JP2017500993A - Intraluminal catheter tracking - Google Patents

Abstract

The present invention generally tracks one or more portions of a catheter based at least in part on the radiolucent characteristics of the catheter during intravascular imaging and diagnostic and / or interventional treatment procedures. Regarding the method. The present invention utilizes the space of a radiolucent negative space in a catheter, created by translation of the sensor in the catheter, to track one or more portions of the catheter, particularly the position of the sensor. A superposition system and method for imaging is provided. Thus, when radiopaque contrast is injected into a blood vessel during angiography, the system is improved to track the position of the sensor, which would otherwise be difficult to identify by conventional methods. Provide a way.

Description

Cross-reference of related applications

  This application claims benefit and priority based on US Provisional Application No. 61 / 905,422, filed Nov. 18, 2013. The contents of this document are incorporated herein by reference in their entirety.

  The present invention relates generally to intraluminal procedures, and more specifically to tracking a catheter during diagnostic and / or interventional treatment activities.

  In the coronary arteries, vascular disorders such as stenosis of the vascular lumen, usually caused by atheromatous plaque, cause decreased blood flow to the myocardium, angina pectoris (chest pain), and ultimately myocardial infarction (heart attack). May be generated. Currently, various cardiovascular treatments are available to identify and treat such vascular stenosis. Examples of such treatment are balloon angioplasty and / or stent placement. Diagnostic imaging is used to identify the extent and / or type of obstacle in the blood vessel before and / or during the treatment of the obstacle. Diagnostic imaging allows physicians to ensure proper treatment of pathological blood vessels and confirm the effectiveness of such treatment.

  In general, there are two different aspects of generating diagnostic images for identifying and treating cardiovascular diseases in the vasculature. The first aspect of diagnostic imaging involves generating a radiographic image of blood flow through the vessel lumen. The purpose of generating such a blood flow image is to identify an obstacle in a pathological blood vessel that restricts the blood flow. In general, the area of a vascular lumen is imaged using angiography, which is a two-dimensional representation of one or more blood vessels in a portion of a patient's vasculature infused with a radiopaque contrast agent. Including doing. Two-dimensional angiographic images can also be viewed in real time by fluoroscopy. Fluoroscopic fluoroscopy is used by physicians primarily for visual guidance in the blood vessels of diagnostic / treatment catheters and / or guide wires. Intravascular catheters include, for example, radiopaque markers that are visible on a fluoroscope so that when a catheter is inserted into and / or removed from a patient's body, the physician tracks the position / pathway of the catheter Make it possible.

  The second aspect of intravascular imaging generally involves imaging the blood vessel itself using an intravascular probe mounted on a catheter. Intravascular imaging of blood vessels includes, but is not limited to, lumen cross-section, deposit thickness on vessel walls, diameter of non-pathological portions of blood vessels, length of diseased portions, and atheroma on vessel walls Provides various information about blood vessels, including the structure of sexual plaque.

  Several types of catheter systems have been designed to follow blood vessels and image atherosclerotic plaque deposits on vessel walls. These new imaging modalities include, but are not limited to, intravascular ultrasound (IVUS) catheters, nuclear magnetic resonance imaging (MRI) catheters, and optical coherence tomography (OCT) catheters. Furthermore, thermographic catheters and intravascular elasticity (palpography) catheters are also known to generate vascular image data via intravascular probes. Other proposed catheter modalities include infrared or near infrared imaging. In operation, these intravascular catheter mounted probes are moved along the blood vessel (eg, by a pullback mechanism) in the region where imaging is desired. As the probe passes through the region of interest, a set of image data is acquired that corresponds to a series of “slices” or cross-sections of blood vessels, lumens, and surrounding tissue.

  All of the above vascular imaging aspects offer advantages but also have drawbacks. For example, while providing a means for the identification of serious obstructions in blood vessels and monitoring of devices in real time, angiography and fluoroscopy are part of the incomplete nature of angiographic image data. Because of this, detailed information about blood vessels cannot be provided. Intravascular imaging probes provide a wealth of intravascular information, such as vessel wall composition, but such methods generally lack spatial orientation.

  Because the two imaging aspects are complementary to each other, some current vascular imaging systems use both imaging aspects simultaneously for patient diagnosis and treatment. More specifically, some current systems superimpose data obtained from both aspects and provide a comprehensive coronary vessel image to an interventional cardiologist. Superposition systems and methods are disclosed, for example, in US Patent Application Publication No. 2006/0241465 and US Patent Application Publication No. 2007/0038061, the contents of which are hereby incorporated by reference in their entirety. The

  The patient's vasculature is defined by a fine network of divergent branches and arteries. Therefore, accurate and robust tracking of catheters and transducers used during image-guided coronary intervention is critical for improving clinical workflow and treatment outcomes. Therefore, when superimposing an intravascular imaging scan (eg, IVUS, OCT, etc.) with a catheter on an angiography / fluorescence / X-ray scan, it is important to be able to detect the characteristics of the imaging catheter in the X-ray image. However, existing overlay systems and methods are somewhat limited in their ability to provide accurate tracking of imaging catheters and transducers.

  For example, when an intravascular imaging scan (for example, IVUS, OCT, etc.) by a catheter is superimposed on an angiography / fluorescence / X-ray scan, a radiopaque contrast agent injected into the blood vessel when acquiring a radiographic image Due in part to the use of the catheter, it may be difficult to locate the catheter and transducer. As described above, imaging catheters typically include a radiopaque marker that is placed at a predetermined location along the imaging region of the catheter body. In general, radiopaque markers are placed near the distal end of the catheter, including a sensor region that can translate longitudinally during “pullback” image acquisition. When performing OCT pullback image acquisition, for example, a radiopaque contrast agent is usually injected into the blood vessel, making the entire blood vessel lumen radiopaque and viewing the markers incorporated into the catheter and / or transducer. It's hard. Intravascular contrast agent injection can make it difficult for automated image processing software (or even by the human eye) to track and visualize the position of the catheter. Because the treatment of plaque deposits requires accurate placement of the catheter and avoidance of damage to the vessel wall, inaccurate tracking of the catheter and / or transducer position relative to the vessel may cause most of the vasculature to exist. Can be off-limit for treatment.

  The present invention generally tracks one or more portions of a catheter within a blood vessel during a diagnostic and / or interventional treatment procedure based at least in part on one or more salient features of the catheter. Systems and methods are provided. In one embodiment, during translation of a sensor (eg, an imaging probe) within a catheter, the sensor generally translates longitudinally along the length of the catheter when acquiring intraluminal data. The translation may be a sensor pullback. As a result of the translation of the sensor, an internal or negative space remains in the sheath of the catheter. The negative space can serve as a salient feature used in determining the location of one or more portions of the catheter, including the sensor itself, especially in the presence of contrast agent injected into the blood vessel.

  In some procedures, a contrast agent can be administered to the blood vessel to obtain blood vessel image data. In one embodiment, the contrast agent is radiopaque and may allow acquisition of angiographic images. The negative space of the catheter can have radiolucent properties. As used herein, the term “radiotransparent” generally refers to a property that is substantially transparent to electromagnetic radiation, particularly x-ray and fluoroscopy. Provides improved visualization of intraluminal procedures during angiography, and allows acquisition of angiographic images that can be overlaid with intraluminal data to further assist in visualization and manipulation of sensors in the blood vessel A radiopaque contrast agent is administered to the blood vessel.

  During angiography, the radiolucent negative space within the catheter provides a relatively low attenuation of x-ray exposure, and thus the negative space has a different appearance than the surrounding tissue and / or catheter structure (e.g. Lighter color). Thus, when a radiopaque contrast agent is injected into a blood vessel during angiography, the position of one or more portions of the catheter, such as a sensor, can be tracked based on the associated negative space. More specifically, specific characteristics of the negative space, such as, but not limited to, shape, geometry, and dimensions can be used to determine the position of the sensor. For example, the position of the sensor may be determined based on the length of the negative space (eg, the length of the negative space is approximately equal to the distance the sensor has been moved during pullback).

  Thus, the present invention provides a more accurate system and method for tracking one or more portions of a catheter (eg, an imaging probe) during an angiographic procedure in an overlay system. When physicians using this system perform intraluminal procedures without the disadvantages associated with current systems and methods that rely heavily on radiopaque markers that provide less precise and inaccurate placement The superposition system can be used continuously.

  The system and method of the present invention helps overcome the challenges associated with directly detecting the shadow of a fully filled intravascular transducer so that a physician using the system and method of the present invention can more easily The structures of interest can be identified and returned to these structures. Thus, the time required for the procedure is reduced and the patient and physician are less exposed to x-ray radiation. Furthermore, tracking one or more portions of the catheter based on the systems and methods of the present invention reduces the amount of radiopaque markers that would otherwise be required.

  According to certain aspects, the present invention includes a system for endoluminal procedures. In one embodiment, the system includes a sensor disposed in the catheter capable of acquiring intraluminal data of the conduit and an extraluminal imaging modality capable of acquiring extraluminal image data of the conduit. The system also receives intraluminal data while the sensor in the catheter is translated during acquisition of intraluminal data, and receives extraluminal image data of the conduit and translates the intraluminal data during translation of the sensor. At least one processor is included that overlays the outer image data and detects a radiolucent feature of the catheter in the presence of a radiopaque contrast agent. A radiolucent feature is a section of a catheter having an internal or negative space where no sensor is present, caused by the translation of the sensor. In one embodiment, the at least one processor is further configured to identify a characteristic of the negative space and determine a position of the sensor based at least in part on the identified characteristic.

  According to another aspect, the invention further includes a method for endoluminal treatment. In one embodiment, the method includes obtaining intraluminal data of a conduit with a sensor disposed within the catheter, obtaining extraluminal image data of the conduit with an extraluminal imaging modality, and excluding intraluminal data from the extraluminal data. Superimposing with the image data. The method further includes detecting a radiolucent feature of the catheter in the presence of a radiopaque contrast agent. A radiolucent feature is a section of a catheter having an internal or negative space where no sensor is present, typically caused by translation of the sensor during intracavitary data acquisition. The method further includes identifying the characteristics of the negative space and determining the position of the sensor based at least in part on the identified characteristics of the negative space.

FIG. 1 is a schematic diagram of a system for performing catheter image superposition according to the present disclosure. FIG. 2 is a schematic diagram of the three-dimensional length of an artery including a severe segment. FIG. 3 is a schematic diagram of a portion of the artery shown in FIG. 2 with the longitudinal section removed along line 2 to illustrate the different elements of atherosclerotic plaque. FIG. 4 is a schematic view of the artery of FIGS. 2 and 3 with an imaging catheter according to the present disclosure inserted into the artery. FIG. 5 is a detailed view of the portion of the artery shown in FIG. 4 including the imaging catheter in the artery. 6 is an enlarged view of the distal portion of the imaging catheter of FIG. 5, illustrating the pullback operation of the imaging element. FIG. 7 is a schematic diagram of components of an OCT system according to the present disclosure. FIG. 8 is a block diagram illustrating in detail the OCT imaging engine of the OCT system of FIG. FIG. 9 is a schematic diagram of an OCT patient interface module according to the present disclosure. FIG. 10 shows a pattern followed by an OCT imaging fiber during pullback operation according to the present disclosure. FIG. 11 shows a scan line pattern resulting from the imaging operation of the OCT imaging catheter according to the present disclosure. FIG. 12 is a display of an angiogram of an artery from which an OCT image is generated before image processing according to the present disclosure. FIG. 13 is a display of the angiogram of the artery of FIG. 12 after image processing showing the identified radiolucent characteristics of the catheter.

  In accordance with embodiments of the present invention, image data acquisition equipment and position information and intravascular images associated with imaging probes (eg, IVUS transducer probes) mounted on flexible elongated members (eg, catheters, guidewires, etc.) The method and system are illustrated by the examples described below, including a data / image processor that generates a display that simultaneously provides on a single display. As will be explained in more detail later, the system according to the present disclosure is based at least in part on the radiolucent characteristics of the catheter, and the location of the intravascular imaging catheter in the blood vessel during diagnostic and / or interventional treatment procedures. Configured to track accurately.

  Referring first to FIG. 1, an exemplary system for practicing the present invention in the form of angiography / fluoroscopy and intravascular ultrasound image superposition is schematically shown. Radiation and ultrasound image data acquisition subsystems are generally well known in the art. Regarding the radiographic image data, the patient 10 is arranged on the angiography table 12. The angiography table 12 is arranged to provide sufficient space for the C-arm 14 of the angiography / fluoroscopy unit to be placed in an operable position on the table 10 on the table 12. The radiographic image data acquired by the angiography / fluorescence fluoroscopy C-arm 14 moves to the angiography / fluorescence fluoroscopy processor 18 via the communication cable 16. The angiography / fluorescence fluoroscopy processor 18 converts the radiographic image data received via the cable 16 into angiography / fluorescence fluoroscopy image data. Angiographic / fluoroscopic (“radiation”) image data is initially stored in the processor 18.

  With respect to the portion of the system associated with the acquisition of ultrasound image data, such as an IVUS catheter or the like such that the distal end containing the diagnostic probe 22 (specifically, the IVUS probe) is located near the desired imaging location of the blood vessel. An imaging catheter 20 is inserted into the patient 10. Although not specifically identified in FIG. 1, the radiopaque material placed near the probe 22 provides an indication of the current position of the probe 22 in the radiographic image. As an example, the diagnostic probe 22 generates an ultrasonic wave, receives an ultrasonic echo representing a region near the diagnostic probe 22, and converts the ultrasonic echo into a corresponding electrical signal. Corresponding electrical signals are transmitted to the proximal connector 24 along the length of the imaging catheter 20. The IVUS version of probe 22 can be implemented in a variety of configurations, including single and multi-transducer element configurations. In the case of a multi-transducer element configuration, the transducer array may be arranged, for example, linearly along the major axis of the imaging catheter 20, in a curve with respect to the major axis of the catheter 20, or circumferentially about the major axis.

  Proximal connector 24 of catheter 20 is communicatively coupled to catheter image processor 26. The catheter image processor 26 converts the signal received via the proximal connector 24 into, for example, a cross-sectional image of a blood vessel segment. In addition, the catheter image processor 26 generates a longitudinal cross-sectional image corresponding to the slice of the blood vessel acquired along the length of the blood vessel. The IVUS image data displayed by the catheter image processor 26 is initially stored in the processor 26.

  The type of diagnostic imaging data acquired by the diagnostic probe 22 and processed by the catheter image processor 26 varies from embodiment to embodiment. According to certain embodiments, the diagnostic probe 22 may include one or more sensors (eg, Doppler and so on) for providing hemodynamic information (eg, blood flow velocity and pressure), also referred to as functional flow measurements. (Or pressure). In such embodiments, functional flow measurements are processed by the catheter image processor 26. Thus, the term “image” is broad to include a variety of aspects that represent blood vessel information including blood pressure, blood flow velocity / volume, blood vessel cross-sectional composition, total blood shear stress, shear stress at the blood / blood vessel wall boundary, and the like. Note that it should be interpreted. When obtaining hemodynamic data for a particular portion of a blood vessel, effective diagnosis relies on the ability to visualize the current location of the diagnostic probe 22 within the blood vessel while observing functional flow indicators that represent cardiovascular disease. To do. The overlay of hemodynamics and radiographic images aids accurate treatment of pathological blood vessels. Alternatively, instead of a catheter mounted sensor, the sensor may be mounted on a guide wire, eg, a guide wire having a diameter of 0.018 ″ or less. Thus, according to embodiments of the present invention, not only various types of probes, Various flexible elongated members (eg, catheters, guidewires) on which such probes are mounted at the distal end are used.

  The overlay processor 30 receives IVUS image data from the catheter image processor 26 via line 32 and receives radiation image data from the radiation image processor 18 via line 34. Alternatively, communication between the sensor and the processor is performed via a wireless medium. The overlay processor 30 displays a superimposed image that includes both radiation and IVUS image frames derived from the received image data. In accordance with one embodiment of the present invention, an indicator (eg, a radiopaque marker artifact) is provided on a radiographic image at a location corresponding to simultaneously displayed IVUS image data. The overlay processor 30 first buffers the angiographic image data received from the radiation image processor 18 via line 34 in the first portion 36 of the image data memory 40. Thereafter, during catheterization, IVUS and radiopaque marker image data received via lines 32 and 34 are stored in the second portion 38 and the third portion 42 of the image data memory 40, respectively. The Individually displayed frames of stored image data are appropriately tagged (eg, timestamps, sequence numbers) to associate IVUS image frames with corresponding radiographic (radiopaque marker) image data frames. etc). In one embodiment where hemodynamic data is acquired rather than IVUS data, the hemodynamic data is stored in the second portion 38.

  Additional markers may also be placed on the patient's surface within the field of view of the angiography / fluoroscopic imaging device or at a location near the patient. The location of these markers is used to place radiopaque marker artifacts at precise locations on the angiographic image.

  The overlay processor 30 renders the overlay image from data previously stored in the first portion 36, the second portion 38, and the third portion 42 of the image data memory 40. For example, from the second portion 38, a particular IVUS image frame / slice is selected. The overlay processor 30 identifies the fluorescent X-ray image data in the third portion 42 corresponding to the IVUS image data selected from the second portion 38. Thereafter, the overlay processor 30 superimposes the fluorescent X-ray image data from the third portion 42 on the angiographic image frame extracted from the first portion 36. The superimposed radiation and IVUS image frames are then displayed adjacent to each other on the graphical display device 50 simultaneously. The overlaid image data frame driving the display device 50 is stored in a long-term memory for later review in a separate session from the procedure in which the radiation and IVUS image data stored in the image data memory 40 was acquired. It is also stored in the device 60.

  As generally understood, the system shown in FIG. 1 can be used for intravascular ultrasound (IVUS), angiography, VH (virtual histology), FL-IVUS (forward looking IVUS), IVPA (intravascular photoacoustic). Imaging, FFR (fractional flow reserve) determination, CFR (coronary flow reserve) determination, OCT (optical coherence tomography), CT (computed tomography), ICE (intracardiac echocardiography), FLICE (forward-looking ICE), intravascular palpography, TEE ( any number of medical sensing procedures on the patient, such as transesophageal ultrasound), thermography, MRI (magnetic resonance imaging), mMRI or μMRI (micro-magnetic resonance imaging), or any other medical sensing modality known in the art Can be used to do. In addition, the system may be used to apply one or more therapeutic or therapeutic procedures to the patient, such as radiofrequency ablation (RFA), cryotherapy, atherectomy, or any other medical procedure known in the art. Can be used.

  For example, any target such as body tissue can be imaged by the method and system of the present invention. In some embodiments, the systems and methods of the present invention image within a tissue cavity. Various structures of the gastrointestinal tract, including but not limited to blood vessels, lymphatic and nervous vessels, small intestine, large intestine, stomach, esophagus, colon, pancreatic duct, bile duct, hepatic duct lumen, vas deferens, vagina, uterus And the structure of the urinary tract including the genital tract lumen, including the fallopian tube, collecting duct, tubule, ureter, and bladder, and the head and neck including the sinus, parotid gland, trachea, bronchi, and lung As well as lumens of various physiological structures, including respiratory system structures can be imaged.

  FIG. 2 is a schematic diagram of the three-dimensional length of the artery 100 including a severe part. In FIG. 2, a pathologic artery 100 having a lumen 102 is shown. In the artery 100, blood flows from the proximal end 106 to the distal end 108 in the direction indicated by arrow 104. Within the artery 100, a stenotic region 110 is observed. The arterial wall 112 is composed of three layers: an intima 114, a medial 116, and an outer membrane 118. An outer elastic plate (EEL) 120 separates the inner film 116 and the outer film 118. A stenosis 122 is observed in the artery 100 and restricts blood flow in the artery 100. A flap 124 is shown in the high stress region 126 of the artery 100. Proximal to the stenosis 122 is a fragile region 128 that includes a necrotic core 130. Generally, a rupture occurs in a region such as the fragile region 128.

  FIG. 4 schematically illustrates an imaging catheter having a distal end 134 inserted into the stenotic region 110 of the artery 100. In some embodiments, the imaging catheter 132 is inserted over a guidewire 136 that allows the imaging catheter 132 to be manipulated to a desired location within the artery 100. As shown in FIG. 5, the imaging catheter 132 includes an imaging sensor 138 for imaging the diseased and normal portions of the artery 100. The imaging sensor 138 acquires, for example, a rotary ultrasonic transducer, an ultrasonic transducer element array such as a phased array / cMUT, an optical coherence tomography (OCT) probe, a spectroscopic probe, a vascular endoscope, or intracavity image data. It is another type of imaging sensor. Distal to the imaging sensor 138 is a tapered tip 140 that allows the imaging catheter 132 to easily follow over the guidewire 136, particularly in difficult, tortuous, constricted or occluded blood vessels. To do. In other embodiments, the tapered tip 140 can be closed. The imaging catheter 132 is pulled back or inserted over the desired length of the blood vessel, imaging information is acquired along this desired length, and then from the set of peripheral cross-sectional images acquired from the imaging information, disease and normal A three-dimensional model of the blood vessel wall including the portion is created. Some techniques, such as IVUS, allow blood flow and thrombus imaging.

  FIG. 6 is an enlarged view of the distal portion of the imaging catheter 132 of FIG. 5 illustrating the pullback operation of the imaging sensor 138. As described in more detail herein, an image of lumen 102 of blood vessel 100 can be acquired by imaging sensor 138 via a pullback method. As shown, during pullback, imaging sensor 138 and drive shaft 140 coupled to imaging sensor 138 are in a first position within the sheath indicated by the dashed frame at arrow 146, as indicated by arrow 144. Can be pulled back (and / or rotated) through the catheter sheath 142. The internal space 148 or “negative space” of the catheter sheath 142 remains where the imaging sensor 138 was present before the pullback.

  As described above, one or more portions of the imaging catheter 132 may include one or more radiopaque elements. The term “radiopaque” generally refers to a property that is visible in radiographic images (eg, radiographs) and under fluoroscopic fluoroscopy. As shown, imaging sensor 138 may include, for example, a radiopaque element or marker 141. The drive shaft 140 and guide wire 136 may also include radiopaque markers disposed thereon. Radiopaque marker 141 is visible on the fluoroscope, which allows the physician to track the location / pathway of the catheter as the catheter is inserted into and / or withdrawn from the patient's body To.

  The negative space 148 left in the catheter sheath 142 during pullback can serve as a radiolucent feature. As used herein, the term “radiotransparent” generally refers to a property that is substantially transparent to electromagnetic radiation, particularly X-ray and fluoroscopy. Thus, during fluoroscopic fluoroscopy, the negative space 148 can be used without any significant image quality degradation to the extent that the image cannot be interpreted with respect to lumen abnormalities, angioplasty outcomes, thrombus formation, or vascular occlusion. X-ray radiation attenuation can be provided that is sufficiently low that a body structure such as a coronary artery imaged by an internal contrast agent can be visualized through a catheter. When using a superposition of a catheter-based intravascular imaging scan (eg, IVUS, OCT, etc.) and angiography / fluoroscopy / X-ray scan, as described in more detail herein, the image During guided coronary intervention, the position of one or more portions of the imaging catheter 132, particularly the imaging sensor 138, can be accurately tracked based at least in part on the radiolucent negative space 148.

  In an exemplary embodiment, the present invention provides a system for superimposing images acquired by OCT with angiography / fluoroscopy / x-ray scan. Commercially available OCT systems are used in various applications such as art preservation and diagnostic medicine, eg ophthalmology. OCT is also used in interventional cardiology, for example, to assist in the diagnosis of coronary artery disease. OCT systems and methods are described in U.S. Patent Application Publication No. 2011/0152771, U.S. Patent Application Publication No. 2010/0220334, U.S. Patent Application Publication No. 2009/0043191, U.S. Patent Application Publication No. 2008/0291463, and U.S. Patent Application. Publication No. 2008/0180683, the contents of these documents are hereby incorporated by reference in their entirety.

  In OCT, a light source supplies light to an imaging device to image a target tissue. Within the light source are optical amplifiers and tunable filters that allow the user to select the wavelength of light to be amplified. Wavelengths commonly used for medical applications include near infrared light, eg, about 800 nm to 1700 nm.

  In general, there are two types of OCT systems, a common beam path system and a differential beam path system, which differ from each other based on the optical arrangement of the system. A common beam path system sends all generated light through a single optical fiber to generate a reference signal and a sample signal, while a differential beam path system is where a portion of the light is directed to the sample and the other part The generated light is split so that is directed to the reference plane. Common beam path interferometers are described in more detail, for example, in US Pat. No. 7,999,938, US Pat. No. 7,995,210, and US Pat. No. 7,787,127, The contents of the literature are hereby incorporated by reference in their entirety.

  In a differential beam path system, amplified light from a light source is input to an interferometer, a portion of the light is directed to a sample and the other portion is directed to a reference plane. The distal end of the optical fiber is coupled to a catheter for examining the target tissue during the catheter procedure. Reflected light from the tissue is recombined with the signal from the reference plane to form interference fringes (measured by a photoelectric detector) and accurate depth-resolved imaging of the target tissue at the micron scale Enable. Exemplary differential beam path interferometers are Mach-Zehnder interferometers and Michelson interferometers. Differential beam path interferometers are described in more detail, for example, in US Pat. No. 7,783,337, US Pat. No. 6,134,003, and US Pat. No. 6,421,164, The contents of the literature are hereby incorporated by reference in their entirety.

  FIG. 7 shows a high-level diagram of a differential beam path OCT system according to some embodiments of the present invention. For intravascular imaging, light is delivered to the vascular lumen via a fiber optic based imaging catheter 826. The imaging catheter is connected to software on the host workstation via hardware. The hardware includes an imaging engine 859 and a handheld patient interface module (PIM) 839 that includes user controls. As shown in FIG. 8, the proximal end of the imaging catheter is connected to a PIM 839, which is connected to an imaging engine.

  FIG. 8 provides a detailed view of the components of the imaging engine 859 (eg, bedside unit). The imaging engine 859 houses a power source 849, a light source 827, an interferometer 931, a variable delay line 835, a data acquisition (DAQ) board 855 and an optical control board (OCB) 854. A PIM cable 841 connects the imaging engine 859 to the PIM 839 and an engine cable 845 connects the imaging engine 859 to the host workstation.

  FIG. 9 shows an optical path in a differential beam path system according to an exemplary embodiment of the present invention. Light for image acquisition is emitted from a light source 827. This light is split between an OCT interferometer 905 and an auxiliary or “clock” interferometer 911. Light directed to the OCT interferometer is further split by splitter 917 with an asymmetric split ratio and recombined by splitter 919. Most of the light is directed to the sample path 913 and the remaining part is directed to the reference path 915. The sample path includes an optical fiber that passes through the PIM 839 and the imaging catheter 826 and terminates at the distal end of the imaging catheter from which an image is acquired.

  Typical intravascular OCT involves inserting an imaging catheter into a patient's target vessel using standard interventional techniques and tools such as guidewires, guide catheters, and angiographic systems. The rotation is driven by a spin motor 861 and the translation is driven by a pullback motor 865.

  FIG. 10 shows the movement for image acquisition defined by rotation and translation. The blood in the blood vessel is temporarily swept away by a clear solution for imaging. Detection of solution injection triggers the catheter's imaging core via the PIM or control console and rotates 1002, pulls back, or both, collecting image data that is sent to the console screen. As shown in FIG. 11, the inner core uses light supplied by the imaging engine to supply light to the tissue as an array of A scan lines and detect reflected light.

  FIG. 11 shows the placement of an A-scan within the blood vessel. A scan A11, A12,. . . Interference light is reflected and detected at each location where one of A (N) intersects a feature surface (eg, vessel wall) in vessel 1006. Catheter 826 is pushed or pulled by pullback motor 865 to translate along axis A.

  The detected reflected light is transmitted along the sample path of the interferometer 831 and recombined with the light from the reference path by the splitter. A variable delay line (VDL) 925 on the reference path uses an adjustable fiber coil to match the length of the reference path with the length of the sample path. The reference path length may be adjusted by a stepper motor that translates the mirror on the translation stage under firmware or software control. Free space rays within the VDL 925 experience a greater delay as the mirror moves away from the fixed input / output fiber.

  The combined light from the splitter is split into orthogonal polarization states, resulting in an RF band polarization diversity temporal interference fringe signal. As shown in FIG. 8, the interference fringe signal is converted to photocurrent using a PIN photodiode on OCB851. The interference, polarization separation, and detection steps are performed by a polarization diversity module (PDM) on the OCB. The signal from OCB is transmitted to DAQ855 shown in FIG. The DAQ includes a digital signal processing (DSP) microprocessor and a field programmable gate array (FPGA) to digitize the signal and communicate with the host workstation and the PIM. The FPGA converts the raw optical interference signal into a significant OCT image. In addition, DAQ compresses data as necessary and reduces the image transmission bandwidth to 1 Gbps (for example, compresses a frame with a lossy compression JPEG encoder).

  A scan A11, A12,. . . , A (N) is collected and stored in tangible non-temporary memory. A set of A scans generally defines a B scan. The data for all A scan lines together represent a three-dimensional image of the tissue. A scan line data is commonly referred to as a B scan and can be used to create a cross-sectional image of a tissue, also referred to as a CT image. The A scanline data is processed according to the system and method of the present invention to generate an image of the tissue. By appropriately processing the data (eg, by fast Fourier transform), a two-dimensional image can be created from the three-dimensional data set. The systems and methods of the present invention provide one or more of CT images, ILD, or both.

  As described above, the system according to the present disclosure is configured to superimpose OCT data with angiography / fluorescence fluoroscopy data. Image overlay software combines angiography, OCT, and displacement information to provide the ability to display multiple views of a three-dimensional space around a target physiology on a single or multiple displays. Superimposing the angiographic image with the OCT image can include, for example, dividing the three-dimensional image data. The displayed superimposed image data can be used for guidance in performing percutaneous coronary angioplasty (PCI) in the coronary arteries.

  By using the system and method of the present invention, i.e., using a radiopaque label co-located with an image collector and a catheter having radiopaque features, an intraluminal catheter and portions thereof ( For example, an improved system for locating an imaging sensor) is provided. In principle, the method is co-located with the image collector using, for example, angiography, for example, imaging a portion of a subject's blood vessel using an image collector as part of an imaging catheter, for example. Imaging the subject to determine the location of the radiopaque label, and intravascularly based at least in part on the location of the radiopaque label relative to the radiopaque features of the catheter in the angiogram. Identifying the position of the image.

  FIG. 12 is an angiogram 1100 of a coronary artery in which an OCT image is generated before image processing according to the present disclosure. After the initial image is acquired, a radiopaque contrast agent is administered and an angiographic image can be acquired. Angiography can be performed, for example, using one or more fluoroscopes each mounted on a C-arm. For example, when multiple fluoroscopes are used to achieve higher accuracy and / or to further constrain overlay, each may be positioned at a unique angle. The angle between the two fluoroscopic sequences can be 30-90 °. The fluoroscope image sequence may be two-dimensional.

  Real-time images of the blood vessels are usually displayed on the monitor during the endovascular procedure so that the technician or doctor can see the operation of the guide wire or catheter in real time. The angiogram may be processed by software and displayed on a computer, or the image may be a closed circuit image of a scintillation surface combined with a visible fluorescent material. New fluoroscopes may use flat panel (array) detectors that respond to smaller amounts of X-ray radiation than conventional scintillation surfaces and provide improved resolution.

  As shown in FIG. 12, when a radiopaque contrast medium is injected into a blood vessel, a part of the catheter, particularly the imaging sensor, may be difficult to see. When performing OCT pullback image acquisition, for example, a blood vessel is typically filled with a radiopaque contrast agent, and the entire lumen of the blood vessel becomes radiopaque, with markers incorporated into the catheter and / or transducer Makes it difficult to see. Intravascular contrast agent injection makes it particularly difficult for automated image processing software (or even by the human eye) to track and visualize the position of the catheter. Because treatment of plaque deposits requires accurate placement of the catheter and avoidance of damage to the walls of the blood vessel, inaccurate tracking of the catheter and / or imaging sensor relative to the blood vessel is prevalent in most of the vasculature. Can be off-limit for this procedure.

  FIG. 13 shows the angiogram of FIG. 12 after image processing to better enable tracking of the imaging transducer during the OCT pullback procedure, especially when used in an overlay system. As shown and described at least with respect to FIG. 6, some imaging catheters are not purged with contrast agent within the sheath 142 during acquisition of angiographic images. Thus, the negative space 148 remaining in the catheter sheath 142 during pullback can be radiolucent (eg, filled with air or saline). The radiolucent negative space 148 generally creates a negative space in the x-ray image. The image processing device according to the present disclosure detects a negative space and further determines the position of one or more portions of the catheter, particularly the position of the imaging sensor 138, based on the dimensions (eg, shape, size, etc.) of the negative space 148. May be configured to determine.

  For example, in some embodiments, radiographic features that typically appear as portions along blood vessels and catheters that have a lighter color than the rest of the image using image tagging software or other algorithms. Can be automatically detected. Upon detection of the radiation transmissive negative space 148, for example, the image tagging software can further determine at least the position of the imaging sensor 138 based on the size (eg, length) of the negative space 148. As described above, the negative space 148 results from the pullback of the transducer 138 along the length of the imaging catheter 132. Thus, the length of the negative space 148 created by the pullback can be approximately equal to the length of the transducer 138 moved along the imaging catheter 132. Similarly, image tagging software may be used to automatically locate radiopaque markers that may appear as small spots with darker colors than the rest of the image.

  It should be noted that the systems and methods according to the present invention are not limited to the use of radiopaque contrast agents in tracking the position of one or more portions of a catheter, such as an imaging sensor. In some embodiments, other types of contrast agents may be administered to the blood vessel, depending on the type of sensor used and the extraluminal imaging method. For example, microbubbles may be used for contrast enhancement purposes during the IVUS process, for example, to enhance the contrast of the carotid lumen-wall boundary. Moreover, although the said embodiment was demonstrated regarding the imaging sensor for acquiring intracavity image data, the system and method which concern on this invention are the FFR (fractional flow reserve) probe for measuring the pressure in the blood vessel, for example. And so on, including non-imaging sensors for acquiring various characteristics of the lumen.

  The system and method of the present invention helps overcome the problems associated with directly detecting the shadow of a fully filled intravascular transducer so that a physician using the system can more easily construct structures of interest. Objects can be identified and returned to these structures. Thus, the procedure takes less time and the patient and physician are less exposed to x-ray radiation. Furthermore, tracking one or more portions of an imaging catheter based on the systems and methods of the present invention reduces the amount of radiopaque markers that would otherwise be required.

  Other embodiments are within the scope and spirit of the invention. For example, due to the nature of software, the functions can be implemented using software, hardware, firmware, hardwiring, or any combination thereof. Also, features that implement functions include being physically located at various locations and distributed so that portions of the functionality are implemented at different physical locations. The steps of the present invention may be performed using dedicated medical imaging hardware, a general purpose computer, or both. As those skilled in the art will recognize as necessary or optimal for performing the methods of the present invention, the computer system or machine of the present invention may include one or more processors (e.g., a central processing unit (CPU), GPU ( graphics processing unit), or both), including main memory and static memory that communicate with each other via a bus. A computing device typically includes a memory coupled to a processor and operable via an input / output device.

  Examples of input / output devices include a video display unit (eg, a liquid crystal display (LCD) or a cathode ray tube (CRT)). The computer system or machine according to the present invention includes an alphanumeric input device (for example, a keyboard), a cursor control device (for example, a mouse), a disk drive unit, a signal generation device (for example, a speaker), a touch screen, an accelerometer, and a microphone. , Cellular radio frequency antennas, and network interface devices, which may be, for example, a network interface card (NIC), a Wi-Fi card, or a cellular modem.

  The memory according to the present invention stores one or more instruction sets (eg, software), data sets, or both that embody one or more of the methods or functions described herein. A machine-readable medium may be included. The software may further reside, in whole or at least in part, in the main memory and / or processor during execution by the computer system, and the main memory and processor also constitute a machine-readable medium. The software may further be transmitted and received over the network via a network interface device.

  In an exemplary embodiment, a machine-readable medium may be a single medium, but the term “machine-readable medium” refers to one or more media (eg, centralized) that store one or more instruction sets. Or a distributed database and / or associated cache and server). Also, the term “machine-readable medium” should be construed to include any medium that can be stored, encoded, or transported by a machine to cause the machine to perform the methods of the invention. is there. Accordingly, the term “machine-readable medium” includes, but is not limited to, a solid-state memory (eg, a SIM (subscriber identity module) card, an SD card (secure digital card), a micro SD card, an SSD (solid-state drive). ), Optical and magnetic media, and any other material recording media. Preferably, the computer memory is a tangible non-transitory medium such as any of the above and can be operatively coupled to the processor by a bus. The method of the present invention writes data to memory, i.e., the configuration of particles in a computer memory so that the transformed tangible medium represents a tangible physical object, e.g., an arterial plaque in a patient's blood vessel. Including physical conversion.

  The term “or” as used herein means “and / or” unless stated otherwise.

INCORPORATION BY REFERENCE Throughout this disclosure, other documents such as patents, patent applications, patent publications, professional journals, books, papers, web content, etc. are referenced and cited. All such documents are hereby incorporated by reference in their entirety for all purposes.

Equivalents In addition to those shown and described herein, various modifications and numerous other embodiments of the present invention, including references to scientific and patent literature cited herein, It will be apparent to those skilled in the art from the full content of the disclosure. The subject matter herein contains important information, examples, and guidance that can be adapted to the practice of the invention in its various embodiments and equivalents.

Claims (24)

A system for endoluminal treatment,
A sensor disposed in the catheter capable of acquiring intraluminal data of the conduit;
An extraluminal imaging modality capable of acquiring extraluminal image data of the conduit;
At least one processor,
Receiving the intraluminal data while the sensor in the catheter is translated during acquisition of the intraluminal data;
Receiving the extraluminal image data of the conduit during the translation of the sensor;
Superimposing the intracavitary data with the extraluminal image data;
A processor for detecting a radiopaque feature of the catheter in the presence of a radiopaque contrast agent.   The at least one processor is further configured to identify a characteristic of the radiation transmissive feature and determine a position of the sensor based at least in part on the identified characteristic of the radiation transmissive feature. The described system.   The system of claim 2, wherein the sensor translates longitudinally along the length of the catheter during a pullback process.   The system of claim 1, wherein the radiolucent feature comprises a section of the catheter having an interior space in which the sensor is not present.   The system of claim 4, wherein the interior space comprises one or more radiolucent compositions.   The system of claim 5, wherein the interior space includes air or saline.   The system of claim 6, wherein the identified characteristic is selected from the group consisting of shape, geometry, and size.   The system of claim 7, wherein the identified characteristic is related to a translation of the device.   The system of claim 1, wherein the extraluminal imaging modality is based on x-rays.   The system of claim 9, wherein the extraluminal imaging modality is selected from the group consisting of fluoroscopy, angiography, and combinations thereof.   The sensor is selected from the group consisting of an intravascular ultrasound probe, an optical coherence tomography probe, a spectroscopy probe, a near infrared Raman spectroscopy probe, a coronary flow reserve ratio probe, and combinations thereof. The system according to 1.   The system of claim 1, wherein the processor further displays the radiolucent characteristics of the catheter on a screen. A method for intraluminal treatment comprising:
Obtaining intraluminal data of the conduit with a sensor disposed in the catheter;
Obtaining extraluminal image data of the conduit with an extraluminal imaging modality;
Superimposing the intracavitary data with the extraluminal image data;
Detecting a radiolucent feature of the catheter in the presence of a radiopaque contrast agent.   The method of claim 13, further comprising identifying a characteristic of the radiation transmissive feature and determining a position of the sensor based at least in part on the identified property of the radiation transmissive feature.   The method of claim 14, wherein obtaining the intraluminal image data comprises translating the sensor during intraluminal data acquisition.   The method of claim 15, wherein the extraluminal image data is acquired during the translation of the sensor.   16. The method of claim 15, wherein the sensor translates longitudinally along the length of the catheter during a pullback process.   The method of claim 13, wherein the radiolucent feature comprises a section of the catheter having an interior space in which the sensor is not present.   The method of claim 18, wherein the identified characteristic is selected from the group consisting of shape, geometry, and size.   The method of claim 19, wherein the identified characteristic is related to a translation of the device.   The method of claim 13, wherein the extraluminal imaging modality is based on x-rays.   The method of claim 13, wherein the extraluminal imaging modality is selected from the group consisting of fluoroscopy, angiography, and combinations thereof.   The sensor is selected from the group consisting of an intravascular ultrasound probe, an optical coherence tomography probe, a spectroscopy probe, a near infrared Raman spectroscopy probe, a coronary flow reserve ratio probe, and combinations thereof. 14. The method according to 13.   14. The method of claim 13, further comprising displaying the radiolucent characteristics of the catheter.