STAND-OFF CATHETER WITH MULTIPLE LASER-FIRING PORTS

Abstract

A surgical laser delivery systems utilizes a standoff catheter to prevent contact and/or maintain a predetermined spacing between the laser delivery fiber or fiber assembly and the target. The standoff catheter includes multiple side-firing ports. The side-firing ports may include openings of the same or different dimensions, at least one diffuser, and/or at least one lens, to permit the operator to control the degree of vaporization/coagulation and/or vary lasing parameters without having to withdraw the optical fiber from the patient, by rotating or linearly moving the laser or laser assembly with respect the standoff catheter. The side-firing ports may also include an opening at the front of the stand-off catheter to enable use with a forward-firing laser fiber or fiber assembly.

Claims

1. A stand-off catheter, comprising: a cylindrical or generally cylindrical main body through which an optical fiber or fiber assembly is inserted to perform a surgical laser procedure, wherein the main body includes at least two side openings, each configured to permit passage of a laser beam when the optical fiber or fiber assembly is a side-firing surgical laser fiber or fiber assembly selectively positioned to fire through a respective one of the at least two side openings.

2. A stand-off catheter as claimed in claim 1, wherein the at least two side openings are arrayed in a direction parallel to a cylinder axis of the main body.

3. A stand-off catheter as claimed in claim 1, wherein the at least two side openings are arranged circumferentially around the main body.

4. A stand-off catheter as claimed in claim 1, wherein the at least two side openings have mutually different dimensions.

5. A stand-off catheter as claimed in claim 1, wherein at least two of the side openings have same dimensions.

6. A stand-off catheter as claimed in claim 1, wherein the side openings are formed as pre-drilled sections that pop out when the laser beam is fired at a respective section during the surgical laser procedure.

7. A stand-off catheter as claimed in claim 1, wherein an end of the stand-off catheter is open to permit passage of a laser beam from a forward-firing laser.

8. A stand-off catheter as claimed in claim 7, wherein the open end of the stand-off catheter has a diameter that is smaller than an inner diameter of the main body to form a narrowed opening and a shoulder that limits movement of the optical fiber or optical fiber assembly in the forward direction.

9. A stand-off catheter as claimed in claim 8, wherein the narrowed opening is formed by a plug that fits into the front end of the stand-off catheter.

10. A stand-off catheter, comprising: a cylindrical or generally cylindrical main body through which an optical fiber or fiber assembly is inserted to perform a surgical laser procedure, wherein the main body includes at least one side opening and at least one diffuser or lens, each configured to permit passage of a laser beam when the optical fiber or fiber assembly is a side-firing surgical laser fiber or fiber assembly selectively positioned to fire through a respective one of the at least one side opening and at least one diffuser or lens.

11. A stand-off catheter as claimed in claim 10, wherein the at least one side opening and at least one diffuser or lens are arrayed in a direction parallel to a cylinder axis of the main body.

12. A stand-off catheter as claimed in claim 10, wherein the at least one side opening and at least one diffuser or lens are arranged circumferentially around the main body.

13. A stand-off catheter as claimed in claim 10, wherein the at least one side opening is formed as a pre-drilled section that pops out when the laser beam is fired at the section during the surgical laser procedure.

14. A stand-off catheter as claimed in claim 10, wherein an end of the stand-off catheter is open to permit passage of a laser beam from a forward-firing laser.

15. A stand-off catheter as claimed in claim 14, wherein the open end of the stand-off catheter has a diameter that is smaller than an inner diameter of the main body to form a narrowed opening and a shoulder that limits movement of the optical fiber or optical fiber assembly in the forward direction.

16. A stand-off catheter as claimed in claim 15, wherein the narrowed opening is formed by a plug that fits into the front end of the stand-off catheter.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIGS. 1-3 are isometric views showing variations of a first preferred embodiment of the invention.

[0026] FIG. 4 includes cross-sectional side views of a stand-off catheter according to the first preferred embodiment, into which a side-firing laser assembly and a forward-firing laser assembly have been respectively inserted.

[0027] FIG. 5 is an isometric view of a second preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Throughout the following description and drawings, like reference numbers/characters refer to like elements. It should be understood that, although specific exemplary embodiments are discussed herein there is no intent to limit the scope of present invention to such embodiments. To the contrary, it should be understood that the exemplary embodiments discussed herein are for illustrative purposes, and that modified and alternative embodiments may be implemented without departing from the scope of the present invention.

[0029] FIGS. 1-3 show stand-off catheters 1a, 1b, and 1b′, each having a cylindrical main body 30, 30′, and 30″ made of ceramic, glass, ETFE, PTFE, etc. that is coupled or affixed to, integral with, part of a catheter, introducer or sleeve 5 through which an optical fiber or optical fiber assembly is inserted. The main bodies 30, 30′, 30″ include respective openings or apertures 2, 3, or 4 that may generally correspond to the radially-extending lasing opening or aperture described in the above-cited U.S. patent application Ser. No. 15/957,085, filed Apr. 19, 2018, which has a size that is too small for a substantial amount of a liquid such as irrigating fluid to pass, but which is just large enough to permit passage of most or all of the laser beam. Such an opening or aperture has the advantage that any liquid present in the path of the beam will be vaporized or turned to steam, forming an air channel from the fiber to the tissue in order to minimize absorption of the laser beam, and therefore optimizing the amount of energy delivered to the tissue for therapeutic purposes.

[0030] Since the size of the opening depends on the cross-sectional dimensions of the beam, i.e., on the beam width, diameter, or Gaussian beam radius (1/e.sup.2 value), a single opening can only be used with a beam having particular dimensions. According to the present invention, however, the stand-off catheter can be modified for use with beams having different dimensions, by providing an array or series of the openings or apertures 2, 3, or 4 of different sizes. Larger beams, for example, will deliver therapeutic radiation over a larger area of tissue, while narrower beams permit more precise energy delivery and/or delivery of radiation having a higher intensity.

[0031] As shown in FIGS. 1-3, the openings 2, 3, and 4 can be arranged linearly or circumferentially around the catheter, and may include multiple apertures or openings or each size, so that the laser can be positioned relative to a desired opening side by either linearly moving the lasing tip of the optical fiber, and/or by rotating the tip. It is also possible for all of the openings or apertures on a single catheter to have the same dimensions, so that when one opening has degraded as a result of lasing, the laser can be positioned to lase through another non-degraded opening without having to replace the catheter.

[0032] Optionally, each of the openings may be formed as a knock out, pre-drilled, or pre-scored section that forms a temporary plug and pops out when exposed to a laser beam. When one opening is used and excessively widened or drilled out by passage of the laser, the laser can be moved to the location of another knock out, which pops out to form an opening of a desired size so that the surgical procedure can continue without undue interruption.

[0033] The distal ends 30, 30′, 30″ of the catheters of FIGS. 1-3 are preferably open to permit passage of irrigation fluid. In addition, providing open-ended catheters enables each catheter to also be used as a stand-off catheter for forward-firing laser systems, as described by way of example and not limitation in the above-cited copending U.S. patent application Ser. Nos. 15/992,609; 16/234,690; and 16/353,225.

[0034] As illustrated in FIG. 4, the front opening 40 may have a diameter that is narrower than the inner diameter of the remainder of the catheter in order to form a shoulder and limit forward movement of, or facilitate positioning of, a side-firing laser assembly, and also to control the size of the passage when used with a forward-firing laser. When used with a forward-firing laser, an air bubble can be formed in the front opening of passage during lasing to increase energy transfer efficiency. As an example, any of the catheters 1a, 1b, 1b′, and 1c of FIGS. 1-3 and 5 may be provided with a plug having a desired opening size to form the forward-firing lasing passage, with the plugs further being changeable to control the opening size.

[0035] In the embodiment shown in FIG. 5, the catheter 1 c is further provided with at least one diffuser 50 and/or at least one lens 51, which are in addition to aperture 52 corresponding to the one or more openings or apertures 2-4 shown in FIGS. 1-3 and optional front opening 53. The diffuser 50 can be used to intentionally attenuate or diffuse a side-firing laser beam for purposes such as coagulation, allowing the user to switch between a vaporization operation to a coagulation operation by moving the angled tip of the side-firing laser from a position adjacent one of the openings or apertures 52 to a position adjacent the at least one diffuser. On the other hand, the lens 51 can be used to focus, disperse, collimate or direct the laser beam as necessary for the particular procedure in question. If more than one diffuser or lens is provided, further control of the laser beam intensity, direction, and treatment area can be obtained.

[0036] Although the term “catheter” is used herein, it will be appreciated that the catheter may be referred to as an introducer or sleeve, that it is a cylindrical or generally cylindrical structure, and that the catheter may be inserted into the patient directly or via a laser endoscope, cystoscope, or resectoscope. In addition, it will be appreciated by those skilled in the art that the optical fiber, whether in the side or forward-firing configuration, my be included in an optical fiber assembly or be provided with a cap or ferrule through which the laser is fired. Such a cap or ferrule may further be wholly or partly made of a laser-transparent material, or include an opening to permit passage of the laser.