Systems and methods for eccentric nodule tissue acquisition

Abstract

To provide a sampling system for allowing real-time visualization of eccentric pulmonary nodules and allowing a location / orientation of a biopsy needle to be determined prior to its first puncture.SOLUTION: There is provided a field of endoscopy. Specifically, the systems and methods for real-time visualization and sampling of target tissue within body passages are provided. In particular, the system provides real-time visualization of eccentric pulmonary nodules, and allows the location / orientation of a biopsy needle to be determined prior to its first actuation.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the field of endoscopes. More particularly, it relates to a system and method for visualizing and collecting target tissue in real time within a body passage.

Background Art

[0002] Radial endoscopic ultrasound bronchoscopy (R-EBUS) provides a minimally invasive option when clinical findings indicate the need for tissue biopsy within the pulmonary passage. Conventional radial endoscopic ultrasound bronchoscopy-guided transbronchial needle aspiration (TBNA) includes steps of transporting a radial ultrasound probe to a target airway through the working channel of a bronchoscope, visualizing a target lung nodule with the radial endoscopic ultrasound, locking the placement of an access sheath, removing the radial ultrasound probe from the access sheath, and advancing a biopsy needle blindly for the purpose of obtaining cellular material for cytological evaluation. This blind sampling often results in the biopsy needle completely losing sight of the target nodule. To ensure biopsy of the target nodule, medical staff generally repeatedly puncture the biopsy needle into the lung tissue while rotating the endoscope. Repeatedly stabbing the biopsy needle in this way can lead to various unfavorable medical outcomes, such as unnecessarily damaging healthy tissue around the target nodule, reducing bleeding, increasing the likelihood of false-negative results, and increasing the time and cost required for the procedure. Certainly, the inability to obtain a biopsy sample reliably and accurately is particularly problematic in eccentric lung nodules (e.g., those that are offset), which occur in approximately 40% of all lung procedures. For sampling of eccentric lung nodules, it is necessary to bend or flex either a catheter or a biopsy needle within a narrow pulmonary passage.

[0003] Therefore, a system for visualizing eccentric lung nodules in real time can achieve various improvements. For example, this system enables determination of the position or orientation of the biopsy needle before puncture.

Summary of the Invention

[0004] In various aspects, the present invention relates to a sampling system that enables real-time visualization of eccentric pulmonary nodules in the medical field such as the field of pulmonary endoscopy, and that enables determination of the position or direction of a biopsy needle before puncture. In various embodiments, the present invention discloses a biased biopsy needle and a radial ultrasonic transducer that enable accurate and efficient biopsy of eccentric pulmonary nodule tissue.

[0005] In one aspect, the present invention relates to an end cap comprising a proximal end, a distal end, a first lumen extending between the proximal end and the distal end and forming a first opening, and a second lumen extending between the proximal end and the outer surface of the end cap and forming a second opening. The first lumen and the second lumen are separated by an inner wall having various thicknesses. The thickness of the inner wall is decreased from the distal end toward the proximal end to form an inclined surface within the second lumen. The inclined surface may have an angle of about 5 to 10 degrees with respect to the long axis of the end cap. The first lumen is configured to receive an ultrasonic transducer. The second lumen is configured to receive a tissue sampling element. Without limitation, the end cap may contain various materials such as a metal material or a ceramic material.

[0006] In another aspect, the present invention relates to a system comprising a conveying device having a first working channel and a second working channel, and an end cap having a first lumen and a second lumen that respectively form a first opening and a second opening. The proximal end of the end cap is attached to the distal end of the conveying device such that the first working channel is continuous with the first lumen and the second working channel is continuous with the second lumen. The first lumen and the second lumen are separated by an inner wall having various thicknesses, and the thickness of the inner wall is decreased from the distal end towards the proximal end so as to form an inclined surface within the second lumen. The system further comprises an ultrasonic transducer disposed inside the first working channel and the first lumen. The ultrasonic transducer may extend distally beyond the distal end of the end cap. The system may further comprise a tissue sampling element slidably disposed inside the second working channel and the second lumen. The proximal end of the end cap is attached to the distal end of the conveying device by a heat shrink sleeve disposed around the outer surface of the proximal portion of the end cap and the outer surface of the distal portion of the conveying device. The distal portion of the conveying device comprises a pocket inside which the end cap is coupled. The pocket comprises a cutting opening that coincides with the second opening. The ultrasonic transducer is disposed inside a sheath, and a part of the sheath comprises a radiation-impermeable material. The radiation-impermeable material comprises, for example, a strip made of a radiation-impermeable material extending along a certain length of the sheath. A part of the sheath extends distally beyond the ultrasonic transducer. The strip made of the radiation-impermeable material and the second opening on the outer surface of the end cap may be offset at an angle of about 180 degrees.

[0007] In another aspect, the present invention relates to a method, comprising the step of advancing a tissue sampling system through a body passageway, the tissue sampling system including a delivery device comprising an end cap having a first working channel and a second working channel, and a first lumen and a second lumen forming a first opening and a second opening respectively, the proximal end of the end cap being attached to the distal end of the delivery device such that the first working channel is continuous with the first lumen and the second working channel is continuous with the second working channel, the method further comprising the steps of imaging a target tissue within the body passageway, advancing a tissue sampling element distally into the target tissue beyond the second opening of the end cap such that a portion of the target tissue is captured within the lumen of the tissue sampling element, and removing the system from the body passageway. The target tissue can be imaged under ultrasound using an ultrasound transducer. The tissue sampling element can be advanced into the target tissue while imaging the target tissue.

[0008] Non-limiting examples of the present invention will be described with reference to the accompanying drawings. The drawings are schematic and are not intended to be drawn to scale. In the drawings, the same or substantially the same components are generally denoted by a single numeral. For the purposes of clarity of illustration, not all components may be shown in the drawings if they are not necessary for those skilled in the art to understand the present invention, and not all components of each embodiment of the present invention may be shown either.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2A

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Figure 5A

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Figure 5C

Figure 5D

Figure 5E

Figure 5F

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Figure 6C

Figure 6D

Mode for Carrying Out the Invention

[0010] Note that the drawings are intended to illustrate general or exemplary embodiments of the present invention. Therefore, the drawings should not be considered as limiting the scope of the present invention. Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

[0011] Before further elaborating on the present invention, it should be understood that the present invention is not limited to the specific embodiments described and can be modified. Also, the terms used in this specification are for the purpose of describing specific embodiments and are not intended to limit beyond the scope of the appended claims. Unless otherwise defined, all technical terms used in this specification have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains. Finally, although embodiments of the present invention will be described with particular reference to real-time visualization and sampling of eccentric pulmonary nodules, the systems and methods described in this specification can be used when collecting biopsy samples from various body lumens, such as the heart, vascular system, circulatory system, gastrointestinal tract system, stomach, esophagus, urogenital system, etc. In various embodiments, the end cap of the catheter is also suitable for use with various sampling instruments (e.g., grasping elements or resection elements, etc.) in addition to the biopsy needle.

[0012] As used in this specification, unless otherwise explicitly stated to the contrary, singular forms such as "a", "an", "the" include plural forms. The terms "comprise", "comprising", "includes", or "including" in this specification indicate the presence of a certain feature, region, element of a step or component, but do not deny the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, or groups thereof.

[0013] As used in this specification, "distal" refers to the end that is farthest from the medical staff when inserting the device into the patient's body, and "proximal" refers to the end that is closest to the medical staff when inserting the device into the patient's body.

[0014] The present invention generally provides a two-lumen catheter end cap that supports the simultaneous use of a tissue sampling element and a radial ultrasound transducer adjacent to each other. By having one of the two lumens in an inclined or diagonal configuration, an eccentric nodule can be sampled without pre-curving the tissue sampling element. The two-lumen end cap is adapted for use with a radial ultrasound transducer configured to visualize a target lung nodule in real time while displaying the placement and orientation of a biopsy needle relative to the radial ultrasound transducer prior to puncture. The two-lumen end cap and the radial ultrasound transducer can also visualize the position and orientation of the target lung nodule and the biopsy needle in real time for subsequent punctures into the same (or different) nodules.

[0015] Refer to FIG. 1. In one embodiment, the present invention provides a catheter end cap 110 comprising a proximal end 112, a distal end 114, a first lumen and second lumens 116, 118 separated by an inner wall 122 having various thicknesses. The first lumen 116 extends between the proximal and distal ends 112, 114 and forms a first opening 116a. The second lumen 118 extends between the proximal end 112 and the outer surface of the end cap 110 and forms a second opening 118a. The first opening and the second opening 116a, 118a are not limited to circular or elliptical shapes and may include various other shapes and configurations. The inner wall 122 having various thicknesses is decreased from the distal end 114 towards the proximal end 112 such that the second lumen 118 forms an inclined surface 122a (e.g., an inclined plane, an obliquely oriented surface). The inclined surface 122a may have any angle in the range of about 5 to 10 degrees relative to the long axis (L1) of the end cap 110. The end cap is formed as a single member from various metals, ceramics, or cured plastic materials well known in the art.

[0016] In one embodiment, the end cap of the present invention is attached to a delivery device (e.g., a catheter). Referring to FIG. 2A, the delivery device 230 includes a distal portion 233 that forms a recess 233a (e.g., a pocket) for receiving the end cap 210. The outer surface 220 of the end cap 210 obtains sufficient interference, i.e., friction, inside the recess 233a to prevent the end cap from coming off during use (e.g., inside a patient's body). Additionally or alternatively, the end cap 210 can be fixed inside the recess 233a by at least any one of suitable welding, soldering, brazing, adhesives, pastes, and resins. The recess 233a further includes a cutout 233b that is aligned with the second opening 218a of the end cap 210. Referring to FIG. 2B, the proximal end 212 of the end cap 210 is attached to the distal end 234 of the delivery device 230 by a sleeve 235 that is disposed around the outer surface of the proximal portion 212a of the end cap 210 and the outer surface of the distal portion 233 of the delivery device 230. The sleeve 235 can cover a portion of the second opening 218a. In one embodiment, the sleeve 235 can include a heat-shrinkable material that secures the end cap 210 to the delivery device 230 without increasing the thickness of the delivery device or the end cap. Additionally or alternatively, the sleeve 235 is fixed to the delivery device and the end cap by interference fit and at least any one of suitable welding, soldering, brazing, adhesives, pastes, or resins.

[0017] Refer to FIG. 3A. When the end cap 310 is fixed to the conveying device 330, the conveying device 330 includes a first working channel 336 and a second working channel 338 such that the first working channel 336 coincides with the first lumen 316 to form a continuous lumen, and the second working channel coincides with the second lumen 318 to form a continuous second lumen. The continuous first working channel 336 and the first lumen 316 can receive an ultrasonic transducer 340 disposed inside a flexible sheath 344. The sheath 344 extends distally beyond the ultrasonic transducer 340 and protects the ultrasonic transducer when the conveying device 330 is advanced through the body path. The sheath 344 can further function as a conduit for intermittently introducing a suitable fluid (e.g., isotonic saline) to enable medical personnel to reliably and accurately transmit ultrasonic energy. In one embodiment, the sheath 344 and the ultrasonic transducer 340 are fixedly disposed inside the continuous first working channel 336 and the first lumen 316. In another embodiment, the sheath 344 and the ultrasonic transducer 340 are slidably disposed inside the continuous first working channel 336 and the first lumen 316. In yet another embodiment, the ultrasonic transducer includes a radial ultrasonic probe rotatably disposed inside the sheath 344. The continuous second working channel 338 and the second lumen 318 can slidably receive a tissue sampling element 350 (e.g., a biopsy needle). Refer to FIG. 3B. When the tissue sampling element 350 exits from the second opening 318a, the tissue sampling element 350 is advanced distally along the inclined surface 322a of the end cap 310 such that the tissue sampling element 350 is biased (e.g., curved) from the longitudinal axis direction of the end cap 310. When the tissue sampling element 350 is moved beyond the distal end 314 of the end cap 310, the tissue sampling element 350 and the ultrasonic transducer 340 are biased at an angle of approximately 180 degrees with respect to each other. In other words, the tissue sampling element 350 exits the second opening 318a at a certain portion of the end cap 310 on the opposite side (e.g., directly above) of the ultrasonic transducer 340.Alternatively, the tissue sampling element and the ultrasonic transducer are offset from each other at an angle of 180 degrees or less (e.g., about 90 degrees, about 100 degrees, about 110 degrees, about 120 degrees, about 130 degrees, about 140 degrees, about 150 degrees, about 160 degrees, about 170 degrees, etc.), or at an angle of 180 degrees or more (e.g., about 190 degrees, about 200 degrees, about 210 degrees, about 220 degrees, about 230 degrees, about 240 degrees, about 250 degrees, about 260 degrees, about 270 degrees, etc.).

[0018] The ultrasonic images according to FIGS. 4A-4B show the morphological differences between a concentric pulmonary nodule (FIG. 4A) occupying the central part of the pulmonary path and an eccentric pulmonary nodule (FIG. 4B) located on the side part of the pulmonary path. Refer to FIGS. 5A-5F. In use, by way of example, a bronchoscope (not shown) is advanced through the trachea and into the bronchial pathway near the target tissue site (e.g., a lung nodule). The delivery device 330 (e.g., a catheter) of FIG. 3A is advanced distally through the working channel of the bronchoscope to image the ultrasonic image of the bronchial pathway. When the delivery device approaches the target tissue site, the ultrasonic transducer 340 can acquire an ultrasonic image of the eccentric nodule 8 (FIG. 5A). As shown in FIG. 5B, the eccentric nodule 8 can be visualized as a dark lesion within the upper left quadrant of the ultrasonic image, as opposed to the ultrasonic transducer 340 being visualized as a dark circle in the center of the ultrasonic image. When the ultrasonic transducer 340 is positioned near the eccentric nodule 8, the healthcare provider moves the tissue sampling element 350 through the second opening 318a of the end cap 310 into the wall of the pulmonary pathway (e.g., can be advanced distally) (FIG. 5C). As shown in FIG. 5D, the tissue sampling element 350 appears in the ultrasonic image when it is moved beyond the ultrasonic transducer 340 (e.g., advanced distally). If the tissue sampling element is advanced and the tissue sampling element does not penetrate the eccentric nodule, the healthcare provider retracts the tissue sampling element 350 into the end cap 310 and rotates the entire delivery device 330 based on the relative positions of the tissue sampling element 350 and the eccentric nodule 8 (FIGS. 5C, 5D) to align the position of the second opening 318a with the eccentric nodule 8 (FIG. 5E), and then moves the tissue sampling element 350 again through the second opening 318a of the end cap 310 and into the eccentric nodule (FIG. 5F). The tissue sampling element 350 is then retracted into the end cap 310, and the delivery device 330 is retracted proximally through the bronchoscope and removed from the patient's body. The biopsy sample of the eccentric nodule is then removed from the lumen inside the tissue sampling element 350 for cytological evaluation.The tissue sampling element 350 of FIG. 5C is shown as penetrating the wall of the bronchial pathway at a site that does not enter the eccentric nodule 8 (e.g., the target nodule is "lost sight of"). However, in various embodiments, the tissue sampling element 350 is moved distally beyond the ultrasonic transducer 340 such that the end (e.g., the sharp portion) of the tissue sampling element 350 is displayed in the ultrasonic image but does not extend into the wall of the bronchial pathway. The medical practitioner rotates the entire transport device 330 to align the position of the tissue sampling element 350 with the eccentric nodule 8, and then moves the tissue sampling element 350 completely, i.e., entirely, into the eccentric nodule 8. The transport system according to FIG. 3A is superior to the conventional needle aspiration system, and at the same time, for the medical practitioner, when the biopsy needle is housed inside the end cap or the transport device (e.g., before being advanced for the first time), it is useful because the position and direction of the biopsy needle can be determined with respect to the target pulmonary nodule.

[0019] Refer to FIG. 6A. In one embodiment, the transport device of FIG. 3A includes an ultrasonic transducer 340 disposed inside a flexible sheath 344, and the sheath 344 further includes a radiopaque material disposed on a strip 346 along a part of its length. For example, the radiopaque material can be integrally formed inside the sheath 344 in an extrusion process. Refer to FIG. 6B. The strip 346 of the radiopaque material provides a radiopaque marker that is visible as a dark portion (e.g., a slice) in the ultrasonic image. As described above, the tissue sampling element 350 exits the second opening 318a of the end cap 310 and extends to the exact opposite side (e.g., directly above, etc.) of the ultrasonic transducer 340. Due to the fixed position of the sheath 344 and the radiopaque strip 346, the medical practitioner can identify the location of the tissue sampling element 350 before driving the tissue sampling element.

[0020] In use, by way of example, a bronchoscope (not shown) is advanced through the trachea and into the bronchial pathway near the target tissue site (e.g., a lung nodule). The delivery device 330 (e.g., a catheter) includes a sheath 344 and a radiopaque strip 346 and is advanced distally through the working channel of the bronchoscope to image the ultrasonic image of the bronchial pathway. When the delivery device approaches the target tissue site, the ultrasonic transducer 340 can image the ultrasonic images of both the eccentric nodule 8 and the radiopaque strip 346 (Figs. 6A, 6B). Thereafter, the delivery device 330 is rotated so that the radiopaque strip 346 and the eccentric nodule 8 appear on the exact opposite side of the ultrasonic image (Fig. 6C). Thereafter, the tissue sampling element 350 is moved through the second opening 318a of the end cap 310 and into the eccentric nodule 8 (Fig. 6D). Depending on the amount of biopsy tissue required, the tissue sampling element 350 can be repeatedly retracted or advanced into the eccentric nodule without concern for surrounding healthy tissue. The tissue sampling element 350 is then retracted into the end cap 310, and the delivery device 330 is retracted proximally into the bronchoscope and removed from the patient's body. The biopsy sample of the eccentric nodule is then removed from the lumen of the tissue sampling element 550 for cytological evaluation.

[0021] The medical device of the present invention is not limited to a bronchoscope and may also include various medical devices for accessing internal pathways, such as catheters, urethroscopes, duodenoscopes, rectoscopes, arthroscopes, cystoscopes, hysteroscopes, and the like.

[0022] Finally, although the embodiments according to the present invention have been described on the premise of being used with a bronchoscope, the delivery device of the present invention can be placed in the patient's body without an accompanying medical device. For example, the medical device can be inserted into the patient's body through the working channel of the medical device itself.

[0023] All of the apparatuses and methods described in this specification and the claims can be manufactured and implemented without conducting more experiments than necessary in light of the present invention. Although the apparatuses and methods according to the present invention have been described as preferred embodiments, those skilled in the art will understand that various changes can be made in the apparatuses, methods, method steps, or order of steps described in this specification without departing from the concept, gist, and scope of the present invention. Therefore, all obvious similar substitution forms and modification forms for those skilled in the art shall fall within the gist, scope, and concept of the present invention defined by the appended claims.

Claims

1. A system comprising: The system includes a delivery device having a first working channel and a second working channel; the system includes a tissue sampling element disposed within the second working channel, the tissue sampling element being actuable between an inactive state and an active state; the system includes an ultrasound transducer disposed within the first working channel, the ultrasound transducer imaging the markers to generate a first radial image when the tissue sampling element is in an inactive state, and imaging the markers and the tissue sampling element to generate a second radial image when the tissue sampling element is in an active state; The system includes an end cap having a first lumen and a second lumen that define a first opening and a second opening, respectively; the first opening is at a distal end of the end cap; the second opening is in an outer surface of the end cap; The proximal end of the end cap is attached to the distal end of the delivery device such that the first working channel is continuous with the first lumen and the second working channel is continuous with the second lumen.

2. The system described in claim 1, wherein the ultrasonic transducer comprises a rotary ultrasonic transducer configured to generate a circumferential radial image of tissue surrounding the end cap.

3. The system described in claim 1, wherein the marker comprises a radiopaque marker positioned on the tissue sampling element.

4. The system described in claim 1, wherein the marker comprises an echogenic marker configured to provide a higher ultrasonic reflectivity than adjacent tissue.

5. The system of claim 1, wherein the tissue sampling element comprises a hollow needle configured to receive a tissue sample.

6. The system described in claim 5, wherein the hollow needle is configured for fine needle aspiration.

7. A system comprising: The system includes a delivery device having a first working channel and a second working channel; the system includes a tissue sampling element disposed within the second working channel, the tissue sampling element being actuable between an inactive state and an active state; the system includes an ultrasound transducer disposed within the first working channel, the ultrasound transducer imaging the markers to generate a first radial image when the tissue sampling element is in an inactive state, and imaging the markers and the tissue sampling element to generate a second radial image when the tissue sampling element is in an active state; The system includes an end cap having a first lumen and a second lumen that define a first opening and a second opening, respectively; the first opening is at a distal end of the end cap; the second opening is in an outer surface of the end cap; a proximal end of the end cap is attached to a distal end of the delivery device such that the first working channel is continuous with the first lumen and the second working channel is continuous with the second lumen; The system, wherein the end cap comprises a distal tip, the distal tip being shaped to facilitate advancement through tissue.

8. The system described in claim 7, wherein the end cap is formed from a material that is substantially transparent to ultrasonic energy.

9. The system described in claim 7, wherein the first lumen and the second lumen extend parallel along the longitudinal axis of the end cap.

10. The system described in claim 7, wherein the marker is circumferentially biased relative to the tissue sampling element around the longitudinal axis of the end cap.

11. The system described in claim 10, wherein the marker is angularly offset from the tissue sampling element by approximately 180 degrees around the longitudinal axis.

12. The system described in claim 7, wherein the end cap is removably coupled to the distal end of the conveying device.

13. A system comprising: The system includes a delivery device having a first working channel and a second working channel; the system includes a tissue sampling element disposed within the second working channel, the tissue sampling element being actuable between an inactive state and an active state; the system includes an ultrasound transducer disposed within the first working channel, the ultrasound transducer imaging the markers to generate a first radial image when the tissue sampling element is in an inactive state, and imaging the markers and the tissue sampling element to generate a second radial image when the tissue sampling element is in an active state; The system includes an end cap having a first lumen and a second lumen that define a first opening and a second opening, respectively; the system comprising a handle coupled to a proximal portion of the transport device, the handle including an actuator for moving the tissue sampling element between the inactivated state and the activated state; the first opening is at a distal end of the end cap; the second opening is in an outer surface of the end cap; The proximal end of the end cap is attached to the distal end of the delivery device such that the first working channel is continuous with the first lumen and the second working channel is continuous with the second lumen.

14. The system described in claim 13, wherein the ultrasonic transducer is configured to image the marker when the tissue sampling element is in an inactive state.

15. The system described in claim 13, wherein the ultrasonic transducer is configured to image both the marker and the tissue sampling element when the tissue sampling element is in an operating state.

16. The system described in claim 13, wherein the marker is positioned proximal to the distal tip of the tissue sampling element.

17. The system described in claim 13, wherein the marker comprises a plurality of bands spaced axially along the tissue sampling element.

18. The system of claim 13, wherein the transport device is configured for transbronchial insertion.

19. The system of claim 13, wherein the delivery device is configured for percutaneous insertion.

20. The system described in claim 13, wherein the ultrasound transducer is operably coupled to an imaging console configured to display the first radial image and the second radial image.

Images