WO2015003982A2

WO2015003982A2 - Methods and devices for endoscopic removal of large pedunculated colonic polyps

Info

Publication number: WO2015003982A2
Application number: PCT/EP2014/064126
Authority: WO
Inventors: Eugene Skelton; Ronan BENSON; Anthony Wright; James Hardwick
Original assignee: Movement Industrial Design Limited
Priority date: 2013-07-09
Filing date: 2014-07-02
Publication date: 2015-01-15
Also published as: WO2015003982A3; WO2015003982A4

Abstract

The present invention generally provides treatment devices for ligating and resecting biological tissue, in particular, ligating and resecting internal biological tissue while being used in conjunction with a flexible endoscope, and methods for use thereof. The aim being to maintain haemostasis and subsequently allow for the delivery of electrical current to said biological tissue.

Description

METHODS AND DEVICES FOR ENDOSCOPIC REMOVAL OF LARGE

PEDUNCULATED COLONIC POLYPS

CROSS REFERENCE TO RELATED APPLICATIONS

[0001 ] This application claims priority to and benefit of provisional application USSN 61/844,082 filed on July 9, 2013; the contents of which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

[0002] This application relates generally to surgical procedures and, more particularly, to methods and devices for the endoscopic removal of large pedunculated colonic polyps.

BACKGROUND

[0003 ] A colonic polyp is a polyp (fleshy growth) occurring on the lining of the colon or rectum. If left untreated, colonic polyps can frequently become cancerous. Each year in Europe over 400,000 persons are newly diagnosed with colorectal cancer and this figure is growing every year with a similar trend observed worldwide.

Pedunculated polyps are polyps that are attached to the mucosal wall via a stalk which varies in length and width.

[0004] The most common treatment for colonic polyps is complete removal (polypectomy) using flexible endoscopy via resection with an electrocautery snare, or in the case of small polyps, with hot biopsy forceps. The resection of large pedunculated colonic polyps poses a particular challenge, as these polyps have thick stalks which provide the polyp head with a vascular supply. Before these large polyp stalks can be resected, bleeding prevention measures need to be taken.

[0005] The importance of bleeding prevention is paramount, the majority of patients presenting with large pedunculated colonic polyps will be over 55 years old and possibly on anti-coagulant drugs, so any bleed that gets out of control in the colon will be difficult to stop and could prove fatal. There are currently three common methods of bleeding prevention, discussed in more detail below, but each of these methods have inherent problems when dealing with large pedunculated colonic polyps.

[0006] Ligating loops are designed to snare the polyp by going over the polyp head and then ligate the polyp stalk via strangulation. This technique minimises the risk of bleeding during a polypectomy procedure and helps eliminate the risk of delayed bleeding after the procedure. Large loops allow for the ligation of large polyp stalks. However, this technique is less than ideal for several reasons. The loops can prove difficult to place for the endoscopist, they tend to snag on uneven polyp heads and most loops do not have the structural integrity to fully open in tight spaces. Once a loop is in place, the endoscopist then needs to go over the polyp head once again with an electrocautery snare, if a polyp head is particularly large or awkward this can be very difficult and it is not ideal to have to do this twice. Users also have to be careful to resect above the ligation loop, but below the polyp head, this can be tricky and can sometimes lead to users transecting the ligation loop. There is also a tendency for endoscopists to accidentally over-tighten the ligation loops which can result in unwanted cold resection. However, ligation loops do provide the lowest risk of bleeding.

[0007] Endoscopic clipping is designed to be a simple and reliable technique for achieving haemostasis. it involves mechanically binding and compressing blood vessels in and around the polyp stalk using small metal clips, minimizing the risk of bleeding while providing instant visual feedback to confirm placement. These devices are considered easier to place, however for larger stalks, multiple clips will be required and incomplete strangulation is common. This technique has proven to be less effective than loop ligation in preventing bleeding.

[0008] Endoscopic epinephrine injection is a common method of bleeding prevention which works by temporarily constricting the blood vessels in and around the polyp utilising the properties of the drug epinephrine which is injected directly into and around the polyp stalk. This technique is considered very easy to execute for the user but comes with the highest risk of bleeding and lacks the permanence and reliability of using a mechanical solution. [0009] Accordingly, there is a need for methods and devices for removing a large pedunculated colonic polyp while providing satisfactory bleeding prevention measures. The resulting benefits of such a solution would be lessened or zero post polypectomy bleeding complications, less need to stop anticoagulants with resulting health benefits to the patient and a greater chance of a complete polypectomy.

DESCRIPTION OF THE INVENTION

[0010] The present invention generally provides treatment devices for ligating and resecting biological tissue, in particular, ligating and resecting internal biological tissue while being used in conjunction with a flexible endoscope, and methods for use thereof. The aim being to maintain haemostasis and subsequently allow for the delivery of electrical current to said biological tissue. However, this invention is not limited to being used with a flexible endoscope and variations of this invention could be utilized in many surgical fields including laparoscopic surgery and open surgery and could be used to ligate and resect many types of biological tissue in many areas of the anatomy both internal and external.

[001 1 ] Embodiments of the present invention are aimed at the ligation and resection of large pedunculated colonic polyps and are specifically designed to address the challenges of ligating and resecting said anatomical structures. The present invention has a dual purpose, the first being to ligate and strangulate the stalk of a pedunculated polyp in order to maintain haemostasis. The second being to allow the passing of electrical current into the strangulated polyp stalk with the purpose of resecting said polyp while coagulating the severed tissue to prevent blood flow. This results in polyp removal with minimal blood loss.

[0012] FIGS. 1 , 2, and 4 illustrate an embodiment of a device for ligation and resection of large pedunculated colonic polyps that includes a controlling handle (1), a long flexible cylindrical shaft member (2) and an end effector assembly (3).

[0013] As shown in FIG. 1 , the controlling handle ( 1 ) includes a rigid non-moving shaft member (8), onto which a movable member (9) can be controlled to move back and forth along the rigid non-moving shaft member (8). This movable member (9) is directly linked to the resecting snare member (5) and allows the user to push and pull the resecting snare member from the controlling handle. The resecting snare member functions in a similar manner to a traditional electrocautery snare of which the functionality is clearly known to those skilled the art.

[0014] FIG. 2 shows an exploded view of the end effector assembly. The end effector assembly features an open ended flexible ligating member (4) with interlocking receivers (12), a metal resecting snare member (5) with interlocking protrusions ( 1 1 ) and an opposing protruded retaining member (6).

[0015] FIG 3 shows a cross section view of the snare member and the ligating member and illustrates the embedding of the rigid snare member (5) into the flexible ligating member (4), via an open cross sectional slot ( 10) in the external surface of the flexible ligating member (4). During the initial stages of use, including being passed over the polyp head, the two members act and are controlled as if they were a single member. The resecting snare member (5) can be pulled from the controlling handle which has the effect of pulling the flexible ligating member (4) also. As shown in FIG. 4, functionality can be optimised through the use of protrusions (1 1 ) on the snare member (5) interlocking with receivers (12) on the ligating member (4). The flexible ligating member, which would otherwise have very little structural integrity and be difficult to control, is embodied with the rigid properties of the resecting snare member, making both members easy to control, maneuver and pass over the polyp head, even in tight, constricted spaces.

[0016] FIG. 5 illustrates the flexible ligating member in use. Once both members have been positioned over the head of the polyp ( 13), ligation of the non-constricted polyp stalk ( 14) can take place. This is achieved by retracting the resecting snare member by pulling back the movable member (9) on the controlling handle (1), this reduces the size of the snare capture area ( 15) which captures and constricts the polyp stalk (53). The user continues retracting until visible blanching of the tissue has occurred, as shown in FIG. 6. The increased surface area and flexible nature of the ligating member means that the trauma to the tissue is reduced and unwanted effects such as cold resection are avoided.

[0017] As the resecting snare member and ligating member are pulled inside the cylindrical shaft member, the ligation is made tighter on the polyp stalk causing ligation and strangulation. As shown in FIG. 7, the tightening of the ligating member is irreversible as the cross sectional geometry (16) of the opposing protruded retaining member (6) engages and matches with the cross sectional geometry (17) of the ligating member (4), in effect, the opposing protruded retaining member (6) counteracts the tensile force acting on the ligating member (4) and keeps the ligating member in its constricted form and the tissue in a state of ligation. This functionality is optimised by the inclusion of opposing interlocking surface features (18) which directly counteract the tensile force attempting to pull the two ends of the ligating member apart. The opposing protruded retaining member (6) is prevented from being pulled inside the cylindrical shaft member (2) as its height is greater to or equal to the outer diameter of the cylindrical shaft member.

[001 8] As shown in FIG. 8, when the user is satisfied ligation has been performed adequately, the user pushes the snare member forward, this will push the opposing protruded retaining member and ligating member out of the cylindrical shaft member leaving both components in place ligating the polyp stalk. The user can now push and pull the rigid resecting member to free it completely from the open slot in the flexible ligating member and decouple the ligating member and the opposing protruded retaining member from the system completely. The snare member can now be repositioned higher on the polyp stalk but beneath the polyp head in preparation for the resecting task.

[0019] The user can now attach an electrical power source to the controlling handle and perform the task of resecting the polyp stalk using electrocautery in the traditional methods which are clearly known to those skilled in the art.

[0020] FIG. 9 illustrates an embodiment relating to a method of embodying the flexible ligating member with the structural integrity and controllability of the rigid snare member. This second embodiment involves modifying the ligating member cross section so the open slot ( 10) is no longer present and the ligating member (49) has an elongated cross section with structural rib features (57) along the top and bottom, this cross sectional configuration will maximize the surface area in contact with the polyp stalk, therefore lessening trauma with the aim of preventing cold resection. The cross sectional structural rib features (57) will have a corrugating effect on the ligation member giving this flexible element more strength and rigidity. [0021] As shown in FIG. 10, with the open slot (10) not present in this embodiment a method needs to be in place whereby the controllability of the snare member is transferred to the ligating member also. This is achieved by having 3 coupling points (48) where the snare member passes through slots (47) in the ligating member. The slots are engineered so their cross sectional height is less than or equal to the cross sectional height of the snare member and therefore a friction fit bond is formed. This friction fit bond will be strong enough to allow the snare member and ligating member to be maneuvered and controlled as one member but will also allow for the snare member to be released from the friction fit bonds after ligation of the polyp stalk has taken place.

[0022 ] This invention is not limited to having 3 friction fit coupling points and could have any number of friction fit coupling points including 1, 2, 3, 4, 5, 6 or 7 coupling points.

[0023] FIG. 1 1 illustrates an embodiment relating to a configuration for the snare member (55) and ligating member (56), in this embodiment rather than having the snare member embedded into the ligating member, the two members are orientated in a linear fashion, one after the other, in an end to end configuration, with the ligating member in the distal position closest to the polyp and the snare member in the proximal position closest to the controlling handle.

[0024] As shown in FIG. 12, the snare member can be directly linked to the movable member on the controlling handle, the ligating member (55) has two sections of material removed which form a pullback slot (50), into which the distal end loop (52) of the snare member (55) is positioned and allows the ligating member (56) to be pulled back as the snare member (55) is pulled back, this functionality is used to carry out the task of ligating the polyp. The ligating member is held in a constricted state using a variation of the opposing protruded retaining member (51) as described in the core embodiment. Once the polyp is ligated the snare is pushed forward out of the cylindrical shaft member (2), once the snare member (55) and ligating member (56) are fully outside of the cylindrical shaft member (2) the snare member (55) is free to decouple from the pullback slot (50) in the ligating member (56). The ligating member (56) is then left in position maintaining the polyp stalk in a ligated state, the task of resecting the polyp stalk can now be carried out with the snare member using traditional electrocautery methods which are clearly known to those skilled the art.

[0025] FIG. 13 shows an embodiment of the cross sectional geometry of the ligating member (19) with corresponding cross sectional geometry for the opposing protruded retaining member (20) featuring opposing interlocking surface features (21 ). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (20) from being pulled inside the cylindrical shaft member (2).

[0026] FIG. 14 illustrates an embodiment of the cross sectional geometry of the ligating member (24) with corresponding cross sectional geometry for the opposing protruded retaining member (25) featuring opposing interlocking surface features (21 ). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (25) from being pulled inside the cylindrical shaft member (2).

[0027] FIG. 15 shows an embodiment of the cross sectional geometry of the ligating member (26) with corresponding cross sectional geometry for the opposing protruded retaining member (27) which in this embodiment is two separate components featuring opposing interlocking surface features (21 ). This embodiment also features a cylindrical end piece member (28) with ingress preventing geometry (54). The ingress preventing geometry prevents the opposing protruded retaining member components (27) from being pulled inside the cylindrical shaft member (2).

[0028] FIG. 16 shows an embodiment of the cross sectional geometry of the ligating member (29) with corresponding cross sectional geometry for the opposing protruded retaining member (30) which in this embodiment is two separate components featuring opposing interlocking surface features (21). The opposing protruded retaining member components (30) are prevented from being pulled inside the cylindrical shaft member (2) because the outer diameter of each circular sector is greater to or equal to the outer diameter of the cylindrical shaft member, so a butt joint is formed between the two members.

[0029] FIG. 17 shows an embodiment of the cross sectional geometry of the ligating member (31 ) with corresponding cross sectional geometry for the opposing protruded retaining member (32) featuring opposing interlocking surface features (21 ). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (32) from being pulled inside the cylindrical shaft member (2).

[0030] FIG. 18 shows an embodiment of the cross sectional geometry of the ligating member (33) with corresponding cross sectional geometry for the opposing protruded retaining member (34) featuring opposing interlocking surface features (21 ). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (34) from being pulled inside the cylindrical shaft member (2).

[0031 ] FIG. 19 shows an embodiment of the cross sectional geometry of the ligating member (35) with the same cross sectional geometry for the opposing protruded retaining member (34) as featured in modification 6, featuring opposing interlocking surface features (21). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (34) from being pulled inside the cylindrical shaft member (2).

[0032] FIG. 20 shows an embodiment of the cross sectional geometry of the ligating member (35) with the same cross sectional geometry for the opposing protruded retaining member as contained in Modification 7, featuring opposing interlocking surface features (21). This component also features ingress preventing geometry (36). The ingress preventing geometry prevents the opposing protruded retaining member from being pulled inside the cylindrical shaft member (2).

[0033] FIG. 21 shows an embodiment of the cross sectional geometry of the ligating member (37) with corresponding cross sectional geometry for the opposing protruded retaining member (38) featuring opposing interlocking surface features (21). The opposing protruded retaining member (38) is prevented from being pulled inside the cylindrical shaft member (2) because its length is greater than or equal to the outer diameter of the cylindrical shaft member (2), so a butt joint is formed between the two members. [0034] FIG. 22 shows an embodiment of the cross sectional geometry of the ligating member (39) with corresponding cross sectional geometry for the opposing protruded retaining member (40) featuring opposing interlocking surface features (21). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (40) from being pulled inside the cylindrical shaft member (2).

[0035] FIG. 23 shows an embodiment of the cross sectional geometry of the ligating member (41) with corresponding cross sectional geometry for the opposing protruded retaining member (42) featuring opposing interlocking surface features (21). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (42) from being pulled inside the cylindrical shaft member (2).

[0036] FIG. 24 shows an embodiment of the cross sectional geometry of the ligating member (43) with corresponding cross sectional geometry for the opposing protruded retaining member (44) featuring opposing interlocking surface features (21). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (44) from being pulled inside the cylindrical shaft member (2).

[0037] FIG 25 shows an embodiment of the cross sectional geometry of the ligating member (45) with corresponding cross sectional geometry for the opposing protruded retaining member (46) featuring opposing interlocking surface features (21). This embodiment also features a cylindrical end piece member (22) with a cross bar feature (23). The cross bar feature prevents the opposing protruded retaining member (46) from being pulled inside the cylindrical shaft member (2).

[0038] What is claimed is:

Claims

1. A treatment device for the ligation and removal of large pedunculated colonic polyps, comprising:

a rigid snare member; and

a flexible ligating member having an open cross sectional slot in an external surface of the flexible ligating member which allows the rigid snare member and the flexible ligating member to act and be controlled as if they were a single member.

2. The treatment device of claim 1 or claim 2, wherein flexible ligating member has the rigid properties of the snare member.

3. The trcatement device o claim 1 , wherein the rigid snare member is embedded into the flexible ligating member.

4. A treatment device for the ligation and removal of large pedunculated colonic polyps, comprising:

a controlling handle having a single actuator with a singular movable member on a non-moving shaft member, configured for the dual functionality of both ligation and resection.

5. A treatment device for the ligation and removal of large pedunculated colonic polyps, comprising:

a ligation member having at least one of a long flat or a long curved internal cross sectional pro ile which maximizes the surface contact area with the polyp tissue i order to prevent trauma being applied to the tissue and avoid unwanted effects such as cold resection.

6. The treatment device of claim 5, wherein the ligation member includes structural rib features having a corrugating effect and give the member more strength and rigidity.

7. A treatment device for the ligation and removal of large pedunculated colonic polyps, comprising:

an opposing protruded retaining member configured to engage and match with the cross sectional geometry of the ligating member.

8. The treatment device of claim 7, wherein the opposing protruded retaining

member counteracts the tensile force acting on the ligating member and keeps the ligating member in its constricted form and the tissue in a state of ligation.

9. The treatment device of claim 7 or claim 8, further comprising:

opposing interlocking surface features which directly counteract the tensile force attempting to pull the two ends of the ligating member apart.

10. A treatment device for the ligation and removal o large pedunculated colonic polyps, comprising:

a snare member; and

a ligating member having a cross section configured so the open slot is no longer present in the ligating member and the controllability of the snare member is transferred to the ligation member by having 3 coupling points where the snare member passes through slots in the ligating member.

1 1. The treatment device of claim 10, wherein the slots are engineered so their cross sectional height is less than or equal to the cross sectional height of the snare member and therefore a friction fit bond is formed.

12. The treatment device of claim 10 or claim 1 1 , wherein the device has any number of friction fit coupling points including 1 , 2, 3, 4, 5, 6 or 7 coupling points.

13. A treatment device for the ligation and removal of large pedunculated colonic polyps, comprising:

a snare member; and

a ligating member (56), wherein the two members are orientated in a linear fashion, one after the other, in an end to end configuration, with the ligating member in the distal position closest to the polyp and the snare member in the proximal position closest to the controlling handle.

14. The device of claim 13, wherein the ligating member has two sections of material removed which form a pull back slot, into which the distal end loop of the snare member is positioned and allows the ligating member to be pulled back as the snare member is pulled back

15. The treatment device of any of claims 1 to 3, further comprising:

a cylindrical end piece member with cross bar feature or some variation of ingress preventing geometry.

16. A method of treating large pedunculated colonic polyps, comprising:

ligating the colonic polyp using the device of claim 1 ; and

resecting the polyp by passing electrical current into the polyp with the device used to !igate the polyp.

17. A method of treating large pedunculated colonic polyps, comprising:

ligating and removing a polyp by forming a friction fit bond with a snare member and a ligating member that is strong enough to allow the snare member and ligating member to be maneuvered and controlled as one member but will also allow for the snare member to be released from the friction fit bonds after ligation of the polyp stalk has taken place.