SURGICAL DELIVERY DEVICE AND METHOD

The present application relates to a surgical delivery device (10) suitable for submucosal dye delivery or for introduction or extraction of fluidic or gaseous material into or from tissue (T), the surgical delivery device comprising an elongate main body (12) defining an evacuatable chamber (18) internally thereof, a lateral window (20) in the body in communication with the chamber and a guideway (24a) extending through the body and into the chamber.

FIELD OF THE INVENTION

The present invention relates to a surgical delivery device for affecting various functions such as, but not limited to, submucosal dye delivery, introduction or extraction of fluidic or gaseous material to tissue, and any other applicable procedure.

BACKGROUND OF THE INVENTION

The invention addresses problems associated with the injection, extraction and/or relocation of fluids, solids and/or gases to a location below the tissue surface. The particular focus of the invention relates to endoscopic tattooing; the delivery of tattoo dye to the submucosa layer in the colon or intestine, but could also be used for many other applications for the delivery of other therapeutics below a layer of tissue, or for the extraction or relocation of fluid, solid or gas matter e.g. lesion margin identification and lymph node identification.

For surgical procedures requiring injection into the wall of the GI tract, considerable user-skill is required to control the depth of penetration and avoid leakage (too shallow an injection) and perforation (too deep an injection). There is also often a requirement for a second operator of the injection device. In the case of endoscopic tattooing, the aim is to inject tattoo dye into the submucosa. Currently, an exposed needle is used and the skill of the operator is required to locate the depth of the submucosa below the tissue. The aim of the current invention is to ensure material such as tattoo dye is injected consistently into the submucosa, and to make the procedure accessible to less skilled operators and to increase the speed and reliability of the procedure. Furthermore, as more expensive diagnostic dyes and therapeutics will soon be available, spillage/misplacement will have significant dosage and financial implications.

When performing polypectomy procedures such as EMR (endoscopic mucosal resection) or ESD (endoscopic submucosal dissection), the surgeon needs to quickly identify the site and margins of the lesion to be removed. After removal of the lesion, there might be need to operate on the site again to remove any residual cancerous tissue or lymph node metastases. To mark the location of a lesion, there are several options available which can be performed either at the time of initial lesion detection or later at its removal (through polypectomy or laparoscopic removal of a section of tissue). These include measuring the distance from the anus to the site of the lesion, intraoperative colonoscopy, endoscopic metal clips or endoscopic tattooing. Endoscopic tattooing marks the location of the lesion by injection of a dye into the submucosa. In order to enhance the quality of dye injection, prior saline injection to the submucosa has been proposed to decrease the likelihood of misdirected injection. There have been various dyes used for endoscopic tattooing.

Current procedures use an exposed needle (often referred to as endoscopic sclerotherapy needles) to try and pierce tissue down to the submucosal layer, with only manual control. The current invention avoids the use of an exposed needle, improving safety of the procedure. The invention also controls the depth of needle penetration, ensuring delivery of the needle to the appropriate location. In procedures like endoscopic tattooing, india ink leakage can lead to harmful complications such as abscess formation or peritonitis or create difficulties in surgical planning. It is anticipated that when higher commodity dyes and therapeutics are used in targeted injection for the management of colorectal disease, reliable methods to control the volume of dose injected will become of even more significance.

The present invention seeks to address the above mentioned problems.

FIELD OF THE INVENTION

According to a first aspect of the present invention there is provided a surgical delivery device comprising an elongate main body defining an evacuatable chamber internally thereof; a lateral window in the body in communication with the chamber; and a guideway extending through the body and into the chamber.

Preferably, the guideway is shaped and dimensioned to permit the passage of a surgical instrument therealong.

Preferably, the guideway is shaped and dimensioned to permit the passage of a needle therealong.

Preferably, the guideway opens onto the chamber.

Preferably, the lateral window is shaped and dimensioned to permit a quantity of tissue to be drawn into the chamber via negative pressure applied to the chamber.

Preferably, the guideway comprises a proximal portion on one side of and terminating at the chamber, and a distal portion on an opposed side of and extending from the chamber.

Preferably, the proximal portion and the distal portion are coaxially aligned.

Preferably, the guideway comprises a cylindrical bore.

Preferably, the main body defines an evacuation circuit in communication with the chamber and operable to apply a negative pressure to the chamber when the lateral window is occluded.

Preferably, at least a portion of the evacuation circuit extends substantially parallel to the guideway.

Preferably, the chamber comprises a stop positioned to limit the depth to which tissue may be drawn into the chamber.

Preferably, the evacuation circuit extends around the stop to establish two or more regions within the chamber at which negative pressure may be applied.

Preferably, the main body comprises an atraumatic distal tip.

Preferably, the chamber is located adjacent the distal tip.

Preferably, the surgical delivery device comprises a needle captured for axial displacement within the guideway between a retracted position in which a tip of the needle is located in the guideway and an extended position in which the tip of the needle is located within or beyond the chamber.

Preferably, a tip of the needle is at least partially displaceable into the chamber.

Preferably, the tip of the needle is displaceable beyond the chamber.

Preferably, the tip of the needle is asymmetric.

Preferably, the needle comprises a lumen and an outlet providing fluid communication between the lumen and an exterior of the needle.

Preferably, the tip of the needle is sealed from the lumen.

Preferably, the outlet is located in a sidewall of the needle.

Preferably, the outlet is oriented towards the lateral window.

Preferably, the outlet is located adjacent the tip of the needle.

Preferably, the surgical delivery device comprises a positioning system adapted to maintain a particular orientation and/or to limit displacement of the needle as it undergoes reciprocal movement in the guideway.

Preferably, the positioning system is operable to prevent rotation of the needle about a longitudinal axis thereof.

Preferably, the alignment system is operable to stop the longitudinal displacement of the needle with the outlet located at a predetermined position within the chamber.

According to a second aspect of the present invention there is provided a method of delivering a substance to or from tissue, the method comprising the steps of locating a device having a main body defining an evacuatable chamber internally thereof and a lateral window in the body in communication with the chamber such that the window is located adjacent the target tissue; evacuating the chamber in order to draw the target tissue at least partially into the chamber; and delivering a substance into or out of the tissue while located in the chamber.

Preferably, the method comprises the step of advancing a surgical instrument into the chamber when the tissue has been drawn into the chamber such as to pierce the tissue; and delivering the substance through the surgical instrument.

Preferably, the method comprises the step of advancing the surgical instrument past the chamber in order to capture the target tissue thereon.

Preferably, the method comprises the step of evacuating the chamber through two or more channels.

Preferably, the method comprises the step of drawing the target tissue against a stop located within the chamber.

As used herein, the term “upstream” is a relative term intended to indicate a position or motion of one item or location relative to another item or location, in particular from a proximal position or location towards a distal position or location.

As used herein, the term “downstream” is a relative term intended to indicate a position or motion of one item or location relative to another item or location, in particular from a distal position or location back towards a proximal position or location.

As used herein, the term “substance delivery” is intended to mean the supply and/or withdrawal of a substance, for example a liquid or gas, but potentially also a solid and/or a combination thereof, to or from a target tissue, whether endoscopically, laparoscopically, subcutaneously or otherwise.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now toFIGS. 1-5of the accompanying drawings there is illustrated a surgical delivery device according to an embodiment of the present invention, generally indicated as10, which is adapted to deliver a fluid, for example a tattoo dye (not shown) to a target region or portion of tissue T as described in detail hereinafter. It should however be understood that the device10and alternative embodiments thereof may be utilised or adapted to deliver other substances such as solids, liquids, gases or a combination thereof, in addition to being adapted to extract a sample of material from the target region or portion of tissue T or the like, for example performing a biopsy or the like. Additionally the delivery device10of the invention could be utilised to relocate material such as tissue to a different anatomical location.

The device10comprises a main body12which in the embodiment illustrated is elongate and cylindrical in form, such that it may pass through the lumen of a delivery conduit (not shown) or the like, and may be provided at or as the head of a steerable catheter (not shown) or the like in order to allow the delivery device10to be advanced into the desired position adjacent the target section of tissue T. The main body12comprises a proximal end14and a distal tip16which is preferably rounded or blunt in order to provide an atraumatic tip. The main body12defines a chamber18internally thereof and which is externally accessible via a lateral window20provided in a sidewall of the main body12on one side thereof. The chamber18is substantially cylindrical in the preferred embodiment, although any other suitable shape, volume and/or orientation may be employed. In the embodiment illustrated the chamber18and lateral window20are located adjacent the distal tip16, although it will be appreciated that the position and orientation of the chamber18and window20may be varied as required, for example depending on the direction from which the surgical device10is to be advanced into position relative to the target tissue T.

The surgical delivery device10additionally comprises an evacuation circuit which in the embodiment illustrated is comprised primarily of an elongate channel22which extends longitudinally through the main body12from the proximal end14into fluid communication with the chamber18in order to allow the chamber18to be evacuated via the channel22, by applying a negative pressure through the channel22via any suitable vacuum pump (not shown) or the like which may be connected to the channel22in conventional fashion. It will of course be understood that the channel22could be partially or fully located externally of the main body12but this would be a less preferred design choice in particular where the delivery device10is to be passed through a catheter or the like. In additional any other suitable functional means of effecting evacuation of the chamber18may be employed in place of the channel22.

As will be described in greater detail hereinafter, the surgical delivery device10may thus be positioned adjacent the target tissue T such that the lateral window20overlies at least a portion of the target tissue T, which thereby effectively occludes the lateral window20. Thus once negative pressure is applied to the chamber18via the channel22the target tissue T will be drawn into the chamber18as illustrated inFIGS. 2 and 3. The negative pressure may be maintained until the desired surgical procedure to be effected is complete, or may be released earlier if appropriate.

The surgical delivery device10further comprises a guideway24which, in the embodiment illustrated, runs essentially parallel to the channel22from the proximal end14into the chamber18, and preferably extends beyond the chamber18to or close to the distal tip16. The guideway24thus comprises a proximal portion24awhich is located upstream of the chamber18and a distal portion24bwhich is located downstream of the chamber18, relative to movement through the guideway24from the proximal end14towards the distal tip16. The proximal portion24aand distal portion24bare axially aligned with one another and are preferably of the same cross section and dimension, although this is not essential.

The surgical delivery device10additionally comprises a surgical instrument which in the embodiment illustrated is in the form of a needle26which is captured in and slidable longitudinally along the guideway24as described hereinafter. The needle26is hollow and thus defines a lumen28therein, while also comprising a sealed and pointed tip30which in the embodiment illustrated is an asymmetric tip but may be of any other style or configuration. The needle26additionally comprises an opening or aperture32in a sidewall of the needle26adjacent the tip30and which thus allows fluid communication between the lumen28and the exterior of the needle26. The needle26is reciprocally displaceable within the guideway24from a retracted position as illustrated inFIGS. 1 and 2in which at least the needle tip30and adjacent portion of the needle26are located in the proximal portion24aof the guideway24, and an extended position as illustrated inFIG. 3in which the tip30is advanced into the chamber18, and more particularly such that the aperture32is located within the chamber18for the reasons described hereinafter. Depending on the design and dimensions of the needle26, and in particular the tip30, the distal portion24bof the guideway24can serve to at least partially accommodate the tip30when the needle26is advanced to position the aperture32within the chamber18, as the tip30might otherwise impact the sidewall of the chamber18thereby blunting the needle tip30over time.

Thus in use with the surgical delivery device10located adjacent the target tissue T, which in the embodiment illustrated comprises a layer of muscle M, submucosa S and the epithelium E, negative pressure is applied to the chamber18via the channel22, thereby drawing the portion of target tissue T into the chamber18as illustrated inFIG. 2. During this initial evacuation phase the needle26is in the retracted position in which the tip30is located downstream of the chamber18within the proximal portion24a.

Once the target tissue T is contained within the chamber18the needle26is advanced such that the tip30enters the chamber18and will therefore pierce the target tissue T, the needle26being advanced until the aperture32is located internally of the target tissue T, and in the embodiment illustrated is located within the submucosa S. At this point a substance, in particular a fluid and most particularly a tattoo dye, can be delivered to the submucosa S via the lumen28and aperture32. It will of course also be appreciated that the aperture32and lumen28could be used to withdraw a substance from within the tissue T, effectively delivering a substance away from the target tissue T.

Once a suitable quantity of the dye or other substance has been delivered to the tissue T the needle26can be withdrawn into the retracted position, at which point the negative pressure can be released from the chamber18allowing the tissue T to be released from the device10. The device10can then be withdrawn by any suitable means, or may be repositioned to another site to delivery further quantities of the dye or other substance.

Referring toFIG. 4, as a modification to the above methodology, the aperture32may be positioned longitudinally further back from the tip30of the needle26, and when the target tissue T is then drawn into the chamber18under negative pressure the needle26can be advanced from the retracted position such that the tip30enters the tissue T and passes through the tissue T and continue upstream of the chamber18, to enter into the distal portion24bof the guideway24. In this way the portion of target tissue T is effectively skewered by the needle26, and it is then possible to release the negative pressure from the chamber18and the tissue T will remain captured on the needle26. The dye or other substance can then be delivered into or away from the target tissue T as hereinbefore described, before again withdrawing the needle26into the retracted position to release the tissue T.

Referring now toFIGS. 5 to 9there is illustrated an alignment system34which optionally but preferably forms part of the surgical delivery device10, and is operable as hereinafter described to maintain a particular angular orientation of the needle26and/or limit the range of axial displacement that the needle26can undergo along the guideway24. The alignment system34comprises collar36within which a rear portion of the needle26is captured in order to prevent the needle from undergoing any angular rotation about a longitudinal axis thereof, principally to ensure that the aperture32remains in a particular orientation, and preferably facing towards the lateral window20when the aperture32of the needle26is located within the chamber18. This ensures that delivery of the dye or other substance via the aperture32is injected into the submucosa S and at a position which will improve penetration and dispersion of the dye into the tissue T. It is also the provision of the aperture32in the sidewall of the needle26, as opposed to at the tip30, which permits this functionality of improved penetration and dispersion by delivering the dye into the correct location with the target tissue T. It is also for this reason that the tip30of the needle26is sealed in order to ensure that the dye or other substance is only injected via the aperture32.

The alignment system34may additionally comprise a dual lumen tube38within which the collar36and captured portion of the needle26are located as illustrated inFIGS. 8 and 9. The tube38may be dimensioned to pass along the guideway24, or the collar36including the needle26may be reversibly extendible out of the dual lumen tube38in order to effect extension and retraction of the needle26as hereinbefore described. Suitable mechanical limiters (not shown) may be provided as part of the alignment system34in order to limit this axial displacement of the needle26, in order to ensure that the needle26cannot be over extended when piercing the target tissue T in the chamber18, and thereby ensuring that the aperture32is always located at the correct position, preferably centrally of the chamber18. This limitation of the extension of the needle26is also the mechanism by which it may be ensured that the sharpened tip30does not need to be used as a means of arresting the extension of the needle26, which would require contact of the tip30with a surface and which would ultimately blunt the tip30.

Referring now toFIGS. 10 to 12there is illustrated a modified embodiment of a surgical delivery device according to the present invention, generally indicated as110. In this modified embodiment like components have been accorded like reference numerals unless otherwise stated perform a like function.

The device110again comprises a main body112having a proximal end114and a distal tip116, and defining a chamber118internally thereof which is open to the exterior of the device110via a lateral window120. The device110comprises an evacuation circuit including a channel122which is provided in order to allow negative pressure to be applied to the chamber118during use. A guideway124is provided within the body112in order to permit a needle126to be advanced into and optionally past the chamber118as hereinbefore described with reference to the first embodiment.

Unlike the first embodiment the surgical delivery device110additionally comprises a stop50positioned within the chamber118, or at the interface between the chamber118and the channel122, which provides a dual functionality as hereinafter described. Firstly, the stop50effectively splits the evacuation channel122into two branches, a proximal branch122aand a distal branch122b,thereby creating a double suction force on the target tissue T from two spaced locations, while simultaneously limiting the depth to which the target tissue T may be drawn into the chamber118, which combined with the double suction force achieves a more stable and even positioning of the tissue T within the chamber118. This effectively creates a larger footprint of tissue T within the chamber118, providing a greater length or volume of tissue T aligned with the needle126and into which the needle126may be advanced for delivering or extracting substances into or out of the tissue T. The guideway124may also comprise a proximal portion124aand a distal portion124bin order to allow the above described skewering of the target tissue by the needle126, as illustrated inFIG. 12, thereby enabling the negative pressure to be released once the target tissue T has been skewered.

It will therefore be appreciated that the surgical delivery device of the invention overcomes various problems associated with the existing techniques and devices used for such procedures, in particular the problems of repeatability in relation to setting the depth of insertion of the needle; dependence on the skill of the clinician; the time taken to perform the procedure, which currently involves multiple potentially redundant steps; the requirement for an additional operator to actuate the needle to carry out the injection; and the complications which can arise, such as transmural injection, liquid spillage, involuntarily pinching which can occur.

The present invention provides improved safety whereby the design of the surgical delivery device10;110prevents pinching of the target tissue, and the injection can only be preformed when the tissue is being drawn into the chamber of the device, which occurs only when suction has been previously activated by the operator, thereby decreasing the risk of involuntary pinching. The stable and even positioning of the tissue in the chamber provides a high level of control over the depth of insertion of the needle into the tissue, and the device of the invention allows repeatability of the procedure since the distance between the axis of the needle and the mechanical limit into the chamber of the device is constant, the injection therefore being performed to the same depth repeatedly.