A long range blood vessel imaging method and system

Abstract

The embodiment of the specification discloses a long-range blood vessel imaging method and system, wherein the method is applied to a C-arm imaging device, the C-arm imaging device comprises a C-arm, and a ray emitter and a ray detector are arranged at two ends of the C-arm respectively; the method comprises the following steps: injecting a contrast agent into a blood vessel of a target object; acquiring projection data in a spiral scanning manner through the ray emitter and the ray detector at the two ends of the C-arm; and generating an angiogram based on the projection data.

Description

Technical Field

[0001] This specification relates to the field of medical technology, and in particular to a long-range vascular imaging method and system. Background Technology

[0002] Digital subtraction angiography (DSA) is a medical imaging technique used to assess and diagnose lesions or abnormalities in the vascular system. DSA utilizes X-ray imaging principles, injecting a contrast agent (e.g., iodide) into the patient's body and then using X-ray equipment to continuously acquire images. The acquired images can be used to detect and diagnose various vascular diseases, such as arterial stenosis, thrombosis, and aneurysms, helping doctors better determine the location, severity, and blood flow of the lesions to guide subsequent treatment plans.

[0003] Therefore, some embodiments of this specification present a method and system for vascular imaging. Summary of the Invention

[0004] One embodiment of this specification provides a vascular imaging method applied to a C-arm imaging device, wherein a radiation emitter and a radiation detector are respectively provided at both ends of the C-arm; the vascular imaging method includes: injecting a contrast agent into the blood vessels of a target object; acquiring projection data in a spiral scanning manner through the radiation emitter and radiation detector at both ends of the C-arm; and generating an angiographic image based on the projection data.

[0005] In some embodiments, acquiring projection data in a spiral scanning manner through the ray emitters and ray detectors at both ends of the C-arm includes: moving the C-arm along a first direction while controlling the ray emitter to rotate around the first direction, receiving the rays emitted by the ray emitter through the ray detector, and acquiring the projection data.

[0006] In some embodiments, acquiring projection data in a helical scanning manner using ray emitters and ray detectors at both ends of the C-arm includes: moving the C-arm from the scanning starting point along a first direction, while simultaneously controlling the ray emitter to rotate around the first direction and emitting rays, receiving the rays emitted by the ray emitter through the ray detector, and acquiring first projection data; controlling the ray emitter to stop emitting rays and returning the C-arm to the scanning starting point; moving the C-arm from the scanning starting point along a second direction, while simultaneously controlling the ray emitter to rotate around the second direction and emitting rays, receiving the rays emitted by the ray emitter through the ray detector, and acquiring second projection data; wherein the first direction and the second direction are opposite; and determining the projection data based on the first projection data and the second projection data.

[0007] In some embodiments, acquiring projection data in a helical scanning manner using ray emitters and ray detectors at both ends of the C-arm includes: moving the C-arm along a first direction while simultaneously controlling the ray emitter to rotate a first time around the first direction and emitting rays; receiving the rays emitted by the ray emitter through the ray detector to acquire first projection data; stopping the first rotation when it reaches a preset angle; moving the C-arm along the first direction while simultaneously controlling the ray emitter to rotate a second time around the first direction and emitting rays; receiving the rays emitted by the ray emitter through the ray detector to acquire second projection data; wherein the rotation direction of the second rotation is opposite to the rotation direction of the first rotation; and determining the projection data based on the first projection data and the second projection data.

[0008] In some embodiments, the C-arm is connected to a frame, and the frame drives the C-arm to move. The rotation of the C-arm is achieved through at least one of the following methods: the connection between the frame and the C-arm remains unchanged, and the C-arm rotates relative to the frame; the connection is stationary relative to the C-arm, and the frame drives the C-arm to rotate; and the connection is equipped with a slide rail, and the C-arm slides relative to the frame along the slide rail.

[0009] In some embodiments, the connection point between the C-arm and the frame is at the center of the C-arm. Alternatively, the connection point between the C-arm and the frame is offset from the center of the C-arm, and the radiation emitter and the radiation receiver are rotatable relative to the C-arm.

[0010] In some embodiments, the injection of contrast agent into the blood vessels of the target object is performed simultaneously or alternately with the spiral scan.

[0011] In some embodiments, generating an angiography image based on the projection data includes performing rapid reconstruction based on the projection data to obtain a reconstructed image; segmenting blood vessels in the reconstructed image to generate the angiography image; or, acquiring auxiliary projection data; generating a two-dimensional image sequence based on the projection data and the auxiliary projection data; and generating the angiography image based on the two-dimensional image sequence.

[0012] One embodiment of this specification provides a vascular imaging system, which includes a C-arm imaging device. The C-arm imaging device includes a C-arm, and a radiation emitter and a radiation detector are respectively provided at both ends of the C-arm. The vascular imaging system includes: a contrast agent injection module for injecting contrast agent into the blood vessels of a target object; a scanning module for acquiring projection data in a spiral scanning manner through the radiation emitter and radiation detector at both ends of the C-arm; and an image generation module for generating vascular angiography images based on the projection data. Attached Figure Description

[0013] This specification will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein:

[0014] Figure 1 These are schematic diagrams illustrating application scenarios of exemplary vascular imaging systems according to some embodiments of this specification;

[0015] Figure 2 This is an exemplary flowchart of a vascular imaging method according to some embodiments of this specification;

[0016] Figure 3 This is another exemplary flowchart of a vascular imaging method according to some embodiments of this specification;

[0017] Figure 4 This is another exemplary flowchart of a vascular imaging method according to some embodiments of this specification;

[0018] Figure 5 This is a block diagram of an exemplary vascular imaging system according to some embodiments of this specification;

[0019] Figures 6A-6E This is an exemplary schematic diagram of a vascular imaging method according to some embodiments of this specification. Detailed Implementation

[0020] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0021] It should be understood that the terms “system,” “device,” “unit,” and / or “module” used herein are one way to distinguish different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0022] As indicated in this specification and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0023] Flowcharts are used in this specification to illustrate the operations performed by the system according to embodiments of this specification. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, the steps can be processed in reverse order or simultaneously. Furthermore, other operations can be added to these processes, or one or more steps can be removed from them.

[0024] Three-dimensional digital subtraction angiography (3D-DSA) is an advanced digital angiography technique that combines traditional digital subtraction angiography (DSA) with three-dimensional reconstruction technology. 3D-DSA acquires multiple 2D-DSA images sequentially and uses computer reconstruction algorithms to convert these images into a three-dimensional vascular model. Compared to traditional 2D-DSA, 3D-DSA provides more comprehensive and intuitive information about vascular structure. With 3D-DSA, doctors can rotate, zoom, and move the vascular model to observe the vascular system from various angles and perspectives. This helps doctors better assess the location, shape, size, and distribution of vascular lesions, leading to accurate diagnoses and treatment plans.

[0025] CT angiography (CTA) is widely used in the diagnosis of vascular diseases due to its advantages of large-area, rapid scanning, non-invasiveness, and ease of operation, providing important diagnostic evidence for vascular variations and diseases. By injecting contrast agent intravenously, a CT scan can be completed, reconstructing 3D images of blood vessels along the long axis, assisting doctors in diagnosing head and neck vascular diseases, cardiovascular diseases, and peripheral vascular diseases, primarily for preoperative detection. However, intravenous injection introduces nonspecificity issues into CTA; as a medical imaging diagnostic device, CTA examinations are time-consuming for acute patients in the diagnostic and treatment process. Therefore, there is an urgent need to achieve a system that allows for the acquisition of vascular images, diagnosis, and treatment in a single procedure at the treatment site (e.g., a catheterization lab).

[0026] In practical applications, such as in the diagnosis and treatment of stroke, doctors desire to visualize long-range 3D vascular images from the aortic arch to the top of the skull. C-arm X-ray imaging equipment, such as cone-beam computed tomography (CBCT), uses digital subtraction angiography (DSA) to perform both two-dimensional and three-dimensional angiography. DSA typically involves arterial injection of contrast agents. Taking intracranial angiography as an example, 3D-DSA, after cannulation in the internal carotid artery, completes axial three-dimensional vascular imaging of approximately 18cm of the brain, used for intraoperative diagnosis of aneurysms or vascular stenosis, and postoperative evaluation of interventional treatment effectiveness. DSA equipment is the gold standard for diagnosing many vascular diseases and is a key imaging device in interventional treatment. However, current DSA equipment has a small total projection coverage area, resulting in a small reconstructed 3D vascular area. Performing whole-brain vascular imaging requires multiple intracranial angiography sessions, making it impossible to directly achieve 3D vascular imaging from the aortic arch to the top of the skull.

[0027] Helical scanning using a C-arm X-ray imaging system can achieve long-axial soft tissue imaging. However, current CBCT soft tissue contrast resolution is not high, and scanning time is long, thus its long-range tomographic imaging lacks clinical application value.

[0028] Contrast agents are injected into the artery via a high-pressure injector, spreading along the artery with the bloodstream. Continuous injection gradually fills the blood vessel with contrast agent, which then enters the capillaries and veins. The effective period of arterial vascular imaging is limited, thus restricting the scanning time of the imaging equipment. Traditional long-axial spiral scanning protocols do not consider key factors such as contrast agent usage / injection rate and contrast agent diffusion time, and therefore cannot be applied to long-range vascular imaging.

[0029] In view of this, some embodiments of this specification provide a method and system for intraoperative long-axis vascular imaging. On a C-arm X-ray imaging system, an angiographic agent is injected, and X-ray projection is performed using a spiral scanning method. Based on the projection data, a three-dimensional vascular image of the long axis range is quickly and accurately reconstructed.

[0030] Figure 1 This is a schematic diagram illustrating an application scenario of an exemplary vascular imaging system according to some embodiments of this specification.

[0031] like Figure 1 As shown, the application scenario 100 of the vascular imaging system includes a C-arm imaging device 110, a processing device 120, a terminal device 130, a storage device 140, and a network 150.

[0032] The C-arm imaging device 110 can be used to scan a target object within a detection area or a scanning area to obtain the scan data of the target object.

[0033] In some embodiments, the C-arm imaging device 110 includes a C-arm 111, a radiation emitter 112 and a radiation detector 113 respectively disposed at both ends of the C-arm 111, a frame 114, and a high-pressure injector 115.

[0034] In some embodiments, the C-arm is connected to a frame, which can move the C-arm. The connection method may include mechanical joints, electric control, magnetic adsorption, fixed connection, etc., which are not limited in this specification. The above description of the C-arm imaging device is for illustrative purposes only and is not intended to limit the scope of this specification.

[0035] The processing device 120 is capable of processing data and / or information acquired from the C-arm imaging device 110, the terminal device 130, the storage device 140, and / or other components of the application scenario 100 of the vascular imaging system, and analyzing and / or processing the data and / or information. For example, the processing device 120 acquires projection data from the C-arm imaging device 110; based on the projection data, it generates angiographic images.

[0036] In some embodiments, the processing device 120 is a single server or a group of servers. The server group can be centralized or distributed. In some embodiments, the processing device 120 can be local or remote. For example, the processing device 120 can access information and / or data from the C-arm imaging device 110, the terminal device 130, and / or the storage device 140 via a network 150. As another example, the processing device 120 can be directly connected to the C-arm imaging device 110, the terminal device 130, and / or the storage device 140 to access information and / or data. In some embodiments, the processing device 120 is implemented on a cloud platform. For example, the cloud platform includes private cloud, public cloud, hybrid cloud, community cloud, distributed cloud, inter-cloud cloud, multi-cloud, etc., or any combination thereof.

[0037] In some embodiments, the processing device 120 and the C-arm imaging device 110 may be integrated into one unit. In some embodiments, the processing device 120 and the C-arm imaging device 110 may be directly or indirectly connected to work together to implement the methods and / or functions described herein.

[0038] Terminal device 130 can communicate and / or connect to C-arm imaging device 110, processing device 120, and / or storage device 140. In some embodiments, user interaction can be achieved through terminal device 130. In some embodiments, terminal device 130 may include mobile device 131, tablet computer 132, laptop computer 133, etc., or any combination thereof. In some embodiments, terminal device 130 (or all or part of its functions) may be integrated into processing device 120.

[0039] Storage device 140 may store data, instructions, and / or any other information. In some embodiments, storage device 140 may store data (e.g., projection data, etc.) acquired from C-arm imaging device 110, processing device 120, terminal device 130, and / or other sources. In some embodiments, storage device 140 may store data and / or instructions used by processing device 120 to perform or use in order to complete the exemplary methods described herein.

[0040] In some embodiments, storage device 140 may include one or more storage components, each of which may be a separate device or part of another device. In some embodiments, storage device 140 may include random access memory (RAM), read-only memory (ROM), mass storage, removable memory, volatile read-write memory, and any combination thereof. In some embodiments, storage device 140 may be implemented on a cloud platform. In some embodiments, storage device 140 may be part of C-arm imaging device 110, processing device 120, and / or terminal device 130.

[0041] Network 150 may include any suitable network capable of facilitating information and / or data exchange. In some embodiments, at least one component of application scenario 100 of the vascular imaging system (e.g., C-arm imaging device 110, processing device 120, terminal device 130, storage device 140) may exchange information and / or data with at least one other component of application scenario 100 of the vascular imaging system via network 150. For example, processing device 120 may acquire projection data from C-arm imaging device 110 via network 150.

[0042] It should be noted that the above description of application scenario 100 of the vascular imaging system is provided for illustrative purposes only and is not intended to limit the scope of this specification. Those skilled in the art can make various modifications or variations based on the description in this specification. For example, application scenario 100 of the vascular imaging system can achieve similar or different functions on other devices. However, these changes and modifications will not depart from the scope of this specification.

[0043] Figure 2 This is an exemplary flowchart of an image annotation method 200 according to some embodiments of this specification. Figure 2 As shown, method 200 includes the following steps.

[0044] Step 210: Inject contrast agent into the blood vessels of the target object. In some embodiments, step 210 may be performed by the processing device 120 or the contrast agent injection module 510.

[0045] The target object refers to the object being detected. For example, the target object may include a patient seeking medical treatment, a person undergoing a physical examination, or a patient undergoing radiotherapy. In some embodiments, the target object may include a specific part of the body, such as the head, chest, abdomen, arms, legs, or any combination thereof.

[0046] Contrast agents are substances used in medical examinations and diagnosis, typically administered via injection, oral administration, or other routes into the body. Injecting contrast agents into blood vessels can improve the contrast of blood vessels in images such as X-rays and CT scans. In some embodiments, contrast agents include sodium iodide or iodate. In some embodiments, the contrast agent injection module 510 controls a high-pressure injector to inject the contrast agent into the blood vessels of the target object.

[0047] Contrast agents can be injected intravenously or arterially. In some embodiments, the contrast agent injection module 510 can determine the injection site for injecting the contrast agent into the blood vessels of the target object as needed. For example, in lower extremity vascular interventional procedures, the contrast agent is injected into the tibial vein or femoral vein. As another example, when assessing the condition of the entire vascular system, the contrast agent is injected intravenously. Intravenously injected contrast agent is delivered to the entire vascular system, including arteries and veins, thus providing a comprehensive vascular imaging, not just arterial vessels. Yet another example is in cerebral vascular imaging, where the contrast agent is injected at the aortic arch. This is because the contrast agent can reach the brain rapidly from the aortic arch; if injected intravenously (e.g., through a vein in the arm), the contrast agent travels with the bloodstream to the left heart, then to the lungs, then back to the heart, and finally to the brain, a longer process; and intravenous injection imaging typically displays images of multiple vessels, not just arteries.

[0048] In some embodiments, the contrast agent injection module 510 can determine the injection speed, concentration, injection duration, injection start / end time, and injection interval of the contrast agent into the target vessel as needed, to coordinate with the scanning process. For example, the contrast agent injection module 510 can begin injecting the contrast agent into the target vessel 2 seconds before the start of the scanning process. As another example, the contrast agent injection module 510 can stop injecting the contrast agent into the target vessel 2 seconds before the end of the scanning process. More examples of injecting contrast agents into the target vessel can be found in step 220 and... Figure 3 Explanation.

[0049] The vascular imaging methods described in some embodiments of this specification, compared to spiral cone-beam computed tomography (CBCT), incorporate angiography technology, which improves vascular contrast and achieves clear imaging of vessels at all levels. Compared to existing three-dimensional digital subtraction angiography (3D-DSA) methods, it can expand the axial vascular imaging range. For example, in cerebral vascular imaging, injecting contrast agent at the aortic arch can obtain a long-axis 3D vascular imaging range from the aortic arch to the top of the skull in a single imaging session. This aids in surgical assessment, planning, and navigation, reduces related operation time, and lowers the risk of complications caused by catheter invasion of intracranial vessels. Compared to CT angiography (CTA) imaging methods, it avoids the low specificity of intravenous injection, provides higher-resolution 3D vascular imaging results, and eliminates the need for preoperative CTA examinations, significantly reducing preoperative examination time for acute stroke patients and improving the success rate of rescue.

[0050] Step 220: Projection data is acquired in a helical scanning manner using the ray emitters and ray detectors at both ends of the C-arm. In some embodiments, step 220 may be performed by the processing device 120 or the scanning module 520.

[0051] In some embodiments, the scanning module 520 can perform helical scanning during the diffusion phase or the filling phase. The diffusion phase refers to the time period during which the contrast agent gradually diffuses or spreads after being injected into the blood vessel. The filling phase refers to the time period during which the contrast agent fully diffuses into the target blood vessel after being injected into the blood vessel, making the target blood vessel clearly visible.

[0052] Helical scanning refers to scanning while simultaneously performing a helical motion. Helical motion is a combination of rotation and forward movement; by combining rotation and forward movement, an object exhibits helical motion. In helical scanning, the X-ray emitter and / or X-ray detector moves along one direction (e.g., the direction of extension along the length of the scan bed) while rotating around the target object. Helical scanning allows for the acquisition of continuous volumetric data of the scanned area in a single scan.

[0053] In some embodiments, helical scanning is implemented using a C-arm. For example, the scanning module 520 moves the C-arm along the length of the scanning bed via a frame. Alternatively, the scanning module 520 controls the C-arm to rotate around the target object or slide along the arc of the C-arm, causing the radiation emitters and radiation detectors located at its ends to rotate.

[0054] In some embodiments, the connection point between the C-arm and the frame is at the center of the C-arm. For example, as... Figure 1 As shown, the connection point is the center position of the C-arm. The scanning module 520 positions the center position of the C-arm in the moving direction, drives the C-arm to move along the moving direction via the frame, and controls the C-arm to rotate around the moving direction, causing the radiation emitters and radiation detectors at both ends to rotate.

[0055] Projection data refers to data obtained from different angles or directions that reflects the absorption and scattering of X-rays by the tissue of a target object. For example, in brain scans, data reflecting the absorption and scattering of X-rays by brain tissue are obtained from multiple angles, such as above, below, to the side, and / or at an oblique angle.

[0056] In some embodiments, during the spiral scanning process, the scanning module 520 causes the ray emitter at one end of the C-arm to emit rays, and the ray detector at the other end of the C-arm to receive the rays. Based on the measurement of the received rays by the ray detector, projection data is obtained.

[0057] In some embodiments, the scanning module 520 can move the C-arm along the first direction while controlling the ray emitter to rotate around the first direction, and receive the rays emitted by the ray emitter through the ray detector to obtain projection data.

[0058] The first direction refers to one of the directions along the length of the scanning bed. For example, the first direction is... Figure 6A It is either the positive z-axis direction or the negative z-axis direction.

[0059] The rotation of the ray emitter about the first direction as an axis can be a clockwise circular motion or a counterclockwise circular motion.

[0060] For example, such as Figure 6A As shown, in head and neck vascular imaging, the scanning starting point is the aortic arch. The scanning module 520 moves the C-arm along the direction from foot to head while controlling the X-ray emitter to perform counterclockwise circular motion around the direction from foot to head as the axis, so that the X-ray generator at one end of the C-arm performs spiral scanning motion; the X-ray detector receives the X-rays emitted by the X-ray emitter at several positions on the spiral scanning trajectory to obtain projection data.

[0061] In some embodiments, the injection of contrast agent into the blood vessels of the target object is performed simultaneously or alternately with helical scanning.

[0062] Simultaneous administration refers to the simultaneous start and / or termination of contrast agent injection and helical scanning. For example, the contrast agent is injected into the target's blood vessels as the X-ray emitter at one end of the C-arm begins to rotate and emit X-rays. Alternatively, the injection of contrast agent into the target's blood vessels may stop as the X-ray emitter stops rotating and emitting X-rays.

[0063] Interleaved contrast agent injection into the vessel and helical scanning are performed at different times and / or at different times. For example, contrast agent is injected into the vessel before the helical scan begins. Or, for example, contrast agent injection into the vessel is stopped before the helical scan stops.

[0064] At the start of contrast agent injection, the contrast agent may not have diffused into the blood vessels yet, and the visibility of the blood vessels will not improve immediately, nor will the quality of the scanned image improve. Therefore, the scanning module 520 can delay spiral scanning, that is, wait until the contrast agent reaches full capacity before starting spiral scanning.

[0065] For example, such as Figure 6B As shown, contrast agent injection into the blood vessel begins at 0 seconds, and spiral scanning begins at 2.4 seconds; contrast agent is injected again at 9.6 seconds, and spiral scanning begins again at 12 seconds. Curve 610 represents the contrast agent injection concentration curve; stage ①, from 2.4 seconds to 9.6 seconds, is the contrast agent filling stage; stage ②, from 9.6 seconds to 12 seconds, is the contrast agent decay stage; stage ③, after 12 seconds, is the contrast agent filling stage, where the contrast agent reaches a full filling state again.

[0066] During the period when contrast agent injection is stopped, the contrast agent in the blood vessel may not have yet dissipated, and the state of filling may continue for a moment. Therefore, the scanning module 520 can continue spiral scanning, that is, wait until the contrast agent is no longer in a state of filling before stopping the spiral scanning.

[0067] For example, such as Figure 6B As shown, the injection of contrast agent into the blood vessel was stopped at 7.2 seconds, and the spiral scan was stopped at 9.6 seconds; the injection of contrast agent into the blood vessel was stopped again at 16.8 seconds, and the spiral scan was stopped again at approximately 18 seconds.

[0068] Cross-injection of contrast agent and spiral scanning helps to precisely control the scanning process during the optimal time of contrast agent filling, obtain the best image quality in the shortest time, improve scanning efficiency and quality, and reduce the time that patients need to maintain a specific body position or be exposed to radiation, thereby improving patient comfort and safety.

[0069] Step 230: Generate an angiography image based on the projection data. In some embodiments, step 230 may be performed by the processing device 120 or the image generation module 530.

[0070] Angiographic images are images that show the structure, location, and morphology of blood vessels in a target object. Angiographic images can assist in the diagnosis and assessment of vascular diseases, abnormal dilation, stenosis, embolism, etc. In some embodiments, angiographic images can be presented in a three-dimensional format.

[0071] In some embodiments, the image generation module 530 performs rapid reconstruction based on projection data to obtain a reconstructed image; and performs vascular segmentation on the reconstructed image to generate an angiography image.

[0072] In some embodiments, the image generation module 530 can utilize reconstruction algorithms such as Circular FDK, Helical FDK, and Katsevich to perform rapid reconstruction based on projection data to obtain a reconstructed image. In some embodiments, the image generation module 530 can also use methods such as filtering and backprojection to perform rapid reconstruction based on projection data to obtain a reconstructed image.

[0073] In some embodiments, the image generation module 530 performs vessel segmentation on the reconstructed image using one or more methods selected from edge detection, morphological operations, region growing, and active contour models. In some embodiments, the image generation module 530 marks the segmented vessels in the reconstructed image (e.g., by drawing the contours of the vessels in the reconstructed image) to generate an angiography image.

[0074] Based on the projection image and combined with precise reconstruction methods, three-dimensional reconstruction of blood vessels can be completed quickly, enabling real-time viewing of long-range angiography results during the operation.

[0075] Intraoperative long-axis vascular imaging methods can be used in aortic interventional surgery for aortic dissection or thoracic and abdominal aortic aneurysms, as well as lower extremity vascular interventional surgery, to achieve long-axis vascular imaging, which is beneficial for comprehensive observation of vascular lesions.

[0076] By combining angiography and spiral scanning, along with rapid image reconstruction, higher-contrast vascular images can be obtained in a shorter time, providing an efficient imaging basis for emergency surgery.

[0077] Figure 3 This is another exemplary flowchart of a vascular imaging method according to some embodiments of this specification. In some embodiments, method 300 may be used to implement step 220 of method 200 to acquire projection data in a helical scanning manner via X-ray emitters and X-ray detectors at both ends of a C-arm. In some embodiments, method 300 may be executed by processing device 120 or scanning module 520.

[0078] like Figure 3 As shown, method 300 includes the following steps.

[0079] Step 310: Move the C-arm from the scanning starting point along the first direction, while controlling the ray emitter to rotate around the first direction and emitting rays. Receive the rays emitted by the ray emitter through the ray detector to obtain the first projection data.

[0080] For example, such as Figure 6B As shown, in stage ①, the contrast agent in the blood vessel is in a state of fullness. The C-arm moves from the scanning starting point (e.g., the mouth) along a first direction (foot to head direction) while the X-ray emitter emits X-rays and rotates counterclockwise around the first direction. The scanning module 520 receives the X-rays emitted by the X-ray emitter through a X-ray detector and acquires the first projection data.

[0081] The scan start point refers to the initial position of the helical scanning process. The scan start point can be indicated by its location on the surface and / or interior of the target object, the position of the X-ray emitter, and / or the position of the X-ray detector. For example, the scan start point could be the mouth or the aortic arch. Another example is when the X-ray emitter is directly above the midpoint of the scanning bed and / or the X-ray detector is directly below the midpoint of the scanning bed.

[0082] In some embodiments, the scanning module 520 selects an endpoint or a non-endpoint (a point outside the endpoint of the scanning area) of the scanning region as the scanning start point. For example, an endpoint of the scanning region, the center point of the scanning region, or the golden ratio position within the scanning region may be selected as the scanning start point. In some embodiments, the scanning start point may be determined based on scanning requirements. For example, in a single head and neck vascular imaging, an endpoint of the scanning region, i.e., the aortic arch, may be used as the scanning start point. As another example, in a second head and neck vascular imaging, the center point of the scanning region (approximately at the mouth) may be used as the scanning start point.

[0083] Step 320: Control the X-ray emitter to stop emitting X-rays and return the C-arm to the scanning start point.

[0084] For example, such as Figure 6B As shown, in stage ②, the contrast agent in the blood vessel is in a state of dissipation, and the C-arm and the X-ray generator return to the scanning starting point. During this process, the X-ray emitter does not emit X-rays.

[0085] Step 330: Move the C-arm from the scanning starting point along the second direction, while controlling the ray emitter to rotate around the second direction and emitting rays. Receive the rays emitted by the ray emitter through the ray detector to obtain the second projection data; wherein the first direction and the second direction are opposite.

[0086] The second direction refers to the direction along the length of the scanning bed that is opposite to the first direction. For example, Figure 6A In the equation, if the first direction is the positive z-axis direction, then the second direction is the negative z-axis direction.

[0087] For example, such as Figure 6B As shown, in stage ③, the contrast agent in the blood vessel is refilled. The C-arm moves from the scanning starting point (e.g., the mouth) along the second direction (head-to-toe) while the X-ray emitter emits X-rays and rotates clockwise around the second direction. The scanning module 520 receives the X-rays emitted by the X-ray emitter through the X-ray detector and acquires the second projection data.

[0088] It is worth noting that the scanning starting points of the first projection data and the second projection data are the same. Therefore, the first projection data and the second projection data can together form continuous spiral trajectory projection data.

[0089] Using non-endpoints as the scanning starting point and employing a bidirectional spiral scanning trajectory, this approach avoids the scanning time waste caused by the inability of the C-arm to rotate continuously for multiple turns in existing C-arm X-ray imaging systems, as well as the dose waste and poor reconstruction results caused by discontinuous spiral trajectories. It can fully utilize the contrast agent diffusion time and ensure contrast in key areas.

[0090] In some embodiments, the scanning module 520 obtains the first projection data and the second projection data through other methods. In some embodiments, the scanning module 520 obtains the first projection data by moving the C-arm along a first direction, simultaneously controlling the ray emitter to rotate around the first direction and emitting rays, and receiving the rays emitted by the ray emitter through a ray detector; when the first rotation reaches a preset angle, the first rotation is stopped; the second projection data is obtained by moving the C-arm along the first direction, simultaneously controlling the ray emitter to rotate around the first direction and emitting rays, and receiving the rays emitted by the ray emitter through a ray detector; wherein the rotation direction of the second rotation is opposite to the rotation direction of the first rotation.

[0091] For example, such as Figure 6E As shown, in stage ④, the X-ray generator emits X-rays. Starting from the scanning start point, the X-ray generator rotates clockwise / counterclockwise in a circular motion while simultaneously moving in the positive z-axis direction. The X-rays emitted by the X-ray emitter are received by the X-ray detector to acquire the first projection data. The high-pressure injector is controlled to inject contrast agent before the start of stage ④ and to stop injecting contrast agent before the end of stage ④.

[0092] When the ray generator rotates to the preset angle, it stops emitting rays and also stops its circular motion and positive z-axis movement. The preset angle can be the maximum angle that the C-arm can rotate, such as 200 degrees, 400 degrees, etc. The preset angle can also be an optimal angle determined based on experience, such as 180 degrees, 360 degrees, etc.

[0093] In stage ⑤, the X-ray generator emits X-rays. Starting from the end point of rotation in stage ④, the X-ray generator performs a circular motion in the opposite direction to stage ④, while continuing to move in the positive z-axis direction. The X-rays emitted by the X-ray generator are received by the X-ray detector to obtain the second projection data. The high-pressure injector is controlled to inject contrast agent before the start of stage ⑤ and to stop injecting contrast agent before the end of stage ⑤.

[0094] It is worth noting that the scanning endpoint of stage ④ and the scanning starting point of stage ⑤ are the same. Therefore, the first projection data obtained in stage ④ and the second projection data obtained in stage ⑤ can also jointly constitute continuous spiral trajectory projection data.

[0095] Step 340: Determine the projection data based on the first projection data and the second projection data.

[0096] In some embodiments, the scanning module 520 can obtain projection data by stitching together the first projection data and the second projection data.

[0097] In some embodiments, the scanning module 520 can divide the scanning range into multiple sub-ranges, determine the local scanning start point of each sub-range (e.g., the midpoint of the sub-range), and perform scanning on each sub-range. Figure 6B or Figure 6E The steps shown yield multiple sets of local projection data, each set including local first projection data and local second projection data. The scanning module 520 can obtain projection data by stitching together the multiple sets of local projection data.

[0098] Existing C-arms have limited continuous rotation angles, requiring resetting between scans. By pausing contrast agent injection during scan intervals, the amount of contrast agent used can be reduced. By injecting contrast agent before each scan, coinciding the scan period with the contrast agent filling period, the contrast agent filling time can be maximized, allowing for the acquisition of long-range, continuous spiral scanning contrast images despite the limited rotation angle of the C-arm.

[0099] In some embodiments, the rotation of the C-arm is achieved through relative rotation between the C-arm and the frame. For example, as... Figure 1 As shown, the frame and connections remain unchanged, while the C-arm rotates around the first direction.

[0100] It is worth noting that, Figure 1 In this design, the C-arm is in the head position, meaning the plane of the C-arm is parallel to the first direction. This design simplifies the scanning process, but the scanning depth is limited by the radius of the C-arm; that is, the maximum scanning depth is equal to the radius of the C-arm.

[0101] In some embodiments, the rotation of the C-arm is achieved by the frame driving the C-arm to rotate. For example, as... Figure 6CAs shown, the connection point is stationary relative to the C-arm, and the frame drives the C-arm to rotate. The dashed unidirectional arrow on the left represents the movement trajectory of the frame driving the C-arm along the first direction, while the dashed circular arrow represents the movement trajectory of the connection point rotating around the first direction when the frame drives the C-arm to rotate.

[0102] In some embodiments, rotation of the C-arm can be achieved through relative sliding between the C-arm and the frame. In some embodiments, a slide rail is provided at the connection between the frame and the C-arm, for example, Figure 6D The C-arm can slide on the slide rail 640 to move relative to the frame. For example... Figure 6D As shown, the C-arm slides on the slide rail 640. The C-arm moves along the arc of the C-arm, which drives the ray generator at one end of the C-arm to make a circular motion around the center line to achieve helical scanning.

[0103] It is worth noting that, Figure 6D The C-arm is in a vertical position, meaning the plane of the C-arm is perpendicular to the longitudinal central axis of the target object. The C-arm can move along the first direction under the drive of the gantry, so that the helical scan can cover a larger axial range (e.g., the entire body of the patient).

[0104] In some embodiments, the connection between the C-arm and the frame is offset from the center of the C-arm, and the radiation emitter and radiation receiver can rotate relative to the C-arm. For example, as Figure 6C As shown, the connection point is located below the center of the C-arm, and the ray emitter and ray receiver can rotate relative to the C-arm. The axis of relative rotation is the line connecting the center of the ray emitter and the center of the ray receiver.

[0105] It is worth noting that, Figure 6C The C-arm is in a lateral position, meaning that the plane of the C-arm forms an angle of less than 90 degrees with the first direction. Figure 6C In the process, the connection between the frame and the C-arm moves in a circular motion around a first direction and moves in that first direction. The connection between the frame and the C-arm is located to the side of the scanning bed. The rotation trajectory of the connection between the frame and the C-arm is as follows: Figure 6C As shown by the dotted circular arrow in the image, this rotation method allows the C-arm and frame to bypass the scanning bed and target object, solving the problem of insufficient depth when the C-arm is in the head position, and enabling a longer range of helical scanning.

[0106] Because the point of rotation is not at the center of the C-arm during rotation, the relative positions of the radiation emitter and the radiation detector will deflect in reverse during the rotation process. For example, Figure 6C The vertical dashed line shown will be aligned with the first direction ( Figure 6CIf the central axis (dashed line) is not on the same plane (does not intersect), the orientation of the projection will be inconsistent. This phenomenon can be avoided by rotating the ray emitter and ray receiver relative to the C-arm, ensuring the consistency of the projection orientation.

[0107] Figure 4 This is another exemplary flowchart of a vascular imaging method according to some embodiments of this specification.

[0108] In some embodiments, if the angiography image generated in step 230 does not meet preset conditions and / or clinical needs, the angiography image needs to be regenerated. Preset conditions include that the contrast between the blood vessels and surrounding tissues in the angiography image is higher than a preset threshold, such as 5%, which can be manually adjusted when viewing the image; and that the target blood vessel can be segmented based on the angiography image. Clinical needs include that the physician believes the angiography image clearly shows the vascular structure.

[0109] In some embodiments, the image generation module 530 can regenerate the angiography image using method 400. In some embodiments, method 400 can be performed by the processing device 120 or the image generation module 530.

[0110] like Figure 4 As shown, method 400 includes the following steps.

[0111] Step 410: Obtain auxiliary projection data.

[0112] Assisted projection data refers to projection data of a target object acquired without the injection of contrast agents. Assisted projection data can reflect preliminary information about the target object, but due to the lack of contrast enhancement, the contrast of blood vessels is relatively low.

[0113] In some embodiments, the processing device 120 acquires auxiliary projection data using the same and / or similar methods as in step 220.

[0114] Step 420: Generate a two-dimensional image sequence based on the projection data and auxiliary projection data.

[0115] In some embodiments, the processing device 120 obtains a generated two-dimensional image sequence by performing digital subtraction on the projection data and auxiliary projection data.

[0116] Digital subtraction angiography (DSA) is an image processing method that subtracts auxiliary projection data from the projection data. Due to the presence of contrast agent, vascular structures in the projection data become more prominent, while the tissues and / or organs surrounding the blood vessels in the projection data are identical or similar to those in the auxiliary projection data. Therefore, through mathematical operations, subtracting the auxiliary projection data from the projection data yields an image that only shows the blood vessels filled with contrast agent.

[0117] A two-dimensional image sequence is a collection of multiple two-dimensional images. These multiple two-dimensional images are two-dimensional subtraction images of blood vessels at multiple locations and / or angles of the target object.

[0118] In some embodiments, the processing device 120 can perform digital subtraction on each projection data and the corresponding auxiliary projection data to obtain a two-dimensional vascular subtraction image corresponding to the projection data, and combine these two-dimensional vascular angiography images into a two-dimensional image sequence.

[0119] Step 430: Generate angiography images based on the two-dimensional image sequence.

[0120] In some embodiments, the image generation module 530 can generate angiography images based on a two-dimensional image sequence using reconstruction algorithms (e.g., Circular FDK, Helical FDK, Katsevich, etc.) and methods such as filtering and back projection.

[0121] Step 230 eliminates the need for a second scan to obtain auxiliary projection data, reducing radiation exposure for the target subject, decreasing scan time, shortening preoperative examination time, and improving the success rate of rescue. Method 400 serves as a backup plan for use when the quality of the angiographic images generated by step 230 is poor, providing a reliable imaging basis for the surgery.

[0122] Figure 5 This is a block diagram of an exemplary vascular imaging system according to some embodiments of this specification.

[0123] like Figure 5 As shown, in some embodiments, the vascular imaging system 500 may include a contrast agent injection module 510, a scanning module 520, and an image generation module 530.

[0124] The contrast agent injection module 510 can be used to inject contrast agents into the blood vessels of a target subject. For more information on contrast agent injection, please refer to step 210 and its related description.

[0125] The scanning module 520 can be used to acquire projection data in a helical scanning manner using the radiation emitters and detectors at both ends of the C-arm when the contrast agent in the blood vessels of the target object is in a state of fullness. For more information on projection data acquisition, please refer to step 220 and its related description.

[0126] The image generation module 530 can be used to generate angiography images based on the projection data. For more information on angiography image generation, please refer to step 230 and its related description.

[0127] It should be understood that Figure 5The systems and modules shown can be implemented in various ways. For example, they can be implemented by hardware, software, or a combination of both. The systems and modules in this specification can be implemented not only by hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips and transistors, or programmable hardware devices such as field-programmable gate arrays and programmable logic devices, but also by software, for example, executed by various types of processors, or by a combination of the aforementioned hardware circuits and software (e.g., firmware).

[0128] It should be noted that the above description of the system and its modules is for illustrative purposes only and should not be construed as limiting this specification to the scope of the illustrated embodiments. It is understood that those skilled in the art, after understanding the principles of this system, may arbitrarily combine the various modules or construct subsystems connected to other modules without departing from these principles.

[0129] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this specification. Such modifications, improvements, and corrections are suggested in this specification and therefore remain within the spirit and scope of the exemplary embodiments described herein.

[0130] Furthermore, this specification uses specific terms to describe embodiments thereof. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Moreover, certain features, structures, or characteristics in one or more embodiments of this specification can be appropriately combined.

[0131] Furthermore, unless expressly stated in the claims, the order of processing elements and sequences, the use of numbers and letters, or other names described in this specification are not intended to limit the order of the processes and methods described herein. Although various examples have been discussed in the foregoing disclosure of some embodiments of the invention that are currently considered useful, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments; rather, the claims are intended to cover all modifications and equivalent combinations that conform to the spirit and scope of the embodiments described herein. For example, while the system components described above can be implemented using hardware devices, they can also be implemented solely using software solutions, such as installing the described system on existing servers or mobile devices.

[0132] Similarly, it should be noted that, in order to simplify the description disclosed herein and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of embodiments in this specification may sometimes combine multiple features into a single embodiment, drawing, or description thereof. However, this method of disclosure does not imply that the subject matter of this specification requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of a single embodiment disclosed above.

[0133] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of range in some embodiments of this specification are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

[0134] For each patent, patent application, patent application publication, and other material such as articles, books, specifications, publications, and documents referenced in this specification, the entire contents of which are incorporated herein by reference. This excludes historical application documents that are inconsistent with or conflict with the content of this specification, as well as documents that limit the broadest scope of the claims in this specification (currently or subsequently appended to this specification). It should be noted that in the event of any inconsistency or conflict between the descriptions, definitions, and / or terminology used in the supplementary materials to this specification and the content of this specification, the descriptions, definitions, and / or terminology used in this specification shall prevail.

[0135] Finally, it should be understood that the embodiments described in this specification are merely illustrative of the principles of the embodiments described herein. Other variations may also fall within the scope of this specification. Therefore, alternative configurations of the embodiments described herein are intended to be illustrative rather than limiting, and should be considered consistent with the teachings of this specification. Accordingly, the embodiments described herein are not limited to those explicitly introduced and described herein.

Claims

1. A long-range vascular imaging method, the method being applied to a C-arm imaging device, the C-arm imaging device comprising a C-arm, wherein a radiation emitter and a radiation detector are respectively disposed at both ends of the C-arm; the method comprising: Projection data is acquired by spiral scanning through the ray emitters and ray detectors at both ends of the C-arm; Based on the projection data, angiography images are generated; The acquisition of projection data via helical scanning through the ray emitters and ray detectors at both ends of the C-arm includes: The C-arm is moved along a first direction, while the ray emitter is controlled to rotate around the first direction and emit rays. The rays emitted by the ray emitter are received by the ray detector to obtain first projection data. When the first rotation reaches a preset angle, the first rotation stops. The C-arm is moved along a first direction, while the ray emitter is controlled to rotate a second time around the first direction and emit rays. The rays emitted by the ray emitter are received by the ray detector to obtain second projection data. The rotation direction of the second rotation is opposite to that of the first rotation. The projection data is determined based on the first projection data and the second projection data; Alternatively, the acquisition of projection data via helical scanning using ray emitters and ray detectors at both ends of the C-arm includes: The C-arm is moved from the scanning starting point along the first direction, while the ray emitter is rotated around the first direction and the ray emitter is emitted. The ray emitted by the ray emitter is received by the ray detector to obtain the first projection data. The control ray emitter stops emitting rays, and the C-arm returns to the scanning start point; The C-arm is moved from the scanning starting point along the second direction, while the ray emitter is rotated around the second direction and emitted as a ray. The ray emitted by the ray emitter is received by the ray detector to obtain second projection data; wherein the first direction and the second direction are opposite. The projection data is determined based on the first projection data and the second projection data.

2. The method according to claim 1, wherein the C-arm is connected to the frame, and the frame drives the C-arm to move; the rotation of the C-arm is achieved by at least one of the following methods: The connection between the frame and the C-arm remains unchanged, while the C-arm rotates relative to the frame. The connection point is stationary relative to the C-arm, and the frame drives the C-arm to rotate; and The connection is equipped with a slide rail, and the C-arm slides relative to the frame along the slide rail.

3. The method according to claim 2, wherein the connection point between the C-arm and the frame is the center position of the C-arm; or, the connection point between the C-arm and the frame is offset from the center position of the C-arm, and the radiation emitter and the radiation receiver are rotatable relative to the C-arm.

4. The method according to claim 1, wherein generating angiographic images based on the projection data comprises: Based on the projection data, a rapid reconstruction is performed to obtain a reconstructed image; The reconstructed image is segmented into blood vessels to generate the angiography image; Alternatively, obtain auxiliary projection data; A two-dimensional image sequence is generated based on the projection data and the auxiliary projection data; The angiography image is generated based on the two-dimensional image sequence.

5. A long-range vascular imaging system, the system comprising a C-arm imaging device, the C-arm imaging device comprising a C-arm, wherein a radiation emitter and a radiation detector are respectively disposed at both ends of the C-arm; the system comprising: The contrast agent injection module is used to inject contrast agents into the blood vessels of the target object; The scanning module is used to acquire projection data in a spiral scanning manner through the ray emitters and ray detectors at both ends of the C-arm; An image generation module is used to generate angiography images based on the projection data; The acquisition of projection data via helical scanning through the ray emitters and ray detectors at both ends of the C-arm includes: The C-arm is moved along a first direction, while the ray emitter is controlled to rotate around the first direction and emit rays. The rays emitted by the ray emitter are received by the ray detector to obtain first projection data. When the first rotation reaches a preset angle, the first rotation stops. The C-arm is moved along a first direction, while the ray emitter is controlled to rotate a second time around the first direction and emit rays. The rays emitted by the ray emitter are received by the ray detector to obtain second projection data. The rotation direction of the second rotation is opposite to that of the first rotation. The projection data is determined based on the first projection data and the second projection data; Alternatively, the acquisition of projection data via helical scanning using ray emitters and ray detectors at both ends of the C-arm includes: The C-arm is moved from the scanning starting point along the first direction, while the ray emitter is rotated around the first direction and the ray emitter is emitted. The ray emitted by the ray emitter is received by the ray detector to obtain the first projection data. The control ray emitter stops emitting rays, and the C-arm returns to the scanning start point; The C-arm is moved from the scanning starting point along the second direction, while the ray emitter is rotated around the second direction and emitted as a ray. The ray emitted by the ray emitter is received by the ray detector to obtain second projection data; wherein the first direction and the second direction are opposite. The projection data is determined based on the first projection data and the second projection data.

Images