Patent Application
20110208158
This invention generally relates to medical devices and in particular to an apparatus, kit and method for endoscopic submucosal dissection using an injectable solution.
Minimally invasive medical procedures are performed in various passageways in the body using elongated instruments inserted through natural orifices or small surgical openings. In some procedures, it is desirable to treat some diseases using en bloc tissue removal through an elongate device, for example removing tissue lesions or polyps.
In some procedures, such as endoscopic submucosal dissection (ESD), a solution may be submucosally injected between layers of tissue to create a tissue elevation for removing the diseased tissue. Previously, injections of solutions such as saline or hyaluronic acid (HA) have been used to form an elevated tissue lesion for surgical removal. The elevated tissue is resected using a needle knife to cauterize the tissue or a snare to remove the elevated tissue section.
However, problems with the tissue resection occur when using solutions having a low viscosity such as saline. For example, the injected saline leaks out from between the tissue layers through the injection site, resulting in dissipation of the fluid, even when using multiple injection sites. Fluid dissipation leads to loss of leverage for removal of the tissue leading to risk of perforation of the underlying tissue and excessive bleeding. In addition, the viscosity of the saline solution is insufficient to cause enough pressure between the layers of the tissue to physically separate the layers to facilitate the removal of the diseased tissue. While solutions including HA are more viscous, HA solutions are expensive and not readily available in most endoscopy procedure suites. In addition, HA is hydrophilic, but requires dilution pre-injection that can lead to inconsistency with each injection.
There is a need for an apparatus and a method to provide an injectable solution for injection between tissue layers to form a tissue elevation and having sufficient pressure to physically break the cellular connections between the layers of healthy tissue and diseased tissue and to remain at the injection site for a sufficient time. In addition an apparatus and a method are needed to deliver an injectable solution to provide a tissue elevation that is present for a sufficient amount of time for a surgical procedure. There is also a need for a kit including an injectable solution having a consistent viscosity solution and a delivery apparatus for the injectable solution.
Accordingly, it is an object of the present invention to provide a kit and a method having features that resolve or improve on one or more of the above-described drawbacks.
The foregoing object is obtained in one aspect of the present invention by providing a kit for delivering an injectable solution to a tissue treatment site. The kit includes a housing having a chamber, a proximal portion and a distal portion. An injectable solution having a viscosity greater than about 10,000 cP is provided in the chamber. The kit also includes a plunger movably positionable within the proximal portion of the chamber, the plunger provides a seal at the proximal end portion. In some embodiments, a pressure gauge is also provided with the kit. A handle is connected to the housing and a plunger advancing member having a plunger handle is connected thereto. In some embodiments, the plunger advancing member is provided separate from the housing and includes a distal portion configured for operably connecting with the proximal portion of the housing. The kit also includes an inner shaft provided separate from the housing and having a proximal end portion configured for operably connecting with the distal portion of the housing for receiving the injectable solution therethrough and a distal end configured for insertion in to the tissue treatment site.
In another aspect of the present invention, a kit is provided. The kit includes a housing having a chamber, a proximal portion and a distal portion. An injectable solution having a viscosity greater than about 10,000 cP is provided in the chamber. The kit also includes a plunger movably position within the proximal portion of the chamber, the plunger provides a seal at the proximal end portion. A plunger advancing member handle connected to the housing having a plunger handle connected thereto is also provided separate from the housing in the kit. The kit also includes an inner shaft provided separate from the housing and having a proximal end portion configured for operably connecting with the distal portion of the housing for receiving the injectable solution therethrough and a distal end configured for insertion in to the tissue treatment site.
In another aspect of the present invention, a method of elevating a first tissue layer away from a second tissue layer is provided. The method includes connecting an inner shaft to a distal portion of a housing having a chamber therein, connecting a plunger to a proximal portion of the housing and advancing a distal end of the inner shaft to the first tissue layer and inserting the distal end into the first tissue layer. The method also includes distally advancing the plunger to advance an injectable solution having a viscosity greater than about 10,000 cP from the chamber through the inner shaft and into the tissue and injecting the solution into the first layer and elevating the first tissue layer away from the second tissue layer.
The invention is described with reference to the drawings in which like elements are referred to by like numerals. The relationship and functioning of the various elements of this invention are better understood by the following detailed description. However, the embodiments of this invention are not limited to the embodiments illustrated in the drawings. It should be understood that the drawings are not to scale, and in certain instances details have been omitted which are not necessary for an understanding of the present invention, such as conventional fabrication and assembly.
As used in the specification, the terms proximal and distal should be understood as being in the terms of a physician delivering the injectable solution to a patient. Hence the term “distal” means the portion of the device that is farthest from the physician and the term “proximal” means the portion of the device that is nearest to the physician.
A proximal portion 130 of the delivery device 100 is shown in
The plunger advancer member 143 is insertable into a proximal opening 152 of the housing 134 and fits on a portion of the plunger 142. The plunger 142 is advanceable toward the distal end portion 148 of the housing 134 to decrease the volume of the chamber 136 and advance the injectable solution into the tissue 110. In some embodiments, the plunger advancer member 143 is a screw-gear plunger having the plunger handle 144 at a proximal end 156 of the delivery device 100 and a distal end 158 received by the plunger 142 within the chamber 136 of the housing 134. The screw gear plunger member may include male or female threads or grooves that may be used to distally advance the plunger 142 to create pressure within the chamber 136 to force the injectable solution distally into the tissue 110. In some embodiment the plunger 142 may form a seal at the proximal end 156 so that the solution does not escape the proximal end 156. A seal (not shown) may be provided at the distal end 158 of the plunger 142 that seals the chamber 136 as the plunger 142 is distally advanced and prevents the injectable solution from flowing proximally past the plunger 142. The seal allows high pressure within the chamber 134 to distally advance the injectable solution through the inner shaft 114 without leaking. By way of non-limiting example, the seal may be an o-ring. In some embodiments, the seal may be provided in the form of a polytetrafluoroethylene (PTFE) tape. The PTFE tape may be wound around the end of the plunger 142 to form the seal between the plunger 142 and the housing wall 134. A distal seal may also be provided on the distal end of the housing 134 to seal the housing 134 for delivery and before the housing 134 is connected to a pressure gauge or a connector as discussed below.
The housing 134 may be adapted for withstanding positive displacement pressures associated with advancing injectable solutions having increased viscosity through the distal end 148 of the housing 134 and into the inner shaft 114. For example, the viscosity of the solution within the chamber 136 may be greater than about 10,000 cP. The housing 134 may be formed from any suitable material sufficient to withstand the pressure generated for a solution having a viscosity greater than about 10,000 cP. In some embodiments, the housing may accommodate a solution having a viscosity greater than about 30,000 cP. Materials for forming the housing may include, but are not limited to plastic, such as polycarbonate, and glass.
In some embodiments, the delivery device 100 includes a pressure gauge 175 as shown in
As shown in
As shown in
The connector 180 may also be released so that the outer catheter 116 is movably positionable relative to the inner shaft 114 to expose a distal end 186 of the inner shaft 114 as shown in
An embodiment of the delivery device 100 is shown in
The delivery device 100 may be provided in a kit 200 as shown in
In some embodiments, a kit 202 may also be provided with a plurality of housings 134 as shown in
As shown in
As shown in
An injectable solution suitable for use with the delivery device 100 and suitable for being provided within the housing 134 of the kit 200 is described below. The injectable solution is a pharmaceutically acceptable solution for use in humans and animals that has minimal tissue reactivity. In some embodiments, the injectable solution has a viscosity greater than about 10,000 cP, and in some embodiments, a viscosity greater than about 30,000 cP and greater than about 50,000 cP. The preferred viscosity for the injectable solution is between about 10,000 to 150,000 cP, and in some embodiment the preferred viscosity for the injectable solution is between about 30,000 cP and about 120,0000 cP, although other viscosities may be used. The viscosity of the injectable solution preferably should be high enough to separate the tissue layers. Non-limiting examples of suitable materials for inclusion in the injectable solution include methylcelluloses, such as carboxymethyl cellulose (CMC) and hydroxypropyl methylcellulose (HPMC), extracellular matrix proteins, elastin, collagen, gelatin, fibrin, agarose, and alginate or mixtures thereof. The injectable solution with be described with reference to CMC although one skilled in the art will understand that other suitable materials may also be used to form the injectable solution.
Suitable concentrations of the CMC for the injectable solution include about 1% to 10% CMC (e.g. about 1%, 1,5, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, or 10%). Preferably CMC concentrations range from about 2.5% to 3.5%, and more preferably about 3%. The CMC may be mixed with sterile water, saline or other pharmaceutically acceptable solution to provide a suitable concentration for injection. (CMC may be purchased from Sigma Aldrich, St. Louis, Mo.) The injectable solution may also include additional components, including, but not limited to dyes, such as food coloring, methylene blue or carbon black, and hemostasis regulators, such as vasoconstrictors, for example, epinephrine.
In operation, the CMC is premixed with a pharmaceutically acceptable solution at the manufacturer to the desired concentration for the injectable solution. The CMC injectable solution is loaded into the housing 134 at the manufacturer and the housing 134 is sealed under sterile conditions to maintain the sterility of the CMC injectable solution for delivery to the patient. The remaining components of the kit 200 are assembled together on the support member 88 and packaged for delivery to the physician.
The ESD procedure is described herein with reference to removal of a gastric lesion as shown in
The physician can monitor the depth of the injection required using the visualization port of the endoscope. An injection of saline or other pharmaceutically acceptable solution may be used to initiate the formation of the tissue pocket 126. The CMC injectable solution is injected into the same injection site through the inner catheter 114 in an amount sufficient to create the tissue pocket 126 for a time sufficient for the procedure. The CMC injectable solution is injected under sufficient pressure and with a sufficient volume and viscosity to break the cellular attachments between the first layer 120 and the second layer 122 at the tissue treatment site 110. A dye may be included with the CMC injectable solution to help the physician visualize the elevated portion of the tissue. The amount of CMC injectable solution injected to form the tissue pocket 126 is determined by the physician. Once the tissue pocket is formed, the inner shaft 114 is removed and an electrocautery device or snare is inserted into the working channel and advanced distally to the treatment site 110 and the diseased tissue removed.
The above Figures and disclosure are intended to be illustrative and not exhaustive. This description will suggest many variations and alternatives to one of ordinary skill in the art. All such variations and alternatives are intended to be encompassed within the scope of the attached claims. Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the attached claims.
This application claims the benefit of U.S. Provisional Application No. 61/306,100, filed Feb. 19, 2010, which is incorporated by reference herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61306100 | Feb 2010 | US |
