Patent Publication Number: US-2022233246-A1

Title: Fiber Optic Shape Sensing System Associated With Port Placement

Description:
PRIORITY 
     This application claims the benefit of priority to U.S. Provisional Application No. 63/141,882, filed Jan. 26, 2021, which is incorporated by reference in its entirety into this application. 
    
    
     BACKGROUND 
     In the past, certain intravascular guidance of medical instruments, such as guidewires and catheters for example, have used fluoroscopic methods for tracking tips of the medical instruments and determining whether distal tips are appropriately localized in their target anatomical structures. However, such fluoroscopic methods expose patients and their attending clinicians to harmful X-ray radiation. Moreover, in some cases, the patients are exposed to potentially harmful contrast media needed for the fluoroscopic methods. 
     More recently, electromagnetic tracking systems have been used involving stylets. Generally, electromagnetic tracking systems feature three components: a field generator, a sensor unit and control unit. The field generator uses several coils to generate a position-varying magnetic field, which is used to establish a coordinate space. Attached to the stylet, such as near a distal end (tip) of the stylet for example, the sensor unit includes small coils in which current is induced via the magnetic field. Based on the electrical properties of each coil, the position and orientation of the medical instrument may be determined within the coordinate space. The control unit controls the field generator and captures data from the sensor unit. 
     Although electromagnetic tracking systems avoid line-of-sight reliance in tracking the tip of a stylet while obviating radiation exposure and potentially harmful contrast media associated with fluoroscopic methods, electromagnetic tracking systems are prone to interference. More specifically, since electromagnetic tracking systems depend on the measurement of magnetic fields produced by the field generator, these systems are subject to electromagnetic field interference, which may be caused by the presence of many different types of consumer electronics such as cellular telephones. Additionally, electromagnetic tracking systems are subject to signal drop out, depend on an external sensor, and are defined to a limited depth range. 
     SUMMARY 
     Briefly summarized, embodiments disclosed herein are directed to systems, apparatus and methods for providing tracking information of a distal tip of the medical instrument using optical fiber technology. In some embodiments, the medical instrument includes an optical fiber having one or more optical fiber cores, where each are configured with an array of sensors (reflective gratings), which are spatially distributed over a prescribed length of the core fiber to generally sense external strain and temperature on those regions of the core fiber occupied by the sensor. Each optical fiber core is configured to receive light (e.g., broadband) from a console during advancement through the vasculature of a patient, where the broadband light propagates along at least a partial distance of the optical fiber core toward the distal end. Given that each sensor positioned along the optical fiber core is configured to reflect light of a different, specific spectral width, the array of sensors enables distributed measurements throughout the prescribed length of the medical instrument. These distributed measurements may include wavelength shifts having a correlation with strain and/or temperature experienced by the sensor. 
     The reflected light from the sensors (reflective gratings) within an optical fiber core is returned from the medical instrument for processing by the console. The physical state of the medical instrument may be ascertained based on analytics of the wavelength shifts of the reflected light. For example, the strain caused through bending of the medical instrument and hence angular modification of the optical fiber core, causes different degrees of deformation. The different degrees of deformation alter the shape of the sensors (reflective grating) positioned on the optical fiber core, which may cause variations (shifts) in the wavelength of the reflected light from the sensors positioned on the optical fiber core. The optical fiber core may comprise a single optical fiber, or a plurality of optical fibers (in which case, the optical fiber core is referred to as a “multi-core optical fiber”). 
     As used herein, the term “core fiber,” generally refers to a single optical fiber core disposed within a medical instrument. Thus, discussion of a core fiber refers to single optical fiber core and discussion of a multi-core optical fiber refers to a plurality of core fibers. Various embodiments discussed below to detection of the health (and particularly the damage) that occurs in each of an optical fiber core of medical instrument including (i) a single core fiber, and (ii) a plurality of core fibers. It is noted that in addition to strain altering the shape of a sensor, ambient temperature variations may also alter the shape of a sensor, thereby causing variations (shifts) in the wavelength of the reflected light from the sensors positioned on the optical fiber core. 
     Specific embodiments of the disclosure include utilization of a medical instrument, such as a stylet, featuring a multi-core optical fiber and a conductive medium that collectively operate for tracking placement with a body of a patient of the stylet or another medical instrument (such as a catheter) in which the stylet is disposed. In lieu of a stylet, a guidewire may be utilized. For convenience, embodiments are generally discussed where the optical fiber core is disposed within a stylet; however, the disclosure is not intended to be so limited as the functionality involving detection of the health of an optical fiber core disclosed herein may be implemented regardless of the medical instrument in which the optical fiber core is disposed. In some embodiments, the optical fiber core may be integrated directly into a wall of the catheter. 
     In some embodiments, the optical fiber core of a stylet is configured to return information for use in identifying its physical state (e.g., shape length, shape, and/or form) of (i) a portion of the stylet (e.g., tip, segment of stylet, etc.) or a portion of a catheter inclusive of at least a portion of the stylet (e.g., tip, segment of catheter, etc.) or (ii) the entirety or a substantial portion of the stylet or catheter within the body of a patient (hereinafter, described as the “physical state of the stylet” or the “physical state of the catheter”). According to one embodiment of the disclosure, the returned information may be obtained from reflected light signals of different spectral widths, where each reflected light signal corresponds to a portion of broadband incident light propagating along a core of the multi-core optical fiber (core fiber) that is reflected back over the core fiber by a particular sensor located on the core fiber. One illustrative example of the returned information may pertain to a change in signal characteristics of the reflected light signal returned from the sensor, where wavelength shift is correlated to (mechanical) strain on the core fiber or a detected change in ambient temperature. 
     In some embodiments, the core fiber utilizes a plurality of sensors and each sensor is configured to reflect a different spectral range of the incident light (e.g., different light frequency range). Based on the type and degree of strain asserted on each core fiber, the sensors associated with that core fiber may alter (shift) the wavelength of the reflected light to convey the type and degree of stain on that core fiber at those locations of the stylet occupied by the sensors. The sensors are spatially distributed at various locations of the core fiber between a proximal end and a distal end of the stylet so that shape sensing of the stylet may be conducted based on analytics of the wavelength shifts. Herein, the shape sensing functionality is paired with the ability to simultaneously pass an electrical signal through the same member (stylet) through conductive medium included as part of the stylet. 
     Similarly, the sensors may alter (shift) the wavelength of the reflected light to convey sensed variations in ambient temperature. The alterations in response to detected variations in ambient temperature thereby provide for a temperature sensing functionality. 
     More specifically, in some embodiments each core fiber of the multi-core optical fiber is configured with an array of sensors, which are spatially distributed over a prescribed length of the core fiber to generally sense external strain on or variations in ambient temperature proximate those regions of the core fiber occupied by the sensor. Given that each sensor positioned along the same core fiber is configured to reflect light of a different, specific spectral width, the array of sensors enables distributed measurements throughout the prescribed length of the multi-core optical fiber. These distributed measurements may include wavelength shifts having a correlation with strain experienced and/or temperature variations detected by the sensor. 
     In more detail, each sensor may operate as a reflective grating such as a fiber Bragg grating (FBG), namely an intrinsic sensor corresponding to a permanent, periodic refractive index change inscribed into the core fiber. Stated differently, the sensor operates as a light reflective mirror for a specific spectral width (e.g., a specific wavelength or specific range of wavelengths). As a result, as broadband incident light is supplied by an optical light source and propagates through a particular core fiber, upon reaching a first sensor of the distributed array of sensors for that core fiber, light of a prescribed spectral width associated with the first sensor is reflected back to an optical receiver within a console, including a display and the optical light source. The remaining spectrum of the incident light continues propagation through the core fiber toward a distal end of the stylet. The remaining spectrum of the incident light may encounter other sensors from the distributed array of sensors, where each of these sensors is fabricated to reflect light with different specific spectral widths to provide distributed measurements, as described above. 
     During operation, multiple light reflections (also referred to as “reflected light signals”) are returned to the console from each of the plurality of core fibers of the multi-core optical fiber. Each reflected light signal may be uniquely associated with a different spectral width. Information associated with the reflected light signals may be used to determine a three-dimensional representation of the physical state of the stylet within the body of a patient through detection of strain in response to emitted incident light. Herein, the core fibers are spatially separated with the cladding of the multi-mode optical fiber and each core fiber is configured to separately return light of different spectral widths (e.g., specific light wavelength or a range of light wavelengths) reflected from the distributed array of sensors fabricated in each of the core fibers. 
     During vasculature insertion and advancement of the catheter, the clinician may rely on the console to visualize a current physical state (e.g., shape) of a catheter guided by the stylet to avoid potential path deviations. As the periphery core fibers reside at spatially different locations within the cladding of the multi-mode optical fiber, changes in angular orientation (such as bending with respect to the center core fiber, etc.) of the stylet imposes different types (e.g., compression or tension) and degrees of strain on each of the periphery core fibers as well as the center core fiber. The different types and/or degree of strain may cause the sensors of the core fibers to apply different wavelength shifts, which can be measured to extrapolate the physical state of the stylet (catheter). 
     Additionally, in some embodiments, a medical instrument to be inserted is an implantable medical instrument, such as an implantable catheter that is configured to couple with a port. A second medical instrument that is optically-enabled may be utilized to provide a clinician with a graphical display of the advancement of the implantable medical instrument during the insertion operation. For instance, the second medical instrument may be an optically-enabled stylet that is inserted within the implantable catheter for the insertion operation. Thus, as the insertion operation progresses, incident light signals are provided to the optically-enabled stylet and reflected light signals are returned to a console for analysis. The analysis of the reflect light signals may enable a determination of a shape, positioning, orientation, etc., of the stylet, and consequently, of the implantable catheter. A graphic may then be rendered illustrating the progress of the advancement of the stylet and/or the implantable catheter, optionally as an overlay on a graphic of a patient body. Thus, the clinician may visualize the advancement of the implantable catheter. 
     Further, as positioning of a properly implanted catheter is generally known, a console may have stored thereon, or access to, desired placements of an implantable catheter (e.g., the desired shape and positioning) that may be utilized in analyses performed by logic of the console to determine a progress and/or an accuracy of the insertion operation as compared to the selected desired placement. In some embodiments, machine-learning techniques may be utilized to determine the progress and/or accuracy. 
     Herein, some embodiments disclose a medical instrument system for inserting a first medical instrument within a patient body, the system including the first medical instrument, wherein the first medical instrument is an implantable medical instrument, a second medical instrument comprising an optical fiber having one or more of core fibers and a console including one or more processors and a non-transitory computer-readable medium having stored thereon logic. The logic, when executed by the one or more processors, causes operations including providing an incident light signal to the optical fiber, receiving reflected light signals of different spectral widths of the incident light by the optical fiber, processing the reflected light signals associated with the optical fiber, and determining (i) a shape of the second medical instrument within the patient body, and (ii) a shape of the first medical instrument within the patient body based on the shape of the second medical instrument, and causing rendering of a graphical display of at least one of the shape of either of the first medical instrument or the second medical instrument within the patient body. 
     In some embodiments, each of the one or more core fibers includes a plurality of sensors distributed along a longitudinal length of a corresponding core fiber and each sensor of the plurality of sensors is configured to (i) reflect a light signal of a different spectral width based on received incident light, and (ii) change a characteristic of the reflected light signal for use in determining a physical state of the optical fiber. In some embodiments, the optical fiber is a single-core optical fiber, and wherein the incident light is provided in pulses. In some embodiments, the optical fiber is a multi-core optical fiber including a plurality of core fibers. 
     In some embodiments, the logic, when executed by the one or more processors, causes further operations including receiving user input corresponding to selection of a desired placement of the first medical instrument within the patient body. In some embodiments, the logic, when executed by the one or more processors, causes further operations including causing rendering of a graphical representation of the selected desired placement of the first medical instrument within the patient body. In some embodiments, the graphical display of the at least one of the location of the distal tip of either of the first medical instrument or the second medical instrument within the patient body is rendered as an overlay on the rendering of the graphical representation of the selected desired placement of the first medical instrument. In some embodiments, a graphical representation of the selected desired placement of the first medical instrument is displayed as an overlay to a graphical representation of a template patient body. 
     In some embodiments, the logic, when executed by the one or more processors, causes further operations including causing rendering of an additional graphic that displays one of a completion progress of insertion of the first medical instrument in view of the selected desired placement, an insertion accuracy of the insertion of the first medical instrument in view of the selected desired placement, or a length of the first medical instrument that is disposed within the patient body. In some embodiments, the completion progress is determined through machine-learning. In some embodiments, the insertion progress is determined through machine-learning. In some embodiments, the second medical instrument is one of an introducer wire, a guidewire, a stylet, or a catheter with the optical fiber inlayed into one or more walls of the catheter. In some embodiments, the first medical instrument is an implantable catheter configured to couple with an implantable port. In some embodiments, the logic, when executed by the one or more processors, causes further operations including determining (iii) at least a location of a distal tip of the second medical instrument within the patient body, and (iv) at least a location of the first medical instrument within the patient body based on the location of the distal tip of the second medical instrument. 
     Herein, some embodiments disclose a method for placing a medical instrument into a body of a patient, the method includes providing an incident light signal to the optical fiber, receiving reflected light signals of different spectral widths of the incident light by the optical fiber, processing the reflected light signals associated with the optical fiber, and determining (i) a shape of the second medical instrument within the patient body, and (ii) a shape of the first medical instrument within the patient body based on the location of the distal tip of the second medical instrument, and causing rendering of a graphical display of at least one of the shape of either of the first medical instrument or the second medical instrument within the patient body. 
     In some embodiments, each of the one or more core fibers includes a plurality of sensors distributed along a longitudinal length of a corresponding core fiber and each sensor of the plurality of sensors is configured to (i) reflect a light signal of a different spectral width based on received incident light, and (ii) change a characteristic of the reflected light signal for use in determining a physical state of the optical fiber. In some embodiments, the optical fiber is a single-core optical fiber, and wherein the incident light is provided in pulses. In some embodiments, the optical fiber is a multi-core optical fiber including a plurality of core fibers. 
     In some embodiments, the method includes further operations of receiving user input corresponding to selection of a desired placement of the first medical instrument within the patient body. In some embodiments, the method includes further operations of causing rendering of a graphical representation of the selected desired placement of the first medical instrument within the patient body. In some embodiments, the graphical display of the at least one of the location of the distal tip of either of the first medical instrument or the second medical instrument within the patient body is rendered as an overlay on the rendering of the graphical representation of the selected desired placement of the first medical instrument. In some embodiments, a graphical representation of the selected desired placement of the first medical instrument is displayed as an overlay to a graphical representation of a template patient body. 
     In some embodiments, the method includes further operations of causing rendering of an additional graphic that displays one of a completion progress of insertion of the first medical instrument in view of the selected desired placement, an insertion accuracy of the insertion of the first medical instrument in view of the selected desired placement, or a length of the first medical instrument that is disposed within the patient body. In some embodiments, the completion progress is determined through machine-learning. In some embodiments, the insertion progress is determined through machine-learning. In some embodiments, the second medical instrument is one of an introducer wire, a guidewire, a stylet, or a catheter with the optical fiber inlayed into one or more walls of the catheter. In some embodiments, the first medical instrument is an implantable catheter configured to couple with an implantable port. 
     In some embodiments, the method includes further operations of determining (iii) at least a location of a distal tip of the second medical instrument within the patient body, and (iv) at least a location of the first medical instrument within the patient body based on the location of the distal tip of the second medical instrument. 
     These and other features of the concepts provided herein will become more apparent to those of skill in the art in view of the accompanying drawings and following description, which disclose particular embodiments of such concepts in greater detail. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the disclosure are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which like references indicate similar elements and in which: 
         FIG. 1A  is an illustrative embodiment of a medical instrument monitoring system including a medical instrument with optic shape sensing and fiber optic-based oximetry capabilities in accordance with some embodiments; 
         FIG. 1B  is an alternative illustrative embodiment of the medical instrument monitoring system  100  in accordance with some embodiments; 
         FIG. 2  is an exemplary embodiment of a structure of a section of the multi-core optical fiber included within the stylet  120  of  FIG. 1A  in accordance with some embodiments; 
         FIG. 3A  is a first exemplary embodiment of the stylet of  FIG. 1A  supporting both an optical and electrical signaling in accordance with some embodiments; 
         FIG. 3B  is a cross sectional view of the stylet of  FIG. 3A  in accordance with some embodiments; 
         FIG. 4A  is a second exemplary embodiment of the stylet of  FIG. 1B  in accordance with some embodiments; 
         FIG. 4B  is a cross sectional view of the stylet of  FIG. 4A  in accordance with some embodiments; 
         FIG. 5A  is an elevation view of a first illustrative embodiment of a catheter including integrated tubing, a diametrically disposed septum, and micro-lumens formed within the tubing and septum in accordance with some embodiments; 
         FIG. 5B  is a perspective view of the first illustrative embodiment of the catheter of  FIG. 5A  including core fibers installed within the micro-lumens in accordance with some embodiments; 
         FIGS. 6A-6B  are flowcharts of the methods of operations conducted by the medical instrument monitoring system of  FIGS. 1A-1B  to achieve optic 3D shape sensing in accordance with some embodiments; 
         FIG. 7  is an exemplary embodiment of the medical instrument monitoring system of  FIGS. 1A-1B  during operation and insertion of the catheter into a patient in accordance with some embodiments; 
         FIG. 8A  is an exemplary embodiment of the medical instrument monitoring system of  FIGS. 1A-1B  during operation including insertion of an implantable port catheter into a patient in accordance with some embodiments; 
         FIG. 8B  is an illustration of an implantable port catheter inserted through an operation as illustrated in  FIG. 8A  in accordance with some embodiments; 
         FIG. 9A  is an exemplary embodiment of the medical instrument monitoring system of  FIG. 1A  with the console displaying an anticipated shape of an implantable port catheter to be inserted into a patient in accordance with some embodiments; 
         FIG. 9B  illustrates the configuration of  FIG. 9A  with the console displaying the anticipated shape of an implantable port catheter to be inserted and an overlay of the implantable port catheter during insertion of a patient in accordance with some embodiments; 
         FIG. 9C  illustrates the configuration of  FIGS. 9A-9B  with the console displaying the anticipated shape of an implantable port catheter to be inserted and an overlay of the implantable port catheter fully inserted of a patient in accordance with some embodiments; 
         FIG. 10  is an exemplary embodiment of the medical instrument monitoring system of  FIG. 1A  with the console displaying the anticipated shape of an implantable port catheter to be inserted and an overlay of the implantable port catheter off-trajectory during insertion of a patient in accordance with some embodiments; and 
         FIGS. 11A-11B  illustrate a flowchart of an exemplary methodology of inserting an implantable port catheter into a patient vasculature in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Before some particular embodiments are disclosed in greater detail, it should be understood that the particular embodiments disclosed herein do not limit the scope of the concepts provided herein. It should also be understood that a particular embodiment disclosed herein can have features that can be readily separated from the particular embodiment and optionally combined with or substituted for features of any of a number of other embodiments disclosed herein. 
     Regarding terms used herein, it should also be understood the terms are for the purpose of describing some particular embodiments, and the terms 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 features or steps in a group of features or steps, and do not supply a serial or numerical limitation. For example, “first,” “second,” and “third” features or steps need not necessarily appear in that order, and the particular embodiments including such features or steps need not necessarily be limited to the three features or steps. Labels such as “left,” “right,” “top,” “bottom,” “front,” “back,” and the like are used for convenience and are not intended to imply, for example, any particular fixed location, orientation, or direction. Instead, such labels are used to reflect, for example, relative location, orientation, or directions. Singular forms of “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. 
     With respect to “proximal,” a “proximal portion” or a “proximal end portion” of, for example, a probe disclosed herein includes a portion of the probe intended to be near a clinician when the probe is used on a patient. Likewise, a “proximal length” of, for example, the probe includes a length of the probe intended to be near the clinician when the probe is used on the patient. A “proximal end” of, for example, the probe includes an end of the probe intended to be near the clinician when the probe is used on the patient. The proximal portion, the proximal end portion, or the proximal length of the probe can include the proximal end of the probe; however, the proximal portion, the proximal end portion, or the proximal length of the probe need not include the proximal end of the probe. That is, unless context suggests otherwise, the proximal portion, the proximal end portion, or the proximal length of the probe is not a terminal portion or terminal length of the probe. 
     With respect to “distal,” a “distal portion” or a “distal end portion” of, for example, a probe disclosed herein includes a portion of the probe intended to be near or in a patient when the probe is used on the patient. Likewise, a “distal length” of, for example, the probe includes a length of the probe intended to be near or in the patient when the probe is used on the patient. A “distal end” of, for example, the probe includes an end of the probe intended to be near or in the patient when the probe is used on the patient. The distal portion, the distal end portion, or the distal length of the probe can include the distal end of the probe; however, the distal portion, the distal end portion, or the distal length of the probe need not include the distal end of the probe. That is, unless context suggests otherwise, the distal portion, the distal end portion, or the distal length of the probe is not a terminal portion or terminal length of the probe. 
     The term “logic” may be representative of hardware, firmware or software that is configured to perform one or more functions. As hardware, the term logic may refer to or include circuitry having data processing and/or storage functionality. Examples of such circuitry may include, but are not limited or restricted to a hardware processor (e.g., microprocessor, one or more processor cores, a digital signal processor, a programmable gate array, a microcontroller, an application specific integrated circuit “ASIC”, etc.), a semiconductor memory, or combinatorial elements. 
     Additionally, or in the alternative, the term logic may refer to or include software such as one or more processes, one or more instances, Application Programming Interface(s) (API), subroutine(s), function(s), applet(s), servlet(s), routine(s), source code, object code, shared library/dynamic link library (dll), or even one or more instructions. This software may be stored in any type of a suitable non-transitory storage medium, or transitory storage medium (e.g., electrical, optical, acoustical or other form of propagated signals such as carrier waves, infrared signals, or digital signals). Examples of a non-transitory storage medium may include, but are not limited or restricted to a programmable circuit; non-persistent storage such as volatile memory (e.g., any type of random access memory “RAM”); or persistent storage such as non-volatile memory (e.g., read-only memory “ROM”, power-backed RAM, flash memory, phase-change memory, etc.), a solid-state drive, hard disk drive, an optical disc drive, or a portable memory device. As firmware, the logic may be stored in persistent storage. 
     Referring to  FIG. 1A , an illustrative embodiment of a medical instrument monitoring system including a medical instrument with optic shape sensing and fiber optic-based oximetry capabilities is shown in accordance with some embodiments. As shown, the system  100  generally includes a console  110  and a stylet assembly  119  communicatively coupled to the console  110 . For this embodiment, the stylet assembly  119  includes an elongate probe (e.g., stylet)  120  on its distal end  122  and a console connector  133  on its proximal end  124 . The console connector  133  enables the stylet assembly  119  to be operably connected to the console  110  via an interconnect  145  including one or more optical fibers  147  (hereinafter, “optical fiber(s)”) and a conductive medium terminated by a single optical/electric connector  146  (or terminated by dual connectors. Herein, the connector  146  is configured to engage (mate) with the console connector  133  to allow for the propagation of light between the console  110  and the stylet assembly  119  as well as the propagation of electrical signals from the stylet  120  to the console  110 . 
     An exemplary implementation of the console  110  includes a processor  160 , a memory  165 , a display  170  and optical logic  180 , although it is appreciated that the console  110  can take one of a variety of forms and may include additional components (e.g., power supplies, ports, interfaces, etc.) that are not directed to aspects of the disclosure. An illustrative example of the console  110  is illustrated in U.S. Publication No. 2019/0237902, the entire contents of which are incorporated by reference herein. The processor  160 , with access to the memory  165  (e.g., non-volatile memory or non-transitory, computer-readable medium), is included to control functionality of the console  110  during operation. As shown, the display  170  may be a liquid crystal diode (LCD) display integrated into the console  110  and employed as a user interface to display information to the clinician, especially during a catheter placement procedure (e.g., cardiac catheterization). In another embodiment, the display  170  may be separate from the console  110 . Although not shown, a user interface is configured to provide user control of the console  110 . 
     For both of these embodiments, the content depicted by the display  170  may change according to which mode the stylet  120  is configured to operate: optical, TLS, ECG, or another modality. In TLS mode, the content rendered by the display  170  may constitute a two-dimensional (2D) or three-dimensional (3D) representation of the physical state (e.g., length, shape, form, and/or orientation) of the stylet  120  computed from characteristics of reflected light signals  150  returned to the console  110 . The reflected light signals  150  constitute light of a specific spectral width of broadband incident light  155  reflected back to the console  110 . According to one embodiment of the disclosure, the reflected light signals  150  may pertain to various discrete portions (e.g., specific spectral widths) of broadband incident light  155  transmitted from and sourced by the optical logic  180 , as described below 
     According to one embodiment of the disclosure, an activation control  126 , included on the stylet assembly  119 , may be used to set the stylet  120  into a desired operating mode and selectively alter operability of the display  170  by the clinician to assist in medical device placement. For example, based on the modality of the stylet  120 , the display  170  of the console  110  can be employed for optical modality-based guidance during catheter advancement through the vasculature or TLS modality to determine the physical state (e.g., length, form, shape, orientation, etc.) of the stylet  120 . In one embodiment, information from multiple modes, such as optical, TLS or ECG for example, may be displayed concurrently (e.g., at least partially overlapping in time). 
     Referring still to  FIG. 1A , the optical logic  180  is configured to support operability of the stylet assembly  119  and enable the return of information to the console  110 , which may be used to determine the physical state associated with the stylet  120  along with monitored electrical signals such as ECG signaling via an electrical signaling logic  181  that supports receipt and processing of the received electrical signals from the stylet  120  (e.g., ports, analog-to-digital conversion logic, etc.). The physical state of the stylet  120  may be based on changes in characteristics of the reflected light signals  150  received at the console  110  from the stylet  120 . The characteristics may include shifts in wavelength caused by strain on certain regions of the core fibers integrated within an optical fiber core  135  positioned within or operating as the stylet  120 , as shown below. As discussed herein, the optical fiber core  135  may be comprised of core fibers  137   1 - 137   M  (M=1 for a single core, and M≥2 for a multi-core), where the core fibers  137   1 - 137   M  may collectively be referred to as core fiber(s)  137 . Unless otherwise specified or the instant embodiment requires an alternative interpretation, embodiments discussed herein will refer to a multi-core optical fiber  135 . From information associated with the reflected light signals  150 , the console  110  may determine (through computation or extrapolation of the wavelength shifts) the physical state of the stylet  120 , and also that of a catheter  195  configured to receive the stylet  120 . 
     According to one embodiment of the disclosure, as shown in  FIG. 1A , the optical logic  180  may include a light source  182  and an optical receiver  184 . The light source  182  is configured to transmit the incident light  155  (e.g., broadband) for propagation over the optical fiber(s)  147  included in the interconnect  145 , which are optically connected to the multi-core optical fiber core  135  within the stylet  120 . In one embodiment, the light source  182  is a tunable swept laser, although other suitable light sources can also be employed in addition to a laser, including semi-coherent light sources, LED light sources, etc. 
     The optical receiver  184  is configured to: (i) receive returned optical signals, namely reflected light signals  150  received from optical fiber-based reflective gratings (sensors) fabricated within each core fiber of the multi-core optical fiber  135  deployed within the stylet  120 , and (ii) translate the reflected light signals  150  into reflection data  192 , namely data in the form of electrical signals representative of the reflected light signals including wavelength shifts caused by strain. The reflected light signals  150  associated with different spectral widths may include reflected light signals  151  provided from sensors positioned in the center core fiber (reference) of the multi-core optical fiber  135  and reflected light signals  152  provided from sensors positioned in the periphery core fibers of the multi-core optical fiber  135 , as described below. Herein, the optical receiver  184  may be implemented as a photodetector, such as a positive-intrinsic-negative “PIN” photodiode, avalanche photodiode, or the like. 
     As shown, both the light source  182  and the optical receiver  184  are operably connected to the processor  160 , which governs their operation. Also, the optical receiver  184  is operably coupled to provide the reflection data  192  to the memory  165  for storage and processing by reflection data classification logic  190 . The reflection data classification logic  190  may be configured to: (i) identify which core fibers pertain to which of the received reflection data  192  and (ii) segregate the reflection data  192  provided from reflected light signals  150  pertaining to similar regions of the stylet  120  or spectral widths into analysis groups. The reflection data for each analysis group is made available to shape sensing logic  194  for analytics. 
     According to one embodiment of the disclosure, the shape sensing logic  194  is configured to compare wavelength shifts measured by sensors deployed in each periphery core fiber at the same measurement region of the stylet  120  (or same spectral width) to the wavelength shift at a center core fiber of the multi-core optical fiber  135  positioned along central axis and operating as a neutral axis of bending. From these analytics, the shape sensing logic  194  may determine the shape the core fibers have taken in 3D space and may further determine the current physical state of the catheter  195  in 3D space for rendering on the display  170 . 
     According to one embodiment of the disclosure, the shape sensing logic  194  may generate a rendering of the current physical state of the stylet  120  (and potentially the catheter  195 ), based on heuristics or run-time analytics. For example, the shape sensing logic  194  may be configured in accordance with machine-learning techniques to access a data store (library) with pre-stored data (e.g., images, etc.) pertaining to different regions of the stylet  120  (or catheter  195 ) in which reflected light from core fibers have previously experienced similar or identical wavelength shifts. From the pre-stored data, the current physical state of the stylet  120  (or catheter  195 ) may be rendered. Alternatively, as another example, the shape sensing logic  194  may be configured to determine, during run-time, changes in the physical state of each region of the multi-core optical fiber  135  based on at least: (i) resultant wavelength shifts experienced by different core fibers within the optical fiber  135 , and (ii) the relationship of these wavelength shifts generated by sensors positioned along different periphery core fibers at the same cross-sectional region of the multi-core optical fiber  135  to the wavelength shift generated by a sensor of the center core fiber at the same cross-sectional region. It is contemplated that other processes and procedures may be performed to utilize the wavelength shifts as measured by sensors along each of the core fibers within the multi-core optical fiber  135  to render appropriate changes in the physical state of the stylet  120  (and/or catheter  195 ), especially to enable guidance of the stylet  120 , when positioned at a distal tip of the catheter  195 , within the vasculature of the patient and at a desired destination within the body. 
     The console  110  may further include electrical signaling logic  181 , which is positioned to receive one or more electrical signals from the stylet  120 . The stylet  120  is configured to support both optical connectivity as well as electrical connectivity. The electrical signaling logic  181  receives the electrical signals (e.g., ECG signals) from the stylet  120  via the conductive medium. The electrical signals may be processed by electrical signal logic  196 , executed by the processor  160 , to determine ECG waveforms for display. 
     Referring to  FIG. 1B , an alternative exemplary embodiment of a medical instrument monitoring system  100  is shown. Herein, the medical instrument monitoring system  100  features a console  110  and a medical instrument  130  communicatively coupled to the console  110 . For this embodiment, the medical instrument  130  corresponds to a catheter, which features an integrated tubing with two or more lumen extending between a proximal end  131  and a distal end  132  of the integrated tubing. The integrated tubing (sometimes referred to as “catheter tubing”) is in communication with one or more extension legs  140  via a bifurcation hub  142 . An optical-based catheter connector  144  may be included on a proximal end of at least one of the extension legs  140  to enable the catheter  130  to operably connect to the console  110  via an interconnect  145  or another suitable component. Herein, the interconnect  145  may include a connector  146  that, when coupled to the optical-based catheter connector  144 , establishes optical connectivity between one or more optical fibers  147  (hereinafter, “optical fiber(s)”) included as part of the interconnect  145  and core fibers  137  deployed within the catheter  130  and integrated into the tubing. Alternatively, a different combination of connectors, including one or more adapters, may be used to optically connect the optical fiber(s)  147  to the core fibers  137  within the catheter  130 . The core fibers  137  deployed within the catheter  130  as illustrated in  FIG. 1B  include the same characteristics and perform the same functionalities as the core fibers  137  deployed within the stylet  120  of  FIG. 1A . 
     The optical logic  180  is configured to support graphical rendering of the catheter  130 , most notably the integrated tubing of the catheter  130 , based on characteristics of the reflected light signals  150  received from the catheter  130 . The characteristics may include shifts in wavelength caused by strain on certain regions of the core fibers  137  integrated within (or along) a wall of the integrated tubing, which may be used to determine (through computation or extrapolation of the wavelength shifts) the physical state of the catheter  130 , notably its integrated tubing or a portion of the integrated tubing such as a tip or distal end of the tubing to read fluctuations (real-time movement) of the tip (or distal end). 
     More specifically, the optical logic  180  includes a light source  182 . The light source  182  is configured to transmit the broadband incident light  155  for propagation over the optical fiber(s)  147  included in the interconnect  145 , which are optically connected to multiple core fibers  137  within the catheter tubing. Herein, the optical receiver  184  is configured to: (i) receive returned optical signals, namely reflected light signals  150  received from optical fiber-based reflective gratings (sensors) fabricated within each of the core fibers  137  deployed within the catheter  130 , and (ii) translate the reflected light signals  150  into reflection data  192 , namely data in the form of electrical signals representative of the reflected light signals including wavelength shifts caused by strain. The reflected light signals  150  associated with different spectral widths include reflected light signals  151  provided from sensors positioned in the center core fiber (reference) of the catheter  130  and reflected light signals  152  provided from sensors positioned in the outer core fibers of the catheter  130 , as described below. 
     As noted above, the shape sensing logic  194  is configured to compare wavelength shifts measured by sensors deployed in each outer core fiber at the same measurement region of the catheter (or same spectral width) to the wavelength shift at the center core fiber positioned along central axis and operating as a neutral axis of bending. From these analytics, the shape sensing logic  190  may determine the shape the core fibers have taken in 3D space and may further determine the current physical state of the catheter  130  in 3D space for rendering on the display  170 . 
     According to one embodiment of the disclosure, the shape sensing logic  194  may generate a rendering of the current physical state of the catheter  130 , especially the integrated tubing, based on heuristics or run-time analytics. For example, the shape sensing logic  194  may be configured in accordance with machine-learning techniques to access a data store (library) with pre-stored data (e.g., images, etc.) pertaining to different regions of the catheter  130  in which the core fibers  137  experienced similar or identical wavelength shifts. From the pre-stored data, the current physical state of the catheter  130  may be rendered. Alternatively, as another example, the shape sensing logic  194  may be configured to determine, during run-time, changes in the physical state of each region of the catheter  130 , notably the tubing, based on at least (i) resultant wavelength shifts experienced by the core fibers  137  and (ii) the relationship of these wavelength shifts generated by sensors positioned along different outer core fibers at the same cross-sectional region of the catheter  130  to the wavelength shift generated by a sensor of the center core fiber at the same cross-sectional region. It is contemplated that other processes and procedures may be performed to utilize the wavelength shifts as measured by sensors along each of the core fibers  137  to render appropriate changes in the physical state of the catheter  130 . 
     Referring to  FIG. 2 , an exemplary embodiment of a structure of a section of the multi-core optical fiber included within the stylet  120  of  FIG. 1A  is shown in accordance with some embodiments. The multi-core optical fiber section  200  of the multi-core optical fiber  135  depicts certain core fibers  137   1 - 137   M  (M≥2, M=4 as shown, see  FIG. 3A ) along with the spatial relationship between sensors (e.g., reflective gratings)  210   11 - 210   NM  (N≥2; M≥2) present within the core fibers  137   1 - 137   M , respectively. As noted above, the core fibers  137   1 - 137   M  may be collectively referred to as “the core fibers  137 .” 
     As shown, the section  200  is subdivided into a plurality of cross-sectional regions  220   1 - 220   N , where each cross-sectional region  220   1 - 220   N  corresponds to reflective gratings  210   11 - 210   14  . . .  210   N1 - 210   N4 . Some or all of the cross-sectional regions  220   1  . . .  220   N  may be static (e.g., prescribed length) or may be dynamic (e.g., vary in size among the regions  220   1  . . .  220   N ). A first core fiber  137   1  is positioned substantially along a center (neutral) axis  230  while core fiber  137   2  may be oriented within the cladding of the multi-core optical fiber  135 , from a cross-sectional, front-facing perspective, to be position on “top” the first core fiber  137   1 . In this deployment, the core fibers  137   3  and  137   4  may be positioned “bottom left” and “bottom right” of the first core fiber  137   1 . As examples,  FIGS. 3A-4B  provides illustrations of such. 
     Referencing the first core fiber  137   1  as an illustrative example, when the stylet  120  is operative, each of the reflective gratings  210   1 - 210   N  reflects light for a different spectral width. As shown, each of the gratings  210   11 -210 Ni  (1≤i≤M) is associated with a different, specific spectral width, which would be represented by different center frequencies of f 1  . . . f N , where neighboring spectral widths reflected by neighboring gratings are non-overlapping according to one embodiment of the disclosure. 
     Herein, positioned in different core fibers  137   2 - 137   3  but along at the same cross-sectional regions  220 - 220   N  of the multi-core optical fiber  135 , the gratings  210   12 - 210   N2  and  210   13 - 210   N3  are configured to reflect incoming light at same (or substantially similar) center frequency. As a result, the reflected light returns information that allows for a determination of the physical state of the optical fibers  137  (and the stylet  120 ) based on wavelength shifts measured from the returned, reflected light. In particular, strain (e.g., compression or tension) applied to the multi-core optical fiber  135  (e.g., at least core fibers  137   2 - 137   3 ) results in wavelength shifts associated with the returned, reflected light. Based on different locations, the core fibers  137   1 - 137   4  experience different types and degree of strain based on angular path changes as the stylet  120  advances in the patient. 
     For example, with respect to the multi-core optical fiber section  200  of  FIG. 2 , in response to angular (e.g., radial) movement of the stylet  120  is in the left-veering direction, the fourth core fiber  137   4  (see  FIG. 3A ) of the multi-core optical fiber  135  with the shortest radius during movement (e.g., core fiber closest to a direction of angular change) would exhibit compression (e.g., forces to shorten length). At the same time, the third core fiber  137   3  with the longest radius during movement (e.g., core fiber furthest from the direction of angular change) would exhibit tension (e.g., forces to increase length). As these forces are different and unequal, the reflected light from reflective gratings  210   N2  and  210   N3  associated with the core fiber  137   2  and  137   3  will exhibit different changes in wavelength. The differences in wavelength shift of the reflected light signals  150  can be used to extrapolate the physical configuration of the stylet  120  by determining the degrees of wavelength change caused by compression/tension for each of the periphery fibers (e.g., the second core fiber  137   2  and the third core fiber  137   3 ) in comparison to the wavelength of the reference core fiber (e.g., first core fiber  137   1 ) located along the neutral axis  230  of the multi-core optical fiber  135 . These degrees of wavelength change may be used to extrapolate the physical state of the stylet  120 . The reflected light signals  150  are reflected back to the console  110  via individual paths over a particular core fiber  137   1 - 137   M . 
     Referring to  FIG. 3A , a first exemplary embodiment of the stylet of  FIG. 1A  supporting both an optical and electrical signaling is shown in accordance with some embodiments. Herein, the stylet  120  features a centrally located multi-core optical fiber  135 , which includes a cladding  300  and a plurality of core fibers  137   1 - 137   M  (M≥2; M=4) residing within a corresponding plurality of lumens  320   1 - 320   M . While the multi-core optical fiber  135  is illustrated within four (4) core fibers  137   1 - 137   4 , a greater number of core fibers  137   1 - 137   M  (M&gt;4) may be deployed to provide a more detailed three-dimensional sensing of the physical state (e.g., shape, etc.) of the multi-core optical fiber  135  and the stylet  120  deploying the optical fiber  135 . 
     For this embodiment of the disclosure, the multi-core optical fiber  135  is encapsulated within a concentric braided tubing  310  positioned over a low coefficient of friction layer  335 . The braided tubing  310  may feature a “mesh” construction, in which the spacing between the intersecting conductive elements is selected based on the degree of rigidity desired for the stylet  120 , as a greater spacing may provide a lesser rigidity, and thereby, a more pliable stylet  120 . 
     According to this embodiment of the disclosure, as shown in  FIGS. 3A-3B , the core fibers  137   1 - 137   4  include (i) a central core fiber  137   1  and (ii) a plurality of periphery core fibers  137   2 - 137   4 , which are maintained within lumens  320   1 - 320   4  formed in the cladding  300 . According to one embodiment of the disclosure, one or more of the lumen  320   1 - 320   4  may be configured with a diameter sized to be greater than the diameter of the core fibers  137   1 - 137   4 . By avoiding a majority of the surface area of the core fibers  137   1 - 137   4  from being in direct physical contact with a wall surface of the lumens  320   1 - 320   4 , the wavelength changes to the incident light are caused by angular deviations in the multi-core optical fiber  135  thereby reducing influence of compression and tension forces being applied to the walls of the lumens  320   1 - 320   M , not the core fibers  137   1 - 137   M  themselves. 
     As further shown in  FIGS. 3A-3B , the core fibers  137   1 - 137   4  may include central core fiber  137   1  residing within a first lumen  320   1  formed along the first neutral axis  230  and a plurality of core fibers  137   2 - 137   4  residing within lumens  320   2 - 320   4  each formed within different areas of the cladding  300  radiating from the first neutral axis  230 . In general, the core fibers  137   2 - 137   4 , exclusive of the central core fiber  137   1 , may be positioned at different areas within a cross-sectional area  305  of the cladding  300  to provide sufficient separation to enable three-dimensional sensing of the multi-core optical fiber  135  based on changes in wavelength of incident light propagating through the core fibers  137   2 - 137   4  and reflected back to the console for analysis. 
     For example, where the cladding  300  features a circular cross-sectional area  305  as shown in  FIG. 3B , the core fibers  137   2 - 137   4  may be positioned substantially equidistant from each other as measured along a perimeter of the cladding  300 , such as at “top” (12 o&#39;clock), “bottom-left” (8 o&#39;clock) and “bottom-right” (4 o&#39;clock) locations as shown. Hence, in general terms, the core fibers  137   2 - 137   4  may be positioned within different segments of the cross-sectional area  305 . Where the cross-sectional area  305  of the cladding  300  has a distal tip  330  and features a polygon cross-sectional shape (e.g., triangular, square, rectangular, pentagon, hexagon, octagon, etc.), the central core fiber  137   1  may be located at or near a center of the polygon shape, while the remaining core fibers  137   2 - 137   M  may be located proximate to angles between intersecting sides of the polygon shape. 
     Referring still to  FIGS. 3A-3B , operating as the conductive medium for the stylet  120 , the braided tubing  310  provides mechanical integrity to the multi-core optical fiber  135  and operates as a conductive pathway for electrical signals. For example, the braided tubing  310  may be exposed to a distal tip of the stylet  120 . The cladding  300  and the braided tubing  310 , which is positioned concentrically surrounding a circumference of the cladding  300 , are contained within the same insulating layer  350 . The insulating layer  350  may be a sheath or conduit made of protective, insulating (e.g., non-conductive) material that encapsulates both for the cladding  300  and the braided tubing  310 , as shown. 
     Referring to  FIG. 4A , a second exemplary embodiment of the stylet of  FIG. 1B  is shown in accordance with some embodiments. Referring now to  FIG. 4A , a second exemplary embodiment of the stylet  120  of  FIG. 1B  supporting both an optical and electrical signaling is shown. Herein, the stylet  120  features the multi-core optical fiber  135  described above and shown in  FIG. 3A , which includes the cladding  300  and the first plurality of core fibers  137   1 - 137   M  (M≥3; M=4 for embodiment) residing within the corresponding plurality of lumens  320   1 - 320   M . For this embodiment of the disclosure, the multi-core optical fiber  135  includes the central core fiber  137   1  residing within the first lumen  320   1  formed along the first neutral axis  230  and the second plurality of core fibers  137   2 - 137   4  residing within corresponding lumens  320   2 - 320   4  positioned in different segments within the cross-sectional area  305  of the cladding  300 . Herein, the multi-core optical fiber  135  is encapsulated within a conductive tubing  400 . The conductive tubing  400  may feature a “hollow” conductive cylindrical member concentrically encapsulating the multi-core optical fiber  135 . 
     Referring to  FIGS. 4A-4B , operating as a conductive medium for the stylet  120  in the transfer of electrical signals (e.g., ECG signals) to the console, the conductive tubing  400  may be exposed up to a tip  410  of the stylet  120 . For this embodiment of the disclosure, a conductive epoxy  420  (e.g., metal-based epoxy such as a silver epoxy) may be affixed to the tip  410  and similarly joined with a termination/connection point created at a proximal end  430  of the stylet  120 . The cladding  300  and the conductive tubing  400 , which is positioned concentrically surrounding a circumference of the cladding  300 , are contained within the same insulating layer  440 . The insulating layer  440  may be a protective conduit encapsulating both for the cladding  300  and the conductive tubing  400 , as shown. 
     Referring to  FIG. 5A , an elevation view of a first illustrative embodiment of a catheter including integrated tubing, a diametrically disposed septum, and micro-lumens formed within the tubing and septum is shown in accordance with some embodiments. Herein, the catheter  130  includes integrated tubing, the diametrically disposed septum  510 , and the plurality of micro-lumens  530   1 - 530   4  which, for this embodiment, are fabricated to reside within the wall  500  of the integrated tubing of the catheter  130  and within the septum  510 . In particular, the septum  510  separates a single lumen, formed by the inner surface  505  of the wall  500  of the catheter  130 , into multiple lumen, namely two lumens  540  and  545  as shown. Herein, the first lumen  540  is formed between a first arc-shaped portion  535  of the inner surface  505  of the wall  500  forming the catheter  130  and a first outer surface  555  of the septum  510  extending longitudinally within the catheter  130 . The second lumen  545  is formed between a second arc-shaped portion  565  of the inner surface  505  of the wall  500  forming the catheter  130  and a second outer surfaces  560  of the septum  510 . 
     According to one embodiment of the disclosure, the two lumens  540  and  545  have approximately the same volume. However, the septum  510  need not separate the tubing into two equal lumens. For example, instead of the septum  510  extending vertically (12 o&#39;clock to 6 o&#39;clock) from a front-facing, cross-sectional perspective of the tubing, the septum  510  could extend horizontally (3 o&#39;clock to 9 o&#39;clock), diagonally (1 o&#39;clock to 7 o&#39;clock; 10 o&#39;clock to 4 o&#39;clock) or angularly (2 o&#39;clock to 10 o&#39;clock). In the later configuration, each of the lumens  540  and  545  of the catheter  130  would have a different volume. 
     With respect to the plurality of micro-lumens  530   1 - 530   4 , the first micro-lumen  530   1  is fabricated within the septum  510  at or near the cross-sectional center  525  of the integrated tubing. For this embodiment, three micro-lumens  530   2 - 530   4  are fabricated to reside within the wall  500  of the catheter  130 . In particular, a second micro-lumen  530   2  is fabricated within the wall  500  of the catheter  130 , namely between the inner surface  505  and outer surface  507  of the first arc-shaped portion  535  of the wall  500 . Similarly, the third micro-lumen  530   3  is also fabricated within the wall  500  of the catheter  130 , namely between the inner and outer surfaces  505 / 507  of the second arc-shaped portion  555  of the wall  500 . The fourth micro-lumen  530   4  is also fabricated within the inner and outer surfaces  505 / 507  of the wall  500  that are aligned with the septum  510 . 
     According to one embodiment of the disclosure, as shown in  FIG. 5A , the micro-lumens  530   2 - 530   4  are positioned in accordance with a “top-left” (10 o&#39;clock), “top-right” (2 o&#39;clock) and “bottom” (6 o&#39;clock) layout from a front-facing, cross-sectional perspective. Of course, the micro-lumens  530   2 - 530   4  may be positioned differently, provided that the micro-lumens  530   2 - 530   4  are spatially separated along the circumference  520  of the catheter  130  to ensure a more robust collection of reflected light signals from the outer core fibers  570   2 - 570   4  when installed. For example, two or more of micro-lumens (e.g., micro-lumens  530   2  and  530   4 ) may be positioned at different quadrants along the circumference  520  of the catheter wall  500 . 
     Referring to  FIG. 5B , a perspective view of the first illustrative embodiment of the catheter of  FIG. 5A  including core fibers installed within the micro-lumens is shown in accordance with some embodiments. According to one embodiment of the disclosure, the second plurality of micro-lumens  530   2 - 530   4  are sized to retain corresponding outer core fibers  570   2 - 570   4 , where the diameter of each of the second plurality of micro-lumens  530   2 - 530   4  may be sized just larger than the diameters of the outer core fibers  570   2 - 570   4 . The size differences between a diameter of a single core fiber and a diameter of any of the micro-lumen  530   1 - 530   4  may range between 0.001 micrometers (μm) and 1000 μm, for example. As a result, the cross-sectional areas of the outer core fibers  570   2 - 570   4  would be less than the cross-sectional areas of the corresponding micro-lumens  530   2 - 530   4 . A “larger” micro-lumen (e.g., micro-lumen  530   2 ) may better isolate external strain being applied to the outer core fiber  570   2  from strain directly applied to the catheter  130  itself. Similarly, the first micro-lumen  530   1  may be sized to retain the center core fiber  570   1 , where the diameter of the first micro-lumen  530   1  may be sized just larger than the diameter of the center core fiber  570   1 . 
     As an alternative embodiment of the disclosure, one or more of the micro-lumens  530   1 - 530   4  may be sized with a diameter that exceeds the diameter of the corresponding one or more core fibers  570   1 - 570   4 . However, at least one of the micro-lumens  530   1 - 530   4  is sized to fixedly retain their corresponding core fiber (e.g., core fiber retained with no spacing between its lateral surface and the interior wall surface of its corresponding micro-lumen). As yet another alternative embodiment of the disclosure, all the micro-lumens  530   1 - 530   4  are sized with a diameter to fixedly retain the core fibers  570   1 - 570   4 . 
     Referring to  FIGS. 6A-6B , flowcharts of methods of operations conducted by the medical instrument monitoring system of  FIGS. 1A-1B  to achieve optic 3D shape sensing are shown in accordance with some embodiments. Herein, the catheter includes at least one septum spanning across a diameter of the tubing wall and continuing longitudinally to subdivide the tubing wall. The medial portion of the septum is fabricated with a first micro-lumen, where the first micro-lumen is coaxial with the central axis of the catheter tubing. The first micro-lumen is configured to retain a center core fiber. Two or more micro-lumen, other than the first micro-lumen, are positioned at different locations circumferentially spaced along the wall of the catheter tubing. For example, two or more of the second plurality of micro-lumens may be positioned at different quadrants along the circumference of the catheter wall. 
     Furthermore, each core fiber includes a plurality of sensors spatially distributed along its length between at least the proximal and distal ends of the catheter tubing. This array of sensors is distributed to position sensors at different regions of the core fiber to enable distributed measurements of strain throughout the entire length or a selected portion of the catheter tubing. These distributed measurements may be conveyed through reflected light of different spectral widths (e.g., specific wavelength or specific wavelength ranges) that undergoes certain wavelength shifts based on the type and degree of strain. 
     According to one embodiment of the disclosure, as shown in  FIG. 6A , for each core fiber, broadband incident light is supplied to propagate through a particular core fiber (block  600 ). Unless discharged, upon the incident light reaching a sensor of a distributed array of sensors measuring strain on a particular core fiber, light of a prescribed spectral width associated with the first sensor is to be reflected back to an optical receiver within a console (blocks  605 - 610 ). Herein, the sensor alters characteristics of the reflected light signal to identify the type and degree of strain on the particular core fiber as measured by the first sensor (blocks  615 - 620 ). According to one embodiment of the disclosure, the alteration in characteristics of the reflected light signal may signify a change (shift) in the wavelength of the reflected light signal from the wavelength of the incident light signal associated with the prescribed spectral width. The sensor returns the reflected light signal over the core fiber and the remaining spectrum of the incident light continues propagation through the core fiber toward a distal end of the catheter tubing (blocks  625 - 630 ). The remaining spectrum of the incident light may encounter other sensors of the distributed array of sensors, where each of these sensors would operate as set forth in blocks  605 - 630  until the last sensor of the distributed array of sensors returns the reflected light signal associated with its assigned spectral width and the remaining spectrum is discharged as illumination. 
     Referring now to  FIG. 6B , during operation, multiple reflected light signals are returned to the console from each of the plurality of core fibers residing within the corresponding plurality of micro-lumens formed within a catheter, such as the catheter of  FIG. 1B . In particular, the optical receiver receives reflected light signals from the distributed arrays of sensors located on the center core fiber and the outer core fibers and translates the reflected light signals into reflection data, namely electrical signals representative of the reflected light signals including wavelength shifts caused by strain (blocks  650 - 655 ). The reflection data classification logic is configured to identify which core fibers pertain to which reflection data and segregate reflection data provided from reflected light signals pertaining to a particular measurement region (or similar spectral width) into analysis groups (block  660 - 665 ). 
     Each analysis group of reflection data is provided to shape sensing logic for analytics (block  670 ). Herein, the shape sensing logic compares wavelength shifts at each outer core fiber with the wavelength shift at the center core fiber positioned along central axis and operating as a neutral axis of bending (block  675 ). From this analytics, on all analytic groups (e.g., reflected light signals from sensors in all or most of the core fibers), the shape sensing logic may determine the shape the core fibers have taken in three-dimensional space, from which the shape sensing logic can determine the current physical state of the catheter in three-dimension space (blocks  680 - 685 ). 
     Referring to  FIG. 7 , an exemplary embodiment of the medical instrument monitoring system of  FIG. 1B  during operation and insertion of the catheter into a patient are shown in accordance with some embodiments. Herein, the catheter  130  generally includes the integrated tubing of the catheter  130  with a proximal portion  720  that generally remains exterior to the patient  700  and a distal portion  730  that generally resides within the patient vasculature after placement is complete. The (integrated) catheter tubing of the catheter  130  may be advanced to a desired position within the patient vasculature such as a distal end (or tip)  735  of the catheter tubing of the catheter  130  is proximate the patient&#39;s heart, such as in the lower one-third (⅓) portion of the Superior Vena Cava (“SVC”) for example. In some embodiments, various instruments may be disposed at the distal end  735  of the catheter  130  to measure pressure of blood in a certain heart chamber and in the blood vessels, view an interior of blood vessels, or the like. In alternative embodiments, such as those that utilize the stylet assembly of  FIG. 1A  and the catheter  195 , such instruments may be disposed at a distal end of the stylet  120 . 
     During advancement through a patient vasculature, the catheter tubing of the catheter  130  receives broadband incident light  155  from the console  110  via optical fiber(s)  147  within the interconnect  145 , where the incident light  155  propagates along the core fibers  137  of the multi-core optical fiber  135  within the catheter tubing of the catheter  130 . According to one embodiment of the disclosure, the connector  146  of the interconnect  145  terminating the optical fiber(s)  147  may be coupled to the optical-based catheter connector  144 , which may be configured to terminate the core fibers  137  deployed within the catheter  130 . Such coupling optically connects the core fibers  137  of the catheter  130  with the optical fiber(s)  147  within the interconnect  145 . The optical connectivity is needed to propagate the incident light  155  to the core fibers  137  and return the reflected light signals  150  to the optical logic  180  within the console  110  over the interconnect  145 . As described below in detail, the physical state of the catheter  130  may be ascertained based on analytics of the wavelength shifts of the reflected light signals  150 . 
     Referring now to  FIG. 8A , an exemplary embodiment of the medical instrument monitoring system of  FIG. 1A  during operation including insertion of an implantable port catheter into a patient is shown in accordance with some embodiments. Herein, the medical instrument monitoring system is operable to insert an implantable port catheter  800  (“port catheter”) into patient  700 , where insertion may include advancing the port catheter  800  through the vasculature of the patient  700  such that the distal tip  802  of the port catheter  800  is disposed at a target location. Further, during advancement of the port catheter  800 , the stylet  120  may be disposed within the port catheter  800  in order to provide optical data to the console  110 . In some embodiments, optical data may refer to reflected light signals  150 , discussed above. The port catheter  800  may include a port connector  802  at a proximal end as shown.  FIG. 8B  illustrates the port catheter  800  coupled to an implantable port  806  (also referred to as a “totally implantable venous access device”) via the port connector  802 . 
     As with the catheter  130 , the port catheter  800  may include integrated tubing; however, the entirety of the integrated tubing remains within the patient  700 . As is shown, a distal end (or tip)  804  of the catheter tubing of the catheter  800  is proximate the patient&#39;s heart, such as in the lower one-third (⅓) portion of the Superior Vena Cava (“SVC”) for example. In some embodiments, various instruments may be disposed at the distal end  804  of the port catheter  800  to measure pressure of blood in a certain heart chamber and in the blood vessels, view an interior of blood vessels, or the like. 
     During an insertion operation, the stylet  120  may be placed within the catheter tubing of the port catheter  800  such that a distal end (or tip)  122  is located at or extends from the distal end  804 . The assembly comprising the stylet  120  and the port catheter  800  are advancement through the patient vasculature, where the stylet  120  receives broadband incident light  155  from the console  110  via optical fiber(s)  147  within the interconnect  145 , where the incident light  155  propagates along the core fibers  137  of the multi-core optical fiber  135  within the stylet  120 . According to one embodiment of the disclosure, the connector  146  of the interconnect  145  terminating the optical fiber(s)  147  may be coupled to the optical-based console connector  133 , which may be configured to terminate the core fibers  137  deployed within the stylet  120 . Such coupling optically connects the core fibers  137  of the stylet  120  with the optical fiber(s)  147  within the interconnect  145 . The optical connectivity is needed to propagate the incident light  155  to the core fibers  137  and return the reflected light signals  150  to the optical logic  180  within the console  110  over the interconnect  145 . As described above, the physical state of the stylet  120  (and thus the port catheter  800 ) may be ascertained based on analytics of the wavelength shifts of the reflected light signals  150 . 
     Referring to  FIG. 8B , an illustration of a port catheter inserted through an operation as illustrated in  FIG. 8A  is shown in accordance with some embodiments. The port catheter  800  is shown inserted into the vasculature of the patient  700  at the subclavian vein such that the distal end  804  is disposed near the SVC. Additionally,  FIG. 8B  illustrates a port  806  that has been coupled to the port catheter  800  and also implanted within the patient  700 . 
     As is known, a port such as the port  806  may include of a reservoir compartment including a septum (e.g., a self-sealing silicone layer) configured to be pierced by a needle thereby permitting access to the patient vasculature, and specific access to a location within the patient  700  located at the distal end  804  of the port catheter  800 . The access may include withdrawal of fluids, such as blood, and/or delivery of fluids, such as medication. Although shown as being inserted under the skin in the upper chest, the port catheter  800  and port  806  may be inserted elsewhere within the patient  700 . For example, the port catheter  800  may be inserted into the vasculature through the jugular vein with disposition also within the SVC. 
     Referring to  FIG. 9A , an exemplary embodiment of the medical instrument monitoring system of  FIG. 1A  with the console displaying an anticipated shape of a port catheter to be inserted into a patient is shown in accordance with some embodiments.  FIG. 9A  illustrates one example configuration of the assembly of  FIG. 8A  including the port catheter  800  and the stylet  120  for insertion of the port catheter  800 , including a detailed view of a graphical display rendered on the display  170  of the console  110 . In some embodiments, a patient graphic  900  (e.g., a template body graphic) may be displayed that includes a vasculature graphic  902  including a subclavian vein graphic  904 , an SVC graphic  906  and a heart graphic  908 . Further, the graphical display may include a graphic  910  illustrating an expected or desired placement of the port catheter  800  (“placement graphic”). 
     In one illustrative example, the console  110  may have stored thereon in the memory  165 , or have access to, one or more placement modules, where a placement module includes previously obtained positioning, shape and/or orientation data corresponding to proper insertion of a medical instrument. Additionally, a placement module includes a graphical representation of the proper insertion of the medical instrument (placement graphic). In some instances, the positioning, shape and/or orientation data may be stored as metadata to the placement graphic. A clinician may select a placement module via user input such that the placement graphic of the selected placement module is rendered on a display screen, e.g., the display  170 . For example, a placement module corresponding to the placement graphic  910  may be selected via user input. 
     Once the placement graphic  910  is selected and displayed, the insertion operation may begin including insertion of the stylet  120  within the port catheter  800 , where the stylet  120  is optically-coupled to the console  110  via the interconnect  145  such that incident light  155  propagates from the console  110  through the optical fiber core  135  of the stylet. As the port catheter  800  and stylet  120  assembly is advanced through the patient vasculature, reflected light  150  is returned to the console  110 , received by the optical logic  180  and analyzed by the shape sensing logic  194 . The analysis by the shape sensing logic  194  may result in a determination of at least the shape, location and/or positioning of the stylet  120  based on the strain detected by the gratings (sensors) fabricated within the one or more core fibers of the optical fiber core  135  deployed within the stylet  120 . 
     According to some embodiments, logic of the console further comprises artificial intelligence based (AI-based) guidance assistance logic  195 , which is configured to (i) compare the determined shape, positioning, orientation, etc., of the port catheter  800  during insertion to the selected placement, and (ii) generate an overlay graphic illustrating the determined shape, positioning, orientation, etc., as an overlay on the selected placement graphic. The term “artificial intelligence” may include machine learning and/or neural network technologies. 
     In some embodiments, the AI-based guidance assistance logic may generate the overlay graphic in a particular color based on the accuracy of the insertion operation (e.g., color adjustment based on accuracy percentage such as a first color when within a first threshold (e.g., green when insertion is at least a 95% match with the selected placement), a second color when within a second threshold (e.g., orange when insertion is between an 85-95% match with the selected placement), etc. 
     In other embodiments, the AI-based guidance assistance logic may generate the overlay graphic to include particular graphics (e.g., increased outline thickness of portions of the overlay graphic that are a substantial match with the placement graphic). Such color based or image based additions/modifications to the overlay graphic may provide better clarity as to a position of the port catheter  800  with respect to the selected placement. Besides generating the overlay graphics and additions/modifications thereto, the AI-based guidance assistance logic may be configured to generate a notification indicating the completion percentage or accuracy of the insertion operation (see  FIG. 9C ). 
     Referring now to  FIG. 9B , an illustration of the configuration of  FIG. 9A  with the console displaying the anticipated shape of a port catheter to be inserted and an overlay of the port catheter during insertion of a patient is shown in accordance with some embodiments. A graphic  912  of the determined shape, location and/or positioning of the stylet  120 , which corresponds to the same of the port catheter  800  (“real-time insertion graphic”), may be rendered on the display  170  of the console  110 . For instance, as the optical logic  180  receives reflected light  155 , which is then transformed into reflection data  192 . The shape sensing logic  194  may then analyze the reflection data  192 , determine the shape, location and/or positioning of the stylet  120  (and consequently, of the port catheter  800 ) in real-time, or substantially real-time, and ultimately render the real-time insertion graphic  912  as an overlay on patient graphic  900 . Thus, the continued rendering of the real-time insertion graphic  912  as the console  110  receives reflected light  155  provides the clinician, or medical professional, a real-time view of the propagation, positioning, shape, etc., of the port catheter  800  during the insertion operation. 
     One advantage provided by the system and configuration of  FIGS. 8A and 9A-9B  includes the ability for the clinician to not only view the propagation of the port catheter  800  within the patient using optical fiber shape sensing technology but also to visualize such propagation as an overlay to a separate graphic that illustrates the expected or desired placement. 
     The real-time insertion graphic  912  may be on heuristics or run-time analytics. For example, the shape sensing logic  194  may be configured in accordance with machine-learning techniques to access a data store (library) with pre-stored data (e.g., images, etc.) pertaining to different regions of the stylet  120  (or port catheter  800 ) in which reflected light from core fibers have previously experienced similar or identical wavelength shifts. From the pre-stored data, the current physical state of the stylet  120  (or port catheter  800 ) may be rendered. 
     Referring to  FIG. 9C , an illustration of the configuration of  FIGS. 9A-9B  with the console displaying the anticipated shape of a port catheter to be inserted and an overlay of the port catheter fully inserted of a patient is shown in accordance with some embodiments. In addition to the embodiment illustrated in  FIG. 9B , the shape sensing logic  194  may perform additional analyses on the reflection data  192  in light of the selected graphic  910 . For example,  FIG. 9C  illustrates that the shape sensing logic  194  may determine a completion percentage of the insertion operation, as illustrated by graphic  914 . In some embodiments, the graphic  914  may be rendered throughout the entire insertion process and updated in real-time to correspond to the visual of the real-time insertion graphic  912  overlaid on the placement graphic  910 . For example, the graphic  914  illustrates a progress bar illustrating the port catheter  800  is fully inserted (i.e., the progress is completely full). As the insertion operation begins, the progress bar continually updates to provide the clinician not only a visual of the advancement but also a completion percentage. Such may be accomplished through an analysis of the reflect data  192  (and determined propagation, positioning, shape, etc., of the port catheter  800 ) in view of the metadata associated with the placement graphic  910 , where the metadata may include corresponding propagation, positioning, shape, etc., represented by the placement graphic  910 . In one embodiment, machine-learning techniques may be used such that a result of a trained machine-learning model may return the completion percentage. 
     Alternatively, or in addition, machine-learning techniques may be utilized to determine the accuracy of the advancement of the port catheter  800  in view of the placement graphic  910 . As mentioned above, the placement graphic  910  may be associated with metadata that indicates the positioning of a desired placement within the patient vasculature. In some embodiments, the shape sensing logic  194  may perform an analysis that determines an accuracy percentage of the actual insertion of the port catheter  800 . Therefore, the console  110  may render the real-time insertion graphic  912  as deviating from the placement graphic  910  and also render the graphic  916  that indicates the advancement is not following the selected placement graphic  910  (see  FIG. 10 ). Further, in some embodiments, the shape sensing logic  194  may determine an internal length of the port catheter  800  and provide a rendering of such in graphic  918 . 
     Referring now to  FIG. 10 , an exemplary embodiment of the medical instrument monitoring system of  FIG. 1A  with the console displaying the anticipated shape of a port catheter to be inserted and an overlay of the port catheter off-trajectory during insertion of a patient is shown in accordance with some embodiments.  FIG. 10  provides an illustration in which the port catheter  800  is being inserted into the patient  700  and a display  170  of the console  110  including a rendering of the patient graphic  900 , the placement graphic  910  and the real-time insertion graphic  912 , each discussed above. 
     Additionally,  FIG. 10  illustrations a situation in which a blockage, e.g., plague  1000 , is present within the vasculature of the patient  700 . Thus, as the stylet  120  and the port catheter  800  are advanced and contact the plague  1000 , the distal ends  122  and  804  of the stylet  120  and port catheter  800 , respectively, deviate from the desired or expected path. As a result, the rendering on the display  170  illustrates the deviation of the distal end  1002  of the real-time insertion graphic  912  from the advancement path represented by the selected placement graphic  910 . In some embodiments, the rendering on the display  170  may include a graphic  1004  that includes a warning (or other text) indicating that advancement of the port catheter  800  has deviated from the desired trajectory. 
     Referring now to  FIGS. 11A-11B , a flowchart of an exemplary methodology of inserting a port catheter into a patient vasculature is shown in accordance with some embodiments. Each block illustrated in  FIGS. 11A-11B  represents an operation performed in the method  1100 , which is initiated when the medical instrument monitoring system of any of  FIGS. 8A-10  is deployed to insert a first medical instrument, e.g., a port catheter, into a patient vasculature, where the first medical instrument has disposed therein a second medical instrument, e.g., a stylet. For example, the second medical instrument may be the optically-enabled stylet of  FIG. 1A . According to one embodiment, the method  1100  includes receiving a selection of a desired placement of an implantable port catheter, where the selected desired placement corresponds to a stored placement graphic and rendering of the placement graphic alongside a patient graphic on a display (blocks  1102 - 1104 ). 
     Further, an optical receiver receives reflected light signals from the distributed arrays of sensors located on the core fiber(s) of s stylet disposed within the implantable port catheter during an insertion operation (block  1106 ). The reflected light signals are analyzed to determine a shape, positioning and/or orientation of the stylet, and consequently, the implantable port catheter (block  1108 ). More specifically, in embodiments in which a multi-core optical is deployed and as discussed above, the received reflected light signals are translated into reflection data, namely electrical signals representative of the reflected light signals including wavelength shifts caused by strain. The reflection data classification logic is configured to identify which core fibers pertain to which reflection data and segregate reflection data provided from reflected light signals pertaining to a particular measurement region (or similar spectral width) into analysis groups. Each analysis group of reflection data is provided to shape sensing logic for analytics, which may compare wavelength shifts at each outer core fiber with the wavelength shift at the center core fiber positioned along central axis and operating as a neutral axis of bending. 
     Based on the determined shape, positioning and/or orientation of the stylet and the implantable port catheter, a real-time insertion graphic is gendered and then rendered on the display as an overlay on the placement graphic (block  1110 ). The real-time insertion graphic illustrates at least the shape and positioning of the implantable port catheter. 
     The method  1100  continues with a determination as to whether the advancement of the implantable port catheter is within an accepted threshold of the selected placement (block  1112 ). When the advancement is outside of the acceptable threshold, an alert is generated for the clinician (block  1114 ). However, when the advancement is within an accepted threshold (e.g., advancement corresponds to the selected placement by at least 90%, although the threshold may vary), a further determination is made as to whether the insertion of the implantable port catheter is complete (block  1116 ). When the insertion operation is complete, an optional set may be performed of generating and then rendering a graphic on the display that provides particulars of the insertion operation and of the implantable port catheter, such as its internal length (block  1118 ). When the insertion operation is not complete, the method  1100  returns to block  1106  to receive further reflected light signals. 
     While some particular embodiments have been disclosed herein, and while the particular embodiments have been disclosed in some detail, it is not the intention for the particular embodiments to limit the scope of the concepts provided herein. Additional adaptations and/or modifications can appear to those of ordinary skill in the art, and, in broader aspects, these adaptations and/or modifications are encompassed as well. Accordingly, departures may be made from the particular embodiments disclosed herein without departing from the scope of the concepts provided herein.