Method for removing a tissue lesion

Abstract

A method for removing a tissue lesion where an anchor is established with the lesion. A channel is created in the tissue leading to the anchored lesion. A tissue core is created which includes the lesion. The tissue core is ligated, amputated and removed from the channel.

Claims

1. A method for removing a tissue lesion comprising blood vessels and airways, the method comprising: inserting an anchor through a center portion of the tissue lesion such that a distal end portion of the anchor is positioned at a bottom portion of the tissue lesion; creating a channel in tissue leading to the tissue lesion; creating a tissue core including the tissue lesion; ligating the tissue core at a ligation point downstream from the tissue lesion; amputating the tissue core form the tissue between the ligation point and the tissue lesion; providing a removal device over the anchor such that the tissue lesion is positioned within an inner diameter of the removal device; and removing the tissue core from the channel, the tissue core including sealed vessels and tissue.

2. The method of claim 1, further comprising inserting a sleeve in the channel prior to or after removing the tissue core.

3. The method of claim 2, further comprising anchoring the sleeve to the tissue.

4. The method of claim 2, further comprising delivering localized treatment through the sleeve.

5. The method of claim 1, wherein creating the tissue core includes cauterizing and cutting the tissue.

6. The method of claim 5, wherein ligating the tissue core includes cauterizing the tissue at the ligation point.

7. The method of claim 5, wherein ligating the tissue core includes suturing the tissue at the ligation point.

8. The method of claim 1, wherein amputating the tissue core includes slicing the tissue core.

9. The method of claim 8, wherein amputating the tissue core includes slicing the tissue core with a snare.

10. The method of claim 8, wherein amputating the tissue core includes slicing the tissue core with an energized wire.

11. The method of claim 1, wherein creating the tissue core includes first sealing blood vessels then slicing the tissue to form the tissue core.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing and other features and advantages of the invention will be apparent from the following, more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings.

(2) FIG. 1 depicts a tissue resection device in accordance with an embodiment of the invention.

(3) FIG. 2 illustrates a sectional view of the tissue resection device of FIG. 1.

(4) FIG. 3 shows a sectional view of a tissue resection device in accordance with an embodiment of the invention.

(5) FIG. 4 depicts a sectional view of a tissue resection device in accordance with an embodiment of the invention.

(6) FIG. 5 illustrates an exemplary anchor that may be employed in a lesion removal method in accordance with an embodiment of the invention.

(7) FIG. 6 shows a series of incision blades for use in a lesion removal method in accordance with an embodiment of the invention.

(8) FIG. 7 displays tissue dilators suitable for use in a lesion removal method in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(9) The resection device of the present invention comprises an energy-based arrangement capable of penetrating tissue towards a target lesion. In one embodiment depicted in FIG. 1, tissue resection device 1100 includes an outer tube 1105 is provided having a distal edge profile and having an inner diameter ID.sub.outer. A coil 1110 is attached to outer tube 1105 where the coil turns are spaced from and opposed to a distal end of outer tube 1105. Coil 1110 preferably has a slightly blunted tip 1115 to minimize the possibility that it will penetrate through a blood vessel while being sufficiently sharp to penetrate tissue such as pleura and parenchyma. In some embodiments, coil 1110 may take the form of a helix having a constant or variable pitch. Coil 1110 may also have a variable cross-sectional geometry. An electrode 1130 is disposed on a surface or embedded within coil 1110.

(10) In some embodiments, as illustrated in FIG. 1, coil 1110 may include a plurality of contiguous coil segments, e.g., coil segments 1120 and 1125. Coil segment 1120 comprises a helical member having a pitch of zero, e.g., a generally planar open ring structure, having an inner diameter ID.sub.coil and an outer diameter OD.sub.coil. Coil segment 1125 comprises a helical structure of constant or variable pitch and constant or variable cross-sectional geometry. In this embodiment, electrode 1130 may be disposed on a surface of or embedded in coil segment 1120.

(11) A central tube 1200 is provided having a distal end with an edge profile comprising one or more surface segments and having an outer diameter OD.sub.central and an inner diameter ID.sub.central. As illustrated in FIG. 2, an electrode 1205 is disposed on or embedded within at least one of the surface segments. Central tube 1200 is slidably disposed within outer tube 1105 and positioned such that electrode 1205 opposes and overlaps at least a portion of electrode 1130. The space between electrode 1205 and electrode 1130 is referred to as the tissue clamping zone. In keeping with an aspect of the invention, OD.sub.central>OD.sub.coil and OD.sub.coil>ID.sub.central. In some embodiments, OD.sub.central is about equal to OD.sub.coil. Accordingly, Central tube 1200 may be advanced through the tissue clamping zone towards coil 1110 such that electrode 1205 abuts electrode 1130.

(12) A cutting tube 1300 is slidably disposed within central tube 1200. The distal end of cutting tube 1300 is provided with a knife edge to facilitate tissue cutting.

(13) To enable tissue resection, the resection device 1100 may be inserted into tissue and outer tube 1105 may be advanced a predetermined distance towards a target. Coil segment 1125 allows the device to penetrate the tissue in a manner similar to a cork screw. As coil segment 1125 penetrates tissue, any vessel in its path is either moved to planar coil segment 1120 or pushed away from the coil 1100 for subsequent turns. Coil tip 1115 is made blunt enough to minimize chances that it will penetrate through a blood vessel while still sharp enough to penetrate certain tissue such as the lung pleura and parenchyma. Central tube 1200 may then be advanced a predetermined distance towards the target. Any vessels that are disposed in the tissue clamping zone will be clamped between electrode 1130 and electrode 1205. The vessels can then be sealed by the application of bipolar energy to electrode 1130 and electrode 1205. Once blood vessels are sealed, cutting tube 1300 is advanced to core the tissue to the depth that outer tube 1105 has reached. The sealing and cutting process can be repeated to create a core of desired size.

(14) In keeping with an aspect of the invention, the resection device may be further configured to dissect a target lesion and seal tissue proximate the dissection point. To facilitate dissection and sealing, as illustrated in FIG. 3, central tube 1200 is provided with a ligation snare 1230, first and second ligation electrodes 1215 and 1220, an amputation snare 1225 and a ligation snare 1230. As used herein, the word “snare” refers to a flexible line, e.g., a string or a wire. The inner wall surface of central tube 1200 includes upper and lower circumferential grooved pathways 1212 and 1214 disposed proximate the distal end. The first and second ligation electrodes 1215 and 1220 are disposed on the inner wall of central tube 1200 such that lower circumferential groove 1214 is between them. Upper grooved pathway 1212 is disposed axially above ligation electrodes 1215 and 1220.

(15) Ligation snare 1230 is disposed in lower circumferential groove 1214 and extends through central tube 1200 and axially along the outer wall surface to a snare activation mechanism (not shown). Amputation snare 1225 is disposed in upper circumferential groove 1212 and extends through central tube 1200 and axially along the outer wall surface to a snare activation mechanism (not shown). The outer surface of central tube 1200 may be provided with a plurality of axially extending grooved pathways which receive amputation snare 1225, ligation snare 1230 and are in communication with upper and lower circumferential grooved pathways 1212 and 1214. In addition, electrode leads for ligation electrodes 1215 and 1220 may extend to an energy source via the axially extending grooved pathways.

(16) In operation, the resection device of this embodiment can detach and seal the tissue core. Cutting tube 1300 may be retracted to expose ligation snare 1230 which is preferably made of flexible line, e.g., suture. Ligation snare 1230 may be engaged to snag tissue and pull tissue against the inner wall surface between first and second ligation electrodes 1215 and 1220. Bipolar energy is then applied to first and second electrodes 1215 and 1220 to seal, i.e., cauterize, the tissue. Once sealed, cutting tube 1300 may be further retracted to expose amputation snare 1225 which may then be activated to sever the tissue core upstream from the point where the tissue was sealed (ligation point). In some embodiments, amputation snare 1225 has a smaller diameter than that of ligation snare 1230. The smaller diameter facilitates tissue slicing. Accordingly, the resection device 1100 according to this embodiment both creates a tissue core and disengages the core from surrounding tissue.

(17) In an alternative embodiment, the resection device of the invention is provided with a single snare disposed between ligation electrodes which both ligates and cuts tissue. In this embodiment, the single snare first pulls tissue against the inner wall surface of central tube 1200 between ligation electrodes 1215 and 1220. Bipolar energy is then applied to first and second electrodes 1215 and 1220 to seal, i.e., cauterize, the tissue. Once sealed, the snare is further pulled to sever the tissue core.

(18) In yet another embodiment, cutting and sealing may be performed without employing electrodes. In this embodiment, ligation snare 1230 includes a set of knots 1235 and 1240 which tighten under load, shown, for example, in FIG. 4. Ligation is performed by retracting cutting tube 1300 to expose ligation snare 1210 and activating ligation snare 1230 which lassos tissue as ligation knot tightens. Once the tissue is lassoed, cutting tube 1300 may be further retracted to expose amputation snare 1225 which may then be activated to sever the tissue core upstream from the point where the point where the tissue was lassoed.

(19) The present invention also contemplates a method and system for using the resection device to remove tissue lesions, for example, lung lesions. The method generally comprises anchoring the lesion targeted for removal, creating a channel in the tissue leading to the target lesion, creating a tissue core which includes the anchored lesion, ligating the tissue core and sealing the surrounding tissue, and removing the tissue core including the target lesion from the channel.

(20) Anchoring may be performed by, any suitable structure for securing the device to the lung. Once the lesion is anchored, a channel may be created to facilitate insertion of resection device 1100. The channel may be created by making an incision in the lung area and inserting a tissue dilator and port into the incision. A tissue core which includes the anchored lesion may be created. In keeping with the invention, resection device 1100 may be inserted into the channel and used to create the tissue core, to ligate the tissue core and to seal the tissue core and sever it from the surrounding tissue as described hereinabove. The tissue core may then be removed from the channel. In keeping with the invention, a cavity port may be inserted in the channel to facilitate subsequent treatment of the target lesion site through chemotherapy and/or energy-based tumor extirpation such as radiation.

(21) The anchor depicted in FIG. 5 is suitable for use in performing the method for removing tissue lesions described herein. The anchor comprises an outer tube 1422 having a sufficiently sharp edge to pierce the chest cavity tissue and lung without causing excess damage and an inner tube 1424 disposed within outer tube 1422. One or more tines or fingers 1426 formed from shape memory material, e.g., Nitinol, preformed are attached to the end of inner tube 1424. Outer tube 1422 is retractably disposed over inner tube 1424 such that when outer tube 1422 is retracted, tines 1426 assume their preform shape as shown. In keeping with the invention, outer tube 1422 is retracted after it has pierced the lung lesion thereby causing tines 1426 to engage the lung lesion. Other suitable anchors may include coils and suction-based structures.

(22) The incision blades depicted in FIG. 6 are suitable for use in performing the method for removing tissue lesions described herein. Once anchor 1400 is set, it is preferable to create a small cut or incision to facilitate insertion of chest wall tissue dilator. Incision blades 1605 are used to make a wider cut. Successive incision blades 1605 include a central aperture which allows them to be coaxially advanced along the anchor needle 1405 to create a wider cut in the chest wall, with each successive blade being larger than the previous blade, thereby increasing the width of the incision.

(23) The tissue dilator depicted in FIG. 7 is suitable for use in performing the method for removing tissue lesions described herein. The tissue dilator may comprise any suitable device for creating a channel in organic tissue. In one exemplary embodiment, the tissue dilator assembly includes a single cylindrical rod with rounded end 1510 or a cylindrical rod with rounded end and a rigid sleeve arrangement 1515. Successive tissue dilators are coaxially advanced along the anchor needle to create tissue tract or channel in the chest wall, with each successive dilator being larger than the previous dilator, thereby increasing the diameter of the channel. Once the final dilator with rigid sleeve is deployed, the inner rod 1505 is removed while leaving the rigid sleeve in the intercoastal space between ribs to create direct passage to the lung pleura.

(24) Any tissue resection device capable of penetrating lung tissue and creating a tissue core including a target lesion is suitable for use in performing the method for removing tissue lesions described herein. Tissue resection device 1100 described hereinbefore is preferred.

(25) Once tissue resection device 1100 is removed, a small channel in the lung exits where the target lesion was removed. This channel may be utilized to introduce an energy-based ablation device and/or localized chemotherapy depending on the results of the tissue diagnosis. Accordingly, the method and system of the present invention may not only be utilized to ensure an effective biopsy is performed but also complete removal of the lesion with minimal healthy lung tissue removal.

(26) Although shown and described is what is believed to be the most practical and preferred embodiments, it is apparent that departures from specific designs and methods described and shown will suggest themselves to those skilled in the art and may be used without departing from the spirit and scope of the invention. For example, the systems, devices and methods described herein for removal of lesions from the lung. It will be appreciated by the skilled artisan that the devices and methods described herein may are not limited to the lung and could be used for tissue resection and lesion removal in other areas of the body. The present invention is not restricted to the particular constructions described and illustrated, but should be constructed to cohere with all modifications that may fall within the scope of the appended claims.