Patent Description:
Other retraction devices according to the prior art include a pair of opposed, flexible rings where a first ring is placed on one side of a body wall, a second ring is placed on the opposite side of the body wall, and a thin film of waterproof material is stretched between the two rings. Some configurations of these devices can be difficult to place and may require the use of an assistant to attain proper tensioning.

Examples of known retraction devices are disclosed in patent documents, publication numbers <CIT>, <CIT> and <CIT>.

There remains a need for an easily placed and easily adjustable retraction device for maintaining retraction of an incision during a surgical procedure.

The present invention provides a surgical retraction device as recited in Claim <NUM> that may be inserted into a surgical incision in a first condition and subsequently expanded or reshaped to retract the incision.

These and other features of the invention will become more apparent with reference to the following drawings.

The drawings include illustrations helpful to the understanding of the invention and illustrations of retraction devices other than the retraction device in accordance with the present invention of <FIG>.

With reference to the drawings, <FIG> and <FIG> depict a hand assisted laparoscopic surgery <NUM> where an abdominal cavity <NUM> is created within an abdominal region <NUM> of a body by the introduction of a pressurized gas. A retraction device <NUM> is shown having a human hand <NUM> therethrough. To deploy the retraction device <NUM> within a patient's abdominal wall <NUM>, a surgical incision <NUM> is made through the abdominal wall and the retraction device is inserted and subsequently deployed to retract and enlarge the incision. The retraction device <NUM> may include a first, outer retention member, a second, inner retention member, and a membrane or sleeve coupled between the first retention member and the second retention member. The retraction device <NUM> may be shapeable <NUM> to facilitate placement through a small incision <NUM>. The retraction device <NUM> may be held by a hand in a low profile shape and condition <NUM> as it is inserted through the incision <NUM> and subsequently released so that the first, outer retention member and the second, inner retention member stretch the membrane between an outer surface of the body wall <NUM> and an inner surface <NUM> of the body wall.

Referring to <FIG>, a retraction device <NUM> is shown having a first, outer ring <NUM> and a second, inner ring <NUM> that are substantially concentric with each other. The first and second rings <NUM>, <NUM> may be semi-rigid and hinged along a common axis <NUM> that forms a first hinge <NUM> and a second hinge <NUM> that couple the first ring <NUM> and the second ring <NUM> together with the hinges being positioned substantially opposite each other on the circumference of the first and second rings. The retraction device <NUM> may transition from a first, concentric state (<FIG>) to a second, angular state (<FIG> and <FIG>) <NUM> where the first and second rings <NUM>, <NUM> are rotated about the axis <NUM> and form an angle between the planes of the first and second rings. The form of the retraction device <NUM> generally resembles a collapsible gyroscope. A gastight tubular membrane or sheath <NUM> (<FIG>) is coupled around the circumference of the first ring <NUM> and around the circumference of the second ring <NUM> such that when the first and second rings are in the second, angular state, the sheath is substantially cylindrical.

The first and second rings <NUM>, <NUM> are first compressed together to form a substantially concentric structure (<FIG>) where the wall of the membrane or sheath <NUM> is either not tensioned or only lightly tensioned. The compressed, concentric structure may be further streamlined by compressing the first and second rings <NUM>, <NUM> along the axis between the first and second hinges <NUM>, <NUM> to facilitate insertion of the retraction device <NUM> into the incision <NUM> in the body wall <NUM>. The further streamlining along the axis significantly elongates the retraction device <NUM> so that it can slide through a small incision <NUM>. Once the retraction device <NUM> has been inserted into the incision <NUM> to about the midpoint of the device, with the axis between the first and second hinges <NUM>, <NUM> being positioned substantially parallel to the abdominal wall <NUM> and parallel to the incision, the retraction device is unfolded and deployed so that the membrane or sleeve <NUM> is stretched within the incision <NUM>. As the two rings <NUM>, <NUM> of the device <NUM> are rotated about the axis <NUM> between the first and second hinges <NUM>, <NUM>, the membrane or sleeve <NUM> places retracting tension upon the tissue surrounding the membrane or sleeve. The first ring <NUM> and the second ring <NUM> now traverse the incision <NUM> and the extending portions of the rings abut the outer surface of the body wall <NUM> and the inner surface <NUM> of the body wall. This arrangement maintains the retraction device <NUM> in place within the incision <NUM> and also retracts and enlarges the incision.

The retraction device <NUM> includes means for maintaining the retraction device in the second, angular state <NUM>. Such maintaining means may include a ratchet mechanism that is positioned proximate at least one of the first and second hinges <NUM>, <NUM>. The ratchet mechanism may be positioned proximate each of the first and second hinges <NUM>, <NUM>. Alternatively, the maintaining means may include a valve structure mounted onto the retraction device external the body wall <NUM>. Other means for maintaining the retraction device <NUM> in the open, deployed condition include any suitable mechanical means that is well known in the art.

The first and second rings <NUM>, <NUM> may be made from a semi-rigid plastic material having sufficient strength to normally form a circle when no external forces are applied. Alternatively, the first and second rings <NUM>, <NUM> may include a metal or plastic reinforcing member placed within an elastomeric hollow or tubular structure forming the first and second rings. The rings <NUM>, <NUM> may also be made of a spring-like metal structure where the rings are formed from a flat metal spring or a round metal spring. Additionally, the rings <NUM>, <NUM> may be formed of a shapeable or malleable metallic material or composite. Alternatively, one of the first and second rings <NUM>, <NUM> may be made from a material having a first characteristic and the other one of the first and second rings may be made from a second material having a second characteristic. More particularly, the first ring <NUM> may be made of a more rigid material than the second ring <NUM>. For example, the first ring <NUM> may be made of a semi-rigid metal or plastic and the second ring <NUM> may be made of a plastic or other material less rigid than the material of which the first ring is made. When the first and second rings <NUM>, <NUM> are compressed together (<FIG>), the circumference of the second ring is collapsed to fit within the circumference of the first ring.

The membrane or sheath <NUM> may be formed from an elastomeric material or a thin, non-distensible material. The elastomeric materials may include silicone, polyisoprene, latex, vinyl and polyurethane. The non-elastic materials may include polyester, Mylar, polyethylene, and the like. These materials may be reinforced with a fabric or woven material to increase strength and durability.

Referring to <FIG>, a cross-ring wound retraction device <NUM> includes first and second retracting portions or rings <NUM>, <NUM> and a gastight, stretchable, tubular membrane, or sheath <NUM>, that may be tensioned between the retracting portions. The first and second retracting portions <NUM>, <NUM> are substantially concentric. The first and second retracting portions <NUM>, <NUM> may be hinged along a common axis <NUM>, thereby forming first and second hinges <NUM>, <NUM> that couple the first and second retracting portions together. The hinges <NUM>, <NUM> are positioned substantially opposite each other on the circumference of the first and second retracting portions <NUM>, <NUM>. The sheath <NUM> is coupled to each of the first and second retracting portions <NUM>, <NUM>.

The cross-ring retraction device <NUM> may be supplied in a first, relaxed state <NUM> (<FIG>) where the circumferential elastomeric sheath <NUM> is substantially non-tensioned or relaxed. In the first, relaxed state <NUM>, an angle is formed between the planes of the first and second rings <NUM>, <NUM> and there is a substantial through lumen <NUM> between the proximal end <NUM> and the distal end <NUM> of the retraction device <NUM>. To place the retraction device <NUM> in a second, tensioned state <NUM>, the profile of the retraction device may be reduced and deformed to facilitate placement through a small surgical incision <NUM> by rotating the retracting portions <NUM>, <NUM> toward each other across the proximal <NUM> and distal <NUM> opening planes such that the first and second rings become substantially concentric. The elastomeric sheath <NUM> is subsequently stretched longitudinally between the proximal end <NUM> and the distal end <NUM>, thereby placing the sheath in tension, with the opening of the lumen <NUM> being reduced and substantially occluded and the retraction device becoming substantially flat (see <FIG>). Additionally, once the retraction device <NUM> has been thus flattened, it may be streamlined further into an oval shape (<FIG>) by compressing the rings <NUM>, <NUM> along the axis <NUM> of the first and second hinges <NUM>, <NUM>. The retraction device <NUM>, in the flattened, streamlined condition (<FIG>) will fit through a much smaller incision <NUM> than is the case when the device is at rest <NUM>. The retraction device <NUM> may be urged through a surgical defect, such as an incision <NUM> (<FIG> and <FIG>), in a body wall <NUM> and subsequently allowed to assume the first relaxed state <NUM> in response to the release of the tension upon the elastomeric sheath <NUM>. The lumen <NUM>, including the proximal and distal openings <NUM>, <NUM> thereof, will open as the retraction device <NUM> assumes an open, deployed condition (<FIG>). The elastomeric sheath <NUM> forms a continuous, gastight barrier <NUM>, <NUM> between the lumen <NUM> of the retraction device <NUM> and the tissue of the retracted incision or defect <NUM>.

The elastomeric material of which the sheath <NUM> is made may be chosen to provide a range of retracting forces. For instance, a light weight, thin-walled, more elastic material yields a light retraction force in comparison to a thick-walled, less elastic material. Various diameters of retraction rings <NUM>, <NUM> may be combined with various qualities of elastomeric material to yield retraction devices that accommodate a wide range of body wall conditions or types. The present invention also contemplates the use of rigid or semi-rigid plastic or spring metal for the construction of the first and second retracting portions or rings <NUM>, <NUM>.

Referring to <FIG>, a retraction device <NUM> may include a distal continuous ring <NUM>, a first half ring <NUM> hinged to the distal continuous ring, a second half ring <NUM> hinged to the distal continuous ring, and a gastight, circumferential elastomeric sheath <NUM> coupled between the distal ring and the first and second half rings. The sheath <NUM> may also be coupled directly between the first and second half rings <NUM>, <NUM>.

One or both of the first and second half rings <NUM>, <NUM> may be positioned along the outer surface <NUM> of the distal continuous ring <NUM> and hinged along a common axis <NUM>, thereby forming a first hinge <NUM> and a second hinge <NUM> that couple the first and second half rings to each other and to the distal continuous ring with the hinges being positioned substantially opposite each other on the circumference of the distal continuous ring (<FIG>). Alternatively, one or both of the first and second half rings <NUM>, <NUM> may be positioned along the inner surface of the distal continuous ring <NUM> (<FIG>). In a first, neutral condition (<FIG>), the first half ring <NUM> is positioned on a first side <NUM> of the axis <NUM>, proximal the distal continuous ring <NUM>, and the second half ring <NUM> is positioned on a second, opposite side <NUM> of the axis proximal the distal continuous ring.

A first end portion <NUM> of the first half ring <NUM> and a first end portion <NUM> of the second half ring <NUM> overlap each other and a second end portion <NUM> of the first half ring and a second end portion <NUM> of the second half ring overlap each other. The first and second end portions <NUM>, <NUM> of the first half ring <NUM> may be positioned between the distal continuous ring <NUM> and the first and second end portions <NUM>, <NUM> of the second half ring <NUM>, respectively, so that the first and second half rings may rotate past each other. The retraction device may transition to a second, tensioned condition (<FIG>) by folding the first half ring <NUM> and the second half ring <NUM> flat and in alignment with the distal continuous ring <NUM>. In the second, tensioned condition, the first half ring, the second half ring and the distal continuous ring may be substantially concentric.

Preparing the retraction device <NUM> for insertion into an incision <NUM> in a body wall <NUM> includes transitioning the retraction device from the first, neutral condition to a second, tensioned condition. The transition from the first, neutral condition (<FIG>) to the second, tensioned condition (<FIG>) includes the first half ring <NUM> being rotated about the hinges <NUM>, <NUM> in a first direction <NUM> to a position on the second side <NUM> of the axis <NUM> and proximal the distal continuous ring <NUM>, thereby placing the portion of the sheath <NUM> that is coupled between the distal ring and the first half ring in tension (<FIG>). The second half ring <NUM> is rotated about the hinges <NUM>, <NUM> in a second, opposite direction <NUM> to a position on the first side <NUM> of the axis <NUM> and proximal the distal continuous ring <NUM>, thereby placing the portion of the sheath <NUM> that is coupled between the distal ring and the second half ring in tension (<FIG>). The first and second half rings <NUM>, <NUM> may be rotated about the hinges <NUM>, <NUM> further until they are substantially concentric with the distal continuous ring <NUM>. The retraction device <NUM> may be further streamlined by compressing the distal continuous ring <NUM> and the first and second half rings <NUM>, <NUM> along the axis <NUM> between the first and second hinges <NUM>, <NUM>, thereby elongating the retraction device <NUM> to facilitate insertion of the retraction device into the incision <NUM> more easily (<FIG> and <FIG>).

The retraction device <NUM> is inserted completely through the incision <NUM> and completely into the body cavity <NUM>. With the retraction device <NUM> positioned completely within the body cavity <NUM>, the second half ring <NUM> is rotated back in the first direction <NUM> and the first half ring <NUM> is rotated back in the second direction <NUM> until the first and second half rings are substantially perpendicular to the distal continuous ring <NUM>, substantially parallel to each other and proximal to the distal continuous ring (see <FIG>). The first and second half ring <NUM>, <NUM> are pulled proximally through the incision <NUM> until the distal continuous ring <NUM> abuts against the inner surface <NUM> of the body wall <NUM> and the first and second half ring are partially protruding from the incision. The first and second half ring <NUM>, <NUM> are released and allowed to assume a nearly neutral condition (<FIG>), thereby circumferentially retracting the incision <NUM>.

With reference to <FIG>, a retraction device <NUM> is shown having a first, distal retention ring <NUM>, a second, proximal retention ring <NUM>, a circumferential, tubular sheath <NUM> coupled to the first and second retention rings, a plurality of tensioning straps <NUM> and a proximal lock ring <NUM>. The distal retention ring <NUM> may be made from a shapeable or malleable material that may be deformed for easy insertion through a small body wall incision and subsequently allowed to assume a generally circular condition. The proximal retention ring <NUM> may be made from a material more rigid than the distal retention ring <NUM>. Each of the plurality of straps <NUM> is coupled to the distal retention ring <NUM> and extends proximally through a lumen of the sheath <NUM> and the proximal retention ring <NUM>. The proximal lock ring <NUM> is sized and configured to capture the straps <NUM> between an inner surface <NUM> of the proximal retention ring <NUM> and an outer surface <NUM> of the lock ring <NUM>. At least one of the inner surface <NUM> of the proximal retention ring <NUM> and the outer surface <NUM> of the lock ring <NUM> may be beveled. The invention contemplates the use of a strong, thin, non-elastic material, such as a fabric, for the construction of the straps <NUM>.

In use, the distal retention ring <NUM> is deformed and inserted into a body cavity <NUM> through an incision <NUM> in a body wall <NUM>. The proximal retention ring <NUM> is allowed to rest upon the outer surface of the body wall <NUM>. The lock ring <NUM> is placed within a lumen of the proximal retention ring <NUM> with the straps <NUM> exiting between the proximal retention ring and the lock ring. The straps <NUM> may be pulled proximally to achieve the appropriate tension and subsequent retraction of the incision. The lock ring <NUM> responds to the tension of the straps <NUM> by wedging against the inner surface <NUM> of the proximal retention ring <NUM> and substantially preventing the straps from slipping distally between the lock ring and the proximal retention ring. Removal of the retraction device <NUM> is accomplished by pulling at least one of the straps <NUM> proximally slightly to release the lock ring <NUM> from the proximal ring <NUM> and removing the lock ring to release the tension on the straps. With the tension of the straps <NUM> removed, the distal ring <NUM> may be removed from the body cavity <NUM> through the incision.

Referring to <FIG>, a wound retraction device <NUM> includes a proximal retention ring <NUM> and a plurality of shapeable, distally extending, retraction elements <NUM> coupled to the proximal retention ring and extending distally therefrom. The extending, retraction elements <NUM> are configured to transition from a first, low-profile, insertion condition <NUM> (<FIG>) to a second, expanded, high-profile retention condition <NUM> in which distal ends of the extending elements extend radially outwardly (<FIG>). The retention ring <NUM> may be sized and configured to hold the extending elements <NUM> in a generally perpendicular position to the plane of the retention ring. Alternatively, the extending elements <NUM> may extend radially inwardly to facilitate insertion or the retraction device <NUM> into the incision <NUM>. The extending elements <NUM> may be malleable so as to be shaped into a retracted state within an incision or they may be sized and configured to snap between a first, inwardly disposed condition to the second, outwardly disposed condition <NUM> in a détente relationship. A circumferential sheath may be associated with the retraction device <NUM> and positioned either between the extending elements <NUM> and adjacent tissue or within a lumen of the retraction device as a separate component.

In use, the extending elements <NUM> are inserted into a surgical incision <NUM> (<FIG> and <FIG>) in a body wall <NUM> and advanced distally until the proximal retention ring <NUM> is substantially abutted against an outer surface of the body wall. A surgeon may then insert his hand distally through the retention ring <NUM> and bend a distal portion <NUM> of each of the extending elements <NUM> radially outwardly such that the distal portions of the extending elements are placed against an inner surface <NUM> of the body wall <NUM>.

The extending elements <NUM> may be made of thin strips of sheet metal, such as spring steel, having a cupped or axially semicircular cross section resembling a steel tape measure or a slat of a venetian blind. Each of the extending elements <NUM> is oriented with the outer curve <NUM> of the semicircular cross section positioned radially outwardly. The extending elements <NUM> easily exist in the first, straight, insertion condition <NUM>. However, once bent inwardly on the outer semicircular surface <NUM>, the extensions transform to the second, curved, high-profile condition <NUM> for retention in the incision.

The extensions <NUM> may be made of a shape-memory material, such as nickel-titanium alloy. At a first temperature, the extending elements <NUM> made of nickel-titanium alloy may be in a first, substantially straight condition <NUM>, and when placed in an environment having a second, higher temperature, the extensions transform to a second, curved condition <NUM> with the distal ends of the extending elements extending radially outwardly. For example, the device <NUM> may be held in a relatively cold environment, such as in ice water, and subsequently inserted into a warm environment where the temperature is higher, such as in a live body. The shape of nickel-titanium alloy extending elements <NUM> changes according to a preset condition.

Referring to <FIG>, the wound retraction device <NUM> may include a plurality of pull wires <NUM> with each pull wire corresponding with a respective extending element <NUM>. Each of the pull wires <NUM> is coupled to a distal portion <NUM> of a respective extending element <NUM> and configured such that when the pull wire is pulled proximally, the distal portion of the respective extending element deflects radially outwardly. Each pull wire <NUM> forces the distal portion <NUM> of the respective extending element <NUM> to exhibit a shape that is determined by the tension of the pull wire. The pull wires <NUM> may be deployed collectively or individually to bend the extending elements <NUM>. Each of the pull wires <NUM> may traverse through a pull wire retainer <NUM> that is positioned along the length of the outer surface <NUM> of a respective extending element <NUM>. Each pull wire retainer <NUM> may include at least one eyelet <NUM>, tube <NUM> or other similarly functioning device. The pull wire retainers <NUM> function to limit the distance that the pull wires <NUM> deviate from the outer surface <NUM> of the extending elements <NUM> when the pull wires are pulled proximally to deflect the distal portions <NUM> of the extending elements. The pull wire retainers <NUM> may be longitudinally aligned along the length of the outer surface <NUM> of the extending element <NUM>.

Referring to <FIG>, a wound retraction device <NUM> includes an outer ring <NUM> having a substantially annular shape with an adjustable circumference and a substantially tubular structure <NUM> extending distally from the outer ring. The outer ring <NUM> is divided into a plurality of curved ring segments <NUM> with adjacent curved ring segments being coupled together by means for adjusting the circumference, such as a ratcheting mechanism <NUM>, to form the annular shape. Each of the curved ring segments <NUM> includes a first, proximal side <NUM>, a second, distal side <NUM>, a first end <NUM> about the circumference of the outer ring <NUM> and a second end <NUM> about the circumference of the outer ring. The curved ring segments <NUM> may be flexible to maintain a substantially circumferential shape of the outer ring <NUM> as the diameter of the outer ring is adjusted.

The ratcheting mechanism <NUM> may include a groove <NUM> in the proximal surface <NUM> of each of the curved ring segments <NUM>. The groove <NUM> substantially follows the curve of the curved ring segment <NUM> and is opened to the first end <NUM> of the curved ring segment. The groove <NUM> includes a plurality of ratchet teeth <NUM> positioned, for example, on a first, outer curved surface <NUM> of the groove. Alternatively, the ratchet teeth <NUM> may be positioned on a second, inner curved surface <NUM> of the groove <NUM> or on the distal surface <NUM> of the groove. The groove <NUM> may also include a retention channel <NUM> in at least one of the outer and inner curved surfaces <NUM>, <NUM> of the groove.

Each of the curved ring segments <NUM> also includes a flexible, elongate protuberance <NUM> extending from the second end <NUM> of the curved ring segment adapted to mate with the groove <NUM> in an adjacent curved ring segment. The elongate protuberance <NUM> includes at least one ratchet tooth <NUM> that interacts with the ratchet teeth <NUM> in the groove <NUM> of the curved ring segment <NUM> adjacent the elongate protuberance. Forming the outer ring <NUM> includes aligning the curved ring segments <NUM> together circumferentially with the first end <NUM> of each of the curved ring segments positioned adjacent the second end <NUM> of an adjacent curved ring segment and inserting the elongate protuberance <NUM> of each of the curved ring segments into the groove <NUM> of the other adjacent curved ring segment such that the at least one ratchet tooth <NUM> on the elongate protuberance interacts with the ratchet teeth <NUM> in the groove.

To substantially prevent the elongate protuberance <NUM> of one curved ring segment <NUM> from inadvertently slipping out of the groove <NUM> of the adjacent curved ring segment, the elongate protuberance may include a lip <NUM> (<FIG>) extending longitudinally along the length of the elongate protuberance and adapted to interact with the retention channel <NUM> in the groove of the adjacent curved ring segment. The diameter of the outer ring <NUM> is adjusted by inserting and retracting the elongate protuberances <NUM> within the grooves <NUM> of the adjacent curved ring segments <NUM>. The diameter of the outer ring <NUM> is increased as the curved ring segments <NUM> are moved further apart and the diameter is decreased as the curved ring segments are moved closer together.

As with the outer ring <NUM>, the substantially tubular structure <NUM> is also divided into a plurality of elongate tube segments <NUM> with each of the tube segments being coupled to a respective curved ring segment <NUM> and extending distally from the respective curved ring segment. The tube segments <NUM> may each extend circumferentially between the first end <NUM> and the second end <NUM> of the curved ring segment <NUM> to which the respective tube segment is coupled (<FIG>) such that there is no overlap between adjacent tube segments. Alternatively, each of the tube segments <NUM> may extend circumferentially beyond at least one of the first and second ends <NUM>, <NUM> of the curved ring segment to which the respective tube segment is coupled (<FIG>) such that adjacent tube segments may overlap each other. The profile of the tube segments <NUM> may substantially follow the curve of the curved ring segment <NUM> to which the respective tube segment is coupled. The tube segments <NUM> may be flexible so as to follow any change of the curve of the curved ring segments <NUM> to which the respective tube segments are coupled. The tube segments <NUM> may be made of a biocompatible material, such as a metallic or polymeric material.

Referring to <FIG>, the retraction ring <NUM> may include an inner ring <NUM> that is substantially opposite to the outer ring <NUM> to maintain the diameter of the tubular structure <NUM> at the distal end <NUM> of the tubular structure substantially the same as the diameter at the proximal end <NUM> of the tubular structure. The inner ring <NUM> includes the ratcheting mechanism <NUM>, but with the groove <NUM> positioned on the distal surface of the curved ring segments <NUM>. In use, with both the outer ring <NUM> and the inner ring <NUM> retracted to their smallest respective diameters, the distal end <NUM> of the wound retraction device <NUM>, including the inner ring, may be inserted through a small incision <NUM> (<FIG> and <FIG>) in a body wall <NUM> and into a body cavity <NUM>. The inner ring <NUM> may be expanded to a larger diameter to deploy the inner ring in the form of a distal retention member. With the inner ring <NUM> deployed, the outer ring <NUM> may be adjusted to a larger diameter to provide tension upon the tube segments <NUM>, thereby providing circumferential retraction of the incision.

For retraction rings <NUM> that do not include the inner ring <NUM>, the distal ends <NUM> of the tube segments <NUM> may be inserted into the incision <NUM> and into the body cavity <NUM>. The outer ring <NUM> may be adjusted to a larger diameter to provide tension upon the tube segments <NUM>, thereby providing circumferential retraction of the incision <NUM>. The tube segments <NUM> are sufficiently strong to maintain retraction of the incision <NUM> without substantially deflecting the tube sections.

Referring to <FIG> a circumferential surgical retraction device <NUM>, in accordance with the present invention, includes a first, substantially annular, outer ring <NUM> and a second, substantially annular, inner ring <NUM>. The first and second rings <NUM>, <NUM> are separated by a substantially gastight cylindrical sleeve <NUM>. The first and second rings <NUM>, <NUM> are made of a substantially flexible material, such as a polymeric material, and are reinforced with a first and second biasing member <NUM>, <NUM>, respectively, such as a spring-like core positioned in each of the first and second rings, that biases the first and second rings radially outwardly. Biasing the first and second rings <NUM>, <NUM> radially outwardly subsequently biases the retraction device <NUM> toward a shorter axial length. The cylindrical sleeve <NUM> is coupled to the first and second rings <NUM>, <NUM>. The cylindrical sleeve <NUM> includes a bellows <NUM>, that allow the cylindrical sleeve to transition between a first, axially compressed state (<FIG>) and a second, axially extended state (<FIG>).

With the retraction device <NUM> in the first, axially compressed state (<FIG>), the retraction device may be further compressed radially at opposing points along the inner and outer rings <NUM>, <NUM> to transform the retraction device into a low profile, elongate, oval shape to facilitate insertion into an incision <NUM> (<FIG> and <FIG>). The retraction device <NUM> is advanced through the incision <NUM> until the inner ring <NUM> is completely within the body cavity <NUM>. The radial compression is released from the inner ring <NUM> and the inner ring is permitted to assume its substantially circular configuration. The outer ring <NUM> is pulled proximally through the incision, thereby pulling the inner ring <NUM> into sealing contact with the inner surface <NUM> of the body wall <NUM> and stretching the bellows <NUM> of the cylindrical sleeve <NUM>. The outer ring <NUM> is pulled proximally until the outer ring is outside the incision <NUM> and the retraction device is in the second, axially extended state (<FIG>). The first biasing member <NUM> in the outer ring <NUM> biases the outer ring radially outward and into sealing contact with the outer surface of the body wall <NUM>. With the biasing member <NUM>, <NUM> in each of the outer and inner rings <NUM>, <NUM> biasing the rings radially outward, the cylindrical sleeve <NUM> is placed in tension and retracts the incision <NUM>. Following the surgical procedure, removal of the retraction device <NUM> is accomplished by reaching into the body cavity <NUM> and pulling the inner ring <NUM> proximally through the incision <NUM>, thereby removing the cylindrical sleeve <NUM> from the incision.

Claim 1:
A circumferential surgical retraction device comprising:
a first, outer ring (<NUM>) being made of flexible material;
a second, inner ring (<NUM>) being made of flexible material;
a cylindrical sleeve (<NUM>) coupled to the first and second rings (<NUM>, <NUM>);
a first biasing member (<NUM>) associated with the first, outer ring (<NUM>), the first biasing member (<NUM>) biasing the first ring (<NUM>) radially outwardly; and
a second biasing member (<NUM>) associated with the second, inner ring (<NUM>), the second biasing member (<NUM>) biasing the second ring (<NUM>) radially outwardly,
wherein the first and second biasing members (<NUM>, <NUM>) place the cylindrical sleeve (<NUM>) in tension to retract an incision, the first biasing member (<NUM>) includes a spring-like core embedded within the flexible material of the first, outer ring (<NUM>), the second biasing member (<NUM>) includes a spring-like core embedded within the flexible material of the second, inner ring (<NUM>), and the cylindrical sleeve (<NUM>) comprises bellows (<NUM>) arranged to transition the cylindrical sleeve (<NUM>) between a first, axially compressed state and a second, axially extended state, the cylindrical sleeve (<NUM>) being in the second axially extended state with the first, outer ring (<NUM>) and the second, inner ring (<NUM>) radially biased outwardly.