reception surface of the ultrasonic sensor (140) faces the outer periphery of the guide wire (100, 100b), The vascular cross-sectional image display system (10, 10b) generates the image data so that the position of the ultrasonic sensor (140) is shown in the center of the cross-sectional image, an image at the current time is shown in a specific region (R1) with a width that indicates depth information including the transmission direction of ultrasonic waves from the center, and an image at a past time is shown in a region (R2) other than the specific region.

21. A blood vessel cross-sectional image display system (10, 10b) according to claim 20, wherein the specific region (R1) is a substantially sector-shaped region that is line-symmetric with respect to the transmission direction of the ultrasound.

22. A blood vessel cross-sectional image display system (10, 10b) according to claim 21, wherein the arithmetic processing unit (320) variably sets the central angle of the specific region (R1).

23. A blood vessel cross-sectional image display system (10, 10b) comprising: a connection part (200) to which a guide wire (100, 100b) having an ultrasonic sensor (140) is detachably attached; an arithmetic processing part (320) that generates image data by arithmetic processing of ultrasonic data acquired from the guide wire (100, 100b) inserted into a blood vessel via the connection part (200); and a display part (330) that displays a cross-sectional image of the blood vessel into which the guide wire (100, 100b) is inserted based on the image data, wherein in a transverse cross section of the guide wire (100, 100b), an ultrasonic transmission / reception surface of the ultrasonic sensor (140) faces the outer periphery of the guide wire (100, 100b), and the arithmetic processing part (320) generates the image data so as to show a symbol indicating the radial position of the received ultrasonic data in the cross-sectional image, a blood vessel cross-sectional image display system (10, 10b) configured to generate the image data such that during a period from a start time (t0) of rotation of the base end of the guide wire (100, 100b) to a specific time (t1), the position of a symbol based on received ultrasound data remains unchanged, and during a period after the specific time (t1), the symbol is updated along a line rotated by an amount of rotation of the guide wire (100, 100b) from a start line indicating the transmission direction of ultrasound at the start time (t0).

24. A vascular cross-sectional image display system (10, 10b) according to claim 23, wherein the specific time (t1) is the time when rotation of the installation position of the ultrasonic sensor (140) on the guide wire (100, 100b) begins.

25. A blood vessel cross-sectional image display system (10, 10b) according to claim 23 or claim 24, wherein the calculation processing unit (320) generates the image data so that the symbol is displayed along the start line at the start time (t0) in the cross-sectional image.

26. A vascular cross-sectional image display system (10, 10b) according to any one of claims 23 to 25, wherein the symbol includes an image of a specific region (R1) with a certain width that indicates depth information including the direction of transmission of ultrasound from the center of the cross-sectional image.

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