US-12623055-B2 - Fiber optics oximetry system for detection and confirmation

US12623055B2US 12623055 B2US12623055 B2US 12623055B2US-12623055-B2

Abstract

A system, apparatus and method directed to placing a medical instrument in a vasculature of a patient body, the system including an optical fiber with one or more core fibers. The system can include a console having non-transitory computer-readable medium storing logic that, when executed, causes operations of providing an incident light signal to the optical fiber, receiving a reflected light signal of the incident light, wherein the reflected light signal is reflected from at least one of red blood cells or tissue within the patient body, processing the reflected light signal to determine an oxygen level within the patient body near a distal tip of the optical fiber. The method can include determining a location of the distal tip of the optical fiber within the patient body at least based on the oxygen level.

Inventors

William Robert McLaughlin
Steffan Sowards
Anthony K. Misener
Shayne Messerly

Assignees

BARD ACCESS SYSTEMS, INC.

Dates

Publication Date: 20260512
Application Date: 20240801

Claims (13)

1 . A non-transitory computer-readable medium having stored thereon logic that, when executed by one or more processors, causes operations including: providing an incident light signal to an optical fiber of a medical instrument, the optical fiber having one or more core fibers; receiving a reflected light signal of the incident light signal, wherein the reflected light signal is reflected from one or more of red blood cells or tissue within a patient body into which the medical instrument is inserted; processing the reflected light signal to determine an oxygen level within the patient body near a distal tip of the optical fiber, and determining a location of the distal tip of the optical fiber within the patient body based on the oxygen level and an entry site of the medical instrument.
2 . The non-transitory computer-readable medium according to claim 1 , wherein each of the one or more core fibers includes a plurality of sensors distributed along a longitudinal length thereof, and wherein 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.
3 . The non-transitory computer-readable medium according to claim 1 , wherein the optical fiber is a single-core optical fiber, and wherein providing the incident light signal includes providing the incident light signal in pulses.
4 . The non-transitory computer-readable medium according to claim 1 , wherein the optical fiber is a multi-core optical fiber including a plurality of core fibers, and wherein a first core fiber of the plurality of core fibers is configured to propagate the incident light signal and a second core fiber of the plurality of core fibers is configured to propagate the reflected light signal.
5 . The non-transitory computer-readable medium according to claim 1 , wherein determining the location of the distal tip of the optical fiber within the patient body is further based on knowledge of advancement of the medical instrument.
6 . The non-transitory computer-readable medium according to claim 1 , wherein the logic which, when executed by the one or more processors, is configured to cause further operations including generating a display indicating the location of the distal tip of the optical fiber within the patient body.
7 . The non-transitory computer-readable medium according to claim 1 , wherein the medical instrument is one of an introducer wire, a guidewire, a stylet, a needle with the optical fiber inlayed into a cannula of the needle or a catheter with the optical fiber inlayed into one or more walls of the catheter.
8 . The non-transitory computer-readable medium according to claim 1 , wherein the logic which, when executed by the one or more processors, is configured to cause further operations including detecting pneumothorax through detection of an anomalously high oxygen level.
9 . The non-transitory computer-readable medium according to claim 1 , wherein the medical instrument is configured to be placed within a vessel of the patient body, and wherein the logic which, when executed by the one or more processors, is configured to cause further operations including detecting a direction of blood flow based on an intensity of the reflected light signal.
10 . The non-transitory computer-readable medium according to claim 1 , wherein the medical instrument is configured to be placed within a vessel of the patient body, and wherein the logic which, when executed by the one or more processors, is configured to cause further operations including detecting a juncture of the vessel with a second vessel based on an increase in the oxygen level as indicated by the reflected light signal.
11 . The non-transitory computer-readable medium according to claim 1 , wherein the logic which, when executed by the one or more processors, is configured to cause further operations including detecting a change in intensity of the reflected light signal from a first intensity to a second intensity, wherein the change from the first intensity to the second intensity indicates a change in volume of blood between a first location within the patient body and a second location within the patient body.
12 . The non-transitory computer-readable medium according to claim 1 , wherein the medical instrument is a needle and is configured to be placed into a vessel of the patient body, and wherein the logic which, when executed by the one or more processors, is configured to cause further operations including detecting a first change in an intensity of the reflected light signal indicating an entry puncture by the needle with respect to the vessel and detecting a second change in the intensity of the reflected light signal indicating an exit puncture with respect to a posterior wall of the vessel.
13 . The non-transitory computer-readable medium according to claim 1 , wherein the logic which, when executed by the one or more processors, is configured to cause further operations including determining whether the optical fiber is located within an artery or a vein of the patient body based on the oxygen level.

Description

PRIORITY This application is a continuation of U.S. patent application Ser. No. 17/484,960, filed Sep. 24, 2021, now U.S. Pat. No. 12,064,569, which claims the benefit of priority to U.S. Provisional Application No. 63/083,457, filed Sep. 25, 2020, which is incorporated by reference in its entirety into this application. BACKGROUND In the past, certain intravascular guidance of medical devices, such as guidewires and catheters for example, have used fluoroscopic methods for tracking tips of the medical devices 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 device 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. Disclosed herein is a system including a medical instrument having disposed therein an optical fiber and methods performed thereby where the system is configured to provide confirmation of tip placement or tracking information using optical fiber technology. Further, the system is configured to detect oxygen levels of blood within a vasculature of a patient. Some embodiments combine the oxygen level detection functionality with one or more of a fiber optic shape sensing functionality, intravascular electrocardiogram (ECG) monitoring, impedance/conductance sensing and blood flow directional detection. SUMMARY Briefly summarized, embodiments disclosed herein are directed to systems, apparatus and methods for obtaining oximetry data (such as oxygen level) and, optionally, three-dimensional (3D) information (reflected light) corresponding to a trajectory and/or shape of a medical instrument, such as a catheter, a guidewire, or a stylet, via a fiber optic core during advancement through a vasculature of a patient, and assisting in navigation of the medical instrument during advancement. More particularly, in some embodiments, the medical instrument includes 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 light, infrared light, near infrared light, etc.) from a console during advancement through the vasculature of a patient, where the light propagates along at least a partial distance of the optical fiber core toward the distal end. For purposes of clarity, the terms incident light or broadband incident light may be utilized in the description below; however, infrared light and near infrared light may be alternatively utilized. 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 st