Imaging probe with fluid pressurizing element

Abstract

An imaging system for a patient includes an imaging probe. The imaging probe includes an elongate shaft for insertion into the patient, the elongate shaft including a proximal end, a distal portion, and a lumen extending between the proximal end and the distal portion, a rotatable optical core including a proximal end and a distal end, at least a portion of the rotatable optical core positioned within the lumen of the elongate shaft, an optical assembly positioned proximate the distal end of the rotatable optical core, the optical assembly configured to direct light to tissue and collect reflected light from the tissue, a damping fluid positioned between the elongate shaft and the rotatable optical core and configured to reduce uneven rotation of the optical assembly, and a fluid pressurizing element configured to increase pressure of the damping fluid to reduce presence of air bubbles proximate the optical assembly.

Description

[0001] Related applications

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 62 / 840,450, filed April 30, 2019, entitled “Imaging Probe with FluidPressurization Element”, the contents of which are incorporated herein by reference in their entirety.

[0003] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 017,258, filed on April 29, 2020, entitled “Imaging System”, the contents of which are incorporated herein by reference in their entirety.

[0004] This application claims the benefit of U.S. Provisional Application Serial No. 62 / 850,945, filed May 21, 2019, entitled “OCT-Guided Treatment of a Patient,” the contents of which are incorporated herein by reference in their entirety.

[0005] This application claims the benefit of U.S. Provisional Application Serial No. 62 / 906,353, filed on September 26, 2019, entitled “OCT-Guided Treatment of a Patient,” the contents of which are incorporated herein by reference in their entirety.

[0006] This application relates to U.S. Provisional Application Serial No. 62 / 148,355, filed April 16, 2015, entitled “Micro-Optic Probes for Neurology,” the contents of which are incorporated herein by reference in their entirety.

[0007] This application relates to U.S. Provisional Application Serial No. 62 / 322,182, filed April 13, 2016, entitled “Micro-Optic Probes for Neurology,” the contents of which are incorporated herein by reference in their entirety.

[0008] This application relates to the invention entitled “Micro-Optic Probes for Neurology”, filed on April 15, 2016, with publication number WO 2016 / 168605, and international PCT patent application serial number PCT / US2016 / 027764 published on October 20, 2016, the contents of which are incorporated herein by reference in their entirety.

[0009] This application relates to the invention entitled “Micro-Optic Probes for Neurology”, filed on October 12, 2017, U.S. Patent Application Serial No. 15 / 566,041, published on May 10, 2018, the contents of which are incorporated herein by reference in their entirety.

[0010] This application relates to U.S. Provisional Application Serial No. 62 / 212,173, filed on August 31, 2015, entitled “Imaging System Includes Imaging Probe and Delivery Devices,” the contents of which are incorporated herein by reference in their entirety.

[0011] This application relates to U.S. Provisional Application Serial No. 62 / 368,387, filed on July 29, 2016, entitled “Imaging System Includes Imaging Probe and Delivery Devices,” the contents of which are incorporated herein by reference in their entirety.

[0012] This application relates to the invention entitled “Imaging System Includes Imaging Probe and Delivery Devices”, filed on August 30, 2016, with publication number WO2017 / 040484, and international PCT patent application serial number PCT / US2016 / 049415 published on March 9, 2017, the contents of which are incorporated herein by reference in their entirety.

[0013] This application relates to U.S. Patent No. 10,631,718, filed February 9, 2018, and U.S. Patent Application Serial No. 15 / 751,570, published April 28, 2020, the contents of which are incorporated herein by reference in their entirety.

[0014] This application relates to U.S. Provisional Application Serial No. 62 / 591,403, filed on November 28, 2017, entitled “Imaging System,” the contents of which are incorporated herein by reference in their entirety.

[0015] This application relates to U.S. Provisional Application Serial No. 62 / 671,142, filed on May 14, 2018, entitled “Imaging System”, the contents of which are incorporated herein by reference in their entirety.

[0016] This application relates to the invention entitled “Imaging System”, filed on November 28, 2018, with publication number WO 2019 / 108598, and international PCT patent application serial number PCT / US2018 / 062766 published on June 6, 2019, the contents of which are incorporated herein by reference in their entirety.

[0017] This application relates to U.S. Provisional Application Serial No. 62 / 732,114, filed on September 17, 2018, entitled “Imaging System with Optical Pathway,” the contents of which are incorporated herein by reference in their entirety.

[0018] This application relates to the invention entitled “Imaging System with Optical Pathway”, filed on September 17, 2019, with publication number WO 2020 / 0611001, and international PCT patent application serial number PCT / US2019 / 051447 published on March 26, 2020, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0019] The present invention relates generally to imaging systems, and particularly to intravascular imaging systems including imaging probes and delivery devices. Background Technology

[0020] Imaging probes are commercially available for imaging various internal locations of patients, such as intravascular probes for imaging the heart. Current imaging probes are limited in their ability to reach specific anatomical locations due to their size and rigidity. Current imaging probes are inserted via guidewires, which can affect their placement and limit the use of one or more delivery catheters through which the imaging probe is inserted. There is a need for imaging systems that include probes with reduced diameters and high flexibility, as well as systems with one or more delivery devices compatible with these improved imaging probes. Summary of the Invention

[0021] According to one aspect of the present invention, an imaging system for a patient includes an imaging probe. The imaging probe includes: an elongated shaft including a proximal end, a distal portion, and an inner cavity extending between the proximal and distal portions; a rotatable optical core including a proximal end and a distal end, at least a portion of which is positioned within the inner cavity of the elongated shaft; an optical assembly positioned near the distal end of the rotatable optical core, the optical assembly being configured to direct light to tissue and collect reflected light from the tissue; a damping fluid positioned between the elongated shaft and the rotatable optical core and configured to reduce uneven rotation of the optical assembly; and a fluid pressurizing element configured to increase the pressure of the damping fluid to reduce the presence of air bubbles near the optical assembly; and an imaging assembly configured and arranged to be optically coupled to the imaging probe, the imaging assembly being configured to emit light into the imaging probe and receive reflected light collected by the optical assembly.

[0022] In some embodiments, the fluid pressurization element is configured to reduce bubble formation.

[0023] In some embodiments, the fluid pressurizing element is configured to reduce the growth of one or more bubbles.

[0024] In some embodiments, the fluid pressurizing element is configured to reduce the size of one or more bubbles.

[0025] In some embodiments, the system includes a beam path, and the fluid pressurizing element is configured to propel one or more bubbles to a location away from the beam path.

[0026] In some embodiments, the fluid pressurizing element is configured to generate a pressure gradient within the damping fluid.

[0027] In some embodiments, the fluid pressurization element is configured to increase the pressure of the damping fluid over a limited time period.

[0028] In some embodiments, the fluid pressurizing element is configured to intermittently increase the pressure of the damping fluid. The fluid pressurizing element may be configured to increase the pressure of the damping fluid only when imaging is likely to occur. The fluid pressurizing element may be configured to increase the pressure of the damping fluid only when the rotatable optical core is rotated. The fluid pressurizing element may be configured to increase the pressure of the damping fluid over discrete time periods not exceeding two minutes. The fluid pressurizing element may be configured to increase the pressure of the damping fluid over discrete time periods not exceeding 30 seconds. The fluid pressurizing element may be configured to increase the pressure of the damping fluid over discrete time periods not exceeding five seconds.

[0029] In some embodiments, the fluid pressurizing element is configured to generate at least the following pressures of the damping fluid: 3.6 psi; 5.0 psi; 10 psi; 15 psi; 20 psi; 30 psi; and / or 40 psi.

[0030] In some embodiments, the fluid pressurization element is configured to generate at least the following pressures for the damping fluid: 75 psi; 100 psi; 125 psi; and / or 150 psi.

[0031] In some embodiments, the fluid pressurizing element is configured to generate high-pressure and low-pressure regions within the damping fluid.

[0032] In some embodiments, the fluid pressurizing element includes a pressurizing source. The pressurizing source may include a pump. The fluid pressurizing element may further include a valve configured to allow gas to pass through while restricting the passage of the damping fluid.

[0033] In some embodiments, the fluid pressurizing element is configured to increase the pressure of the damping fluid when the rotatable optical core is rotated. The fluid pressurizing element may include at least one protrusion extending radially from the rotatable optical core. The at least one protrusion may include a plurality of protrusions, each extending radially from the rotatable optical core. The fluid pressurizing element may include a helical protrusion extending radially from the rotatable optical core. The fluid pressurizing element may include a helical coil surrounding the rotatable optical core. The helical coil may have equal spacing. The fluid pressurizing element may include an element having a propeller-like configuration. The fluid pressurizing element may include a spring-type element.

[0034] In some embodiments, the fluid pressurizing element includes a first fluid pressurizing element and a second fluid pressurizing element, and the second fluid pressurizing element is positioned near the first fluid pressurizing element. The second fluid pressurizing element may be configured to trigger the first fluid pressurizing element upon rotation.

[0035] In some embodiments, the fluid pressurizing element is viscously attached to the rotatable optical core.

[0036] In some embodiments, the fluid pressurizing element is molded on and / or molded together with the rotatable optical core.

[0037] In some embodiments, the fluid pressurization element is fused to the rotatable optical core.

[0038] In some embodiments, the fluid pressurization element is formed in the rotatable optical core. The system can be formed on the rotatable optical core via deposition and / or three-dimensional (3D) printing.

[0039] In some embodiments, the fluid pressurizing element comprises a material selected from the group consisting of: metals; plastics; stainless steel; nickel-titanium alloys; nylon; polyetheretherketone; polyimide; and combinations thereof.

[0040] In some embodiments, the rotatable optical core includes a diameter D1, and the inner cavity of the elongated shaft includes a diameter D2, and the fluid pressurizing element extends from the rotatable optical core with a radial height H1, and H1 includes at least 5% and / or no more than 95% of half the difference between D1 and D2.

[0041] In some embodiments, the rotatable optical core includes a diameter D1, and the inner cavity of the elongated shaft includes a diameter D2, and the fluid pressurizing element extends radially from the rotatable optical core with a height H1, and the gap C1 includes half the difference between D1 and D2 minus H1, and the gap C1 includes a length not exceeding 100 μm and / or not exceeding 75 μm.

[0042] In some embodiments, the fluid pressurizing element includes a cover. The cover may include elements selected from the group consisting of: a sheath; a heat-shrink tubing; a coating applied to it; a coating sprayed on it; and combinations thereof.

[0043] In some embodiments, the fluid pressurizing element is further configured to generate a prime mover, and the prime mover is configured to translate the rotatable optical core. The fluid pressurizing element may be configured to advance the rotatable optical core when rotated in a first direction, and to retract the rotatable optical core when rotated in a second direction opposite to the first direction.

[0044] In some embodiments, the damping fluid comprises a non-Newtonian fluid.

[0045] In some embodiments, the damping fluid includes a shear-thinning fluid.

[0046] In some embodiments, the damping fluid has a static viscosity of at least 500 centipoise. The damping fluid may have a shear viscosity lower than its static viscosity. The damping fluid may have a static viscosity to shear viscosity ratio of at least 1.2:1 and / or no more than 100:1.

[0047] In some embodiments, the damping fluid includes a first fluid and a second fluid. The first fluid may include a low-viscosity fluid, and the second fluid may include a high-viscosity fluid.

[0048] In some embodiments, the damping fluid comprises a low-viscosity fluid configured to reduce bubble formation. The damping fluid may include a fluid with a viscosity not exceeding 1000 centipoise.

[0049] In some embodiments, the damping fluid comprises a fluid with a high surface tension configured to reduce bubble formation. The damping fluid may include a fluid with a surface tension of at least 40 dynes / cm.

[0050] In some embodiments, the imaging probe includes a distal portion with a diameter not exceeding 0.020”. The distal portion of the imaging probe may include a diameter not exceeding 0.016”.

[0051] In some embodiments, the imaging probe further includes a sealing element in the distal portion of the elongated shaft.

[0052] According to another aspect of the present invention, an imaging probe includes: an elongated shaft including a proximal end, a distal portion, and an inner cavity extending between the proximal end and the distal portion; a rotatable optical core including a proximal end and a distal end, and at least a portion of the rotatable optical core being positioned within the inner cavity of the elongated shaft; and an optical assembly positioned near the distal end of the rotatable optical core, the optical assembly being configured to guide light to tissue and collect reflected light from the tissue; and the shaft including a proximal shaft and a distal shaft attached thereto; and the proximal shaft including a first tubular member having a first inner cavity, and the distal shaft including a second tubular member having a second inner cavity, and the shaft further including a third tubular member extending into the first inner cavity and the second inner cavity, and the shaft further including a fourth tubular member having a proximal portion surrounding the distal portion of the first tubular member and a distal portion positioned between the proximal portion of the second tubular member and the third tubular member.

[0053] In some embodiments, the first tubular member comprises a spirally cut hyaluronic acid tube.

[0054] In some embodiments, the second tubular member comprises a transparent material.

[0055] In some embodiments, the third tubular member includes an outer diameter larger than that of the first inner cavity.

[0056] In some embodiments, the fourth tubular member comprises a heat-shrinkable material.

[0057] In some embodiments, the imaging probe further includes an adhesive positioned between two or more of the first tubular member, the second tubular member, the third tubular member, and / or the fourth tubular member.

[0058] In some embodiments, the imaging probe further includes a fluid propulsion element having a diameter D1, and the third tubular member includes an inner cavity with a diameter less than D1.

[0059] In some embodiments, the second tubular member includes a protrusion extending toward the third tubular member.

[0060] In some embodiments, the second tubular member includes a maximum diameter near the third tubular member, and the fourth tubular member includes a maximum diameter near the third tubular member, and each maximum diameter is no more than 0.02”, 0.0175”, and / or 0.0155”.

[0061] In some embodiments, the fluid pressurizing element includes a first fluid pressurizing element and a second fluid pressurizing element. The first pressurizing element and the second pressurizing element can generate opposite pressure gradients when rotated.

[0062] According to another aspect of the invention, a method for producing a fluid propulsion element for an optical probe includes: providing a tube through which a mandrel is inserted; forming two or more helical channels along the length of the tube; removing a first fluid propulsion element from the mandrel; and removing a second fluid propulsion element from the mandrel.

[0063] In some embodiments, the method further includes generating a first optical probe using at least the first fluid propulsion element. The method may further include generating a second optical probe using the second fluid propulsion element.

[0064] The techniques described herein, their properties, and accompanying advantages will be best appreciated and understood in light of the following detailed description taken in conjunction with the accompanying drawings, in which representative embodiments are described by way of example.

[0065] By invoking and incorporating

[0066] All publications, patents, and patent applications mentioned in this specification are incorporated herein by reference, as if each individual publication, patent, or patent application were specifically and individually indicated to be incorporated by reference. For all purposes, the contents of all publications, patents, and patent applications mentioned in this specification are hereby incorporated in their entirety by reference. Attached Figure Description

[0067] Figure 1 A schematic diagram of an imaging system including an imaging probe with a fluid pressurization element, consistent with the concept of the present invention, is shown.

[0068] Figure 1A This demonstrates an invention consistent with the concept of the present invention. Figure 1 An enlarged view of the component within circle M1.

[0069] Figure 2 and Figure 2A The diagrams show schematics of the distal portion of the imaging probe and delivery conduit, which are consistent with the concept of this invention, as well as enlarged views of the components within circle M2.

[0070] Figure 2B and Figure 2C Schematic diagrams of the distal portion of an imaging probe, consistent with the concept of this invention, illustrating fluid flow patterns and fluid flow simulations, are shown.

[0071] Figure 3A and Figure 3B A schematic diagram of the distal portion of an imaging probe consistent with the concept of this invention is shown.

[0072] Figure 4 and Figure 4A The diagrams show schematics of the distal portion of the imaging probe and delivery conduit, which are consistent with the concept of this invention, as well as enlarged views of the components within circle M3.

[0073] Figure 5 and Figure 5A The diagrams show schematics of the distal portion of the imaging probe and delivery catheter, which are consistent with the concept of this invention, as well as enlarged views of the components within circle M4.

[0074] Figures 6A to 6C A schematic diagram of the distal portion of an optical probe consistent with the concept of this invention is shown.

[0075] Figure 7 A cross-sectional view of a segment of an imaging probe comprising an axis having a multi-part structure, consistent with the concept of this invention, is shown.

[0076] Figure 8 A cross-sectional view of a portion of an imaging probe including a bidirectional fluid propulsion element, consistent with the concept of this invention, is shown.

[0077] Figure 9A Figure 9 shows a perspective view of four steps in the process of manufacturing a fluid propulsion element, consistent with the concept of the present invention. Detailed Implementation

[0078] Reference will now be made in detail to current embodiments of the present technology, examples of which are illustrated in the accompanying drawings. Similar reference numerals may be used to refer to similar components. However, the description is not intended to limit this disclosure to the specific embodiments, but should be construed as including various modifications, equivalents, and / or substitutions to the embodiments described herein.

[0079] It will be understood that, when used herein, the words “comprising” (and any form of inclusion, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “includes” and “include”), or “containing” (and any form of containing, such as “contains” and “contain”) specifically indicate the presence of the stated feature, integer, step, operation, element, and / or component, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0080] It will be further understood that although the terms first, second, third, etc., may be used herein to describe various restrictions, elements, parts, areas, layers, and / or sections, these restrictions, elements, parts, areas, layers, and / or sections should not be limited by these terms. These terms are used only to distinguish one restriction, element, part, area, layer, or section from another. Therefore, without departing from the teachings of this application, the first restriction, element, part, area, layer, or section discussed below may be referred to as the second restriction, element, part, area, layer, or section.

[0081] It will be further understood that when an element is described as being “on,” “attached,” “connected,” or “joined” to another element, it can be directly on or above the other element, or connected to or joined to the other element, or there may be one or more intermediate elements. In contrast, when an element is described as being “directly on,” “directly attached,” “directly connected,” or “directly joined” to another element, there are no intermediate elements. Other terms used to describe the relationship between elements should be interpreted in a similar manner (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.).

[0082] It will be further understood that when the first element is referred to as being “in” or “on” and / or “within” the second element, the first element can be positioned: within the internal space of the second element, within a portion of the second element (e.g., within the wall of the second element); positioned on the outer and / or inner surface of the second element; and combinations of one or more of these.

[0083] As used herein, the term "proximity" when used to describe the proximity of a first component or location to a second component or location will be considered to include one or more locations near the second component or location, as well as locations within, above, and / or within the second component or location. For example, a component positioned proximity to an anatomical site (e.g., a target tissue location) will include components positioned near the anatomical site, as well as components positioned within, above, and / or within the anatomical site.

[0084] Spatial relative terms, such as “below,” “under,” “down,” “above,” “up,” etc., can be used to describe the relationship of one element and / or feature to another element(s) and / or another element(s) and / or another element(s)), as illustrated in the figures, for example. It will be further understood that, in addition to the orientations described in the figures, spatial relative terms are intended to encompass different orientations of the device in use and / or operation. For example, if the device in the figures is flipped, an element described as “below” and / or “under” other elements or features would then be oriented “above” other elements or features. The device can be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and thus the spatial relative terms used herein are explained.

[0085] The terms “reduce,” “reduction,” “lower,” etc., as used herein include a reduction in quantity, including a reduction to zero. Reducing the likelihood of an event occurring should include preventing its occurrence. Accordingly, the terms “prevent,” “stop,” and “avoid” should respectively include actions of “reducing,” “reduction,” and “lowering.”

[0086] The term “and / or” as used herein is considered to be a specific disclosure of each of two particular features or components, having or not having the other. For example, “A and / or B” is considered to be a specific disclosure of each of (i) A, (ii) B, and (iii) A and B as if each were described separately herein.

[0087] The term "one or more" as used herein can refer to one, two, three, four, five, six, seven, eight, nine, ten or more, up to any number.

[0088] The terms “and above” and “and these” may be used in this document following a list of items, individually or collectively. For example, a component, process, and / or other item selected from the group consisting of A, B, C, and combinations thereof should include a collection of one or more components, which includes: one, two, three, or more of item A; one, two, three, or more of item B; and / or one, two, three, or more of item C.

[0089] In this specification, unless otherwise expressly stated, “and” can mean “or”, and “or” can mean “and”. For example, if a feature is described as having A, B, or C, then the feature can have A, B, and C, or any combination of A, B, and C. Similarly, if a feature is described as having A, B, and C, then the feature can have only one or both of A, B, or C.

[0090] The expression “configured (or set) as” as used in this disclosure may be used interchangeably with expressions such as “suitable for,” “capable of,” “designed to,” “suitable for,” “manufactured as,” and “capable of,” as appropriate. The expression “configured (or set) as” does not simply mean “specifically designed to” in hardware. Alternatively, in some cases, the expression “a device configured as…” may mean that the device “can” operate with another device or component.

[0091] As used herein, the term "threshold" refers to a maximum level, minimum level, and / or range of values ​​associated with a desired or undesirable state. In some embodiments, system parameters are maintained above a minimum threshold, below a maximum threshold, within a threshold range, and / or outside a threshold range, for example, to induce a desired effect (e.g., effective treatment) and / or to prevent or otherwise reduce (hereinafter "prevent") undesirable events (e.g., device and / or clinical adverse events). In some embodiments, system parameters are maintained above a first threshold (e.g., above a first temperature threshold to induce a desired therapeutic effect on tissue) and below a second threshold (e.g., below a second temperature threshold to prevent undesirable tissue damage). In some embodiments, thresholds are determined to include safety margins, such as to account for patient variability, system variability, tolerances, etc. As used herein, "exceeding a threshold" refers to a parameter being above a maximum threshold, below a minimum threshold, within a threshold range, and / or outside a threshold range.

[0092] As described herein, “chamber pressure” refers to the pressure of the environment surrounding the systems and devices of this invention. Positive pressure includes pressures above chamber pressure, or simply pressures greater than another pressure, such as a positive differential pressure on a fluid passage component (e.g., a valve). Negative pressure includes pressures below chamber pressure, or pressures less than another pressure, such as a negative differential pressure on a fluid passage component (e.g., a valve). Negative pressure can include vacuum, but does not imply a pressure below vacuum. As used herein, the term “vacuum” can be used to refer to a complete or partial vacuum, or any negative pressure as described above.

[0093] The term "diameter" as used herein to describe non-circular geometries is considered to be the diameter of an imaginary circle that approximates the geometry being described. For example, when describing a cross-section, such as the cross-section of a component, the term "diameter" should be considered to represent the diameter of an imaginary circle having the same cross-sectional area as the cross-section of the component being described.

[0094] The terms "major axis" and "minor axis" for a component, when used in this document, refer to the length and diameter of the smallest imaginary cylinder that can completely enclose the component.

[0095] As used herein, the term "functional element" will be considered to include one or more elements configured and arranged to perform a function. A functional element may include sensors and / or transducers. In some embodiments, a functional element is configured to deliver energy and / or otherwise treat tissue (e.g., a functional element configured as a therapeutic element). Alternatively or additionally, a functional element (e.g., a functional element including sensors) may be configured to record one or more parameters, such as patient physiological parameters; patient anatomical parameters (e.g., tissue geometry parameters); patient environmental parameters; and / or system parameters. In some embodiments, sensors or other functional elements are configured to perform diagnostic functions (e.g., to collect data for performing a diagnosis). In some embodiments, a functional element is configured to perform therapeutic functions (e.g., to deliver therapeutic energy and / or therapeutic agents). In some embodiments, a functional element includes one or more elements configured and arranged to perform a function selected from the group consisting of: delivering energy; extracting energy (e.g., for cooling components); delivering drugs or other agents; manipulating system components or patient tissue; recording or otherwise sensing parameters, such as patient physiological parameters or system parameters; and combinations of one or more of these. A functional element may include fluids and / or fluid delivery systems. Functional elements may include reservoirs, such as inflatable balloons or other fluid sustaining reservoirs. A "functional component" may include components configured and arranged to perform a function, such as diagnostic and / or therapeutic functions. A functional component may include inflatable components. A functional component may include one or more functional elements.

[0096] The term "transducer," as used herein, is considered to include any component or combination of components that receives energy or any input and produces an output. For example, a transducer may include electrodes that receive electrical energy and (e.g., based on electrode size) distribute that electrical energy to tissue. In some configurations, a transducer converts an electrical signal into any output, such as light (e.g., a transducer including a light-emitting diode or light bulb), sound (e.g., a transducer including a piezoelectric crystal configured to deliver ultrasonic energy), pressure, heat, cryogenic energy, chemical energy; mechanical energy (e.g., a transducer including a motor or solenoid), magnetic energy, and / or various electrical signals (e.g., Bluetooth or other wireless communication elements). Alternatively or additionally, a transducer may convert a physical quantity (e.g., a change in a physical quantity) into an electrical signal. A transducer may include any component that delivers energy and / or agents to a tissue, such as a transducer configured to deliver one or more of the following: electrical energy to the tissue (e.g., a transducer including one or more electrodes); optical energy to the tissue (e.g., a transducer including a laser, a light-emitting diode, and / or optical components such as lenses or prisms); mechanical energy to the tissue (e.g., a transducer including tissue manipulation elements); acoustic energy to the tissue (e.g., a transducer including a piezoelectric crystal); chemical energy; electromagnetic energy; magnetic energy; and combinations of one or more of these.

[0097] As used herein, the term "fluid" can refer to a liquid, gas, gel, or any flowable material, such as a material that can be propelled through cavities and / or openings.

[0098] It should be understood that certain features of the inventive concept described in the context of a single embodiment for clarity may also be provided in combination in a single embodiment. Conversely, various features of the inventive concept described in the context of a single embodiment for brevity may also be provided individually or in any suitable sub-combination. For example, it will be understood that all features set forth in any claim (whether independent or dependent) may be combined in any given manner.

[0099] It should be understood that at least some of the figures and descriptions in this invention have been simplified to focus on elements relevant to a clear understanding of the inventive concept, while other elements that would be understood by one of ordinary skill in the art to also be part of the inventive concept have been omitted for clarity. However, because these elements are well known in the art, and because they do not necessarily contribute to a better understanding of the invention, a description of these elements is not provided herein.

[0100] The terminology defined in this disclosure is used only to describe specific embodiments of the disclosure and is not intended to limit the scope of the disclosure. Terms provided in the singular are intended to include the plural as well, unless the context clearly indicates otherwise. Unless otherwise defined herein, all terms used herein (including technical or scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. Unless expressly defined herein, terms defined in commonly used dictionaries should be interpreted as having the same or similar meaning as in the context of the related art and should not be interpreted as having an ideal or exaggerated meaning. In some cases, the terms defined in this disclosure should not be construed as excluding embodiments of the disclosure.

[0101] This document provides an imaging system for a patient, comprising an imaging probe and an imaging assembly optically coupled to the imaging probe. The probe includes an elongated shaft, a rotatable optical core, and an optical assembly. The rotatable optical core is positioned within a cavity of the elongated shaft. The optical assembly is positioned near the distal end of the optical core and is configured to direct light to tissue and collect reflected light from the tissue. When optically coupled to the imaging probe, the imaging assembly is configured to emit light into the imaging probe and receive the reflected light collected by the optical assembly, for example, to provide images of blood vessels and devices positioned within them. The probe may include a damping fluid positioned between the elongated shaft and the rotatable optical core, and this damping fluid may be configured to reduce uneven rotation of the optical assembly, thereby reducing undesirable distortion of the images generated by the system. The probe may further include a fluid pressurization element configured to increase the pressure of the damping fluid to reduce the presence of air bubbles near the optical assembly (e.g., air bubbles that limit or reduce the image quality generated by the system).

[0102] When planning and applying treatment, vascular imaging is a primary diagnostic tool, such as thrombolytic drugs or stent thrombectomies for clot removal (e.g., ischemic stroke) or coils, drains, and other devices for aneurysm repair (e.g., hemorrhagic stroke). External non-invasive imaging, such as X-ray angiography or magnetic resonance imaging (MRI), is the primary imaging technique; however, such techniques only provide information on vessel size and shape and have moderate resolution (~0.2 mm or 200 μm). This level of resolution cannot image important, smaller features present in the vascular system. The inability to adequately image these vessels limits preoperative planning and acute assessment of treatment outcomes. The effectiveness of these imaging techniques is further limited by the shadowing and localized image elimination produced by the treatment itself in the case of coils. Therefore, it is desirable to also perform the intravascular imaging of the present invention to examine the detailed morphology of the internal vessel walls and / or better plan and assess the outcomes of catheter-based interventions. Currently, intravascular imaging techniques, such as intravascular ultrasound (IVUS) and intravascular optical coherence tomography (OCT), have been developed and approved for use in the coronary arteries. IVUS is also used for larger peripheral vascular systems. However, apart from the larger carotid arteries, intravascular imaging has not yet been extended to neurovascular systems. This limitation is mainly due to two reasons: neurovascular size can become very small, approximately 1 mm in diameter or less, and the tortuosity of the vessels becomes quite high. Therefore, smaller and more flexible imaging probes are needed, such as probes capable of safely and effectively navigating the tortuous carotid sinus to reach the middle cranial artery and its more distant branches and segments, and imaging the middle cranial artery and its more distant branches and segments.

[0103] Due to the fundamental limitations of ultrasound resolution, especially the unavoidable beam divergence when using small transducers, optical techniques are preferred. In particular, with the advent of new light sources, such as broadband superluminescent light-emitting diodes (SLEDs), supercontinuum lasers, compact swept-frequency sources, miniature optical systems, and the use of techniques like optical coherence tomography (OCT) for interferometry of returned light—all compatible with single-mode fiber—the use of optical techniques has become highly advantageous from both clinical and commercial perspectives. Furthermore, the use of single-mode fiber allows for the consideration of the smallest possible imaging probe.

[0104] Generally, to generate a three-dimensional (3D) view of the vessel wall, light delivered by the distal imaging optics of an inserted probe can sweep across the surface of the lumen through simultaneous axial translation (“pull-back”) and rotation of the optics and attached optical fibers. To facilitate accurate, distortion-free imaging, the distal rotation rate should be uniform in speed. Due to size and cost, the drive motor causing the rotation is located proximal to the patient, externally, and separate from the imaging probe (e.g., configured for reusable arrangements to be used with multiple imaging probes). The natural tendency of the probe's optical fiber is to “whip” at the distal end, resulting in an effect known as non-uniform rotational distortion (NURD). To overcome this undesirable effect, tightly wound spring-like coils called torque wires (with the optical fiber at the center of the coil) have been used to reduce non-uniform rotation of the distal optics. These torque wires can increase the volume of the catheter (e.g., increased diameter), have tortuosity limits (beyond which NURD reappears), and can be costly. Furthermore, the torque line is sensitive to the total cumulative tortuosity integrated along the length of the conduit, and since the torque line must be attached to the proximal drive source, this total integrated tortuosity can become significant (e.g., causing NURD to reappear). Because only the optics at the distal end require uniform rotation, the rotation of components near the distal optics does not need to be similarly controlled; in other words, as long as the rotational speed of the distal optics remains relatively constant, the fiber can be twisted and untwisted in the proximal region with variations in tortuosity without generating NURD. Therefore, the configuration of controlling uniform rotation of the distal optics without the torque line avoids many limitations and offers many advantages.

[0105] To overcome the limitations of the torque line, damping fluids have been used to control rotational speed variations. For example, U.S. Patent 6,891,984 ('984 patent) describes the use of a viscous fluid to induce fiber "winding" and rotational energy storage. The unwinding rate is also determined by the fluid's viscosity, which can provide an effective feedback mechanism for rotational control. Any fluid on the lens needs to meet desired optical properties, particularly optical indices within acceptable ranges to minimize cylindrical distortion and low absorption at the operating wavelength. The fluid chosen can include biocompatible fluids, as they are temporarily located within the body. If not biocompatible, additional protective layers can be added to prevent undesirable single-failure conditions (e.g., leakage).

[0106] The systems conceived in this invention may include non-Newtonian fluids and / or shear-thinning fluids, for example, to accommodate high-speed rotation, as described in co-pending U.S. Patent Application Serial No. 15 / 566,041, filed October 12, 2017, entitled “Micro-Optic Probes for Neurology”.

[0107] Fluid-based rotational control solutions (e.g., fluid damping solutions) are prone to bubble formation within the fluid. While bubbles typically have a minor impact on mechanical properties, it is readily understood that bubbles located along the path of light delivery and / or reception (“beam path”) will have a significant and undesirable effect on image quality. Bubble formation is inherent to rotating elements in fluid fields, for example via a phenomenon known as cavitation. Bubbles can also be generated in fluids at fluid-solid interfaces through nucleation, but cavitation typically dominates under high-speed rotation. Due to the need to guide the beam relatively orthogonally to the probe axis, a certain asymmetry will exist in the distal optics (e.g., a lens assembly with a beveled distal end configured to guide light at 90° to the axis of the distal end of the attached fiber), and thus a tendency to generate low-pressure regions often occurs during high-speed rotation.

[0108] Cavitation refers to the presence of small vapor-filled regions (“bubbles”) that result when a liquid undergoes rapid pressure changes, causing cavitation to form in regions of relatively low pressure. The systems conceived in this invention have several general characteristics that can be optimized to minimize cavitation and its associated bubble formation. For example, the geometry of the imaging probe (e.g., the space in which the damping fluid is located) can be constructed and arranged to minimize bubble formation. The viscosity of the included damping fluid can be selected to limit bubble formation. The damping fluid may include fluids with low vapor pressure and / or low levels of dissolved gases (or multiple gases). The damping fluid may include fluids with high surface tension (e.g., those that tend to cause bubble collapse). The damping fluid may include fluids with low surface tension (e.g., if bubble formation is caused by nucleation), such as wetting agents. Low-viscosity fluids will tend to reduce bubble formation, but these low-viscosity fluids alone cannot effectively control NURD. Combinations of two or more fluids (e.g., in a stacked arrangement) may be used, for example, when one or more sealing elements are included to maintain fluid separation. Low-viscosity fluids can be positioned above the distal optics (e.g., only above the distal optics), and high-viscosity fluids are placed near the low-viscosity fluids and extend over a relatively long segment of the imaging probe. In some embodiments, one or more damping fluids are used, wherein the one or more damping fluids include: viscosity selected to reduce bubble formation; low vapor pressure; low levels of dissolved gases; low surface tension; and / or high surface tension.

[0109] In some embodiments, the pressure of the included damping fluid (or other fluid) can be increased, for example, to cause an effect selected from the group consisting of: reducing bubble formation; reducing the growth of one or more bubbles (e.g., one or more existing bubbles); reducing the size of one or more bubbles (e.g., one or more existing bubbles); advancing one or more bubbles to a location away from the beam path; and combinations thereof. The increased pressurization of the damping fluid can be performed for a limited time, as prolonged pressurization may cause the fluid to absorb additional gas, thereby causing the establishment of new vapor pressure. The pressurizing elements of the present invention can have a small size (e.g., compact) so that they can be enclosed within the probe. These pressurizing elements can only be activated (e.g., to generate increased damping fluid pressure) when actual imaging is taking place (e.g., when the fiber optics and distal optics are rotating at high speed), for example, to avoid establishing an undesirable equilibrium state caused by prolonged pressurization.

[0110] All of the above bubble reduction configurations can be applied individually and / or in combination to prevent, limit, and / or reduce bubble formation near the distal optics of the probe.

[0111] The system conceived in this invention may include a probe with a fluid pressurizing element configured to "minimize bubble effects" (e.g., reduce the presence of bubbles at one or more locations), which should include: preventing, limiting, and / or reducing the formation of one or more bubbles; limiting and / or reducing the expansion of one or more bubbles; reducing the size of one or more bubbles; and / or moving one or more bubbles away from the beam path (e.g., moving one or more bubbles away from an optical component that transmits light to and / or from tissue).

[0112] Now for reference Figure 1 A schematic diagram of an imaging system consistent with the concept of the present invention is shown, which includes an imaging probe with a fluid pressurization element. See also... Figure 1AAn enlarged view of the components within circle M1, consistent with the inventive concept, is shown. Imaging system 10 is configured and arranged to collect image data and generate one or more images based on the recorded data, such as when imaging system 10 includes an optical coherence tomography (OCT) imaging system configured and arranged to collect image data of imaging locations (e.g., vascular segments, such as during a retraction procedure). Imaging system 10 includes a catheter-based probe, imaging probe 100, and a rotation assembly 500 and a retraction assembly 800, each of which is operatively attached to imaging probe 100. Imaging system 10 may further include a console 50 configured to be operatively connected to imaging probe 100, for example, via rotation assembly 500 and / or retraction assembly 800. Imaging probe 100 can be guided into a patient's conduit (e.g., a patient's blood vessel or other conduit) via one or more delivery catheters (e.g., delivery catheter 80 shown). Additionally or alternatively, the imaging probe 100 may be guided by a guide device (such as an endoscope, arthroscopy, balloon dilator, etc.). In some embodiments, the imaging probe 100 is configured to be guided into a conduit selected from the group consisting of: arteries; veins; arteries within or near the heart; veins within or near the heart; arteries within or near the brain; veins within or near the brain; peripheral arteries; peripheral veins; conduits entering through natural body orifices, such as the esophagus; conduits entering through surgically created orifices, such as the abdomen; and combinations of one or more of these. The imaging system 10 may further include additional imaging devices, such as the second imaging device 15 shown. The imaging system 10 may further include a treatment device 16 configured to treat a patient. The imaging system 10 may further include a fluid injector, such as injector 20, which may be configured to inject one or more fluids, such as flushing fluids, imaging contrast agents (e.g., radiopaque contrast agents, hereinafter referred to as "contrast agents"), and / or other fluids, such as injectable 21 shown. The imaging system 10 may further include an implant (such as implant 31) that can be implanted into the patient via a delivery device (such as implant delivery device 30 and / or delivery catheter 80).

[0113] In some embodiments, the imaging probe 100 and / or another component of the imaging system 10 may have a similar construction and arrangement to those described in co-pending U.S. Patent Application Serial No. 15 / 566,041, filed October 12, 2017, entitled “Micro-Optic Probes for Neurology,” and / or co-pending U.S. Provisional Patent Application Serial No. 62 / 732,114, filed September 17, 2018, entitled “Imaging System with Optical Pathway.” The imaging probe 100 may be constructed and arranged to collect image data from a patient site, such as an intravascular cardiac site, an intracranial site, or other sites accessible via the patient’s vascular system. In some embodiments, the imaging system 10 may have a similar construction and arrangement to that of a similar system and method of use described in co-pending U.S. Patent Application Serial No. 15 / 751,570, filed February 9, 2018, entitled “Imaging System includes Imaging Probe and Delivery Devices”.

[0114] The delivery conduit 80 includes: an elongated shaft 81 with an inner lumen 84 passing through it; and a connector 82 positioned at its proximal end. The connector 82 may include a Touhy connector or other valved connectors, such as valved connectors configured to prevent fluid from flowing out of the associated delivery conduit 80 (having and / or not having a separate shaft positioned within the connector 82). The connector 82 may include ports 83, such as ports configured and arranged to allow fluid to be directed into and / or removed from the delivery conduit 80. In some embodiments, flushing fluid, as described below, is directed via one or more ports 83, for example, to remove blood or other unwanted substances from a location near the optical component (e.g., from a location proximal to the optical component (e.g., distal to the optical component 115 described below)). The ports 83 may be positioned on one side of the connector 82 and may include Luer fittings and caps and / or valves. Shaft 81, connector 82, and port 83 may all comprise standard materials and have a construction similar to commercially available guides, guiding catheters, diagnostic catheters, intermediate catheters, and microcatheters for interventional procedures. Delivery catheter 80 may include a catheter configured to deliver imaging probe 100 (via lumen 84) to an intracerebral, intracardiac, and / or other location within the patient.

[0115] The imaging system 10 may include two or more delivery catheters 80, such as three or more delivery catheters 80. The multiple delivery catheters 80 may include at least a vascular guide, and other delivery catheters 80 that can be inserted into the patient's body through the vascular guide after it has been positioned across the patient's skin. Two or more delivery catheters 80 may collectively include an inner diameter (ID) and an outer diameter (OD) set such that a first delivery catheter 80 slidably receives a second delivery catheter 80 (e.g., the second delivery catheter OD is less than or equal to the first delivery catheter ID), and a second delivery catheter 80 slidably receives a third delivery catheter 80 (e.g., the third delivery catheter OD is less than or equal to the second delivery catheter ID), and so on. In these configurations, the first delivery catheter 80 may advance to a first anatomical position, the second delivery catheter 80 may advance through the first delivery catheter to a second anatomical position distal to or otherwise remote from (hereinafter referred to as distal) the first anatomical position, and so on, using delivery catheters 80 of smaller diameters as appropriate. The probe 100 can be advanced through and / or along one or more of the delivery conduits 80 (e.g., through the lumen of the smallest delivery conduit 80). In some embodiments, the delivery conduit 80 may have a similar construction and arrangement to similar components described in co-pending U.S. Patent Application Serial No. 15 / 751,570, filed February 9, 2018, entitled “Imaging System includes Imaging Probe and Delivery Devices”.

[0116] Imaging probe 100 includes an elongated body comprising one or more elongated shafts and / or other tubes, referred to herein as an elongated shaft 120. Shaft 120 includes a proximal end 1201, a distal end 1209, and an inner cavity 1205 extending between the proximal and distal ends. In some embodiments, the inner cavity 1205 includes a plurality of coaxial cavities within one or more elongated shafts 120, such as one or more cavities adjacent to each other to define a single inner cavity 1205. In some embodiments, at least a portion of shaft 120 includes a torque shaft. In some embodiments, a portion of shaft 120 includes a braided construction. Shaft 120 is operatively positioned around a rotatable optical fiber: an optical core 110 (e.g., an optical core 110 is positioned within the inner cavity 1205), the optical core including a proximal end 1101 and a distal end 1109 (the proximal end 1101 is not shown, but is close to the proximal end 1201 of shaft 120). Optical core 110 may include dispersion-shifted fiber, such as a recessed cladding dispersion-shifted fiber. Axis 120 further includes a distal portion 1208 comprising a transparent window: window 130 (e.g., a window relatively transparent to light of one or more frequencies transmitted through optical core 110). Window 130 may comprise the entire circumferential portion of the distal portion 1208 of axis 120. Optical assembly: Optical assembly 115 is operatively attached to the distal end 1109 of optical core 110 (e.g., such that optical assembly 115 rotates in unison with optical core 110). Optical assembly 115 is positioned within window 130 of axis 120. Connector assembly: Connector assembly 150 is positioned on the proximal end of axis 120. Connector assembly 150 operatively attaches imaging probe 100 to rotation assembly 500, such that rotation assembly 500 is operatively attached to optical core 110. Rotation assembly 500 may be configured to rotate optical core 110 within axis 120, as described herein. Connector assembly 150 may have a similar construction and arrangement to similar components described in co-pending international PCT patent application serial number PCT / US2018 / 062766, filed November 28, 2018, entitled “Imaging System,” and co-pending U.S. provisional patent application serial number 62 / 732,114, filed September 17, 2018, entitled “Imaging System with Optical Pathway.” A second connector, pull-back connector 858, is positioned on shaft 120. Connector 858 may be removably attached and / or adjustablely positioned along the length of shaft 120. Connector 858 may be positioned by the operator along shaft 120, for example, near the proximal end of delivery catheter 80 (e.g., proximal to connector 82 of delivery catheter 80), after the imaging probe 100 has been inserted into the patient via delivery catheter 80.Shaft 120 may include a portion between the placement of connector assembly 150 and connector 858, the portion being adapted to slack in shaft 120, a proximal portion of shaft 120 (e.g., a proximal portion of imaging probe 100), and service ring 185.

[0117] Imaging probe 100 may include one or more visual markers along its length (e.g., along axis 120), as shown by markers 131a-b (marker 131 herein). Marker 131 may include markers selected from the group consisting of: radiopaque markers; ultrasound reflective markers; magnetic markers; ferrous metallic materials; visible markers; and combinations of one or more of these. In some embodiments, marker 131 includes markers positioned at locations (e.g., within and / or at least adjacent to the distal portion 1208) to assist the operator of imaging system 10 in performing a pull-back procedure (e.g., a pull-back procedure using fluorescence examination and / or external ultrasound imaging), such as positioning the distal end 1209 of axis 120 at a location proximal to the implant after pull-back (e.g., allowing imaging probe 100 to be safely advanced through the implant after pull-back).

[0118] In some embodiments, the imaging probe 100 includes a viscous damping fluid or other damping material, gel 180, positioned within an inner cavity 1205 of the shaft 120 and configured to reduce uneven rotation of the optical component 115. The gel 180 may surround at least a distal portion of the optical core 110. The gel 180 may further surround the optical component 115. The gel 180 may include a non-Newtonian fluid, such as a shear-thinning fluid. In some embodiments, the gel 180 has a static viscosity of at least 500 centipoise and a shear viscosity less than that static viscosity. In these embodiments, the ratio of the static viscosity to the shear viscosity of the gel 180 may be between 1.2:1 and 100:1. Gel 180 may include gels as described in co-pending U.S. Patent Application Serial No. 15 / 566,041, filed October 12, 2017, entitled “Micro-OpticProbes for Neurology,” and co-pending International PCT Patent Application Serial No. PCT / US2018 / 062766, filed November 28, 2018, entitled “Imaging System.”

[0119] Imaging probe 100 may include a distal end portion, distal end 119. In some embodiments, distal end 119 includes a spring end, such as a spring end configured to improve the "navigability" (e.g., to improve the "trackability" and / or "maneuverability" of imaging probe 100, for example, within a tortuous pathway (e.g., within a blood vessel in the brain or heart with a tortuous pathway). In some embodiments, end 119 includes a length between 5 mm and 100 mm (e.g., a spring with a length between 5 mm and 100 mm). Alternatively or additionally, end 119 may include a cap, plug, or other element configured to seal the distal opening of window 130. In some embodiments, end 119 includes a radiopaque marker configured to improve the visibility of imaging probe 100 under X-ray or fluorescence microscopy. In some embodiments, end 119 includes a relatively short luminal guidewire passage to allow for "quick-change" translation of imaging probe 100.

[0120] In some embodiments, at least the distal portion of the imaging probe 100 (e.g., the distal portion of the shaft 120 surrounding the optical assembly 115) includes an outer diameter of no more than 0.020” or no more than 0.016”.

[0121] In some embodiments, the imaging probe 100 is configured and arranged for use in intravascular neural procedures (e.g., procedures in which blood, the vascular system, and other tissues near the brain are visualized, and / or devices temporarily or permanently located near the brain are visualized). The imaging probe 100 configured for use in neural procedures may include a total length of at least 150 cm, such as approximately 300 cm.

[0122] Alternatively or additionally, the imaging probe 100 may be configured and arranged for use in intravascular cardiac procedures (e.g., procedures in which blood, the vascular system, and other tissues near the heart are visualized, and / or devices temporarily or permanently positioned near the heart are visualized). An imaging probe 100 configured for use in cardiovascular procedures may include a total length of at least 120 cm, such as approximately 280 cm. In some embodiments, the imaging probe 100 includes a length of at least 260 cm and / or up to 320 cm.

[0123] Rotation component 500 is operatively attached to connector 150 of imaging probe 100. Rotation component 500 may include one or more rotary joints, optical connectors, rotational power sources, and / or linkages configured to operatively attach to and rotate optical core 110. Connector 150 may be constructed and arranged to be removably attached to rotation component 500 and allow rotational connection between proximal end 1101 and rotating fiber optic connector (such as a fiber optic rotary connector or FORJ). Rotation component 500 may have a similar construction and arrangement to similar components described in co-pending international PCT patent application serial number PCT / US2018 / 062766, filed November 28, 2018, entitled “Imaging System,” and co-pending U.S. provisional patent application serial number 62 / 732,114, filed September 17, 2018, entitled “Imaging System with Optical Pathway.” The rotating assembly 500 can be configured to rotate the optical core 110 at a speed of at least 100 revolutions per second (e.g., at least 200 or 250 revolutions per second, or between 20 and 1000 revolutions per second). The rotating assembly 500 may include a rotational energy source selected from the group consisting of: a motor; a servo system; a stepper motor (e.g., a stepper motor including a gearbox); a linear actuator; a hollow core motor; and combinations thereof. In some embodiments, the rotating assembly 500 is configured to rotate the optical assembly 115 and the optical core 110 in unison.

[0124] Retraction assembly 800 is operatively attached to imaging probe 100, for example, to retract imaging probe 100 relative to a patient entry site. Retraction element 850 may be operatively attached to retraction assembly 800 and imaging probe 100, for example, to transmit retraction force from retraction assembly 800 to imaging probe 100. Retraction element 850 may include conduit 855 surrounding linkage 856, which is slidably received within conduit. Retraction element 850 may include connector 852 operatively attached to retraction assembly 800 such that retraction assembly 800 can retract linkage 856 relative to conduit 855. In some embodiments, conduit 855 includes connector 857 operatively attached to a reference point near the patient entry site, such as connector 82 attached to delivery catheter 80, to establish a reference for retraction of imaging probe 100 relative to the patient. Connector 857 may be attached to a reference point, such as a patient guide device, operating table, and / or another fixed or semi-fixed reference point. Linkage 856 is releasably attached to connector 858 of imaging probe 100. Retraction assembly 800 retracts at least a portion of imaging probe 100 (e.g., a portion of imaging probe 100 distal to the attached connector 858) relative to an established reference by retracting linkage 856 relative to conduit 855 (e.g., retracting a portion of linkage 856 away from conduit 855, as shown). In some embodiments, retraction assembly 800 is configured to retract at least a portion of imaging probe 100 (e.g., at least optical component 115 and a portion of shaft 120) at a rate between 5 mm / sec and 200 mm / sec, or between 5 mm / sec and 100 mm / sec (e.g., a rate of approximately 60 mm / sec). Additionally or alternatively, the pull-back procedure may be performed over a time period between 0.5 seconds and 25 seconds (e.g., approximately 20 seconds (e.g., at a speed of 5 mm / sec over a distance of 100 mm)). The service ring 185 of the imaging probe 100 can be positioned between the connector 857 and the rotating assembly 500, such that the imaging probe 100 can be retracted relative to the patient while the rotating assembly 500 remains stationary (e.g., attached to the operating table and / or to a portion of the console 50).

[0125] The retraction assembly 800 further includes a power element configured as a retraction linkage 856. In some embodiments, the power element includes a linear actuator, a worm gear drive operably attached to a motor, a pulley system, and / or other linear force transmission mechanism. The linkage 856 may be operably attached to the power element via one or more linkages and / or connectors. The retraction assembly 800 may have a similar construction and arrangement to similar components described in co-pending international PCT patent application serial number PCT / US2018 / 062766, filed November 28, 2018, entitled “Imaging System.”

[0126] In some embodiments, the imaging system 10 includes a patient interface unit 200. The patient interface unit 200 may include a single housing that houses both the rotating assembly 500 and the retractable assembly 800. Alternatively or additionally, the patient interface unit 200 may include two or more housings, such as a separate housing for each of the rotating assembly 500 and the retractable assembly 800. In some embodiments, the connector 150, service ring 185, retractable element 850, and connector 852 are housed in a single housing and configured to be operatively attached to both the rotating assembly 500 and the retractable assembly 800 (e.g., when the rotating assembly 500 and the retractable assembly 800 are housed within a single housing).

[0127] The console 50 includes an imaging component 300, a user interface 55, a processor 52, and one or more algorithms 51. The imaging component 300 may be configured to (e.g., via optical core 110) provide light to and collect light from optical component 115. The imaging component 300 may include a light source 310. The light source 310 may include one or more light sources, such as one or more light sources configured to provide light of one or more wavelengths to optical component 115 via optical core 110. The light source 310 is configured to provide light to optical component 115 (via optical core 110) such that image data can be collected, including cross-sectional, longitudinal, and / or volumetric information relating to the imaged patient site or implanted device. The light source 310 may be configured to provide light such that the collected image data includes tissue characteristics within the imaged patient site, such as providing information, quantified, defined, or otherwise, relating to a patient disease or disorder present in the imaged patient site. Light source 310 can be configured to deliver broadband light and have a center wavelength in the range of 350 nm to 2500 nm, 800 nm to 1700 nm, 1280 nm to 1310 nm, or approximately 1300 nm (e.g., light delivered in a scanning range of 1250 nm to 1350 nm). The bandwidth of light source 310 can be selected to achieve a desired resolution, which can vary depending on the intended use of imaging system 10. In some embodiments, the bandwidth is approximately 5% to 15% of the center wavelength, thus allowing a resolution between 20 μm and 5 μm. Light source 310 can be configured to deliver light at a power level that meets ANSI Class 1 (“eye safety”) limits, although higher power levels can be employed. In some embodiments, light source 310 delivers light at a power level of approximately 20 mW in the 1.3 μm band. As the center wavelength of the transmitted light increases, tissue light scattering decreases, but water absorption increases. Light source 310 can deliver light with wavelengths close to 1300 nm to balance these two effects. Light source 310 can be configured to deliver shorter wavelength light (e.g., approximately 800 nm) to pass through the patient site to be imaged, which includes a large amount of fluid. Alternatively or additionally, light source 310 can be configured to deliver longer wavelength light (e.g., approximately 1700 nm) to reduce high levels of scattering within the patient site to be imaged. In some embodiments, light source 310 includes a tunable light source (e.g., light source 310 emits a single wavelength that varies repeatedly over time) and / or a broadband light source. Light source 310 can include a single spatial mode light source or a multi-mode light source (e.g., a multi-mode light source with spatial filtering).Imaging assembly 300 may have a similar construction and arrangement to similar components described in co-pending U.S. Provisional Patent Application Serial No. 62 / 732,114, filed September 17, 2018, entitled “Imaging System with Optical Pathway”.

[0128] The console 50 may include one or more algorithms (such as algorithm 51 shown) that can be configured to adjust (e.g., automatically and / or semi-automatically) one or more operating parameters of the imaging system 10, such as those of the console 50, the imaging probe 100, and / or the delivery catheter 80. The console 50 may further include a processing component: a processor 52 configured to execute algorithm 51 and / or perform any type of data processing, as described below. Figure 4The described digital signal processing. Additionally or alternatively, algorithm 51 may be configured to adjust operating parameters of individual devices (such as syringe 20 or implant delivery device 30 described below). In some embodiments, algorithm 51 is configured to adjust operating parameters based on one or more sensor signals (such as sensor signals provided by sensor-based functional elements of the inventive concept described herein). Algorithm 51 can be configured to adjust operating parameters selected from a group consisting of: rotational parameters, such as the rotational speed of optical core 110 and / or optical component 115; retraction parameters of axis 120 and / or optical component 115, such as retraction speed, distance, start position, end position, and / or retraction initiation timing (e.g., the time to initiate retraction); positional parameters, such as the position of optical component 115; line spacing parameters, such as the number of lines per frame; image display parameters, such as the scaling ratio of display size to blood vessel diameter; configuration parameters of imaging probe 100; parameters of injectable material 21, such as the ratio of saline to contrast agent configured to determine a suitable refractive index; parameters of light source 310, such as the delivered power and / or the frequency of delivered light; and combinations of one or more of these. In some embodiments, algorithm 51 is configured to adjust retraction parameters, such as parameters that trigger the initiation of retraction, for example, parameters selected from a group consisting of: lumen flushing (the lumen near optical component 115 has been adequately cleared of blood or other substances that may interfere with image generation); receiving an indication signal from syringe 20 (e.g., a signal indicating that sufficient flushing fluid has been delivered); changes in collected image data (e.g., detecting changes in the image based on collected image data, which are associated with appropriate drainage of blood from around optical component 115); and combinations of one or more of these. In some embodiments, algorithm 51 is configured to adjust imaging system 10 configuration parameters associated with imaging probe 100, such as when algorithm 51 identifies (e.g., automatically identified via RF or other embedded ID) the attached imaging probe 100 and adjusts imaging system 10 parameters (e.g., arm path length parameters, dispersion parameters, and / or other parameters as listed above).

[0129] Imaging system 10 may include one or more interconnecting cables: bus 58 as shown. Bus 58 may operatively connect rotating component 500 to console 50, retractable component 800 to console 50, and / or (e.g., by connecting patient interface unit 200 to console 50) rotating component 500 to retractable component 800. Bus 58 may include one or more optical fiber transmission fibers, electrical transmission cables, fluid conduits, and combinations thereof. In some embodiments, bus 58 includes at least an optical fiber transmission fiber that optically couples rotating component 500 to imaging component 300 of console 50. Additionally or alternatively, bus 58 includes at least power and / or data transmission cables that transmit power and / or power information to retractable component 800.

[0130] User interface 55 may include output 56 and input 57. Output 56 may include one or more outputs selected from the group consisting of: a screen; indicator lights; haptic transducers, such as vibration transducers; speakers; output signals to be received by an external device, such as wireless signals; and combinations thereof. Input 57 may include inputs selected from the group consisting of: buttons; two or more buttons; touchscreens; mice; input signals, such as wireless signals received from an external device; and combinations thereof. In some embodiments, output 56 and / or input 57 are integrated into either or both of patient interface unit 200, and / or rotation component 500 and retraction component 800.

[0131] The second imaging device 15 may include imaging devices, such as one or more imaging devices selected from the group consisting of: X-rays; fluorescein microscopes, such as single-plane or biplane fluorescein microscopes; CT scanners; MRI scanners; PET scanners; ultrasound imagers; and combinations of one or more of these. In some embodiments, the second imaging device 15 includes means configured to perform rotational angiography.

[0132] Treatment device 16 may include occlusion treatment or other treatment devices selected from the group consisting of: balloon catheters configured and positioned to dilate stenosis or other narrowing of the blood vessel; drug-eluting balloons; aspiration catheters; ultrasonic decomposition devices; atherosclerotic resection devices; thrombus removal devices, such as stent thrombectomy devices; Trevo TM Solitaire (stent retrieval device) TM Stent retrieval device; Revive TM Stent retrieval device; Eric TM Lazarus stent retrieval device TM Stent thrombectomy device; stent delivery catheter; micro-invasive implant; embolization system; WEB TM Embolization system; LunaTM Embolization system; Medina TM Embolization systems; and combinations of one or more of these. In some embodiments, the imaging probe 100 is configured to collect data related to the treatment device 16 (e.g., the location, orientation, and / or other configuration data of the treatment device 16) after the treatment device 16 has been inserted into the patient.

[0133] Syringe 20 may include a powered syringe, a syringe pump, a peristaltic pump, or other fluid delivery device configured to inject a contrast agent (such as a radiopaque contrast agent) and / or other fluids. In some embodiments, syringe 20 is configured to deliver a contrast agent and / or other fluids (e.g., contrast agent, saline, and / or dextran). In some embodiments, syringe 20 delivers fluids during a flushing procedure as described below. In some embodiments, syringe 20 delivers the contrast agent or other fluids through a delivery conduit 80 with an ID between 5 Fr and 9 Fr, an ID between 0.53” and 0.70”, or an ID between 0.0165” and 0.027”. In some embodiments, the contrast agent or other fluids are delivered through a delivery conduit as small as 4 Fr (e.g., for distal injection). In some embodiments, syringe 20 delivers the contrast agent and / or other fluids through the lumen of one or more delivery conduits 80, while one or more smaller delivery conduits 80 are also located within the lumen. In some embodiments, the syringe 20 is configured to deliver two different fluids simultaneously and / or sequentially, such as a first fluid delivered from a first reservoir and containing a first concentration of contrast agent, and a second fluid delivered from a second reservoir and containing less or no contrast agent.

[0134] Injection 21 may include a fluid selected from the group consisting of: optically transparent materials; saline; visualization materials; contrast agents; dextran; ultrasound-reflective materials; magnetic materials; and combinations thereof. Injection 21 may include contrast agents and saline. Injection 21 may include at least 20% contrast agent. During image data acquisition, a flushing procedure may be performed, such as by delivering one or more fluids: injection 21 (e.g., propelled by syringe 20 or other fluid delivery device), to remove blood or other slightly opaque materials (hereinafter opaque materials) near the optical component 115 (e.g., to remove opaque materials between the optical component 115 and the delivery catheter and / or between the optical component 115 and the blood vessel wall), such as to allow light distributed from the optical component 115 to reach all tissues and other objects to be imaged and to be reflected back from them. In these flushing embodiments, injection 21 may include optically transparent materials, such as saline. Injection 21 may include one or more visualization materials as described below.

[0135] As an alternative to its use in the rinsing procedure or otherwise, the injection 21 may include materials configured to be observed by the second imaging device 15, such as when the injection 21 includes contrast agent materials configured to be observed by the second imaging device 15 including a fluorescein or other X-ray device; ultrasonic reflective materials configured to be observed by the second imaging device 15 including an ultrasound imager; and / or magnetic materials configured to be observed by the second imaging device 15 including an MRI.

[0136] Implant 31 may include one or more implants (e.g., temporary or long-term implants) for treating vascular occlusion or aneurysm. In some embodiments, implant 31 includes one or more implants selected from the group consisting of: drainage devices; pipelines. TM Surpass TM Drainage device; embolization coil; stent; Wingspan TM Stents; covered stents; aneurysm treatment implants; and combinations of one or more of these.

[0137] The implant delivery device 30 may include a catheter or other tool for delivering the implant 31, such as when the implant 31 includes a self-expanding or balloon-expandable portion. In some embodiments, the imaging system 10 includes an imaging probe 100, one or more implants 31, and / or one or more implant delivery devices 30. In some embodiments, the imaging probe 100 is configured to collect data related to the implant 31 and / or the implant delivery device 30 (e.g., anatomical location, orientation, and / or other configuration data of the implant 31 and / or the implant delivery device 30) after the implant 31 and / or the implant delivery device 30 has been inserted into the patient.

[0138] In some embodiments, one or more system components (such as console 50, delivery catheter 80, imaging probe 100, patient interface) unitThe device 200, rotating assembly 500, retracting assembly 800, treatment device 16, syringe 20, and / or implant delivery device 30 further include one or more functional elements (hereinafter referred to as "functional elements"), such as functional elements 59, 89, 199, 299, 599, 899, 99a, 99b, and / or 99c, respectively. Each functional element may include at least two functional elements. Each functional element may include one or more elements selected from the group consisting of: sensors; transducers; and combinations thereof. Functional elements may include sensors configured to generate signals. Functional elements may include sensors selected from the group consisting of: physiological sensors; pressure sensors; strain gauges; position sensors; GPS sensors; accelerometers; temperature sensors; magnetic sensors; chemical sensors; biochemical sensors; protein sensors; flow sensors, such as ultrasonic flow sensors; gas detection sensors, such as ultrasonic bubble detectors; sound sensors, such as ultrasonic sensors; and combinations thereof. The sensor may include physiological sensors selected from the group consisting of: pressure sensors, such as blood pressure sensors; blood gas sensors; flow sensors, such as blood flow sensors; temperature sensors, such as blood or other tissue temperature sensors; and combinations thereof. The sensor may include a position sensor configured to generate a signal relating to a vascular pathway geometry (e.g., a 2D or 3D vascular pathway geometry). The sensor may include a magnetic sensor. The sensor may include a flow sensor. The system may further include an algorithm configured to process the signals generated by sensor-based functional elements. Each functional element may include one or more transducers. Each functional element may include one or more transducers selected from the group consisting of: heating elements, such as heating elements configured to deliver sufficient heat to ablate tissue; cooling elements, such as cooling elements configured to deliver cryogenic energy to ablate tissue; acoustic transducers, such as ultrasonic transducers; vibration transducers; and combinations thereof.

[0139] In some embodiments, the imaging probe 100 includes a “bubble handling” mechanism, such as a fluid pressurizing element (FPE) 1500, for example, to prevent or at least reduce the presence of bubbles near the optical component 115, as described in detail herein. The FPE 1500 may be configured to generate a pressure differential within a volume of gel 180 and / or otherwise increase the pressure of one or more volumes of gel 180. The FPE 1500 may include a distal end positioned relative to a proximal end near the optical component 115. In some embodiments, the FPE 1500 is configured to increase the pressure within a volume of gel 180 near the optical component 115 and / or generate a pressure differential within that volume of gel. Additionally or alternatively, the FPE 1500 may generate a flow of gel 180 (e.g., a flow of gel 180 comprising one or more bubbles, such as by moving the bubbles away from the optical component 115). FPE 1500 may include a protrusion extending from optical core 110 that increases the pressure of gel 180 as FPE 1500 rotates (via rotation of optical core 110). Alternatively or additionally, FPE 1500 may include a pump, pressurized container, and / or other pressurization source (“pump” herein) fluidly attached to one or more cavities (e.g., cavity 1205 of shaft 120) to increase the pressure of gel 180, for example, intermittently and as required by system 10.

[0140] like Figure 1AAs shown, one or more bubbles B may be present within the gel 180. For example, as the optical core 110 and optical assembly 115 rotate within the gel 180, bubbles B may form, for example, via cavitation and / or other bubble formation anomalies as described above. Additionally or alternatively, one or more bubbles B may (already) be present within the gel 180, for example, as a result of the manufacturing process of the imaging probe 100. In operation, bubbles B near the optical assembly 115 may cause adverse imaging artifacts and / or other imaging problems. The FPE 1500 may be constructed and arranged to prevent or at least reduce bubble B formation, reduce the expansion of one or more bubbles B, reduce the size of one or more bubbles B, and / or cause one or more bubbles to move away from the optical assembly 115. Under initial startup conditions (e.g., when the FPE 1500 has just begun to rotate), the pressure of the gel 180 on the distal side of the FPE 1500 increases, causing bubbles on the distal side of the FPE 1500 to move distally and compress due to the increased pressure. Bubbles on the proximal side of the FPE 1500 initially move toward the FPE 1500 (as fluid is moving to fill the space created by the compressed bubbles), but stop moving once the equilibrium pressure gradient is reached. In some embodiments, the FPE 1500 is configured to manipulate (e.g., propel) the gel 180, for example, to create a high-pressure region HP (e.g., a volume of gel 180 near the optical component 115) around the optical component 115 and a low-pressure region LP (e.g., a volume of gel 180 near the optical component 115) on the proximal side of the FPE 1500.

[0141] In some embodiments, one or more bubbles B may be trapped distal to the high-pressure region HP; however, the FPE 1500 is configured and arranged to manipulate the gel 180 near the optical component 115, for example, to prevent any bubbles B from being trapped near the component 115 (e.g., distally trapped bubbles B do not migrate toward the optical component 115). Additionally or alternatively, the increased pressure of the high-pressure region HP may cause a reduction in the size of any existing bubbles B near the optical component 115 (e.g., compression of any bubbles B within the high-pressure region HP), and / or the increased pressure may prevent the formation of new bubbles B. In some embodiments, the high-pressure region HP generated by the FPE 1500 includes a pressure of at least 3.6 psi (e.g., at least about 0.25 atmospheres), such as at least 5 psi, at least 10 psi, at least 15 psi, at least 20 psi, at least 30 psi, and / or at least 40 psi. In some embodiments, the FPE 1500 generates a pressure of at least 75 psi, at least 100 psi, at least 125 psi, and / or at least 150 psi in the region HP. In some embodiments, the high-pressure zone HP includes a pressure at least 5 psi higher than the low-pressure zone LP, such as at least 10 psi, at least 20 psi, and / or at least 30 psi higher than the low-pressure zone LP. In some embodiments, each bubble B undergoes two or three times the compression (i.e., 1 / 2 or 1 / 3 of its original size) under the high-pressure conditions of the high-pressure zone HP.

[0142] In some embodiments, gel 180 comprises a low-viscosity fluid, such as a shear-thinning fluid with a low initial viscosity, thereby reducing the likelihood of bubble B forming. For example, gel 180 may comprise a viscosity of 1000 centipoise or less. Additionally or alternatively, gel 180 may comprise a high surface tension, such as a surface tension of at least 40 dynes / cm, similarly reducing the likelihood of bubble B forming.

[0143] In some embodiments, gel 180 is pressurized by a pump (e.g., intermittently pressurized to a pressure at or above atmospheric pressure), such as when a pump is pressurized within the lumen 1205, for example, via a pump fluidly connected to the lumen 1205 and located within the console 50 or patient interface unit 200 (e.g., FPE 1500 includes this pump fluidly attached to the lumen 1205 but located outside the lumen). In some embodiments, gel 180 is pressurized by an external source, and FPE 1500 is constructed and arranged to generate a pressure differential within gel 180 (e.g., when rotated) in addition to the pressure applied by a separate pump. Intermittent pressurization (e.g., via an external pump or via rotation of FPE 1500) can provide numerous advantages, such as preventing an increase in dissolved gases in gel 180, which would be caused by a constant applied pressure, as described herein.

[0144] In some embodiments, the FPE 1500 includes a helical protrusion extending radially from the optical core 110, the helical protrusion being configured to increase the pressure of the gel 180 and / or generate a pressure differential within the gel 180 when the optical core 110 is rotated, as referenced below. Figure 2 As described herein. In some embodiments, the FPE 1500 includes one or more protrusions extending radially from the optical core 110, which or these protrusions are configured to generate a pressure differential in the gel 180 when the optical core 110 is rotated, as described below with reference to FIG3. In some embodiments, the FPE 1500 includes a pump, a pressurized container, and / or other pressurization source (hereinafter referred to as "pump"), such as a fluid conduit fluidly attached to the pump at a proximal end and entering the cavity 1205 near the optical assembly 115, as described below with reference to Figure 4 As described.

[0145] In some embodiments, the FPE 1500 is configured to operate intermittently, such as by intermittently increasing the pressure of the gel 180, or by intermittently generating a pressure difference within the gel 180. For example, the FPE 1500 may include one or more protrusions extending radially from the optical core 110, which or these protrusions are configured to generate a pressure difference in the gel 180 only when the optical core 110 is rotated, as described below. Figure 4A As described. In these embodiments, when the FPE 1500 is not operating (e.g., not rotating), the pressure of the gel 180 can be normalized, for example, reaching a pressure below the pressure of the high-pressure region HP when the FPE 1500 is operating (e.g., rotating). Intermittent pressurization can be implemented to prevent an increase in dissolved gases in the gel 180. In some embodiments, the FPE 1500 is configured to operate continuously only for limited time periods (e.g., discrete time periods not exceeding 2 minutes each time, such as not exceeding 30 seconds or 5 seconds) (e.g., intermittently pressurizing the gel 180 to prevent undesirable dissolved gases in the gel 180).

[0146] Now for reference Figure 2 and Figure 2A The diagrams show schematic representations of the distal portions of the imaging probe and delivery conduit, consistent with the concept of this invention, and enlarged views of the components within circle M2. The imaging probe 100 and delivery conduit 80 may have the same features as described above. Figure 1 and Figure 1A The imaging probe 100 and delivery conduit 80 are described as having similar construction and arrangement. Figures 2 to 2A In the embodiment shown, the fluid pressurization mechanism FPE 1500 is illustrated. S Includes spiral protrusions extending radially from the optical core 110. During operation, as the optical core 110 rotates, the FPE 1500... S Consistent rotation, thus achieving FPE 1500S Fluid flow is generated nearby, and within gel 180 (e.g., in FPE 1500). S The above creates a pressure gradient. See below for reference. Figures 2B to 2C Modeling an example describing fluid flow dynamics.

[0147] In some embodiments, FPE 1500 S This includes a helical coil (such as a spring or other winding) attached along a portion of the length of the optical core 110 (e.g., around the core 110). FPE 1500 S It can be adhered to the optical core 110, for example, via glue or another adhesive. In some embodiments, FPE 1500 S Molded on and / or molded with the core 110, formed in the core 110 (e.g., via a material removal process), fused to the core 110, and / or otherwise manufactured with or adhered to the core 110. In some embodiments, FPE 1500 S Materials selected from the group consisting of: metals; plastics; stainless steel; nickel-titanium alloys; nylon; polyetheretherketone (PEEK); polyimide; and combinations thereof. In some embodiments, FPE 1500 S It can be formed directly on the optical core 110, for example, using deposition techniques and / or 3D printing techniques. In some embodiments, a selectively curable material is applied to the optical core 110 and cured in a spiral pattern to form FPE 1500. S For example, a high-strength UV-curable adhesive can be applied to the surface of the optical core 110 and selectively cured using a rotating, focused UV beam. In some embodiments, FPE 1500 S This could include being selected to minimize FPE 1500 when a pressure gradient is applied. S Deformed materials. For example, during rotation, a pressure gradient appears in FPE 1500. S Along its entire length, to prevent deformation, the shorter FPE 1500... S The longer FPE 1500 S A stiffer material is needed, which is configured to produce the same pressure gradient.

[0148] FPE 1500 S Including radial height: height H1, which is from the surface of optical core 110 to FPE 1500. S The distance from the outer edge. The optical core 110 includes a diameter D1. The inner cavity 1205 of the shaft 120 includes an inner diameter D2. In some embodiments, diameters D1 and D2 vary along the length of the probe 100, and the following dimensions relate to segments of the probe 100, such as... Figure 2A The distal segment shown (e.g., the proximal segment of optical component 115 and the segment adjacent to that optical component). Probe 100 may include FPE 1500. S (For example, FPE1500) S The clearance C1 between the outer diameter of the shaft (D1) and the inner wall of the shaft 120. The clearance C1 is related to both the difference between diameters D1 and D2, and the FPE1500. S The height H1 is related to such that C1 is equal to half the difference between D1 and D2 minus H1. In some embodiments, the gap C1 includes a gap of no more than 100 μm (e.g., no more than 75 μm, e.g., between 10 μm and 75 μm). In some embodiments, the height H1 includes a height between 5% and 95% of half the difference between D1 and D2 (e.g., a height H1 occupying at least 5% and / or no more than 95% of the space between the outer surface of core 110 and the inner wall of shaft 120). In some embodiments, the optimal height H1 depends on the following factors: the viscosity of the damping fluid (e.g., the viscosity of gel 180); the desired rotational rate of optical core 110; the desired pressure gradient; and / or FPE 1500. S The gap between the shaft 120 and the inner wall (e.g., a tighter gap generates higher pressure). In some embodiments, FPE 1500 S The coil profile includes a width W1 as shown in the figure. Width W1 can range from 1% to 95% of the diameter D1. FPE 1500 S It may also include a spacing P1 as shown in the figure. Spacing P1 may include a gap such that the interval between adjacent coils is 0.5 to 20 times the diameter D1. In some embodiments, adjacent coils do not contact each other. In some embodiments, spacing P1 is along FPE 1500. S The length is uniform. In some embodiments, the spacing P1 may include a spacing between 0.2 mm and 1.2 mm, such as a spacing of approximately 0.5 mm or 1 mm. In some embodiments, the length of the FPE1500S and / or the spacing P1 may be selected to achieve the desired pressure generated when the optical core 110 rotates.

[0149] In some embodiments, gel 180 includes, for example, the above reference. Figure 1 The described high-viscosity, shear-thinning fluid. In some embodiments, the maximum functional gap C1 (e.g., the maximum gap C1, which is permissible, such that FPE 1500) S The rotation (generating sufficient fluid pressure within the inner cavity 1205) is proportional to the viscosity of the gel 180. For example, the higher the viscosity of the gel 180, the larger the maximum gap C1. In some embodiments, the gap C1 is proportional to the viscosity of the FPE 1500 as described above. SThe pressure difference generated within gel 180 is proportional. For example, the smaller the gap C1, the greater the pressure difference that can be generated. In some embodiments, gap C1 and height H1 are minimized to limit turbulence, recirculation, and / or other adverse fluid flows near optical core 110. In some embodiments, gel 180 comprises a Newtonian (non-shear-thinning) fluid. Dimensions C1, H1, D1, and D2 can be optimized for different properties of gel 180.

[0150] In some embodiments, FPE 1500 S Includes a covering (not shown). The covering may include a sheath, such as heat shrink tubing, and / or a coating applied or sprayed onto it. The covering may be configured to improve FPE 1500. S Integration with optical core 110, and / or control of FPE 1500 S The dimensions (e.g., to fit FPE 1500) S It is held tightly to the optical core 110, for example, to limit unfavorable variations in height H1. Additionally or alternatively, the cover can be configured to modify the optical core 110 and FPE 1500. S The surface properties of one or both of them. In some embodiments, the covering includes a material that does not significantly affect the surface properties of FPE 1500. S The thickness of the material to provide fluid propulsion and / or other fluid pressurization (“fluid pressurization” in this document) performance. Alternatively or additionally, FPE 1500 S It can be constructed and arranged such that dimensions C1, H1, and D1 are optimal after the covering is applied.

[0151] In some embodiments, by FPE 1500 S The rotation of the shaft causes pressure on the gel 180 within the cavity 1205, applying a functional torsional shear force to the inner wall of the cavity 1205. The shaft 120 may include a torsional resistance greater than the functional torsional shear force applied by the gel 180. In some embodiments, the gel 180 applies a torque of approximately 0.004 N-cm, and the shaft 120 includes a torsional resistance of at least 0.01 N-cm (e.g., 0.03 N-cm). Additionally or alternatively, as the optical core 110 rotates, the FPE 1500... S A “winding” stress can be applied to the optical core 110, thereby driving the FPE 1500 within the gel 180. S Optical core 110 can be constructed and arranged so as not to be affected by the core 110 and FPE1500. S The adverse effects of shear stress caused by rotation within gel 180 and shear stress caused by pull-back motion within gel 180 (e.g., failure to break or other failure). In some embodiments, FPE 1500 SThe additional winding stress on the optical core 110 caused by this stress acts as a NURD reduction mechanism (similar to the NURD reduction caused by the gel 180), as described in the applicant’s co-pending international PCT patent application serial number PCT / US2018 / 062766 entitled “Imaging System”, filed on November 28, 2018.

[0152] For further reference Figure 2B and Figure 2C The diagrams show schematic representations of the distal portion of an imaging probe, illustrating fluid flow patterns and fluid flow simulations, consistent with the concept of this invention. The movement of the gel 180 is... Figure 2B The fluid flow arrows FF and Figure 2C Path FP P and FP D Description. Optical core 110 and FPE 1500 S Described as being associated with FPE1500 S The top edge rotates into the page and rotates. In addition to the axial motion shown, the fluid flow also includes... Figure 2C The rotational component is shown. At least the distal portion of the distal end 1209 and / or shaft 120 can be sealed, for example, when the distal end 119 includes a cap or plug configured as a sealing element: Figure 2B The plug 1209a shown is used. FPE 1500 is shown in the figure. S The rotation causes fluid flow towards the high-pressure region HP in the distal direction near the optical core 110. As the pressure within the high-pressure region HP increases to match the pressure of the distal fluid flow, a closed-loop recirculation mode appears as shown in the figure. (From FPE 1500) S Fluid advancing distally encounters pressure within the high-pressure region HP and is redirected proximally along the surface of cavity 1205 (e.g., along the path of least resistance). This fluid flow pattern creates a "dead head" pressure profile (e.g., no net fluid flow), thereby maintaining pressure along FPE 1500. S The pressure gradient from the low-pressure region LP to the high-pressure region HP. For example... Figure 2C As shown, the fluid path FP D The fluid flow is depicted near the optical core 110 and towards the high-pressure region HP. Fluid path FP P The fluid flow near the surface of the inner cavity 1205 toward the low-pressure region LP is depicted.

[0153] Now for reference Figure 3A and Figure 3B The diagram shows a schematic representation of the distal portion of two imaging probes including a fluid propulsion element, consistent with the concept of this invention. Figure 3AThe distal portion of the imaging probe 100a is shown, including the quick-change distal end 119. RX . Figure 3B The distal portion of the imaging probe 100b is shown, which includes the spring end 119. S . Figure 3A and Figure 3B The imaging probes 100a and 100b may include similar components and have the same features as described above. Figure 1 and Figure 1A The imaging probe 100 has a similar structure and arrangement. The optical assembly 115 may include a lens assembly: assembly 1151, which is optically and physically coupled to the distal end of the optical core 110. Lens assembly 1151 may include a GRIN lens, which includes a beveled distal end. The beveled distal end of lens assembly 1151 may include a total internal reflection surface. An elongated tube, i.e., tube 1154, at least surrounds the distal portion of the optical core 110 (lens assembly 1151) and a sealing element (plug 1153) (e.g., similar to...). Figure 2B (The sealing element of the plug 1209a). The tube 1154 may include a heat-shrinkable material. The tube 1154 may include PET. At least a portion of the tube 1154 may be adhesively or otherwise adhered to at least a portion of the lens assembly 1151, the optical core 110, and / or the plug 1153. The plug 1153 is configured to prevent and / or limit the outflow of gel 180 into the cavity formed between the lens assembly 1151 and the plug 1153: the space 1152 shown. The space 1152 may be filled with air and / or one or more other fluids. The fluid within the space 1152 may be configured to provide desired optical properties between the lens assembly 1151 and the fluid (e.g., providing a glass-air interface). The optical core 110 may include a support element 1102. The support element 1102 may include a torque line positioned proximal to the optical assembly 115. The support element 1102 may be configured to reinforce the distal portion of the optical core 110, for example, to provide rotational reinforcement to the optical core 110.

[0154] In some embodiments, the FPE 1500 includes two fluid propulsion elements, such as Figure 3A and Figure 3B The FPE1500 shown S1 and 1500 S2 Distal FPE 1500 S1 It can be configured to generate a pressure gradient on optical component 115 as described herein. Additionally, the proximal FPE 1500 S2 It can be configured to prevent or otherwise minimize the proximal migration of gel 180 (e.g., beyond FPE 1500). S2 ) and / or prevent FPE 1500 S1Nearby cavitation (e.g., priming with gel 180) FPE 1500 S1 To prevent in FPE 1500 S1 Bubbles form nearby). FPE 1500 S2 It can be positioned near the proximal end of the gel 180 (e.g., near the location within the shaft 120 where the gel 180 is inserted from the distal end of the shaft 120 during manufacturing).

[0155] Now for reference Figure 4 and Figure 4A The diagrams show schematics of the distal portion of the imaging probe and delivery conduit, which are consistent with the concept of this invention, and enlarged views of the components within circle M3. Figure 4 and Figure 4A The imaging probe 100 may include similar components and has the same features as described above. Figure 1 The imaging probe 100 has a similar structure and arrangement. Figure 4 and Figure 4A The imaging probe 100 includes a pressurizing element with a propeller-like structure, FPE 1500. P FPE 1500 P It may include one or more radial protrusions 1501 extending from the optical core 110. The protrusions 1501 include profiles configured to propel fluid when the optical core 110 rotates, similar to propeller blades. As described above, FPE 1500 P It can be configured to generate a pressure gradient within gel 180.

[0156] Now for reference Figure 5 and Figure 5A The diagrams show schematics of the distal portion of the imaging probe and delivery conduit, which are consistent with the concept of this invention, as well as enlarged views of the components within circle M4. Figure 5 and Figure 5A The imaging probe 100 may include similar components and has the same features as described above. Figure 1 The imaging probe 100 has a similar structure and arrangement. Figure 5 and Figure 5A The imaging probe 100 includes a pressurization element, which includes a pump and an FPE 1500. PS FPE1500 PS It may include a fluid cavity 1502 having an outlet port 1503 that opens into the cavity 1205 near the optical component 115. The cavity 1205 may be fluidly attached to a pump (not shown), but for example, is... Figure 1 The pump is located within the console 50. The pump can be configured to operate via FPE1500 before, during, and / or after the imaging procedure. PSApply pressure to the gel at 180°. FPE 1500 PS It may further include a fluid restricting element: valve 1504. Valve 1504 is shown positioned proximal to outlet port 1503 within cavity 1205. Valve 1504 can be configured to restrict the proximal flow of fluid (e.g., gel 180) within cavity 1205, such that FPE 1500 PS An increased pressure on gel 180 can be generated at a distal location of valve 1504. Valve 1504 can be configured to allow air and / or other gases (e.g., bubble B as described herein) to pass through, while simultaneously restricting the passage of gel 180 (e.g., due to the viscosity and / or molecular size of gel 180). FPE 1500 PS It can be configured as described in the reference above. Figure 1 and Figure 1A The pressure gradient described is generated within the gel 180.

[0157] Now for reference Figure 6A , Figure 6B and Figure 6C This illustrates a cross-sectional view of the distal portion of an optical probe consistent with the concept of this invention. The imaging probe 100 may have the same features as described above. Figure 1 and Figure 1A The imaging probe 100 described has a similar construction and arrangement. In some embodiments, the optical core 110 is configured to retract and advance within the axis 120, as... Figures 6A to 6C As shown in the diagram. The optical core 110 can be retracted via a linkage 856, which is operatively attached to the proximal portion of the optical core 110 (as described above). Figure 1 (As shown in the diagram). A fluid pressurizing element optically coupled to the optical core 110 may include, for example, the element described in the reference above. Figures 2 to 3B The described spring-type element, FPE 1500 S FPE1500 S It can be configured to generate a pressure gradient within the gel 180, such as that described above, from a low-pressure region LP to a high-pressure region HP. In some embodiments, when the optical core 110 retracts within the shaft 120, the retraction may induce voids within the gel 180 (e.g., one or more bubbles formed due to the pressure drop caused by the retraction of the optical core 110). FPE 1500 S It can be configured to minimize the generation of these voids by creating a pressure gradient within the gel 180 during the rotation and retraction of the optical core 110. Additionally or alternatively, FPE 1500 S It can be configured to generate a prime mover that is configured to longitudinally drive (e.g., translate proximally and / or distally) at least the distal end of the optical core 110 within the cavity 1205 of the shaft 120.

[0158] FPE 1500 S It can be configured to generate kinetic and pressure gradients within the gel 180, thereby causing one or more outcome scenarios, such as Figures 6A to 6C As shown in [the document]. Figure 6A In the middle, as the optical core 110 rotates along the first direction (causing FPE 1500... S The gel is pushed 180 degrees to the distal side, and the retraction force F R A pressure gradient is applied to the optical core 110, creating a pressure gradient from the low-pressure region LP to the high-pressure region HP. The optical core 110 can be held by a holding force F. H (For example, see the reference above) Figure 1 The force applied from the retractable assembly 800 (described) keeps the optical core 110 in place. In this state, the optical core 110 does not travel longitudinally within the axis 120 (e.g., proximal and / or distal).

[0159] like Figure 6B As shown, when the holding force F is removed H At that time, force F R The retraction assembly 800 retracts at least the distal portion of the optical core 110 back into the shaft 120. In some embodiments, the retraction assembly 800 also applies a retraction force to the optical core 110. Force F R It can be configured to retract within the shaft 120 via the auxiliary optical core 110, limiting the stress applied to the optical core 110 when a retraction force is applied from the proximal portion.

[0160] In some embodiments, such as Figure 6C As shown, optical core 110 (and FPE 1500) S It can be rotated in a second direction (e.g., opposite to the first direction) such that FPE 1500 S Driven proximally by the gel 180, thereby amplifying the forward force F A Force F is applied to the optical core 110. In some embodiments, the retraction assembly 800 may apply a forward force to the proximal portion of the optical core 110. A It can be configured to apply thrust to the proximal portion when the retraction assembly 800 applies force F A (Tension) is applied to the distal portion of the optical core 110 to restrict and / or prevent the optical core 110 from knotting within the shaft 120.

[0161] Now for reference Figure 7 The image shows a cross-sectional view of a segment of an imaging probe comprising an axis having a multi-component structure, consistent with the inventive concept. The imaging probe 100 of the inventive concept may include an axis configured to have multiple components (e.g., Figure 7(Components of shaft 120 shown). Shaft 120 may include at least a first (proximal) portion: tube 121, which is fixedly attached to a second (distal) portion: window 130 via a connector 125. Tube 121 may include an elongated hollow member, such as a hypotube (e.g., a metal tube that may include one or more engineered features along its length). In some embodiments, tube 121 includes a hypotube including a helical cut along at least a portion of its length. In some embodiments, tube 121 includes a nickel-titanium alloy (e.g., Nitinol). In some embodiments, tube 121 includes a plastic material, such as polyimide or PEEK. In some embodiments, window 130 includes a transparent elongated hollow member, such as the one referenced above. Figure 1 As described.

[0162] The connector 125 may include at least a distal portion of the tube 121 and at least a proximal portion of the window 130. The distal portion of the tube 121 may include a tapered portion: a tapered section 1211. The tapered section 1211 may be configured such that the outer diameter of the tube 121 decreases from the proximal end of the tapered section 1211 to the distal end of the tapered section 1211. The tube 121 includes an inner lumen 1215 passing through it. An elongated section: the tube 123 is partially inserted into the inner lumen 1215 of the tube 121. The tube 123 may include an outer diameter approximately equal to the diameter of the inner lumen 1215. In some embodiments, the tube 123 includes an outer diameter slightly larger than the diameter of the inner lumen 1215 (e.g., such that the tube 123 can be press-fitted into the inner lumen 1215), or the tube 123 includes a diameter equal to or slightly smaller than the diameter of the inner lumen 1215 (e.g., to provide space for an adhesive between the tube 125 and the tube 121). The tube 123 includes an inner lumen 1235 passing through it. In some embodiments, the cavity 1235 includes a diameter larger than the outer diameter of the optical core 110 (e.g., such that the optical core 110 can be slidably positioned therethrough). Additionally or alternatively, the cavity 1235 may include a diameter smaller than FPE 1500. S The outer diameter (e.g., pipe 123 includes the inner diameter) makes FPE 1500 S It cannot be shifted proximally beyond tube 123 (e.g., FPE 1500). S Proximal translation resulted in FPE 1500 S The end of the contact tube 123, thereby preventing FPE 1500. S Enter the inner cavity (1235).

[0163] The connector 125 may further include an outer sleeve 122 configured to at least surround the distal portion of tube 121 and at least a portion of tube 123 (e.g., at least a portion of tube 123 extending distally from the inner lumen 1215). The outer sleeve 122 may include a "heat-shrinkable" material (e.g., a material configured to shrink when heat is applied). In these embodiments, the outer sleeve 122 may include a first diameter equal to or greater than the outer diameter of tube 121 (e.g., a pre-shrink diameter) such that tube 121 can be slidably received within the outer sleeve 122. After the outer sleeve 122 is positioned relative to tubes 121 and 123, heat may be applied, causing the outer sleeve 122 to shrink and conform to the outer contours of tubes 121 and 123. Additionally or alternatively, the outer sleeve 122 may include a resilient material. In some embodiments, the outer sleeve 122 may include a resilient material and have an inner diameter less than or equal to the outer diameter of tube 123. In these embodiments, by stretching the outer sleeve 122 to slidably receive the tubes 121 and 123, the outer sleeve 122 can be positioned around the tubes 121 and 123 such that the outer sleeve 122 retracts after positioning to conform to the outer contours of the tubes 121 and 123. In some embodiments, the outer sleeve 122 can be "wound" onto the tubes 121 and 123 such that the outer sleeve 122 is both stretched and conformed as it is wound over the tubes 121 and 123. The outer sleeve 122 may comprise PET.

[0164] The proximal portion of window 130 may include an inwardly projecting radial protrusion 1302. The radial protrusion 1302 may include an inner diameter configured and arranged to match the outer diameters of tubes 123 and 122 (e.g., the outer diameter of tube 122 compressed around tube 123). In some embodiments, window 130 may not include the radial protrusion 1302, and the inner diameter of window 130 may be configured and arranged to match the outer diameters of tubes 123 and 122. In some embodiments, the proximal portion of window 130 slidably receives the distal portions of tubes 122 and 123. The proximal portion of window 130 may further slidably receive at least the distal portion of the tapered portion 1211 of tube 121. Window 130 may be securely attached to tubes 121, 122, and / or 123 via compression and / or adhesive. In some embodiments, the outer surface of the outer sheath 122 may be prepared (e.g., mechanically or chemically) for adhesion to window 130, for example, via chemical primers. In some embodiments, the proximal end of window 130 “contracts” onto tubes 121, 122, and / or 123 to provide a compression fit. In some embodiments, window 130 includes a material configured to contract under tension (e.g., when window 130 is intentionally or unintentionally pulled away from tube 121), such that window 130 compresses onto tubes 121, 122, and / or 123, thereby reinforcing joint 125 under tension. In these embodiments, tubes 121, 122, and / or 123 may include a lower modulus than window 130, such that window 130 compresses more under equal tension than one or more of tubes 121, 122, and / or 123.

[0165] In some embodiments, connector 125 has a maximum outer diameter of not more than 0.02" (e.g., not more than 0.0175", or less than or equal to 0.0155"). In some embodiments, connector 125 has a tensile strength of at least 2N" (e.g., at least 2.6N, at least 5.5N, or at least 6N). In some embodiments, the distal portion of imaging probe 100 (including at least the distal section of connector 125 and tube 121, e.g., the distal 30cm of imaging probe 100) has a minimum bending radius of not more than 5mm" (e.g., not more than 4mm, not more than 3mm, or not more than 2.5mm).

[0166] In some embodiments, the optical core 110 may include two or more layers (e.g., two or more concentric layers), such as core 1105, which may be surrounded by one or more cladding layers: cladding 1106.

[0167] Now for reference Figure 8 The image shows a cross-sectional view of a portion of an imaging probe including a bidirectional fluid propulsion element, consistent with the concept of the present invention. Figure 8The imaging probe 100 may include similar components and has the same characteristics as described herein. Figure 1 The imaging probe 100 has a similar structure and arrangement. Figure 8 The imaging probe 100 includes two fluid propulsion elements: FPE 1500 F and 1500 R In some embodiments, FPE 1500 F It can be positioned at FPE 1500 R Proximal, such as Figure 8 As shown in the image. FPE 1500 F It can be configured, as described herein, to face FPE 1500 when the optical core 110 rotates in the first direction. R Push the gel 180 degrees distally. FPE 1500 R It can be configured to rotate when the optical core 110 also rotates in the first direction (e.g., when FPE1500). F and 1500 R When rotated in the same direction, they propel the gel (180°) toward the FPE 1500 in opposite directions. F Prop the gel 180 proximally. In this way, FPE 1500 F and 1500 R Configured to hold the gel 180 between each other (e.g., creating a confined area of ​​pressurized gel 180 between the two elements). In some embodiments, the FPE 1500 advances and / or retracts within the shaft 120 as the optical core 110 advances and / or retracts. F and 1500 R Configured to propel gel 180 to translate together with optical core 110 (e.g., as FPE translates together with optical core 110, it remains in FPE 1500). F With 1500 R (between). In some embodiments, the rotation of the optical core 110 can be reversed, thereby causing the gel 180 to at least partially detach from the FPE 1500. F With 1500 R The area between them was emptied.

[0168] Now for reference Figure 9A Figure 9 shows a perspective view of the four steps of the process for manufacturing a fluid propulsion element in accordance with the concept of this invention. Figure 9A A tube 1510 (e.g., a polyimide tube) is shown surrounding a mandrel 1520. A helical channel has been cut into the tube 1510 (e.g., laser-cut) (e.g., after the mandrel 1520 has been inserted into the tube 1510). Figure 9BIn this configuration, the mandrel 1520 has been rotated 180°, and a second helical channel has been cut out, thereby dividing the tube 1510 into a first fluid propulsion element FPE1 and a second fluid propulsion element FPE2, both of which surround the mandrel 1520 (e.g., two similar or dissimilar FPEs 1500s). Figure 9C In this process, FPE2 has been removed from mandrel 1520, for example, FPE2 has been peeled off from mandrel 1520. Figure 9D In this process, FPE1 has also been removed from mandrel 1520 (e.g., peeled off or slid away from mandrel 1520). The illustrated process provides for the use of two fluid propulsion elements of the present invention, such as for use with a single optical probe 100 comprising two FPEs 1500s, and / or for use with two optical probes 100, each comprising a single FPE 1500. In this process, each of FPE1 and FPE2 may include matched dimensions, for example, when the coil spacing is equal to the coil width of each FPE. In some embodiments, three or more slits may be formed in tube 1510, for example, to produce three or more FPEs 1500s.

[0169] The above embodiments should be understood as illustrative examples only; further embodiments are contemplated. Any feature described herein with respect to any embodiment may be used alone or in combination with other described features, and may also be used in combination with one or more features of any other embodiment, or any combination of any other embodiment. Furthermore, equivalents and modifications not described above may be employed without departing from the scope of the inventive concept as defined by the appended claims.

Claims

1. An imaging system for a patient, comprising: An imaging probe, comprising: An elongated shaft including a proximal end, a distal portion, and an inner cavity extending between the proximal end and the distal portion; A rotatable optical core, comprising a proximal end and a distal end, wherein at least a portion of the rotatable optical core is positioned within the cavity of the elongated shaft; An optical component, positioned near the distal end of the rotatable optical core, is configured to guide light to the tissue and collect reflected light from the tissue. A damping fluid, positioned between the elongated shaft and the rotatable optical core and configured to reduce uneven rotation of the optical assembly; and A fluid pressurizing element, comprising a helical protrusion extending radially from the rotatable optical core, the fluid pressurizing element being configured to increase the pressure of the damping fluid to reduce the presence of air bubbles near the optical assembly when the rotatable optical core is rotated; and An imaging component is constructed and arranged to be optically coupled to the imaging probe, and the imaging component is configured to emit light into the imaging probe and receive reflected light collected by the optical component; The damping fluid includes a shear-thinning fluid.

2. The system of claim 1, wherein the fluid pressurizing element is configured to reduce bubble formation.

3. The system of claim 1, wherein the fluid pressurizing element is configured to reduce the growth of one or more bubbles.

4. The system of claim 1, wherein the fluid pressurizing element is configured to reduce the size of one or more bubbles.

5. The system of claim 1, wherein the system includes a beam path, and wherein the fluid pressurizing element is configured to propel one or more bubbles to a location away from the beam path.

6. The system of claim 1, wherein the fluid pressurizing element is configured to generate a pressure gradient within the damping fluid.

7. The system of claim 1, wherein the fluid pressurizing element is configured to increase the pressure of the damping fluid over a finite time period.

8. The system of claim 1, wherein the fluid pressurizing element is configured to intermittently increase the pressure of the damping fluid.

9. The system of claim 8, wherein the fluid pressurization element is configured to increase the pressure of the damping fluid only when imaging is occurring.

10. The system of claim 8, wherein the fluid pressurization element is configured to increase the pressure of the damping fluid only when the rotatable optical core is rotated.

11. The system of claim 8, wherein the fluid pressurizing element is configured to increase the pressure of the damping fluid over a discrete time period of no more than two minutes.

12. The system of claim 8, wherein the fluid pressurizing element is configured to increase the pressure of the damping fluid over a discrete time period not exceeding 30 seconds.

13. The system of claim 8, wherein the fluid pressurizing element is configured to increase the pressure of the damping fluid over a discrete time period of no more than five seconds.

14. The system of claim 1, wherein the fluid pressurizing element is configured to generate at least the following pressures of the damping fluid: 3.6 psi; 5.0 psi; 10 psi; 15 psi; 20 psi; 30 psi; and / or 40 psi.

15. The system of claim 1, wherein the fluid pressurizing element is configured to generate at least the following pressures of the damping fluid: 75 psi; 100 psi; 125 psi; and / or 150 psi.

16. The system of claim 1, wherein the fluid pressurizing element is configured to generate a high-pressure region and a low-pressure region within the damping fluid.

17. The system of claim 1, wherein the fluid pressurizing element includes a pressurizing source.

18. The system of claim 17, wherein the pressurization source comprises a pump.

19. The system of claim 17, wherein the fluid pressurizing element further includes a valve configured to allow gas to pass through while restricting the passage of the damping fluid.

20. The system of claim 1, wherein the fluid pressurizing element includes at least one protrusion extending radially from the rotatable optical core.

21. The system of claim 20, wherein the at least one protrusion comprises a plurality of protrusions, each protrusion extending radially from the rotatable optical core.

22. The system of claim 1, wherein the fluid pressurization element comprises a helical coil surrounding the rotatable optical core.

23. The system of claim 22, wherein the helical coil has an equal spacing.

24. The system of claim 1, wherein the fluid pressurizing element comprises an element having a propeller-like configuration.

25. The system of claim 1, wherein the fluid pressurizing element comprises a spring-type element.

26. The system of claim 1, wherein the fluid pressurizing element comprises a first fluid pressurizing element and a second fluid pressurizing element, and wherein the second fluid pressurizing element is positioned near the first fluid pressurizing element.

27. The system of claim 26, wherein the second fluid pressurizing element is configured to trigger the first fluid pressurizing element during rotation.

28. The system of claim 1, wherein the fluid pressurizing element is viscously attached to the rotatable optical core.

29. The system of claim 1, wherein the fluid pressurizing element is molded on and / or molded together with the rotatable optical core.

30. The system of claim 1, wherein the fluid pressurizing element is fused to the rotatable optical core.

31. The system of claim 1, wherein the fluid pressurization element is formed in the rotatable optical core.

32. The system of claim 31, wherein the system is formed on the rotatable optical core via deposition and / or three-dimensional (3D) printing.

33. The system of claim 1, wherein the fluid pressurizing element comprises a material selected from the group consisting of: metals; plastics; stainless steel; nickel-titanium alloys; nylon; polyetheretherketone; polyimide; and combinations thereof.

34. The system of claim 1, wherein the rotatable optical core includes a diameter D1, and the inner cavity of the elongated shaft includes a diameter D2. The fluid pressurizing element extends radially from the rotatable optical core with a height H1, and H1 comprises at least 5% and / or no more than 95% of half the difference between D1 and D2.

35. The system of claim 1, wherein the rotatable optical core includes a diameter D1, wherein the inner cavity of the elongated shaft includes a diameter D2, wherein the fluid pressurizing element extends from the rotatable optical core with a radial height H1, wherein the gap C1 includes half the difference between D1 and D2 minus H1, and wherein the gap C1 includes a length not exceeding 100 µm and / or not exceeding 75 µm.

36. The system of claim 1, wherein the fluid pressurizing element includes a cover.

37. The system of claim 36, wherein the cover comprises elements selected from the group consisting of: a sheath; a heat-shrinkable tube; a coating applied thereto; a coating sprayed thereto; and combinations thereof.

38. The system of claim 1, wherein the fluid pressurizing element is further configured to generate a prime mover, and wherein the prime mover is configured to translate the rotatable optical core.

39. The system of claim 38, wherein the fluid pressurizing element is configured to advance the rotatable optical core when rotated in a first direction and to retract the rotatable optical core when rotated in a second direction opposite to the first direction.

40. The system of claim 1, wherein the damping fluid comprises a non-Newtonian fluid.

41. The system of claim 1, wherein the damping fluid has a static viscosity of at least 500 centipoise.

42. The system of claim 41, wherein the damping fluid has a shear viscosity less than its static viscosity.

43. The system of claim 41, wherein the damping fluid comprises a static viscosity to shear viscosity ratio of at least 1.2:1 and / or no more than 100:

1.

44. The system of claim 1, wherein the damping fluid comprises a first fluid and a second fluid.

45. The system of claim 44, wherein the first fluid comprises a low-viscosity fluid and the second fluid comprises a high-viscosity fluid.

46. ​​The system of claim 1, wherein the damping fluid comprises a low-viscosity fluid configured to reduce bubble formation.

47. The system of claim 46, wherein the damping fluid comprises a fluid with a viscosity not exceeding 1000 centipoise.

48. The system of claim 1, wherein the damping fluid comprises a fluid with high surface tension configured to reduce bubble formation.

49. The system of claim 48, wherein the damping fluid comprises a fluid with a surface tension of at least 40 dynes / cm.

50. The system of claim 1, wherein the imaging probe includes a distal portion with a diameter not exceeding 0.020”.

51. The system of claim 50, wherein the distal portion of the imaging probe comprises a diameter not exceeding 0.016”.

52. The system of claim 1, wherein the imaging probe further includes a sealing element in the distal portion of the elongated shaft.

Images