Pre-detection system for contrast medium extravasation of CT enhancement injection based on infrared thermal imaging

Abstract

The application provides a CT enhancement injection contrast agent exosmosis pre-detection system based on infrared thermal imaging, comprising: an infrared thermal imager module, comprising a miniature infrared thermal imaging chip, a signal processing circuit, a wireless communication module and a power supply module, which is used for collecting temperature distribution images of a region around a puncture point; an image processing unit, which is in communication connection with the infrared thermal imager module, and is used for receiving and processing thermal image data; a display terminal, which is used for displaying thermal images, temperature difference images, judgment results and state information in real time; a feedback button, which is used for being held and operated by a patient, and is pressed when the patient feels pain or discomfort at the puncture site; an audible and visual alarm unit, which sends audible and visual alarms when the system judges that there is an exosmosis risk. The application provides a non-contact, visual and low-cost detection scheme, so that a technician can intuitively observe fluid distribution at the puncture site, timely and early discover the possibility of contrast agent leakage and alarm, and reduce the pain of a patient caused by contrast agent leakage.

Description

Technical Field

[0001] This invention belongs to the field of medical photography technology, and in particular relates to a CT contrast agent extravasation pre-detection system based on infrared thermal imaging. Background Technology

[0002] Contrast-enhanced CT scans are a commonly used clinical imaging technique. They involve the rapid intravenous injection of an iodine-containing contrast agent using a high-pressure injector to increase the density difference between diseased and normal tissues, thereby enhancing the detection rate and diagnostic accuracy of lesions. During contrast-enhanced CT injection, contrast agent extravasation is one of the most common complications. Extravasation refers to the leakage of contrast agent into the interstitial spaces outside the blood vessels, which can lead to local swelling, pain, skin ulceration, and in severe cases, even compartment syndrome and tissue necrosis. The reported incidence of contrast agent extravasation in contrast-enhanced CT scans is approximately 0.04%–0.9%. The high flow rate (typically 2–5 mL / s) and high pressure (typically 200–300 psi) of the high-pressure injector further increase the risk and severity of extravasation. Common causes of contrast agent extravasation include: (1) improper placement of the indwelling needle, with the needle tip not fully entering the blood vessel lumen; (2) displacement or dislodgement of the indwelling needle during injection; (3) poor vascular conditions in the patient (such as elderly patients or patients undergoing chemotherapy with fragile blood vessels); and (4) excessively fast injection rate during high-pressure injection, resulting in excessive pressure on the blood vessel wall.

[0003] The existing technologies for detecting contrast agent extravasation have the following shortcomings: (1) The tubing pressure monitoring of the high-pressure injector is located at the pump head. When contrast agent extravasates at the puncture point, the tubing pressure at the pump head may not necessarily increase. Therefore, tubing pressure monitoring cannot effectively detect extravasation at the puncture point. (2) Manual observation by technicians is significantly delayed, and some patients cannot express their discomfort in time. (3) Existing patents use skin surface pressure sensors, which are post-event detections and cannot be predicted. (4) Delayed extravasation is difficult to detect. In clinical practice, there is a special type of extravasation: during the saline flushing test, the puncture status appears normal, but extravasation occurs after the high-pressure injection of contrast agent begins due to reasons such as displacement of the indwelling needle. Existing technologies lack a means to continuously monitor the entire injection process. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a CT contrast agent extravasation pre-detection system based on infrared thermal imaging to overcome the shortcomings of the prior art.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: A CT contrast agent extravasation pre-detection system based on infrared thermal imaging is provided, comprising: The infrared thermal imager module includes a miniature infrared thermal imaging chip, a signal processing circuit, a wireless communication module, and a power supply module, and is used to acquire temperature distribution images of the area around the puncture point. An image processing unit, which is communicatively connected to the infrared thermal imager module, is used to receive and process thermal image data; The display terminal is used to display thermal images, temperature difference images, judgment results, and status information in real time. The feedback button is for the patient to hold and press when the patient feels pain or discomfort at the puncture site. The audible and visual alarm unit issues an audible and visual alarm when the system determines that there is a risk of leakage.

[0006] Furthermore, the CT contrast agent extravasation pre-detection system based on infrared thermal imaging also includes a syringe linkage interface. When the system determines that there is a risk of extravasation, the syringe linkage interface sends a stop command to the high-pressure injector.

[0007] Furthermore, in the infrared thermal imaging-based CT contrast agent extravasation pre-detection system, the infrared thermal imager module is fixed next to the CT examination table via a fixed bracket.

[0008] Furthermore, in the CT contrast agent extravasation pre-detection system based on infrared thermal imaging, the infrared thermal imager module adopts a patch structure, which is directly attached to the skin near the patient's puncture point through a flexible patch to achieve continuous monitoring throughout the process.

[0009] Furthermore, in the infrared thermal imaging-based CT contrast agent extravasation pre-detection system, the flexible patch comprises, from the skin side to the outside, a medical adhesive layer, a flexible substrate layer, and a protective layer.

[0010] Furthermore, in the CT contrast agent extravasation pre-detection system based on infrared thermal imaging, the medical adhesive layer uses a medical-grade low-allergenic adhesive, and the medical adhesive layer has uniformly distributed through holes.

[0011] Furthermore, in the infrared thermal imaging-based CT contrast agent extravasation pre-detection system, the flexible substrate layer is a flexible printed circuit board (FPC) made of polyimide (PI) or thermoplastic polyurethane (TPU) material.

[0012] Furthermore, in the infrared thermal imaging-based CT contrast agent extravasation pre-detection system, the protective layer is encapsulated with a medical-grade TPU film or PU film.

[0013] The beneficial effects of the technical solution of this invention are: - Detection is performed before and during contrast agent injection to predict whether the indwelling needle is correctly placed in the blood vessel. The puncture safety assessment is carried out during the saline flushing stage to detect leakage in time, thereby protecting the operator and eliminating the risk of extravasation before contrast agent injection. This significantly reduces the incidence of extravasation and achieves "preventive detection" rather than "post-operative detection".

[0014] - Visual and intuitive, the judgment results are clear at a glance. Technicians can directly observe the flow or diffusion of cold saline, with real-time monitoring throughout the entire injection process. It has both subjective and objective channels for judgment, ensuring high reliability.

[0015] - Non-contact testing does not affect aseptic operation.

[0016] -Low cost, easy to promote, and the core hardware cost can be controlled within 100 yuan.

[0017] - It can detect a variety of abnormalities. Through morphological analysis of the cooling area, it can distinguish between different types such as complete extravasation, partial extravasation, and needle tip adhesion.

[0018] In summary, this invention provides a non-contact, visual, and low-cost detection solution that allows technicians to intuitively observe the fluid distribution at the puncture site, promptly and early detect the possibility of contrast agent leakage and issue an alarm, thereby reducing the suffering of patients caused by contrast agent leakage. Attached Figure Description

[0019] To further illustrate the above-mentioned objectives, structural features, and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings.

[0020] Figure 1 This is a block diagram illustrating the logical structure of a preferred embodiment of the present invention; Figure 2 This is a diagram illustrating an application scenario of a preferred embodiment of the present invention. In the diagram: 1. Infrared thermal imager module; 2. Image processing unit; 3. Display terminal; 4. Feedback button; 5. Audible and visual alarm unit; 6. Syringe linkage interface. Detailed Implementation

[0021] The terms “invention” and “the present invention” used in this specification are intended to broadly refer to all subject matter of this specification and any of the following patent claims. Statements containing these terms should not be construed as limiting the subject matter described herein or limiting the meaning or scope of any of the following patent claims. Furthermore, this specification does not attempt to describe or limit the subject matter covered by any claim of any particular component, paragraph, statement, or drawing of this application. The subject matter should be understood with reference to the entire specification, all drawings, and any of the following claims. The invention may have other embodiments and be practiced or implemented in other ways. Moreover, it should be understood that the wording and terminology used herein are for illustrative purposes and should not be considered limiting.

[0022] The details of the invention will now be discussed with reference to the accompanying drawings, which are illustrated by way of example only. In the drawings, similar features or components may be labeled using the same reference numerals.

[0023] The use of the terms "comprising," "having," and "including," and variations thereof, herein means to include the items listed herein and their equivalents and additional items. While reference may be made in the description of the drawings to directions such as above, below, upward, downward, backward, bottom, top, front, rear, etc., for convenience, reference is made relative to the drawings. These directions are not intended to literally accept or limit the invention in any form. Furthermore, terms such as "first," "second," "third," etc., are used herein for illustrative purposes and are not intended to indicate or imply importance or significance.

[0024] See Figure 1 As shown, the present invention provides a CT contrast agent extravasation pre-detection system based on infrared thermal imaging, which includes an infrared thermal imager module 1, an image processing unit 2, a display terminal 3, a feedback button 4, and an audible and visual alarm unit 5.

[0025] The infrared thermal imager module 1 includes a miniature infrared thermal imaging chip, a signal processing circuit, a wireless communication module, and a power supply module, and is used to acquire temperature distribution images of the area around the puncture point.

[0026] Image processing unit 2 is connected to infrared thermal imager module 1 for receiving and processing thermal image data. Infrared thermal imager module 1 can specifically be MLX90640 / FLIR Lepton with a temperature resolution of no more than 0.1℃.

[0027] Display terminal 3 is used to display thermal images, temperature difference images, judgment results, and status information in real time.

[0028] Feedback button 4 is for patients to hold and press when they feel pain or discomfort at the puncture site.

[0029] The audible and visual alarm unit 5 issues an audible and visual alarm when the system determines that there is a risk of leakage.

[0030] The system also includes a syringe linkage interface 6. When the system determines that there is a risk of extravasation, the syringe linkage interface sends a stop command to the high-pressure injector.

[0031] In a preferred embodiment, the infrared thermal imager module 1 is fixed next to the CT examination table by a fixed bracket.

[0032] In another preferred embodiment, see Figure 2 As shown, the infrared thermal imager module 1 adopts a patch structure, integrating a miniature infrared thermal imaging chip, signal processing circuit, wireless communication module, and power supply module into a flexible patch. It can be directly attached to the skin near the patient's puncture point for continuous monitoring throughout the procedure. The wireless communication module can use Bluetooth / 2.4GHz radio frequency communication.

[0033] The flexible patch consists of a medical adhesive layer, a flexible substrate layer, and a protective layer, arranged from the skin side to the outside. The patch size limit is ≤60mm×40mm×3mm.

[0034] The medical adhesive layer uses a medical-grade, hypoallergenic adhesive to firmly attach the patch to the skin around the puncture site. The medical adhesive layer has evenly distributed pores to prevent the puncture site from being covered.

[0035] The flexible substrate layer is made of polyimide (PI) or thermoplastic polyurethane (TPU) material, and the thickness of the flexible printed circuit board (FPC) does not exceed 0.3 mm.

[0036] The protective layer is encapsulated with medical-grade TPU or PU film, which is waterproof, sweatproof, and alcohol-resistant.

[0037] The system operation using patch-type infrared thermal imager module 1 is divided into two stages: Stage 1 (pre-detection stage), after the puncture is completed, the patch acquires the baseline temperature image, and then physiological saline is injected, and the system analyzes the morphology of the cooling area; Stage 2 (injection monitoring stage), continuous monitoring is carried out throughout the contrast agent injection process, and extravasation is detected and alarmed immediately if it occurs.

[0038] Compared with fixed bracket systems, the system using patch-type infrared thermal imager module 1 has significant advantages: quick installation (completed in 3 seconds), continuous monitoring, resistance to movement interference, applicability to all parts of the body, and single-use to avoid cross-infection.

[0039] The pre-detection process implemented based on this system: a: Patient preparation, following the standard procedure for CT contrast-enhanced scan.

[0040] b: Install the thermal imaging module. Mount the infrared thermal imaging module on the fixed bracket, with the lens facing the puncture point.

[0041] c: The patient holds the feedback button.

[0042] d: Start pre-detection, the system acquires a 3-second baseline thermal image.

[0043] e: Flush in normal saline. The technician flushes in 3-5 mL of normal saline through the indwelling needle.

[0044] f: Real-time analysis and judgment; the system continuously acquires thermal images at a rate of 10 frames per second.

[0045] g: In normal circumstances, if the situation is deemed safe, the terminal will display a green "Safe" sign; in cases of leakage risk, if the situation is deemed to be at risk of leakage, the system will trigger an alarm.

[0046] Complete workflow of a system based on a patch-type infrared thermal imager module: a: Preparing the patch, the technician takes the patch device out of the sterile packaging.

[0047] b: Apply the patch, placing it approximately 2-5 cm away from the puncture site.

[0048] c: Establish wireless communication; the patch automatically searches for the Bluetooth signal of the display terminal.

[0049] d: Start pre-detection, and acquire a baseline temperature image for 3 seconds using the patch.

[0050] e: Start the injection. If the result is "safe", the technician clicks "Start Injection".

[0051] f: Post-injection care: Remove the patch from the patient's skin and place it in a medical waste bin.

[0052] Example of delayed extravasation detection: In a clinical test case, the patch device detected that the shape of the cooling area changed from linear to diffuse about 18 seconds after the injection started, and immediately triggered an alarm.

[0053] Applicability of patch-type infrared thermal imager modules to different locations: a. Forearm vein (most commonly used): The patch is attached 2cm away from the puncture point, and the thermal imaging chip is aligned with the direction of the puncture point.

[0054] b. Veins on the back of the hand: The skin on the back of the hand is thinner, and temperature changes are more obvious, making the patch detection more sensitive.

[0055] c. Median cubital vein: The blood vessels in this area are relatively thick, making it suitable for high-pressure injection.

[0056] d. Jugular vein (special cases): Patch-type devices are small in size and can adapt to the curved surface of the neck.

[0057] The above are merely preferred embodiments of the present invention and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should recognize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.

Claims

1. A CT contrast agent extravasation pre-detection system based on infrared thermal imaging, characterized in that, include: The infrared thermal imager module includes a miniature infrared thermal imaging chip, a signal processing circuit, a wireless communication module, and a power supply module, and is used to acquire temperature distribution images of the area around the puncture point. An image processing unit, which is communicatively connected to the infrared thermal imager module, is used to receive and process thermal image data; The display terminal is used to display thermal images, temperature difference images, judgment results, and status information in real time. The feedback button is for the patient to hold and press when the patient feels pain or discomfort at the puncture site. The audible and visual alarm unit issues an audible and visual alarm when the system determines that there is a risk of leakage.

2. The CT contrast agent extravasation pre-detection system based on infrared thermal imaging according to claim 1, characterized in that, It also includes a syringe linkage interface, which sends a stop command to the high-pressure injector when the system determines that there is a risk of extravasation.

3. The CT contrast agent extravasation pre-detection system based on infrared thermal imaging according to claim 1, characterized in that, The infrared thermal imager module is fixed next to the CT examination table by a fixed bracket.

4. The CT contrast agent extravasation pre-detection system based on infrared thermal imaging according to claim 1, characterized in that, The infrared thermal imager module adopts a patch structure, which is directly attached to the skin near the patient's puncture point through a flexible patch to achieve continuous monitoring throughout the process.

5. The CT contrast agent extravasation pre-detection system based on infrared thermal imaging according to claim 4, characterized in that, The flexible patch comprises, from the skin side to the outside, a medical adhesive layer, a flexible substrate layer, and a protective layer.

6. The CT contrast agent extravasation pre-detection system based on infrared thermal imaging according to claim 5, characterized in that, The medical adhesive layer uses a medical-grade, low-allergenic adhesive, and the medical adhesive layer has uniformly distributed through-holes.

7. The CT contrast agent extravasation pre-detection system based on infrared thermal imaging according to claim 5, characterized in that, The flexible substrate layer is a flexible printed circuit board (FPC) made of polyimide (PI) or thermoplastic polyurethane (TPU) material.

8. The CT contrast agent extravasation pre-detection system based on infrared thermal imaging according to claim 5, characterized in that, The protective layer is encapsulated using medical-grade TPU film or PU film.

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