Body cavity model tube and method for manufacturing body cavity model tube

Abstract

To provide a body cavity model tube which can be used in training and the like of a cardiac catheter treatment and the like using an optical interference tomographic image diagnosis device or the like as a guide.SOLUTION: There are provided, a manufacturing method of a body cavity model tube which is used in training and the like of treatment and / or diagnosis of a disease via a body cavity and in which smoothness of an inner wall surface is equal to or less than 1.5 μm such that irregularity existing on the inner wall surface has small occurrence of Mie scattering and the inside of the tube can be imaged by an optical interference tomographic image diagnosis device, and a body cavity model tube by means of a molding press method by using a core and a split die for manufacturing tube by manufacturing the core by injecting a core material to a core molding split die after eliminating a fitting gap of a core molding die by coating liquid whose viscosity is adjusted to 0.05-5 Pa s by adding a solvent compatible with the core material to a thermosetting type coating material incompatible with the core material to an inner surface of the core molding die.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a body cavity model tube and a method for manufacturing a body cavity model tube, and more particularly to a body cavity model tube that can be used for treatments such as cardiac catheter treatment and / or diagnostic training, and that can suppress deterioration of the image quality of the images obtained, and a method for manufacturing such a body cavity model tube that can produce such a body cavity model tube easily and in a short period of time. [Background technology]

[0002] In the treatment of ischemic heart disease such as myocardial infarction or angina caused by the progression of arteriosclerosis due to lifestyle or aging and the narrowing of the coronary artery, catheter treatments such as cardiac catheterization (PCI (Percutaneous Coronary Intervention) and PTCA (Percutaneous transluminal catheter angioplasty)) are performed. Catheterization is a treatment in which a catheter is inserted into a blood vessel in the wrist or thigh, and a balloon or stent is used to expand the heart or narrowed or clogged blood vessels to improve blood flow. In this catheterization, it is necessary to clarify the pathology of the disease in advance, so intravascular imaging (image diagnosis) is performed. Intravascular imaging can obtain high-resolution images inside the blood vessels and can grasp the characteristics of thrombus or arteriosclerosis, so it is used to diagnose the pathology or determine the treatment plan before catheterization, and is also used for evaluating stent placement after treatment.

[0003] Traditionally, intravascular imaging has been performed using ultrasound, known as intravascular ultrasound (IVUS), and in recent years, optical coherence tomography (OCT) has become more common. 、Inspections using optical frequency domain imaging (OFDI) have also come to be performed (see Patent Document 1). Furthermore, an IVUS-OCT hybrid device that combines the advantages of both IVUS and OCT has been proposed. Here, in IVUS, a catheter equipped with an ultrasonic sensor (ultrasonic probe with a built-in transmitting / receiving unit made of ultrasonic transducer) at the tip is inserted into a blood vessel such as a coronary artery, and passed to the lesion, and then, while rotating the transmitting / receiving unit, ultrasonic waves are emitted and transmitted from the ultrasonic sensor into the blood vessel, and reflected waves (ultrasonic echoes) from the living body such as the blood vessel wall are received to perform radial scanning, and a tomographic image of the blood vessel is depicted based on the intensity of the ultrasonic echo signal generated by amplifying, detecting, etc., the reflected waves obtained in this way, so that a tomographic image of the inside of the blood vessel can be viewed in real time. The tomographic image in IVUS is two-dimensional, has a resolution of about 100 μm, and a penetration depth of about 10 mm (see Patent Document 1).

[0004] However, as the focus of intracoronary imaging has shifted toward plaque characterization and endothelial coverage, the limitations of the relatively low resolution (100–150 μm) of IVUS have become apparent. In contrast, OCT, or OFDI, has emerged as an attractive new imaging modality due to its superior resolution (10–15 μm), clear images with good contrast, the ability to reconstruct 3D cross-sectional images, and the ability to characterize intravascular plaque and closely monitor stent placement. In such OCT or OFDI, a catheter equipped with a transmitting / receiving unit with an optical lens and an optical mirror attached at the tip and an optical probe unit with an optical fiber built in is inserted into a blood vessel, and while rotating the transmitting / receiving unit, radial scanning is performed by receiving the reflected light from the biological tissue, and a two-dimensional tomographic image of the blood vessel based on the interference light is obtained by interfering the reflected light obtained thereby with a reference light previously divided from the measuring light, and a three-dimensional reconstructed image is depicted based on the data obtained by continuously scanning while shifting the axial position in the blood vessel. That is, the cross section of the blood vessel is measured by the interference method, and a three-dimensional tomographic image is obtained. For this reason, the resolution of OCT or OFDI is about 10 to 15 μm as described above, which is about 10 times higher than that of IVUS, and the penetration depth is about 1 mm, making it excellent for evaluating calcification or thrombus, which are difficult to evaluate with IVUS.

[0005] One of the present applicants has already proposed a manufacturing method for tubular models such as blood vessel models used for training in catheter techniques to perform examination and treatment methods within blood vessels by inserting a catheter into the blood vessel for the purpose of examining and treating heart and blood vessel diseases with little burden on the body, and for evaluating the performance of catheters as treatment instruments, as well as a blood vessel model, a blood vessel model simulator, and a molding die (see Patent Document 2). It is said that this tubular model such as a blood vessel model can improve productivity, is suitable for mass production, and is economically advantageous. When using this tubular model such as a blood vessel model to perform minimally invasive treatment via a body cavity, such as cardiac catheterization (PCI or PTCA), and / or diagnostic training, by using IVUS as a guide for treatment or diagnosis, it is possible to reliably image the inner surface of the tubular model such as a blood vessel model, and obtain tomographic images of sufficient and appropriate image quality. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 5399844 [Patent Document 2] Patent No. 6120504 Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, blood vessels, and in particular lesions at the branching points of blood vessels, have become complex and diverse. In order to overcome the difficulties in treating each disease state and to improve treatment outcomes, doctors and medical device manufacturers have been actively researching and developing treatment methods and medical devices to be used in treatment. For the purpose of examining and evaluating these methods, there has been a strong demand for tubes that model blood vessels, and in particular branching tubes. However, when using a tubular model such as the blood vessel model disclosed in Patent Document 2 to perform training for treatments such as cardiac catheterization (PCI or PTCA) and / or diagnosis, if OCT or OFDI is used instead of IVUS as a guide for treatment or diagnosis, there is a problem that the inner surface of the tubular model such as the blood vessel model cannot be reliably imaged and the necessary three-dimensional tomographic images cannot be obtained, or even if imaging is possible, it is not possible to reliably image with an accuracy according to the performance of the OCT or OFDI, and three-dimensional tomographic images of sufficient accuracy and appropriate image quality cannot be obtained. In recent years, OCT or OFDI has been increasingly used as a guide for treatment and / or diagnosis, such as cardiac catheterization (PCI or PTCA), and there is a strong demand for solving the above problems.

[0008] An object of the present invention is to provide a body cavity model tube that can be used for training in minimally invasive treatment and / or diagnosis via a body cavity, such as cardiac catheterization using an optical coherence tomography imaging diagnostic device or the like as a guide, planning and / or research of treatment and / or diagnosis strategies, and development and / or evaluation of medical devices, such as optical coherence tomography imaging diagnostic devices, used for treatment and / or diagnosis, and that can suppress deterioration in the accuracy and image quality of tomographic images obtained by imaging the inner surface, and a method for manufacturing such a body cavity model tube that can be manufactured in a reduced manufacturing process and in a shortened time. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the body cavity model tube of the first aspect of the present invention is used for training in the treatment and / or diagnosis of diseases via body cavities, planning and / or research of treatment and / or diagnosis strategies, and development and / or evaluation of medical devices used for treatment and / or diagnosis, and is a flexible and elastic tube that models a body cavity, and is characterized in that the inner wall surface of the tube has unevenness present as a base undulation or inclination of the inner wall surface within a range of ±1.5 μm, the rate of change of the unevenness is 0.03 or less in horizontal and vertical cross sections, and the number of protrusions on the inner wall surface that are particulate unevenness and have a height of half the value of 2 / π or more of the wavelength of light used in an optical coherence tomography imaging diagnostic device is 20 or less per 335 μm x 335 μm. Therefore, the unevenness on the inner wall surface of the body cavity model tube of the first embodiment of the present invention is small and changes gradually, and the particulate unevenness is extremely small, resulting in little Mie scattering, making it possible to image the inside of the body cavity model tube by imaging with an optical coherence tomography imaging diagnostic device.

[0010] Here, the tube is preferably a branched tube having a branched shape including a trunk portion and at least one branch portion branched off from the trunk portion. In addition, it is preferable that the branching shapes include Y-shapes, T-shapes, L-shapes, and repetitions and / or combinations of these shapes, as well as biologically derived branching shapes that can be obtained based on angiography data when the body cavity is a blood vessel. The tube is manufactured by using a core to form the hollow portion of the tube and transferring the outer surface of the core to the inner wall surface of the tube by a molding press method, and it is preferable that the outer surface of the core is smoothed to a smoothness of 390 nm or less, at which point Mie scattering does not occur in spherical particles. In addition, it is preferable that the tube is a blood vessel model in which the body cavity is a blood vessel and imaging by an optical coherence tomography imaging apparatus is possible.

[0011] In order to achieve the above object, a method for producing a body cavity model tube according to a second aspect of the present invention is the method for producing a body cavity model tube according to the first aspect, The core material is injected into the core forming mold to produce the hollow part of the tube. A liquid made by adding a thermosetting coating material that is incompatible with the core material to a solvent that is compatible with the coating material and adjusting the viscosity to 0.05 to 5 Pa s is sprayed onto the inner surface of the core forming mold to eliminate any gaps between the core forming mold and the fitting. The core material is then injected into the core forming mold to produce the core. The produced core and a tube production mold are used to manufacture tubes by a molding press method. Here, the smoothness of the outer surface of the core is preferably set to 390 nm or less, at which point any irregularities present on the outer surface will not cause Mie scattering in spherical particles and imaging of the inside of the tube will be possible using an optical coherence tomography imaging device.

[0012] Also, a liquid having an adjusted viscosity is sprayed onto a hollow surface of each of the two or more molds constituting the core molding split mold into which the core material is injected, to form a paint coating; Two or more molds are fitted together and the coating material that has been painted on the inner surface is bonded to each other to produce a core forming split mold in which there is no gap between the two or more core forming dies, The core mold is placed in an electric furnace to harden the coating material, and then The core material is poured into the core mold and allowed to harden. The core, the surface of which is coated with the coating material, is removed from the core molding split mold. It is preferable to produce the core by peeling off the coated coating material. In addition, after the coating material applied to the inner surface of the core molding split mold is hardened, The core mold is set in the vacuum casting machine, and after vacuuming, It is preferable that the core material is poured into a core molding die, degassed, and then placed in an electric furnace. The core material is thermally hardened, then removed from the electric furnace, cooled, and then the core molding die is released to remove the core.

[0013] In addition, the compatibility between the coating material and the core material, and the compatibility between the coating material and the solvent are preferably evaluated by the Hansen solubility parameters. In addition, the term "incompatibility between a coating material and a core material" preferably means that the center of each of their Hansen Solubility Parameters (HSP) is outside the sphere of the interaction radius of the other in the Hansen space, and the term "compatibility between a coating material and a solvent" preferably means that the center of each of their Hansen Solubility Parameters (HSP) is inside the sphere of the interaction radius of the other in the Hansen space. Effect of the Invention

[0014] According to the present invention, even when an optical coherence tomography imaging diagnostic device or the like is used as a guide, a body cavity model tube can be provided that can be used for training in minimally invasive treatment and / or diagnosis via a body cavity, such as cardiac catheterization, planning and / or research of treatment and / or diagnosis strategies, and development and / or evaluation of medical devices, such as optical coherence tomography imaging diagnostic devices, used for treatment and / or diagnosis, and that can suppress deterioration in the accuracy and image quality of images obtained by imaging the inner surface. Furthermore, according to the present invention, it is possible to provide a method for producing such a body cavity model tube, which can produce such a body cavity model tube with reduced production steps and in a shortened time. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view showing a body cavity model tube according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of the body cavity model tube shown in FIG. [Diagram 3] 13(a) and (b) are perspective views that typically show a body cavity model tube according to another embodiment of the present invention. FIG. [Figure 4] 13(a) and (b) are perspective views that typically show a body cavity model tube according to another embodiment of the present invention. FIG. [Diagram 5] 2(a) to 2(d) are graphs showing the surface properties of the inner wall surface of the body cavity model tube shown in FIG. [Figure 6] 2(a) and 2(b) are graphs showing the surface properties of other inner wall surfaces of the body cavity model tube shown in FIG. [Figure 7] 1 is a flowchart showing an overview of a method for producing a body cavity model tube according to one embodiment of the present invention. [Figure 8] 8(a) to 8(d) are conceptual diagrams showing an example of a core used in the method for producing the body cavity model tube shown in FIG. 7 and a production process thereof. [Figure 9] 8(a) to 8(d) are graphs showing the surface properties of the outer surface of the core shown in FIG. 8(a). [Figure 10] 8(a) to 8(c) are conceptual diagrams showing an example of a manufacturing process for the body cavity model tube shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The body cavity model tube of the present invention and the method for producing this body cavity model tube will be described below. First, a body cavity model tube according to an embodiment of the present invention will be described in detail with reference to a preferred embodiment shown in the accompanying drawings. The body cavity model tube of this embodiment is used for training in minimally invasive treatment and / or diagnosis via body cavities such as blood vessels, such as cardiac catheterization, planning and / or research of treatment and / or diagnosis strategies, and development and / or evaluation of medical devices such as optical coherence tomography imaging (OCT or OFDI) used for treatment and / or diagnosis.

[0017] Fig. 1 is a perspective view showing a body cavity model tube according to a first embodiment of the present invention, Fig. 2 is a schematic longitudinal sectional view of the body cavity model tube shown in Fig. 1. In this application, the drawings are for explaining the present invention, and each drawing and each component is enlarged or emphasized in order to suitably explain each component, and the dimensions are different from the actual dimensions. In addition, the embodiment shown in the drawings is merely an example of the present invention, and the present invention is not limited to the embodiment described in these drawings. The body cavity model tube of the present invention is a model of an actual body cavity of a living organism. In the following, blood vessels such as coronary arteries are used as a representative example of a body cavity, and a blood vessel model tube is used as a representative example of a body cavity model tube; however, the present invention is not limited to this, and it goes without saying that other arteries, blood vessels such as veins, lymphatic vessels, urinary organs (ureters, bladder, urethra, etc.), reproductive organs (prostate, seminal vesicles, penis, testes, etc.), bile ducts, digestive tracts (esophagus, small intestine, large intestine, etc.), etc. may also be used as body cavities that are the subject of the present invention.

[0018] The blood vessel model tube (hereinafter, simply referred to as a tube) 10 of this embodiment shown in Fig. 1 is a branched tube having a branched shape including a trunk portion 12 and two branch portions 14, 14 branched from the trunk portion 12. A hollow portion 12a is formed inside the trunk portion 12, and hollow portions 14a, 14a are formed inside the two branch portions 14, 14, respectively. The hollow portion 12a and the two branches 14a, 14a are smoothly and continuously connected to each other, constituting the hollow portion 10a of the tube 10. As shown in Figure 2, which is a longitudinal cross-sectional view of tube 10 along hollow portion 10a, hollow portion 12a is formed by inner wall surface 12b of trunk portion 12, and hollow portions 14a, 14a are formed by inner wall surfaces 14b of branch portions 14, 14, respectively, and inner wall surface 12b and inner wall surfaces 14b, 14b are smoothly continuous with each other and form inner wall surface 10b of tube 10. Therefore, the tube 10 has a tubular, for example, cylindrical, shape, and the hollow portion 10a surrounded by the inner wall surface 10b is a portion that forms a blood vessel flow path through which blood flows. In the following description, even if there are two or more branch-like portions 14, hollow portions 14a, and inner wall surfaces 14b, they may be simply referred to as branch-like portions 14, hollow portions 14a, and inner wall surfaces 14b.

[0019] The tube 10 is made of silicone resin, specifically, a simulated blood vessel that models a blood vessel made of silicone rubber. The tube 10 is made of silicone rubber, which is transparent or semi-transparent with a transmittance of 34% or more, and has flexibility and elasticity similar to that of blood vessels in an actual living body. As a result, the tube 10 is often required to have high flexibility and elasticity, but some users may wish to simulate different disease states, and the hardness of the tube 10 is set to 5 to 60 in type A according to the Japanese Industrial Standards (JIS K 6235). That is, the tube 10, which is a blood vessel model, is required to have softness, radial elongation (circumferential elongation), as well as a certain tear strength (tensile strength) and a certain transparency, just like a blood vessel. The transmittance can be measured by cutting the tube 10 and measuring the cut portion with a spectrophotometer, such as SD7000 by Nippon Denshoku Industries Co., Ltd. It is preferable to use silicone rubber as the material for the tube 10. However, any other material that is transparent, flexible, elastic, and hard may be used. To Non-limiting examples include polyvinyl alcohol (PVA), and when transparency is not required, urethane rubber can also be used.

[0020] In particular, the following three requirements are required for tubes for PCI / PTCA simulation and branch tubes. (1) Realism: The material must have a soft and elastic texture, be smooth enough not to impair the traversability of the guidewire, have no unevenness, have material properties and shape precision that can withstand the expansion of the stent, and have the anatomical characteristics specific to the bifurcation. (2) Visibility: The stent or catheter inside the tube must have good visible light transmittance so that it can be seen with the naked eye from the outside. (3) In order to perform a simulation while displaying an external camera image on a monitor, strong light is required, and the surface must have optical properties that prevent halation caused by that light. Furthermore, for a tube to be used in OCT / OFDI-guided PCI / PTCA simulation, there is also a requirement that the positional relationship between the inner wall of the tube and the stent can be imaged by OCT / OFDI. Therefore, if the tube is made of silicone, we use KE-1608 from Shin-Etsu Chemical Co., Ltd. or Silopren LSR2020 from Momentive Co., Ltd.; rubber hardness (Shore A, ISO 48-4:2018) 22, tear elongation rate 1000% (ISO37 Type1), tear strength 15N / m, tensile strength 6.5N / m 2 By using the above, it is possible to satisfy the physical properties described in (1) and the light transmittance described in (3). Other products include Momentive's Silopren LSR2010, 2020, 2030, 2040, 2050, 2060, Silopren LSR4020, 4030, 4040, 4050, 4060, Wacker's Elastsil LR3003 / 05, LR3003 / 10 TR, LR3003 / 20 TR, LR3003 / 25, LR3003 / 30, LR3003 / 40, LR3003 / 50, LR3003 / 60, and Dow Corning's SILASTIC RBL-9200-20 LSR, RBL-9200-30 LSR, RBL-9200-40 LSR, RBL-9200-50 LSR, RBL-9200-60. LSR, can also be used.

[0021] Furthermore, in the blood vessel model tube 10, the inner diameter of the hollow portion 14a is often equal to or smaller than the inner diameter of the hollow portion 12a, and the inner diameter of the hollow portion 10a is not constant and is not particularly restrictive. The inner diameter of the hollow portion 10a (12a, 14a) is not particularly restrictive, but is preferably formed within a range of φ0.1 mm to φ2.0 mm when targeting veins, capillaries, peripheral blood vessels, or the like. This is because if the inner diameter of the hollow portion 10a is less than φ0.1 mm, it becomes difficult to insert a catheter. The tube 10 having such a configuration has a minute inner diameter dimension of the hollow portion 10a, and is also suitable as a blood vessel model for peripheral blood vessels. Meanwhile, in the case of aorta, the inner diameter of hollow portion 10a may be φ30 mm to φ40 mm, and in the case of blood vessels, it may of course be φ2.0 mm or more. Furthermore, the thickness of the blood vessel model tube 10 is not particularly limited, but is preferably 0.05 mm to 2 mm. In the case of a body cavity model tube that models a body cavity other than a blood vessel, the size, inner diameter, etc., of the tube may be formed to match the size, inner diameter, etc. of a body cavity of an actual living body.

[0022] The tube 10 shown in FIG. 1 is a branched tube whose branch shape is a T-shape, but the branch shape of the branched tube is not limited to this and may be a Y-shape like the tube 10A shown in FIG. 3(a), a T-shape like the tube 10B shown in FIG. 3(b), or a repetition and / or combination of these branch shapes, as described below. In addition, the branched tubes 10, 10A, and 10B each have one branch portion 14 for one trunk portion 12, but the present invention is not limited to this, and it is sufficient for one trunk portion 12 to have two or more branch portions 14, as described below.

[0023] Furthermore, the trunk portions 12 and branch portions 14 of the tubes 10, 10A, and 10B shown in Figures 1, 3(a), and 3(b), respectively, are all straight pipes without any bends, but the present invention is not limited to this, and both the trunk portions 12 and the branch portions 14 may be curved, as in the tubes 10C and 10D shown in Figures 4(a) and 4(b). Also, like tubes 10C and 10D shown in Fig. 4(a) and Fig. 4(b), each may have two or more branch portions 14A that are formed by further branching a branch portion 14 branched from a trunk portion 12. Furthermore, like tube 10D shown in Fig. 4(b), three or more branch portions 14 may be formed branched from the trunk portion 12, and two or more branch portions 14A may be formed by each of the branch portions 14. The branch portions 14A may be further branched, or may be further branched repeatedly. Furthermore, for example, in the case where the body cavity is a tube made up of blood vessels, although not shown, the branching shape of blood vessels originating from a living body that can be obtained based on angiography data may be included.

[0024] The inner wall surface 10b of the tube 10 shown in Fig. 2 must have a smoothness such that the particulate unevenness of the inner wall surface 10b is 390 nm or less at which Mie scattering does not occur when 1310 nm light is applied to spherical particles, and other unevenness such as base undulations and base inclinations present on the inner wall surface 10b are within a range of ±2.0 μm, preferably ±1.5 μm, and the rate of change of other unevenness is 0.040, preferably 0.030 or less in the horizontal cross section and the vertical cross section. That is, the particulate unevenness present on the inner wall surface 10b of the tube 10 is less than the size at which Mie scattering does not occur when 1310 nm light is applied to spherical particles, and the other unevenness is small and changes gradually, so that imaging of the inside of the tube is possible by imaging with an optical coherence tomography (OCT or OFDI) or the like. As described in the prior art, the conventional vascular model is not used as a guide for treatment, etc. OCT When using OFDI, there was a problem that the inner surface of a tubular model such as a blood vessel model could not be reliably imaged, or that a 3D tomographic image with sufficient accuracy and appropriate image quality could not be obtained. For this reason, the inventors suspected that diffuse reflection and scattering were due to the surface properties of the inner wall surface of the vascular model tube, and hypothesized that by referring to the particle diameter at which Mie scattering occurs in spherical particles and removing irregularities larger than that size, it may be possible to reduce the attenuation of signals for OCT / OFDI imaging due to diffuse reflection and scattering.Based on this hypothesis, they calculated the particle diameter at which Mie scattering occurs, based on the near-infrared wavelengths used in OCT / OFDI.

[0025] As a wavelength swept light source used in OCT / OFDI such as SS-OCT (swept-source OCT), we referred to the specifications of Santec's high-precision light source model HSL-2100, which sweeps the wavelength in the range of ±85 nm centered on 1310 nm. The resolution calculated from this wavelength sweep width is 4.4 μm, which is higher than the current resolution of OCT / OFDI, which is said to be 10-20 μm. Using this specification as a next-generation light source that is expected to be adopted in the future, we calculated the particle size at which Mie scattering occurs with light of the shorter wavelength of 1225 nm. α=πd / λ where d is the particle size and λ is the wavelength of the incident light. Mie scattering occurs when α = 2. At that time, the particle diameter d is d = 2λ / π. d=2×1225 / π=780nm From the above, since the particle size (diameter) d is 780 nm, the length equivalent to half the radius: 390 nm was used as a guideline, and the irregularities on the inner wall surface of the blood vessel model tube were adjusted to be less than 390 nm. Taking these results into consideration, the hypothesis was formulated that if irregularities greater than approximately 390 nm could be reduced from the inner wall surface 10b (12b, 14b) of the tube 10, imaging of the inner wall surface 10b (12b, 14b) of the tube 10 would be possible. The fact that Mie scattering occurs when α = 2 is based on the information in "Fundamental Properties of Powders" published by the Nikkan Kogyo Shimbun and edited by the Society of Powder Technology, which states that Mie scattering occurs when the particle size parameter is greater than 2 and less than 10.

[0026] To check the condition of the inner wall of the tube and the surface of the core, non-contact optical profile measurement using coherence correlation interferometry may be performed. A non-contact 3D roughness measurement device such as CCI HD XL from Taylor Hobson, a division of AMTEK, can be used. To confirm whether the particle irregularities can be confirmed even with an optical microscope, refer to the following available particles with a particle size of 400 nm. ·Ocean nano tech (Ca, San Diego) F61504 Micromod Sicastar 43-00-402 Glantreo PNPP0.40NAR-5 The resolution limit δ of the optical microscope was calculated. δ=kλ / NA Here, NA (numerical aperture) = nsinθ, n = 1 in air, θ is 72° maximum, so NAmax = 0.95 is used as NA, k is the Rayleigh limit of 0.61, and λ is the green wavelength at which the eye is most sensitive: 550 nm. δ=0.61×550 / 0.95=353nm From the above, it can be said that the limit of irregularities on the inner wall surface 10b (12b, 14b) of the tube 10, 390 nm, is larger than the resolution limit δ (=353 nm) of the optical microscope described above and is therefore observable.

[0027] After confirming the above points, the inventors hypothesized that since the inner wall surface 10b (12b, 14b) of the tube 10 is a transferred surface of the outer surface 20a of the core 20 (see Figure 8(a)) as described later in the manufacturing method of the body cavity model tube of the present invention, the surface properties of the inner wall surface 10b depend on the surface properties of the outer surface 20a of the core 20, and that when the surface of the inner wall surface 10b contains particulate irregularities, the smoothness (surface irregularities) of the inner wall surface 10b of the tube 10 is close to the smoothness (surface irregularities) of the outer surface 20a of the core 20.

[0028] On the other hand, the molding die used to manufacture the core (corresponding to the core of the present invention) for manufacturing a tubular model such as a blood vessel model manufactured by the method described in Patent Document 2 is one-piece and has a structure in which the removal part consisting of a planar cut on the branch-like part side is opened, so that a parting line remains on the branch-like part of the core. Not limited to this example, even when the core is manufactured using a split molding die, this parting line inevitably remains on the core. For this reason, even if the parting lines remaining on the core material and the core are scraped off with a sander or the like and the outer surfaces are polished, fine particulate irregularities due to scratches caused by polishing remain on the outer surface. For this reason, it is estimated that the inner wall surface of a tubular model or the like manufactured using such a core material and core has fine particulate irregularities exceeding 390 nm, and as described above, there is a problem in that imaging of the inside of the tubular model or the like by OCT / OFDI is not possible.

[0029] For this reason, since the core 20 has a parting line resulting from its manufacturing method (which is unavoidable since a split mold is used), the inventors sanded and polished the parting line to make its outer surface 20a smooth, and then performed a correction process using putty to hide scratches caused by polishing and to smooth out any unevenness that could not be removed, adjusting the surface to a mirror-like surface when visually confirmed. Furthermore, after repairing the outer surface 20a with putty, it was clear-painted to give it a solid mirror finish. The process of finishing the outer surface 20a of the core 20 to a mirror finish is labor-intensive, time-consuming, and time-consuming; however, as described above, the inventors have finished the outer surface 20a of the core 20 to a smooth mirror surface and reduced the unevenness of the outer surface 20a of the core 20 so that the particulate unevenness of the outer surface 20a of the core 20 is 400 nm or less. Since it is generally said that a mirror surface can be obtained by reducing particulate irregularities to 1 / 10 of the wavelength of light or less, the inventors attempted to reduce the irregularities to about 55 nm, which is 1 / 10 of the green wavelength of 550 nm, to which the eye is most sensitive, and polished the surface while checking the irregularities by touch and checking for mirror recognition with the naked eye. When the surface of core 20, which had been checked and polished, was observed with a scanning electron microscope at 20,000 to 50,000 times magnification, only slight irregularities of about 100 nm in size were confirmed on the surface.

[0030] The present inventors have used a core 20 having a smooth outer surface 20a and a smoothness (grain-like irregularities on the surface) of 390 nm or less to perform OCT / OFDI Therefore, imaging was performed and it was confirmed that imaging was possible. Therefore, the inventors cut the tube 10, which could be imaged by OCT / OFDI imaging, in half as shown in Figure 2, and performed non-contact optical profile measurement of the unevenness of the inner wall surface 10b using coherence correlation interferometry. AMETEK A Taylor Hobson CCI HD XL was used. Using a 50x eyepiece, measurements were taken at five locations over a measurement area of ​​335μm x 335μm, which was the scan range in this case. The cross-sectional profile of the measurement results was checked for unevenness in both the horizontal and vertical directions from one end of the measurement area to the other. The tube 10 used for the measurement was a Y-shaped tube as shown in FIG. 3(a), made of silicone resin with an outer diameter of 5 mm and an inner diameter of 3 mm.

[0031] Figures 5(a)-(b) show two characteristic horizontal cross-sectional profiles obtained by measuring five locations on the tube 10 using non-contact optical profile measurement using the above-mentioned coherence correlation interferometry, Figures 5(c)-(d) show two vertical cross-sectional profiles obtained by measuring another five locations, and Figures 6(a)-(b) show two vertical cross-sectional profiles obtained by measuring yet another location. The profiles at measurement locations not shown are similar to the profiles shown. The vertical axis of these figures is the height of the irregularities (μm), the horizontal axis of Figures 5(a)-(b) is the horizontal length (mm), and Figures 5(c)-(d) show two vertical cross-sectional profiles obtained by measuring yet another location. , and Figs. 6(a)-(b) The horizontal axis is the vertical length (mm). As is clear from these figures, the inner wall surface 10b of the tube 10 is generally smooth, and the number of irregularities of a size equivalent to the particle diameter (780 nm to 3900 nm) at which Mie scattering occurs for light of 1310 nm in a spherical particle is zero in Figs. 5(a) to (d) and one in Figs. 6(a) and (b), so even when other locations are taken into consideration, the number is 0 to 3. Other large irregularities (such as the waviness of the base of the inner wall surface 10b and the inclination of the base) are within the range of ±2.0 μm, preferably ±1.5 μm. The period of the other irregularities is at least 50 μm, so the rate of change is, in the horizontal cross section and the vertical cross section, 0.040 It was found that the smoothness should be less than (2.0 / 50=0.04), preferably less than 0.030 (=1.5 μm / 50 μm). From the above, in the case of particulate irregularities present on the inner wall surface 10a of the tube 10 of the present invention, the particulate irregularities present on the inner wall surface 10a are 390 nm or less, which is half the particle diameter at which Mie scattering occurs for light of 1310 nm in a spherical particle, and other irregularities present on the inner wall surface 10a are within the range of ±2.0 μm, preferably ±1.5 μm, and the rate of change of the other irregularities is 0.040 or less, preferably 0.050 or less, in the horizontal cross section and the vertical cross section. 0.030 It can be seen that the following is necessary:

[0032] The inventors have found that, as a way of thinking to enable imaging, random reflections due to fine irregularities on the surface of an object are repeated, and that it is necessary to suppress "diffuse reflection" in which light moves outward. Note that Mie-like scattering may occur even with surface irregularities, and there may be scattering from the side to the back, but as the particle diameter increases, forward scattering becomes dominant, and the proportion of scattering to the side and back decreases, but the scattering intensity increases by one to two orders of magnitude, so it was speculated that there may be a corresponding amount of scattering to the side and back. In addition, the inventors have hypothesized that when the particle density is high, multiple scattering cannot be ignored, and something related to Mie scattering occurs, which may contribute to OCT signal degradation, so they focused on the size of the particles that cause Mie scattering and tried to reduce the density of irregularities having that size. Aiming to achieve a smooth state in which irregularities larger than that size are reduced as much as possible, they tried to suppress the density of such protrusions to a certain number or less, and imaging became possible.

[0033] Based on this finding, the inventors further performed non-contact optical profile measurement of the inner wall surface 10a of the tube 10 using a non-contact three-dimensional roughness measuring device, employing coherence correlation interferometry. As a result, the inventors have discovered that, as described above, when the protrusions having a value of half 2 / π of the wavelength of light used in the optical coherence tomography imaging diagnostic device are particulate irregularities present on the inner wall surface 10a of the tube 10, imaging is possible if there are 20 or fewer protrusions per measurement area of ​​335 μm x 335 μm on the inner wall surface 10a. That is, the inventors considered that half of 2λ / π corresponds to the radius of a spherical particle where Mie scattering occurs, and that half of the spherical particle is protruding from the surface, and attempted to limit the number of such protrusions. In fact, they performed non-contact three-dimensional roughness measurement of five separate areas of 335 μm × 335 μm on the inner wall surface 10a of the tube 10, and confirmed the end-to-end of each area with the cross-sectional profile of the inner wall surface 10a, and concluded that imaging is possible if the number of protrusions having a height of half the value of 2 / π is 20 or less.

[0034] In view of the above, it is preferable that the tube 10 is manufactured by using a core 20 for forming the hollow portion 10a of the tube 10, the core 20 having an outer surface 20a with a smoothness of 390 nm or less, which reduces unevenness on the outer surface 20a and makes it possible to image the inside of the tube by imaging with an optical coherence tomography imaging diagnostic device, and by using a molding press method to transfer the smoothness of the outer surface 20a of the core 20 to the inner wall surface 10b of the tube 10. Moreover, it is preferable that the tube 10 is a blood vessel model in which the body cavity is a blood vessel and imaging by OCT / OFDI (optical coherence tomography imaging) is possible.

[0035] However, bifurcation lesions such as coronary artery bifurcation lesions are complex and diverse, and stent placement in such complex lesions such as bifurcations is difficult, and treatment outcomes are insufficient compared to non-bifurcation lesions. Therefore, overcoming the treatment difficulties and improving treatment outcomes are required according to each pathology. For this reason, doctors and manufacturers are actively researching and developing methods and devices. For this reason, there is a demand for a bifurcation tube model that faithfully reproduces the three-dimensional structure of the vascular lumen of humans, etc., and has no steps between the trunk and branches, in the development and evaluation of high-performance catheter devices such as balloon catheters and stents, as well as in the planning of treatment technology strategies and stent placement technology training. For this reason, the inventors have described the branched tubes 10-10D shown in Figures 1-4(b) as representative examples of the body cavity model tube of the present invention, but the present invention is not limited to branched tubes, and may be a single tube that is not branched, and this single tube may be a straight tube or a curved tube. Note that these single tubes that are not branched may be tubes consisting of only the trunk branch portion 12, or may be individual branch portions 14 and 14A, and are not shown in the figures. The body cavity model tube of the present invention is constructed as described above.

[0036] Next, a method for producing a body cavity model tube according to one embodiment of the present invention will be described in detail with reference to a preferred embodiment shown in the accompanying drawings. The method for producing a body cavity model tube of this embodiment is carried out in order to produce a body cavity model tube according to one embodiment of the present invention. Fig. 7 is a flow chart showing an outline of a method for manufacturing a body cavity model tube according to a second embodiment of the present invention. Figs. 8(a) to (d) are conceptual diagrams showing an example of a core used in the method for manufacturing the body cavity model tube shown in Fig. 7 and its manufacturing process. Figs. 10(a) to (c) are conceptual diagrams showing an example of a manufacturing process for the body cavity model tube shown in Fig. 7.

[0037] First, with reference to FIG. 7 and FIGS. 8(a) to (d), a core used in the method for producing a body cavity model tube of the present invention and its production process will be described. FIG. 8(a) is a perspective view showing a core, and FIG. 8(b) is a schematic view showing the inner surfaces of two molds of a core forming split mold for producing the core shown in FIG. plane 8(c) is a perspective view showing a core forming split mold in which the two molding dies shown in FIG. 8(b) are fitted together, and FIG. 8(d) is a perspective view showing a manufacturing state of a core using the core forming split mold shown in FIG. 8(c). In order to manufacture the tube 10 of the present invention, the manual process of mirror-finishing the outer surface 20a of the core 20 includes surface grinding to remove the parting line, polishing the outer surface, applying a surfacer, observing under an optical microscope, repairing, and clear coating, and has the problem of being labor-intensive, time-consuming, and troublesome, as described above. For this reason, the present inventors have invented a method for manufacturing a core that does not produce a parting line on the outer surface.

[0038] First, as shown in FIG. 7, in step S10, a core forming split mold 30 (see FIG. 8(b)) for producing the core 20 shown in FIG. 8(a) is prepared. Here, the core 20 is made of synthetic resin, and is made of epoxy resin. The reason is that when making the tube 10 with silicone resin, the epoxy resin is selected after confirming using the Hansen solubility parameters that the epoxy resin is a material that is not compatible with the silicone resin. To confirm this, the Hansen solubility parameter software HSPiP 5 th edition version 5.1.07 was used. The software comes with a database of polymers and solvents. With silicone as the target, the parameters between other polymers and the correlation of the radius of the sphere can be scored and rearranged based on the degree of overlap with the sphere of each polymer. When rearranging the relationships between silicone and other polymers in descending order of scoring, and selecting a polymer that is incompatible with silicone, the polymer with the lowest score can be used as a candidate substance, and a substance that satisfies other necessary conditions can be selected from among them. In the present invention, when manufacturing the tube 10, the silicone resin is heated to a high temperature of 80 to 150°C (depending on the material) to harden it, which is a high temperature for resin. However, epoxy exists as a resin that has a melting point higher than the heating temperature for hardening this silicone, and the core does not melt when the silicone is heated and hardened, so that epoxy resin is selected as a material that can withstand high temperatures. However, synthetic resins other than epoxy resins may be selected and used as long as they satisfy the above conditions. As shown in Fig. 8(a), such a core 20 is for forming the hollow portion 10a of the tube 10 shown in Fig. 1, and has a shape obtained by inverting the hollow portion 10a of the tube 10, and similarly corresponds to the tube 10 and includes a trunk portion 22 and two branch portions 24, 24 branching off from the trunk portion 22. A gripping portion 26 is formed extending from the trunk portion 22 to the opposite side to the branch portion 24. In addition, gripping portions 27 and 28 are formed extending from the branch portion 24 to the opposite side to the trunk portion 22.

[0039] The core molding split mold 30 is a split mold made of silicone, and is constructed by fitting two silicone molding dies 32 and 34 together, as shown in Figs. 8(b) and (c). Here, the two molding dies 32 and 34 may be an upper molding die and a lower molding die that are fitted together vertically. Recesses 32b and 34b are formed on the inner surfaces 32a and 34a of the two molding dies 32 and 34, respectively, along the outer peripheral shape of half of the core 20. The recesses 32b and 34b have portions corresponding to the trunk portion 22 and the two branch portions 24 and 24, respectively. In the core forming split mold 30, which is combined by fitting the inner surfaces 32a and 34a of the two molding dies 32 and 34 together, the recesses 32b and 34b combine to form a material injection cavity 36 that follows the outer circumferential shape of the core 20. Specifically, a continuous material injection cavity 36 is formed that corresponds to the trunk portion 22 and branch portions 24, 24 of the core 20 and further corresponds to the gripping margin 26. Note that core material for producing the core 20 is injected into the material injection cavity 36.

[0040] If the core-forming split mold 30 is not prepared, the core-forming split mold 30 may be prepared as follows. First, a resin core mold model is made of photocurable resin, for example, epoxy resin, using a stereolithography method. This resin core mold model is a prototype model for producing the core molding split mold 30, and naturally, a cavity is formed along the outer wall of the core 20. By creating an inverted mold from this resin core mold model using heat-resistant silicone resin or the like, it is possible to produce a silicone core molding split mold 30.

[0041] Next, in step S12 shown in FIG. 7, the recesses 32b, 34b of the inner surfaces 32a, 34a of the two molding dies 32, 34 are painted with a liquid whose viscosity is adjusted by adding a solvent to a thermosetting coating material. Here, it is preferable that the coating material is a material that is not compatible with the core material, and that the solvent used to adjust the viscosity of the coating material is compatible with the coating material and volatilizes during heating and curing after the coating material is applied to the mold. Note that in the present invention, the compatibility between the coating material and the core material, and the compatibility between the coating material and the solvent are preferably evaluated by the Hansen solubility parameter. In addition, the absence of compatibility between the coating material and the core material preferably means that in the Hansen space, the center of each of the Hansen Solubility Parameters (HSP) is outside the sphere of the interaction radius of the other. When a coating material and a solvent are compatible with each other, the center of the Hansen solubility parameters (HSP) of each of them is preferably inside a sphere of the interaction radius of the other in the Hansen space.

[0042] Here, the Hansen solubility parameter (HSP) is based on the idea that "two substances with similar intermolecular interactions are easily dissolved in each other", and is calculated by three parameters (unit: MPa): the energy D due to intermolecular dispersion forces, the energy P due to intermolecular dipole interactions, and the energy H due to intermolecular hydrogen bonds. 0.5 ) These three parameters are the coordinates of the Hansen (three-dimensional) space, and when the HSPs of two materials 1 and 2 are placed in the Hansen space, the compatibility of the two materials 1 and 2 can be expressed by the distance L between the two points. The distance L between the two points can be expressed by the following formula (1). L 2 =(D2-D1) 2 +(P2-P1) 2 +(H2-H1) 2 ………(1) The compatibility of two materials 1 and 2 can be determined from the interaction radius R of material 1 and the distance L between the two points. When L>R, the HSP of material 2 is inside a sphere of radius R of material 1, which indicates that there is no compatibility between materials 1 and 2. On the one hand, when L < R, the HSP of Material 2 is outside the sphere with radius R of Material 1, indicating that there is compatibility between Material 1 and Material 2.

[0043] From the above, for the coating material spray-coated on the inner surfaces 32a and 34a including the recesses 32b and 34b of the neutron forming mold 30, a material incompatible with the neutron 20 is selected. When an epoxy resin is used as the neutron material, the software HSPiP 5 th edition version 5.1.07 is used to target epoxy, and the correlation between the parameters and the sphere radius with other polymers can be scored based on the overlapping degree of the spheres of each polymer and sorted. Among the multiple other polymers scored and sorted in relation to epoxy, a convenient one can be selected from the substances / materials with low scores, and silicone can be selected as one such coating material. When the viscosity of silicone is high, a solvent compatible with silicone is selected according to the Hansen solubility parameter to adjust the viscosity. Here too, HSPiP 5 th edition version 5.1.07 is used to sort and display the solvents compatible with silicone (also denoted as PDMS) in ascending order of small RED, and a compound rich in compatibility and meeting the conditions can be selected. In this case, toluene can be cited as one of the selectable solvents. Which solvent to adopt can be selected according to cost, environmental measures, safety, etc., considering their production and circumstances. Silicone and the solvent are made into a liquid in a uniform mixed state without bubbles by self-rotation stirring in a vacuum, and the viscosity of the liquid is adjusted by the amount of the added solvent.

[0044] In the present invention, the viscosity of the liquid obtained by adding a solvent to a thermosetting coating material needs to be adjusted to 0.05 to 5 Pa·s. If the viscosity of the liquid is less than 0.05 Pa·s, the liquid flows and accumulates at the bottom of each of the recesses 32b and 34b of the two molding dies 32 and 34, and the surfaces of the recesses 32b and 34b cannot be uniformly coated. If the viscosity of the liquid is more than 5 Pa·s, the liquid adheres unevenly to the surfaces of each of the recesses 32b and 34b of the two molding dies 32 and 34, and the surfaces of the recesses 32b and 34b cannot be uniformly coated. The viscosity-adjusted mixture of silicone and solvent is sprayed by an air gun onto the inner surfaces of the two molding dies 32 and 34 of the core molding split die 30 to coat them.

[0045] Next, in step S14 shown in FIG. 7, the two molding dies 32 and 34 are fitted and fixed with their respective inner surfaces 32a and 34a facing each other, as shown in FIG. 8(c), and the coating materials applied to the inner surfaces 32a and 34a including the recesses 32b, 34b are connected to each other, thereby producing the core forming split die 30 in a state where there are no fitting gaps that could cause parting lines. Next, in step S16, the core-forming split mold 30 in the fitted state is placed in an electric furnace to thermally cure the applied coating material. At this point, the solvent has evaporated, and a thin film of silicone resin with a hollow inner surface with no fitting gap for producing the core 20 is formed and adhered to the surfaces of the recesses 32b and 34b of the fitted core-forming split mold 30. The core-forming split mold 30 is then removed from the electric furnace.

[0046] Next, in step S18 shown in FIG. 7, the core molding split mold 30 removed from the electric furnace is set in a vacuum casting machine, and after evacuation, epoxy resin of the core material is injected into the core molding split mold 30. Next, in step S20 shown in FIG. 7, the core forming split mold 30 into which the core material has been injected is vacuum degassed as shown in FIG. 8(c), and then placed back into the electric furnace and held in the electric furnace at a predetermined temperature for a predetermined time to heat and harden the epoxy resin of the core material. Next, in step S22 shown in FIG. 7, the core forming split mold 30, inside which the epoxy resin has been heated and cured, is removed from the electric furnace to the outside, cooled, and then demolded to produce the epoxy resin core 20 without a parting line shown in FIG. 8(a). In this way, a core 20 without a parting line can be obtained, which eliminates the need for the above-mentioned process and work of smoothing out the irregularities resulting from the parting line of the core 20 and mirror-finishing the outer surface 20a of the core 20. This eliminates labor-intensive work that requires time and effort.

[0047] The inventors performed non-contact optical profile measurement using the coherence correlation interferometry method on the outer surface 20a of the core 20 produced in this manner, using the non-contact three-dimensional roughness measuring device described above. The measurement results are shown in Figures 9(a) to (d). Figures 9(a)-(b) show two profiles obtained by measuring 10 locations on the side of the outer surface 20a of core 20 using non-contact optical profile measurement using the coherence correlation interferometry method described above, and Figures 9(c)-(d) show two profiles obtained by measuring four locations on the top surface of outer surface 20a of core 20. The vertical axis of these figures is the height of the irregularities (μm), and the horizontal axis of Figures 9(a)-(d) is the length (mm) in the horizontal or vertical direction.

[0048] The profile shown in Figure 9(a) had a gentle undulation of 500-700 nm in the range of 50-70 μm. The profile shown in Figure 9(b) had a sharp peak, and when enlarged, it had a width of 2 μm and a height of 800 nm, which was close to a sphere. However, when ten points on the inner side of the outer surface 20a of the core 20 were measured, the profiles of six points had gentle undulations without any sharp peaks, as shown in Figure 9(a), while the profiles of the remaining three points, excluding the profile shown in Figure 9(b), had peaks, but the spread was more than 10 times the height, making it possible to image them.

[0049] The profile shown in Figure 9(c) was smooth with no protrusions over 390 nm in height, while the profile shown in Figure 9(d) had one peak, which, when enlarged, was 2 μm wide and 1.4 μm high, with a height-to-width ratio close to 1:2. However, when the top four points of the outer surface 20a of the core 20 were measured, the profile of the remaining two points had a peak shape resembling scratches, but the unevenness was kept to 300 nm or less.

[0050] As is clear from these figures, the outer surface 20a of the core 20 is generally smooth, and the number of irregularities of a size equivalent to the particle diameter (780 nm to 390 nm) at which Mie scattering occurs for light of 1310 nm in spherical particles is 0 or less in Figures 9(a) and (c), and 1 in Figures 9(b) and (d), so even when other locations are taken into consideration, the number is 0 to 3. Therefore, it is preferable that the smoothness 20a of the outer surface of the core 20 is set to 390 nm or less, at which the irregularities present on the outer surface 20a do not cause Mie scattering in spherical particles and the inside of the tube can be imaged by imaging with an optical coherence tomography imaging device.

[0051] Next, a manufacturing process for the body cavity model tube of the present invention will be described with reference to FIG. 7 and FIGS. 10(a) to (c). Figure 10(a) is a perspective view showing the arrangement of an upper die, a core, and a lower die of a tube production mold, Figure 10(b) is a perspective view showing the production of a body cavity model tube using the tube production mold and core shown in Figure 10(a), and Figure 10(c) is a perspective view showing the state in which the core is dissolved and removed using an appropriate solvent from a body cavity model tube having a core disposed therein, the body cavity model tube being produced using the tube production mold shown in Figure 10(b). Thus, FIGS. 10(a) to (c) show the steps of producing the tube 10 by a molding press.

[0052] First, in step S24 shown in FIG. 7, as shown in FIG. 10(a), the core 20 produced in step S22 and shown in FIG. 8(a) and a tube production mold 40 are prepared. The tube production mold 40 is made of alloy and is a top-bottom split mold (left and right in the drawing) consisting of an upper mold 42 and a lower mold 44 formed in a substantially rectangular parallelepiped shape. The inner surfaces 42a and 44a of the upper mold 42 and the lower mold 44, which are the split surfaces of this top-bottom split mold, are respectively formed with half vertical split recesses 42b and 44b along the outer wall of the tube 10 to be produced. The recesses 42b and 44b are portions into which the tube material for forming the tube 10 is filled. Therefore, when the upper mold 42 and the lower mold 44 are fitted together with the inner surfaces 42a and 44a, which are the split surfaces of each other, the recesses 42b and 44b come together to form a material-filled cavity 46 along the outer wall of the tube 10. The core 20 is disposed between the upper die 42 and the lower die 44 of the tube manufacturing die 40, aligned with the recesses 42b and 44b.

[0053] Next, in step S26 shown in FIG. 7, silicone resin material 48, which is a tube material having a predetermined viscosity, is disposed on each of the inner surfaces 42a and 44a of the upper mold 42 and the lower mold 44, and aligned so as to cover the recesses 42b and 44b, as shown in FIG. 10(b). Next, core 20, which will be the core material, is positioned in alignment with recesses 42b and 44b of upper die 42 and lower die 44, and a pressing force is applied from the outside to the inside of both upper die 42 and lower die 44, i.e., in the direction shown by the arrows, in a sandwiched state so that pressure is applied to the mating surfaces of inner surfaces 42a and 44a, which form the dividing surfaces of upper die 42 and lower die 44. Note that gripping margins 26, 27, and 28 of core 20 can be used to align core 20 with recesses 42b and 44b of upper die 42 and lower die 44. In this state, although detailed configuration illustration and description are omitted, as shown in Patent Document 2, core 20 is positioned at the center of material filling cavity 46 in tube production mold 40 by a positioning configuration consisting of a trunk portion of the core material, which is the core, a pole extending linearly from the branch portion, and a receiving groove of the outer wall mold, which is the tube production mold, into which the pole fits, and silicone resin material 48 is disposed around core 20 according to the shapes of recesses 42b and 44b, and therefore the shape of material filling cavity 46. Although not shown, a drain is provided so that excess tube molding material can be discharged outside the mold.

[0054] Next, in step S28 shown in FIG. 7, heat is applied to the silicone resin material 48 sandwiched between the core 20 in the tube production mold 40, the recess 42b of the upper mold 42, and the recess 44b of the lower mold 44 to harden it. Then, in step S28 shown in FIG. Next As shown in Figure 10(c), when the core 20 is disposed inside the trunk portion 12 and two branch portions 14 of the tube 10, the core 20 can be removed from the tube 10 by immersing the tube together with the core in a suitable solvent, i.e., a solvent that is compatible with the core material but has little or no compatibility with the tube material, and dissolving, removing and removing only the core. When epoxy resin is used as the core material ,phase Soluble materials in HSPiP 5 th Using edition version 5.1.07, we can sort the RED values ​​between the epoxy and various solvents in ascending order. 、 You can choose the one that suits your conditions, but you can also select a mixed solvent of two or more components and determine the mixing ratio that will give you the smallest RED. Finally, the upper die 42 and the lower die 44 are separated to remove the tube 10 with the melted core 20. In this manner, the tube 10 shown in FIG.

[0055] Also, the step of removing the core 20 from the tube 10 can be performed in a state where the tube 10 is removed from the tube manufacturing die 40, as shown in FIG. That is, in step S30 shown in Figure 7, the upper mold 42 and the lower mold 44 are separated to remove the core-containing tube 10 shown in Figure 10(c), in which the core 20 is disposed inside the trunk portion 12 and the two branch portions 14 of the tube 10. Next, in step S32 shown in FIG. 7, the core 20 of the removed core-containing tube 10 is melted to produce the tube 10 shown in FIG. By thus removing the core 20 and forming the hollow portion 10a, the tube 10 shown in FIG. 1 can be manufactured. As described above, by manufacturing a body cavity model tube, it is possible to provide a tube that can eliminate image quality degradation in imaging using the OCT / OFDI guide of the present invention, and it is also possible to provide a method that can reduce the manufacturing steps for manufacturing a body cavity model tube with such characteristics and thus save time. From the above, the effects of the present invention are clear.

[0056] The body cavity model tube and the manufacturing method of the body cavity model tube of the present invention have been described in detail above with reference to various embodiments and examples. However, the present invention is not limited to these embodiments and examples, and various improvements or modifications may be made without departing from the spirit of the present invention. [Explanation of symbols]

[0057] 10, 10A, 10B, 10C, 10D Body cavity model tube (tube) 10a, 12a, 14a Hollow part 10b, 12b, 14b Inner wall surface 12, 22 trunk 14, 14A, 24 Branches 20 Core 20a outer surface 26, 27, 28 Grab it 30 Core molding split mold 32, 34 mold 32a, 34a inside 32b, 34b Recess 36 Material injection cavity 40 Tube manufacturing mold 42 Upper mold 44 Lower mold 42a, 44a Inside 42b, 44b Recess 46 Material injection cavity 48 Silicone Resin

Claims

1. A tube that is used together with an optical coherence tomography imaging diagnostic device for training in treatment and / or diagnosis of a disease via a body cavity, planning and / or research of a strategy for the treatment and / or diagnosis, and development and / or evaluation of a medical device used for the treatment and / or diagnosis, has flexibility and elasticity that models the body cavity, and is determined according to the optical coherence tomography imaging diagnostic device, The inner wall surface of the tube has a smoothness in which unevenness present as a waviness or inclination of the base of the inner wall surface is within a range of ±2.0 μm, the rate of change of the unevenness is 0.040 or less in a horizontal cross section and a vertical cross section, and the number of particulate unevenness present on the inner wall surface that is equal to or greater than half the value of 2 / π of the wavelength of a specific light used in the optical coherence tomography imaging diagnostic device, or the shorter wavelength of light having a wavelength range, is 20 or less per 335 μm x 335 μm.

2. 2. The body cavity model tube according to claim 1, wherein the tube is a branched tube having a branched shape including a trunk portion and at least one branch portion branched off from the trunk portion.

3. The body cavity model tube according to claim 2, wherein the branching shapes include a Y-shape, a T-shape, a U-shape, and repetitions and / or combinations of these shapes, and when the body cavity is a blood vessel, a branching shape derived from a living body that can be obtained based on angiography data.

4. The body cavity model tube according to any one of claims 1 to 3, wherein the body cavity is a blood vessel, and the tube is a blood vessel model that enables imaging by an optical coherence tomography imaging diagnostic device.

5. A body cavity model tube described in any one of claims 1 to 4, wherein the inner wall surface of the tube has an unevenness that exists as a wavy or inclined base of the inner wall surface within a range of ±1.5 μm, and the rate of change of the unevenness is 0.030 or less in a horizontal cross section and a vertical cross section.

6. A method for producing a body cavity model tube according to any one of claims 1 to 5, comprising the steps of: a liquid obtained by adding a solvent compatible with a thermosetting coating material that is incompatible with the core material to the inner surface of a core forming split mold into which a core material is injected to form a hollow portion of the tube and adjusting the viscosity to 0.05 to 5 Pa·s is sprayed onto the inner surface of the core forming split mold to eliminate any fitting gaps in the core forming split mold, and then the core material is injected into the core forming split mold to produce the core; A method for manufacturing a body cavity model tube, comprising the steps of: manufacturing the tube by a molding press method using the manufactured core and a tube manufacturing die.

7. The method for manufacturing a body cavity model tube according to claim 6, wherein the smoothness of the outer surface of the core is set to 390 nm or less, at which any irregularities present on the outer surface will not cause Mie scattering in spherical particles and imaging of the inside of the tube will be possible by imaging with an optical coherence tomography imaging device.

8. spraying the liquid having the adjusted viscosity onto a cavity surface into which the core material is injected on the inner surface of each of the two or more molds constituting the core-forming split mold; and The two or more molds are fitted together, and the coating materials on the inner surfaces are joined together to produce the core forming split mold in a state in which there is no fitting gap between the two or more molds; The core mold is placed in an electric furnace to harden the coating material, and then Injecting the core material into the core mold and hardening it; The core having a surface coated with the coating material is removed from the core molding split mold. The method for producing a body cavity model tube according to claim 6 or 7, wherein the core is produced by peeling off the coating material that covers the core.

9. After the coating material applied to the inner surface of the core forming split mold is hardened, The core molding split mold is set in a vacuum casting machine, and after vacuuming, 9. The method for manufacturing a body cavity model tube according to claim 8, further comprising the steps of: injecting the core material into the core molding mold, degassing the core material, placing the core material in the electric furnace, thermally hardening the core material, removing the core material from the electric furnace, and cooling the core molding mold. Then, the core material is removed from the core molding mold.

10. The method for manufacturing a body cavity model tube according to any one of claims 6 to 9, wherein the compatibility between the coating material and the core material, and the compatibility between the coating material and the solvent are evaluated by Hansen Solubility Parameter (HSP).

11. The incompatibility between the coating material and the core material means that the center of the Hansen solubility parameter (HSP) of each of them is outside the sphere of the interaction radius of the other in the Hansen space, The method for manufacturing a body cavity model tube according to claim 10, wherein compatibility between the coating material and the solvent means that in the Hansen space, the center of the Hansen solubility parameters (HSP) of each of the coating material and the solvent is inside a sphere of the interaction radius of the other.

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