1. Technical Field
Embodiments of the invention relate generally to the field of medical devices, and in particular, to methods, systems, and devices for navigating to and biopsying tissue such as lung nodules or nodes at a site of interest. In particular, certain embodiments described herein use a flexible needle to biopsy tissue.
2. Description of the Related Art
Early diagnosis of potentially cancerous tissue is an important step in the treatment of cancer because, the sooner that cancerous tissue can be treated, and the better the patient's chances are for survival. Typical diagnostic procedures involve biopsying tissue at a site of interest. In the case of lungs, lung cancer can be difficult to diagnose due to the difficulties in accessing airways near areas of interest. Areas of interest may present as lung nodules—small tissue masses in the lung that may range in size between 5-25 mm—that typically are biopsied to ascertain whether the tissue therein is cancerous or otherwise diseased.
Existing systems typically are constrained by difficulties in accessing lung nodules, especially in the smaller peripheral airways that may be too narrow to accommodate larger catheters and biopsy apparatuses. Further, the biopsy needles normally are straight and relatively inflexible. Thus, the biopsy needles can limit the articulation of a bronchoscope or can be difficult to pass through a working channel of a bronchoscope when the bronchoscope is articulated around a tight corner. In some instances, the material of the needle may inelastically yield, which can result in a bent needle that is difficult to control. In addition, the straight biopsy needles obtain samples along an axis of the needle through back and forth cycling of the needle. Thus, obtaining multiple samples from different regions of a single nodule, for example, can be difficult and can require repeated repositioning of the bronchoscope or guide sheath, for example.
Accordingly, embodiments described herein relate generally to methods, systems, and devices for navigating to and biopsying tissue at a site of interest. In particular, embodiments described herein may be used for biopsying tissue in a lung (such as lung nodules or lymph nodes) using a flexible transbronchial biopsy aspiration needle system. Certain embodiments provide for the flexible biopsy needle to be steerable or guidable to a location of interest. Further embodiments provide for a visualization system (e.g., ultrasound) to be provided in a flexible, miniaturized configuration, and this visualization system may be combined with the flexible biopsy needle.
In one embodiment, a system for obtaining a tissue sample in or near an airway comprises:
a flexible needle with distal and proximal ends, the distal end of the needle comprising a less flexible distal tip region and a more flexible proximal region, the less flexible distal tip region comprising a piercing tip configured to obtain a tissue sample, and the more flexible proximal region configured to bend;
a catheter, wherein the catheter comprises at least one interior lumen, the flexible needle being slidably received within the at least one interior lumen; and
a suction source in fluid communication with the flexible needle.
Additional embodiments comprise a steering mechanism configured to steer the flexible needle toward a site of the tissue to be sampled. The steering mechanism may comprise at least one guidewire extending longitudinally along the exterior of the flexible needle or the at least one interior lumen. In some configurations, the steering mechanism may comprise a guidewire extending within an interior lumen of the flexible needle. In some embodiments, the guidewire is removable from the interior lumen of the flexible needle. The system may also comprise a navigation system. The navigation system can utilize an ultrasound probe. In some embodiments, the ultrasound probe is located at a distal end of the catheter. In some embodiments, the catheter comprises a second lumen and the ultrasound probe is received within the second lumen. In some embodiments, the catheter is received within the working channel of a bronchoscope. Some configurations may provide for the catheter being received within a bronchoscope comprising a second steering mechanism, wherein the second steering mechanism can steer independently of the steering mechanism configured to steer the flexible needle.
In another embodiment, a method for obtaining a tissue sample in or near an airway comprises:
identifying a location in the airway in close proximity to a tissue sample site;
introducing a flexible needle into the airway;
navigating the flexible needle to the location in the airway;
articulating the flexible needle in a direction toward a tissue sample site; and
obtaining a tissue sample from the tissue sample site, wherein the flexible needle pierces into the tissue sample site, and wherein suction is applied to the flexible needle so as to collect tissue from the tissue sample site.
In some embodiments, the flexible needle is articulated by a steering mechanism. In some embodiments, the flexible needle is inserted into a lumen of a catheter. In some embodiments, the step of navigating comprises locating the flexible needle with a radioopaque marker situated on the flexible needle and/or the catheter. In some embodiments, the flexible needle is inserted into a lumen of a bronchoscope.
In some embodiments, a flexible needle configured to access a location near an airway, has a length and comprises a proximal end and a distal end comprising a piercing tip. The needle can include a flexible proximal tip region located along the length of the flexible needle between the distal end and the proximal end, the flexible proximal tip region having one or more flexibility increasing features and configured to bend. In some embodiments, the flexible needle includes a flexible distal tip region located along the length of the flexible needle between the flexible proximal tip region and the distal end, wherein the flexible distal tip region is less flexible than the proximal tip region. The flexibility increasing feature can be, for example, one or more cuts in the flexible needle. In some embodiments, the one or more cuts extend in a spiral fashion along flexible proximal tip region. In some embodiments, the one or more cuts are arranged in a jigsaw configuration. In some embodiments, the one or more cuts are arranged in a serpentine configuration. In some embodiments, the one or more cuts comprise an interrupted spiral pattern where the flexible needle has cut and uncut portions along a same spiral path. In some embodiments, the one or more cuts are distributed asymmetrically on a portion of the length of flexible needle such that the cuts are located on only a portion of a radial circumference of the flexible needle.
According to some embodiments, the flexible needle and any variants thereof can be used in combination with a catheter comprising at least one interior lumen, the flexible needle being slidably received within the at least one interior lumen, and with a suction source in fluid communication with the flexible needle. Such a combination can form a system for accessing tissue near an airway. The system can include a steering mechanism configured to steer the flexible needle toward the tissue sample site. In some embodiments, the steering mechanism comprises at least one guidewire extending longitudinally along the exterior of the flexible needle or the at least one interior lumen. In some embodiments, the steering mechanism comprises a guidewire extending within an interior lumen of the flexible needle. In some embodiments, the guidewire is removable from the interior lumen of the flexible needle. According to some variants, the system includes a navigation system. The navigation system can be an ultrasound probe. The ultrasound probe can be located at a distal end of the catheter. The catheter can include a second lumen and the ultrasound probe is received within the second lumen. In some embodiments, the catheter is received within the working channel of a bronchoscope. In some embodiments, the catheter is received within a bronchoscope comprising a second steering mechanism, and the second steering mechanism can steer independently of the steering mechanism configured to steer the flexible needle.
In some embodiments, a method of manufacturing a flexible needle can include providing a tube shaped length of resilient material having a distal end and a proximal end, forming an angled tip on the distal end of the tube shaped length of resilient material, and forming one or more flexibility increasing features on the tube shaped length of resilient material, such that the flexible needle has a flexible proximal tip region located along the tube shaped length of resilient material between the distal end and the proximal end, the flexible proximal tip region having one or more flexibility increasing features and configured to bend, and such that a flexible distal tip region located along the tube shaped length of resilient material between the flexible proximal tip region and the distal end, wherein the flexible distal tip region is less flexible than the proximal tip region. In some embodiments, forming the one or more flexibility increasing features includes cutting one or more cuts into a wall of the tube shaped length of resilient material. In some embodiments, cutting the one or more cuts includes water jetting the wall of the tube shaped length of resilient material. In some embodiments, cutting the one or more cuts includes laser cutting the wall of the tube shaped length of resilient material. In some embodiments, cutting the one or more cuts includes chemical etching the wall of the tube shaped length of resilient material.
A method for obtaining a tissue sample near an airway can include identifying a location in the airway in close proximity to a tissue sample site, introducing a flexible needle into the airway, navigating the flexible needle to the location in the airway, articulating the flexible needle in a direction toward the tissue sample site, and obtaining a tissue sample from the tissue sample site, wherein the flexible needle pierces the airway and into the tissue sample site, and wherein suction is applied to the flexible needle so as to collect tissue from the tissue sample site. The method can include articulating the flexible needle using a steering mechanism. In some embodiments, the flexible needle is inserted into a lumen of a catheter. In some embodiments, the step of navigating comprises locating the flexible needle with a radioopaque marker situated on the flexible needle and/or the catheter. In some embodiments the flexible needle is inserted into a lumen of a bronchoscope.
Various example embodiments of the disclosure can be described in view of the following clauses:
Clause 1: a flexible needle configured to access a location near an airway, the flexible needle having a length and comprising: a proximal end; a distal end comprising a piercing tip; a flexible proximal tip region located along the length of the flexible needle between the distal end and the proximal end, the flexible proximal tip region having one or more flexibility increasing features and configured to bend; and a flexible distal tip region located along the length of the flexible needle between the flexible proximal tip region and the distal end, wherein the flexible distal tip region is less flexible than the proximal tip region.
Clause 2: the flexible needle of Clause 1, wherein the flexibility increasing feature comprises one or more cuts in the flexible needle.
Clause 3: the flexible needle of Clause 2, wherein the one or more cuts extend in a spiral fashion along flexible proximal tip region.
Clause 4: the flexible needle of Clause 2, wherein the one or more cuts are arranged in a jigsaw configuration.
Clause 5: the flexible needle of Clause 2, wherein the one or more cuts are arranged in a serpentine configuration.
Clause 6: the flexible needle of Clause 2, wherein the one or more cuts are arranged in an interrupted spiral pattern where the flexible needle has cut and uncut portions along a same spiral path.
Clause 7: the flexible needle of and of Clauses 2-6, wherein the one or more cuts are distributed asymmetrically on a portion of the length of flexible needle such that the cuts are located on only a portion of a radial circumference of the flexible needle.
Clause 8: a system for accessing tissue near an airway, the system comprising: the flexible needle of Clause 1; a catheter comprising at least one interior lumen, the flexible needle being slidably received within the at least one interior lumen; and a suction source in fluid communication with the flexible needle.
Clause 9: the system of Clause 8, further comprising a steering mechanism configured to steer the flexible needle toward the tissue sample site.
Clause 10: the system of Clause 9, wherein the steering mechanism comprises at least one guidewire extending longitudinally along the exterior of the flexible needle or the at least one interior lumen.
Clause 11: the system of either of Clauses 9 or 10, wherein the steering mechanism comprises a guidewire extending within an interior lumen of the flexible needle.
Clause 12: the system of Clause 11, wherein the guidewire is removable from the interior lumen of the flexible needle.
Clause 13: the system of any of Clauses 8-12, further comprising a navigation system.
Clause 14: the system of Clause 13, wherein the navigation system is an ultrasound probe.
Clause 15: the system of Clause 14, wherein the ultrasound probe is located at a distal end of the catheter.
Clause 16: the system of Clauses 14 or 15, wherein the catheter comprises a second lumen and the ultrasound probe is received within the second lumen.
Clause 17: the system of any of Clauses 8-16, wherein the catheter is received within the working channel of a bronchoscope.
Clause 18: the system of any of Clauses 9-17, wherein the catheter is received within a bronchoscope comprising a second steering mechanism, and wherein the second steering mechanism can steer independently of the steering mechanism configured to steer the flexible needle.
Clause 19: a method of manufacturing a flexible needle comprising: providing a tube shaped length of resilient material having a distal end and a proximal end; forming an angled tip on the distal end of the tube shaped length of resilient material; forming one or more flexibility increasing features on the tube shaped length of resilient material, such that the flexible needle comprises: a flexible proximal tip region located along the tube shaped length of resilient material between the distal end and the proximal end, the flexible proximal tip region having one or more flexibility increasing features and configured to bend; and a flexible distal tip region located along the tube shaped length of resilient material between the flexible proximal tip region and the distal end, wherein the flexible distal tip region is less flexible than the proximal tip region.
Clause 20: the method of Clause 19, wherein forming the one or more flexibility increasing features includes cutting one or more cuts into a wall of the tube shaped length of resilient material.
Clause 21: the method of Clause 20, wherein cutting the one or more cuts includes water jetting the wall of the tube shaped length of resilient material.
Clause 22: the method of Clause 20, wherein cutting the one or more cuts includes laser cutting the wall of the tube shaped length of resilient material.
Clause 23: the method of Clause 20, wherein cutting the one or more cuts includes chemical etching the wall of the tube shaped length of resilient material.
Clause 24: a method for obtaining a tissue sample near an airway, the method comprising: identifying a location in the airway in close proximity to a tissue sample site; introducing a flexible needle into the airway; navigating the flexible needle to the location in the airway; articulating the flexible needle in a direction toward the tissue sample site; and obtaining a tissue sample from the tissue sample site, wherein the flexible needle pierces the airway and into the tissue sample site, and wherein suction is applied to the flexible needle so as to collect tissue from the tissue sample site.
Clause 25: the method of Clause 24, wherein the flexible needle is articulated by a steering mechanism.
Clause 26: the method of any of Clauses 24 or 25, wherein the flexible needle is inserted into a lumen of a catheter.
Clause 27: the method of Clause 26, wherein the step of navigating comprises locating the flexible needle with a radioopaque marker situated on the flexible needle and/or the catheter.
Clause 28: the method of Clause 24, wherein the flexible needle is inserted into a lumen of a bronchoscope.
The foregoing and other features, aspects and advantages of the present invention are described in detail below with reference to the drawings of various embodiments, which are intended to illustrate and not to limit the invention. The drawings comprise the following figures in which:
Various embodiments of a flexible transbronchial needle aspiration system and its related components and parts will now be described with reference to the accompanying figures. The terminology used in the description presented herein is not intended to be interpreted in any limited or restricted manner. Rather, the terminology is simply being utilized in conjunction with a detailed description of embodiments of the systems, methods and related components. Furthermore, embodiments may comprise several novel features, no single one of which is solely responsible for its desirable attributes or is believed to be essential to practicing the disclosure herein described. For example, while references may be made herein to using the embodiments described herein with terms such as “lung,” “airway,” “nodule,” and so forth, these terms are broad and the embodiments described may be used without limitation and unless otherwise indicated can be used to access to other vessels, passages, lumens, body cavities, tissues, and organs present in humans and animals. For example, lumens such as the gastrointestinal system may be accessed with the embodiments described herein.
Presently, various companies offer products directed to transbronchial needle aspiration systems, some of which include visualization systems to direct the needle to a site to be biopsied. For example, Olympus manufactures an ultrasound system (the Endobronchial Ultrasound Transbronchial Needle Aspiration system (EBUS-TBNA)) substantially as illustrated in
A proximal end of the needle 200 comprises a proximal shaft portion 202. The distal end comprises a flexible shaft portion 204 that is more flexible than the proximal shaft portion and preferably able to selectively bend, curve, and articulate such that the respective ends of the needle 200 are not necessarily collinear. For example, due to the flexible nature of the needle 200, the needle 200 is capable of at least two different deflections in radial directions to angles that would exceed the yield strength of a solid needle formed of the same material. At the extreme distal end, the flexible shaft portion 204 comprises a short distal tip portion 206. This distal tip portion 206 is configured with a piercing tip used to obtain biopsy cell and/or tissue samples. The distal tip portion 206 preferably is more rigid than the flexible shaft portion 204.
In some embodiments, the flexible transbronchial needle 200 can be advanced to peripheral airways and can easily penetrate into the lung parenchyma. In a preferred configuration, the needle 200 can penetrate tissue at a depth of at least 15 mm. In some embodiments, the distal end 204, 206 of the needle 200 can articulate such that it can bend over 90 degrees relative to a more proximal portion. In a preferred embodiment and when inserted into a bronchoscope working channel (such as the BF-P180™ bronchoscope manufactured by Olympus), the needle 200 can articulate at least 130 degrees when the needle tip 206 is flush with the end of the bronchoscope. When inserted into a system 100 similar to that illustrated in
The flexible needle 200 can be formed from any suitable material. In some configurations, the flexible needle 200 may be formed from a metal or metal alloy, such as stainless steel, nitinol or the like. In some arrangements, the flexible needle 200 can comprise a polymer or other suitable covering over at least a portion of the length of the flexible needle 200. In some configurations, the flexible needle 200 can comprise a heat shrink material that covers substantially the entire length of the flexible needle 200. In some configurations, one or more of the inner and outer surfaces can receive a coating of any suitable material. The coating can improve the lubricity of the coated surface or increase the smoothness of the coated surface. In some configurations, the flexible needle 200 is constructed from a hypotube. Preferably, the hypotube is constructed to be relatively smooth along at least a proximal portion such that when introduced into a device such as a catheter lumen, for example but without limitation, the hypotube is able to relatively freely slide, rotate, or otherwise move along the lumen.
Embodiments described herein (for example but without limitation, the embodiment illustrated in
In some embodiments, visualization of the needle 200 may be enhanced (in particular for ultrasound) by including signature markers that will enhance the visibility of the needle 200. Signature markers may include forming dimples, scallops or the like on the needle 200, which dimples, scallops or the like can reflect ultrasound. Of course, other markers visible for different visualization methods can be used, such as radioopaque markers located on various elements of the catheter or sheath used to deploy the needle 200, as well as the needle 200 itself.
Although ultrasound has been found to be a preferable system for visualization due to the relatively high penetration depth (10-18 mm) of ultrasound, other systems also may be used. In some configurations, a spiral ultrasound probe can be used to provide improved visualization over an ultrasound probe that provides visualization in only a single plane. Other systems for locating and navigating to tissues of interest, such as lung nodules and lymph nodes, may include using a bronchoscope with an optical channel, fluoroscopy, optical coherence tomography, and magnetic resonance imaging. Any other suitable navigation systems also can be used, including commercial systems using X-ray computed tomography assisted visualization (such as, for example but without limitation, the BfNavi™ system sold by Olympus and the i-Logic™ system sold by SuperDimension).
The flexibility of the region of increased flexibility 302 may be tailored as desired for a particular application. The flexibility can be changed, for example, by modifying the thickness of the needle wall 300, the materials used therein, and the spacing, pitch, and angle between the flexibility increasing features 304 in the region of increased flexibility 302. Preferably, the cuts 304 extend in a spiral fashion along the region of increased flexibility 302. In preferred embodiments, the features 304 are cut with a thickness between about 0.0010 and about 0.0025 inches, and even more preferably a range between about 0.0015 and about 0.0020 inches.
Additionally, the region of increased flexibility 302 does not need to have features such as the single pitch illustrated in
Embodiments of needle walls 300 with asymmetrical regions of increased flexibility may be useful in conjunction with bronchoscopes or other navigational devices by increasing the maneuverability of the needle wall 300 while in the bronchoscope. In particular, some bronchoscopes may be more adapted to bending in a particular plane—alignment of the asymmetrical region of increased flexibility 302 in this plane may thus be useful. For example, asymmetric bending of the needle wall 300 can force the needle wall 300 to rotate about its longitudinal axis as the navigational device bends and flexes. Such rotation can help to ensure that certain features of the needle could be maintained in a substantially consistent alignment with regard to the navigational device. For example, the bevel of the distal tip of the needle and/or ultrasonic reflective zones of the needle walls 300 could be maintained at a substantially consistent rotational orientation with respect the navigational device (e.g., a bronchoscope). Further, rotation of the needle wall 300 along its axial length may also aid navigation and maneuverability, as certain embodiments with asymmetrical regions of increased flexibility 302 have been demonstrated to rotate in the path of least resistance, typically the smallest possible radius.
The cuts 304 may not necessarily be straight and perpendicular to the longitudinal axis of the needle wall 300. As illustrated in
Several characteristics of the cuts 304 may be altered to tailor the stiffness, bending resistance, torqueability, and other material parameters of the region of increased flexibility 302. For example, the kerf, or cut width, in each cut 304 may be larger at some points than at others, which may enhance flexibility. In some embodiments, the kerf at a midpoint 311 of a cut 304 may be wider than the kerf at one or more of the ends 310. In such a configuration, the flexibility may be increased when the needle wall 300 is bent in the direction or plane of the asymmetrical region of increased flexibility 302, while reducing or minimizing flexibility (progressively or in a stepwise manner) as the bend location moves away from the direction or plane of the region of increased flexibility, as a result of the change in kerf toward the ends 310. It may also be preferable to have a thinner kerf to reduce the amount of torque that can be applied to the needle wall 300 before the tube interlocks. Additionally, the kerf may be modified along the length of the region of increased flexibility 302. For example, the kerf in a proximal section may be wider and taper to a narrower kerf at the distal end, which may provide for a needle wall 300 that is flexible but that will stiffen when rotated.
Other characteristics of the region of increased flexibility 302 may be modified. In addition to the kerf, the pitch spacing, the length and/or amount that a cut 304 extends around the needle wall 300, and the distance between cuts 304 may be modified to tailor the wall 300 as desired. In some embodiments, the minimum longitudinal distance point between the cuts 304 can be varied along the length of the needle wall 302. In some such embodiments, the flexibility of the needle wall 302 can vary along the length of the needle (e.g., more flexibility as the minimal longitudinal distance between the cuts 304 is reduced). Accordingly, the flexibilility, torqueability, and other characteristics of the region of increased flexibility may be modified. Further, some embodiments may provide for a needle wall 300 comprising multiple asymmetrical regions of increased flexibility 302. In some embodiments, the multiple regions 302 may be staggered at differing orientations, for example in mutually orthogonal directions (i.e., at 90° angles to each other).
In practice, in tailoring the region of increased flexibility 302 and the reliefs 304 that can constitute this region of increased flexibility 302, it may be desirable to find a suitable balance between the flexibility required and the type of relief. For example, while wider or larger reliefs may provide additional flexibility, these may in some cases weaken the needle wall 300 to an unacceptable extent. Different patterns also may perform more or less satisfactorily in fatigue testing. Additionally, certain patterns may cause portions of the region of increased flexibility 302 to abrade the working channel of the catheter or other instrument the needle is inserted in, or else the tissue being biopsied (although this may be desirable in certain applications, as described below). Postprocessing after creation of the reliefs may include steps such as deburring, electropolishing, extrude honing, microblasting, or ultrasonic cleaning, which may at least partially alleviate or reduce such concerns. The type of reliefs 304 described above may also be adjusted in accordance with the length of the one or more regions of increased flexibility 302. Prototypes have been constructed with regions of increased flexibility measuring approximately 3-4 cm. Preferably, the extreme distal end of the needle wall 300 is left uncut or otherwise generally solid to reduce the likelihood of buckling and so that a piercing point can be made onto the needle. In some arrangements, the piercing point is ground or honed and the generally solid portion of the extreme distal end assists in the formation of a point or tip. In some embodiments, the generally solid distal region measures between about 8 mm and about 10 mm. Other configurations are possible.
Obtaining a cored tissue sample may be preferable for pathology or histology samples where a largely-intact sample of tissue is desired. For such applications, the needle is preferably in a relatively larger size range of approximately 17-19 gauge, possibly with a smaller 21 gauge needle within. Such needle sizes have been found to produce a “cored” tissue sample satisfactory for histology applications. Obtaining biopsy cells and fluid for cytology may however use a smaller, non- or minimally-coring distal tip portion 402, for example. Because biopsies for cytological applications typically apply suction while performing agitation (moving back and forth) of the needle in the biopsy site, sharper and/or rougher needles may perform better and obtain additional cells. For such applications, smaller needle sizes in the range of 21-23 gauge may also be preferable. In some embodiments, the distal tip portion 402 may be cut and/or angled differently for different applications. In some applications, a hole, port, slot or other structure also can be provided just proximal of the distal end. In some applications, the hole, port, slot or other structure can be provided on a surface of the needle that is opposite from the surface of the needle having the most proximal portion of the beveled opening formed at the tip. In some applications, the hole, port, slot or other structure is positioned within a region defined between the distal tip and the most proximal portion of the opening formed by the beveled surface of the opening at the tip. A vacuum source may also be provided so as to aspirate a tissue sample or samples. Other configurations also are possible.
The cuts 406 on the flexible region 404 may be suitable for cytological biopsy procedures. Here, a cut may provide rougher edges that can scrape cells along the path of the needle 400. For example, when the interrupted surface of the needle is bent, the cuts can create a scalloped surface. In particular, sinusoidal, “jigsaw,” “serpentine,” or zigzag cuts may provide for rougher edges, which—especially when the needle 400 is bent or articulated—can abrade the surrounding tissue and thus sample additional cells. These abraded cells can then be aspirated via the needle 400 along with any other sample being biopsied. If no coating and/or heat shrink wrap 408 is present over the cuts 406, the resulting small openings may also be used to aspirate the abraded cells into the needle 400. Such an uncoated portion of the cut section 406, if present, is preferably located at the distal end of the needle 400 such that surrounding tissue may ingress into the inner lumen during suction.
To increase this scraping or scalloping effect, several steps may be taken. If the cuts 406 are made by water jetting, the needle 400 may be extrude honed to push burrs outward, increasing the roughness of the flexible region 404. Likewise, laser cutting the cuts 406 may in some cases provide additional roughness. In some cases, a polishing or deburring step may be necessary. Dimpling or grinding of the cuts 406 and/or the region 404 may also be useful. The kerf (or width) of the cuts 406 may also be increased, either in part or in whole, along the flexible region 404, which may consequently enhance the scraping or scalloping effect.
The needle 400 may also be flushed after being withdrawn so as to obtain any remaining cells. In some cases, the operator using a needle 400 with cuts 406 will preferably navigate the needle 400 so as to reduce the likelihood of abrading or puncturing blood vessels in the biopsy region, because the resulting jagged edges may take longer to stop bleeding than a cut resulting from a biopsy needle lacking cuts. In some configurations, a dual-needle configuration, with a relatively smooth needle used to puncture into the biopsy site, followed by larger diameter, flexible needle that can include scalloped surfaces that can be used to scrape the tissue. Quick-clotting or cauterizing features could also be incorporated into the needle 400 or various other system components to minimize bleeding when piercing tissue.
This embodiment of a flexible transbronchial needle 500 has several advantages, as on one hand the needle 500 becomes more torquable and pushable while also retaining flexibility at its distal end. The less flexible shaft portion 502 at the proximal end is preferably more rigid and stiffer than the more flexible shaft portion 504, so as to facilitate torque and force transmission to the thinner, more flexible shaft portion 504. In one embodiment, this is accomplished by constructing the needle 500 so as to become progressively thinner from the proximal end to the distal end, such that the flexible shaft portion 504 remains flexible and bendable. By constructing the needle 500 in a manner that it becomes thinner at the tapered shaft portion 524, the needle becomes more flexible, while also reducing resistance to rotation in the distal end comprising the flexible shaft portion 504. Additionally, the more rigid portion 502 is more durable and better able to transmit torque or force, while being situated in a portion of the needle 500 where flexibility is less important.
The less flexible shaft portion 502 has an outside diameter D1 514. The more flexible shaft portion 504 has an outside diameter D2 516. The tapered shaft section 524 has a proximal end 518 and a distal end 520, with the outside diameter D3 522 being located at the proximal end of the tapered shaft section 518 and the outside diameter D4 520 being located at the distal end of the tapered shaft section 520. Preferably, the outside diameter D3 522 is equal to the outside diameter D1 514. The outside diameter D4 520 is preferably equal to the outside diameter D2 516. The outside diameter of the tapered section 524 may vary linearly or nonlinearly between D3 and D4. It will also be understood that in some embodiments, the tapered section 524 may extend into all or part of the flexible shaft portion 504 and/or the less flexible shaft portion 502, and that in some embodiments there may be additional tapered sections. Further, although the tapered section 524 reduces in diameter going in a proximal to distal direction, the opposite configuration may be useful in some embodiments.
Typically, the portions 502, 524, 504 will be constructed from a length of material (e.g., metals such as stainless steel or nitinol) of a substantially uniform thickness, and as such, the inside diameters of the respective portions will generally correlate to the outside diameters referred to above. However, it is contemplated that materials of varying thicknesses may be used to construct the needle, and the thickness defined by the inside and outside diameters may differ along the length of the device. This may be accomplished, for example, by constructing the needle 500 in a piecewise fashion from separate parts, or by drawing out the needle in a single unit so as to create sections of varying thickness. Such varying thicknesses may be used, for example, to tailor factors such as the rigidity, strength, torquability, or flexibility of the resulting needle to the desired application.
In
In these preceding figures, the steering wires may be manipulated by the operator to guide a flexible transbronchial needle to a site of interest. Preferably, this is accomplished by using the one or more steering wires to pull (and thereby bend) the flexible needle in the direction desired. The wires may be attached to the flexible needle in any suitable manner, on the interior or exterior of the flexible needle. In some configurations, the wires are secured by welding them to the flexible needle. When wires are attached to the interior of the flexible needle, such embodiments may allow for insertion into a smaller sheath or working channel. In certain embodiments, this may be accomplished by having the steering wire comprise one or more pull wires. Bowden cables may be used in some embodiments. Nitinol wires, which contract after being heated past a transition temperature may also be used, possibly in conjunction with a heating element controllable by the operator (for example, by using resistive heating).
In some embodiments, a steering wire 708 is located along the exterior of the flexible shaft portion 702. In other embodiments, multiple steering wires 708 are located along the exterior of the flexible shaft portion 702; these may be arranged as depicted above in
The proximal end of the needle 700 may be part of or joined to a steel hypotube 711. The proximal end of the hypotube 711 may also have a connection 714 (for example, a luer fitting) so that a source of vacuum (for example, a pump or syringe 712) can be used to pull a vacuum along the length of the hypotube 711. In a preferred embodiment, the hypotube 711 is manufactured from any suitable material.
The needle 800 preferably comprises a distal tip portion 802 with a distal opening 803. A flexible section 804 preferably is configured to be more flexible than the distal tip portion, and may comprise cuts 806 of the type previously described. These cuts 806 confer additional flexibility to the needle 800 and permit it to bend or curve. In some embodiments, all or part of the flexible section 804 (and the cuts 806) may be covered with a coating 808, which may be a polymer and/or heat shrink, for example but without limitation.
The guidewire 810 preferably is constructed from a shape memory material (metal or polymer) such as Nitinol. Preferably, the guidewire 810 is set in a form that will curve when heated, but is inserted into the needle 800 while in a straightened configuration. While the guidewire 810 is inserted into the needle 800, heating of the guidewire 810 will cause it to curve, thereby curving the needle 800 along its flexible section 804. In some configurations, the guidewire 810 simply is inelastically deformed to provide non-linear region proximate the distal end. In such configurations, simply inserting the guidewire 810 into the needle 800 can cause the needle to bend.
In use, the curved guidewire 810 can be used to steer the needle 810 by rotating the guidewire 810 relative to the needle 810. The curve or bend in the guidewire 810 will cause the flexible portion of the needle 810 to deflect such that the direction of the needle 810 can be varied. In some embodiments, rotational alignment of the curved guide wire 810 with respect to the needle 800 can be controlled using an asymmetric distribution of cuts on the needle wall (e.g., as described above with regard to
In certain embodiments, the curved guidewire 810 may be part of a system used for providing repeatable access and/or navigation to regions of the lung. Such embodiments are described in Provisional Application Ser. No. 61/604,462, filed Feb. 28, 2012, titled “PULMONARY NODULE ACCESS DEVICES AND METHODS OF USING THE SAME”, and the application is hereby incorporated by reference in its entirety. Such embodiments are also described in U.S. patent application Ser. No. ______ (Attorney Docket No. SPIRTN.082A), filed Feb. 26, 2013, titled “PULMONARY NODULE ACCESS DEVICES AND METHODS OF USING THE SAME” and published as U.S. Patent Publication No. ______, and the publication is hereby incorporated by reference in its entirety.
A method of obtaining a tissue sample may comprise advancing the bronchoscope 1014 toward a tissue site (e.g., a lung nodule 1012 or lymph node). Within the bronchoscope 1014, the catheter 1000 may be movably disposed. In some embodiments, and preferably when advancing to tissue regions in small or convoluted airways that may not permit navigation with the bronchoscope 1014, a guide sheath surrounding the catheter 1000 may be advanced beyond the bronchoscope 1014 instead of or in conjunction with the guidewire 1008. In some embodiments, the guide sheath may be used without the bronchoscope 1014. The guide sheath may be used in conjunction with a location device, such as fiducial markers (e.g., coils 1004) or an ultrasound probe (e.g., as described below in
The catheter 1100 also preferably comprises at least one steering wire 1106, which preferably is connected to the second lumen 1104 to permit selective articulation and bending of the distal end of the second lumen 1104. The steering wire 1100 is preferably of the type that may be used in the embodiments described above in
Articulating the distal end of the second lumen 1104 of the catheter 1100 allows tools, in this case distal end of the needle 1114, to be angled toward the target nodule 1112 while the ultrasound probe 1116 remains in the airway providing real-time location confirmation that the needle 1114 has reached the target nodule 1112. Accordingly, the angle of the second lumen 604 preferably is adjusted and aligned such that the needle 1114 and nodule 1112 simultaneously remain in the field of view 1118 of the ultrasound probe 1116. Embodiments of the catheter 1100 have been constructed wherein the needle 1114 is able to articulate up to 20 degrees relative to the ultrasound probe. Some embodiments have been constructed that are compatible with a 3.2 mm bronchoscope working channel, and may be miniaturized further.
It will be understood that the present descriptions of the lung biopsy systems, apparatuses, and methods described herein as being used in a lung and for lung nodules are not limiting, and that these embodiments may be used for biopsying, navigating, and locating areas of interest in other locations on a patient, including gastric, endoscopic, or other suitable locations. Similarly, a bronchoscope is not necessary, and other suitable devices capable of accommodating the embodiments described herein may also be used, including without limitation various endoscopes or laparoscopic cannulas.
Although this invention has been disclosed in the context of certain embodiments and examples, those skilled in the art will understand that the present invention extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses of the invention and obvious modifications and equivalents thereof. In addition, while several variations of the invention have been shown and described in detail, other modifications, which are within the scope of this invention, will be readily apparent to those of skill in the art based upon this disclosure. It is also contemplated that various combinations or sub-combinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the invention. It should be understood that various features and aspects of the disclosed embodiments can be combined with, or substituted for, one another in order to form varying modes or embodiments of the disclosed invention. Thus, it is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above.
Any and all priority claims identified in the Application Data Sheet, or any correction thereto, are hereby incorporated by reference under 37 CFR 1.57.
Number | Date | Country | |
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61604457 | Feb 2012 | US |