Radiation Therapy Applicators

Abstract

An applicator for delivering radiotherapy seeds to a tumor in a patient through an elongated needle (104). The elongated needle has a needle handle (204) and a needle tube having a predetermined length for insertion into the patient. The applicator has an elongated applicator tube (106) designed to pass through the elongated needle and defining an internal channel for receiving one or more radiotherapy seeds (110), an applicator handle (210) configured to be attached to the needle handle (204), and a stylet (108) within the elongated applicator tube. The elongated applicator tube is longer than the elongated needle.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 63 / 159,499, filed March 11, 2021, which is incorporated herein by reference.

[0002] The present invention relates generally to radiation therapy, and more particularly to a method for implanting a radiation therapy source in a tumor located in an internal organ. [Background technology]

[0003] Alpha particle emitters are a powerful tool in radiation therapy for certain types of tumors, including malignant tumors. Proper delivery of the seeds incorporating the alpha particle emitters is critical to successful treatment. Delivery should place the seeds precisely within the tumor without prematurely exposing the patient's tissues to radioactive or other unhealthy materials.

[0004] One type of alpha therapy source is a diffusing alpha-emitter radiation therapy (DaRT) source loaded with radium-223 or radium-224 atoms, which have half-lives that are neither too long nor too short for therapeutic purposes.

[0005] Kelson, US Pat. No. 8,834,837, describes a method for DaRT treatment.

[0006] PCT Publication WO 2015 / 136192, entitled "Brachytherapy Apparatus and Related Treatment Methods," describes the delivery of a container of radioactive material through a needle inserted into a channel of an endoscope.

[0007] Wang, US Pat. No. 4,532,935, describes a bronchoscope needle that includes an outer catheter, a needle attached to an inner catheter inside the outer catheter, and a stylet passing through the needle. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Patent No. 8,834,837 [Patent Document 2] WO2015 / 136192 publication [Patent Document 3] U.S. Patent No. 4,532,935 Summary of the Invention [Means for solving the problem]

[0009] According to an embodiment of the present invention, there is provided herein an applicator for delivering radiotherapy seeds to a tumor in a patient through an elongated needle having a needle handle and a needle tube having a predetermined length for insertion into the patient; The applicator is an elongated applicator tube designed to pass through an elongated needle, the elongated applicator tube defining an internal channel for receiving one or more radiotherapy seeds; an applicator handle configured to be attached to the needle handle; a stylet within an elongated applicator tube; having The elongated applicator tube is longer than the elongated needle.

[0010] Optionally, the elongated applicator tube has a flexibility that is not suitable for insertion into a patient, but can pass through an internal channel of the elongated needle when the elongated needle is in the patient. Optionally, the elongated applicator tube has a length such that a distal end of the elongated applicator tube is proximate a distal end of the elongated needle when the applicator handle is attached to the needle handle. Optionally, the elongated applicator tube has a length of at least 20 centimeters. Optionally, the applicator further comprises a seed dispensing unit configured to grip the applicator handle and a handle of the stylet in a manner that allows movement of the applicator handle relative to the stylet handle such that the stylet expels a seed from the distal end of the elongated applicator tube. Optionally, the seed dispensing unit comprises a casing configured to grip the stylet handle, and a slidable holder coupled to the applicator handle and configured to slide relative to the casing.

[0011] Optionally, the seed distribution unit has a guide handle that moves the applicator handle relative to the stylet handle when moved along the axis of the elongated applicator tube by a user. Optionally, the seed distribution unit is configured to limit movement of the guide handle along the axis of the elongated applicator tube in one stroke to the length of a single seed. Optionally, the seed distribution unit is configured to require lateral movement of the guide handle to allow further movement of the guide handle along the axis of the elongated applicator tube after movement of the length of a single seed. Optionally, the seed distribution unit is configured to retract the applicator handle while the handle of the stylet is held in place. Optionally, the elongated applicator tube has a length of at least 50 centimeters.

[0012] There is further provided, in accordance with an embodiment of the present invention, a seed distribution unit comprising: an applicator handle holder configured to grasp an elongated applicator handle including a plurality of radiotherapy seeds at a distal end thereof; a stylet handle grasper configured to grasp a handle of a stylet within the elongate applicator; a casing configured to permit movement of the applicator handle holder relative to the stylet handle grasper such that the stylet expels a seed from a distal end of the elongate applicator; having The casing is configured to limit continued movement of the applicator handle holder relative to the stylet handle grasper to the length of a single seed, such that further movement is permitted only after an adjusting action by a human user.

[0013] Optionally, the applicator handle holder has a guide handle that is used by a user to move the applicator handle holder in a first direction relative to the stylet handle grasper, and the casing requires movement in a second direction different from the first direction to move in the first direction beyond the length of a single seed. Optionally, the second direction is perpendicular to the first direction. Optionally, the applicator handle holder has a ratchet that prevents rearward movement of the applicator handle holder after it has moved the length of a seed unless a ratchet release button is pressed. Optionally, the casing has one or more ball plungers that limit continued movement of the applicator handle holder relative to the stylet handle grasper to the length of a single seed.

[0014] Further, in accordance with an embodiment of the present invention, there is provided a system for delivering radiotherapy seeds to a tumor, the system including an endoscope defining an elongated channel, an elongated needle passing through the elongated channel of the endoscope, an elongated applicator passing through the elongated needle and defining an internal channel for receiving one or more radiotherapy seeds, and a stylet within the elongated applicator.

[0015] Optionally, the system has a seed distribution unit configured to receive a needle handle at one end and a stylet handle at an other end. Optionally, the seed distribution unit includes a needle handle holder configured to hold the needle handle and a proximal compartment to receive the stylet handle. Optionally, the seed distribution unit is configured to push the needle handle holder toward the proximal compartment a fixed length sufficient to dispense a single seed from the applicator.

[0016] Further, in accordance with an embodiment of the present invention, there is provided a method of delivering radiotherapy seeds to an internal organ of a patient, the method comprising: providing an elongated applicator of sufficient length to extend from outside a patient to an internal organ, the elongated applicator including one or more radiotherapy seeds at a distal end thereof and including a stylet extending through the elongated applicator from a proximal end thereof to the one or more radiotherapy seeds; Inserting an elongate applicator into the elongate needle; piercing the organ with a long thin needle; dispensing at least one of the seeds into the patient by retracting the elongate needle and the elongate applicator relative to the stylet; has.

[0017] Optionally, the step of inserting the elongate applicator into the elongate needle is performed while the elongate needle extends from outside the patient to the internal organ. Optionally, the step of inserting the elongate applicator into the elongate needle is performed while the elongate needle is entirely outside the patient. Optionally, the method includes directing the needle through an endoscope into the vicinity of the internal organ. Optionally, the method includes connecting a handle of the needle to a handle of the applicator prior to dispensing at least one of the seeds. [Brief description of the drawings]

[0018] [Figure 1]1 is a partial cross-sectional view of a system for delivering radiotherapy seeds, according to an embodiment of the present invention. [Diagram 2] 1 is a schematic diagram of a proximal end of a needle in a seed distribution unit according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a schematic diagram of the seed distribution unit of FIG. 2 without a needle handle, according to an embodiment of the present invention. [Figure 4] FIG. 1 is a schematic diagram of a cradle needle holder that holds a needle handle, according to an embodiment of the present invention. [Diagram 5] FIG. 13 is a schematic diagram of an upside-down cradle needle holder with a guide used to move the needle holder, according to an embodiment of the present invention. [Figure 6] 1 is a schematic diagram of the back side of the casing of a seed distribution unit, in addition to a guide handle, according to an embodiment of the present invention. [Figure 7] 2 is a schematic diagram of a slide frame and corresponding guide according to an embodiment of the present invention. [Figure 8A] FIG. 2 is a schematic diagram of a ratchet mechanism according to an embodiment of the present invention. [Figure 8B] FIG. 2 is a schematic diagram of a ratchet mechanism according to an embodiment of the present invention. [Figure 9] 1 is a flowchart of operations performed when implanting radiation therapy seeds into a patient's tumor, in accordance with an embodiment of the present invention. [Figure 10A] 1 is a schematic diagram of an applicator kit according to an embodiment of the present invention. [Figure 10B] FIG. 10B is a schematic diagram of the proximal end of the applicator kit of FIG. 10A with the first fixation element removed, in accordance with an embodiment of the present invention. [Figure 11A] 1 is a schematic top view of a seed distribution unit according to an embodiment of the present invention. [Figure 11B] FIG. 11B is a schematic side view of the seed distribution unit of FIG. 11A with a needle handle and a sheath handle mounted therein. [Figure 12A] FIG. 11B is a side view of the seed distribution unit of FIG. 11A with a stylet carrier mounted therein, in accordance with an embodiment of the present invention. [Figure 12B] FIG. 11B is a top view of the seed distribution unit of FIG. 11A with a stylet carrier mounted therein, in accordance with an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] One aspect of some embodiments of the present invention relates to the delivery of radiotherapy seeds to a patient's internal organs in three tubes, each of which is separately operable, one within the other. Delivering radiotherapy seeds in three tubes increases the flexibility of the delivery. In some embodiments, the outer tube is an endoscope, the middle tube is an elongated needle, and the inner tube is an applicator that carries the seeds. Using an elongated needle in addition to an endoscope allows the endoscope to take advantage of its properties of robustness and visibility to reach the vicinity of the tumor, while allowing the elongated needle to take advantage of its additional flexibility and small diameter to reach the tumor itself. Using an elongated applicator separate from the elongated needle to carry the seeds allows the seeds to be delivered to the distal end of the elongated needle in such a way that the seeds rub against the inner wall of the elongated needle while the elongated needle is in the patient, without passing the seeds through the internal channel of the elongated needle. Some radiotherapy seeds have active radioactive particles on their outer surface, so that passing the seeds through the inner channel of the elongated needle can result in a significant portion of the seed's activity being lost due to the seeds rubbing against the inner walls of the elongated needle. By separately inserting an elongated applicator, additional seeds can be delivered to the tumor beyond those originally loaded onto the elongated needle. Additionally, the use of an elongated applicator allows the distal end of the elongated needle to be delivered to the tumor without seeds therein, allowing for additional flexibility of the elongated needle if needed.

[0020] An aspect of some embodiments of the invention relates to a system for delivering seeds to an internal organ of a patient, comprising two elongated tubes of approximately the same length, one nested within the other. Optionally, each of the elongated tubes has a handle configured to be coupled together such that the distal ends of the elongated tubes are proximate to each other when the handles are coupled. In some embodiments, the inner tube carries one or more radiotherapy seeds and a stylet that is used to push the seeds out of the distal end of the applicator.

[0021] FIG 1 is a partial cross-sectional view of a system 100 for delivering one or more radiotherapy seeds 110, according to an embodiment of the present invention. The system 100 has an endoscope 102 suitable for insertion into a patient. An elongated needle 104 having a sharp edge 114 (shown diagrammatically in FIG 1) such as those used in the art for taking biopsies is inserted through a channel of the endoscope 102. The elongated needle 104 optionally includes an outer sheath 118 in which the elongated needle 104 can slide between a delivery state in which the sharp edge 114 is entirely within the sheath 118, and an actuated state in which the sharp edge 114 is outside the sheath, as shown in FIG 1.

[0022] An applicator 106 (carrying the seeds 100 therein) passes through the needle 104. A stylet 108 within the applicator 106 is used to push the seeds 110 into the patient. As shown, the applicator 106 carries five seeds 110, each having an overall length of 0.5 to 2 centimeters. However, the applicator 106 may carry less than five or less than three seeds 110, or may carry more than five or more than ten seeds 110.

[0023] Although the needle 104 is shown within a channel of the endoscope 102, in some cases the needle 104 may extend beyond the distal end of the endoscope and enter into areas of the endoscope 102 that are too narrow or inaccessible. Thus, generally, at least a distal portion of the elongated needle 104 is sufficiently rigid to be independently maneuverable within a patient, while being flexible enough to be maneuvered through tortuous and narrow body channels. In some embodiments, the elongated needle 104 has an outer diameter of less than 1.7 millimeters, less than 1.2 millimeters, or less than 1 millimeter, e.g., 0.8 millimeters, and an inner diameter of less than 1.25 millimeters, less than 1 millimeter, less than 0.8 millimeters, or less than 0.6 millimeters, e.g., 0.45 millimeters. Alternatively or in addition, the elongated needle 104 has a relatively large outer diameter, e.g., greater than 1 millimeter, greater than 1.2 millimeters, or greater than 1.5 millimeters.

[0024] In order to fit into the elongated needle 104, the applicator 106 has an outer diameter equal to or smaller than the inner diameter of the elongated needle 104. The inner diameter of the applicator 106 is large enough to hold a seed 110 having a diameter optionally greater than 0.3 millimeters, such as 0.37 millimeters. The walls of the applicator 106 optionally have a thickness of less than 0.2 millimeters, less than 0.15 millimeters, or less than 0.1 millimeters. Since the applicator 106 is intended to pass through the inner channel of the needle 104, in some embodiments the applicator 106 is very soft and not suitable for passing through a patient by itself. Furthermore, the applicator 106 is optionally highly flexible, so that once placed in the needle 104, the combined flexibility of the needle 104 and the applicator 106 allows them to be manipulated within the patient. Alternatively or additionally, if complex manipulations need to be performed, the applicator 106 can be removed from the needle 104 and replaced once the needle is properly positioned. In some embodiments, the applicator 106 comprises a braided or non-braided composite polyimide tube, and the applicator 106 may be removed from the needle 104 to refill its distal end with seeds 110, and then reinserted into the needle 104 after refilling with seeds. The elongated tube of the applicator 106 is configured to be sufficiently rigid to allow for removal and reinsertion.

[0025] In some embodiments, the length of the applicator 106 is the same as the length of the elongated needle 104 (e.g., by no more than 20 millimeters or no more than 10 millimeters), such that when the applicator 106 is inserted into the internal channel of the needle 104 and their handles are connected, the distal end of the applicator 106 coincides (within 10 millimeters or within 5 millimeters) with the distal end of the needle 104. In some embodiments, the applicator 106 is longer than the needle 104 by the length of the needle 104 handle (within 5 millimeters).

[0026] In other embodiments, the applicator 106 is longer than the elongated needle 104 such that when the handle of the elongated needle 104 is connected, the applicator 106 extends beyond the end of the needle 104 by at least 2 centimeters, at least 5 centimeters, or at least 8 centimeters. Optionally, the distal end of the applicator 106 has a hard material such as Nitinol that allows a sharp needle to be used to penetrate the tumor. Inserting the applicator 106 itself into the tumor has the advantage of a smaller diameter entry hole. In some embodiments, the distal end of the applicator 106 is pre-shaped at a specific angle to reach specific locations and / or directions that are difficult to access with a needle.

[0027] The elongated tube of the needle 104 and applicator 106 has a length of at least 20 centimeters, at least 50 centimeters, at least 80 centimeters, at least 100 centimeters, at least 120 centimeters, or at least 150 centimeters. The stylet 108 is generally slightly longer than the applicator 106 so that it can push all of the seeds 110 out of the distal end of the applicator.

[0028] 2 is a schematic diagram of the proximal end of a needle 104 in a seed distribution unit 200, according to an embodiment of the present invention. The seed distribution unit 200 is designed to allow a human user to controllably move the needle 104 and applicator 106 relative to the stylet 108 to dispense a seed 110. As described in more detail below, the seed distribution unit 200 includes a casing 201 that receives a needle handle 204 along with a sheath handle 218 on one end and a stylet handle 228 on the other end such that a user can controllably push the handles relative to one another. The seed distribution unit 200 is designed, in some embodiments, to easily retract the needle 104 and applicator 106 relative to the stylet 108 the length of a single seed to expel the seed. In some embodiments, prior to mounting the needle handle 204 to the seed distribution unit 200 , the proximal handle 210 of the applicator 106 is connected to the needle handle 204 , for example, by a swivel Luer lock 212 .

[0029] In some embodiments, at one end, the seed distribution unit 200 includes a lip 202 of a slidable needle holder 252 designed to hold a needle handle 204, and at the other end, the seed distribution unit 200 includes a compartment 218 designed to receive a proximal handle 228 of the stylet 108.

[0030] The seed distribution unit 200 is optionally long enough to accommodate the needle handle 204, the applicator handle 210 and the stylet handle 228 with an open area the length of several (e.g., at least two, at least three, at least four, or at least five) seeds 110 between the applicator handle 210 and the stylet handle 228, so that the needle handle 204 may be retracted with the applicator handle 210 to expel the seeds.

[0031] Applicant has found that expelling the seeds 110 by retraction of the needle 104 and / or applicator 106 has advantages over pushing the seeds forward with the stylet 108. Using expelling by retraction, entry into the tumor is achieved by the distal end of the needle 104 and / or applicator 106, which may be more amenable to manipulation, for example by having a sharper end than the seeds 110. Also, the exact location of the seeds may be determined prior to expelling the seeds, and if necessary, the distal end of the applicator 106 may be repositioned before the seeds are expelled.

[0032] Note that in some embodiments, instead of using retraction, the stylet 108 is pushed forward to expel the seeds 110 from the needle and / or applicator 106 and into the tumor.

[0033] FIG. 2 also shows a ratchet release button 220 that allows for resetting the position of the needle holder 252 (FIG. 3) relative to the seed distribution unit 200, as described below with reference to FIG.

[0034] 3 is a schematic diagram of a seed dispensing unit 200 without a needle handle 204, according to an embodiment of the present invention. The seed dispensing unit 200 optionally includes a needle holder 252, also referred to herein as a cradle, having a lip 202 for gripping the needle handle 204 (FIG. 2). The needle holder 252 is optionally designed to slide relative to the casing 201. Optionally, the needle holder 252 slides within the casing on a slide frame 260 located on the rear wall of the casing 201. The function of the slide frame 260 will be described below with reference to FIG. 7.

[0035] See also FIG. 4, which is a schematic diagram of a cradle needle holder 252 holding a needle handle 204 without a casing 201, according to an embodiment of the present invention. In some embodiments, the cradle needle holder 252 is designed to hold a needle handle 204 of a particular size and shape. In other embodiments, the cradle needle holder 252 can accommodate needle handles of multiple different lengths, for example, by the cradle needle holder 252 having a wall 254 on its long axis only at its distal end and not at its proximal end. Alternatively or additionally, the cradle needle holder 252 can accommodate needle handles of multiple different widths and / or shapes, for example, by elasticity of the lips 202 and / or adjustability of the distance between the lips 202 while still attached to the cradle needle holder 252. Alternatively or in addition, the casing 201 replaceably receives a cradle needle holder 252, and if a non-standard needle handle 204 is used, the needle handle is provided with a replacement cradle needle holder 252 that properly grips the non-standard needle handle 204.

[0036] 5 is an upside-down schematic diagram of a cradle needle holder 252 with a guide 256 used to move the needle holder, according to an embodiment of the present invention. The guide 256 has a guide handle 266 located on the rear exterior side of the casing 201 and a guide base 262 connected to the needle holder 252. A T-shaped rod 258 is optionally rotatably connected to both the guide handle 266 and the guide base 262 in a manner that allows limited rotation of the rod while connecting the guide handle 266 to the guide base 262, as described in more detail below.

[0037] FIG. 6 is a schematic diagram of the back side of casing 201 along with guide handle 266, in accordance with an embodiment of the present invention.

[0038] The guide handle 266 can be moved by an operator, such as a physician, to expel the seeds 110 (FIG. 1). In some embodiments, the casing 201 has a slot 238 on its back side to allow sliding of the rod 258 (FIG. 5).

[0039] 7 is a schematic diagram of a slide frame 260 and guide 256 according to an embodiment of the present invention. Slide frame 260 has a central slot 272 that corresponds to slot 238 in casing 201 (FIG. 6) and allows guide 256 to slide along the casing, thereby moving needle holder 252 rearwardly to expel seeds from the distal end of elongate needle 104.

[0040] In some embodiments, the slide frame 260 further defines side slots 274 (labeled 274A, 274B, 274C, 274D) on either side of the central slot 272. Each side slot 274 optionally has the length of one seed. The side slots 274 are alternately distributed along the length of the central slot 272 with a slight overlap of about the width of the T-shaped rod 258. As shown, the side slots 274 are only partially formed in the slide frame 260. In other embodiments, the side slots 274 are formed throughout the entire thickness of the slide frame 260. Instead of the side slots 274 having the length of one seed, one or more of the slots, and possibly all of the slots, have the length of multiple seeds, for example the length of two seeds. In one embodiment, the first side slot 274A has a double length to release two seeds, and the remaining slots are designed to release one seed. Further alternatively, some or all of the slots 274 have a length less than the length of the seed 110 and are retracted a multiple (eg, two or three) slot lengths to release the seed needle holder 252.

[0041] The guide 256 is designed such that the T-shaped head of the T-shaped rod 258 does not fit into the central slot 272, but one of the ends of the T-shaped head must enter one of the side slots 274. Thus, in order to slide along the slide frame 260, the end of the T-shaped rod 258 must be located in the slidable side slot 274. Initially, the end of the T-shaped rod 258 is placed in the side slot 274A. In this position, the guide 256 can slide the length of a single seed 110, so that the seed can be released. The guide handle 266 is then optionally pushed in a direction perpendicular to the sliding direction so that the end of the T-shaped rod 258 enters the side slot 274B. In this state, the guide 256 can slide the length of another seed 110. The guide handle 266 is then pushed in a direction perpendicular to the sliding direction in the opposite direction to that previously pushed, so that the end of the T-shaped rod 258 enters the side slot 274C. This process may continue to release any number of seeds 110 from within the applicator 106.

[0042] It should be noted that although the above embodiment describes a particular mechanism for limiting the sliding of the needle holder 252, other suitable mechanisms for sliding in stages along the length of the seed 110, such as a ball plunger, may be used, as described below with reference to Figures 10A-12B.

[0043] FIG. 8A is a schematic diagram of a ratchet mechanism 280 within a casing 201, in accordance with an embodiment of the present invention.

[0044] FIG. 8B is a schematic diagram of the interaction of ratchet mechanism 280 and needle holder 252, in accordance with an embodiment of the present invention.

[0045] Optionally, a ratchet mechanism 280 limits the movement of the cradle needle holder 252. Optionally, the needle holder 252 defines a hole 282 along its length, and the ratchet mechanism 280 includes a member 284 having a bulging head 285 configured to fit into the hole 282. In some embodiments, a spring biases the bulging head 285 against the back of the cradle needle holder 252 when the bulging head 285 is over the hole 282, such that the bulging head 285 fits into the hole and prevents or limits movement of the needle holder 252. To release the bulging head 285, a user can press the ratchet release button 220. The hole 282 is optionally formed at a location corresponding to the end of the side slot 274, such that once the needle holder 252 has been moved the length of the needle, the needle holder 252 cannot move back unless the user presses the button 220. To release another seed, the user moves the guide 256 sideways in a manner that allows further movement and prevents rearward movement through the current side slot 274. The user then presses the button 220 to remove the bulging head 285 from the hole 282 in which it was located to allow further movement.

[0046] In some embodiments, the engagement of bulging head 285 in hole 282 prevents both forward and backward movement, and movement is only possible by pressing button 220. Alternatively, the engagement of bulging head 285 in hole 282 prevents backward movement, but forward movement is permitted by hole 282 having, for example, a forward slope that allows exit of bulging head 285 with forward movement.

[0047] FIG. 9 is a flowchart of operations performed using system 100 to implant radiation therapy seeds 110 in a patient's tumor, according to an embodiment of the present invention.

[0048] 9 optionally begins with the insertion of an endoscope 102 into a patient (302). In some embodiments, a radial ultrasound is also inserted into the patient to identify the location of a tumor and direct the distal end of the bronchoscope 102 to the tumor (304). Alternatively or additionally, any other method, such as fluoroscopy, may be used to direct the endoscope 102 to the tumor (306).

[0049] In some embodiments, the needle 104 is inserted into the endoscope 102 before the applicator 106 is inserted into the needle 104. In these embodiments, the needle 104 is inserted into the proximal end of the endoscope 102 and guided (310) through the endoscope to its distal end. Optionally, the needle 104 is inserted into the proximal end of the endoscope 102 from the seed distribution unit 200. After the location of the needle 104 is confirmed (312), the applicator 106 is inserted into the proximal end of the needle outside the patient and guided to the tip of the needle 104. The needle then pierces tissue (330) and the applicator 106 inserts seeds into the tumor under the control of a user operating the seed distribution unit 200.

[0050] In another embodiment, the needle 104 is inserted (324) into the patient with the applicator 106 pre-attached. The needle 104 is attached (328) to the seed distribution unit 200 with the applicator 106 already in it, and the needle and applicator together are guided (320) through the endoscope 102 to the tumor. The position of the needle 104 relative to the tumor is confirmed (322), and then the needle pierces the tissue (330) and the seeds are inserted into the tumor by pushing the stylet 108 out of the seed distribution unit 200.

[0051] 9 do not necessarily have to be performed in the order shown and / or described, but may be performed in other orders and / or one or more operations may be performed simultaneously. For example, in some embodiments, the applicator 106 is inserted into the needle 104 only after the needle has punctured the tumor. Imaging to confirm the position of the needle and applicator may be performed whenever deemed necessary, optionally continuously.

[0052] According to the above embodiment, the seeds 110 are delivered to the tumor in four channels. 1) Outer endoscope 102 2) Needle sheath 118 3) Needle 104 4) Applicator 106

[0053] Although the seeds 110 can be delivered through only two channels (e.g., endoscope and needle), the use of an additional channel (e.g., applicator 106) provides additional flexibility to the delivery process. The applicator 106 provides extra protection to the seeds 110, preventing them from rubbing against the inner wall of the needle 104, thereby preventing the radionuclides in the seeds 110 from being rubbed off by friction.

[0054] FIG. 10A is a schematic diagram of an applicator kit 400 according to an embodiment of the present invention.

[0055] FIG. 10B is a schematic diagram of the proximal end of the applicator kit 400 with the first fixation element 410 (FIG. 10A) removed, in accordance with an embodiment of the present invention.

[0056] The applicator kit 400 includes an applicator 106 loaded with one or more radioactive seeds (FIG. 1) near its distal end, and an applicator handle 210 with a swivel luer lock 212 at its proximal end for connecting to a needle handle 204. The applicator kit 400 further includes a stylet 108 within the applicator 106, which has a stylet handle 420 attached to a stylet carrier 428. Optionally, the stylet carrier has a ball plunger 402 at its base for locking the stylet in a desired position within a casing 454, as described below. In addition, the kit 400 includes a first fixation element 410 and a second fixation element 412. As described above, the applicator 106 is designed to be delivered with an elongated needle 104 (FIG. 1). The elongated needle 104 may be supplied with the applicator kit 400 or may be provided separately.

[0057] FIG. 11A is a schematic top view of a seed distribution unit 450 according to an embodiment of the present invention.

[0058] 11B is a schematic side view of the seed distribution unit 450 of FIG. 11A with the needle handle 204 and the sheath handle 218 mounted therein. The seed distribution unit 450 has a casing 454 designed to receive the sheath handle 218 at one end and the stylet carrier 428 (FIG. 10A) at the other end. Unlike the seed distribution unit 200, which receives the stylet handle 228 (FIG. 2) in a fixed position, the casing 454 is designed to allow the stylet carrier 428 to slide within the casing. The seed distribution unit 450 further includes a slider 452 designed to receive the needle handle 204 and slide along the casing 454 together with it. A slide gripper 456 is used by a physician or other medical professional to slide the slider 452. In some embodiments, the casing 454 has one or more ball plungers 460 on its sidewall and the slider 452 has one or more corresponding notches designed to stop the slide at a predetermined distance, e.g., the size of a single seed. A notch 458 is formed in the bottom of the casing 454 into which the ball plunger 402 fits to lock the stylet carrier 428, as described below.

[0059] 12A and 12B are side and top views, respectively, of a casing 454 with a stylet carrier 428 mounted therein, according to an embodiment of the present invention.

[0060] In operation, according to some embodiments, the applicator 106 is mounted within the elongated needle 104 and the applicator handle 210 is mounted to the needle handle 204. The sheath handle 218 is placed on one side of the casing 454, the needle handle 204 is mounted within the slider 452, and the stylet carrier 428 is slid on the other side of the casing 454. In this state, with the first fixation element 410 and the second fixation element 412 placed in position between the applicator handle 210 and the stylet handle 420, the distal tip of the elongated needle 104 is brought into proximity with the tumor in which the seed 110 is to be implanted. Typically, the sharp end of the elongated needle 104 is retracted into the sheath 118 such that there is a gap between the sheath handle 218 and the needle handle 204 during delivery of the tip of the elongated needle 104 to the tumor.

[0061] In preparation for implanting the seeds 110, the first fixation element 410 is removed from the casing 454. To push the needle 104 into the tumor, the sliding gripper 456 slides distally together with the slider 452, thereby moving the needle handle 204, the applicator handle 210, and the stylet carrier 428 together with the stylet handle 420 towards the sheath handle 218. After a penetration distance appropriate for a predetermined number of seeds, the ball plunger 402 at the bottom of the stylet carrier 428 locks into a notch 458, preventing the stylet carrier 428 from moving. To expel the seeds, the sliding gripper 456 slides proximally, thereby pulling the needle 104 and applicator 106 distally, but the stylet 108 does not move because the stylet carrier 428 is locked in place. Thus, the stylet 108 prevents the seeds from retracting with the needle 104 and the seeds remain within the tumor.

[0062] Optionally, as the slide gripper 456 is retracted, the sidewall ball plunger 460 engages a corresponding notch after retraction of each seed length, indicating to the operator that the seed has been released. After a predetermined number of seeds have been released, the second fixation element 412 may be removed to allow the stylet handle 420 to slide distally on the stylet carrier 428 to push additional seeds distally within the applicator 106. The distal end of the sheath 118 is then positioned in an appropriate position relative to the tumor (either the same tumor or a different tumor), and the needle 104 is inserted into the tumor and retracted repeatedly to implant additional seeds.

[0063] In some embodiments, the predetermined number of seeds that may be implanted following removal of each of the first and second fixation elements 410 and 412 is two. However, in other embodiments, the predetermined number of seeds is greater than two, such as three or four. Alternatively, the predetermined number of seeds is one. In the above description, the applicator kit 400 includes only two fixation elements 410 and 412, but in other embodiments, the applicator kit includes additional fixation elements such that more seeds may be implanted using the applicator kit.

[0064] The endoscope 102 may be any suitable type of endoscope, including a bronchoscope, an anoscope, an arthroscope, a colonoscope, a colposcope, a cystoscope, an esophagoscope, a gastroscope, a laparoscope, a laryngoscope, a neuroendoscope, a rectoscope, a sigmoidoscope, or a thoracoscope. Although the above description is specifically directed to an endoscope, in some embodiments of the invention, the needle 104 carrying one or more seeds 110 and the applicator 106 are inserted into the patient through other types of medical probes, which may or may not include a viewing device. In still other embodiments, the needle 104 is inserted directly into the patient without the use of a primary endoscope or medical probe.

[0065] Conclusion It will be understood that the methods and apparatus described above should be construed as including apparatus for performing the methods and methods of using the apparatus. It should be understood that features and / or steps described with respect to one embodiment may be used with other embodiments, and that not all embodiments of the invention will have all of the features and / or steps shown in a particular figure or described with respect to one of the particular embodiments. Tasks are not necessarily performed in the exact order described.

[0066] It should be noted that some of the above embodiments may include details of structures, operations, or structures and operations that are not considered essential to the present invention, but are described as examples. The structures and operations described herein may be replaced with equivalents that perform the same function even if the structures or operations are different, as is known in the art. The above-described embodiments are given by way of example, and the present invention is not limited to those specifically shown and described above. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described above, as well as variations and modifications thereof that would occur to a person skilled in the art upon reading the above description and that are not disclosed in the prior art. Thus, the scope of the present invention is limited only by the elements and limitations used in the claims, and the terms "comprise", "include", "have" and their conjugations mean "including, but not necessarily limited to", when used in the claims. [Explanation of symbols]

[0067] 100 Systems 102 Endoscope 104 needles 106 Applicator 108 Stylet 110 Radiation Therapy Seed 200 Seed Distribution Units

Claims

1. 1. An applicator for delivering radiotherapy seeds to a tumor in a patient through an elongated needle, the elongated needle having a needle handle and a needle tube having a predetermined length for insertion into the patient; The applicator comprises: an elongated applicator tube designed to pass through the elongated needle, the elongated applicator tube defining an internal channel for receiving one or more radiotherapy seeds; an applicator handle configured to be attached to the needle handle; a stylet within the elongated applicator tube; having The elongated applicator tube is longer than the elongated needle.

2. 2. The applicator of claim 1, wherein the elongated applicator tube has a flexibility not suitable for insertion into a patient, but is capable of passing through an internal channel of the elongated needle when the elongated needle is within the patient.

3. 2. The applicator of claim 1, wherein the elongated applicator tube has a length such that a distal end of the elongated applicator tube is adjacent to a distal end of the elongated needle when the applicator handle is attached to the needle handle.

4. The applicator of claim 1 , wherein the elongated applicator tube has a length of at least 20 centimeters.

5. 5. The applicator of claim 1, further comprising a seed dispensing unit configured to grasp the applicator handle and a handle of the stylet in a manner that allows movement of the applicator handle relative to the stylet handle such that the stylet expels a seed from a distal end of the elongate applicator tube.

6. The seed distribution unit comprises: a casing configured to grip the stylet handle; a slidable holder coupled to the applicator handle and configured to slide relative to the casing; 6. The applicator of claim 5, comprising:

7. 7. The applicator of claim 6, wherein the seed distribution unit includes a guide handle that moves the applicator handle relative to the stylet handle when moved by a user along the axis of the elongated applicator tube.

8. 8. The applicator of claim 7, wherein the seed dispensing unit is configured to limit movement of the guide handle along the axis of the elongated applicator tube in one stroke to the length of a single seed.

9. 9. The applicator of claim 8, wherein the seed dispensing unit is configured to require lateral movement of the guide handle to allow further movement of the guide handle along the axis of the elongated applicator tube after movement of the length of the single seed.

10. The applicator of claim 5 , wherein the seed dispensing unit is configured to retract the applicator handle while the handle of the stylet is held in place.

11. The applicator of claim 10, wherein the elongated applicator tube has a length of at least 50 centimeters.

12. 1. A system for delivering radiotherapy seeds to a tumor, comprising: An endoscope forming an elongated channel; an elongated needle passing through the elongated channel of the endoscope; an elongate applicator passing through said elongate needle and defining an internal channel for receiving one or more radiotherapy seeds; a stylet within the elongate applicator; and The system has:

13. The system of claim 12 , further comprising a seed dispensing unit configured to receive a handle of the needle at one end and a handle of the stylet at an opposite end.

14. The system of claim 13 , wherein the seed distribution unit includes a needle handle holder configured to hold the needle handle and a proximal compartment that receives the handle of the stylet.

15. 15. The system of claim 14, wherein the seed dispensing unit is configured to push the needle handle holder toward the proximal compartment a fixed length sufficient to dispense a single seed from the applicator.

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