Catheter apparatus and brachytherapy system

Abstract

A catheter apparatus (10) includes a tubular member (11); multiple fluid-flow pipe members (13), each having a proximal end (19) and a distal end (18), and being disposed along a first axial direction of the tubular member; multiple node members (15) disposed along a first axial direction of the tubular member, wherein two adjacent node members (15) form a segment (1a); and a periphery member (14), wherein the periphery member (14) wraps the multiple node members (15) to form a space (1b) with the segment (1a) formed between the two adjacent node members (15). The catheter apparatus (10) can irradiate the entire diffuse tumor during one brachytherapy process without repeated placement of the catheter. Meanwhile, it can be smoothly inserted into the patient's narrow body cavity because there are no external balloons. A brachytherapy system adopts the catheter apparatus (10).

Claims

1. A catheter apparatus, comprising: a tubular member; multiple fluid-flow pipe members disposed along a first axial direction of the tubular member, wherein each of the fluid-flow pipe members has a proximal end and a distal end; one or more periphery members; and multiple node members disposed along the first axial direction of the tubular member, wherein the multiple node members are wrapped by the one or more periphery members to form a sealed space between every two adjacent node members of the multiple node members, wherein every two adjacent node members of the multiple node members are not in direct contact with each other and form a segment within the sealed space, wherein each of the multiple node members is a hollow column having a hollow space configured for the tubular member to pass through the hollow column along the first axial direction, and wherein a wall of the hollow column has multiple channels disposed thereon along the first axial direction and configured for the multiple fluid-flow pipe members to pass through the hollow column along the first axial direction.

2. The catheter apparatus according to claim 1, wherein the quantity of the periphery members is more than 1.

3. The catheter apparatus according to claim 2, wherein a quantity of the fluid-flow pipe members is more than 4; a quantity of the node members is more than 5; and a quantity of the periphery members is more than 4.

4. The catheter apparatus according to claim 1 or 2, wherein all of the proximal ends of the multiple fluid-flow pipe members are connected to one control element, and the control element is configured for individually inflating or deflating each of the periphery members.

5. The catheter apparatus according to claim 1 or 2, wherein each of the multiple fluid-flow pipe members has a control element at the proximal end thereof, and the control element is configured for individually inflating or deflating each of the periphery members.

6. The catheter apparatus according to claim 1, further comprising a connecting ring member provided outside each of the multiple node members, and each of the periphery members is connected with every two adjacent node members of the multiple node members by the connecting ring member to form the sealed space.

7. The catheter apparatus according to claim 6, further comprising an outer ring member configured for each of the periphery members to fasten with the connecting ring member.

8. The catheter apparatus according to claim 1, wherein each of the multiple node members has a protruding ring member provided outside thereof.

9. The catheter apparatus according to claim 1, wherein at least two of the fluid-flow pipe members have different lengths.

10. The catheter apparatus according to claim 1, wherein each of the multiple fluid-flow pipe members has an opening individually.

11. A brachytherapy system, comprising: a tumor imaging instrument comprising X-ray imaging, fluoroscopy, computed tomography, positron tomography, single photon emission tomography, or nuclear magnetic resonance imaging; an after-loading treatment instrument; a catheter apparatus according to claim 1 connected to the after-loading treatment instrument; and one or more radioactive sources released from the after-loading treatment instrument to the tubular member within the segment according to a determination by the tumor imaging instrument.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows the relationship between radiotherapy dose and tissue toxicity.

(2) FIG. 2 is a schematic of the radiation area and deviation of displacement of teletherapy.

(3) FIG. 3(a) is an illustrative diagram showing the balloon of a current catheter after inflation.

(4) FIG. 3(b) is an illustrative diagram showing the balloon of a current catheter before inflation.

(5) FIG. 4 is an illustrative diagram showing the structure of the catheter apparatus in one embodiment of the present application.

(6) FIG. 5 is an illustrative diagram showing different length of the fluid-flow pipe members in one embodiment of the present application.

(7) FIG. 6(a) is a three-dimensional illustrative diagram of the node member.

(8) FIG. 6(b) is a front view illustrative diagram of the node member.

(9) FIG. 6(c) is a side view illustrative diagram of the node member.

(10) FIG. 7(a) is a three-dimensional illustrative diagram of the node member with the connecting ring member.

(11) FIG. 7(b) is a front view illustrative diagram of the node member with the connecting ring member.

(12) FIG. 7(c) is a side view illustrative diagram of the node member with the connecting ring member.

(13) FIG. 8(a) is an illustrative diagram of the outer ring member in one embodiment.

(14) FIG. 8(b) is an illustrative diagram of the connecting ring member of the node member connected with the outer ring member.

(15) FIG. 8(c) is an illustrative diagram of the connecting ring member of the node member connected with the outer ring member.

(16) FIG. 9 is an illustrative diagram of the node member connecting with the outer ring member and the periphery member in one embodiment.

(17) FIG. 10(a) is a three-dimensional illustrative diagram of the node member with the outer ring member in one embodiment.

(18) FIG. 10(b) is a front view illustrative diagram of the node member with the outer ring member in one embodiment.

(19) FIG. 10(c) is a side view illustrative diagram of the node member with the outer ring member in one embodiment.

(20) FIG. 11 is an illustrative diagram of the node member with the outer ring member connected with periphery member.

(21) FIG. 12 is an illustrative diagram of the inflated periphery member.

(22) FIG. 13 is an illustrative diagram of each periphery member of the catheter apparatus of the present application inflated and deflated individually for the conformity to the tumor.

DETAILED DESCRIPTION

(23) Unless otherwise defined, all technical and scientific terms in the context represent the same meanings which a person having ordinary skill in the art comprehends with.

(24) The “catheter apparatus” of the present application can be explained according to the following description of the embodiments, which allows one skilled in the art to understand the spirit of creation and make the catheter apparatus.

(25) The modes of implementation of the present application are not limited by the embodiments.

(26) FIG. 4 shows an illustrative diagram of the catheter apparatus 10 in one embodiment of the present application. Within the catheter apparatus, there is a tubular member 11 for placing a radioactive source 12. Multiple fluid-flow pipe members 13 are disposed along a first axial direction of the tubular member 11, wherein the “first axial direction” in the embodiment of the present application is the direction by taking the length of the catheter apparatus as the axis. The catheter apparatus 10 has multiple node members 15, which are disposed along the first axial direction of the tubular member 11, wherein every two adjacent node members 15 form a segment 1a therebetween, and each segment 1a form a space 1b with the periphery member 14. Each of the multiple fluid-flow pipe members 13 has an opening 17 at the distal end 18 and an independent control element 16 at the proximal end 19. The control element can be a medical pump, syringe, or injection device in some embodiments. The control element 16 transfers the fluid into the fluid-flow pipe member 13 to reach the opening 17 (not shown in figures). The fluid appears in the segment 1a between the two adjacent node members 15 and fills a space 1b, allowing the periphery member 14 to inflate and deflate to achieve the effect of positioning. Because the position of each of the openings 17 is disposed at a different position of the segments 1a, this allows different fluid-flow pipe members 13 to transfer the fluid into different segments 1a through the openings 17, and allows each of the periphery members 14 to inflate and deflate to achieve individual adjustment of the degree of inflation and deflation.

(27) The tubular member 11, the fluid-flow pipe member 13 and the periphery member 14 are made of soft and bendable materials. The materials can be silicone, latex, plastic as PVC, PU, PP, PE, PTFE or other biocompatible materials or compositions thereof. This allows the periphery member 14 to be inflatable after being filled. The tubular member 11 and the fluid-flow pipe member 13 can be designed to have different length and diameter adapted for different body parts to be treated. The segment 1a formed between two adjacent node members 15 may also be designed to have different length according to the needs.

(28) In an embodiment of esophageal cancer, the catheter apparatus 10 can be designed to have a length of 900-1400 mm, preferably a length of 900-1200 mm. The outer diameter of the tubular member 11 can be designed to be 2-6 mm, preferably 5.3 mm; and the inner diameter can be 1-5 mm, preferably 2.0-2.1 mm, so long as a lumencath for assisting the placement of the radioactive source (not shown in figures) is able to be placed therein.

(29) In an embodiment of rectum, the catheter apparatus 10 can be designed to have a length of 300-600 mm, preferably a length of 400-600 mm. The outer diameter of the tubular member 11 can be designed to be 6-15 mm, preferably 10 mm; and the inner diameter can be 1-5 mm, preferably 2.0-2.1 mm, so long as a lumencath for assisting the placement of the radioactive source (not shown in figures) is able to be placed therein.

(30) The fluid-flow pipe member 13 is of the same length as the tubular member 11 in some embodiments, with at least one opening 17 located in a different segment 1a. The fluid-flow pipe member 13 may have an inner diameter between 0.2 and 3 mm, preferably an inner diameter of 0.7 mm. In an embodiment for esophageal cancer, the distance between the center of the fluid-flow pipe member 13 and the center of the tubular member is 0.6-3 mm, preferably 1.8-1.9 mm. In an embodiment for rectal cancer, the distance between the center of the fluid-flow pipe member 13 and the center of the tubular member is 2-5 mm, preferably 3.9 mm.

(31) The material of the node member 15 may also be silicone, latex, plastic as PVC, PU, PP, PE, PTFE or other biocompatible materials or compositions thereof. Developing materials such as those having X-ray development lines or barium sulfate may also be further added. In an embodiment of esophageal cancer, the length of the node member 15 may be 1-15 mm, preferably 1-8 mm. In an embodiment of rectal cancer, the length of the node member 15 may be 1-15 mm, preferably 5-15 mm.

(32) In order to achieve complete airtight between the tubular member 11 and the node member 15, between the fluid-flow pipe member 13 and the node member 15, and between the periphery member 14 and the node member 15, so as to allow the periphery member to successfully inflate and deflate, adhesive (not shown in figures) can be used for assistance.

(33) In some embodiments, multiple fluid-flow pipe members 13 may be connected by one single control element (not shown in figures), such as an air inflation apparatus controlled by a computer that is connect to multiple fluid-flow pipe members 13 and independently controls each periphery member 14 connected to the distal end 18 through valve. In an embodiment of esophageal cancer, the periphery member 14 can have a length of 5-20 mm, preferably 16.5 mm, and may expand to a diameter of 30 mm or less. In an embodiment of rectal cancer, the periphery member 14 can have a length of 20-50 mm, preferably 30 mm, and may inflate to a diameter of 50 mm or less.

(34) FIG. 5 is an illustrative diagram of another embodiment of the catheter apparatus 10 of the present application, wherein the lengths of the fluid-flow pipe members 13 are different from each other, so that different fluid-flow pipe members 13 are individually connected to different segments 1a and fill the spaces 1b, allowing each periphery member 14 to inflate and deflate to achieve individual adjustment of the degree of inflation and deflation.

(35) FIGS. 6(a), 6(b), and 6(c) are three-dimensional, front view and side view illustrative diagrams of the node member 15 of the present application, respectively. Refer to FIG. 2 along with 6(a), 6(b) and 6(c), the node member 15 is a hollow column, wherein the hollow space of the hollow column 33 may allow the tubular member 11 to pass along the hollow space of the hollow column 33 through the node member 15. A channel 32 is disposed on the column wall 31 of the node member 15, so that the fluid-flow pipe member 13 may pass through the node member 15. This allows the space 1b formed between the segment 1a between two adjacent node members 15, and the periphery member 14, to be sealed. That also allows the tubular member 11 and the fluid-flow pipe member 13 to pass through the node member 15 while the periphery member 14 is inflated by being filled with fluid.

(36) FIGS. 7(a), 7(b), and 7(c) are three-dimensional, front view and side view illustrative diagrams of the node member 15 with the connecting ring member 41 according to the present application, respectively. FIGS. 8(a), 8(b), and 8(c) are illustrative diagrams of the connecting ring member 41 of the node member connected with the outer ring member 51. In this embodiment, the connecting ring member 41 is a ring-shaped groove which can be combined with the outer ring member 51 of FIG. 8(a), as shown in FIGS. 8(b) and 8(c). In some embodiments, the outer ring member 51 can be rubber band with elastic tightening force, or elastic biocompatible materials, or non-elastic plastic, metal or the like.

(37) FIG. 9 is an illustrative diagram of the node member 15 connecting with the outer ring member 51 and the periphery member 14 in one embodiment. As shown in FIG. 9, the two adjacent node members 15 fix the periphery member 14 by the connecting ring member 41 and the outer ring member 51, and form a space 1b, so that a fluid (not shown in figures) can enter the space 1b and lead to inflation and deflation of the periphery member 14 of the space 1b. In this embodiment, the quantity of the periphery member 14 can be one. Different segments 1a of the periphery member 14 may be inflatable and deflatable individually by pressure segmentation from the outer ring member 51 and the connecting ring member 41 of the node member 15.

(38) In the embodiment of FIGS. 10 (a)-10(c), the node member 15 has a protruding ring member 71. FIGS. 10(a), 10(b), and 10(c) are three-dimensional, front view and side view illustrative diagrams of the node member 15 with the protruding ring member 71 according to the present application, respectively. FIG. 11 is the illustrative diagram of the periphery member 14 connected with the protruding ring member 71, while the node member 15 having protruding ring member 71. The periphery member 14 is connected to the protruding ring member 71 of the two adjacent node members 15, so that the segment 1a, formed between two adjacent node members 15, forms a sealed space 1b, which allows the periphery member 14 to be inflated or deflated due to the filling of the fluid. In this embodiment, the number of periphery members 14 may be multiple, and may be 4 to 16 as required, connected to the segment formed between different two adjacent node members 15, respectively. FIG. 8 is an illustrative diagram of the periphery member 14 wrapped around the segment 1a as a film, wherein the film thickness of the periphery member 14 is 0.1-2 mm preferably. In an embodiment of esophageal cancer, the periphery member 14 can have a length of 5-50 mm, preferably 5-20 mm. In an embodiment of rectal cancer, the periphery member 14 can have a length of 5-50 mm, preferably 20-50 mm.

(39) FIG. 12 is an illustrative diagram of the periphery member 14 of the catheter apparatus 10 according to the present application, which may be inflatable and deflatable because of the presence of the node member 15. In the present application, since the different spaces 1b can be individually controlled in terms of whether be filled with the fluid or not and the amount of each filling, the degree of inflation and deflation of each periphery member 14 can be individually controlled. When the size of tumor growth in different segments is different, according to the actual tumor growth situation in the patient's body cavity, the periphery member 14 may be inflated by being filled with a smaller amount of fluid at a narrowing of the body cavity (due to a larger or more protruding tumor), or the periphery member 14 may be inflated to a larger size by being filled with more fluid when the tumor grows more superficially (the esophageal lumen is less narrow), thereby achieving the purpose of killing the tumor with less radiation dose, thereby reducing side effects. Moreover, when the periphery member 14 is attached to the catheter, due to the design of the node member 15, the periphery member 14 can be accurately joined by using an adhesive (not shown in figures). This improves the problem of the presence of radiation hot spots caused by the unevenness of the balloon inflation easily caused by displacement of the attachment site, when external balloons are added to a catheter in the existing technology.

(40) In the present application, due to the design of the periphery member 14 and the node member 15, the effect of inflation can be achieved by only a small amount of inflation. Therefore, when determining the degree of inflation, a smaller amount of inflation can be selected to improve the problem of the shrunk balloon prior to inflation in the existing technology shown in FIG. 3(b), which needs to be filled with a certain amount of fluid for maintaining the shape of the balloon. In the present application, because of the design of the periphery member 14 and the node member 15, it is not necessary to add an external balloon as in the previous technology, which causes rubbing against the wall of the body cavity and discomfort to the patient or even wall damage when the catheter is inserted into the body cavity. That improves the smoothness during placement of the catheter into the narrow cavity of the patient.

(41) FIG. 13 is an illustrative diagram of the periphery members 14 of the catheter apparatus 10 inflatable and deflatable individually to control the sizes thereby conforming to the tumor tissue 101 according to the present application. After being connected to the after-loading medical instrument 103, the catheter apparatus 10 (some of the components are omitted) can determine the position at which the periphery members 14 need to be inflated and deflated, and the range of inflation and deflation, along the volume of the tumor tissue 101 in the lumen. Then, the radioactive source 12 is placed for brachytherapy. Since the periphery members 14 of the catheter apparatus 10 of the present application can be individually inflated and deflated, the catheter apparatus 10 can conform to the shape of the tumor tissue 101. When arranging the treatment plan for the patient, the irradiation area of the tumor tissue 101 may be increased and the irradiation dosage of the normal tissue 102 may be decreased. That increases the cure rate of the patient and reduces side effects.

(42) The position at which the periphery member 14 is inflated and deflated, and the range of the inflation and deflation are determined according to the image taken by the tumor imaging instrument 104. The tumor imaging instrument 104 includes X-ray imaging, fluoroscopy (fluoroscope), computed tomography scan (CT Scan), positron tomography (PET), single photon emission tomography (SPECT), nuclear magnetic resonance imaging (MRI), and the like.

(43) In the past, image positioning used a 2D planar system, taking two images being the front and the side, causing the possibility of the presence of spatial errors. Currently, there has been a tendency to use stereotactic orientation of computed tomography. At this time, the fixation effect of the catheter apparatus 10 in the lumen is very important. Since the catheter apparatus 10 conforms to the shape of the tumor tissue 101, the catheter apparatus 10 and the tumor tissue 101 have an effect of closely fitting to each other, and have a good fixation effect, allowing the treatment plan to be more precise. This successfully solves the problems of lowered accuracy of treatment plan caused by the movement of the catheter apparatus 10 due to the patient's breath or the movement during the processes of tumor imaging and the placement of the radiation source.

(44) In summary, compared with the known technology, for example, Bonvoisin-Gerard Esophageal Applicator and Standard Nasopharyngeal Applicator Set of Elekta, and the catheters disclosed in U.S. Pat. Nos. 7,384,411B1, 6,575,932B1, Chinese Patent Publication No. 202387089U, U.S. Pat. Nos. 6,527,692 B1 and 5,910,101, etc., the present application increases the fixation effect, reduces the radiation area of normal tissues, and reduces side effects. At the same time, since the periphery member 14 is segmented by the outer ring member 51 and the connecting ring member 41 of the node member 15, or is segmented in a manner of multiple periphery members 14, Different segments 1a of the periphery member 14 can be inflated and deflated individually, for example having 4-16 individually inflatable and deflatable periphery members 14. In the case of multiple tumors or diffuse tumors, the present application can be fixed wherever necessary, and relies solely on moving the radioactive source to treat multiple diffuse cancer areas without repeated operations, consuming a large amount of time or exhausting the patient. Since the degree of inflation and deflation and the size of the periphery member 14 can be individually controlled, the degree of inflation and deflation and the size of each periphery member 14 can be determined according to the tumor condition during use, thereby fixing according to the shape of the entire segment of the tumor. Thus, even if displacement occurs when the patient breathes or moves, the catheter apparatus 10 has already been conformed to and fixed the tumor, and can move along with the tumor tissue without sliding. This will not lead to change of position relative to the tumor tissue and increases the accuracy of the physician's treatment plan.

(45) The technical features of the present invention can be utilized in any catheter treatment which needs to keep the body cavity open. Hereinafter, the treatment of esophageal cancer and rectal cancer will be exemplified, and the application steps will be described to assist a person having ordinary skill in the art to understand the possible application of the present invention. The invention may be applied in place of other steps of use without departing from the scope of the present application:

(46) Esophageal Cancer:

(47) The catheter apparatus 10 is placed into the esophagus from the nasal cavity. In the state in which the periphery member 14 has not been inflated and deflated, the catheter apparatus 10 can be smoothly placed into the esophagus from the nasal cavity without interference from the external balloon, so that it is not necessary to be placed from the oral cavity. After the catheter apparatus 10 is placed in the esophagus, it is fixed to the outside of the nostrils by adhesion with a tape.

(48) A lumen cath (not shown) is placed in the tubular member 11 of the catheter apparatus 10 until the end, and the lumen cath (not shown) is fixed to the tubular member 11 by adhesion with a tape.

(49) The open end of the lumen cath (not shown) is then connected to the after-loading treatment instrument 103 and a simulated radioactive source that can measure the relative depth of the lumen and develop a CT image is placed therein.

(50) The scout view image (reconstructed planar image) of that portion of the patient is obtained, the distribution area of the simulated source is observed, and the tumor area of the computerized tomographic reconstructed planar image of the treatment planning system is compared to determine the position and degree of inflation of the periphery member 14 which inflates relative to the catheter apparatus 10. Because the catheter apparatus 10 of the present application has a sufficient number of periphery members 14 (e.g. 8 inflatable and deflatable periphery members), even if it is a diffuse tumor, no movement is required after the catheter apparatus is placed, which makes the patient comfortable without anesthesia.

(51) After inflating some of the periphery members 14, the computer tomographic image is scanned to confirm that the inflated size is appropriate. If necessary, the size is adjusted and a computerized tomographic image is rescanned after modification.

(52) The computed tomography image is transmitted to the treatment planning system, depicting the location and area of the tumor when the periphery member 14 is inflated, as well as depicting the surrounding normal tissue (e.g. lung, heart, spinal cord, etc.).

(53) A 3D treatment plan (dose calculation) is made for the patient's various tumor size and shape to ensure that the tumor area is adequately dosed and that the receiving dose of the normal tissue is within a safe range.

(54) The treatment is performed and the irradiation is administrated.

(55) Rectal Cancer:

(56) The catheter apparatus 10 is placed from the anus of the patient to the rectum, and the catheter apparatus 10 is fixed to the outside of the anus by adhesion with a tape.

(57) A lumen cath (not shown) is placed in the tubular member 11 of the catheter apparatus 10 until the end, and a lumen cath (not shown) is fixed to the tubular member 11 by adhesion with a tape.

(58) The open end of the lumen cath (not shown) is then connected to the after-loading treatment instrument 103 and a simulated radioactive source that can measure the relative depth of the lumen and can develop a CT image is placed therein.

(59) The scout view image (reconstructed planar image) of that portion of the patient is obtained, the distribution area of the simulated source is observed, and the tumor area of the computerized tomographic reconstructed planar image of the treatment planning system is compared to determine the position and degree of inflation of the periphery member 14 which inflates relative to the catheter apparatus 10. Because the catheter apparatus 10 of the present application has a sufficient number of periphery members 14 (e.g. 8 inflatable and deflatable periphery members), even if it is a diffuse tumor, no movement is required after the catheter apparatus is placed, which makes the patient comfortable without anesthesia.

(60) After inflating some of the periphery members 14, the computer tomographic image is scanned to confirm that the inflated size is appropriate. If necessary, the size is adjusted and the computerized tomographic image is rescanned after modification.

(61) The computed tomography image is transmitted to the treatment planning system, depicting the location and area of the tumor when the periphery member 14 is inflated, as well as depicting the surrounding normal tissue (e.g. uterus and ovaries in female; prostate, bladder, etc. in male).

(62) A 3D treatment plan (dose calculation) is made for the patient's various tumor size and shape to ensure that the tumor area is adequately dosed and that the receiving dose of the normal tissue is within a safe range.

(63) The treatment is performed and the irradiation is administered.

(64) The present invention does not require the aid of the guide wire, can irradiate the entire diffuse tumor in one brachytherapy without placing the catheter and the radioactive source repeatedly, and can avoid changes of the relative position between the catheter and the tumor that is caused by the breathing or movement of the patient which affects the accuracy of the treatment plan. The present application does not need to be placed from the oral cavity for the treatment of esophageal cancer, and it is not necessary to administer anesthesia to the patient. In addition, instead of an external balloon, inflatable and deflatable components such as the periphery member 14 and the node member 15 are provided to achieve the therapeutic purposes. There is no external balloon that generally rubs against the body cavity wall when it entering the body cavity which causes discomfort to the patient or even wall damage. It greatly improves the smoothness when being placed into a narrow cavity of the patient, solving the problems of the existing technology and achieves a better effect.

SYMBOL DESCRIPTION

(65) Catheter apparatus 10 Tubular member 11 Radioactive source 12 Fluid-flow pipe member 13 Periphery member 14 Node member 15 Control element 16 Opening 17 Distal end 18 Proximal end 19 Segment 1a Space 1b Column wall 31 Channel 32 Hollow space of the hollow column 33 Connecting ring member 41 Outer ring member 51 Protruding ring member 71 Tumor tissue 101 Normal tissue 102 After-loading treatment instrument 103 Tumor imaging instrument 104 Gross tumor volume GTV Clinical target volume CTV Internal target volume ITV Planning target volume PTV