Catheter for detecting radiation

Abstract

A catheter system and a radiotherapy monitoring system, the catheter system for monitoring radiation during radiotherapy, the catheter system comprising: an elongate catheter body configured for placement within a patient; a plurality of radiation response sensing elements disposed at different longitudinal positions along the catheter body; and a signal interface configured to transmit the signal generated by the sensing element to a processing circuit, where the processing circuit is configured to determine information indicative of a location or behavior of the radiotherapy source based on the signal generated by the sensing element. The catheter system and the radiotherapy monitoring system can correctly arrange and locate radiation and avoid too little or too much radiation during therapy.

Description

[0001] This application is a divisional application of Chinese patent application No. 202280030102.0 entitled "Urinary catheter for detecting radiation" (based on international patent application No. PCT / IB2022 / 053685 filed on April 20, 2022, which entered the Chinese national phase on October 20, 2023).

[0002] priority

[0003] This application is a continuation-in-part of U.S. Patent Application No. 16 / 713,530, filed on December 13, 2019. The entire contents of that application are therefore incorporated herein by reference. Background Technology

[0004] The limitations and disadvantages of conventional methods for data storage will become apparent to those skilled in the art by comparing them with some aspects of the methods and systems of the present invention set forth in the remainder of this disclosure with reference to the accompanying drawings. Summary of the Invention

[0005] A urinary catheter is provided for detecting and tracking radiation dose during radiotherapy, the catheter being substantially as shown in at least one figure and / or described in conjunction with at least one figure, as set forth more fully in the claims. Attached Figure Description

[0006] Figure 1 Exemplary interstitial brachytherapy using an afterloader for tumors in a patient's prostate, according to several aspects of this disclosure, is illustrated.

[0007] Figure 2 An exemplary arrangement of a urinary catheter according to several aspects of this disclosure is shown.

[0008] Figure 3A An exemplary urinary catheter for measuring radiation is shown according to several aspects of this disclosure.

[0009] Figure 3B A cross-sectional view of an exemplary urinary catheter for measuring radiation, according to several aspects of this disclosure, is shown.

[0010] Figure 4A An exemplary arrangement of a urinary catheter according to several aspects of this disclosure is shown.

[0011] Figure 4B Another arrangement of an exemplary urinary catheter according to several aspects of this disclosure is shown.

[0012] Figure 5A , Figure 5B and Figure 5C A cross-sectional view of an alternative exemplary urinary catheter for measuring radiation, according to several aspects of this disclosure, is shown. Detailed Implementation

[0013] Brachytherapy is commonly used as an effective treatment for cervical cancer, prostate cancer, breast cancer, esophageal cancer, and skin cancer, and can also be used to treat tumors in many other parts of the body. Interstitial brachytherapy is a cancer therapy in which radioactive material is placed directly into the target tissue at the site of the disease, such as the prostate or breast.

[0014] The dose rate in brachytherapy refers to the level or intensity of radiation delivered to the surrounding medium and can be expressed in grays per hour (Gy / h). In high-dose-rate (HDR) brachytherapy, the dose delivery rate typically exceeds 12 Gy / h. During HDR brachytherapy, the radiation source is positioned for a set duration (typically several minutes or hours) before withdrawal. The specific duration of therapy depends on many different factors, including the desired dose delivery rate and the type, size, and location of the cancer.

[0015] Several imaging techniques, such as X-ray imaging, ultrasound, axial computed tomography (CT) or CAT scans, and magnetic resonance imaging (MRI), can be used to visualize the shape and size of a tumor and its relationship to surrounding tissues and organs. Data from many of these sources can be used to create 3D images of the tumor and surrounding tissues. Using this information, an optimal distribution plan for the radiation source can be developed. This includes considering how the radiation should be arranged and positioned. Incorrect or poor treatment setups can pose safety risks to the patient. Too little or too much radiation must be avoided during treatment, as this can lead to treatment failure and serious side effects.

[0016] Figure 1 An example of interstitial brachytherapy for a tumor 101 in a patient's prostate 103 according to several aspects of this disclosure is illustrated. The size and location of the tumor 101 relative to the patient's urethra 105, bladder 107, and rectum 109 are shown for illustrative purposes. The tumor 101 can be of any size and located anywhere in the prostate 103.

[0017] like Figure 1As shown, the afterloading machine 111 is a radiotherapy machine used for controlling HDR brachytherapy of tumor 101. A delivery tube 115 connects to the afterloading machine 111 to a plastic or metal conduit 117. The delivery tube 115 is designed to allow a steel cable 113 carrying a radiation source 119 from the afterloading machine 111 to the conduit 117. The conduit 117 receives the radiation source 119, and the afterloading machine 111 controls the movement, positioning, and residence time of the radiation source 119 within the tumor 101 according to the physician's treatment plan.

[0018] Interstitial brachytherapy requires the precise placement of a short-range radiation source 119 (such as radioactive isotopes like cobalt-60, iodine-125, cesium-131, iridium-192, etc.) close to the cancerous tumor 101. Radiation therapy aims to kill cancerous tissue while minimizing exposure to healthy tissue. The radiation source 119 can travel the length of a catheter 117 and stop at specific locations for predetermined time periods, thus providing isotropic irradiation of the tissue surrounding the tumor 101. However, if the brachytherapy unit is not properly calibrated, healthy (e.g., non-cancerous) tissue may be incorrectly irradiated.

[0019] Several aspects of this disclosure provide a urinary catheter operable to detect and locate radiation sources. Figure 2 An exemplary arrangement of a urinary catheter according to several aspects of this disclosure is shown. The catheter 201 is located in the urethra. One end of the catheter 201 includes a urine collection port 203 inserted into a bladder 107. This end of the catheter is secured in place by an inflatable balloon 205 at the neck of the bladder 107. The other end of the catheter 201 is connected to an external drainage bag.

[0020] Figure 3A An exemplary urinary catheter 300 for measuring radiation is shown according to several aspects of this disclosure. Multiple radiation sensors are embedded in the wall of the catheter 201. Each radiation sensor includes reference markers 307, 317, 327, scintillators 309, 319, 329, and optical fibers 311, 321, 331. Each reference marker 307, 317, 327 may include a gold tip allowing each radiation sensor to be positioned using an MRI scanner. Each reference marker 307, 317, 327 may be cylindrical and 1 mm or less. Multiple MRI markers can be positioned via an MRI machine after the catheter is placed in the patient and before radiation therapy.

[0021] Each scintillator 309, 319, 329 collects radiation and converts it into a luminous signal with an intensity proportional to the incident radiation level. The scintillator can be an inorganic or organic, or organic scintillating fiber, having a cylindrical shape, to match the cross-sectional shape and size of fibers 311, 321, 331. For example, each scintillator 309, 319, 329 may include a scintillating multiclad fiber (e.g., Saint-Gobain BCF-12) with a diameter of 0.5 mm. Reference marks 307, 317, 327 may have the same diameter as the fiber. Each fiber 311, 321, 331 allows light from the corresponding luminous signal to be transmitted to a plurality of light detection units 313, 323, 335 located outside the patient's body (e.g., photodetectors, photodiodes). Each light detection unit 313, 323, 333 is configured to generate an electrical signal in the presence of light from one of the plurality of scintillators 309, 319, 329. The level of the electrical signal generated by each optical detection unit 313, 323, 333 is proportional to the light incident on each optical detection unit 313, 323, 333. Therefore, the level of the electrical signal generated by each optical detection unit 313, 323, 333 is proportional to the radiation level incident on each scintillator 309, 319, 329. Each of the plurality of optical detection units 313, 323, 333 can be positioned near one of the plurality of scintillators 309, 319, 329 via optical fiber.

[0022] The processor 337 is configured to calculate the position of the radiation source based on electrical signals from multiple optical detection units 313, 323, and 333. The processor 337 can also be configured to calculate the position of the radiation source using triangulation based on the electrical signals from the multiple optical detection units 313, 323, and 333. The processor can also be configured to calculate the velocity of the radiation source 119 based on the electrical signals from the multiple optical detection units.

[0023] Figure 3B A cross-sectional view of an exemplary urinary catheter for measuring radiation according to various aspects of this disclosure is shown. In this cross-sectional view, optical fibers 311, 321, and 331 are shown as being equidistantly spaced around the urinary catheter 201.

[0024] Figure 4A Exemplary arrangements of urinary catheters according to various aspects of this disclosure are shown. Figure 4AIn this process, tumor 101 is irradiated by a radiation source 119 positioned within tumor 101 via a afterloading catheter 117. A urinary catheter may include a second balloon 401, which can inflate to bring the catheter closer to tumor 101. Scintillators 309, 319, and 329 may be located around the balloon 401 and may also be repositioned. For example, multiple scintillators 309, 319, and 329 and multiple optical fibers 311, 321, and 331 may disperse as the balloon 401 inflates. The precise location of the scintillators 309, 319, and 329 can be determined prior to radiation initiation via CT scan or MRI using positioning reference markers 307, 317, and 327.

[0025] Figure 4B Another arrangement of an exemplary urinary catheter according to several aspects of this disclosure is shown. Figure 4B In this configuration, tumor 101 is irradiated by a radiation source 119 positioned within urethra 105 via a afterloading catheter 117 within a urinary catheter. When the second balloon 401 inflates, radiation can reach tumor 101 without directly injecting the afterloading catheter 117 into tumor 101. The afterloading catheter 117 can also be integrated into catheter tube 201.

[0026] The electrical signals generated by an external photodetector can be processed to determine the location of the radiation source 119 via triangulation. Therefore, the catheter can be used for real-time tracking of the afterloading device. This location, determined by the catheter system, can be used as quality control feedback to the afterloading device. The catheter, with or without the afterloading catheter 117, can be disposable.

[0027] Figure 5A , Figure 5B and Figure 5C Cross-sectional / sectional views of alternative exemplary urinary catheters for measuring radiation, according to various aspects of this disclosure, are shown. Figure 5A An exemplary urinary catheter 500 is shown, which includes a fiber optic lumen 503, an inflatable lumen 505, and a urine drainage channel 507. The fiber optic lumen 503 can be used for sensor placement near an inflatable balloon. The inflatable lumen 505 can be used to inflate the balloon. In an exemplary embodiment, the diameter of the catheter 500 may be 4.7 mm, and the diameter of the fiber optic lumen 503 may be 1.3 mm. Variations in these diameters are also contemplated in this disclosure.

[0028] Figure 5B Another exemplary urinary catheter 510 is shown, which includes an expandable lumen 505, a urine drainage channel 507, and three fiber optic lumens 503.

[0029] Figure 5C Another exemplary urinary catheter 520 is shown, which includes an expandable lumen 505, a urine drainage channel 507, and three fiber optic lumens 503.

[0030] Although the system has been described with reference to certain embodiments, those skilled in the art will understand that various changes and equivalents can be made without departing from the scope of the system. Furthermore, many modifications can be made to adapt specific situations or materials to the teachings of this disclosure without departing from the scope of the invention. Therefore, the method and / or system is not limited to the specific embodiments disclosed, but rather the system will include all embodiments falling within the scope of the appended claims.

[0031] As used herein, the terms “circuit” and “circuit line” refer to physical electronic components (i.e., hardware) and any software and / or firmware (“code”) that can configure, be executed by, and / or otherwise associate with the hardware. As used herein, for example, a particular processor and memory may include a first “circuit line” when executing the first one or more lines of code and may include a second “circuit line” when executing a second one or more lines of code. As used herein, “and / or” means any one or more items in a list that are combined by “and / or”. For example, “x and / or y” means any element in the three-element set {(x), (y), (x, y)}. In other words, “x and / or y” means “one or both of x and y”. As another example, “x, y and / or z” means any element in the seven-element set {(x), (y), (z), (x, y), (x, z), (y, z), (x, y, z)}. In other words, “x, y and / or z” means “one or more of x, y, and z”. As used herein, the term “exemplary” means intended to serve as a non-limiting example, instance, or illustration. As used herein, the terms "for example" and "example" list one or more non-limiting examples, instances, or illustrations. As used herein, a circuit is "operable" to execute a function, provided that the circuit includes the hardware and code (if necessary) required to execute the function, regardless of whether the execution of the function is disabled or not enabled (e.g., by user-configurable settings, factory tuning, etc.).

Claims

1. A catheter system for monitoring radiation during radiotherapy, said catheter system comprising: A long catheter body configured for placement inside a patient's body; Multiple radiation response sensing elements are arranged at different longitudinal positions along the conduit body; as well as The signal interface is configured to transmit the signal generated by the sensing element to the processing circuit. The processing circuitry is configured to determine information indicating the location or behavior of a radiotherapy source based on signals generated by the sensing element.

2. The catheter system according to claim 1, wherein, The catheter body is configured for placement within a body cavity and adjacent to the radiotherapy area.

3. The catheter system according to claim 1, wherein, The radiation response sensing element is configured to generate a signal representing the intensity of the detected radiation.

4. The catheter system according to claim 1, wherein, At least one of the sensing elements comprises a scintillation material configured to emit light in response to incident radiation.

5. The catheter system according to claim 1, wherein, The sensing element includes an optical radiation sensor, a semiconductor radiation sensor, or a solid-state radiation sensor.

6. The catheter system according to claim 1, wherein, The sensing elements are arranged circumferentially around the catheter body.

7. The catheter system according to claim 1, wherein, The catheter body includes an expandable portion configured to alter the spatial relationship between the sensing element and surrounding tissue.

8. The catheter system according to claim 1, wherein, Information indicative of the behavior of the radiotherapy source includes at least one of the dwell time, movement, and speed of the radiotherapy source.

9. A radiotherapy monitoring system, comprising: A catheter, configured to be placed inside a patient during radiotherapy; Multiple radiation sensors are connected to the conduit at spaced-out locations; A signal transmission device configured to transmit signals generated by a sensor; as well as The processor is configured to receive signals generated by the sensor and calculate spatial or temporal information associated with the radiotherapy source.

10. The radiotherapy monitoring system according to claim 9, wherein, The processor is configured to determine the position of the radiation therapy source relative to the catheter.

11. The radiotherapy monitoring system according to claim 9, wherein, The processor is configured to verify the delivery of radiotherapy based on the calculated information.

12. The radiotherapy monitoring system according to claim 9, wherein, The radiotherapy source is delivered via a post-loading device.

13. The radiotherapy monitoring system according to claim 12, wherein, The processor is configured to generate feedback that can be used to adjust the operation of the aftermarket unit.

14. The radiotherapy monitoring system according to claim 9, comprising: One or more imaging visible markers are associated with corresponding radiation sensors to facilitate spatial registration.

15. The radiotherapy monitoring system according to claim 9, wherein, The calculated spatial or temporal information can be used to detect deviations from the planned radiotherapy delivery.

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