Catheter with optical shape sensing capability

Abstract

A catheter having optical shape sensing capabilities is described. The catheter features an elongate tube, one or more septae, and one or more microcavities formed in an axial wall of the tube and / or one or more septae. A single core optical fiber can be configured to be positioned within each of the plurality of microcavities, the optical fiber in the plurality of cavities being spatially distributed to sense strain and return an optical signal having characteristics identifying the sensed strain for three-dimensional rendering of the catheter by a control console during insertion into a patient.

Description

[0001] priority

[0002] This application claims priority to U.S. Provisional Application No. 62 / 983,396, filed February 28, 2020, which is incorporated herein by reference in its entirety. Background Technology

[0003] In the past, intravascular guidance of medical devices (such as guidewires and catheters) has used fluorescence imaging to track device placement. However, this fluorescence imaging method exposes patients and their clinicians to harmful X-ray radiation. Furthermore, in some cases, patients are exposed to potentially harmful contrast agents required for fluorescence imaging.

[0004] Electromagnetic tracking systems have recently been increasingly used in medical applications. While these systems avoid line-of-sight dependence when tracking catheters, they are susceptible to intermittent malfunctions due to electromagnetic interference. More specifically, because electromagnetic tracking systems rely on the measurement of magnetic fields generated by a field generator, they are vulnerable to electromagnetic interference from cellular phones, tablets, laptops, and other consumer electronic devices that emit electromagnetic waves. As a result, electromagnetic tracking systems experience more frequent signal loss and are limited to a finite depth range for signal acquisition.

[0005] This paper discloses a duct with fiber optic shape sensing capability and its operation method, which does not suffer from the disadvantages associated with the electromagnetic tracking system described above. Summary of the Invention

[0006] In brief, the embodiments disclosed herein relate to a conduit characterized by an elongated integrated conduit, a diaphragm (or spacer), and a plurality of cavities formed between the surface of the diaphragm (or spacer) and the inner surface of the wall of the integrated conduit (hereinafter referred to as the "conduit wall"). A plurality of microcavities are formed within the diaphragm and within (or along) the conduit wall to hold corresponding plurality of (optical) core fibers. According to one embodiment of this application, each of the core fibers may constitute a single-core grating fiber, i.e., a single optical transmission medium, such as a cylindrical element of glass or plastic having one or more sensors. Alternatively, according to another embodiment of this application, each of the core fibers may constitute a plurality (two or more) wound transmission medium having sensors.

[0007] More specifically, one embodiment of the conduit includes at least one septum spanning the diameter of the integrated conduit and extending longitudinally to subdivide the opening formed by the integrated conduit to create two cavities. As described below, the septum may be manufactured together with a first microcavity of the plurality of microcavities, wherein the first microcavity is coaxial with the central axis of the integrated conduit by being positioned within a middle portion of the septum at or near the center of the cross-section of the integrated conduit. The dimensions of the first microcavity are determined to hold a core fiber (hereinafter sometimes referred to as a "central core fiber"), wherein the diameter of the first microcavity may be determined to exceed the diameter of the central core fiber. Instead of a single septum, the conduit may include two or more septums extending radially to the conduit wall relative to the center of the cross-section. Moreover, if the first microcavity is positioned coaxially with the central axis, it may be held by a protrusion of the integrated conduit instead of a septum or in another arrangement.

[0008] The pipe wall includes one or more microcavities, such as a second plurality of microcavities, which is a subset of the aforementioned plurality of microcavities. According to one embodiment of this application, each of the second plurality of microcavities can be positioned along the circumference of the pipe wall at a known radius equal to the center of the cross-section of the integrated pipe. For example, the second plurality of microcavities can be laterally aligned (e.g., oriented parallel to a central axis) and axially positioned along the outer circumference of the pipe wall to hold corresponding plurality of core fibers (hereinafter referred to as "outer core fibers"). Alternatively, as described in detail below, the second plurality of microcavities can be laterally aligned and positioned with the outer core fibers co-extruded within the pipe wall.

[0009] According to one embodiment of this application, the dimensions of the second plurality of microcavities are determined to hold corresponding plurality of core fibers (hereinafter referred to as "outer core fibers"), wherein the diameter of each of the second plurality of microcavities may also be determined to be larger than the diameter of the outer core fiber to provide "play" and isolate the core fiber from the forces applied to the catheter surface, but the core fiber is not subjected to such forces. This isolation can provide more accurate shape sensing to determine measurements of the (mechanical) strain experienced by the core fiber, allowing medical device monitoring systems to identify changes in the shape or form of catheters, particularly integrated conduits of catheters, with greater precision.

[0010] According to one embodiment of this application, when deployed as a single-core grating fiber, the core fiber includes a plurality of sensors spatially distributed along its length at least between the near and far ends of an integrated conduit. These distributed sensors can be configured as an array of reflective gratings and positioned at different regions of the core fiber to enable distributed measurements over the entire length or selected portions of the integrated conduit. These distributed measurements can be signal characteristics obtained from reflected light with different spectral widths (e.g., specific wavelengths or specific wavelength ranges). An example of reflected light characteristics can include wavelength shifts in the reflected light caused by strain (e.g., axial strain or other types of mechanical strain).

[0011] According to one embodiment of this application, each sensor may be configured as a reflective grating, such as a fiber Bragg grating (FBG), i.e., an intrinsic sensor corresponding to a permanent, periodic change in refractive index recorded in the core fiber. In other words, the sensor functions as a light reflector with a specific spectral width (e.g., a specific wavelength or a specific wavelength range). As a result, when broadband incident light is provided by an optical source and propagates through the specific core fiber, upon reaching the first sensor in the distributed sensor array for the core fiber, the light with a defined spectral width associated with the first sensor is reflected back to a light receiver within a console, which includes a display and an optical source. The remaining spectrum of the incident light continues to propagate through the core fiber toward the distal end of the integrated conduit. The remaining spectrum of the incident light may encounter other sensors from the distributed sensor array, each of which is configured to reflect light with a different specific spectral width to provide distributed measurements, as described above.

[0012] During operation, multiple light reflections (also referred to as “reflected light signals”) return to the control console from each of the multiple core fibers located within corresponding microlumens formed within the catheter. Each reflected light signal can be uniquely associated with a different spectral width. The information associated with the reflected light signals can be used to determine a three-dimensional representation (hereinafter also referred to as the “physical state of the catheter”) of the physical state (e.g., shape, length, form, and / or orientation) of a portion of the catheter within the patient (e.g., tip, tubular portion, etc.) or the catheter as a whole. Here, the outer core fibers are spatially separated along the circumferential space of the tubular wall, and each outer core fiber is configured to individually return light with different spectral widths (e.g., specific wavelengths or wavelength ranges) reflected from a distributed sensor array fabricated in each of the core fibers. The comparison of the wavelength shift of the reflected light detected from the outer core fibers with the wavelength shift of the reflected light from the central core fiber, used as a reference operation, can be used to determine the physical state of the catheter.

[0013] More specifically, during vascular system insertion, clinicians can rely on a console to visualize the current physical state of the catheter (e.g., shape, orientation, etc.) to avoid potential path deviations caused by changes in catheter orientation (e.g., changes in the angular orientation of the integrated conduit). When the outer core fibers are located within a plurality of microlumens laterally aligned at different locations along the circumference of the conduit wall, changes in the angular orientation (bending) of the catheter's integrated conduit will apply different types (e.g., compression or tension) and degrees of strain to each of the outer core fibers and the central core fiber. Different types and / or degrees of strain can cause different wavelength shifts to be applied to the sensors on the core fibers, and these wavelength shifts can be measured to extrapolate the physical state of the catheter.

[0014] These and other features of the embodiments of the invention will become clearer from the following description and appended claims, or may be learned through practice of the embodiments of the invention set forth below. Attached Figure Description

[0015] A more specific description of this application will be presented with reference to specific embodiments illustrated in the accompanying drawings. It should be understood that these drawings depict only exemplary embodiments of the invention and should not be considered as limiting its scope. Exemplary embodiments of the invention will be described and explained in more specific and detailed manner using the accompanying drawings, in which:

[0016] Figure 1 This is an illustrative embodiment of a medical device monitoring system that includes a medical device with optical shape sensing capabilities;

[0017] Figure 2 During catheter insertion into the patient and the procedure Figure 1 An exemplary embodiment of a medical device monitoring system;

[0018] Figure 3A yes Figure 1-2 Illustrative examples of catheters.

[0019] Figure 3B Is Figure 3A An illustrative embodiment of the microlumen and core fiber deployment in the integrated conduit of the catheter shown.

[0020] Figure 4A yes Figures 3A-3B A perspective view of a first illustrative embodiment of a catheter, the catheter including an integrated conduit, a diametrically disposed diametrically, and microcavities formed within the conduit and the diaphragm;

[0021] Figure 4B It includes the core fiber installed within the microcavity. Figure 4A A perspective view of a first illustrative embodiment of the catheter;

[0022] Figure 5 yes Figures 3A-3B A perspective view of a second illustrative embodiment of a conduit, the conduit including an integrated tubing, a diametrically disposed diaphragm, a radially disposed diaphragm, and microcavities formed within the tubing and diaphragms; and

[0023] Figures 6A-6B It is by Figure 1 The flowchart shows the operation method for achieving optical three-dimensional shape sensing in a medical device monitoring system. Detailed Implementation

[0024] Referring now to the accompanying drawings, in which the same structures will have the same reference numerals. It should be understood that the drawings are illustrative and schematic representations of exemplary embodiments of the invention, and are neither limiting nor necessarily drawn to scale.

[0025] Regarding the terminology used herein, it should be understood that these terms are for describing certain specific embodiments and do not limit the scope of the concepts provided herein. Ordinal numbers (e.g., first, second, third, etc.) are generally used to distinguish or identify different components or operations and do not provide for serial numbers or numerical limitations. For example, the components or operations “first,” “second,” and “third” do not necessarily appear in sequence, and a particular embodiment including such components or operations is not limited to these three components or operations. Similarly, labels such as “left,” “right,” “top,” “bottom,” “front,” and “rear” are used for convenience and are not intended to imply, for example, any particular fixed position, orientation, or direction. Rather, such labels are used to reflect, for example, relative position, orientation, or direction. Unless the context clearly specifies otherwise, the singular forms “a,” “an,” and “the” include plural references.

[0026] In the following description, the terms “or” and “and / or” as used herein shall be interpreted as inclusive or referring to any one or any combination thereof. As an example, “A, B, or C” or “A, B, and / or C” means “any one of the following: A; B; C; A and B; A and C; B and C; A, B, and C”. Exceptions to the definition occur only when the combination of elements, components, functions, steps, or actions is inherently mutually exclusive in some way.

[0027] The term "logic" refers to hardware and / or software configured to perform one or more functions. As hardware, logic can include circuitry with data processing and / or storage capabilities. Examples of such circuitry include, but are not limited to, processors, programmable gate arrays, microcontrollers, application-specific integrated circuits (ASICs), combinational circuits, etc. Alternatively, or in combination with the aforementioned hardware circuitry, logic can be software in the form of one or more software modules that can be configured to operate as their corresponding circuitry. Software modules can include, for example, executable applications, daemon applications, application programming interfaces (APIs), subroutines, functions, procedures, routines, source code, or even one or more instructions. Software modules can be stored in any suitable non-transient storage medium, such as programmable circuitry, semiconductor memory, non-persistent storage devices such as volatile memory (e.g., any type of random access memory "RAM"), persistent storage devices such as non-volatile memory (e.g., read-only memory "ROM", power-backup RAM, flash memory, phase-change memory, etc.), solid-state drives, hard disk drives, optical disk drives, or portable storage devices.

[0028] For clarity, it should be understood that the term "proximal" refers to a direction relatively closer to the clinician using the device described herein, while the term "distal" refers to a direction relatively farther from the clinician. Here, the "proximal portion" of the integrated conduit of the catheter disclosed herein includes, for example, a portion of the catheter conduit intended to be close to the clinician when the catheter is used on a patient. Similarly, the "proximal end" of the catheter conduit includes, for example, an end intended to be close to the clinician when the catheter is used. The proximal portion of the catheter conduit may include the proximal end of the catheter conduit; however, the proximal portion of the catheter conduit does not necessarily need to include the proximal end of the catheter conduit.

[0029] Similarly, the “distal portion” of the integrated conduit of the catheter includes the portion of the catheter conduit intended to be proximate to or within the patient when the catheter is used in the patient. Likewise, the “distal end” of the catheter conduit includes the end of the catheter conduit intended to be proximate to or within the patient when the catheter is in use. The distal portion of the catheter conduit may include the distal end of the catheter conduit; however, the distal portion of the catheter conduit does not necessarily need to include the distal end of the catheter conduit. Furthermore, the words “comprising,” “has,” and “having” as used herein (including the claims) shall have the same meaning as the word “comprising.”

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art.

[0031] Reference Figure 1 An exemplary embodiment of a medical device monitoring system 100 is illustrated. Here, the medical device monitoring system 100 is characterized by a console 110 and a medical device 120 communicatively coupled to the console 110. In this embodiment, the medical device 120 corresponds to a catheter, characterized by an integrated conduit 130 having two or more lumens 135 extending between a proximal and distal end 132 of an integrated conduit 130. The integrated conduit 130 (sometimes referred to as a “catheter conduit”) communicates with one or more extension legs 140 via a bifurcation hub 142. An optically based catheter connector 144 may be included on the proximal end of at least one extension leg 140 to enable the catheter 120 to be operatively connected to the console 110 via an interconnect 145 or another suitable component. Here, interconnect 145 may include connector 146, which, when coupled to an optically based conduit connector 144, establishes optical connectivity between one or more optical fibers 147 (hereinafter referred to as "optical fibers") included as part of interconnect 145 and core fibers 137 deployed within conduit 120 and integrated into conduit 130. Alternatively, different combinations of connectors including one or more adapters may be used to optically connect optical fibers 147 to core fibers 137 within conduit 120.

[0032] An exemplary implementation of console 110 includes a processor 160, memory 165, a display 170, and optical logic 180; however, it will be understood that console 110 may take one of various forms. The processor 160 is included to control the functionality of console 110 during operation when accessing memory 165 (e.g., non-volatile memory). As shown, display 170 may be a liquid crystal diode (LCD) display integrated into console 110 and serves as a user interface to display information to clinicians, particularly during catheter placement procedures (e.g., cardiac catheterization). In another embodiment, display 170 may be separate from console 110. For both embodiments, the content presented by display 170 may constitute a two-dimensional (2-D) or three-dimensional (3-D) representation of the physical state of catheter 120 (e.g., the length, shape, form, and / or orientation of catheter 120 or a portion thereof) calculated based on the characteristics of the reflected light signal 150 returned to console 110. According to one embodiment of this disclosure, the reflected light signal 150 may be associated with various discrete portions (e.g., specific spectral widths) of the broadband incident light 155 transmitted from and provided by optical logic 180 as described below.

[0033] Still referencing Figure 1 Optical logic 180 is configured to support the graphical representation of the conduit 120, and particularly its integrated conduit 130, based on the characteristics of the reflected light signal 150 received from the conduit 120. These characteristics may include wavelength shifts caused by strain on certain regions of the core fiber 137 integrated within (or along) the wall of the integrated conduit 130, which can be used to determine (through calculation or extrapolation of the wavelength shift) the physical state of the conduit 120, and particularly its integrated conduit 130, or a portion of the integrated conduit 130 (e.g., the tip or distal end of the conduit 130), to read fluctuations (real-time movement) at the tip (or distal end).

[0034] More specifically, optical logic 180 includes a light source 182. The light source 182 is configured to transmit broadband incident light 155 for propagation on optical fibers 147 included in an interconnect 145, which is optically connected to a plurality of core fibers 137 within a conduit 130. In one embodiment, the light source 182 is a tunable swept-frequency laser; however, other suitable light sources may be used besides lasers, including semi-coherent light sources, LED light sources, etc.

[0035] According to one embodiment of this application, the optical logic 180 further includes a light receiver 184 (e.g., a photodetector, such as a positive-intrinsic-negative "PIN" photodiode, avalanche photodiode, etc.). Here, the light receiver 184 is configured to: (i) receive the returned optical signal, i.e., the reflected optical signal 150 received from the fiber-based reflective grating (sensor), the reflective grating (sensor) being fabricated in each of the core fibers 137 deployed within the conduit 120 (see [link to relevant documentation]). Figure 3B (ii) converting the reflected light signal 150 into reflected data 185, i.e., data representing the reflected light signal in electrical signal form, including wavelength shifts caused by strain. As described below, the reflected light signal 150 associated with different spectral widths includes a reflected light signal 151 provided from a sensor located in the central core fiber (reference) of the conduit 120 and a reflected light signal 152 provided from a sensor located in the outer core fiber of the conduit 120.

[0036] As shown, both the light source 182 and the light receiver 184 are operatively connected to a processor 160 that controls their operation. Furthermore, the light receiver 184 is operatively coupled to provide reflection data 185 to a memory 165 for storage and processing by reflection data classification logic 190. The reflection data classification logic 190 can be configured to (i) identify which core fibers are associated with which of the received reflection data 185, and (ii) separate the reflection data 185 provided by the reflected light signal 150 relating to similar regions and / or spectral widths of the conduit 120 into analysis groups. The reflection data of each analysis group is available for analysis by the shape sensing logic 195.

[0037] According to one embodiment of this application, shape sensing logic 195 is configured to compare the wavelength shift measured by sensors deployed in each outer core fiber at the same measurement region (or the same spectral width) of the catheter with the wavelength shift at the central core fiber positioned along the central axis and operating as a curved neutral axis. Based on these analyses, shape sensing logic 190 can determine the shape adopted by the core fiber in 3-D space and can further determine the current physical state of the catheter 120 in 3-D space for presentation on display 170.

[0038] According to one embodiment of this application, shape sensing logic 195 can generate a representation of the current physical state of conduit 120, particularly integrated conduit 130, based on a trial-and-error method or runtime analysis. For example, shape sensing logic 195 can be configured, according to machine learning techniques, to access a data memory (library) containing pre-stored data (e.g., images) related to different regions of conduit 120, where core fibers 137 undergo similar or identical wavelength shifts. Based on the pre-stored data, the current physical state of conduit 120 can be represented. Alternatively, as another example, shape sensing logic 195 can be configured to determine, during operation, changes in the physical state of each region of conduit 120, particularly conduit 130, based at least on (i) the wavelength shifts experienced by the core fibers and (ii) the relationship between these wavelength shifts generated by sensors located at different outer core fiber locations along the same cross-sectional area of ​​conduit 120 and the wavelength shifts generated by sensors at the same cross-sectional area of ​​the central core fiber. It is conceivable that other processing and procedures could be performed to utilize the wavelength shift measured by sensors along each of the core fibers 137, thereby producing appropriate changes in the physical state of the conduit 120.

[0039] Now for reference Figure 2 An embodiment of catheter 120 is shown, illustrating insertion of catheter 120 into the vascular system of patient 200 through skin insertion site 210. Here, catheter 120 typically includes an integrated conduit 130 having a proximal portion 220 that is generally retained outside patient 200 and a distal portion 230 that is generally located within the patient's vascular system after placement. The (integrated) catheter conduit 130 can be advanced to a desired location within the patient's vascular system, for example, with the distal end (or tip) 235 of catheter 130 close to the patient's heart, such as in the lower third (1 / 3) portion of the superior vena cava (SVC). In this embodiment, various instruments can be placed at the distal end 235 of catheter 130 to measure blood pressure in a ventricle and vessel, observe the interior of the vessel, etc.

[0040] During its passage through the patient's vascular system, catheter conduit 130 receives broadband incident light 155 from console 110 via optical fiber 147 within interconnect 145, wherein the incident light 155 propagates to core fiber 137 within catheter conduit 130. According to one embodiment of this application, connector 146 of interconnect 145 terminating optical fiber 147 may be coupled to an optically based catheter connector 144, which may be configured to terminate core fiber 137 deployed within catheter 120. This coupling optically connects core fiber 137 of catheter 120 to optical fiber 147 within interconnect 145. Optical connectivity is required to propagate incident light 155 to core fiber 137 and return reflected light signal 150 to optical logic 180 within console 110 via interconnect 145. As described in detail below, the physical state of catheter 120 may be determined based on analysis of the wavelength shift of reflected light signal 150.

[0041] Reference Figure 3A , showed Figure 1-2 An illustrative embodiment of the conduit 120. Here, the conduit 120 includes an integrated conduit 130 and at least one diaphragm 310, the diaphragm 310 extending across the diameter "d" of the conduit 130 and positioned at the distal end 235 of the conduit conduit 130. The diaphragm 310 helps to form a plurality of cavities 320 within the conduit 130 between the inner surface 305 of the wall 300 forming the conduit 130 and the surface of the diaphragm 310 extending longitudinally from the distal end 235 toward the bifurcation hub 142 of the conduit 120. A plurality of microcavities 3301-330 N (N≥3) Determine the size to have fewer than 320 cavities (e.g.) Figure 4A The diameter of either of the cavities 400 and 410 can be commonly formed within the partition 310 and along the circumference of the conduit 130, for example, formed in the wall 300 of the integrated conduit 130 itself (e.g., one or more microcavities, such as microcavities 3302-3304 fabricated between the inner surface 305 and the outer surface 307 of the wall 300) or as longitudinal beads formed on the inner surface 305 or the outer surface 307 of the wall 300. These microcavities 3301-330... N Configured to retain the corresponding multiple core fibers 3401-340 N ,like Figure 3B As shown.

[0042] More specifically, such as Figures 3A-3BAs shown, the conduit 120 includes at least one septum (e.g., septum 310) spanning a diameter “d” across the conduit 130 and extending longitudinally to subdivide the opening 350 formed by the conduit 130 to create a cavity 320. The septum 310 may be manufactured as part of the conduit 120 during extrusion, or it may be manufactured as a separate component during manufacturing and inserted into the conduit's conduit. Alternatively, the conduit 120 may be configured such that the septum 310 does not divide the opening 350, because a portion of the wall 300 may protrude into the cross-sectional space occupied by the distal end of the conduit (the area at the opening 350), or a portion of the wall 300 may protrude into the cross-sectional space occupied by the distal end of the conduit (the area at the opening 350), wherein a central microcavity 3001 is formed within the protruding portion of the wall 300 to hold one or more core fibers.

[0043] As described below, the partition 310 uses the aforementioned multiple microcavities 3301-330 N The first microcavity 3301 is manufactured in the integrated conduit 130 by positioning it within the middle portion of the partition 310 at or near the cross-sectional center 365 of the integrated conduit 130, with the first microcavity 3301 coaxial with the central axis 360 of the integrated conduit 130. The cross-sectional center 365 is the center position from the cross-sectional area facing the distal end 235 of the integrated conduit 130. Here, the first microcavity 3301 is configured to hold a single core fiber 3401 (hereinafter referred to as the "central core fiber"). A plurality of microcavities 3301-330 are positioned along the circumference 370 of the integrated conduit 130. N The second set of multiple microcavities 3302-330 N Microcavity 3302-330 N Maintain the corresponding core fiber 3402-340 N (Hereinafter referred to as "outer core fiber"). According to one embodiment of this application, as shown in the figure, one or more outer core fibers (e.g., a second plurality of core fibers 3402-340) N Located in different quadrants along the circumference 370 of the integrated conduit 130, such as Figure 4B As shown.

[0044] like Figure 3B As shown, each core fiber has 340 i (1≤i≤N) includes a sensor array 380 spatially distributed along the length of the conduit 130, at least between the proximal and distal ends. i1 -380 iM (1≤i≤N; M≥2). 380 per sensor. i1 -380 iM It can be positioned along the core fiber 340 i Different measurement areas 3851-385 of the specified length distributionM At this location, in an attempt to sense what is occurring in these fiber optic regions 3851-385 M The strain at the site, especially during the advancement of catheter 120 within the patient's vascular system. The distribution length can be static or variable.

[0045] More specifically, sensor 380 i1 -380 iM (i=1…N, such as Figure 3B Each of the sensors (as shown) is configured to reflect light at different spectral widths (e.g., a specific wavelength or a specific wavelength range), wherein adjacent sensors (e.g., sensor 380) i1 -380 i2 Sensor 380 i2 -380 i3 (etc.) can be arranged to reflect light with non-overlapping spectral widths. However, in response to core fiber 3402 (i=2) in fiber region 3851-385 M Any of these (e.g., fiber optic region 3851) is subjected to strain, sensor 380 21 It also undergoes strain, which causes the sensor to 380 21 The characteristics of the reflected light signal are altered to represent the sensed strain. As a result, overall, the strain is represented by sensor 380. i1 -380 iM Along each core fiber 3401-340 N The returned reflected light signal can be used by console 110 to recover reflection data for determining the core fiber 3401-340. N The current 3-D shape. Based on core fiber 3401-340. N The current 3D shape can be used to determine the current 3D shape of the conduit 120 for subsequent drawing.

[0046] For ease of discussion, the operation of the selected core fiber 3402 and the sensor 380 deployed on the core fiber 3402 will be discussed. 21 -380 2M Operation. Other core fibers 3401, 3403… and / or 340… N It can be configured in a similar or identical way.

[0047] According to one embodiment of this application, each sensor 380 21 -380 2M It can be configured as a fiber Bragg grating (FBG), that is, an intrinsic sensor corresponding to a permanent periodic refractive index change, inscribed within the core fiber 3402. In other words, each sensor 380 21 …and 380 2MAs light mirrors with different specific spectral widths, when broadband incident light 155 is provided by an optical source and propagates through the core fiber 3402, it reaches the first sensor 380 located in the first region 3851 of the core fiber 3402. 21 At that time, it has a target for the first sensor 380 21 The light 152 of the selected spectral width is reflected back to the optical receiver 184 within the console 110 (see [link]). Figure 1 Based on the type and degree of strain (e.g., compression or tension) sensed on the core fiber 3402 at the first region 3851, the first sensor 380... 21 The characteristics of the reflected light signal 152 are altered. These altered characteristics correspond to a wavelength shift in the reflected light signal 152 that is subjected to a strain type (e.g., compression or tension) and strain degree. The residual spectrum 157 of the incident light 155 continues to propagate through the core fiber 3402 to the distal end 235 of the conduit 130. The residual spectrum 157 of the incident light 155 may encounter another sensor 380. 22 …or 380 2M Among them, these sensors 380 22 …or 380 2M Each of them is manufactured to reflect light with a specific spectral width. Similarly, reflected light signals with different spectral widths are returned from the core fiber 3402.

[0048] As an illustrative example, where a specific region of the conduit 120 is undergoing a change in angular orientation (e.g., bending of the conduit 130), the portion of the second outer core fiber 3402 located at the first measurement region 3851 can be subjected to tension (normal strain; force applied to increase length). As a result, upon receiving incident light 155, the sensor 380 located at the first region 3851... 21 The reflected light 152 will return with increased attenuation (e.g., the frequency of the reflected light signal 152 is higher than the frequency of the incident light 155). Therefore, the stretch applied to the second outer core fiber 3402 causes a shift (increase) in the wavelength of the reflected light, and the amount of wavelength shift is related to the amount of stretch applied to the second outer core fiber 3402.

[0049] Similarly, when a specific region of the catheter undergoes a change in angular orientation, a portion of the fourth outer core fiber 3404, also located in the first measurement region 3851, can undergo compression (negative strain; applying force to shorten its length). As a result, upon receiving incident light 155, the sensor 380 located in the first region 3851... 41The reflected light 152 will return with reduced attenuation (e.g., the frequency of the reflected light signal 152 is lower than the frequency of the incident light 155). Therefore, the stretch applied to the fourth outer core fiber 3404 causes a shift (reduction) in the wavelength of the reflected light, and the amount of wavelength shift propagated on the reflected light signal 152 is related to the amount of compression applied to the fourth outer core fiber 3404.

[0050] Given the above, and considering the spatially separated microcavities 3301-330 N The longitudinal position within the fiber, and the different strains, affect multiple core fibers 3401-340 differently. N Along each core fiber 3401-340 N The degree of wavelength shift encountered by the different sensors in the distributed sensor array can collectively identify the type (e.g., compression, tension) and amount of strain applied to each region of the multiple core fibers. Therefore, multiple reflected light signals corresponding to different spectral widths can provide 3-D shape sensing information to the shape sensing logic 195 within the console 110 to determine how to manipulate each monitored region of the conduit 120, which is generated by the distributed sensor array located at selected regions along the length of the core fibers. As a result, the current physical state of the conduit 120 can be determined based on the analysis of the wavelength shift provided from the core fibers and presented in three dimensions (3-D) on the display 170 of the console 110, as described above.

[0051] Now for reference Figure 4A , showed Figures 3A-3B A perspective view of a first exemplary embodiment of the integrated conduit 130 of the conduit 120. Here, the conduit 120 includes an integrated conduit 130, a diametrically disposed baffle 310, and a plurality of microcavities 3301-3304, which, in this embodiment, are fabricated within the wall 300 of the integrated conduit 130 and within the baffle 310. Specifically, the baffle 310 divides a single cavity formed by the inner surface 305 of the wall 300 of the conduit 130 into a plurality of cavities, namely two cavities 400 and 410 as shown. Here, a first cavity 400 is formed between a first arcuate portion 420 forming the inner surface 305 of the wall 300 of the conduit 130 and a first outer surface 430 of the baffle 310 extending longitudinally within the conduit 130. A second cavity 410 is formed between a second arcuate portion 440 forming the inner surface 305 of the wall 300 of the conduit 130 and a second outer surface 435 of the baffle 310.

[0052] According to one embodiment of the invention, the two cavities 400 and 410 have substantially the same volume. However, the partition 310 need not divide the conduit 130 into two equal cavities. For example, instead of the partition 310 extending vertically (12 o'clock to 6 o'clock) from a forward-facing cross-sectional perspective view of the conduit 130, the partition 310 may extend horizontally (3 o'clock to 9 o'clock), diagonally (1 o'clock to 7 o'clock; 10 o'clock to 4 o'clock), or at an angle (2 o'clock to 10 o'clock). In the latter configuration, each of the cavities 400 and 410 of the conduit 130 will have a different volume.

[0053] Relative to the plurality of microcavities 3301-3304, the first microcavity 3301 is formed within the baffle 310 at or near the cross-sectional center 365 of the conduit 130. In this embodiment, three microcavities 3302-3304 are formed within the wall 300 of the conduit 130. Specifically, the second microcavity 3302 is formed within the wall 300 of the conduit 130, specifically between the inner surface 305 and the outer surface 307 of the first arcuate portion 420 of the wall 300. Similarly, the third microcavity 3303 is also formed within the wall 300 of the conduit 130, specifically between the inner surface and the outer surface 305 / 307 of the second arcuate portion 430 of the wall 300. The fourth microcavity 3304 is also formed within the inner and outer surfaces 305 / 307 of the wall 300 aligned with the baffle 310.

[0054] According to one embodiment of this application, such as Figure 4A As shown, these microcavities 3302-3304 are positioned according to a “top left” (10 o’clock), “top right” (2 o’clock), and “bottom” (6 o’clock) layout as viewed from a front-facing cross-sectional perspective view. Of course, microcavities 3302-3304 can be positioned differently, as long as they are spatially separated along the circumference 370 of the conduit 130 to ensure more robust collection of reflected light signals from the outer core fibers 3402-3404 during installation. For example, two or more microcavities (e.g., microcavities 3302 and 3304) can be positioned in different quadrants along the circumference 370 of the conduit wall 300.

[0055] See now Figure 4B , showed Figure 4AA perspective view of a first illustrative embodiment of the integrated conduit 130 of the conduit 120, wherein core fibers 3401-3404 are mounted within microcavities 3301-3304. According to one embodiment of this application, the dimensions of a second plurality of microcavities 3302-3304 are determined to maintain the corresponding outer core fibers 3402-3404, wherein the diameter of each of the second plurality of microcavities 3302-3304 can be determined to be just larger than the diameter of the outer core fiber 3402-3404. For example, the dimensional difference between the diameter of the single core fiber and the diameter of any one of the microcavities 3301-3304 can be in the range of 0.001 micrometers (µm) to 1000 µm. As a result, the cross-sectional area of ​​the outer core fibers 3402-3404 will be smaller than the cross-sectional area of ​​the corresponding microcavities 3302-3304. A “larger” microcavity (e.g., microcavity 3302) can better isolate the external strain applied to the outer core fiber 3402 from the strain applied directly to the conduit 130 itself. Similarly, the size of the first microcavity 3301 can be determined to hold the central core fiber 3401, wherein the diameter of the first microcavity 3301 can be just larger than the diameter of the central core fiber 3401.

[0056] As an alternative embodiment of this application, the dimensions of one or more of the microcavities 3301-3304 may be defined to have a diameter exceeding the diameter of the corresponding one or more core fibers 3401-3404. However, the dimensions of at least one of the microcavities 3301-3304 are set to permanently hold its corresponding core fiber (e.g., a core fiber held without gap between its transverse surface and the inner wall surface of its corresponding microcavity). As yet another alternative embodiment of this application, the dimensions of all these microcavities 3301-3304 are determined to have a diameter that permanently holds the core fibers 3401-3404.

[0057] See Figure 5 , showed Figures 3A-3BA perspective view of a second illustrative embodiment of the conduit 120. The conduit 120 includes an integrated conduit 130 and a diametrically disposed baffle 500 and a radially disposed baffle 510 extending from the cross-sectional center 365 of the integrated conduit 130. Each of three cavities 520, 522, and 524 is further defined at least partially by the baffle 500. Each of two cavities 522 and 524 is further defined at least partially by the baffle 510. As shown, the baffle 500 divides the internal space within the conduit 130 into a first set of semi-circular cavities, including a first cavity 520. The baffle 510 further divides one of the first set of semi-circular cavities into cavities 522 and 524. Thus, the second cavity 522 can be configured to have approximately the same volume as the third cavity 524, and the first cavity 520 can be configured to have at least twice the volume of the second cavity 522 and the third cavity 524, provided that the longitudinal lengths of cavities 520, 522, and 524 are equal.

[0058] like Figure 5 As further shown, multiple microcavities 3301-3304 are fabricated within the wall 300 and partition 500 of the integrated conduit 130. (The last sentence appears to be incomplete and possibly refers to a different context.) Figure 4A Similarly, a first microcavity 3301 is formed in or near the cross-sectional center 365 of the integrated conduit 130 within the intermediate portion 530 of the partition 500. Three microcavities 3302-3304 are formed within the wall 300 of the integrated conduit 130. Specifically, a second microcavity 3302 is formed within the wall 300 of the conduit 130, specifically between the inner surface 305 and the outer surface 307 of the wall 300 defining the first cavity 520. Similarly, a third microcavity 3303 is also formed within the wall 300 of the conduit 130, for example, in another area between the inner surface 305 and the outer surface 307 of the wall 300. The third microcavity 3303, extending radially from the cross-sectional center 365, is offset from the second microcavity 3302 by approximately ninety degrees (90°) or more radially. The fourth microcavity 3304 may be formed within the inner surface 305 and the outer surface 307 of the wall 300, wherein the fourth microcavity 3304 is aligned with the partition 510. Alternatively, the fourth microcavity 3304 may be formed within the partition 510, which is substantially closer to the inner surface 305 of the wall 300 than the cross-sectional center 365.

[0059] According to this specific embodiment of the application, microcavities 3302-3304 are positioned according to a “lower right” (4 o’clock), “lower left” (8 o’clock), and “top” (12 o’clock) layout as viewed from a front-facing cross-sectional perspective view. Of course, microcavities 3302-3304 can be positioned differently, as long as they are spatially separated along the circumference 370 of the conduit 130 to ensure more robust collection of reflected light signals from these outer core fibers 3402-3404 during installation. For example, as shown, at least two different microcavities (e.g., microcavities 3302 and 3303) can be positioned in different quadrants along the circumference 370 of the conduit wall 300.

[0060] See now Figures 6A-6B This shows the result of Figure 1 This is a flowchart illustrating an operational method for achieving optical three-dimensional shape sensing in components of a medical device monitoring system. Here, the catheter includes at least one septum spanning the diameter of the catheter wall and extending longitudinally to subdivide the wall. A first microlumen is formed in the middle portion of the septum, wherein the first microlumen is coaxial with the central axis of the catheter conduit. The first microlumen is configured to hold a central core fiber. Two or more microlumens, in addition to the first microlumen, are located at different locations circumferentially spaced along the catheter wall. For example, two or more of a second plurality of microlumens may be located in different quadrants along the circumference of the catheter wall.

[0061] Furthermore, each core fiber includes multiple sensors spatially distributed along its length between at least the proximal and distal ends of the conduit. The sensor array is distributed to position sensors at different regions of the core fiber, enabling distributed strain measurements over selected portions or the entire length of the conduit. Distributed measurements can be transmitted via reflected light with different spectral widths (e.g., specific wavelengths or wavelength ranges), the reflected light undergoing specific wavelength shifts based on the type and extent of strain.

[0062] According to one embodiment of this application, as shown in FIG6A, for each core fiber, broadband incident light is provided to propagate through the specific core fiber (box 600). Unless light is emitted, when the incident light reaches a sensor of a distributed sensor array measuring strain on the specific core fiber, light with a predetermined spectral width associated with a first sensor is reflected back to a light receiver within the console (boxes 605-610). Here, the sensor modifies the characteristics of the reflected light signal to identify the type and extent of strain on the specific core fiber measured by the first sensor (boxes 615-620). According to one embodiment of this application, the change in the characteristics of the reflected light signal may represent a change (offset) in the wavelength of the reflected light signal relative to the wavelength of the incident light signal associated with the predetermined spectral width. The sensor returns the reflected light signal through the core fiber, and the remaining spectrum of the incident light continues to propagate through the core fiber toward the distal end of the conduit (boxes 625-630). The remaining spectrum of the incident light may encounter other sensors in the distributed sensor array, each of which will operate as described in boxes 605-630, until the last sensor in the distributed sensor array returns a reflected light signal associated with its assigned spectral width and the remaining spectrum is emitted as illumination.

[0063] Now for reference Figure 6B During operation, multiple reflected light signals are returned to the control console from each of the multiple core fibers located within corresponding microcavities formed within the conduit. Specifically, the light receiver receives the reflected light signals from a distributed sensor array located on the central and outer core fibers and converts the reflected light signals into reflection data, which includes electrical signals represented by the reflected light signals due to wavelength shifts caused by strain (boxes 650-655). The reflection data classification logic is configured to identify which core fibers belong to which reflection data and to separate the reflection data provided by reflected light signals belonging to a specific measurement region (or similar spectral width) into analysis groups (boxes 660-665).

[0064] Each set of analysis data of the reflected light is provided to the shape sensing logic for analysis (box 670). Here, the shape sensing logic compares the wavelength shift at each outer core fiber with the wavelength shift at the central core fiber, which is positioned along the central axis and operates as a curved neutral axis (box 675). Based on the analysis, for all sets of analysis (e.g., reflected light signals from sensors in all or most of the core fibers), the shape sensing logic can determine the shape of the core fibers in three-dimensional space, thereby determining the current physical state of the catheter in three-dimensional space (boxes 680-685).

[0065] Embodiments of the invention may be implemented in other specific forms without departing from the spirit of this application. The described embodiments are considered to be illustrative in all respects only and not restrictive. For example, instead of placing the microcavity within the wall of the integrated conduit, longitudinal beads may be formed along the inner surface of the wall occupying a portion of the cavity, or the microcavity may be formed along the outer surface of the integrated conduit as described above. Therefore, the scope of the embodiments is indicated by the appended claims rather than by the foregoing description. All modifications within the meaning and scope of the equivalents of the claims are included within its scope.

Claims

1. A catheter, comprising: An elongated conduit includes an opening at its distal end, the conduit being formed by an axial wall defining a cavity extending between the proximal and distal ends of the conduit. A partition positioned across the opening of the pipe. A first microcavity is formed in the partition, wherein the first microcavity is formed within the partition along the central axis of the cross-section of the pipe. Multiple microcavities are formed along the circumference of the wall forming the pipe. The first core fiber located within the first microcavity, and Multiple core fibers, each of which is located within a different microcavity of the multiple microcavities. A plurality of sensors are distributed along the longitudinal length of the first core fiber and each of the plurality of core fibers, and each of the plurality of sensors is configured to (i) reflect optical signals with different spectral widths based on the received incident light, and (ii) modify the characteristics of the reflected optical signals to determine the physical state of the conduit, and The comparison between the wavelength shift of the reflected light detected from the plurality of core fibers and the wavelength shift of the reflected light from the first core fiber, which is used as a reference operation, is used to determine the physical state of the catheter.

2. The catheter as claimed in claim 1, wherein, The plurality of microcavities are formed between the outer surface of the wall forming the conduit and the inner surface of the wall, each of the plurality of microcavities extending from the distal end of the conduit to the proximal portion of the conduit.

3. The catheter as claimed in claim 1, wherein, Each of the plurality of sensors constitutes a reflective grating, which is positioned at a different region of a specific core fiber among the plurality of core fibers.

4. The catheter as claimed in claim 1, wherein, The change in the characteristics of the reflected light includes a shift in the wavelength applied to the reflected light signal to identify at least one type of strain.

5. The catheter as claimed in claim 4, wherein, The strain type is compression or tension.

6. The catheter as claimed in claim 1, wherein, Two or more of the plurality of microcavities are formed within the wall of the conduit radiating from the central axis.

7. The catheter of claim 1, wherein (i) a second core fiber of the plurality of core fibers located in a second microcavity of the plurality of microcavities is oriented in a first radial direction relative to the first microcavity and positioned within a first arc segment of the wall; (ii) a third core fiber of the plurality of core fibers located in a third microcavity of the plurality of microcavities is oriented in a second radial direction relative to the first microcavity and positioned within a second arc segment of the wall separated from the first arc segment; and (iii) a fourth core fiber of the plurality of core fibers located in a fourth microcavity of the plurality of microcavities is oriented in a third radial direction relative to the first microcavity and positioned within a third arc segment of the wall separated from both the first and second arc segments.

8. The catheter of claim 1, further comprising a second plurality of core fibers, each located within a microlumen radially distributed from the central axis, wherein each of the second plurality of core fibers is positioned within a different microlumen of the plurality of microlumens.

9. The catheter of claim 8, wherein the second plurality of core fibers includes a second core fiber located within a second microcathode formed coplanar with the first microcathode, a third core fiber located within a third microcathode formed radially from the first microcathode, and a fourth core fiber located within a fourth microcathode formed radially from the first microcathode, the first microcathode forming an obtuse angle between the second microcathode and the third microcathode, the first microcathode forming a first obtuse angle between the second microcathode and the fourth microcathode, and forming a second obtuse angle between the third microcathode and the fourth microcathode.

10. The catheter of claim 1, wherein, At least a second of the plurality of microcavities is formed as a longitudinal bead, the longitudinal bead being a conduit formed on or attached to the outer surface of the axial wall forming the conduit.

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