CN118235301A

CN118235301A - Improved high bandwidth energy source for endovascular lithotripsy via fiber optic transmission

Info

Publication number: CN118235301A
Application number: CN202280073274.6A
Authority: CN
Inventors: 克里斯多佛·A·库克; 杰拉尔德·大卫·巴彻; 卡罗琳·康明斯; 亚历山大·贝斯尼尔; 帕特里克·曼恩
Original assignee: Bolt Medical Co ltd
Current assignee: Bolt Medical Co ltd
Priority date: 2021-10-28
Filing date: 2022-10-25
Publication date: 2024-06-21

Abstract

The catheter system (100) includes a light guide (122A) and a light source (124). The light guide (122A) is configured to selectively receive light energy. The light source (124) generates light energy. The light source (124) is in optical communication with the light guide (122A). The light source may include (i) a seed source (260) that outputs light energy, (ii) a pre-amplifier (262) that receives light energy from the seed source (260), and (iii) an amplifier (264) that receives light energy from the pre-amplifier (262), the pre-amplifier (262) being in optical communication with the seed source (260), the amplifier (264) being in optical communication with the pre-amplifier (262) and the light guide (122A).

Description

Improved high bandwidth energy source for endovascular lithotripsy via fiber optic transmission

RELATED APPLICATIONS

The present application is related to and claims priority from the following applications: U.S. provisional patent application Ser. No. 63/273,065, filed on day 28 at 10 at 2021, and U.S. patent application Ser. No. 17/970,359, filed on day 20 at 2022, filed on even date 17/970, "HIGH BANDWIDTH ENERGY SOURCE FOR IMPROVED TRANSMISSION THROUGH OPTICAL FIBER FOR INTRAVASCULAR LITHOTRIPSY". The contents of U.S. provisional application Ser. No. 63/273,065 and U.S. patent application Ser. No. 17/970,359 are incorporated herein by reference in their entireties to the extent that they are permissible.

Background

Vascular lesions (vascular lesions) within blood vessels (vessels) in vivo may be associated with increased risk of serious adverse events such as myocardial infarction, embolism, deep vein thrombosis, stroke, and the like. It can be challenging for a physician in a clinical setting to treat severe vascular lesions and achieve vascular patency. Vascular lesions may be treated using interventions such as drug therapy, balloon angioplasty, atherectomy, stenting, vascular graft bypass (vascular graft bypass), to name a few. These interventions may not always be ideal or may require subsequent treatment to address the lesion.

Fiber optic delivery with laser pulses to create plasma-induced mechanical pulses (MECHANICAL IMPULSES) on lesions is one method of treating vascular lesions by fragmentation (ablation). Shaping (shaping) the temporal form of the optical pulse makes it possible to reduce the peak power of the pulse below the damage threshold (damage threshold) of the fiber and still transmit the full energy used to generate the mechanical pulse. This increases the amount of energy that can be delivered within a set time interval while minimizing peak laser intensity to remain below the damage threshold of the fiber. However, the nonlinear optical process in bulk fiber (bulk optical fiber) may still attenuate the energy transmission through the fiber. Thus, nonlinear optical processes can limit the peak energy delivered and the ability of the device to rupture lesions.

One of the main problems encountered with using pulses of light energy to create plasma-driven acoustic bubbles (acoustic bubbles) is coupling enough energy into the input end (proximal end) of the fiber or other light guide (light guide) to produce an effective therapeutic effect at the output end (distal end) of the fiber. In developing this technique, damage to the light guide that transmits pulses of light energy in the body is a critical challenge. The factors involved are the Laser Induced Damage Threshold (LIDT) of the light guide interface and the bulk threshold (bulk threshold) of the medium itself. For a12 ns pulse, LIDT of bulk fused silica (bulk fused silica) was 1866J cm ^-2 at 1064 nm. LIDT for a surface may be one tenth or less of 1866J cm ^-2. Surface finish (Surface finish quality) and cleanliness have a significant impact on this number. Since the damage threshold of the light guide surface is well below that of bulk material, the fault typically appears to damage the light guide input (proximal). The amount of energy transmitted through the light guide is then limited by the peak intensity of the pulse on the proximal surface. This limitation is mainly addressed by stretching the energy pulse width over time. This reduces peak power and surface irradiance while maintaining total energy.

Further, recent experiments have shown that for pulses having an approximately gaussian temporal shape, the peak pressure generated by the light pulse is proportional to the peak intensity of the pulse. This means that even though shorter pulses are limited to a lower total energy due to the damage threshold of the transmission medium, they can generate pressure waves similar to longer pulses using significantly less total optical energy. As a result, pressure waves of sufficiently high energy may be generated to disrupt calcified lesions while remaining well below the damage threshold of the light guide.

Even if pulse stretching techniques are used to reduce the peak power of the light guide surface, the peak power is still high enough to induce stimulated brillouin scattering (Stimulated Brillouin scatter, SBS) in the light guide material itself. SBS is a nonlinear process that can occur in optical media at relatively low input power levels. Once the brillouin threshold is reached, the SBS manifests itself by generating counter-propagating Stokes waves (Stokes waves) that carry most of the input power. The interaction of the incoming photons with the refractive index changes moving within the material produces backscattered phonons, i.e. stokes waves. This process removes energy from the input beam. In turn, the counter-propagating wave creates a region of periodic refractive index variation that behaves like a Bragg grating. This causes more forward beam (forward beam) to be back-scattered. This non-linear process causes the total transmitted energy to decrease exponentially with increasing input. As more energy is input, it radically reduces the total energy transmitted.

For the case of the input optical frequency linewidth, Δv _p is narrow compared to the frequency linewidth of brillouin scattering, the unsaturated brillouin gain coefficient G _B0 is given at wavelength λ by the following equation:

Where p ₁₂ is the elastic optical coefficient of the material, ρ is the density of the material, n is the refractive index of the material, V _s is the speed of sound of the vibration, and Δv _B is the brillouin frequency linewidth in the material. The brillouin frequency linewidth in silica is about 135MHz. At λ=1 μm, G _B0＝4.5×10^-9 cm/W. If the input photon beam linewidth Deltav _p is greater than

This directly suggests that one way to reduce the SBS effect is to broaden the Δv _p significantly.

Linewidth (optical bandwidth) is a measure of spectral purity (monochromaticity). Generally, pulsed solid-state lasers with short cavity lengths have characteristically narrow linewidths, on the order of tens of kHz to hundreds of MHz. It is also helpful to consider this in terms of the coherence length given below:

This line width range corresponds to a coherence length of from about several kilometers to 2 meters. This is the range that the laser can interfere with itself and contribute to SBS. The 135MHz brillouin frequency linewidth in silicon dioxide corresponds to a coherence length of about 70 cm. In order to reduce the brillouin gain factor to such an extent that SBS does not affect the optical transmission through the optical fibre, the linewidth needs to be several orders of magnitude larger than the fundamental brillouin frequency linewidth. This will be 13GHz to 30GHz, corresponding to a coherence length of about 7mm to 3 mm. Other energy sources may have bandwidths ranging from 50pm to 69pm, corresponding to 13.25GHz to 18.25GHz at 1064 nm.

SUMMARY

The present invention relates to a catheter system for treating a treatment site (TREATMENT SITE) within or adjacent to a vessel wall or heart valve. In various embodiments, the catheter system includes a light guide and a light source. The light guide is configured to selectively receive light energy. The light source generates light energy. The light source is in optical communication with the light guide. The light source may include (i) a seed source that outputs light energy, (ii) a preamplifier that receives light energy from the seed source, the preamplifier being in optical communication with the seed source, and (iii) an amplifier that receives light energy from the preamplifier, the amplifier being in optical communication with the preamplifier and the light guide.

In some embodiments, the catheter system further comprises a seed controller that controls the seed source.

In certain embodiments, the catheter system further comprises an optical element configured to direct light energy into the light guide.

In various embodiments, the seed source comprises one of a diode laser, a programmable semiconductor laser, a gated fiber laser, and a low power solid state laser.

In some embodiments, the seed source, the pre-amplifier, and the amplifier are free-space coupled within the light source.

In certain embodiments, the seed source is optically coupled to the pre-amplifier by a first coupling light guide and the pre-amplifier is optically coupled to the amplifier by a second coupling light guide.

In various embodiments, the pre-amplifier comprises one of a fiber laser, a solid state laser, a flash lamp, and a diode pumped neodymium doped yttrium aluminum garnet rod (diode pumped neodymium-doped yttrium aluminum gamet rod).

In some embodiments, the amplifier includes one of a fiber laser, a diode pumped solid state laser, a flash lamp, and a high gain stage configured to have a high energy output capability.

In certain embodiments, the amplifier comprises a gain medium comprising one of (i) a neodymium-doped yttrium aluminum garnet rod, (ii) a neodymium-doped yttrium aluminum garnet plate, (iii) a neodymium-doped glass, and (iv) an erbium-doped yttrium lithium fluoride, the gain medium being optically coupled to one of the laser diode stack and the flash lamp.

In various embodiments, the light source includes a collimator that collimates the light energy output by the pre-amplifier, the collimator being in optical communication with the pre-amplifier and the amplifier.

The invention also relates to a catheter system for treating a treatment site within or adjacent to a vessel wall or heart valve. In various embodiments, the catheter system includes a light guide and a light source. The light guide is configured to selectively receive light energy. The light source generates light energy. The light source is in optical communication with the light guide. The light source may include (i) a seed source that outputs light energy, (ii) a linewidth modifier that modifies a linewidth of the light energy output by the seed source, (iii) a preamplifier that receives the light energy from the linewidth modifier, the preamplifier in optical communication with the linewidth modifier, (iv) a collimator that collimates the light energy output by the preamplifier, the collimator in optical communication with the preamplifier, and (v) an amplifier that receives the light energy from the preamplifier, the amplifier in optical communication with the collimator and the light guide.

In some embodiments, the seed source comprises a modulated distributed feedback laser.

In certain embodiments, the seed source comprises a plurality of modulated distributed feedback lasers.

In various embodiments, the plurality of modulated distributed feedback lasers are configured to have a seed offset at the center wavelength that is above and below the amplifier wavelength of the amplifier.

In some embodiments, the seed source is optically coupled to the linewidth modifier through a first coupling light guide.

In certain embodiments, the seed pulse shape of the seed source is controlled at least in part by directly modulating the seed source.

In various embodiments, the seed pulse shape of the seed source is controlled at least in part by the acousto-optic modulator.

In some embodiments, the seed source includes a diode configured to have high spatial coherence and low temporal coherence.

In certain embodiments, the diode is a superluminescent diode.

In various embodiments, the linewidth modifier is a band-limited filter (band-LIMITING FILTER).

In some embodiments, the linewidth modifier is a fiber bragg grating.

In certain embodiments, the seed source and the linewidth modifier work cooperatively to (i) increase the seed linewidth of the seed source, (ii) improve the amplification of the light energy, and (iii) minimize stimulated brillouin scattering in the light guide.

The invention further relates to a catheter system for treating a treatment site within or adjacent to a vessel wall or heart valve. In various embodiments, the catheter system includes a light guide and a light source. The light guide is configured to selectively receive light energy. The light source generates light energy. The light source is in optical communication with the light guide. The light source may include (i) a seed source that outputs light energy, and (ii) an amplifier that receives light energy from the seed source, the amplifier being in optical communication with the seed source and the light guide.

The present invention also relates to a method for treating a treatment site within or adjacent a vessel wall or heart valve, the method comprising providing and/or using any of the catheter systems shown and/or described herein.

This summary is an overview of some of the teachings of the present application and is not intended to be an exclusive or exhaustive treatment of the present subject matter. Further details are found in the detailed description and the appended claims. Other aspects will become apparent to those skilled in the art upon reading and understanding the following detailed description and viewing the accompanying drawings, which form a part thereof, and are not to be taken in a limiting sense. The scope of this document is defined by the appended claims and their legal equivalents.

Brief Description of Drawings

The novel features of this invention, as well as the invention itself (both as to its structure and its operation), will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which like reference characters refer to like parts, and in which:

FIG. 1 is a simplified schematic diagram of one embodiment of a portion of a catheter system having features of the present invention;

FIG. 2 is a simplified schematic diagram of another embodiment of a portion of a catheter system;

FIG. 3 is a simplified schematic diagram of yet another embodiment of a portion of a catheter system; and

Fig. 4 is a simplified schematic diagram of yet another embodiment of a portion of a catheter system.

While the embodiments are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the scope of the present disclosure is not limited to the particular aspects described. On the contrary, the intention is to cover modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Description of the invention

Treatment of vascular lesions (also referred to herein as "treatment sites") may reduce significant adverse events or death in affected subjects. As described herein, a significant adverse event is a significant adverse event that may occur anywhere in the body due to the presence of a vascular lesion. Significant adverse events can include, but are not limited to: a major cardiac adverse event, a major adverse event of the surrounding vasculature or central vasculature, a major adverse event of the brain, a major adverse event of the muscular system, or a major adverse event of any internal organ.

As used herein, the terms "intravascular lesion," "vascular lesion," and "treatment site" are used interchangeably unless otherwise indicated. Intravascular lesions and/or vascular lesions are sometimes referred to herein simply as "lesions". Further, as used herein, the terms "focal position" and "focal spot" may be used interchangeably unless otherwise indicated, and may refer to any position where light energy is focused to a diameter smaller than the initial diameter of the light source.

Those of ordinary skill in the art will realize that the following detailed description of the present invention is illustrative only and is not intended to be in any way limiting. Other embodiments of the invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. Reference will now be made in detail to embodiments of the present invention as illustrated in the accompanying drawings.

In the interest of clarity, not all of the routine features of the implementations described herein are shown and described. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as compliance with application-and business-related constraints, and that these specific goals will vary from one implementation to another and from one developer to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of engineering for those of ordinary skill in the art having the benefit of this disclosure.

The catheter systems disclosed herein may include many different forms. Referring now to fig. 1, a schematic cross-sectional view of a catheter system 100 is shown, according to various embodiments. The catheter system 100 is adapted to apply pressure waves to induce a rupture in one or more treatment sites within or adjacent to a vessel wall of a vessel within a patient's body, or on or adjacent to a heart valve within the patient's body. In the embodiment shown in fig. 1, catheter system 100 may include one or more of catheter 102, light guide bundle (light guide bundle) 122 including one or more light guides 122A (some embodiments described herein include at least a first light guide and a second light guide), handle assembly 128, source manifold 136, fluid pump 138, and system console 101. The system console 101 may include one or more of a multiplexer 123, a light source 124, a power supply 125, a system controller 126, a graphical user interface 127 (also sometimes referred to herein as a "GUI"), and an optical analyzer component 142. Alternatively, catheter system 100 may include more or fewer components than those specifically shown and described in connection with fig. 1.

It should be appreciated that although catheter system 100 is generally described herein as including light guide beam 122 and light source 124, light guide beam 122 includes one or more light guides 122A. In some alternative embodiments, catheter system 100 may include an energy director bundle that includes different types of energy directors and/or different types of energy sources.

In various embodiments, the catheter 102 is configured to be moved to a treatment site 106 within a vessel wall 108A of a vessel 108 or adjacent to a vessel wall 108A of a vessel 108 within a body 107 of a patient 109. For example, the treatment site 106 may include one or more vascular lesions 106A, such as calcified vascular lesions. Additionally, or in the alternative, the treatment site 106 may include a vascular lesion 106A, such as a fibrovascular lesion. Still alternatively, in some embodiments, the catheter 102 may be used within a heart valve or at a treatment site 106 adjacent to the heart valve within the body 107 of the patient 109.

The catheter 102 may include an expandable balloon 104 (sometimes referred to herein simply as a "balloon"), a catheter shaft 110, and a guidewire 112. Balloon 104 may be coupled to catheter shaft 110. Balloon 104 may include a balloon proximal end 104P and a balloon distal end 104D. The catheter shaft 110 may extend from a proximal portion 114 of the catheter system 100 to a distal portion 116 of the catheter system 100. The catheter shaft 110 may include a longitudinal axis 144. The catheter shaft 110 may also include a guidewire lumen 118, the guidewire lumen 118 being configured to move over the guidewire 112. As used herein, the guidewire lumen 118 defines a conduit through which the guidewire 112 extends. The catheter shaft 110 may also include an expansion lumen (not shown) and/or various other lumens for various other purposes. In some embodiments, the catheter 102 may have a distal opening 120, and as the catheter 102 is moved and positioned at or near the treatment site 106, the catheter 102 may receive the guidewire 112 and be tracked using the guidewire 112. In some embodiments, the balloon proximal end 104P may be coupled to the catheter shaft 110, while the balloon distal end 104D may be coupled to the guidewire lumen 118.

Balloon 104 includes a balloon wall 130 defining a balloon interior 146. Balloon 104 may be selectively inflated with balloon fluid 132 to expand from a collapsed state (as shown in fig. 1) adapted to advance catheter 102 through the vasculature of the patient to an inflated state adapted to anchor catheter 102 in position relative to treatment site 106. Stated another way, when the balloon 104 is in the inflated state, the balloon wall 130 of the balloon 104 is configured to be positioned substantially adjacent to the treatment site 106. It should be appreciated that while fig. 1 shows the balloon wall 130 of the balloon 104 as being spaced apart from the treatment site 106 of the vessel 108 when in the expanded state, this is merely for ease of illustration. It should be appreciated that when the balloon 104 is in the inflated state, the balloon wall 130 of the balloon 104 is generally substantially immediately adjacent and/or abutting the treatment site 106.

Balloons 104 suitable for use in catheter system 100 include those that can pass through the vasculature of patient 109 when in a contracted state. In some embodiments, balloon 104 is made of silicone. In other embodiments, balloon 104 may be made of Polydimethylsiloxane (PDMS), polyurethane, a polymer such as PEBAX ^TM material, nylon, or any other suitable material.

Balloon 104 may have any suitable diameter (in the expanded state). In various embodiments, balloon 104 may have a diameter (in the expanded state) ranging from less than 1 millimeter (mm) up to 25 mm. In some embodiments, balloon 104 may have a diameter (in the expanded state) ranging from at least 1.5mm up to 14 mm. In some embodiments, balloon 104 may have a diameter (in the expanded state) ranging from at least 2mm up to 5mm.

In some embodiments, balloon 104 may have a length ranging from at least 3mm to 300 mm. More specifically, in some embodiments, balloon 104 may have a length ranging from at least 8mm to 200 mm. It is to be appreciated that a balloon 104 having a relatively longer length may be positioned adjacent to a larger treatment site 106 and, thus, may be used to apply pressure waves to a larger vascular lesion 106A or multiple vascular lesions 106A and induce a fracture at a precise location within the treatment site 106. It is also understood that a longer balloon 104 may also be positioned adjacent to multiple treatment sites 106 at any given time.

Balloon 104 may be inflated to an inflation pressure of between about 1 atmosphere (atm) and 70 atm. In some embodiments, balloon 104 may be inflated to an inflation pressure of at least 20atm to 60 atm. In other embodiments, the balloon 104 may be inflated to an inflation pressure of at least 6atm to 20 atm. In still other embodiments, the balloon 104 may be inflated to an inflation pressure of at least 3atm to 20 atm. In still other embodiments, the balloon 104 may be inflated to an inflation pressure of at least 2atm to 10 atm.

Balloon 104 may have various shapes including, but not limited to, a conical shape, a square shape, a rectangular shape, a spherical shape, a conical/square shape, a conical/spherical shape, an expanded spherical shape, an elliptical shape, a conical shape, a bone shape, a stepped diameter shape (STEPPED DIAMETER SHAPE), an offset shape, or a conical offset shape. In some embodiments, balloon 104 may include a drug eluting coating or a drug eluting stent structure. The drug eluting coating or drug eluting stent may include one or more therapeutic agents including anti-inflammatory agents, anti-tumor agents, anti-angiogenic agents, and the like.

Balloon fluid 132 may be a liquid or a gas. Some examples of balloon fluids 132 suitable for use may include, but are not limited to, one or more of water, saline, contrast media (contrast media), fluorocarbon, perfluorocarbon, gas such as carbon dioxide, or any other suitable balloon fluid 132. In some embodiments, balloon fluid 132 may be used as a base inflation fluid. In some embodiments, balloon fluid 132 may include a mixture of saline and contrast media in a volume ratio of about 50:50. In other embodiments, balloon fluid 132 may include a mixture of saline and contrast media in a volume ratio of about 25:75. In still other embodiments, balloon fluid 132 may comprise a mixture of saline and contrast media in a volume ratio of about 75:25. However, it is understood that any suitable ratio of saline to contrast medium may be used. The balloon fluid 132 may be adjusted based on composition, viscosity, etc., such that the propagation rate of the pressure wave is properly manipulated. In certain embodiments, balloon fluid 132 suitable for use herein is biocompatible. The volume of the balloon fluid 132 may be adjusted by the selected light source 124 and the type of balloon fluid 132 used.

In some embodiments, contrast agents (contrast agents) used in the contrast medium may include, but are not limited to, iodine-based contrast agents, such as ionic iodine-based contrast agents or nonionic iodine-based contrast agents. Some non-limiting examples of ionic iodine-based contrast agents include diatrizoate (diatrizoate), mediatrizoic acid (metrizoate), iophthalic acid (iothalamate), and iodic acid (ioxaglate). Some non-limiting examples of non-ionic iodinated contrast agents include iopamidol (iopamidol), iohexol (iohexol), ioxilan (ioxilan), iopromide (iopromide), iodixanol (iodixanol), and ioversol (ioversol). In other embodiments, non-iodine based contrast agents may be used. Suitable non-iodine containing contrast agents may include gadolinium (III) based contrast agents (gadolinium (III) -based contrast agent). Suitable fluorocarbon agents and perfluorocarbon agents may include, but are not limited to, formulations such as perfluorocarbon dodecafluoropentane (perfluorocarbon dodecafluoropentane (DDFP, C5F 12)).

Balloon fluid 132 may include those that include an absorber that may selectively absorb light in the ultraviolet region (e.g., at least 10 nanometers (nm) to 400 nm), visible region (e.g., at least 400nm to 780 nm), or near infrared region (e.g., at least 780nm to 2.5 μm) of the electromagnetic spectrum. Suitable absorbers may include those having a maximum absorption in the spectrum from at least 10nm to 2.5 μm. Alternatively, balloon fluid 132 may include an absorber that may selectively absorb light in the mid-infrared region (e.g., at least 2.5 μm to 15 μm) or the far-infrared region (e.g., at least 15 μm to 1 mm) of the electromagnetic spectrum. In various embodiments, the absorbers may be those having an absorption maximum that matches the emission maximum of the laser used in catheter system 100. As non-limiting examples, the various lasers described herein may include neodymium: yttrium aluminum garnet (Nd: YAG-emission maximum=1064 nm) lasers, holmium: YAG (Ho: YAG-emission maximum=2.1 μm) lasers, or erbium: YAG (Er: YAG-emission maximum=2.94 μm) lasers. In some embodiments, the absorbent may be water soluble. In other embodiments, the absorbent is not water soluble. In some embodiments, the absorber used in balloon fluid 132 may be tuned to match the peak emission of light source 124. The various light sources 124 discussed elsewhere herein have emission wavelengths of at least ten nanometers to one millimeter.

The catheter shaft 110 of the catheter 102 may be coupled to one or more light guides 122A of the light guide bundle 122 in optical communication with a light source 124. Light guide 122A may be disposed along catheter shaft 110 and within balloon 104. Each light guide 122A may have a guide distal end 122D in any suitable longitudinal position relative to the length of the balloon 104. In some embodiments, each light guide 122A may be an optical fiber and the light source 124 may be a laser. The light source 124 may be in optical communication with the light guide 122A at the proximal portion 114 of the catheter system 100. More particularly, due to the presence and operation of the handle assembly 128, the light sources 124 may be in optical communication with each of the light guides 122A selectively, simultaneously, sequentially, and/or in any desired combination, order, and/or pattern.

In some embodiments, the catheter shaft 110 may be coupled to a plurality of light guides 122A, e.g., a first light guide, a second light guide, a third light guide, etc., which may be disposed at any suitable location about the guidewire lumen 118 and/or the catheter shaft 110. For example, in certain non-exclusive embodiments, two light guides 122A may be spaced approximately 180 degrees apart around the circumference of the guidewire lumen 118 and/or catheter shaft 110; the three light guides 122A may be spaced about 120 degrees around the circumference of the guidewire lumen 118 and/or the catheter shaft 110, or the four light guides 122A may be spaced about 90 degrees around the circumference of the guidewire lumen 118 and/or the catheter shaft 110. Still alternatively, the plurality of light guides 122A need not be uniformly spaced from one another about the circumference of the guidewire lumen 118 and/or the catheter shaft 110. More particularly, the light guides 122A can be uniformly or non-uniformly disposed about the guidewire lumen 118 and/or the catheter shaft 110 to achieve a desired effect at a desired location.

Catheter system 100 and/or light guide bundle 122 may include any number of light guides 122A, light guides 122A in optical communication with light source 124 at proximal portion 114 and balloon fluid 132 within balloon interior 146 of balloon 104 at distal portion 116. For example, in some embodiments, catheter system 100 and/or light guide bundle 122 may include one light guide 122A to five light guides 122A. In other embodiments, catheter system 100 and/or light guide bundle 122 may include five light guides 122A to fifteen light guides 122A. In still other embodiments, catheter system 100 and/or light guide bundle 122 may include ten light guides 122A to thirty light guides 122A. Alternatively, in still other embodiments, catheter system 100 and/or light guide bundle 122 may include greater than 30 light guides 122A.

The light guide 122A may have any suitable design for generating a plasma and/or pressure waves in the balloon fluid 132 within the balloon interior 146. In some embodiments, the light guide 122A may comprise an optical fiber or a flexible light pipe. The light guide 122A may be thin and flexible and may allow the optical signal to be transmitted with very little loss of intensity. The light guide 122A may include a core surrounded by a cladding around its circumference. In some embodiments, the core may be a cylindrical core or a partially cylindrical core. The core and cladding of light guide 122A may be formed of one or more materials including, but not limited to, one or more types of glass, silica, or one or more polymers. The light guide 122A may also include a protective coating, such as a polymer. It will be appreciated that the refractive index of the core will be greater than the refractive index of the cladding.

Each light guide 122A may direct light energy along its length from a guide proximal end 122P to a guide distal end 122D, the guide distal end 122D having at least one optical window (not shown) positioned within the balloon interior 146.

In various embodiments, the distal guide end 122D may further include and/or incorporate a distal light receiver 122R that allows light energy to move from the distal guide end 122D back through the light guide 122A to the proximal guide end 122P. In other words, the light energy may move along the light guide 122A in a first direction 121F, which first direction 121F is generally from the guide proximal end 122P of the light guide 122A toward the guide distal end 122D of the light guide 122A. At least a portion of the light energy may also move along the light guide 122A in a second direction 121S that is substantially opposite the first direction 121F, i.e., from the guide distal end 122D of the light guide 122A toward the guide proximal end 122P of the light guide 122A. Further, as described in greater detail below, after moving back through the light guide 122A (in the second direction 121S), the light energy emitted from the guide proximal end 122P may be separated and then optically detected, interrogated, and/or analyzed using the optical analyzer assembly 142.

The light guide 122A may take many configurations around and/or relative to the catheter shaft 110 of the catheter 102. In some embodiments, the light guide 122A may extend parallel to the longitudinal axis 144 of the catheter shaft 110. In some embodiments, the light guide 122A may be physically coupled to the catheter shaft 110. In other embodiments, the light guide 122A may be disposed along the length of the outer diameter of the catheter shaft 110. In still other embodiments, the light guide 122A may be disposed within one or more light guide cavities within the catheter shaft 110.

The light guides 122A can also be disposed at any suitable location about the circumference of the guidewire lumen 118 and/or catheter shaft 110, and the guide distal end 122D of each light guide 122A can be disposed at any suitable longitudinal location relative to the length of the balloon 104 and/or relative to the length of the guidewire lumen 118 to more effectively and accurately apply pressure waves for disrupting the vascular lesion 106A at the treatment site 106.

In some embodiments, light guide 122A may include one or more photoacoustic transducers 154, where each photoacoustic transducer 154 may be in optical communication with light guide 122A (in which photoacoustic transducer 154 is disposed). In some embodiments, photoacoustic transducer 154 may be in optical communication with a distal end 122D of light guide 122A. Additionally, in such embodiments, photoacoustic transducer 154 may have a shape that corresponds to and/or conforms to the distal end 122D of light guide 122A.

Photoacoustic transducer 154 is configured to convert light energy into acoustic waves at or near the distal end 122D of light guide 122A. The direction of the acoustic wave can be adjusted by changing the angle of the director distal end 122D of the light director 122A.

In some embodiments, photoacoustic transducer 154 disposed at the distal end 122D of light guide 122A may take the same shape as the distal end 122D of light guide 122A. For example, in certain non-exclusive embodiments, photoacoustic transducer 154 and/or introducer distal end 122D may have a conical shape, a convex shape, a concave shape, a bulbous shape, a square shape, a stepped shape, a semi-circular shape, an oval shape, and the like. The light guide 122A may also include additional photoacoustic transducers 154 disposed along one or more side surfaces of the length of the light guide 122A.

In some embodiments, the light guide 122A may also include one or more turning features or "diverters" (not shown in fig. 1) within the light guide 122A that are configured to direct light toward a side surface that may be located at or near the guide distal end 122D of the light guide 122A and toward the balloon wall 130 to exit the light guide 122A. The turning features may include any system feature that turns the light energy from the light guide 122A away from its axial path to face a side surface of the light guide 122A. Additionally, the light guides 122A may each include one or more light windows disposed along a longitudinal or circumferential surface of each light guide 122A and in optical communication with the turning features. Stated another way, the turning features may be configured to direct light energy in the light guide 122A toward a side surface at or near the guide distal end 122D, where the side surface is in optical communication with the light window. The light window may include portions of the light guide 122A that allow light energy to exit the light guide 122A from within the light guide 122A (e.g., portions of the light guide 122A that lack cladding material on or around the light guide 122A).

Examples of suitable turning features for use include reflective elements, refractive elements, and fiber diffusers. Turning features suitable for focusing light energy into an end (tip) distal to the light guide 122A may include, but are not limited to, those having a convex surface, a gradient index (GRIN) lens, and a mirror focusing lens. Upon contact with the turning features, the light energy is turned within the light guide 122A to one or more of the plasmon generator 133 and the photoacoustic transducer 154 in optical communication with the side surface of the light guide 122A. As described, photoacoustic transducer 154 then converts the light energy into an acoustic wave that extends away from the side surface of light guide 122A.

The source manifold 136 may be positioned at or near the proximal portion 114 of the catheter system 100. The source manifold 136 may include one or more proximal openings that may receive one or more light guides 122A of the light guide bundle 122, the guide wire 112, and/or an expansion conduit 140 coupled in fluid communication with a fluid pump 138. Catheter system 100 may also include a fluid pump 138, fluid pump 138 configured to inflate balloon 104 with balloon fluid 132 as desired.

As described above, in the embodiment shown in fig. 1, multiplexer 123 includes one or more of a light source 124, a power supply 125, a system controller 126, and a GUI 127. Alternatively, multiplexer 123 may include more or fewer components than those specifically shown in fig. 1. For example, in some non-exclusive alternative embodiments, multiplexer 123 may be designed without GUI 127. Still alternatively, one or more of the light source 124, the power source 125, the system controller 126, and the GUI 127 may be disposed within the catheter system 100 without specifically requiring the multiplexer 123.

In some embodiments, multiplexer 123 may comprise a two-channel splitter design. The director bundles 122 may include manual positioning mechanisms mounted on the optical test plate (optical breadboard) and/or the platen. This design achieves linear position adjustment and array tilting by rotating the light guide 122A axis (not shown in fig. 1) about the channel one. In other embodiments, the conditioning method may include at least two conditioning steps: 1) Aligning the planar position of the guiding beam 124B at channel 1, and 2) adjusting the light guide beam 122 to achieve optimal alignment at channel 10.

As shown in fig. 1, in some embodiments, at least a portion of the optical analyzer component 142 can be positioned within the multiplexer 123. Alternatively, the various components of the optical analyzer assembly 142 or the entire optical analyzer assembly 142 may be positioned external to the multiplexer 123 or spaced apart from the multiplexer 123.

As shown, multiplexer 123 and the components it includes are operably coupled to catheter 102, light guide beam 122, and the remainder of catheter system 100. For example, in some embodiments, as shown in fig. 1, multiplexer 123 may include a console connection aperture 148 (also sometimes referred to generally as a "socket") through which light guide beam 122 is mechanically coupled to multiplexer 123. In such embodiments, the light guide bundles 122 may include a guide coupling housing 150 (also sometimes referred to generally as a "hoop structure"), which guide coupling housing 150 houses a portion of each light guide 122A (e.g., guide proximal end 122P). The director coupling housing 150 is configured to mate and selectively remain within the console connection aperture 148 to provide a mechanical coupling between the light director bundles 122 and the multiplexer 123.

The light guide bundle 122 may also include a guide bundler (guide bundler) 152 (or "shell"), the guide bundler 152 bringing each of the individual light guides 122A closer together so that the light guides 122A and/or the light guide bundle 122 may be in a more compact form when the light guides 122A and/or the light guide bundles 122 extend into the blood vessel 108 with the catheter 102 during use of the catheter system 100. In some embodiments, the light guides 122A leading to the plasma generator 133 may be organized into light guide bundles 122, the light guide bundles 122 comprising linear blocks with a precision array of holes forming a multichannel collar structure. In other embodiments, the light guide bundles 122 may include an array of mechanical connectors or block connectors that organize the single ferrule structure into one of (i) a linear array (ii) a circular pattern and (iii) a hexagonal pattern.

Light source 124 may be selectively and/or alternatively coupled in optical communication with each light guide 122A, i.e., coupled to a guide proximal end 122P of each light guide 122A in light guide bundle 122. In particular, light source 124 is configured to generate light energy in the form of a source beam 124A (e.g., a pulsed source beam), which source beam 124A may be selectively and/or alternatively directed to each of light directors 122A in light director beam 122 as a separate directed beam 124B and received by each of light directors 122A in light director beam 122. The optical element 147 may selectively and/or alternatively direct the guided light beam 124B toward the light guide 122A and/or the multiplexer 123 in the light guide beam 122. The optical element 147 may include a lens, a focusing lens, a coupling lens, and/or a reflector. Alternatively, catheter system 100 may include more than one light source 124. For example, in one non-exclusive alternative embodiment, the catheter system 100 may include a separate light source 124 for each light guide 122A in the light guide bundle 122. The light source 124 may operate at low energy.

The light source 124 may be of any suitable design. In some embodiments, the light source 124 may be configured to provide sub-millisecond pulses of light energy from the light source 124 that are focused onto a small spot of light to couple the light energy into the guide proximal end 122P of the light guide 122A. Such pulses of light energy are then directed (direct) along the light guide 122A and/or to a location within the balloon interior 146 of the balloon 104, thereby inducing plasma formation (sometimes referred to herein as "plasma flash (PLASMA FLASH)") in the balloon fluid 132 within the balloon interior 146 of the balloon 104, such as by the plasma generator 133 that may be located at the guide distal end 122D of the light guide 122A. In particular, light emitted at the distal end 122D of the light guide 122A excites the plasma generator 133 to form a plasma within the balloon fluid 132 within the balloon interior 146. The plasma formation causes rapid bubble formation and applies a pressure wave at the treatment site 106. An exemplary plasma-induced bubble 134 is shown in fig. 1.

When a plasma is initially formed in balloon fluid 132 within balloon interior 146, it emits a broad spectrum of electromagnetic radiation. This can be seen as a visible flash of broad spectrum light. A portion of the light emitted from the plasma bubble 134 may be transmitted into the distal light receiver 122R at the director distal end 122D of the light director 122A and back to the director proximal end 122P, where it may be separated, detected, and analyzed by use of the optical analyzer assembly 142. The intensity and timing (timing) of the visible light pulses relative to the pulses that generate the plasma provide an indication of the functioning of the plasma generator 133, its energy output, and its functional condition. If the light guide 122A is damaged or broken, a visible light flash may occur at other locations of the light guide 122A. Such other visible light flashes will also be coupled into light guide 122A and brought back to light guide proximal end 122P. The intensity and timing of these other light pulses provides an indication of damage or failure of the light guide 122A or plasma generator 133. In these cases, the optical analyzer assembly 142 may include a safety shut-off system that may be selectively activated to shut off operation of the catheter system 100.

In certain embodiments, the configuration of plasma generator 133 and/or distal light receiver 122R may further allow ambient light originating from outside of catheter 102 to be coupled into the guide distal end 122D of light guide 122A. In one embodiment, optical analyzer assembly 142 monitors the returned ambient light energy passing through light guide 122A from guide distal end 122D to guide proximal end 122P. If any ambient light energy is present and in this case detected by the optical analyzer assembly 142, this is an indication that the catheter 102 is located outside the body 107 of the patient 109, and the optical analyzer assembly 142 may be configured to block the light source 124 accordingly. In particular, in this case, the safety shut-off system 283 of the optical analyzer assembly 142 may be selectively activated to shut off operation of the catheter system 100.

In various non-exclusive alternative embodiments, sub-millisecond pulses of light energy from the light source 124 may be delivered to the treatment site 106 at a frequency between about 1 hertz (Hz) and 5000Hz, between about 30Hz and 1000Hz, between about 10Hz and 100Hz, or between about 1Hz and 30 Hz. Alternatively, sub-millisecond pulses of optical energy may be delivered to the treatment site 106 at a frequency that may be greater than 5000Hz or less than 1Hz, or any other suitable frequency range.

It should be appreciated that although the light source 124 is typically utilized to provide pulses of light energy, the light source 124 may nevertheless be described as providing a single source beam 124A, i.e., a single pulsed source beam.

Light source 124 suitable for use may include various types of light sources including lasers, seed sources, and lamps. For example, in certain non-exclusive embodiments, the light source 124 may be an infrared laser that emits light energy in the form of infrared light pulses. Alternatively, as described above, light source 124 may include any suitable type of energy source as described herein.

Suitable lasers may include short pulse lasers on a sub-millisecond timescale. In some embodiments, the light source 124 may include a laser on a nanosecond (ns) timescale. Lasers may also include short pulse lasers on picosecond (ps), femtosecond (fs) and microsecond (us) timescales. It should be appreciated that there are many combinations of laser wavelength, pulse width and energy levels that can be used to achieve a plasma in the balloon fluid 132 of the catheter 102. In various non-exclusive alternative embodiments, the pulse widths may include those falling within a range including at least 10ns to 3000ns, at least 20ns to 100ns, or at least 1ns to 500 ns. Alternatively, any other suitable pulse width range may be used.

Exemplary nanosecond lasers may include those that span wavelengths of about 10 nanometers (nm) to 1 millimeter (mm) within the UV to IR spectrum. In some embodiments, light sources 124 suitable for use in catheter system 100 may include light sources capable of generating light having wavelengths from at least 750nm to 2000 nm. In other embodiments, the light source 124 may include a light source capable of generating light having a wavelength from at least 700nm to 3000 nm. In still other embodiments, the light source 124 may comprise a light source capable of generating light having a wavelength from at least 100nm to 10 micrometers (μm). Nanosecond lasers may include those with repetition rates up to 200 kHz. In some embodiments, the laser may comprise a tuned Q thulium to yttrium aluminum garnet (Tm: YAG) laser. In other embodiments, the lasers may include neodymium: yttrium aluminum garnet (Nd: YAG) lasers, holmium: yttrium aluminum garnet (Ho: YAG) lasers, erbium: yttrium aluminum garnet (Er: YAG) lasers, excimer lasers, helium neon lasers, carbon dioxide lasers, and doped lasers, pulsed lasers, fiber lasers. In still other embodiments, the light source 124 can include a SLED having a bandwidth in the range of 13.25GHz to 18.25GHz at 1064 nm.

The catheter system 100 may generate pressure waves having a maximum pressure in the range of at least 1 megapascal (MPa) to 100 MPa. The maximum pressure generated by a particular catheter system 100 will depend on the light source 124, the absorbent material, the gas bubble inflation, the propagation medium, the balloon material, and other factors. In various non-exclusive alternative embodiments, the catheter system 100 may generate pressure waves having a maximum pressure in the range of at least about 2MPa to 50MPa, at least about 2MPa to 30MPa, or at least about 15MPa to 25 MPa.

When the catheter 102 is placed at the treatment site 106, pressure waves may be applied to the treatment site 106 at a distance ranging from at least about 0.1 millimeters (mm) to greater than about 25mm extending radially from the light guide 122A. In various non-exclusive alternative embodiments, when the catheter 102 is placed at the treatment site 106, pressure waves may be applied to the treatment site 106 at a distance ranging from at least about 10mm to 20mm, at least about 1mm to 10mm, at least about 1.5mm to 4mm, or at least about 0.1mm to 10mm, extending radially from the light guide 122A. In other embodiments, pressure waves may be applied to the treatment site 106 from other suitable distances than the foregoing ranges. In some embodiments, pressure waves in the range of from at least about 2MPa to 30MPa may be applied to the treatment site 106 at a distance of from at least about 0.1mm to 10 mm. In some embodiments, pressure waves in the range of from at least about 2MPa to 25MPa may be applied to the treatment site 106 at a distance of from at least about 0.1mm to 10 mm. Still alternatively, other suitable pressure ranges and distances may be used.

The power supply 125 is electrically coupled to each of the light source 124, the system controller 126, the GUI 127, the handle assembly 128, and the optical analyzer assembly 142, and is configured to provide the necessary power to each of the light source 124, the system controller 126, the GUI 127, the handle assembly 128, and the optical analyzer assembly 142. The power supply 125 may be of any suitable design for such a purpose.

The system controller 126 is electrically coupled to the power supply 125 and receives power from the power supply 125. Additionally, a system controller 126 is coupled to each of the light source 124, the GUI 127, and the optical analyzer component 142 and is configured to control the operation of each of the light source 124, the GUI 127, and the optical analyzer component 142. The system controller 126 may include one or more processors or circuitry for controlling the operation of at least the light source 124, the GUI 127, and the optical analyzer component 142. For example, the system controller 126 may control the light source 124 to generate pulses of light energy as needed and/or at any desired excitation rate. Additionally, the system controller 126 can control the optical analyzer assembly 142 and/or operate in conjunction with the optical analyzer assembly 142 to effectively provide continuous real-time monitoring of the performance, reliability, safety, and proper use of the catheter system 100.

The system controller 126 may also be configured to control the operation of other components of the catheter system 100, such as positioning the catheter 102 adjacent the treatment site 106, expanding the balloon 104 with the balloon fluid 132, and the like. In addition, or in the alternative, the catheter system 100 may include one or more additional controllers that may be positioned in any suitable manner for controlling various operations of the catheter system 100. For example, in certain embodiments, additional controllers, and/or portions of the system controller 126 may be located and/or contained within the handle assembly 128.

GUI 127 may be accessible to a user or operator of catheter system 100. Additionally, GUI 127 is electrically connected to system controller 126. With such a design, a user or operator may use the GUI 127 to ensure that the catheter system 100 is effectively utilized to apply pressure to the treatment site 106 and induce a fracture at the treatment site 106. GUI 127 may provide information to a user or operator that may be used before, during, and after use of catheter system 100. In one embodiment, GUI 127 may provide static visual data and/or information to a user or operator. Additionally, or in the alternative, during use of catheter system 100, GUI 127 may provide dynamic visual data and/or information, such as video data or any other data that varies over time, to a user or operator. In various embodiments, GUI 127 may include one or more colors, different sizes, varying brightness, etc., that may alert a user or operator. Additionally, or in the alternative, GUI 127 may provide audio data or information to a user or operator. The details of GUI 127 may vary depending on the design requirements of catheter system 100 or the particular needs, specifications, and/or desires of the user or operator.

As shown in fig. 1, the handle assembly 128 may be positioned at or near the proximal portion 114 of the catheter system 100 and/or near the source manifold 136. In this embodiment, handle assembly 128 is coupled to balloon 104 and is positioned spaced apart from balloon 104. Alternatively, the handle assembly 128 may be positioned at another suitable location.

The handle assembly 128 is manipulated and used by a user or operator to operate, position and control the catheter 102. The design and specific features of the handle assembly 128 may be varied to suit the design requirements of the catheter system 100. In the embodiment shown in fig. 1, handle assembly 128 is separate from, but in electrical and/or fluid communication with, one or more of system controller 126, light source 124, fluid pump 138, GUI 127, and optical analyzer assembly 142. In some embodiments, the handle assembly 128 may be integrated within the handle assembly 128 and/or include at least a portion of the system controller 126. For example, as shown, in some such embodiments, the handle assembly 128 may include circuitry (not shown in fig. 1) that may form at least a portion of the system controller 126. In some embodiments, the circuitry may receive electrical signals or data from the optical analyzer component 142. In addition, or in the alternative, the circuitry may transmit such electrical signals or otherwise provide data to the system controller 126.

In one embodiment, the circuitry may include a printed circuit board (not shown) having one or more integrated circuits, or any other suitable circuitry. In alternative embodiments, the circuitry may be omitted or may be included within the system controller 126, and in various embodiments, the system controller 126 may be located external to the handle assembly 128 (e.g., within the multiplexer 123). It is to be understood that handle assembly 128 may include fewer or more components than are specifically shown and described herein.

As with all of the embodiments shown and described herein, various structures may be omitted from the figures for clarity and ease of understanding. Further, the drawings may include certain structures that may be omitted without departing from the intent and scope of the invention.

Fig. 2 is a simplified schematic diagram of another embodiment of a portion of a catheter system 200. Fig. 2 shows a non-limiting, non-exclusive example of a Master Oscillator and Power Amplifier (MOPA) configuration for light source 224. In some such embodiments, the MOPA configuration enables the low power master oscillator to seed the power amplifier with the appropriate pulses for amplification. If the pulse energy is low enough that the amplifier gain is not significantly depleted during the pulse, the temporal shape of the output of the system will closely match the output of the seed laser.

The MOPA configuration also enables a significant increase in linewidth of the light source 224 while minimizing nonlinear optical processes and maintaining adequate light energy transmission through the light guide 222A. This configuration provides a technique and method for significantly increasing the linewidth of the energy output by the light source 224 by enabling transmission through the small diameter light guide 222A with minimal loss.

As shown in fig. 2, catheter system 200 may include light guide 222A, light source 224, power supply 225, plasma generator 233, and optical element 247. These components may be substantially similar in form, placement, and/or function to the components previously described with respect to catheter system 100 shown in fig. 1. The catheter system 200 may also include a seed controller 258, a seed source 260, a pre-amplifier 262, and an amplifier 264.

Seed controller 258 controls the operation and/or function of seed source 260. For example, the seed controller 258 may control the output of energy from the seed source 260. Seed controller 258 may control the wavelength, center wavelength, seed pulse shape, frequency, and/or any suitable characteristic of the energy output by seed source 260. Seed controller 258 may directly modulate seed source 260. The design and specific features of seed controller 258 may be varied to suit the design requirements of catheter system 200 and/or seed source 260.

Seed controller 258 may include one or more processors, microprocessors, and/or circuitry for controlling at least the operation of seed source 260. Seed controller 258 may include a printed circuit board with one or more integrated circuits, an acousto-optic modulator, or any other suitable circuit. In alternative embodiments, seed controller 258 may be omitted or may be included within system controller 126 (as shown in fig. 1), and in various embodiments, system controller 126 may be located external to light source 124, for example, within multiplexer 123. It is to be understood that seed controller 258 may include fewer or more components than are specifically shown and described herein.

The seed source 260 outputs light energy. Seed source 260 may be in optical communication with light guide 222A, optical element 247, pre-amplifier 262, and amplifier 264. Seed source 260 may be free-space coupled with a pre-amplifier 262 and an amplifier 264 within light source 224. The seed source 260 may be configured with a seed shift of the center wavelength that is above and below the amplifier wavelength of the amplifier 264. The seed source 260 may be configured to have a seed pulse shape that is controlled at least in part by (i) directly modulating the seed source 260, or (ii) by an acousto-optic modulator (which may be included within the seed controller 258).

The seed source 260 may have a seed linewidth inherent to the seed source. The seed source 260 may be programmable such that the seed linewidth is adjustable to suit the design requirements of the catheter system 200 and/or the seed source 260. In various embodiments, the seed source 260 may be operated at a low threshold to extend the seed pulse shape. The seed linewidth of the seed source 260 may be adjusted such that the seed center wavelength and seed bus width substantially match the preamplifier center wavelength of the preamplifier 262 and/or the amplifier center wavelength of the amplifier 264. By substantially matching the linewidth and/or the center wavelength, the energy conversion of the light energy is improved.

The design and specific characteristics of seed source 260 may be varied to accommodate the design requirements of catheter system 200, light source 224, light guide 222A, optical element 247, preamplifier 262 and/or amplifier 264. Seed source 260 may include a diode, a superluminescent diode, a diode laser, a programmable semiconductor laser, a gated fiber laser, a low power solid state laser, and/or a modulated distributed feedback laser. It is to be understood that seed source 260 may include fewer or more components than are specifically shown and described herein.

The pre-amplifier 262 receives and amplifies the light energy from the seed source 260. In various embodiments, the pre-amplifier 262 may be in optical communication with the light guide 222A, the optical element 247, the seed source 260, and/or the amplifier 264. The pre-amplifier 262 may be powered by a power supply 225. The design and specific features of the pre-amplifier 262 may be varied to accommodate the design requirements of the catheter system 200, the light source 224, the light guide 222A, the optical element 247, the seed source 260, and/or the amplifier 264.

The pre-amplifier 262 may include a fiber laser, a solid state laser, a flash lamp, and/or a diode pumped neodymium-doped yttrium aluminum garnet rod. It is to be understood that the preamplifier 262 may include fewer or more components than are specifically shown and described herein. In some embodiments, the pre-amplifier 262 may be omitted entirely from the light source 224, depending on the output energy of the seed source 260 and the design requirements of the catheter system 200, the light source 224, the light guide 222A, the optical element 247, and/or the amplifier 264. In other embodiments, the light source 224 may include a plurality of preamplifiers 262.

The amplifier 264 receives and amplifies the light energy from the seed source 260 and/or the preamplifier 262. In various embodiments, the amplifier 264 may be in optical communication with the light guide 222A, the optical element 247, the seed source 260, and/or the pre-amplifier 262. The amplifier 264 may be powered by a power supply 225. The design and specific features of amplifier 264 may be varied to accommodate the design requirements of catheter system 200, light source 224, light guide 222A, optical element 247, seed source 260, and/or pre-amplifier 262.

Amplifier 264 may include a fiber laser, a diode pumped solid state laser, a gain medium, a high gain stage configured to have high energy output capability, and/or a flash lamp. The gain medium may comprise (i) neodymium-doped yttrium aluminum garnet rods, (ii) neodymium-doped yttrium aluminum garnet slabs, (iii) neodymium-doped glass, and/or (iv) erbium-doped yttrium lithium fluoride. The gain medium may be optically coupled to one of the laser diode stack and the flash lamp (e.g., within the amplifier 264). It is to be understood that the amplifier 264 may include fewer or additional components than those specifically shown and described herein. The amplifier 264 may have a varying amplifier bandwidth. In some embodiments, the amplifier bandwidth may vary from 1MHz to 1000GHz. In other embodiments, the amplifier bandwidth may be less than 1MHz or greater than 1000GHz.

The amplifier 264 may comprise a solid state high power amplifier omitting the tuning cavity. The solid state high power amplifier may be driven to amplify the optical energy to the gain medium linewidth of the gain medium. In some embodiments, when the gain medium comprises neodymium doped yttrium aluminum garnet, the gain medium linewidth is about 0.7nm. In other embodiments, the optical energy solid state high power amplifier may be driven to amplify optical energy to a gain medium linewidth greater than 0.7nm or less than 0.7nm.

In some embodiments, the amplifier 264 may be omitted entirely from the light source 224, depending on the output energy of the seed source 260 and the design requirements of the catheter system 200, the light source 224, the light guide 222A, the optical element 247, and/or the pre-amplifier 262. In other embodiments, the light source 224 may include a plurality of amplifiers 264.

Fig. 3 is a simplified schematic diagram of yet another embodiment of a portion of a catheter system 300. As shown in fig. 3, the catheter system 300 may include a light guide 322A, a light source 324, a power supply 325, a plasma generator 333, as well as an optical element 347, a seed controller 358, a seed source 360, a pre-amplifier 362, and an amplifier 364. These components may be substantially similar in form, placement, and/or function to the components previously described with respect to catheter system 300 shown in fig. 1-2. In some embodiments, the catheter system 300 may further include a plurality of coupled light guides 322C and collimators 366.

The coupling light guide 322C may optically couple various components of the light source 324. For example, as shown in fig. 3, a coupling light guide 322C may optically couple the seed source 360 to the pre-amplifier 362, and another coupling light guide 322C may optically couple the pre-amplifier 362 to the collimator 366.

The coupling modes of the various components within the light source 324 may be mixed according to (i) the design requirements of the catheter system 300 and/or the light source, and (ii) the energy outputs of the seed source 360, the pre-amplifier 362, and the amplifier 364. For example, the free-space coupling and the coupling light guide 322C may each be utilized within the light source 324 (e.g., as shown in fig. 3).

The design and specific features of the coupled light guide 322C may be varied to accommodate the design requirements of the catheter system 300, the light source 324, the light guide 322A, the optical element 347, the seed source 360, the preamplifier 362, the amplifier 364, and/or the collimator 366. The coupling light guide 322C may be a fiber optic cable.

The collimator 366 may collimate the optical energy output by the seed source 360, the pre-amplifier 362, and/or the amplifier 364. The collimator 366 may be in optical communication with the light guide 322A, the optical element 347, the seed source 360, the preamplifier 362 and/or the amplifier 364. The design and specific features of collimator 366 may be varied to accommodate the design requirements of catheter system 300, light source 324, light guide 322A, optical element 347, seed source 360, preamplifier 362 and/or amplifier 364. It is to be understood that collimator 366 may include fewer or more components than are specifically shown and described herein.

Fig. 4 is a simplified schematic diagram of yet another embodiment of a portion of a catheter system 400. As shown in fig. 4, the catheter system 400 may include a light guide 422A, a plurality of coupled light guides 422C, a light source 424, a power supply 425, a plasma generator 433, as well as an optical element 447, a seed controller 458, a seed source 460, a pre-amplifier 462, an amplifier 464, and a collimator 466. These components may be substantially similar in form, placement, and/or function to the components previously described with respect to catheter system 400 shown in fig. 1-3. In some embodiments, the catheter system 400 may further include a linewidth modifier 468.

The linewidth modifier 468 modifies the linewidth of the light energy output by the seed source 460. In various embodiments, the linewidth modifier 468 may be in optical communication with the light guide 422A, the optical element 447, the seed source 460, the pre-amplifier 462, and/or the amplifier 464. The linewidth modifier 468 and the seed source 460 may work cooperatively to (i) increase the seed linewidth of the seed source 460, (ii) improve the amplification of the light energy, and (iii) minimize Stimulated Brillouin Scattering (SBS) in the light guide 422A.

The design and specific features of the linewidth modifier 468 may be varied to suit the design requirements of the catheter system 400, the light guide 422A, the light source 424, the optical element 447, the seed source 460, the pre-amplifier 462, and/or the amplifier 464. This linewidth modifier 468 may include, by way of non-limiting, non-exclusive example, a band-limited filter and/or a fiber bragg grating. It is to be understood that the linewidth modifier 468 may include fewer or more components than are specifically shown and described herein.

Laser device

Lasers suitable for use herein may include various types of lasers, including lasers and lamps. Suitable lasers may include short pulse lasers on a sub-millisecond timescale. In some embodiments, the laser may comprise a nanosecond (ns) time scale laser. Lasers may also include short pulse lasers on picosecond (ps), femtosecond (fs) and microsecond (us) timescales. It should be appreciated that there are many combinations of laser wavelengths, pulse widths, and energy levels that may be employed to achieve a plasma in the balloon fluid of the catheter shown and/or described herein. In various embodiments, the pulse widths may include those falling within a range including from at least 10ns to 200 ns. In some embodiments, the pulse widths may include those falling within a range including from at least 20ns to 100 ns. In other embodiments, the pulse widths may include those falling within a range including from at least 1ns to 5000 ns.

Exemplary nanosecond lasers may include those that span wavelengths of about 10 nanometers to 1 millimeter in the UV to IR spectrum. In some embodiments, lasers suitable for use in the catheter systems herein may include those capable of generating light having a wavelength from at least 750nm to 2000 nm. In some embodiments, lasers may include those capable of generating light having wavelengths from at least 700nm to 3000 nm. In some embodiments, lasers may include those capable of generating light having wavelengths from at least 100nm to 10 micrometers (μm). Nanosecond lasers may include those with repetition rates up to 200 kHz. In some embodiments, the laser may comprise a tuned Q thulium to yttrium aluminum garnet (Tm: YAG) laser. In other embodiments, the lasers may include neodymium: yttrium aluminum garnet (Nd: YAG) lasers, holmium: yttrium aluminum garnet (Ho: YAG) lasers, erbium: yttrium aluminum garnet (Er: YAG) lasers, excimer lasers, helium neon lasers, carbon dioxide lasers, and doped lasers, pulsed lasers, fiber lasers.

Pressure wave

The conduits shown and/or described herein may generate pressure waves having a maximum pressure in the range of at least 1 megapascal (MPa) to 100 MPa. The maximum pressure generated by a particular catheter will depend on the laser, the absorbing material, the bubble expansion, the propagation medium, the balloon material, and other factors. These factors may include:

(i) The pulse energy may be a major factor in determining the size of the bubbles generated and their ability to rupture calcified lesions. The clinical effect is directly related to the mechanical energy, not to the acoustic shock wave preceding the mechanical bubble. The energy has an inverse cubic relationship (cubic relationship):

(ii) The effect of the pulse width and envelope (envelope) shape is small. These factors affect the overall conversion efficiency and the amplitude of the acoustic shock wave before the mechanical bubble.

(Iii) The transferred energy, more energy transferred to the region where the plasma is generated on the relaxation time scale of the phenomenon, increases the conversion efficiency, and filling more light energy into the plasma before the bubble begins to form increases the conversion efficiency and peak sound energy.

(Iv) Time stretching of the light energy pulses is an effective method of reducing the surface irradiance for the light guide material below the damage threshold while maintaining the total energy in the pulses to maximize the bubble size.

In some embodiments, the conduits shown and/or described herein may generate pressure waves having a maximum pressure in the range of at least 2MPa to 50MPa. In other embodiments, the conduits shown and/or described herein may generate pressure waves having a maximum pressure in the range of at least 2MPa to 30 MPa. In still other embodiments, the conduits shown and/or described herein may generate pressure waves having a maximum pressure in the range of at least 15MPa to 25 MPa. In some embodiments, the pressure waves that the catheters shown and/or described herein can generate have peak pressures ：1MPa、2MPa、3MPa、4MPa、5MPa、6MPa、7MPa、8MPa、9MPa、10MPa、11MPa、12MPa、13MPa、14MPa、15MPa、16MPa、17MPa、18MPa、19MPa、20MPa、21MPa、22MPa、23MPa、24MPa or 25MPa、26MPa、27MPa、28MPa、29MPa、30MPa、31MPa、32MPa、33MPa、34MPa、35MPa、36MPa、37MPa、38MPa、39MPa、40MPa、41MPa、42MPa、43MPa、44MPa、45MPa、46MPa、47MPa、48MPa、49MPa or 50MPa that are greater than or equal to the following values. It will be appreciated that the conduits shown and/or described herein may generate pressure waves having an operating pressure or maximum pressure that may fall within a range, wherein any of the foregoing amounts may be used as a lower or upper limit of the range, so long as the lower limit of the range is a value less than the upper limit of the range.

Therapeutic treatments may act via fatigue mechanisms or strength mechanisms. For the fatigue mechanism, the operating pressure will be about at least 0.5MPa to 2MPa or about 1MPa. For the strong regime, the operating pressure will be about at least 20MPa to 30MPa or about 25MPa. Pressures between the extremes of these two ranges may act on the treatment site using a combination of fatigue and strength mechanisms.

The pressure waves described herein may be applied to the treatment site from a distance in the range of at least 0.01 millimeters (mm) to 25mm extending radially from a longitudinal axis of the catheter at the treatment site. In some embodiments, the pressure wave may be applied to the treatment site from a distance in the range of at least 1mm to 20mm extending radially from the longitudinal axis of the catheter at the treatment site. In other embodiments, the pressure wave may be applied to the treatment site from a distance in the range of at least 0.1mm to 10mm extending radially from the longitudinal axis of the catheter at the treatment site. In still other embodiments, the pressure wave may be applied to the treatment site from a distance in the range of at least 1.5mm to 4mm extending radially from the longitudinal axis of the catheter at the treatment site. In some embodiments, the pressure wave may be applied to the treatment site at a distance ranging from at least 2MPa to 30MPa from 0.1mm to 10 mm. In some embodiments, the pressure wave may be applied to the treatment site at a distance ranging from at least 2MPa to 25MPa from 0.1mm to 10 mm. In some embodiments, the pressure wave may be applied to the treatment site from a distance that may be greater than or equal to 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, or 0.9mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm, or may be an amount that falls between or outside of any of the foregoing ranges.

By shaping the temporal form of the light pulse to have a fast rise time and minimal overshoot (ideally close to a square wave), the efficiency of generating the pressure wave can be increased and the amount of energy that can be delivered in a given time interval can be increased while the peak laser intensity is reduced to remain below the damage threshold of the fiber.

The present technology also relates to methods for treating a treatment site within or adjacent to a vessel wall, which methods utilize the devices disclosed herein.

It should be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content and/or context clearly dictates otherwise. It should also be noted that the term "or" is generally employed in its sense including "and/or" unless the content or context clearly dictates otherwise.

It should also be noted that, as used in this specification and the appended claims, the phrase "configured" describes a system, apparatus, or other structure that is constructed or arranged to perform a particular task or to employ a particular configuration. The phrase "configured" may be used interchangeably with other similar phrases such as disposed and configured, constructed and disposed, constructed, manufactured and disposed, and the like.

As used herein, reference to a range of numerical values by endpoints is intended to include all numbers subsumed within that range (e.g., 2 to 8 includes 2, 2.1, 2.8, 5.3, 7, 8, etc.).

It will be appreciated that the figures shown and described are not necessarily drawn to scale, and that they are provided for ease of reference and understanding and for relative positioning of the structures.

The title is used herein to keep pace with the recommendation according to 37cfr 1.77 or otherwise provide organizational cues. These headings should not be construed as limiting or characterizing the invention as set forth in any claims that may be issued by the present disclosure. As an example, a description of a technology in the "background" does not constitute an admission that the technology is prior art to any invention in this disclosure. Neither "summary" nor "abstract" is considered to be a feature of the invention described in the issued claims.

The embodiments described herein are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments were chosen and described so that others skilled in the art may recognize and understand the principles and practices. Thus, various aspects have been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope herein.

It is to be understood that while many different embodiments of catheter systems have been illustrated and described herein, one or more features of any one embodiment may be combined with one or more features of one or more of the other embodiments, so long as such combination meets the intent of the present invention.

While many exemplary aspects and embodiments of catheter systems have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope, and are not intended to be limiting to the details of construction or design shown herein.

Claims

1. A catheter system for treating a treatment site within or adjacent a vessel wall or heart valve, the catheter system comprising:

a light guide configured to selectively receive light energy;

A light source that generates the light energy, the light source in optical communication with the light guide; the light source includes: (i) a seed source outputting said light energy; (ii) A preamplifier receiving the optical energy from the seed source, the preamplifier in optical communication with the seed source; and (iii) an amplifier that receives the optical energy from the pre-amplifier, the amplifier in optical communication with the pre-amplifier and the optical director.

2. The catheter system of claim 1, further comprising a seed controller that controls the seed source.

3. The catheter system of any one of claims 1-2, further comprising an optical element configured to direct the light energy into the light guide.

4. The catheter system of any of claims 1-3, wherein the seed source comprises one of a diode laser, a programmable semiconductor laser, a gated fiber laser, and a low power solid state laser.

5. The catheter system of any of claims 1-4, wherein the seed source, the pre-amplifier, and the amplifier are free-space coupled within the light source.

6. The catheter system of any of claims 1-5, wherein the seed source is optically coupled to the pre-amplifier by a first coupling light guide and the pre-amplifier is optically coupled to the amplifier by a second coupling light guide.

7. The catheter system of any of claims 1-6, wherein the pre-amplifier comprises one of a fiber laser, a solid state laser, a flash lamp, and a diode pumped neodymium-doped yttrium aluminum garnet rod.

8. The catheter system of any of claims 1-7, wherein the amplifier comprises one of a fiber laser, a diode pumped solid state laser, a flash lamp, and a high gain stage configured to have a high energy output capability.

9. The catheter system of any of claims 1-8, wherein the amplifier comprises a gain medium comprising one of (i) a neodymium-doped yttrium aluminum garnet rod, (ii) a neodymium-doped yttrium aluminum garnet slab, (iii) a neodymium-doped glass, and (iv) an erbium-doped yttrium lithium fluoride, the gain medium being optically coupled to one of a laser diode stack and a flash lamp.

10. The catheter system of any one of claims 1-9, wherein the light source comprises a collimator that collimates light energy output by the preamplifier, the collimator being in optical communication with the preamplifier and the amplifier.

11. A catheter system for treating a treatment site within or adjacent a vessel wall or heart valve, the catheter system comprising:

a light guide configured to selectively receive light energy;

A light source that generates the light energy, the light source in optical communication with the light guide; the light source includes: (i) a seed source outputting said light energy; (ii) A line width modifier for modifying a line width of the optical energy output by the seed source; (iii) A pre-amplifier receiving the optical energy from the linewidth modifier, the pre-amplifier in optical communication with the linewidth modifier; (iv) A collimator that collimates the optical energy output by the preamplifier, the collimator in optical communication with the preamplifier; and (v) an amplifier receiving the optical energy from the pre-amplifier, the amplifier in optical communication with the collimator and the light guide.

12. The catheter system of claim 11, wherein the seed source comprises a modulated distributed feedback laser.

13. The catheter system of any of claims 11-12, wherein the seed source comprises a plurality of modulated distributed feedback lasers.

14. The catheter system of claim 13, wherein the plurality of modulated distributed feedback lasers are configured to have a seed offset at a center wavelength that is above and below an amplifier wavelength of the amplifier.

15. The catheter system of any of claims 11-14, wherein the seed source is optically coupled to the linewidth modifier by a first coupling light guide.

16. Catheter system according to any of claims 11-15, wherein the seed pulse shape of the seed source is controlled at least in part by directly modulating the seed source.

17. The catheter system of any of claims 11-16, wherein a seed pulse shape of the seed source is controlled at least in part by an acousto-optic modulator.

18. The catheter system of any one of claims 11-17, wherein the seed source comprises a diode configured to have high spatial coherence and low temporal coherence.

19. The catheter system of claim 18, wherein the diode is a superluminescent diode.

20. The catheter system of any of claims 11-19, wherein the linewidth modifier is a band-limiting filter.

21. The catheter system of any of claims 11-19, wherein the linewidth modifier is a fiber bragg grating.

22. The catheter system of any one of claims 11-21, wherein the seed source and the line width modifier work cooperatively to (i) increase a seed line width of the seed source, (ii) improve amplification of the optical energy, and (iii) minimize stimulated brillouin scattering in the light guide.

23. A catheter system for treating a treatment site within or adjacent a vessel wall or heart valve, the catheter system comprising:

a light guide configured to selectively receive light energy;

A light source that generates light energy, the light source in optical communication with the light guide; the light source includes (i) a seed source that outputs light energy, and (ii) an amplifier that receives the light energy from the seed source, the amplifier being in optical communication with the seed source and the light guide.

24. The catheter system of claim 23, further comprising a seed controller that controls the seed source.

25. The catheter system of any one of claims 23-24, further comprising an optical element configured to direct the light energy into the light guide.

26. The catheter system of any one of claims 23-25, wherein the seed source comprises one of a diode laser, a programmable semiconductor laser, a gated fiber laser, and a low power solid state laser.

27. The catheter system of any one of claims 23-26, wherein the seed source and the amplifier are free-space coupled within the light source.

28. The catheter system of any one of claims 23-27, wherein the amplifier comprises one of a fiber laser, a diode pumped solid state laser, a flash lamp, and a high gain stage configured to have a high energy output capability.

29. The catheter system of any of claims 23-28, wherein the amplifier comprises a gain medium comprising one of (i) a neodymium-doped yttrium aluminum garnet rod, (ii) a neodymium-doped yttrium aluminum garnet slab, (iii) a neodymium-doped glass, and (iv) an erbium-doped yttrium lithium fluoride, the gain medium being optically coupled to one of a laser diode stack and a flash lamp.

30. The catheter system of any one of claims 23-29, wherein the seed source comprises a modulated distributed feedback laser.

31. The catheter system of any one of claims 23-30, wherein the seed source comprises a plurality of modulated distributed feedback lasers.

32. The catheter system of claim 31, wherein the plurality of modulated distributed feedback lasers are configured to have a seed shift at a center wavelength that is above and below an amplifier wavelength of the amplifier.

33. The catheter system of any one of claims 23-32, wherein a seed pulse shape of the seed source is controlled at least in part by directly modulating the seed source.

34. The catheter system of any one of claims 23-33, wherein a seed pulse shape of the seed source is controlled at least in part by an acousto-optic modulator.

35. The catheter system of any one of claims 23-34, wherein the seed source comprises a diode configured to have high spatial coherence and low temporal coherence.

36. The catheter system of claim 35, wherein the diode is a superluminescent diode.