WO2007083305A2

WO2007083305A2 - Access enabling device for surgical procedures

Info

Publication number: WO2007083305A2
Application number: PCT/IL2007/000064
Authority: WO
Inventors: Shay Dubi; Tovy Sivan; Eran Hirszowicz
Original assignee: Ez Surgical Ltd.
Priority date: 2006-01-17
Filing date: 2007-01-17
Publication date: 2007-07-26
Also published as: WO2007083305A3

Abstract

The present invention is primarily directed to a surgical retractor capable of being manipulated from a closed conformation to an open conformation and vice versa, wherein said retractor in its open conformation comprises a tube-like frame, such that the inner face of said frame defines the outer boundary of an internal space, and wherein said internal space is essentially eliminated when said retractor is in its closed conformation. The invention further provides methods of retracting tissues and/or organs during surgical procedures using the aforementioned surgical retractor.

Description

Access Enabling Device for Surgical Procedures

Field of the Invention

The present invention relates to a surgical retraction instrument used to retain or hold back internal organs in the operative region during either open or minimally invasive endoscopic surgery.

Background of the Invention

Surgical procedures can be divided into two fundamental types, conventional (open) surgery and Minimally Invasive Surgery (MIS or endoscopic surgery) . Conventional surgery generally involves a relatively large incision with direct visualization (e.g. with the "naked eye") of the area being operated upon. Examples of conventional surgery include various types of heart and bowel surgery. Endoscopic surgery involves indirect visualization of the operative field with a small camera or optic fibers. Endoscopic surgery is generally achieved by means of making multiple small incisions through which the camera and surgical instruments are inserted. The instruments perform their functions inside the body but are operated- by use of their handles outside the body. Examples of endoscopic surgery include endoscopic appendectomy and laparoscopic cholecystectomy. Endoscopic surgery can also be performed through existing, natural orifices (for example, prostate surgeries and gastrointestinal surgeries performed through the relevant natural orifices) .

In both conventional surgery and minimally invasive endoscopic surgery, the surgeon is required to expose and handle delicate tissues deep within the body cavities. This requires opening a surgical window, or workspace, through which the procedure can be performed. The surgical window should be optimized such that it is wide enough to view and work within the treatment area, taking care not to damage the surrounding tissue. Retractors consisting of a blade and a ^' handle held by a nurse or an assistant surgeon have been used in surgery for centuries. More recent retractors attach to the operating table or some other external object in various methods and maintain a position dictated by the surgeon . In endoscopic surgery, the problem is most commonly addressed by using a grasper instrument to hold the organs in place. Other solutions are retractors inserted through an additional incision, which may be expanded within the body and either held by an assistant or fixed to a stable object outside the body, most commonly to the operating table. The use of a grasper device or of currently used endoscopic retractors requires an additional hole in the abdominal wall and an additional trocar. The grasper is operated by a surgeon/assistant, thus focusing some of his attention and occupying at least one of his hands with a relatively unimportant task. Furthermore, holding an organ with the grasper for a considerable period of time and moving it around while exerting all the force at one point, may harm the tissue. In addition, currently used retractors obstruct the view and require frequent repositioning.

Endoscopic surgery poses many additional problems for the surgeon, such as mastering of non-intuitive tools, performing the procedure at one place while looking in another direction and lack of immediate manual feedback. An additional important obstacle is the tendency of certain' tissues or organs to invade the surgical workspace and occlude the visual field, such as small bowel loops descending into the pelvis while performing pelvic surgery and healthy tissues covering a tumor during resection. An important case study for the importance of the surgical access window is laparoscopic cholecystectomy, which carries specific procedure-related complications due to the unique endoscopic procedure (A. Shamiyeh, W. Wayand: Laparoscopic cholecystectomy: early and late complications and their treatment. Langenbecks Arch Surg (200.4) 389:164-171.). Over 600,000 patients are operated annually for gallstone disease in the US, and over 75% of the operations are performed by laparoscopy. However, with the widespread acceptance of this operation all over the world, the spectrum of complications in gallstone surgery has changed and encompasses typical complications related to minimal invasive surgery, such as bleeding from vascular injury, biliary leaks, bile duct injuries and Bowel injuries.

The incidence of major vascular injuries in laparoscopy (including aorta, iliac vessels, vena cava, inferior mesenteric arteries and lumbar arteries) is 0.07%-0.4%, for minor injuries (branches of the epigastric vessels, mesenteric and omental vessels) is 0.1%-1.2% and the mortality rate is 0.05%-0.2% (Catarci M, Carlini M, Gentileschi P, Santoro E (2001) Major and minor injuries during the creation of pneumoperitoneum. A multicenter study on 12,919 cases. Surg Endosc 15:566- 569). Biliary complications include Spillage of gallstones and biliary leaks, and are highly affected by the surgeon's experience (Sarli L, Pietra N, Costi R, Grattarola M (1999) Gallbladder perforation during laparoscopic cholecystectomy. World J Surg 23:1186-1190.). The most serious lesion of this type is transection of the bile duct, which is usually a consequence of the inadequate exposure (E. M. Targarona, C. Marco, C. Balague', J. Rodriguez, E. Cugat, C. Hoyuela, E. Veloso, and M. Trias. How, when, and why bile duct injury occurs-. Surg Endosc (1998) 12: 322-326.) Bowel injuries may occur during the insertion of the trocars and during dissection of the tissues. They often remain undetected during the operation and have been reported to occur in up to 0.87% of cases (Bishoff JT, Allaf ME, Kirkels W, Moore RG, Kavoussi LR, Schroder F (1999) Laparoscopic bowel injury: incidence and clinical presentation. J Urol 161:887- 890.)

As previously described, the problem of surgical site access is currently addressed by using two modalities of instruments: graspers that hold the organs in place and retractors that prevent tissues from interfering with the surgical window. The use of both of these technologies has significant limitations, such as:

^■ Difficult access despite their use, limiting view in the area where the retractor is used

^■ Uncomfortable procedure and working space, since these tools are robust and space occupying

■ They require an additional entry point in endoscopic surgery and an additional trocar, thus increasing cost of the procedure and resulting in safety problems and inferior cosmetic results

■ A surgical assistant is usually required to use the tools for tissue retraction (The grasper is operated by a surgeon, focusing his attention and occupying at least one of his hands with a relatively unimportant task) , thus increasing the work-force needed for the procedure and the cost of the procedure

■ Difficult visualization, since these tools are not transparent, and block the view of the retracted tissues

■ The force used ' for retraction is uncontrolled

In summary, good exposure of the surgical space is essential for clinical success of the procedure, especially in endoscopic procedures, current surgical tools do not meet the need for optimizing the surgical window and there is a significant need for devices that can optimize the surgical exposure by retraction of the surrounding tissues.

SUMMARY OF THE INVENTION

There is therefore provided according to the present invention, a novel type of tissue retractor which can be inserted into the body cavity while in a contracted or collapsed state (i.e. having a much smaller diameter than in the open conformation, and lacking the internal cavity of that conformation) , and then allowed to expand within the surrounding tissues to create a discrete workspace (surgical window) . The purpose of the device of the invention is to widen the access area to the treatment site, to retract the surrounding tissues and to maintain the resultant size of the access area. The structure of the device of the invention, in outline form, in its fully expanded (open) conformation, consists of a tube-like structure open at both ends, the wall of the tube optionally comprising a plurality of vertically and/or horizontally disposed rods (or elements) and optionally comprising a membrane or other thin covering layer attached to said rods. The retractor of the invention can anchor to the tissues surrounding the surgical window, and does not require any external anchoring outside the treated area, although such external anchoring may be used if desired. The device of the invention thus prevents any unwanted protrusion of retracted tissues into the workspace, enables good access to the treated area and allows the surgeon to comfortably and safely work within the surgical window. The retractor of the invention may be self expanding - i.e. upon placement at the desired surgical or other site, the force, structure or mechanism that maintains the device in its collapsed state is released, thereby permitting the retractor to expand 'spontaneously¹, without the need for any further manipulation. Alternatively, the retractor may be manually deformable, such that upon placement at the desired site, the operator pushes or bends outwards the relevant portions of the collapsed device into various different shapes and dimensions in order to achieve retraction of the relevant tissues. The device may be constructed of a plastic or metal skeleton, which may be covered by a transparent membrane or covering, constructed by an appropriate polymer or other appropriate material.

The device of the invention has the following advantages:

^■ Clear working space

^■ 3D access and view

■ Single entry point

^■ Single user

^■ Low cost disposable device

In summary, the device of the invention may have the benefits of simplifying surgical procedures, saving surgeon time and improving patient safety.

Thus, the present invention is primarily directed to a surgical retractor capable of being manipulated from a closed conformation to an open conformation and vice versa, wherein said retractor in its open conformation comprises a tube-like frame, such that the inner face of said frame defines the outer boundary of an internal space, and wherein said internal space is essentially eliminated when said retractor is in its fully closed conformation.

The aforementioned phrase "internal space is essentially eliminated" is intended to convey the meaning that the internal space of the retractor is either completely eliminated or, alternatively, that the internal space is reduced to the maximum possible extent, in accordance with the limitations imposed by the structure and dimensions of the rigid elements and materials of which said retractor is constructed.

The term 'tube-like frame' is intended to convey the meaning that the frame of the presently-disclosed device is a three- dimensional structure that forms the external boundary of an internal space. While the tube-like frame may, in a preferred group of embodiments have an outline shape that is generally cylindrical, it may also be conical, frusto-conical, spherical, elongated spheroid, flattened spheroid or any other suitable shape that defines an internal space that will provide a convenient surgical window. Similarly, the device of the present invention may be constructed with a variety of different cross-sectional shapes, including (but not limited to) circular, elliptical, irregular, rectangular or any other polygonal shape. In one particularly preferred embodiment, for example, the cross-sectional shape is essentially pentagonal, the sides of said pentagon being curved, while the general three-dimensional shape is generally cylindrical and conforms to the shape of the structure generally known as a 'Chinese lantern'.

In one particularly preferred embodiment of the invention, the dimensions of said retractor in its closed conformation render it suitable for endoscopic delivery (e.g. through a trocar).

While in some embodiments of the present invention the retractor frame is left uncovered, in other embodiments said frame is covered with a membrane. Such a membrane will generally be constructed from one or more biocompatible elastomers and/or polymers. In a particularly preferred embodiment, the membrane is transparent.

In one particularly preferred embodiment of the present invention, the surgical retractor is capable of self-expanding from a closed conformation to an open conformation as a result of outwardly directed elastic forces generated within the frame and/or membrane. This particular embodiment may be implemented by incorporating a restraining element (e.g. a clip, girdle or latch) into the retractor, the purpose of which is to .maintain the device in a fully closed, collapsed state. Upon release of the restraining element (e.g. after the retractor has been delivered to its intended working site) , the retractor self-expands into its open position.

In another preferred embodiment, the retractor is capable of being manipulated from a closed conformation to an open conformation and vice versa by means of manual deformation of the frame (e.g. by the pulling and pushing of the frame and/or covering membrane in the required directions) . It is to be emphasized that in this embodiment of the presently-disclosed device, the "plastic" deformation of the retractor into an open position may be used to cause said retractor to open either fully or partially, and in either a symmetrical or asymmetrical manner.

In one preferred embodiment, the frame of the retractor comprises a plurality of vertically and/or horizontally disposed elements (e.g. rods). These elements may be identical or similar to each other in shape and structure. Alternatively, the frame may comprise more than one type of vertically disposed element and/or more than one type of horizontally disposed element, each type being characterized by having different physical properties (e.g. resiliency, elasticity, rigidity etc.).

In one particularly preferred embodiment, at least one type of vertically-disposed and/or horizontally-disposed element is represented by a wire spring such as a spring having a series of angled portions. In another preferred embodiment, one or more of the vertically and/or horizontally disposed elements are constructed from a plurality of telescopic (or otherwise overlapping) segments.

In yet another preferred embodiment of the present invention, the surgical retractor further comprises a plurality of connection elements attached to the proximal end of the vertically disposed elements, wherein said connection elements are suitable for connecting pulling wires to said vertically disposed elements, such that said wires may be used to externally control the diameter of said retractor. This control mechanism will be described in more detail hereinbelow, with reference to the figures.

The present invention also encompasses several different forms of frame (in addition to the frame comprising a plurality of longitudinal and horizontal elements that was disclosed hereinabove) . Thus, in one embodiment, the frame has a helical structure that is constructed from one or more lengths of wires that are elastically-deformable. In another embodiment, the frame comprises a basal ring to which is attached a plurality of elastic arms extending longitudinally and radially therefrom. The elastic arms may be constructed in any suitable manner, but in one preferred embodiment they are constructed from wires formed into an inverted 'U' shape. This is, however, just one non-limiting example, many other shapes also being possible, all of which fall within the scope of the present invention. In a further preferred embodiment, the frame may be constructed from one or more elements that overlap in a circumferential plane, thereby permitting the diameter of said retractor to be altered by means of manipulating the degree of overlap between said overlapping elements .

In a further particularly preferred embodiment of the retractor of the present invention, the frame has a circular cross-sectional shape, and is constructed of a plurality of longitudinally-disposed elements, the three dimensional form of said frame being frusto-conical or conical.

All of these various implementations of the device of the present invention will be described hereinbelow, with reference to the appended drawings .

In another aspect, the present invention is also directed to a method for retracting tissues and/or organs during an open surgical procedure comprising the steps of: providing a surgical retractor as disclosed hereinabove, inserting said retractor in its closed conformation through the external layers of the surgical incision, positioning said retractor at the desired operating location, manipulating said retractor from its closed conformation to an open conformation, such that the required tissues and/organs are displaced from the operating location, thereby providing clear visual and instrumental access to said operating location through the internal space of said retractor. Furthermore, the present invention also provides a method for retracting tissues and/or organs during an endoscopic surgical procedure (e.g. a laparoscopic procedure) comprising the steps of: insertion of one or more trocars through the external tissues overlying the operating site, ^• providing a surgical retractor of the type disclosed hereinabove, delivering said retractor in its closed conformation through one of said trocars, positioning said retractor at the desired operating location, manipulating said retractor from its closed conformation to an open conformation, such that the required tissues and/organs are displaced from the operating location, thereby providing clear visual and instrumental access to said operating location through the internal space of said retractor.

In either of the above-disclosed methods, the step of manipulating said retractor from its closed conformation to an open conformation may comprise the release of a restraining element, thereby permitting the self-expansion of said retractor.

In the case of the method for use in conventional open surgical procedures, the step of manipulating said retractor from its closed conformation to an open conformation may comprise the manual manipulation of the frame and/or membrane of said retractor. In a further variant of this method, said method , may further comprise the steps of providing external anchoring means and using said means to anchor the retractor to tissues and/or organs located outside of the operating location. Brief Description of the Drawings

The present invention is illustrated by way of example in the figures of the accompanying drawings, in which like references indicate similar elements and in which:

Fig. 1 schematically illustrates an exemplary embodiment of the invention;

Fig. 2 schematically illustrates another exemplary embodiment of the invention;

Fig. 3A schematically illustrates another exemplary embodiment of the invention and Fig. 3B schematically illustrates the invention in use during cranial surgery ;

Fig. 4 schematically illustrates the invention in use during laparoscopic surgery ;

Fig. 5A schematically illustrates another exemplary embodiment of the invention and Fig. 5B schematically illustrates the invention in use during surgery;

Fig. 6 is a photograph of the exemplary embodiment of the invention illustrated in figure 3A;

Fig. 7A schematically illustrates an external manipulator of an exemplary embodiment of the invention and Fig. 7B schematically illustrates an exemplary mechanism of the external manipulator;

Fig. 8A schematically illustrates another exemplary mechanism of the external manipulator of the invention in a closed position and Fig. 8B illustrates the mechanism of the external manipulator of the invention in an open position ;

Fig. 9A schematically illustrates another exemplary embodiment of the' invention and Fig. 9B schematically illustrates the invention in use during surgery; Fig. 1OA and 1OB schematically illustrate another exemplary embodiment of the invention;

Fig. HA schematically illustrates a view from above of another exemplary embodiment of the invention and Fig. HB schematically illustrates the embodiment of HA from a lateral view;

Fig. 12A schematically illustrates another exemplary embodiment of the invention in a closed position; Fig. 12B schematically illustrates another exemplary embodiment of the invention in a partially-expanded position and Fig.l2C schematically illustrates the embodiment of 12A in an open position;

Figs. 13A and 13B illustrate a further umbrella-shaped embodiment of the present invention in its closed (Fig. 13A) and fully open (Fig. 13B) positions; and Fig. 14 is a flowchart demonstrating the steps of an endoscopic surgical procedure performed with the device of the invention.

Detailed Description of Preferred Embodiments

The present invention is directed to a method and apparatus for improving the surgical window during open and endoscopic surgical procedures by using a tissue retraction device that may be inserted into the surgical treatment area in a contracted state, the device is then expanded within the treatment site, inducing radial forces on the surrounding tissue. The aforementioned forces both anchor the device in place and prevent external tissues from penetrating into the surgical window and interfering with the surgeons ' view of the treatment site or access into the site.

In a preferred embodiment of the invention the device is self expanding, utilizing a spring-like mechanism. In another embodiment of the invention the device is not self expanding, but is in a "plastic" state, thus requiring external forces in order to expand the device.

Exemplary materials for construction of the device of the invention are biocompatible polymers and metals, as will be described hereinbelow.

In a preferred embodiment of the invention the device comprises a skeleton, which may be covered by a transparent membrane or thin covering or webbing. Exemplary materials for construction of the covering of the device of the invention are elastomers and polymers such as silicon and polyurethane .

Fig. 1 is a schematic diagram illustrating a perspective view of an exemplary embodiment of the device 10 of the invention, having a tubular formation with exemplary longitudinal rods 50 and exemplary horizontal rods 40, forming a plurality of slots parallel to the longitudinal axis of the device. Opening 30 is approximated to the tissue which is to be treated, and opening 20 is the access plane through which the surgeon can insert the surgical tools into the surgical working space, within the device 10. In a preferred embodiment of the device Rods 50 and 40 are flexible, thus allowing contraction of the device for insertion through a small aperture (for example a trocar in endoscopic surgery) and allowing expansion of the device within the surgical working space after its insertion. An advantage of the elastic embodiment is the ability for self expansion of the device within the body tissue, thus allowing a self-anchoring tissue retraction device. In addition, a self expanding device may exert predetermined forces on the tissues, thus reducing the risk of tissue damage. In another preferred embodiment of the device the rods are in a "plastic" state, i.e. require external force for movement and will stay in the new position after they are moved. An advantage of a "plastic" embodiment is that the surgeon may move and tightly control the 3D form of the device, and constantly change its size and structure according to the needs during the procedure .

The device 10 may be constructed from a single type of material, or, from a plurality of different types of materials. In a preferred embodiment, the device may be constructed from a single type of material, or, from a plurality of different types of materials, exhibiting the physicochemical property and behavior of elasticity, whereby the device, in general, and, the at least one elastic component, in particular, are self-expandable. For example, such material is selected from the group consisting of a pure metal, a metal alloy, plastic, polymer and combinations thereof. Exemplary pure metals are tungsten, platinum, and, titanium. Exemplary metal alloys are nitinol, and, stainless steel. For example, as an integral single, continuous, elastic component, the device may be designed, configured, and constructed, by starting with a single, unitary, preferably metal, tube, followed by removing, for example, by laser cutting, selected material from the tube, until only the desired geometry, shape, and dimensions, remain. Alternatively, the device of the invention may be constructed by bending a wire or multiple wires into the desired shape. Industrial bending machinery may be used to bend the wire into the desired .shape, and the wires may be connected by welding, in the case that multiple wires are used, suitable metal wires may be obtained, for example, from Allvac Inc., Monroe, NC.

Referring again to FIG.l, The device 10 of the invention may be covered by a membrane or web or similar thin covering that partially or completely envelopes the body of the device. This covering has the advantage of preventing tissue from penetrating into the surgical area through the slots of the device. Preferably, the covering is transparent, allowing the surgeon to view the retracted tissues, thereby improving the safety of the procedure. This is a significant advantage over currently used retractors, which are most commonly made of metal and prevent view of the retracted tissues (thus bleeding or perforation may occur and not be noticed by the surgeon.). Exemplary materials for a transparent covering are polyurethane, silicone and other polymers and elastomers. An exemplary method for preparing the covering is as follows:

the surface is prepared in order to enable good adhesion between the polymer and the surface of the device by surface treatment or another primer; - the device is covered with a thin sheath (webbing) of the covering polymer by means of a dipping method.

The covering of the device may additionally be used as a means for detection of bleeding from the retracted tissues. This may be achieved by adding to the cover a material that will signalize and emphasize bleeding. Exemplary materials that can be added are fluoroscopic materials, or other coloring materials, that will visually shine when directly contacting with blood.

Referring again to FIG.l, The device 10 of the invention may contain several means for improving the view of the surgical are, and the access to the area. Thus, in one preferred embodiment the device of the present invention further comprises means for suction of fluids from the surgical area (not shown) . An exemplary suction means can be achieved by connecting one or more suction tubes alongside the longitudinal aspect of the device, to allow suction of fluids from the surgical area. In another preferred embodiment, the device further comprises means for illuminating the surgical area, for example by connecting fiber-optics alongside the device, or implementing LED light sources within the device.

Exemplary dimensions of the device of the invention are as follows. Longitudinal length is in the range of between about 2 cm to about 15 cm, preferably, about 5 cm. Horizontal length (diameter) , when in extended position, is in the range of between about 2 cm to about 20 cm, preferably, about 10 cm. When the device is to be used for endoscopic delivery (e.g. through a trocar) the diameter of the fully closed (i.e. collapsed) device will be approximately 5-8 mm.

The general depth or thickness of the material of the device is in the range of between about 0.01 mm (10 microns) to about 5.0 mm (5000 microns), preferably, about 0.3 mm (300 microns).

Referring again to the drawings, FIG. 2 is a schematic diagram illustrating a perspective view of an exemplary embodiment of the device of the invention in which there is more than one type of longitudinal rod. For example, longitudinal rods 50 have a different resiliency and a different ^' structure than longitudinal rods 60. In the exemplary embodiment of FIG. 2, longitudinal rods 60 are made of wire springs, wherein each wire is bent such that it contains one or more angled portions, each angled portion comprising either a rightward- directed or a leftward-directed apex.

Referring again to the drawings, FIG. 3A is a schematic diagram illustrating a perspective view of an exemplary embodiment of the device of the invention in which there is more than one type of horizontal rod. For example, horizontal rods 40 have a different resiliency and a different structure than horizontal rods 70.

In the exemplary embodiment of FIG. 3A, horizontal rods 70 are made of wire springs, wherein each wire is bent such that it contains one or more angled portions, each angled portion comprising either an inferiorly-directed or a superiorly- directed apex. FIG. 3B is a schematic diagram illustrating a perspective view of the exemplary embodiment of the device of FIG. 3A in use during an open surgical procedure. Opening 20 is the access plane through which the surgeon can insert the surgical tools into the surgical working space, within the device, and opening 30 is approximated to the tissue which is to be treated. In the example shown, the device is used for cranial surgery, showing the cut-down cranial bone 100.

FIG. 4 is a schematic diagram illustrating a perspective view of the exemplary embodiment of the device of FIG. 3A in use during endoscopic surgical procedure. Opening 20 is the access plane through which the surgeon can insert the surgical tools into . the surgical working space, within the device, and opening 30 is approximated to the tissue which is to be treated. In the example shown, the device is used for Laparoscopic surgery, showing gastrointestinal tissues 110 that are retracted by the device from the surgical area.

Referring again to the drawings, FIG. 5A is a schematic diagram illustrating a perspective view of an exemplary embodiment of the device of the invention in which the longitudinal length of the device can be altered in-situ, by manipulating the overlap between the different telescoping segments that are used to construct longitudinal rod 80. For example, longitudinal rods 80 can be inserted into the surgical area in a contracted state (maximal overlap between the elements) and enlarged in-situ by the surgeon by simple elongation (thus reducing the overlap between the elements) . A similar mechanism can be used for horizontal expansion of the device (not shown in the figures) .

FIG. 5B is a schematic diagram illustrating a perspective view of the exemplary embodiment of the device of FIG. 5A in use during a surgical procedure.

FIG. 6 is a photograph of an exemplary embodiment of the device of FIG. 3A. The device is approximated to a standard ballpoint pen, in order to illustrate exemplary dimensions. The exemplary device shown is made of two types of longitudinal rods, interconnected by horizontally oriented wires that enable shifting the device position from retracted to expanded (open) . There are several potential manufacturing approaches for manufacturing of the device of the invention, each approach having different steps explained here in more detail:

■ Manufacturing approach I: o Step 1. Rods and wires will be cut by laser or by chemical etching techniques . o Step 2. Once a 2D mesh- is formed, it will be bent on a jig to acquire the desired rounded shape, o Step 3. Rods will be connected to the rounded mesh by laser welding, o Step 4. The whole structure will be submitted to heat treatment to gain the desired flexibility, o Step 5. Final step before sterilization will be electropolished to achieve high quality, smooth surface area. ^■ Manufacturing approach II: o Step 1. Rods will be cut to desired length. o Step 2. Notches on the rods will be used to fix connection to wires. o Step 3. Wires will be laser welded to the rods, o Steps 4 & 5 as in approach I.

^■ Manufacturing approach III: o Step l.The device will be cut to its final shape from a tube with a diameter that matches the final product desired diameter. o Step 2. Heat treatment and electropolish as described above.

^■ Manufacturing approach IV: o The device will be made by weaving dense and flexible mesh wires. o Potential raw materials for this approach are stainless steel - 316L, 316LVM, PH17-4, Nitinol (nickel titanium alloy) , Polymer / plastic material cast over a metal wire mesh.

^■ Manufacturing approach V: o The device can be made of plastic, elastomeric or polymeric materials. In this case, an appropriate mould can be manufactured according to the required design. o For example, injection molding can be used, which involves heating & injecting plastic material under pressure into a closed metal mould tool. The molten plastic cools & hardens into the shape inside the mould tool, which then opens to allow the moldings to be removed.

Referring again to the drawings, FIG. 7A is a schematic diagram illustrating a perspective view of an exemplary embodiment of the device of the invention in which the length (diameter) of the access planes can be altered in-situ, by manipulating an external expansion mechanism attached to longitudinal rods 50. Longitudinal rods 50 and horizontal rods 40 of the device are shown. Connection elements 200 are used to connect pulling wires 210 to each proximal end of the longitudinal rods. Mechanism 220 can be used to employ forces on wires 210, thus enabling expansion or contraction of the device. For example, the device can be inserted into the surgical area in a contracted state and enlarged in-situ by¹ the surgeon by a simple maneuver of mechanism 220. FIG. 7B is a schematic diagram illustrating an enlarged view of an exemplary mechanism 220 for expanding and contracting the device, in which the forces are achieved by a helical screw mechanism.

FIG. 8 is another schematic diagram illustrating a view from above of a different embodiment of the device in which the length (diameter) of the access planes can be altered in-situ, by manipulating an external expansion mechanism. Connection elements 200 are used to connect pulling wires 210 to each proximal end of the longitudinal rods (shown here from above) . The mechanism exemplified here for expansion or contraction of the device is similar to a camera shutter (or diaphragm) , utilizing twisting motions for expansion and contraction of the device. FIG 8A illustrates a contracted state of the device, while FIG.8B illustrates an expanded state.

Referring again to the drawings, FIG. 9A is a schematic diagram illustrating a perspective view of another exemplary embodiment of the device of the invention, in which the device is constructed by one or more wires having an essentially tubular elastic form and in which the longitudinal length of the device can be altered in-situ, by releasing additional wire length through wire-grasper 230. FIG. 9B is a schematic diagram illustrating a perspective view of the exemplary embodiment of the device of FIG. 9A in use during a surgical procedure .

FIG. 1OA and 1OB illustrate perspective views of additional exemplary embodiments of the device of FIG. 9, in which the device is constructed by one or more wires having an essentially tubular elastic form, but in which the longitudinal length of the device is pre-determined during the manufacturing process, and not determined in-situ. Fig. 1OA illustrates a device with an essentially constant diameter, while FIG.1OB illustrates two devices with irregular diameters .

Referring again to the drawings, FIGS. HA and HB are schematic diagrams illustrating a two-dimensional planar view from above, and a perspective view, respectively, of an additional embodiment of the device 300 of the invention. In this exemplary embodiment the device is designed and constructed as an integral single elastic component, featuring a plurality of, for example four, elastic arms or extensions 310, longitudinally and radially extending from, for example, a single optional elastic lower basal section or ring formation 320, which is preferably self-expanding. The lower end regions of the elastic arms or extensions of the device are integral and continuous with each other, by way of optional elastic lower basal section or ring formation 320. The device is actually of conical geometry, shape, and, form, as particularly shown in FIG. HB, relative to a central longitudinal. FIG. HA particularly illustrates elastic as an inverse U shape, having a generally symmetrical pattern, however, other non-symmetrical and cut-out patterns may be designed. FIG. HB illustrates an optional covering, preferable transparent, which may be utilized in this design, similar to the covering previously described.

Referring again to the drawings, FIG. 12 is a schematic diagram illustrating a perspective view of an additional exemplary embodiment of the device of the invention in which the length (diameter) of the access planes can be altered in- situ, by manipulating the overlap between the elements of the device. FIG. 12A illustrates such a device that is constructed with one element 400, overlapping on itself. FIG. 12B illustrates such a device that is constructed with two elements 410 and 420, in which the overlap between the elements determines the horizontal diameter of the device. For example, the device can be inserted into the surgical area in a contracted state (maximal overlap between the elements) and enlarged in-situ by the surgeon by simple elongation (thus reducing the overlap between the elements) . The device can additionally utilize more than two elements (not shown in the figures). FIG. 12C is a schematic diagram illustrating a perspective view of the exemplary embodiment of the device of FIG. 12A and 12B, in a fully expanded state.

In a further preferred embodiment, shown in FIGS. 13A and 13B, the retractor of the present invention is constructed as an umbrella-shaped device 500. The device comprises a frame comprising a series of rod-like structures 510 which, in the fully open state, radiate outwards in a distal direction, thereby forming a structure having a conical or frusto-conical shape. The rods are affixed at their proximal ends to a common basal element 520, said element having a diameter that is sufficiently small to allow delivery of the device in its closed (collapsed) state through a trocar or other type of endoscopic port. In its open state, the intervals (e.g. 530) between adjacent rods provide space for the passage of working tools into and out from the working area (i.e. the surgical space contained within the internal space of the urnbrella-like frame). In one particularly preferred version of this embodiment, a portion of the frame, close to its distal end, is covered with a plastic or fabric membrane 540, the primary purpose of which is to prevent entry of adjacent organs and tissues (e.g. the intestinal loops 550) from entering into the surgical window.

The dimensions of this embodiment of the device, and the materials and methods used in its construction are the same as described hereinabove in connection with the other embodiments of the present invention.

In use, the device is inserted into the body cavity in its contracted or collapsed state, as shown in FIG. 13A, through a port 560, and allowed to expand (by virtue of the elastic forces inherent in the structure of the frame) within the surrounding tissues, as illustrated in FIG. 13B, thereby creating a discrete workspace (the surgical window) within the internal space that is bounded externally by the umbrella- shaped frame.

At the end of the procedure, the surgeon moves a metal ring (not shown) distally from its initial position (surrounding the rod-like structures at their proximal ends) to the distal end of the frame, thereby causing the umbrella-shaped device to adopt its closed (or collapsed) conformation. Alternatively, it is possible to close the device by having the operator pull it through the port entry (e.g. trocar) thereby forcing the umbrella-shaped device into its closed position. The device will then have a sufficiently small diameter to permit it to be withdrawn from the patient's body through the insertion port. The flowchart of Fig. 14 demonstrates the steps of an interventional procedure performed with the device of the invention. In this -example an endoscopic procedure is presented. The procedure starts with insertion of trocars to provide access for the surgical tools. The device of the invention can then be inserted through the trocars in a contracted state, delivered into the surgical area, and expanded to retract adjacent tissues and allow access to the surgical window. The surgeon then decides if a clear surgical window has been achieved. If not, the device of the invention may be re-contracted, and re-expanded in an improved location. After a clear view has been established, the surgical procedure may be performed, with maximal convenience and safety. At the end of the procedure, the device of the invention may be re-contracted and removed from the body, through a trocar.

While the invention has been described in conjunction with specific embodiments and examples thereof, it is evident that many . alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the present disclosure and claims.

Claims

1. A surgical retractor capable of being manipulated from a closed conformation to an open conformation and vice versa, wherein said retractor in its open conformation comprises a tube-like frame, such that the inner face of said frame defines the outer boundary of an internal space, and wherein said internal space is essentially eliminated when said retractor is in its closed conformation.

2. The surgical retractor according to claim 1, wherein the dimensions of said retractor in its closed conformation render it suitable for endoscopic delivery.

3. The surgical retractor according to claim 1, wherein the frame is covered with a membrane.

4. The surgical retractor according to claim 1, wherein said retractor is capable of self-expanding from a closed conformation to an open conformation as a result of outwardly directed elastic forces generated within the frame and/or membrane .

5. The surgical retractor according to claim 1, wherein said retractor is capable of being manipulated from a closed conformation to an open conformation and vice versa by means of manual deformation of the frame.

6. The surgical retractor according to claim 1, wherein the frame comprises a plurality of vertically and/or horizontally disposed elements.

7. The surgical retractor according to claim 6, wherein the frame comprises more than one type of vertically disposed element and/or more than one type of horizontally disposed element, each type being characterized by having a different resiliency.

8. The surgical retractor according to claim 7, wherein at least one type of vertically disposed element and/or at least one type of horizontally disposed element is a wire spring comprising a series of angled portions.

9. The surgical retractor according to claim 6, wherein one or more of the vertically and/or horizontally disposed elements are constructed from a plurality of telescopic segments.

10. The surgical retractor according to claim 1, wherein the frame is constructed from one or more materials selected from the group consisting of biocompatible metals, biocompatible metal alloys and biocompatible polymers.

11. The surgical retractor according to claim 10, wherein the biocompatible metal is selected from the group consisting of tungsten, platinum and titanium.

12. The surgical retractor according to claim 10, wherein the biocompatible metal alloy is selected from the group consisting of nitinol and stainless steel.

13. The surgical retractor according to claim 3, wherein the membrane is constructed from one or more biocompatible elastomers and/or polymers.

14. The surgical retractor according to claim 3, wherein the membrane is transparent.

15. The surgical retractor according to claim 6, further comprising a plurality of connection elements attached to the proximal end of the vertically disposed elements, wherein said connection elements are suitable for connecting pulling wires to said vertically disposed elements, such that said wires may be used to externally control the diameter of said retractor.

16. The surgical retractor according to claim 1, wherein the frame is a helix constructed from one or more elastically- deformable wires.

17. The surgical retractor according to claim 1, wherein the frame comprises a basal ring to which is attached a plurality of elastic arms extending longitudinally and radially therefrom.

18. The surgical retractor according to claim 17, wherein the elastic arms are constructed from wires formed into an inverted U shape.

19. The surgical retractor according to claim 1, wherein the frame comprises one or more elements that overlap in a circumferential plane, thereby permitting the diameter of said retractor to be altered by means of manipulating the degree of overlap between said overlapping elements.

20. The surgical retractor according to claim 6, wherein the frame has a polygonal cross-sectional shape, the sides of said polygonal shape being curved, and wherein said frame has a three dimensional form that is generally cylindrical.

21. The surgical retractor according to claim 6, wherein the frame has a circular cross-sectional shape, and wherein said frame comprises a plurality of longitudinally-disposed elements, and wherein the three dimensional form of said frame is frusto-conical .

22. A method for retracting tissues and/or organs during an open surgical procedure comprising the steps of: providing a surgical retractor according to any one of claims 1 - 21, inserting said retractor in its closed conformation through the external layers of the surgical incision, positioning said retractor at the desired operating location, manipulating said retractor from its closed conformation to an open conformation, such that the required tissues and/organs are displaced from the operating location, thereby providing clear visual and instrumental access to said operating location through the internal space of said retractor.

23. A method for retracting tissues and/or organs during an endoscopic surgical procedure comprising the steps of: insertion of one or more trocars through the external tissues overlying the operating site, providing a surgical retractor according to any one of claims 1 -21, delivering said retractor in its closed conformation through one of said trocars, positioning said retractor at the desired operating location, manipulating said retractor from its closed conformation to an open conformation, such that the required tissues and/organs are displaced from the operating location, thereby providing clear visual and instrumental access to said operating location through the internal space of said retractor.

24. The method according to claim 23, wherein the surgical procedure is a laparoscopic procedure.

25. The method according to claim 22 or claim 23, wherein the step of manipulating said retractor from its closed conformation to an open conformation comprises the release of a restraining element, thereby permitting the self-expansion of said retractor.

26. The method according to claim 22, wherein the step of manipulating said retractor from its closed conformation to an open conformation comprises the manual manipulation of the frame and/or membrane of said retractor,

27. The method according to claim 22 further comprising the steps of providing external anchoring means and using said means to anchor the retractor to tissues and/or organs located outside of the operating location.