Creation of plasma via non-aqueous optical breakdown laser pulse energy to achieve vascular calcification disruption

Abstract

A catheter system (100) for treating a treatment site (106) within or adjacent to a blood vessel (108) includes a power source (124), a light guide (122), and a plasma target (242). In various embodiments, the light guide (122) receives power from the power source (124). The light guide (122) has a distal tip (244), and the light guide (122) emits light energy (243) in a direction away from the distal tip (244). The plasma target (242) is spaced apart from the distal tip (244) of the light guide (122) by a target gap distance (245). The plasma target (242) is configured to receive light energy (243) from the light guide (122) such that plasma bubbles (234) are generated at the plasma target (242). The power source (124) may be a laser, and the light guide (122) may be an optical fiber. The catheter system (100) may also be an inflatable balloon (104) surrounding the distal tip (244) of the light guide (122). The plasma target (242) may have a target surface (1672) that receives the light energy (243) from the light guide (122). The plasma target (242) may be formed from one or more of tungsten, tantalum, platinum, molybdenum, niobium, iridium, magnesium oxide, beryllium oxide, tungsten carbide, titanium nitride, titanium carbonitride, and titanium carbide.

Description

Background Technology

[0001] Vascular lesions within and near the body's blood vessels may be associated with an increased risk of major adverse events such as myocardial infarction, embolism, deep vein thrombosis, and stroke. Severe vascular lesions can be difficult to treat, and physicians may struggle to achieve patency in clinical settings.

[0002] Vascular lesions can be treated with interventions such as medication, balloon angioplasty, atherosclerosis resection, stent implantation, and vascular graft bypass surgery. These interventions are not always ideal, and may require follow-up treatments to resolve the lesions.

[0003] Creating plasma via optical breakdown of aqueous solutions requires a large amount of energy over an extremely short time; this energy is then converted into therapeutic bubbles and / or therapeutic pressure waves. With sufficiently high energy and sufficiently short pulse durations, the distal end of the optical guide used to deliver light energy to generate plasma may be damaged. Improving the conversion efficiency from light energy to (plasma)pressure waves and the manner of bubble growth will reduce the energy handling requirements of the optical delivery system. Therefore, equivalent treatment will require less input energy while minimizing potential damage to the optical guide.

[0004] As a method for intravascular lithotripsy catheters, the creation of plasma near the distal end of a small-diameter optical guide in cases of aqueous optical breakdown may be self-damaging due to proximity to plasma creation and / or pressure waves, high plasma temperature, and water jets from bubble collapse, etc. Summary of the Invention

[0005] This summary is a general overview of the doctrine of this application and is not intended to provide a comprehensive or exhaustive discussion of the subject matter. Further details can be 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 observing the accompanying drawings, each of which should not be considered limiting. The scope of this invention is defined by the appended claims and their legal equivalents.

[0006] This invention relates to a catheter system for treating a treatment site within or adjacent to a blood vessel. In some embodiments, the catheter system includes a power source, a light guide, and a plasma target. The light guide receives power from the power source. The light guide has a distal tip and emits light energy in a direction away from the distal tip. The plasma target is spaced apart from the distal tip of the light guide by a target gap distance. The plasma target is configured to receive light energy from the light guide such that plasma is generated at the plasma target upon receiving light energy from the light guide.

[0007] In some embodiments, the power source is a laser. In various embodiments, the light guide is an optical fiber.

[0008] In some embodiments, the catheter system may also include an inflatable balloon surrounding the distal tip of the light guide.

[0009] In various embodiments, the catheter system may also include an inflatable balloon. In some such embodiments, a plasma target may be positioned within the inflatable balloon.

[0010] In some embodiments, the target gap distance is greater than 1µm, 10µm, 100µm, 1mm, 2mm, 3mm, 5mm, and / or 1cm.

[0011] In various embodiments, the plasma target may have a substantially circular cross-sectional shape, a substantially square cross-sectional shape, a substantially rectangular cross-sectional shape, a substantially oval cross-sectional shape, a substantially pentagonal cross-sectional shape, a substantially hexagonal cross-sectional shape, a substantially octagonal cross-sectional shape, a polygonal cross-sectional shape, a parallelogram cross-sectional shape, a trapezoidal cross-sectional shape, or a substantially rhomboid cross-sectional shape.

[0012] In some embodiments, the catheter system may also include a guidewire lumen. In some such embodiments, an optical guide may be coupled to the guidewire lumen.

[0013] In some embodiments, the plasma target has a target surface that receives light energy from the photoguide. In various embodiments, the target surface has an angle that is substantially orthogonal to the direction in which the light energy is emitted to the plasma target. In various embodiments, the target surface has an angle greater than about 45 degrees and less than about 135 degrees relative to the direction in which the light energy is emitted to the plasma target. In some embodiments, the target surface may have an angle greater than zero degrees and less than 180 degrees relative to the direction in which the light energy is emitted to the plasma target.

[0014] In various embodiments, the light guide includes a distal region having a longitudinal axis. The direction of emitting light energy may be substantially along the longitudinal axis of the distal region. Alternatively, the direction of emitting light energy may be substantially perpendicular to the longitudinal axis of the distal region. More alternatively, the direction of emitting light energy may be angled relative to the longitudinal axis of the distal region. For example, in some embodiments, the direction of emitting light energy has an angle greater than zero degrees and less than 180 degrees relative to the longitudinal axis. In various embodiments, the direction of emitting light energy may have an angle greater than 45 degrees and less than 135 degrees relative to the longitudinal axis.

[0015] In some embodiments, the duct system may include a plurality of plasma targets spaced apart from the distal tip of the light guide. In some such embodiments, at least one of the plurality of plasma targets may be configured to receive light energy from the light guide.

[0016] In various embodiments, the plasma target may be formed at least in part from stainless steel and its variants, tungsten, tantalum, platinum, molybdenum, niobium and iridium.

[0017] In some embodiments, the plasma target may be formed at least in part from one of magnesium oxide, beryllium oxide, tungsten carbide, titanium nitride, titanium carbonitride, and titanium carbide.

[0018] In some embodiments, the plasma target may be formed at least in part from diamond CVD and diamond.

[0019] In various embodiments, the plasma target may be formed at least in part from transition metals, metal alloys, and / or ceramic materials.

[0020] In some embodiments, the plasma target may be fixedly coupled to the light guide. Alternatively, the plasma target may be movably coupled to the light guide. More alternatively, the plasma target may be detached from the light guide.

[0021] In some applications, the catheter system may include a guidewire lumen. In some such embodiments, a plasma target may substantially surround the guidewire lumen.

[0022] In some embodiments, the target surface may include one or more surface features, which may include one or more of notches, protrusions, and beveled edges.

[0023] In some embodiments, the target surface may have a conical shape, a pyramidal shape, a dome shape, a concave shape, a convex shape, a multifaceted shape, a coiled shape, a spring-like shape, and / or a slightly spiral shape.

[0024] In various embodiments, the plasma target can be movable relative to the light guide. In some embodiments, the plasma target can be spring-loaded.

[0025] In some embodiments, the catheter system may include a guidewire lumen, and the plasma target may be fixed to or otherwise coupled to the guidewire lumen.

[0026] In some embodiments, the conduit system may include a second light guide that receives power from a power source. The second light guide may have a second distal tip. The second light guide may emit light energy in a direction toward a plasma target away from the second distal tip. The plasma target may be spaced apart from the second distal tip of the second light guide. The plasma target may be configured to receive light energy from the second light guide such that, upon receiving light energy from the second light guide, a second plasma is generated at the plasma target.

[0027] In some embodiments, the conduit system may include a second light guide and a second plasma target. The second light guide may receive power from a power source. The second light guide may have a second distal tip. The second light guide may emit light energy in a direction away from the second distal tip toward the second plasma target. The second plasma target may be spaced apart from the plasma target and the second distal tip of the second light guide. The second plasma target may be configured to receive light energy from the second light guide such that, upon receiving light energy from the second light guide, a second plasma is generated at the second plasma target.

[0028] In various embodiments, the present invention may also relate to a method for creating plasma using laser pulse energy to optically break up vascular calcifications in blood vessels. In some embodiments, the method includes the step of providing any of the catheter systems shown and / or described herein.

[0029] In some embodiments, the plasma target may be formed at least in part from polymers, polymeric materials, and / or plastics such as polyimide and nylon. Attached Figure Description

[0030] The novel features of the invention, and the invention itself (both in relation to its structure and operation), will be best understood from the accompanying drawings in conjunction with the description, in which similar reference numerals refer to similar parts, and wherein:

[0031] Figure 1 This is a schematic cross-sectional view of a catheter system having the features of the invention according to various embodiments herein;

[0032] Figure 2 This is a simplified schematic side view of one embodiment of a catheter system, which includes a portion of a catheter.

[0033] Figure 3A This is a simplified schematic side view of one embodiment of a catheter system, including a portion of a catheter, shown in an inflated state;

[0034] Figure 3B It is indicated as being in a contracted state. Figure 3A A simplified schematic side view of this portion of the catheter shown;

[0035] Figure 4 This is a simplified schematic side view of one embodiment of a catheter system, which is another embodiment of a catheter system;

[0036] Figure 5 This is a simplified schematic side view of one embodiment of a catheter system, which is another embodiment of a catheter system;

[0037] Figure 6 This is a simplified schematic side view of one embodiment of a catheter system, which is another embodiment of a catheter system;

[0038] Figure 7A This is a simplified schematic side view of one embodiment of a catheter system, which is another embodiment of a catheter system;

[0039] Figure 7B This is a simplified schematic side view of one embodiment of a catheter system, which is another embodiment of a catheter system;

[0040] Figure 8 Is Figure 1 A schematic cross-sectional view of the conduit system taken along line 8-8 in the diagram;

[0041] Figure 9 This is a schematic cross-sectional view of another embodiment of the catheter system;

[0042] Figure 10 This is a schematic cross-sectional view of yet another embodiment of the catheter system;

[0043] Figure 11 This is a schematic cross-sectional view of yet another embodiment of the catheter system;

[0044] Figure 12 This is a schematic cross-sectional view of a portion of a conduit system, including the distal portion of a light guide, in one embodiment;

[0045] Figure 13 This is a schematic cross-sectional view of a portion of a conduit system, including the distal portion of a light guide, in one embodiment;

[0046] Figure 14 This is a schematic cross-sectional view of a portion of a conduit system, including the distal portion of a light guide, according to another embodiment.

[0047] Figure 15 This is a schematic cross-sectional view of a portion of a conduit system, including the distal portion of the light guide, in yet another embodiment;

[0048] Figure 16 This is a simplified schematic side view of a portion of an embodiment of a conduit that includes a portion of a plasma target;

[0049] Figures 16A to 16J Is Figure 16 Cross-sectional views of various embodiments of the plasma target taken along line 16-16 in the diagram;

[0050] Figures 17A to 17HA perspective view of various embodiments of a plasma target having a target surface;

[0051] Figure 18 This is a cross-sectional view of a portion of a catheter system, including a portion of the catheter, in one embodiment;

[0052] Figure 19 This is a cross-sectional view of a portion of a catheter system, which is another embodiment including a portion of a catheter.

[0053] Figure 20 A cross-sectional view of a portion of a catheter system, including a portion of a catheter, according to another embodiment; and

[0054] Figure 21 This is a cross-sectional view of a portion of a catheter system, which is another embodiment including a portion of a catheter.

[0055] While the embodiments are adaptable to various modifications and alternatives, their specific details have been shown by way of example in the accompanying drawings and will be described in more detail. However, it should be understood that the scope of the invention is not limited to the particular aspects described. Rather, it is intended to cover modifications, equivalents, and alternatives that fall within the spirit and scope of this document. Detailed Implementation

[0056] Treating vascular disease can reduce major adverse events or death in affected subjects. A major adverse event is an event that can occur in any part of the body due to the presence of vascular disease. Major adverse events may include, but are not limited to, major adverse cardiac events, major adverse events of the peripheral or central vascular system, major adverse events of the brain, major adverse events of muscle tissue, or major adverse events of any internal organ.

[0057] In various embodiments, the systems and methods disclosed herein describe the use of a catheter system comprising any number of optical guides to generate pressure waves in an inflatable balloon (sometimes referred to herein simply as a "balloon") to rupture intravascular lesions. The catheter system of this document can utilize optical energy to generate plasma near the optical guides positioned within the inflatable balloon at or near the treatment site. As used herein, the treatment site can include vascular lesions, such as calcified vascular lesions or fibrotic vascular lesions (sometimes referred to herein simply as "lesions"), which are common in blood vessels and / or heart valves. The formation of plasma may induce pressure waves and may induce the rapid formation of one or more bubbles that can rapidly expand to their maximum size and subsequently dissipate via cavitation events, which may also initiate pressure waves upon collapse. The rapid expansion of the plasma-induced bubbles can generate one or more pressure waves within the balloon fluid, thereby applying pressure waves to the treatment site. The pressure waves can transfer mechanical energy to the treatment site through the incompressible balloon fluid to exert a rupture force on the lesion. Without being bound by any particular theory, it is believed that rapid changes in the fluid momentum of the balloon in the balloon wall of an inflatable balloon that is in contact with or located near the lesion can be transmitted to the lesion to induce rupture within it.

[0058] The catheter system may include a catheter configured to be advanced to a lesion located within or adjacent to a blood vessel, wherein the catheter includes a catheter axis. The catheter also includes one or more optical guides disposed along the catheter axis and within a balloon. Each optical guide may be configured to be optically connected to a light source and / or a power source.

[0059] Those skilled in the art will recognize that the following detailed description of the invention is merely illustrative and not intended to be limiting in any way. Other embodiments of the invention will readily conceive of those skilled in the art upon benefiting from this disclosure. Additionally, other methods of delivering energy to lesions can be utilized, including but not limited to current-induced plasma generation. Reference will now be made in detail to embodiments of the invention as illustrated in the accompanying drawings.

[0060] For clarity, not all conventional features of the embodiments described herein are shown or described. It should be understood, of course, that in developing any such practical implementation, many implementation-specific decisions must be made to achieve the developer’s specific objectives, such as compliance with application-related and business-related constraints, and that these specific objectives will vary depending on the implementation and the developer. Furthermore, it should be understood that such development work can be complex and time-consuming, but remains a routine engineering task for those skilled in the art who will benefit from this invention.

[0061] In some embodiments, the light guide may be configured to include one or more steering features configured to direct light from the light guide toward a side surface of the light guide and toward the balloon wall. The steering features may direct light in a direction away from the axis of the light guide or in an off-axis direction. Additionally or alternatively, each light guide may include one or more optical windows disposed along a longitudinal or axial surface of each light guide and in optical communication with the steering features. The optical windows may include a portion of the light guide that allows light to exit from the light guide within the light guide, such as a portion of the light guide lacking cladding material on or around the light guide. The inflatable balloon described herein may be coupled to a catheter shaft and / or other structures and may be inflated with balloon fluid.

[0062] The inflatable balloon may include a balloon wall and can be configured to expand from a constricted state suitable for advancing a catheter through a patient's vascular system to an inflated state suitable for anchoring the catheter in place relative to the treatment site. The power source can be configured to provide sub-millisecond pulses of light to induce plasma generation in the balloon fluid within the balloon, resulting in rapid bubble formation and the application of pressure waves at the treatment site.

[0063] Various embodiments of the present invention irradiate laser energy onto a plasma target to induce plasma generation via interaction with the plasma target material, rather than optically breaking down the fluid in the balloon, thereby moving the creation of plasma away from the distal end of the optical fiber (optical guide). This can be achieved by positioning the plasma target at a distal end away from the optical fiber to absorb the light energy and convert it into plasma at a distance away from the optical guide.

[0064] As used herein, the terms “intraperivascular lesion” and “vascular lesion” are used interchangeably unless otherwise stated.

[0065] It should be understood that the catheter systems described herein can include many different forms. Now refer to Figure 1 A schematic cross-sectional view of a catheter system according to various embodiments herein is shown. The catheter system 100 is adapted to apply pressure to induce rupture in vascular lesions within or adjacent to the vessel wall. Figure 1 In the illustrated embodiment, the conduit system 100 may include one or more of a conduit 102, one or more light guides 122, a power supply 124, a manifold 136, and a fluid pump 138.

[0066] The catheter 102 includes an inflatable balloon 104 (sometimes referred to herein as a "balloon"). The catheter 102 is configured to move to a treatment site 106 within or adjacent to a blood vessel 108. For example, the treatment site 106 may include a vascular lesion, such as a calcified vascular lesion. Alternatively or additionally, the treatment site 106 may include a vascular lesion, such as a fibrotic vascular lesion.

[0067] The catheter 102 may include a balloon 104, a catheter shaft 110, and a guidewire 112. The balloon may be coupled to the catheter shaft 110. The balloon may include a proximal balloon 104P and a distal balloon 104D. The catheter shaft 110 may extend between a proximal shaft 114 and a distal shaft 116. The catheter shaft 110 may include a guidewire lumen 118 configured to move on the guidewire 112. The catheter shaft 110 may also include an inflation lumen (not shown). In some embodiments, the catheter 102 may have a distal opening 120 and may receive and move on and / or along the guidewire 112, such that the balloon 104 is positioned at or near a treatment site 106.

[0068] The conduit shaft 110 of conduit 102 may surround one or more optical guides 122 (for clarity, in...) Figure 1 Only one light guide 122 is shown, which is optically connected to the power source 124. The light guide 122 may be disposed at least partially along and / or within the conduit shaft 110, and at least partially within the balloon 104. In various embodiments, the light guide 122 may be an optical fiber, and the power source 124 may be a laser. The power source 124 may be optically connected to the light guide 122. In some embodiments, the conduit shaft 110 may surround multiple light guides, such as a second light guide, a third light guide, etc.

[0069] Balloon 104 may include a balloon wall 130. Balloon 104 can expand from a collapsed configuration suitable for advancing at least a portion of the catheter shaft 102 through the patient's vascular system to an expanded configuration suitable for anchoring the catheter 102 to a suitable position relative to the treatment site 106. A power source 124 of the catheter system 100 can be configured to provide sub-millisecond pulses of light from the power source 124 to a location within balloon 104 along a light guide 112. The light pulses generate light energy, thereby inducing plasma formation within the balloon fluid 132 of balloon 104. Plasma formation results in rapid bubble formation and applies a pressure wave to the treatment site 106. An exemplary plasma-induced bubble... Figure 1 The bubble 134 is shown in the middle. The fluid 132 in the balloon can be a liquid or a gas. As provided in more detail herein, plasma-induced bubbles 134 are intentionally formed at a distance from the light guide 122 to reduce the likelihood of damage to the light guide.

[0070] In various embodiments, sub-millisecond pulses of light can be delivered to the vicinity of the treatment site 106 at a frequency of at least about 1 Hz to up to about 5000 Hz. In some embodiments, sub-millisecond pulses of light can be delivered to the vicinity of the treatment site 106 at a frequency of about 30 Hz to 1000 Hz. In other embodiments, sub-millisecond pulses of light can be delivered to the vicinity of the treatment site 106 at a frequency of at least 10 Hz to 100 Hz. In other embodiments, sub-millisecond pulses of light can be delivered to the vicinity of the treatment site 106 at a frequency of at least about 1 Hz to 30 Hz. In some embodiments, sub-millisecond pulses of light may be delivered to the vicinity of the treatment site 106 at a frequency greater than or equal to 1 Hz, 2 Hz, 3 Hz, 4 Hz, 5 Hz, 6 Hz, 7 Hz, 8 Hz, or 9 Hz, 10 Hz, 20 Hz, 30 Hz, 40 Hz, 50 Hz, 60 Hz, 70 Hz, 80 Hz, 90 Hz, 100 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, 700 Hz, 800 Hz, 900 Hz, 1000 Hz, 1250 Hz, 1500 Hz, 1750 Hz, 2000 Hz, 2250 Hz, 2500 Hz, 2750 Hz, 3000 Hz, 3250 Hz, 3500 Hz, 3750 Hz, 4000 Hz, 4250 Hz, 4500 Hz, 4750 Hz, or 5000 Hz, or at a frequency falling within any of the aforementioned values. Alternatively, sub-millisecond pulses of light can be delivered to the vicinity of the treatment site 106 at a frequency greater than 5000 Hz.

[0071] It should be understood that the catheter system 100 of this invention may include any number of optical guides 122 optically communicated with a power source 124 at the proximal portion 114 and with balloon fluid 132 within the balloon 104 at the distal portion 116. For example, in some embodiments, the catheter system 100 of this invention may include one to five optical guides 122. In other embodiments, the catheter system 100 of this invention may include five to fifteen optical guides. In still other embodiments, the catheter system 100 of this invention may include ten to thirty optical guides. The catheter system 100 of this invention may include 1 to 30 optical guides. It should be understood that the catheter system 100 of this invention may include any number of optical guides falling within a range, wherein any of the aforementioned numbers may be used as the lower or upper limit of the range, provided that the lower limit of the range is less than the upper limit of the range. In some embodiments, the catheter system 100 of this invention may include more than 30 optical guides.

[0072] Manifold 136 may be located at or near the proximal end 114 of the shaft. Manifold 136 may include one or more proximal openings that may receive one or more light guides, such as light guide 122, guidewire 112, and / or inflation conduit 140. Catheter system 100 may also include fluid pump 138 configured to inflate balloon 104 with balloon fluid 132 and / or deflate balloon 104 as needed.

[0073] As with all embodiments shown and described herein, various structures may be omitted from the drawings for clarity and ease of understanding. Furthermore, the drawings may include certain structures that may be omitted, but which do not depart from the spirit and scope of the invention.

[0074] Figure 2 This is a simplified schematic side view of one embodiment of a catheter system 200, including a portion of catheter 202. Figure 2 In the illustrated embodiment, the catheter system may include one or more of an inflatable balloon 204, a guidewire lumen 218, and an optical guide 222. Although Figure 2 The optical guide 222 in (and other embodiments shown and / or described herein) is positioned adjacent to the guidewire lumen 218; however, it should be understood that in some embodiments, the optical guide 222 may be positioned in the guidewire lumen 218 or the catheter shaft 110. Figure 1 As shown in the diagram, the light guide 222 may be incorporated into the guidewire lumen 218 or a portion of the catheter shaft 110. In other embodiments, the light guide 222 may be positioned away from the guidewire lumen 218 and / or the catheter shaft 110. In yet another embodiment, the guidewire lumen 218 may be omitted from the catheter system 200. It should also be appreciated that, for better observation and / or understanding, [the following is an explanation of the design / design]. Figure 2 The structure of the reference characters included in (and other figures shown and described herein) is not necessarily drawn to scale.

[0075] exist Figure 2In the illustrated embodiment, the conduit system 200 further includes a plasma target 242 spaced apart from the distal tip 244 of the light guide 222. The plasma target 242 can be formed of various materials. In some embodiments, the plasma target 242 can be formed of metals and / or metal alloys having relatively high melting temperatures, such as tungsten, tantalum, molybdenum, niobium, platinum, and / or iridium. Alternatively, the plasma target 242 can be formed of at least one of magnesium oxide, beryllium oxide, tungsten carbide, titanium nitride, titanium carbonitride, and titanium carbide. More alternatively, the plasma target 242 can be formed of at least one of diamond CVD and diamond. In other embodiments, the plasma target 242 can be formed of transition metals, alloy metals, or ceramic materials. Still alternatively, in some embodiments, the plasma target 242 can be formed at least partially of polymers, polymeric materials, and / or plastics, such as polyimide and nylon. More alternatively, the plasma target 242 can be formed of any other suitable material. As provided in more detail herein, the geometry, shape, size and / or form of the plasma target 242 may also be varied to suit the design requirements of the conduit system 200.

[0076] exist Figure 2 In the embodiment shown, the light guide 222 emits light energy 243 from its distal tip 244 toward the plasma target 242. Figure 2 (As shown by the dashed line in the diagram). The plasma target 242 is spaced apart from the distal tip 244 of the light guide by a target gap distance 245. The target gap distance 245 can vary. For example, in various embodiments, the target gap distance 245 can be at least 1µm, at least 10µm, at least 100µm, at least 1mm, at least 2mm, at least 3mm, at least 5mm, or at least 1cm. The target gap distance 245 can vary depending on the magnitude, shape, and / or angle of the light energy emitted by the plasma target 242 relative to the light guide 222, the type of material used to form the plasma target 242, the amount and / or duration of the light energy emitted from the light guide 222, the type of balloon fluid 232 used in the balloon 204, etc.

[0077] In some embodiments, the plasma target 242 may be fixed to another structure of the catheter system 200. For example, the plasma target 242 may be fixedly or movably fixed or coupled to the guidewire lumen 218, such as... Figure 2 As shown. Alternatively, the plasma target 242 may be fixedly or movably fixed or coupled to the light guide 222 or another suitable structure. Still alternatively, the plasma target 242 may be suspended (not fixed) within the balloon fluid 232.

[0078] In this design, light energy 243 generates plasma bubbles 234, which create outwardly diverging pressure waves (not shown) impacting the balloon 204 within the entire balloon fluid 232. The impact on the balloon 204 causes the balloon to achieve the treatment site 106. Figure 1 The vascular lesion at the treatment site (shown) is subjected to powerful fragmentation and / or rupture, for example, a calcified vascular lesion. In other words, the rapid formation of the associated plasma bubble 234 and the resulting velocity of the local balloon fluid 232 within the balloon 204 transfer mechanical energy through the incompressible balloon fluid 232 to exert a rupture force on the treatment site 106. The rapid change in momentum of the balloon fluid 232 upon impact with the balloon wall 230 is referred to as a hydraulic shock or water hammer effect. This change in momentum of the balloon fluid 232 is transmitted as a rupture force to the vascular lesion, which is opposite the balloon wall 230.

[0079] Compared to the case where the plasma bubble 234 is generated at or closer to the distal tip 244 of the light guide, the probability of the plasma bubble 234 damaging the light guide 222 is lower by positioning the plasma target 242 away from the distal tip 244 of the light guide 222. In other words, the presence of the plasma target 242, and its positioning away from the distal tip 244 of the light guide 222, causes the plasma bubble 234 to be generated away from the distal tip 244 of the light guide 222, thereby reducing the possibility of damage to the light guide 222. Furthermore, in this embodiment, the positioning of the plasma target 242 can also differ from those described above.

[0080] Figure 3A This is a simplified schematic side view of another embodiment of a catheter system 300, including a portion of a catheter 302, shown in an inflated state. In this embodiment, the catheter 302 includes a balloon 304, a guidewire lumen 318, and one or more optical guides 322. Figure 3A The diagram shows two optical guides 322 and one or more plasma targets 342. Figure 3A Two plasma targets 342 are shown in the image. Figure 3A In the embodiments shown, the light guide 322 may be substantially similar to the light guides previously shown and described herein and / or shown in more detail below.

[0081] However, in this embodiment, the plasma target 242 can move depending on the inflation state of the balloon 304. For example, the plasma target 342 may include a spring, such as a spring-loaded type, which extends outward toward the balloon 304 when the balloon 304 is inflated. In other words, the plasma target 342 can move and / or extend toward the balloon 304 (or in another suitable direction) to better direct the light energy 343 from the light guide 322 toward the plasma target 342. As mentioned above, since the plasma target 342 is positioned away from the distal tip 344 of the light guide 322, the generated plasma bubble 334 is less likely to cause damage to the light guide compared to the case where the plasma bubble 334 is generated at or near the light guide 322.

[0082] Furthermore, in this embodiment, the positioning of the plasma targets 342 can be staggered (staggered with two or more plasma targets 342), such that pressure waves generated from the plasma bubble 334 may impact a larger area of ​​the balloon 304.

[0083] Figure 3B It is indicated as being in a contracted state. Figure 3A A simplified schematic side view of this portion of the catheter is shown. In this embodiment, as the balloon 304 contracts, the plasma target 342 can retract toward the guidewire lumen 318 or in another suitable direction or otherwise move back, such that the catheter 302 can be inserted into and / or removed from the blood vessel 108 during insertion into and / or removal of the catheter 302. Figure 1 As shown), it has a slightly smaller diameter, thereby increasing the ease of insertion and / or removal for the operator of the catheter system 300.

[0084] Figure 4 This is a simplified schematic side view of another embodiment of a catheter system 400, which includes a portion of catheter 402. Figure 4 In the illustrated embodiment, catheter 402 includes balloon 404, guidewire lumen 418, one or more optical guides 422, and one or more plasma targets 442.

[0085] The operation and function of the light guide 422 and the plasma target 442 can be substantially similar to those described above. However, in this embodiment, the light guide 422 can be configured to redirect the light energy 443 in a different direction, i.e., not parallel to the longitudinal axis 470 of the light guide 422. For example, the light energy can be redirected at an angle α relative to the longitudinal axis 470 of the light guide 422. Figure 4In the embodiment shown, the light energy 443 is reoriented in a direction slightly perpendicular to the longitudinal axis 470 of the light guide 422. However, it should be understood that this type of angle is provided only for ease of understanding, and any angle α between 0 degrees and 180 degrees relative to the longitudinal axis 470 of the light guide 422 can be used. The structure and method for reorienting the light energy 443 in this manner are provided in more detail herein.

[0086] Furthermore, in this embodiment, the positioning of the plasma target 442 may differ from those described previously. For example, in one embodiment, the plasma target 442 is positioned between the light guide 422 and the balloon 404. In various embodiments, the plasma target 442 may be fixed or coupled to another structure within the catheter 402, such as the guidewire lumen 418, the light guide 422, the balloon 404, or any other suitable structure. Using this design, the plasma bubble 434 can be generated more closely adjacent to the balloon 404, which may facilitate the application of greater force to break up and / or rupture calcified lesions, and / or maintain the spacing between the plasma bubble 434 formation location and the light guide 422 for the reasons provided herein.

[0087] Figure 5 This is a simplified cross-sectional view of another embodiment of a catheter system 500, which includes a portion of catheter 502. Figure 5 In the illustrated embodiment, the balloon is omitted for clarity. In this embodiment, the catheter 502 includes a guidewire lumen 518, one or more optical guides 522, one or more plasma targets 542, and a target connector 571.

[0088] The operation and function of the light guide 522 and the plasma target 542 can be substantially similar to those described above. However, in this embodiment, the plasma target 542 is coupled to the wire cavity 518 (or another suitable structure) by a target connector 571. In one embodiment, the target connector 571 may be an annular structure that secures the plasma target 542 to the wire cavity 518 (or another structure). Light energy 543 is emitted from the light guide 522 and causes a plasma bubble 534 to be generated at the plasma target 542. Alternatively, the plasma target 542 may be directly adhered to the wire cavity 518 (or another structure) using an adhesive or any other means for securing the plasma target 542. More alternatively, the target connector 571 may be movable, allowing the plasma target 542 to be moved manually or automatically along the wire cavity 518 to change the target gap distance 545 between the plasma target 542 and the distal tip 544 of the light guide 522.

[0089] Alternatively or concurrently, the shape of the plasma target 542 can be varied. For example, in Figure 5In the illustrated embodiment, the plasma target 542 may have a slightly domed or convex shape. Alternatively, the plasma target 542 may have another suitable shape. Using these designs, plasma bubbles 534 can be generated at the plasma target 542, and the plasma target 542 can redirect the generated pressure waves in any desired direction to achieve the desired result.

[0090] Figure 6 This is a simplified schematic side view of another embodiment of a catheter system 600, which includes a portion of catheter 602. Figure 6 In the illustrated embodiment, catheter 602 includes balloon 604, guidewire lumen 618, one or more optical guides 622, and one or more plasma targets 642.

[0091] The operation and function of the light guide 622 and the plasma target 642 can be substantially similar to those previously described. However, in this embodiment, the plasma target 242 is fixed to the inner surface 672 of the balloon 604. Using this design, a plasma bubble is generated away from the light guide 622, thereby reducing the likelihood of damage to the light guide 622. Furthermore, since the plasma target 642 is positioned on the inner surface 672 of the balloon, the balloon will receive a near-direct force from the plasma bubble 634 to increase the breaking force on calcified lesions.

[0092] In this embodiment, the light guide 622 can be configured to redirect the light energy 643 in different directions, i.e., not parallel to the longitudinal axis 670 of the light guide 622. For example, the light energy can be redirected at an angle α relative to the longitudinal axis 670 of the light guide 622. Figure 6 In the embodiment shown, the light energy 643 is reoriented in a direction slightly perpendicular to the longitudinal axis 670 of the light guide 622. However, it should be understood that this type of angle is provided only for ease of understanding, and any angle α between 0 and 180 degrees relative to the longitudinal axis 670 of the light guide 622 can be used. The structure and method for reorienting the light energy 643 in this manner are provided in more detail herein.

[0093] Furthermore, in this embodiment, the positioning of the plasma target 642 may differ from those described previously. For example, in one embodiment, the plasma target 642 is positioned between the light guide 622 and the balloon 604. In various embodiments, the plasma target 642 may be fixed or coupled to another structure within the catheter 602, such as the guidewire lumen 618, the light guide 622, the balloon 604, or any other suitable structure. Using this design, the plasma bubble 634 can be generated more closely adjacent to the balloon 604, which may facilitate the application of greater force to break up and / or rupture calcified lesions, and / or maintain the spacing between the plasma bubble 634 formation location and the light guide 622 for the reasons provided herein.

[0094] Figure 7A This is a simplified schematic side view of another embodiment of a catheter system 700A, which includes a portion of catheter 702A. Figure 7A In the illustrated embodiment, catheter 702A includes balloon 704, guidewire lumen 718, one or more optical guides 722A, and multiple plasma targets 742.

[0095] The operation and function of the light guide 722A and the plasma target 742 can be substantially similar to those described above. However, in this embodiment, the light guide 722A can be configured to guide light energy 743A parallel to the longitudinal axis 770 of the light guide 722B to generate plasma bubbles 734A at multiple plasma targets 742. In this embodiment, the plasma targets 742 are distributed throughout the balloon fluid 732 (in... Figure 7A (Indicated by "X"). In this embodiment, the plasma target 742 can be relatively small, making it easier to suspend in the balloon fluid 732. In various embodiments, the plasma target 742 can float freely within the balloon fluid 732 as a homogeneous or heterogeneous solution. Using this design, one or more plasma bubbles 734A can be generated (in... Figure 7A Only one plasma bubble 734A is shown in the diagram, which may facilitate the application of greater force to break and / or rupture calcified lesions, and / or maintain the spacing between the formation location of the plasma bubble 734A and the light guide 722A for the reasons provided herein.

[0096] Figure 7B This is a simplified schematic side view of another embodiment of a catheter system 700B, which includes a portion of catheter 702B. Figure 7B In the illustrated embodiment, catheter 702B includes balloon 704, guidewire lumen 718, one or more optical guides 722B, and multiple plasma targets 742.

[0097] The operation and function of the light guide 722B and the plasma target 742 can be substantially similar to those described above. However, in this embodiment, the light guide 722B can be configured to redirect the light energy 743B in a different direction, i.e., not parallel to the longitudinal axis 770 of the light guide 722B. For example, the light energy can be redirected at an angle α relative to the longitudinal axis 770 of the light guide 722B. Figure 7B In the illustrated embodiment, the light energy 743B is reoriented in a direction slightly perpendicular to or orthogonal to the longitudinal axis 770 of the light guide 722B. However, it should be understood that this type of angle is provided only for ease of understanding, and any angle α between 0 and 180 degrees relative to the longitudinal axis 770 of the light guide 722B can be used. The structure and method for reorienting the light energy 743B in this manner are provided in more detail herein.

[0098] Furthermore, in this embodiment, the positioning of the plasma target 742 may differ from those described previously. For example, in one embodiment, the plasma target 742 is distributed throughout the entire balloon fluid 732 (in... Figure 7B (Indicated by "X"). In this embodiment, the plasma target 742 can be relatively small, making it easier to suspend in the balloon fluid 732. In various embodiments, the plasma target 742 can float freely within the balloon fluid 732 as a homogeneous or heterogeneous solution. Using this design, one or more plasma bubbles 734B can be generated more closely adjacent to the balloon 704 (in... Figure 7B Only one plasma bubble 734B is shown in the diagram, which can facilitate the application of greater force to break and / or rupture calcified lesions, and / or maintain the spacing between the formation location of the plasma bubble 734B and the light guide 722B for the reasons provided herein.

[0099] Examples of catheters according to various embodiments herein include those having multiple optical guides arranged around the catheter axis at different locations around the circumference, such as... Figures 8 to 11 As shown. It should be understood that, without departing from the intent and / or scope of the invention, multiple light guides may be used in conjunction with any of the embodiments shown and / or described herein.

[0100] Now for reference Figure 8 This illustrates various embodiments of the invention along the path described herein. Figure 1 Line 8-8 Figure 1 A schematic cross-sectional view of the conduit 102 in the diagram. Figure 8The illustrated conduit 802 may include one or more of a conduit shaft 810, a guidewire 812, a guidewire lumen 818, a first light guide 822A, and a second light guide 822B, the second light guide 822B being approximately 180 degrees circumferentially separated from the first light guide 822A. The first light guide 822A includes a side surface, which may include any surface portion surrounding the circumference of the first light guide 822A. The second light guide 822B includes a side surface, which may include any surface portion surrounding the circumference of the second light guide 822B. In some embodiments, the side surface spans a portion of the circumference of the light guide herein, such that it is not a complete cylinder. In other embodiments, the side surface may span the entire circumference of the light guide herein, such that it is cylindrical. It should be understood that any light guide described herein may include a side surface surrounding the circumference of the light guide.

[0101] Now for reference Figures 9 to 11 Figure 3 shows a schematic cross-sectional view of an alternative configuration of a catheter having multiple light guides according to various embodiments herein. An embodiment of the catheter 902 shown in Figure 3 may include a catheter shaft 910, a guidewire 912, a guidewire lumen 918, and one or more of a first light guide 922A, a second light guide 922B, and a third light guide 922C spaced approximately 120 degrees apart around the circumference.

[0102] Figure 10 The embodiment of the catheter 1002 shown includes a catheter shaft 1010, a guidewire 1012, a guidewire lumen 1018, and one or more of a first optical guide 1022A, a second optical guide 1022B, a third optical guide 1022D, and a fourth optical guide 1022D that are spaced about 90 degrees apart around the circumference.

[0103] Figure 11 The illustrated embodiment of catheter 1102 includes a catheter shaft 1110, a guidewire 1112, a guidewire lumen 1118, and one or more of a first optical guide 1122A, a second optical guide 1122B, a third optical guide 1122C, a fourth optical guide 1122D, a fifth optical guide 1122E, and a sixth optical guide 1122F spaced approximately 60 degrees apart around the circumference. It should be understood that more than six optical guides may be used in the embodiments herein.

[0104] It should also be understood that the light guides described herein can be arranged uniformly or non-uniformly around the guide axis to achieve the desired effect at the desired location.

[0105] The following will provide more details and references Figures 12 to 15 Steering and focusing features (sometimes referred to simply as "steering features" herein) are discussed. An optical guide as described herein may include one or more steering features, each of which may be optically connected to the optical guide and is disposed within the optical guide. In some embodiments, the steering feature may be optically connected to the distal end of the optical guide. Reference is now made to... Figures 12 to 15The diagram shows a schematic cross-sectional view of the distal end of an optical guide of various shapes according to various embodiments herein.

[0106] exist Figure 12 The diagram shows a schematic cross-sectional view of the light guide 1222. The light guide 1222 is configured such that light 1254 passes through the proximal end 114 of the axis (…). Figure 1 As shown) in the direction from the power supply 124 to the far top 1244. Figure 1 (As shown) Proceed as indicated by arrow 1254.

[0107] In some embodiments, the ends of the light guide may have an angled shape. For example, in Figure 13 The diagram shows a schematic cross-sectional view of the light guide 1322.

[0108] In some embodiments, the end of the light guide may have a tapered shape. For example, in Figure 14 The diagram shows a schematic cross-sectional view of the light guide 1422.

[0109] Now for reference Figure 15 A schematic cross-sectional view of a light guide 1522 is shown. The light guide 1522 includes an angled end 1558 disposed on a side surface 1562 of a distal end 1564 of the light guide 1522. The light guide 1522 includes a deflection feature 1566 at the distal tip 1544 to guide light energy 1544 within the light guide 1522 toward the side surface 1562 of the light guide 1522. The light guide 1522 is configured such that the light energy 1554 is directed along a longitudinal axis 470 (e.g., as indicated by arrow 1568). Figure 4 The light energy 1554 travels from the distal tip 1544 in a direction at approximately 90 degrees (or another suitable angle), as shown. Upon contact with the deflection feature 1566, the light energy 1554 is deflected or turned within the light guide 1522 to the side surface 1562 of the light guide 1522. The light energy 1554 extends away from the side surface 1562 of the light guide 1522.

[0110] The steering feature 1566 of the light guide 1522 can be made of a reflective element or a refractive element. The steering feature 1566 can be made of glass, polymer, mirror, or reflective metal coating. It should be understood that the angle of internal reflection by the steering feature 1566 can be adjusted by changing the angle of the distal tip 1544 of the light guide 1522.

[0111] In some embodiments, the steering feature may include a light guide to direct light toward a side surface at the distal end of the light guide. The steering feature may include any feature of the system described herein that directs light away from the light guide along its axial path toward a side surface of the light guide. Examples include reflectors, refractive structures, and fiber optic diffusers.

[0112] In some embodiments herein, the light guide may include multiple steering features. For example, each light guide herein may include a first steering feature, a second steering feature, a third steering feature, or a fourth steering feature. In other embodiments, each light guide may include more than four steering features. The steering features may be configured to guide light outwards from a side surface of the light guide toward the balloon wall. In some examples, the steering features guide the light toward the balloon surface closest to the steering feature, such that the light does not cross the longitudinal axis of the guide tube in its path to the balloon surface. It should be understood that the steering features may be optically connected to a corresponding optical window.

[0113] The steering features described herein can be configured to guide light in the light guide through a side surface facing the distal portion, wherein the side surface is optically connected to an optical window. It should be understood that the light guides described herein may each include multiple steering features and multiple optical windows. Examples of steering features suitable for use herein include reflective elements, refractive elements, and / or fiber diffusers.

[0114] Figure 16 This is a simplified schematic side view of a portion of a conduit, comprising a portion of a light guide 1622 and a portion of a plasma target 1642. The plasma target 1642 includes a target surface 1672. The target surface 1672 can have any suitable geometry, shape, or morphology. In this embodiment, the light guide 1622 and the plasma target 1642 operate in a manner substantially similar to those previously shown and / or described. However, in this embodiment, the target surface 1672 is angled relative to the longitudinal axis 1670 of the light guide 1622. In other words, the target surface 1672 has an angle α, which can be any angle between 0 and 180 degrees relative to the longitudinal axis 1670 of the light guide 1622.

[0115] Figures 16A to 16J This is a cross-sectional view illustrating a representative, non-exclusive, and non-limiting embodiment of the cross-sectional shape of the plasma target 1642. It should be understood that the plasma target 1642 has virtually an infinite number of possible cross-sectional shapes, and it is impossible to show and describe all such shapes. However, the scope of the invention is intended to encompass all such possible shapes, even those not shown and / or described herein.

[0116] Figure 16A Is Figure 16 A cross-sectional view of one embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially circular cross-sectional shape.

[0117] Figure 16B Is Figure 16A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially vertical elliptical or elliptical cross-sectional shape.

[0118] Figure 16C Is Figure 16 A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially square cross-sectional shape.

[0119] Figure 16D Is Figure 16 A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a cross-sectional shape that is substantially rhomboid, trapezoidal, or parallelogram-shaped.

[0120] Figure 16E Is Figure 16 A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially hexagonal cross-sectional shape.

[0121] Figure 16F Is Figure 16 A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially horizontal elliptical or elliptical cross-sectional shape.

[0122] Figure 16G Is Figure 16 A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially pentagonal cross-sectional shape.

[0123] Figure 16H Is Figure 16 A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially octagonal cross-sectional shape.

[0124] Figure 16I Is Figure 16 A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially vertical rectangular cross-sectional shape.

[0125] Figure 16J Is Figure 16A cross-sectional view of another embodiment of the plasma target 1642, taken along line 16-16. In this embodiment, the plasma target 1642 has a substantially horizontal rectangular cross-sectional shape.

[0126] Figures 17A to 17H This is a perspective view illustrating a representative, non-exclusive, and non-limiting embodiment of the geometry, shape, and / or morphology of the target surface 1772A-H of the plasma target 1742A-H. It should be understood that the target surface 1772A-H of the plasma target 1742A-H has an infinite number of possible cross-sectional shapes, and it is impossible to show and describe all such shapes. However, the scope of the invention is intended to encompass all such possible shapes, even those not shown and / or described herein.

[0127] Figure 17A This is a perspective view of a portion of an embodiment of a plasma target 1742A having a target surface 1772A. In this embodiment, the target surface 1772A has a slightly conical shape.

[0128] Figure 17B This is a perspective view of a portion of an embodiment of a plasma target 1742B having a target surface 1772B. In this embodiment, the target surface 1772B has a slightly pyramidal shape.

[0129] Figure 17C This is a perspective view of a portion of an embodiment of a plasma target 1742C having a target surface 1772C. In this embodiment, the target surface 1772C has a slightly convex or dome shape.

[0130] Figure 17D This is a perspective view of a portion of an embodiment of a plasma target 1742D having a target surface 1772D. In this embodiment, the target surface 1772D has a slightly concave shape.

[0131] Figure 17E This is a perspective view of a portion of an embodiment of a plasma target 1742E having a target surface 1772E. In this embodiment, the target surface 1772E includes a helical portion 1774 extending outward from a side portion 1776 of the plasma target 1742E.

[0132] Figure 17F This is a perspective view of a portion of an embodiment of a plasma target 1742F having a target surface 1772F. In this embodiment, the target surface 1772F has a slightly spring-like or spiral shape.

[0133] Figure 17GThis is a perspective view of a portion of an embodiment of a plasma target 1742G having a target surface 1772G. In this embodiment, the target surface 1772G has an oblique cut shape.

[0134] Figure 17H This is a perspective view of a portion of an embodiment of a plasma target 1742H having a target surface 1772H. In this embodiment, the target surface 1772H includes one or more surface features 1778. Surface features 1778 may include pits, recesses, or notches extending into the target surface 1780 of the target surface 1772H. Additionally or alternatively, surface features 1778 may include protrusions extending outward from the target surface 1780 of the target surface 1772H. In one embodiment, surface features 1778 may include the same material or other materials added to the target surface 1780. The specific size and / or shape of the surface features 1778 may vary.

[0135] Figure 18 This is a cross-sectional view of a portion of a catheter system 1800, including a portion of a catheter 1802, according to one embodiment. In this embodiment, the catheter 1802 may include a portion of a guidewire lumen 1818, one or more light guides 1822, and a plasma target 1842. The plasma target 1842 is spaced apart from the light guides 1822 and includes a target facet 1872. The target facet 1872 may have any suitable geometry, shape, or morphology. In this embodiment, the light guides 1822 and the plasma target 1842 operate in a manner substantially similar to those previously shown and / or described. However, in this embodiment, the plasma target 1842 may be annular and may surround the circumference of the guidewire lumen 1818. Furthermore, the target facet 1872 of the plasma target 1842 may have a slightly concave, conical shape. In alternative, non-exclusive embodiments, the plasma target 1842 may have a beveled, annular, or truncated conical shape, or any other suitable shape. In an alternative embodiment, the plasma target 1842 only partially surrounds the guidewire lumen 1818. Alternatively, the plasma target 1842 may surround or partially surround another structure of the conduit 1802.

[0136] Figure 19This is a cross-sectional view of a portion of a catheter system 1900, including a portion of a catheter 1902, according to one embodiment. In this embodiment, the catheter 1902 may include a portion of a guidewire lumen 1918, one or more light guides 1922, and a plasma target 1942. The plasma target 1942 is spaced apart from the light guides 1922 and includes a target surface 1972. The target surface 1972 may have any suitable geometry, shape, or morphology. In this embodiment, the light guides 1922 and the plasma target 1942 operate in a manner substantially similar to those previously shown and / or described. However, in this embodiment, the plasma target 1942 may be annular and may surround the circumference of the guidewire lumen 1918. Furthermore, the target surface 1972 of the plasma target 1942 may have a slightly conical or pyramidal shape. In an alternative embodiment, the plasma target 1942 only partially surrounds the guidewire lumen 1918. More alternatively, the plasma target 1942 may surround or partially surround another structure of the catheter 1902.

[0137] Figure 20 This is a cross-sectional view of a portion of a catheter system 2000, including a portion of a catheter 2002, according to one embodiment. In this embodiment, the catheter 2002 may include a guidewire lumen 2018, two or more optical guides 2022 (in... Figure 20 Only one embodiment of two light guides 2022 and a portion of a plasma target 2042 is shown. The plasma target 2042 is spaced apart from the light guides 2022 and includes a target surface 2072. The target surface 2072 can have any suitable geometry, shape, or morphology. In this embodiment, the light guides 2022 and the plasma target 2042 operate in a manner substantially similar to those previously shown and / or described. In an alternative embodiment, two or more plasma targets 2042 may be attached to the guidewire cavity 2018, with each only partially surrounding the guidewire cavity 2018. More alternatively, the plasma target 2042 may surround or partially surround another structure of the catheter 2002. It should be understood that more than two light guides 2022 can be used with the catheter system 2000 of this document. For example, three light guides 2022 may be uniformly spaced apart from each other at 120 degrees; four light guides 2022 may be uniformly spaced apart from each other at 90 degrees. Alternatively, any number of optical guides 2022 can be positioned such that they are non-uniformly spaced around the guide wire cavity 2018.

[0138] Figure 21 This is a cross-sectional view of a portion of a catheter system 2100, including a portion of catheter 2102, according to one embodiment. In this embodiment, catheter 2102 may include a guidewire lumen 2118, and two or more optical guides including a first optical guide 2122F and a second optical guide 2122S. Figure 21Only two optical guides are shown in the image), and two or more plasma targets including a first plasma target 2142F with a first target surface 2172F and a second plasma target 2142S with a second target surface 2172S (in Figure 21 Only two plasma targets are shown in the image. Figure 21 In the illustrated embodiment, a first light guide 2122F emits light energy to generate a first plasma bubble 2134F at or near a first target surface 2172F of a first plasma target 2142F. A second light guide 2122S emits light energy to generate a second plasma bubble 2134S at or near a second target surface 2172S of a second plasma target 2142S spaced apart from the first plasma target 2142F. Figure 21 In the illustrated embodiment, the second optical guide 2122S extends through the first plasma target 2142F. Alternatively, the second optical guide 2122S may pass around the first plasma target 2142F. More alternatively, any or all of the plasma targets 2142F and 2142S may surround or partially surround the guide wire cavity 2118.

[0139] balloon

[0140] Balloons suitable for the catheter systems shown and / or described herein include those that can pass through a patient's vascular system when in a collapsed configuration. In some embodiments, the balloons shown and / or described herein may be made of silicone. In other embodiments, the balloons herein are made of polydialkylsiloxane (PDMS), polyurethane, polymers such as PEBAX™ material available from Arkema, King Prussia, Pennsylvania, USA, nylon, etc. In some embodiments, the balloons may include those with a diameter ranging from 1 mm to 25 mm. In some embodiments, the balloons may include those with a diameter ranging from at least 1.5 mm to 12 mm. In some embodiments, the balloons may include those with a diameter ranging from at least 1 mm to 5 mm. In some embodiments, the diameter may be greater than or equal to 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, 10.0 mm, 10.5 mm, 11.0 mm, 11.5 mm, 12.0 mm, 12.5 mm, 13.0 mm, 13.5 mm, 14.0 mm, 14.5 mm, 15.0 mm, 15.5 mm, 16.0 mm, 16.5 mm, 17.0 mm, 17.5 mm, 18.0 mm, 18.5 mm, 19.0 mm, 19.5 mm, or 20.0 mm, or may be an amount falling within any of the foregoing values.

[0141] In some embodiments, the balloons shown and / or described herein may include those with a length ranging from at least 5 mm to 300 mm. In some embodiments, the balloons shown and / or described herein may include those with a length ranging from at least 8 mm to 200 mm. In some embodiments, the length of the balloon may be greater than or equal to 5 mm, 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, 210 mm, 220 mm, 230 mm, 240 mm, 250 mm, 260 mm, 270 mm, 280 mm, 290 mm, or 300 mm, or may be an amount falling within any of the foregoing values.

[0142] The balloon shown and / or described herein can inflate to an inflation pressure of 1 atmosphere (atm) to 70 atm. In some embodiments, the balloon shown and / or described herein can inflate to an inflation pressure of at least 20 atm to 70 atm. In some embodiments, the balloon shown and / or described herein can inflate to an inflation pressure of at least 6 atm to 20 atm. In some embodiments, the balloon shown and / or described herein can inflate to an inflation pressure of at least 3 atm to 20 atm. In some embodiments, the balloon shown and / or described herein can inflate to an inflation pressure of at least 2 atm to 10 atm. In some embodiments, the balloon shown and / or described herein can be inflated to an inflation pressure greater than or equal to 1 atm, 2 atm, 3 atm, 4 atm, 5 atm, 6 atm, 7 atm, 8 atm, 9 atm, 10 atm, 15 atm, 20 atm, 25 atm, 30 atm, 35 atm, 40 atm, 45 atm, 50 atm, 55 atm, 60 atm, 65 atm, or 70 atm, or can be an amount falling within any of the foregoing values.

[0143] The balloons shown and / or described herein may include those having various shapes, including but not limited to those that are conical, square, rectangular, spherical, conical / square, conical / spherical, extended spherical, elliptical, conical, bony, stepped diameter, offset, or conical offset. In some embodiments, the balloons shown and / or described herein 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, antitumor agents, anti-angiogenic agents, etc.

[0144] balloon fluid

[0145] The exemplary balloon fluids suitable for use herein may include, but are not limited to, one or more of water, saline, contrast media, fluorocarbons, perfluorocarbons, gases (such as carbon dioxide), etc. In some embodiments, the balloon fluids shown and / or described herein may be used as the base inflation fluid, which will be discussed elsewhere herein. In some embodiments, the balloon inflation fluid comprises a mixture of saline and contrast media in a 50:50 volume ratio. In some embodiments, the balloon fluid comprises a mixture of saline and contrast media in a 25:75 volume ratio. In some embodiments, the balloon fluid comprises a mixture of saline and contrast media in a 75:25 volume ratio. The balloon fluids suitable for use herein may be adjusted based on composition, viscosity, etc., to manipulate the travel rate of pressure waves herein. The balloon fluids suitable for use herein are biocompatible. The volume of the balloon fluid may be adjusted depending on the selected power source and the type of balloon fluid used.

[0146] In some embodiments, the contrast agents used in the contrast media herein may include, but are not limited to, iodine-based contrast agents, such as ionic or nonionic iodine-based contrast agents. Some non-limiting examples of ionic iodine-based contrast agents include diatrizoate, methyldiatrizoate, iodophthalate, and iodixanol. Some non-limiting examples of nonionic iodine-based contrast agents include iopamidol, iohexol, ioxilan, iopromide, iodixanol, and iofluoxetine. In other embodiments, non-iodine-based contrast agents may be used. Suitable non-iodine-based contrast agents may include gadolinium (III)-based contrast agents. Suitable fluorocarbon and perfluorocarbon reagents may include, but are not limited to, reagents such as perfluorocarbon dodecylfluoropentane (DDFP, C5F12).

[0147] The balloon fluid shown and / or described herein may include those comprising an absorbent that selectively absorbs light in the ultraviolet region of the electromagnetic spectrum (e.g., at least 10 nanometers (nm) to 400 nm), the visible region (e.g., at least 400 nm to 780 nm), and the near-infrared region (e.g., at least 780 nm to 2.5 µm), or in the far-infrared region of the electromagnetic spectrum at least 10 nm to 2.5 micrometers (µm). Suitable absorbents may include those having an absorption maximum along a spectrum at least 10 nm to 2.5 µm. In various embodiments, the absorbent may be those having an absorption maximum that matches the emission maximum of a laser used in a catheter system. As a non-limiting example, 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). In some embodiments, the absorbent used herein may be water-soluble. In other embodiments, the absorbent used herein may not be water-soluble. In some embodiments, the absorbent in the balloon fluid used herein may be adjusted to match the peak emission of the power source. Various power sources with emission wavelengths of at least 10 nanometers to 1 millimeter will be discussed elsewhere herein.

[0148] In some embodiments, the introduction of balloon fluid causes the balloon to expand from a collapsed state to a first expanded state, and from the first expanded state to a second further expanded state. Alternatively or alternatively, shape memory materials or other methods can be used to achieve balloon expansion.

[0149] Light guide

[0150] The optical guides shown and / or described herein may include optical fibers or flexible light guides. The optical guides shown and / or described herein may be thin and flexible, and may allow the transmission of optical signals with very little intensity loss. The optical guides shown and / or described herein may include a fiber core surrounded by a cladding around its circumference. In some embodiments, the fiber core may be a cylindrical or partially cylindrical fiber core. The fiber core and cladding of the optical guide 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 optical guide may also include a protective coating, such as a polymer. It should be understood that the refractive index of the fiber core will be greater than the refractive index of the cladding.

[0151] Each light guide can direct light along its length to a distal portion having at least one optical window. Light guides can create an optical path as part of an optical network that includes a power source. An optical path within an optical network allows light to travel from one part of the network to another. Both optical fibers and flexible light guides can provide an optical path within the optical network described herein.

[0152] The light guides shown and / or described herein can take various forms around the catheter axis shown and / or described herein. In some embodiments, the light guide may travel parallel to the longitudinal axis of the catheter axis. In some embodiments, the light guide may be arranged in a helical or spiral shape around the longitudinal axis of the catheter axis. In some embodiments, the light guide may be physically coupled to the catheter axis. In other embodiments, the light guide may be arranged along the length of the outer diameter of the catheter axis. In other embodiments, the light guides described herein may be disposed within one or more light guide cavities within the catheter axis. Various forms of the catheter axis and light guide cavities will be discussed below.

[0153] Steering characteristics and focusing characteristics

[0154] The steering features suitable for use herein include reflective elements, refractive elements, and fiber optic diffusers. In some embodiments, the steering feature may be a reflective element. In some embodiments, the steering feature may be a refractive element. In some embodiments, the steering feature may be a fiber optic diffuser.

[0155] An optical fiber diffuser can guide light from within an optical guide so that it exits at a side surface of the optical guide. The optical fiber diffuser described herein can be created in several ways. In some embodiments, the optical fiber diffuser can be created by micromachining the surface of the distal portion of the optical guide using a CO2 laser. In some embodiments, a fused silica coating can be applied to the distal portion of the optical guide. In other embodiments, the optical fiber diffuser can be formed of glass, a polymer, or a metallic coating on the distal portion of the optical guide. In other embodiments, the optical fiber diffuser can be formed of a fiber Bragg grating on the distal portion of the optical guide. In some embodiments, the optical fiber diffuser can include a machined portion of the optical guide, a laser-machined portion of the optical guide, a fiber Bragg grating, a fusion splice, a fusion splice forming at least one internal mirror, and a splice of two or more diffusion regions.

[0156] Materials suitable for fiber optic diffusers can include, but are not limited to, materials for the fiber core or cladding, frosted glass, silver-plated glass, gold-plated glass, TiO2, and other materials that scatter light without significantly absorbing light of the wavelength of interest. One method for creating a uniform diffuser in a light guide, optical component, or material is to utilize scattering centers with a size on the order of at least 50 nanometers to 5 micrometers. The size distribution of the scattering centers can be approximately 200 nanometers.

[0157] The steering and focusing features suitable for focusing light away from the top of the light guide can include, but are not limited to, those with convex surfaces, gradient refractive index (GRIN) lenses, and specular focusing lenses.

[0158] power supply

[0159] The power sources suitable for use herein can include various types of power sources, including lasers and lamps. Suitable lasers can include short-pulse lasers with sub-millisecond timescales. In some embodiments, the power source can include lasers with nanosecond (ns) timescales. Lasers can also include short-pulse lasers with picosecond (ps), femtosecond (fs), and microsecond (µs) timescales. It should be understood that a variety of combinations of laser wavelengths, pulse widths, and energy levels can be employed to achieve plasma in the balloon fluid of the catheters shown and / or described herein. In various embodiments, pulse widths can include those falling within the range of at least 10 ns to 200 ns. In some embodiments, pulse widths can include those falling within the range of at least 20 ns to 100 ns. In other embodiments, pulse widths can include those falling within the range of at least 1 ns to 5000 ns.

[0160] Exemplary nanosecond lasers may include those in the UV to IR spectral range, spanning wavelengths from about 10 nanometers to 1 millimeter. In some embodiments, the power supply for the conduit system suitable for use herein may include those capable of generating light with wavelengths from at least 750 nm to 2000 nm. In some embodiments, the power supply may include those capable of generating light with wavelengths from at least 700 nm to 3000 nm. In some embodiments, the power supply may include those capable of generating light with wavelengths from at least 100 nm to 10 micrometers (µm). Nanosecond lasers may include those with repetition rates up to 200 kHz. In some embodiments, the laser may include a Q-switched thulium:yttrium aluminum garnet (Tm:YAG) laser. In some embodiments, the laser may include neodymium:yttrium aluminum garnet (Nd:YAG), holmium:yttrium aluminum garnet (Ho:YAG), erbium:yttrium aluminum garnet (Er:YAG), excimer lasers, helium-neon lasers, carbon dioxide lasers, and doped pulsed fiber lasers.

[0161] pressure wave

[0162] The catheters shown and / or described herein can generate pressure waves with maximum pressures ranging from at least 1 MPa to 100 MPa. The maximum pressure generated by a particular catheter will depend on the power source, absorbent material, bubble expansion, propagation medium, balloon material, measurement distance from the plasma center, and other factors. In some embodiments, the catheters shown and / or described herein can generate pressure waves with maximum pressures ranging from at least 2 MPa to 50 MPa. In other embodiments, the catheters shown and / or described herein can generate pressure waves with maximum pressures ranging from at least 2 MPa to 30 MPa. In other embodiments, the catheters shown and / or described herein can generate pressure waves with maximum pressures ranging from at least 15 MPa to 25 MPa. In some embodiments, the catheters shown and / or described herein can generate peak pressures greater than or equal to 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa, 10 MPa, 11 MPa, 12 MPa, 13 MPa, 14 MPa, 15 MPa, 16 MPa, 17 MPa, 18 MPa, 19 MPa, 20 MPa, 21 MPa, 22 MPa, 23 MPa, 24 MPa, etc. Pressure waves of 25 MPa, 26 MPa, 27 MPa, 28 MPa, 29 MPa, 30 MPa, 31 MPa, 32 MPa, 33 MPa, 34 MPa, 35 MPa, 36 MPa, 37 MPa, 38 MPa, 39 MPa, 40 MPa, 41 MPa, 42 MPa, 43 MPa, 44 MPa, 45 MPa, 46 MPa, 47 MPa, 48 MPa, 49 MPa, or 50 MPa. It should be understood that the catheters shown and / or described herein can generate pressure waves with operating pressures or maximum pressures that can fall within a range, wherein any of the foregoing quantities can be used as the lower or upper limit of that range, provided that the lower limit of the range is less than the upper limit of the range.

[0163] Treatment can be administered via either a fatigue mechanism or a force mechanism. For a fatigue mechanism, the operating pressure will be at least approximately 0.5 MPa to 2 MPa, or approximately 1 MPa. For a force mechanism, the operating pressure will be at least approximately 20 MPa to 30 MPa, or approximately 25 MPa. Pressures between the extreme endpoints of these two ranges can be applied to the treatment site using a combination of fatigue and force mechanisms.

[0164] The pressure wave described herein can be applied to the treatment site at a distance ranging from at least 0.1 mm to 25 mm, extending radially from the longitudinal axis of the catheter placed at the treatment site. In some embodiments, the pressure wave can be applied to the treatment site at a distance ranging from at least 10 mm to 20 mm, extending radially from the longitudinal axis of the catheter placed at the treatment site. In other embodiments, the pressure wave can be applied to the treatment site at a distance ranging from at least 1 mm to 10 mm, extending radially from the longitudinal axis of the catheter placed at the treatment site. In other embodiments, the pressure wave can be applied to the treatment site at a distance ranging from at least 1.5 mm to 4 mm, extending radially from the longitudinal axis of the catheter placed at the treatment site. In some embodiments, the pressure wave can be applied to the treatment site at a distance ranging from 0.1 mm to 10 mm with a pressure ranging from at least 2 MPa to 30 MPa. In some embodiments, the pressure wave can be applied to the treatment site at a distance ranging from 0.1 mm to 10 mm with a pressure ranging from at least 2 MPa to 25 MPa. In some embodiments, the pressure wave may be applied to the treatment site at a distance greater than or equal to 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, or 0.9 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm, or may be an amount falling within any of the foregoing values.

[0165] It should be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural indicators unless the content and / or context clearly indicate otherwise. It should also be noted that the term “or” is generally used in the sense of including “and / or” unless the content and / or context clearly indicate otherwise.

[0166] It should also be noted that, as used in this specification and the appended claims, the term "configured as" describes a system, device, or other structure constructed or configured to perform a particular task or employ a particular configuration. The term "configured as" may be used interchangeably with other similar phrases, such as arranged and configured as, constructed and arranged as, constructed as, made and arranged as, etc.

[0167] As used herein, a description of a range of numbers represented by endpoints should include all numbers falling into that range, including the endpoints (e.g., 2 to 8 includes 2, 2.1, 2.8, 5.3, 7, 8, etc.).

[0168] It should be recognized that the accompanying drawings shown and described are not necessarily drawn to scale, and are provided for ease of reference and understanding, as well as for the relative positioning of the structures.

[0169] The headings used herein are provided for compliance with the recommendations of 37 CFR 1.77 or otherwise for providing organizational guidance. These headings should not be construed as limiting or characterizing the invention as set forth in any of the claims arising from this disclosure. As an example, the description of the technology in the “Background Art” section does not constitute an endorsement of the fact that “the technology is prior art to any invention of this disclosure.” Nor should the “Summary” or “Abstract” be considered as characterizing the invention as set forth in the claims.

[0170] The embodiments described herein are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the detailed descriptions below. Rather, these embodiments were chosen and described to enable those skilled in the art to understand and appreciate the principles and practices. Therefore, various aspects have been described with reference to specific and preferred embodiments and techniques. However, it should be understood that numerous variations and modifications can be made without departing from the spirit and scope of this document.

[0171] It should be understood that although various different embodiments of the catheter system have been shown and described herein, one or more features of any one embodiment may be combined with one or more features of one or more other embodiments, provided that such combination satisfies the spirit of the invention.

[0172] While several exemplary aspects and embodiments of the catheter system have been discussed above, those skilled in the art will recognize that certain modifications, substitutions, additions, and sub-combinations may be made therein. Therefore, it is intended that the appended claims and subsequent claims be construed as including all such modifications, substitutions, additions, and sub-combinations within their true spirit and scope, and that the details of the constructions or designs shown herein are not limited in any way.

Claims

1. A catheter system for treating a treatment site within or adjacent to a blood vessel, the catheter system comprising: power supply; A light guide that receives power from the power source, the light guide having a distal tip, the light guide emitting light energy in a direction away from the distal tip; An inflatable balloon surrounds the distal tip of the light guide; as well as A plasma target, spaced apart from the distal tip of the light guide by a target gap distance, the plasma target being positioned within the inflatable sac, the plasma target being configured to receive light energy from the light guide such that, upon receiving the light energy from the light guide, plasma is generated at the plasma target, the plasma target being formed at least partially from a polymer and a polymer material.

2. The catheter system according to claim 1, wherein, The power source is a laser.

3. The catheter system according to any one of claims 1 to 2, wherein, The optical guide is an optical fiber.

4. The catheter system according to any one of claims 1 to 3, wherein, The target gap distance is greater than 1µm.

5. The catheter system according to any one of claims 1 to 4, wherein, The target gap distance is greater than 100µm.

6. The catheter system according to any one of claims 1 to 5, wherein, The plasma target has a cross-sectional shape that is basically one of the following: circular, square, rectangular, oval, pentagonal, hexagonal, octagonal, polygonal, trapezoidal or rhomboid.

7. The catheter system according to any one of claims 1 to 6, further comprising a guidewire lumen, wherein the optical fiber is connected to the guidewire lumen.

8. The catheter system according to any one of claims 1 to 7, wherein, The plasma target has a target surface that receives the light energy from the light guide, the target surface being at an angle relative to the direction in which the light energy is emitted to the plasma target.

9. The catheter system according to any one of claims 1 to 8, wherein, The plasma target is also partially formed from one of magnesium oxide, beryllium oxide, tungsten carbide, titanium nitride, titanium carbonitride, and titanium carbide.

10. The catheter system according to any one of claims 1 to 9, wherein, The plasma target is also partially formed of ceramic material.

11. A catheter system for treating a treatment site within or adjacent to a blood vessel, the catheter system comprising: power supply; A light guide that receives power from the power source, the light guide having a distal tip, the light guide emitting light energy in a direction away from the distal tip; An inflatable balloon surrounds the distal tip of the light guide; as well as A plasma target fixed to the light guide, the plasma target being positioned within the inflatable sac, the plasma target being formed at least in part from: (i) a polymer and a polymeric material, and (ii) a tungsten, tantalum, platinum, molybdenum, niobium, and iridium, the plasma target including a target surface spaced apart from the distal tip of the light guide by a target gap distance, the target surface being configured to receive light energy from the light guide such that plasma is generated at the target surface upon receiving the light energy from the light guide, the target surface being angled relative to the direction in which the light energy is emitted to the plasma target.

12. The catheter system of claim 11, wherein, The power source is a laser.

13. The catheter system according to any one of claims 11 to 12, wherein, The optical guide is an optical fiber.

14. The catheter system according to any one of claims 11 to 13, wherein, The target gap distance is greater than 1µm.

15. The catheter system according to any one of claims 11 to 14, wherein, The target gap distance is greater than 100µm.

16. The catheter system according to any one of claims 11 to 15, wherein, The plasma target has a cross-sectional shape that is basically one of the following: circular, square, rectangular, oval, pentagonal, hexagonal, octagonal, polygonal, trapezoidal or rhomboid.

17. The catheter system according to any one of claims 11 to 16, further comprising a guidewire lumen, the optical guide being connected to the guidewire lumen.

18. The catheter system according to any one of claims 11 to 17, wherein, The plasma target is also partially formed from one of magnesium oxide, beryllium oxide, tungsten carbide, titanium nitride, titanium carbonitride, and titanium carbide.

19. The catheter system according to any one of claims 11 to 18, wherein, The plasma target is also partially formed of ceramic material.

20. A catheter system for treating a treatment site within or adjacent to a blood vessel, the catheter system comprising: power supply; A light guide that receives power from the power source, the light guide having a distal tip, the light guide emitting light energy in a direction away from the distal tip; An inflatable balloon surrounds the distal tip of the light guide; as well as A plasma target, spaced apart from the distal tip of the light guide by a target gap distance, the plasma target being positioned within the inflatable sac, the plasma target being configured to receive light energy from the light guide such that, upon receiving the light energy from the light guide, plasma is generated at the plasma target, the plasma target having a substantially circular cross-sectional shape, the plasma target being formed at least in part from: (i) a polymer and a polymeric material, and (ii) a material selected from tungsten, tantalum, platinum, molybdenum, niobium, and iridium.

Images