JP5194214B2 - Rectal deaerator - Google Patents

Description

  The present invention relates to a rectal deaerator used for radiation therapy of prostate cancer.

  Prostate cancer accounts for 5.4% of Japanese males with malignant tumors and 4.2% of deaths from malignant tumors. is there.

  Surgery and radiation therapy are performed as radical treatment for prostate cancer. The biochemical disease-free survival rate (disease-free survival rate based on blood biochemical test results) in normal radiation therapy for prostate cancer is 87% and 56% for the low-risk group, medium-risk group, and high-risk group, respectively. 37%. Of the adverse events caused by radiotherapy, the frequency of Grade 2 or higher proctitis, which is the most common, is 10%.

  Recently, various new radiotherapy techniques such as proton therapy have emerged, and the effect of treatment has been improved and the toxicity has been reduced, but in order to further improve the effect of radiotherapy and reduce adverse events, the prostate It is necessary to administer a high dose and suppress the dose of normal organs such as the rectum.

  In prostate cancer radiation therapy, radiation is applied to the prostate and sometimes to the seminal vesicles (located behind the prostate). These organs are identified by CT or the like, and the site and volume to be irradiated are defined. It is known that the relative positional relationship between the prostate and the pelvic bone of the seminal vesicle varies greatly. In actual treatment, the volume of the prostate and the seminal vesicle itself is irradiated with a volume of 5 to 10 mm. 1 is a portion surrounded by a dotted line). This increases the irradiated volume of the rectum and increases the frequency of injury.

  As one of the causes of fluctuations in the position of the prostate, fluctuations in the volume of the rectum due to gas and stool (FIG. 2) have been pointed out. In other words, when the rectum is full, the ventral side (front) of the rectum is pressed against the back of the prostate, and the prostate itself is displaced forward. As a result, effective irradiation cannot be performed, and radiation may be irradiated to the rectum.

  As the measurement value of the forward displacement dimension of the prostate accompanying the change in the rectal volume, the forward displacement dimension of the prostate when the rectal volume is 140 ml is 3.3 mm, and the prostate when the rectal volume is 80 ml. Data that the forward displacement dimension of the prostate is 1.6 mm, the forward displacement dimension of the prostate when the rectal volume is 60 ml is 1.4 mm, and the forward displacement dimension of the prostate when the rectal volume is 40 ml is 0.2 mm It has been confirmed that the amount of forward displacement of the prostate is easily affected by the increase or decrease in rectal volume.

  Therefore, in order to make the volume of the rectum located behind the prostate constant, a method is known in which a balloon inflated to about 60 to 80 ml is placed in the rectum (FIG. 3) for treatment (Non-Patent Document 1). ).

  This method increases the reproducibility of the prostate position and can be treated with a volume that gives the main body of the prostate a small margin, and it is expected to reduce the rectal dose. However, because the intrarectal volume is increased by the rectal balloon, the rectal ventral surface (front surface) is pressed against the prostate, and the volume of the rectum near the prostate may increase, causing damage to the mucous membrane and discomfort due to the treatment. There is. In addition, if the volume of the balloon is too larger than the rectal volume, it may cause adverse effects due to the forward displacement of the prostate and the risk of radiation irradiation to the rectum as well as the filling of the gas in the rectum. It has been confirmed that it is not effective.

  It should be noted that the state in which the gas in the rectum, which is a problem at the time of radiation treatment, is filled with gas, causes displacement of the position of the organ near the rectum. Therefore, in other therapeutic purposes and treatment plans other than prostate cancer treatment However, it also interferes with standard organ location confirmation in X-ray fluoroscopy, CT imaging, etc., and therefore development of a medical device that can efficiently extract gas in the rectum by a simple operation is desired. Yes.

van Lin EN, The effect of an endorectal balloon and off-line correction on the interfraction systematic and random prostate position variations: a comparative study, Int. J. Radiat. Oncol. Biol. Phys. 2005 Jan 1; 61 (1): 278-88.

  An object of the present invention is to provide a medical device that can reduce rectal disorders caused by radiation irradiation in prostate cancer treatment and a medical device that can efficiently extract gas in the rectum by a simple operation.

  If the volume of the rectal lumen is small (Fig. 2, left), the distance between the rectal ventral surface and the prostate can be increased, so that radiation such as radiation to the prostate is concentrated and effective, and the radiation dose to the rectum can also be reduced. However, defecation and gas conditions are constantly changing and may also change during irradiation. The present inventor has noticed that there is a lot of gas by fluoroscopy at the time of treatment planning and at the start of treatment (FIG. 2, right). However, it is difficult to intentionally excrete gas, and even if the gas can be excreted, it may be excreted together with the gas excretion, and as a result, the volume of the bladder may fluctuate and the prostate may be displaced. There is.

  Therefore, the present inventor inserts a tube into the rectum (FIG. 4), enables CT imaging for treatment planning in a state where the contents of the rectum are actively removed, prevents irradiation of the rectum, A method for effective treatment with proton beam has been developed. That is, if a state with a small amount of rectal contents can be reproduced by this method, the displacement of the prostate is minimized, and a treatment in a state where the rectum is separated from the posterior wall of the prostate is possible. In this method, when the distance between the posterior wall of the prostate and the ventral side of the rectum (front surface) is small, the bending diameter from the distal end portion to the middle portion of the deaeration tube is varied (the bending is deepened), and the rectum. A device has been developed that allows the posterior wall to be pushed backwards (caudal bone side) to create a distance between the back of the prostate and the ventral side of the rectum (front).

That is, the gist of the present invention is as follows.
(1) A rectal degassing tube that is inserted into the rectum during radiation therapy for prostate cancer and used to reduce the dose irradiated to the rectum.
(2) The rectal deaeration tube according to (1), which is a tube-shaped object having a distal end blockage and a proximal end opening made of a flexible material and has a deaeration hole on the tube wall surface.
(3) The rectal deaerator as described in (1) or (2) above, wherein the deaeration holes are symmetrically arranged in parallel on the side located on the human abdomen side when inserted into the rectum.
(4) It is a tube-shaped object with a distal end occlusion and a proximal end opening made of a flexible material, and when inserted into the rectum, the deaeration holes are symmetrically arranged in parallel on the side located on the human abdomen side. A rectal degassing tube that is used to insert into the rectum and evacuate the rectum.
(5) The rectal degassing tube according to any one of (2) to (4), wherein the flexible material is a thermoplastic resin.
(6) The rectal deaerator according to any one of (2) to (5), wherein the flexible material contains a contrast agent.
(7) The rectal deaeration tube according to any one of (2) to (6), which has a plurality of deaeration holes in a range of 90 mm from the distal end.
(8) The 1st bending part distribute | arranged to 40-90 mm from the front-end | tip, the 2nd bending part and the 2nd bending part which have a curve of the reverse direction to the 1st bending part distribute | arranged 30-30 mm from the 1st bending part (1) to (7), in which the third bending portion having a curvature in the direction opposite to the second bending portion arranged at 30 to 100 mm has a curved portion arranged to form an S shape. A rectal deaerator according to any one of the above.
(9) The rectal deaeration tube according to (8), wherein the third curved portion includes a straight portion.
(10) The rectal deaerator as described in (8) or (9) above, wherein the radius of curvature of the first curved portion is 20 to 60 mm and the radius of curvature of the second curved portion is 10 to 30 mm.

(11) The rectal deaeration tube according to (10), wherein the curvature radius of the third bending portion is 10 to 50 mm.
(12) The rectal deaeration tube according to any one of (8) to (11), wherein the first bending portion has a plurality of deaeration holes.
(13) The length marking that makes it possible to determine the insertion length into the rectum and / or the directionality of the deaeration hole is printed along the length direction, according to any one of (1) to (12) Rectal deaeration tube.
(14) A medical device including the rectal degassing tube according to any one of (1) to (13) and an insertion inner tube that can be inserted into the inner diameter side of the rectal degassing tube.
(15) The medical device according to (14), wherein the inner cylinder for insertion is a tube-shaped object having both ends open.
(16) The medical device according to (14) or (15), which is used for reducing rectal damage caused by irradiation in prostate cancer treatment.
(17) The medical device according to (14) or (15), which is used for extracting gas from the rectum.
(18) A rectal degassing tube according to any one of (1) to (13) above, and an inner cylinder used by being inserted into the inner diameter side of the rectal degassing tube inserted into the rectum, A medical device including a contrast insertion inner tube made of a flexible material.
(19) An inner cylinder which is inserted into the rectum and used by being inserted into the inner diameter side according to any one of the above (1) to (13), which is made of a flexible material containing a contrast agent. Insert inner cylinder.

  According to the present invention, the rectal disorder caused by irradiation in prostate cancer treatment is reduced, and the gas in the rectum is filled with gas by efficiently removing the gas in the rectum by a simple operation. It is possible to prevent the displacement of the position of the organ near the rectum.

  The rectal degassing tube of the present invention is inserted into the rectum at the time of radiotherapy for prostate cancer, and is used for reducing the dose irradiated to the rectum. It is a medical device used to reproduce the state of low rectal content and to minimize the displacement of the prostate by positively removing.

  Therefore, the rectal degassing tube of the present invention can be inserted into the rectum and has any shape as long as it has at least one deaeration hole. From the point that makes it possible to create a distance between the back of the prostate and the ventral side of the rectum (front), even when sufficient distance from the (front) is not obtained, from the tip of the degassing tube to the middle It is preferable to form a curved portion, and it is more preferable to form a curved portion in which the first curved portion and the second curved portion are arranged so as to form an S shape from the tip, and a position following the second curved portion. It is most preferable to provide a third bending portion having a curvature in the direction opposite to the second bending portion. Moreover, in the said curve part, the curvature radius of a 1st curved part is 20-60 mm normally, Preferably it is 30-45 mm, The curvature radius of a 2nd curved part is 10-30 mm normally, Preferably it is 12-20 mm, 3rd curve The radius of curvature of the part is usually 10 to 50 mm, preferably 25 to 40 mm, the length of the first curved part is usually 40 to 90 mm, preferably 60 to 80 mm, and the length of the second curved part is usually 30. -50 mm, preferably 35-45 mm, and the length of the third curved portion is usually 30-100 mm, preferably 50-70 mm. Note that the third bending portion may not be completely curved, and may be, for example, one that is processed into a straight line from the middle of the curvature, or one that includes a straight portion, and the second bending portion. It may be a rectal deaeration tube having a shape that is directly guided straight from the curved portion.

  The curved portion is preferably designed so that a distance of 5 to 10 mm can be created between the posterior surface of the prostate and the ventral side (front surface) of the rectum when the rectal deaeration tube of the present invention is inserted into the rectum. .

  The outer diameter of the rectal degassing tube of the present invention is usually 4 to 14 mm, preferably 7 to 10 mm, the inner diameter is usually 2 to 8 mm, preferably 3 to 6 mm, and the length is the length of a human rectum. In view of the positional relationship with the prostate gland and the insertion operability, it is usually 100 to 400 mm, preferably 150 to 350 mm, and more preferably 220 to 280 mm.

  The rectal degassing tube of the present invention is preferably a tube-like product having a distal end occlusion and a proximal end opening from the viewpoint of ease of insertion into the rectum and deaeration functionality.

  The rectal deaeration tube used for insertion into the rectum of the present invention and venting the gas in the rectum is a tube-like product with a closed end and a proximal end, so that it can be easily inserted into the rectum and the gas in the rectum Can be efficiently removed by a simple operation.

  The purpose of degassing the rectal degassing tube is to form a gap between the rectal ventral side and the prostate, so it is necessary to efficiently vent the rectal ventral side (prostate side). Therefore, the position of the deaeration hole of the rectal deaeration tube is preferably located on the side located on the human abdomen side when the deaeration tube is inserted into the rectum. In order to enhance the degassing effect, the deaeration hole starts from a portion parallel to the position of the human upper bladder when the rectal degassing tube is inserted into the rectum, and is parallel to the position of the lower prostate of the human. It is preferable to provide a plurality of them so as to be positioned between these portions, and it is more preferable to provide them symmetrically when viewed from the human abdomen side.

  As described above, the rectal degassing tube of the present invention is more effective when it has a plurality of deaeration holes positioned on the human abdomen when the deaeration tube is inserted into the rectum. As a result of clinical trials, 4 to 8 results were almost achieved, but preferably 6 to 12 and more preferably 8 to 12 deaeration holes. Is. The size and shape of the deaeration hole are not particularly limited as long as the deaeration effect can be obtained and the patient does not cause pain or other discomfort at the time of rectal insertion, but has a longitudinal direction in the rectal insertion direction. It is preferably an oval shape, free of by-products such as burrs, and excellent surface smoothness. It is effective to provide a plurality of deaeration holes at least near the tip, that is, at a position from the tip to 90 mm, preferably in the first curved portion, for example, 4 to 8, preferably 6 to 12, more preferably 8 to 12. It is.

  In the rectal degassing tube of the present invention, it is preferable to print a length marking along the length direction that makes it possible to determine the insertion length into the rectum and / or the directionality of the deaeration hole. This length marking is preferably provided on the side opposite to the deaeration hole located on the human abdomen side when the deaeration tube is inserted into the rectum (located on the human back side behind the deaeration hole). Normally, the operation of inserting the rectal deaeration tube into the rectum is performed from the back side of the human, so that the insertion length of the deaeration tube and the direction of the deaeration hole can be easily determined when viewed from the back side.

  The material constituting the rectal degassing tube of the present invention is not particularly limited as long as it is a material that has a strength that can be inserted into the rectum, is flexible, and has excellent surface smoothness. The rectal degassing tube provided with a portion is inserted into the inner diameter side of the rectal degassing tube and the inner cylinder for insertion is deformed substantially linearly to facilitate insertion into the rectum. In the curve restoration property when moved to the rectal degassing tube opening side, a flexible material, for example, a thermoplastic material, or a material having flexibility such as silicone rubber, urethane rubber or other vulcanized rubber is preferable, flexibility, A thermoplastic elastomer is more preferable from the viewpoints of resilience, surface smoothness, and visibility (transparency) with respect to the inner cylinder for insertion described later.

  Examples of the thermoplastic elastomer include polyurethane-based thermoplastic elastomer, polystyrene-based thermoplastic elastomer, polyolefin-based thermoplastic elastomer, polyester-based thermoplastic elastomer, polyamide-based thermoplastic elastomer, preferably polyurethane-based thermoplastic elastomer, polyolefin-based thermoplastic. An elastomer is mentioned.

  The hardness of the flexible material, such as a thermoplastic resin, is preferably Shore A 80-95, more preferably Shore A 83-90.

  As long as the object of the present invention is not impaired, the flexible material may be a conventional additive such as an inorganic filler (calcium carbonate, talc, titanium oxide, silica, clay, Barium sulfate, magnesium carbonate, etc.), inorganic or organic fibrous material (glass fiber, carbon fiber, aramid fiber, etc.), stabilizer (heat stabilizer, antioxidant, light stabilizer), tackifier, antistatic agent, It may contain a lubricant, a foaming agent, a colorant and the like.

  In addition, by adding a contrast medium that allows the main rectal degassing tube to be imaged by X-ray fluoroscopy or CT imaging, the main material is a flexible material, so that the insertion state and position can be confirmed from outside the human body. Can be discriminated. The contrast agent used here is not limited as long as it is used for imaging for X-ray fluoroscopy and CT imaging, and is not harmful to the human body and can provide a shielding effect equivalent to that of a human bone. Inorganic fillers such as sulfate, aluminum sulfate, bismuth carbonate and bismuth oxide, silver and iodine, etc. are used. For the purpose of contrast only, a method of embedding a metal wire in the tube without blending a contrast agent in the material of the rectal degassing tube, or placing the metal wire or gauze in the rectal degassing tube It is also possible to use a method of inserting and contrasting.

  In the rectal degassing tube of the present invention, among the above options, it is harmless to the human body, has a high contrast effect, is excellent in compatibility with the flexible material as the main material, and impairs the flexibility and mechanical properties of the main material. For reasons that do not exist, a method using an inorganic filler as a contrast agent is preferable, and a method of adding barium sulfate certified as being used for in vivo clinical use and guaranteed to be non-toxic is more preferable. The blending ratio of barium sulfate varies depending on the product size (outer diameter), but when blended into the rectal degassing tube of the present invention, the discrimination effect by X-ray fluoroscopy or CT imaging, CT value equivalent to human bone From the viewpoint of preventing halation of CT images, the content is usually 1 to 20% by mass, preferably 2 to 10% by mass, and more preferably 4 to 6% by mass with respect to the flexible material as the main material.

  The rectal degassing tube of the present invention is preferably formed by extruding a resin raw material into a tube shape, cutting it to a required length, processing the tip into a hemispherically closed state by heat fusion, and then applying heat and press It can manufacture by performing the deaeration process of a side surface side, and forming a curve part by heating and quenching using a bending process metal mold | die.

  In order to insert the rectal degassing tube of the present invention into the rectum, an inner tube for insertion is inserted on the inner diameter side of the rectal degassing tube, and the rectal degassing tube having a curved portion is deformed substantially linearly. It can be inserted into the rectum. Next, the required amount of the inner cylinder for insertion is moved to the opening side in the rectal degassing tube, and then the movement is stopped so that the gas in the rectum is almost discharged outside the body via the deaeration hole. It becomes possible. When it is difficult for gas to escape, the content of the rectum is reduced by degassing with a syringe or the like from the inner diameter side of the inner cylinder for insertion. In addition, by moving the insertion tube toward the opening in the rectal degassing tube or withdrawing it, the curved portion of the rectal degassing tube returns to the state before the insertion tube was inserted, and the prostate It becomes possible to make a sufficient distance between the posterior surface and the anterior rectal side, the anterior rectum is fixed away from the posterior surface of the prostate, and the radiation dose to the rectum and the dose of proton beam can be reduced. As a result, damage to the rectal mucosa caused by radiation or proton beams can be suppressed, and adverse effects such as rectal disorders can be prevented.

  The insertion inner cylinder is not limited in material, shape, etc., as long as it enables the above, but as the material of the insertion inner cylinder, preferably, the rectal deaeration tube is linearly deformed. Fluorine resin, silicone resin and ethylene vinyl alcohol copolymer resin (saponified ethylene vinyl acetate copolymer: EVOH) with sufficient hardness, excellent surface smoothness, low frictional resistance, and good insertability The shape is usually a tube-like product having openings at both ends, but from the viewpoint of post-treatment of the device after treatment, an ethylene vinyl alcohol copolymer resin excellent in environmental characteristics is particularly preferable.

  The inner cylinder for insertion can be manufactured by forming a resin into a tube shape by an extruder and cutting it into a required length.

  The rectal degassing tube of the present invention is usually manufactured and sold as a medical device combined with the insertion inner tube, but only the rectal deaeration tube is manufactured and sold separately, and the insertion inner tube is available separately. It is also possible to use a proper one.

  In addition, as a method for making it possible to determine the insertion state of the rectal degassing tube into the rectum by fluoroscopy or CT imaging, the method of inserting the metal wire or gauze into the rectal degassing tube is exemplified. However, the metal wire is too hard and the shape of the rectal degassing tube itself is impaired, and in the case of gauze, there is a risk that a residue may remain in the body, making it impossible to employ it.

  Therefore, as described above, the present inventor has devised a method of adding a contrast medium such as barium sulfate to the main raw material forming the rectal deaeration tube. However, in the treatment site, X-ray fluoroscopy and CT imaging are always required. In particular, the effect of printing the above-mentioned insertion marking makes it possible to recognize the direction of the degassing tube and the insertion length, so it is necessary to add a contrast agent to all rectal degassing tubes themselves There was a tendency to occur even when there was no.

  Therefore, the present inventor, as a method for enabling X-ray fluoroscopy and CT imaging when a contrast agent is not added to the main raw material forming the rectal deaeration tube, as an alternative to eliminate the drawbacks of the metal wire, An internal tube for contrast enhancement has been devised that does not change the shape of the trachea. That is, a flexible material that is the same as or slightly harder than the rectal deaeration tube, such as a material in which a contrast medium is blended in a thermoplastic resin, is used to extrude a tube having an outer diameter sufficiently smaller than the inner diameter of the deaeration tube The insertion tube for contrast enhancement can be manufactured by molding with a machine and cutting to a required length.

  The inner tube for imaging according to the present invention is inserted into the deaeration tube after the rectal deaeration tube is inserted into the rectum, so that it follows the shape of the deaeration tube. By using X-ray fluoroscopy and CT imaging techniques, The insertion state and position of the deaeration tube can be determined from the outside of the human body. Although the tube outer diameter of the inner tube for contrast enhancement is sufficiently smaller than the inner diameter of the deaeration tube, it is usually 1.2 to 4.0 mm, preferably 1.5 to 3.0 mm, more preferably 1.8 to The inner diameter of the inner tube for contrast enhancement is selected within the range of 0.6 to 2.0 mm according to the outer diameter as long as it does not interfere with gas venting. The material hardness of the inner tube for contrast enhancement is slightly harder than the material hardness of the deaeration tube, so that the operability of insertion is better. Usually, Shore A83 to 95 is preferable, and Shore A85 to 90 is more preferable. . In addition, the blending ratio of the contrast agent such as barium sulfate to the flexible material, which is the main material of the contrast inner tube, is smaller than the rectal degassing tube, so it is desirable to increase the blending ratio. The amount is usually 5 to 20% by mass, preferably 10 to 15% by mass, based on the main material.

  Even if no contrast agent is blended in the main material of the rectal degassing tube, the use of the contrast insertion inner cylinder of the present invention enables X-ray fluoroscopy and CT imaging as necessary, which is convenient. And in terms of cost (contrast-containing material is expensive).

  The rectal degassing tube of the present invention not only reduces rectal damage (damage of the rectal mucosa) in the high-concentration proton beam treatment used for prostate cancer treatment, but also general radiation with poor dose concentration. It is thought to greatly contribute to the reduction of rectal disorders by treatment (X-rays, γ-rays).

  In order to describe the present invention more specifically and in detail, examples are shown below, but the present invention is not limited to these examples.

Example 1
(1) Creation of an average rectal shape model An average rectal shape model was created based on CT images of 15 prostate cancer proton therapy patients. The average rectal / anal curvature of the 15 cases and the desired curvature of the rectal deaerator estimated based on the curvature are shown in FIG.

(2) Production of rectal deaeration tube Using a polyurethane thermoplastic elastomer for medical use (hardness: Shore A85) and a polyolefin thermoplastic elastomer for medical use (hardness: Shore A86), respectively, using a single layer extruder A tube having an outer diameter of 8 mm and an inner diameter of 4 mm was formed. Thereafter, the formed tube was cut into a length of 250 mm, and then the tip of the tube was processed into a hemispherical block (curvature radius: 4 mm) by heat sealing to form a linear tube with a closed end and a proximal end. After that, at the position of 10mm, 25mm and 40mm from the tip, punching of each two deaeration holes (oval with 2mm width and 5mm length) by heat and press punching process, the straight tube before curve forming Produced (Fig. 6).

  Based on the desired curvature of the rectal degassing tube shown in FIG. 5, the first curved portion (curvature radius 40 mm), the second curved portion (curvature radius 18 mm), and the third curved portion (curvature radius 28 mm) are S-shaped from the tip. An aluminum bending mold provided with a curved portion so as to form a film was manufactured (FIG. 7).

  After the linear tube is set in the bending mold, it is placed in a thermostatic bath, heated for a certain period of time under an appropriate temperature condition, and then rapidly cooled with cooling water, thereby bending the linear tube. And a curved portion in which the first curved portion (curvature radius 40 mm), the second curved portion (curvature radius 18 mm), and the third curved portion (curvature radius 28 mm) are arranged so as to form an S shape from the tip. A rectal deaeration tube having

Note that the third bending portion described above may not be completely curved, and may be, for example, a rectal deaeration tube processed linearly from the middle of the curvature as shown in FIG. It may be a rectal deaeration tube having a shape that is directly guided straight from two curved portions.
In FIGS. 6, 7 and 8, the unit of numerical values is mm unless otherwise specified.

(3) Manufacture of the inner cylinder for insertion The resin material of the inner cylinder for insertion is an ethylene vinyl alcohol copolymer resin (ethylene vinyl acetate) that has the required hardness, excellent surface smoothness, low frictional resistance, and excellent environmental characteristics. Copolymerized saponification product: EVOH hardness: Rockwell M88 ethylene copolymerization ratio 44 mol%) was selected.

  Using the EVOH resin, a tube having an outer diameter of 3.1 mm and an inner diameter of 1.5 mm was molded and cut to a length of about 350 mm to produce an inner cylinder for insertion.

  The cutting length is not particularly limited as long as it has good operability with respect to the rectal degassing tube when the inner tube for insertion is inserted, moved, and removed. In addition, for the purpose of improving the operability at the time of insertion or movement, it is possible to add taper processing or round processing to the tip of the insertion inner cylinder if it is effective.

Example 2
(1) Production of Rectal Degassing Tube Containing Contrast Agent As a contrast agent that enables X-ray fluoroscopy and CT imaging in a raw material of a polyurethane-based thermoplastic elastomer for medical use (hardness: Shore A85), the ratio relative to the main material is 1 to 20 A tube having an outer diameter of 8 mm and an inner diameter of 4 mm was formed using a single layer extrusion molding machine using a material in which barium sulfate was blended so as to have a mass%. After the extruded tube was sufficiently cooled in a cooling water tank in the molding line, length markings were previously printed at a predetermined pitch as shown in FIG. 10 by an ink jet printer (FIG. 10). After the tube tip clogging process performed in a later step, the tube on which the length marking is printed, as shown in FIG. 10, the tip portion “0” mark is arranged just 12 mm from the tube tip portion. While adjusting the length, the tube was cut between a length of about 250 to 260 mm (FIG. 10).

  Thereafter, the tube tip was processed into a hemispherical block (curvature radius 4 mm) by heat-sealing to form a linear tube with a closed end and a proximal end. At this time, it is preferable that the “0” printing position of the length marking is just 12 mm from the closing tip, and the total length of the tube is 250 mm (FIG. 10). As shown in FIG. 9, the tube subjected to the tip closing process is arranged in parallel by heat and press punching at positions of 12 mm, 27 mm, 42 mm, 57 mm and 72 mm from the tip from the back side of the length marking. A deaeration hole (an ellipse with a width of 2 mm and a length of 7 mm) was punched out to produce a straight tube before curve forming (FIG. 9).

  Next, in the same manner as in Example 1, the first curved portion (curvature radius 40 mm), the second curved portion (curvature radius 18 mm), and the third curved portion (curvature radius 28 mm) form an S-shape from the tip. The straight tube (FIGS. 9 and 10) is set in an aluminum bending mold (FIG. 7) provided with a curved portion, and appropriate heating and cooling conditions are added to form an S-shape. A rectal deaeration tube having a curved portion arranged so as to form a tube was manufactured (FIG. 11).

(2) Effect of blending ratio of barium sulfate blended as contrast medium on fluoroscopy and CT imaging The rectal degassing tube manufactured in (1) above is the same as the insertion cylinder manufactured in Example 1 (3). As a result of examining the influence of the compounding ratio of barium sulfate on X-ray fluoroscopy and CT imaging, using a material blended with barium sulfate so that the ratio to the main material is 5% by mass The tube was molded and the best results were obtained by X-ray fluoroscopy and CT imaging. Also, the CT value was about 800, which was almost equivalent to a human bone, and a value that was easy to distinguish was obtained.

Example 3
(1) Production of rectal deaeration tube containing no contrast agent Using a polyurethane thermoplastic elastomer for medical use (hardness: Shore A85) used in Example 1, an outer diameter of 8 mm, A tube having an inner diameter of 4 mm was formed. The formed tube is printed with a length marking by an ink jet printer in the same manner as the tube containing the contrast medium of Example 2 (1), and similarly to the rectal degassing tube containing the contrast medium of Example 2 (1). Then, a rectal deaeration tube (with no contrast medium) having a curved portion arranged so as to form a distal hemispherical block, a deaeration process on the outer periphery of the tube, and an S-shape was manufactured.

(2) Manufacture of contrast-injection inner cylinder As a contrast agent that enables X-ray fluoroscopy and CT imaging in a polyurethane-based thermoplastic elastomer (hardness: Shore A88) raw material, the ratio to the main material is 5 to 20% by mass A tube having an outer diameter of 2.3 mm and an inner diameter of 1.2 mm was formed using a single layer extrusion molding machine using a material blended with barium sulfate. Thereafter, this tube was cut to a length of about 300 mm to produce an imaging inner tube to be inserted into the rectal deaeration tube.

(3) Effect of contrast-inserting inner tube After inserting the rectal degassing tube manufactured in (1) into the rectum using the insertion tube in Example 1 (3), the contrast-inserting tube in (2) When the inner cylinder was inserted into the rectal deaeration tube, it was possible to discriminate the insertion status and positional relationship of the rectal deaeration tube as in Example 2, and no difference in the degassing effect appeared. In addition, as a result of testing the influence of the blending ratio of barium sulfate blended as a contrast agent on fluoroscopy and CT imaging, a material blended with barium sulfate so that the ratio to the main material is 10 to 15% by mass. The tube formed by using it had a high discrimination effect, and there was no occurrence of halation of the CT image, and the best result was obtained.

It is a figure which shows the relationship between the irradiation part in the radiotherapy of a prostate cancer, a prostate, and a rectum. It is a figure which shows the state from which the position of a prostate fluctuates by the fluctuation | variation of the volume of the rectum by gas or feces. The left figure shows the state where the rectum is emptied, and the right figure shows the state where the rectum is full. It is a figure which shows the use condition of the method of indwelling and treating a balloon in a rectum. It is a figure which shows the use condition of the rectal deaeration tube of this invention. It is a figure which shows the desirable curvature of the rectal deaeration tube estimated based on the average rectal / anal curvature of 15 prostate cancer patients treated, and the curvature. It is a figure which shows the linear tube before providing the curve part of the rectal deaeration pipe | tube manufactured in Example 1, and an oval hole process part turns into a deaeration hole, and when it inserts in a rectum, it is a human abdomen side. To position. “5 ₋₀ ” and “2 ₋₀ ” indicate that less than 5 mm and less than 2 mm are not possible, and 5 mm or more and 2 mm or more are necessary, and “2-R1” indicates that the processing (molding) radius is 1 mm. Indicates that there is. It is a figure which shows the bending metal mold | die used in the Example. It is a figure which shows the bending metal mold | die in which a 3rd bending part does not form complete curvature. It is a figure which shows the linear tube before providing the curve part of the rectal deaeration pipe | tube manufactured in Example 2, and when an oval hole process part turns into a deaeration hole and it inserts in a rectum, it is a human abdomen side. To position. “7 ₋₀ ” and “2 ₋₀ ” indicate that less than 7 mm and less than 2 mm are not possible, and that 7 mm or more and 2 mm or more are necessary, and “2-R1” indicates a processing (molding) radius of 1 mm. Indicates that there is. FIG. 10 is a diagram showing a state in which a length marking is pre-printed on the back side of the rectal deaeration tube shown in FIG. 9 where the oval deaeration hole is processed, and when inserted into the rectum, Located on the back side. The character height is 2.5 mm, □ is 0.8 mm square, and the print color is black. FIG. 11 shows a completed drawing of a rectal deaeration tube in which the straight tube before curve processing shown in FIGS. 9 and 10 is set in the bending mold shown in FIG. 7 and bent through heating and cooling steps. The side where the deaeration holes are processed when inserted into the rectum is located on the human abdomen side, and the side on which the marking is printed is located on the human back side. The character height is 2.5 mm, □ is 0.8 mm square, and the print color is black. The bending shape of the rectal deaeration tube obtained by processing the straight tube of FIG. 6 is the same.

Claims (11)

A rectal deaeration tube that is inserted into the rectum during radiation therapy for prostate cancer and used to reduce the dose irradiated to the rectum, and is a tube-shaped object with a distal end occlusion and proximal opening made of a flexible material. , and the have a deaerating hole in the tube wall, the flexible material, rectal deaerating tube you containing contrast agent. Rectal, which is a tube-shaped object with a distal end occlusion and a proximal end made of a flexible material, and has deaeration holes arranged symmetrically in parallel on the side located on the human abdomen side when inserted into the rectum. A rectal degassing tube used for insertion into the rectum to degas the rectum, wherein the flexible material contains a contrast medium. A rectal degassing tube that is inserted into the rectum during radiation treatment of prostate cancer and used to reduce the dose irradiated to the rectum, and an insertion inner tube that can be inserted into the inner diameter side of the rectal degassing tube Medical tools. Rectal, which is a tube-shaped object with a distal end occlusion and a proximal end made of a flexible material, and has deaeration holes arranged symmetrically in parallel on the side located on the human abdomen side when inserted into the rectum. A medical device comprising a rectal deaeration tube used for extracting gas in the rectum by being inserted into the rectum, and an insertion inner tube that can be inserted into the inner diameter side of the rectal deaeration tube. The medical device according to claim 3 or 4, wherein the insertion inner cylinder is a tube-like object having openings at both ends. The medical device according to any one of claims 3 to 5, which is used for reducing a rectal disorder caused by irradiation in prostate cancer treatment. The medical device according to any one of claims 3 to 5, which is used for extracting gas from the rectum. A rectal degassing tube that is inserted into the rectum during radiation therapy for prostate cancer and used to reduce the dose irradiated to the rectum, and is inserted into the inner diameter side of the rectal degassing tube inserted into the rectum. A medical device including a contrast-inserting inner tube made of a flexible material containing a contrast agent. Rectal, which is a tube-shaped object with a distal end occlusion and a proximal end made of a flexible material, and has deaeration holes arranged symmetrically in parallel on the side located on the human abdomen side when inserted into the rectum. A rectal degassing tube used for extracting gas in the rectum by inserting it into the inside, and an inner cylinder used by inserting into the inner diameter side of the rectal degassing tube inserted in the rectum, containing a contrast agent A medical device including a contrast insertion inner cylinder made of a flexible material. An internal tube that is inserted into the rectum degassing tube that is inserted into the rectum during radiation therapy for prostate cancer and used to reduce the dose irradiated to the rectum, and contains a contrast medium An imaging inner tube made of a flexible material. Rectal, which is a tube-shaped object with a distal end occlusion and a proximal end made of a flexible material, and has deaeration holes arranged symmetrically in parallel on the side located on the human abdomen side when inserted into the rectum. An inner cylinder used for insertion into the rectal degassing tube used for extracting gas in the rectum and inserted into the inner diameter side of the rectal degassing tube, which is made of a flexible material containing a contrast agent .

Images