PATENT ABSTRACT
A minimally invasive surgical procedure is disclosed which includes the steps forming a fold of tissue, extending one or more needles through the fold of tissue, deploying a tissue fastener from an interior lumen of each of the needles, and retracting each of the needles from the fold of tissue such that the tissue fasteners remain deployed in the fold of tissue.

PATENT DESCRIPTION
This application claims priority from provisional application Ser. No. 60/342,540 filed Dec. 20, 2001, the entire content of which are incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The subject invention is directed to a minimally invasive surgical procedure, and more particularly, to an endoscopic surgical procedure for treating gastroesophageal reflux disease, and apparatus for performing the procedure. 
   2. Background of the Related Art 
   Gastroesophageal reflux disease (GERD) is one of the most common upper-gastrointestinal disorders in the western world, with a prevalence of approximately 360 cases per 100,000 population per year. Approximately 25 will eventually have recurrent, progressive disease and are candidates to undergo anti-reflux surgical procedures for effective long term therapy. 
   GERD is a condition in which acids surge upward from the stomach into the esophagus. Backflow of acid into the esophagus makes it raw, red and inflamed, producing the condition known as esophagitis; it also causes the painful, burning sensation behind the breastbone known as heartburn. Backflow or reflux of acid can occur when the sphincter or band muscle at the lower end of the esophagus fails to stay closed. This sphincter is called the lower esophageal sphincter (LES). The LES acts as a valve to the stomach, remaining closed until the action of swallowing forces the valve open to allow food to pass from the esophagus to the stomach. Normally the valve closes immediately after swallowing to prevent stomach contents from surging upward. When the LES fails to provide that closure, stomach acids reflux back into the esophagus, causing heartburn. 
   The general approach for corrective surgery involves creating a new valve or tightening the existing valve. This procedure is known as “fundoplication” and is used to prevent the back flow of stomach acids into the esophagus. Various fundoplication procedures have been developed to correct GERD and are known as Nissen fundoplication, Belsey Mark IV repair, Hill repair and Dor repair. Each surgical procedure has its own unique attributes; however, each requires an invasive surgical procedure, whereby the individual must endure trauma to the thoracic cavity. The individual remains hospitalized after the procedure for about six to ten days. 
   The Nissen fundoplication technique involves enveloping the lower esophagus with the gastric fundus by suturing the anterior and posterior fundal folds about the esophagus. Modifications of this procedure include narrowing of the esophageal hiatus posterior to the esophagus, anchoring of the fundoplication to the preaortic fascia and surgical division of the vegus nerve. The degree of the fundal wrap can be modified to incompletely encircle the esophageal tube to avoid gas float syndrome and has also been modified to include a loose wrap. Similarly, the Belsey Mark IV repair, Hill repair and Dor repair are directed to modifications for encirclement of the esophageal tube by fascia. 
   Complications of these fundoplication procedures include the inability to belch or vomit, dysphagia, gastric ulcer, impaired gastric emptying and slippage of the repair that may foil the best surgical results. Therefore, the fundoplication procedures have been modified to adjust the length and tension of the wrap, include or exclude esophageal muscle in the sutures and leaving the vagus nerves in or out of the encirclement. 
   A relatively new fundoplication technique is known as Nissen fundoplication laparoscopy. In contrast to the traditional Nissen fundoplication procedure, which requires a 6 to 10 inch incision and a 6 to 10 day hospital stay with up to 8 weeks of recovery at home, the laparoscopy technique is performed through small openings about the abdominal cavity and most patients tend to leave the hospital in two days and can return to work and other activities within a week or two. Despite the benefits of less invasive laparoscopic fundoplication procedures, there is still a need for a minimally invasive corrective treatment for GERD that can be performed on an out-patient basis. 
   SUMMARY OF THE INVENTION 
   The subject invention is directed to a new and useful minimally invasive surgical procedure for treating Gastroesophageal reflux disease by reducing the diameter of the esophagus proximate to the lower esophageal sphincter, and to an endoscopic surgical apparatus for performing the procedure. The method includes the steps of forming a fold of esophageal tissue proximate to the lower esophageal sphincter, and extending at least one needle through the fold of esophageal tissue. Each of the needles has an interior lumen containing a tissue fastener. The method further includes the steps of ejecting a distal portion of the tissue fastener from the interior lumen of each needle such that the distal portion of each tissue fastener is disposed against a distal surface of the fold of esophageal tissue, and retracting each needle from the fold of esophageal tissue such that a proximal portion of each tissue fastener is deployed from the interior lumen of each needle and is disposed against a proximal surface of the fold of esophageal tissue. 
   The method further comprises the step of providing an endoscopic device having a an interior lumen for supporting the needles in a manner that permits the reciprocal movement thereof, and a tissue reception cavity for receiving the fold of esophageal tissue. The method includes guiding the endoscopic device through the esophagus to a location wherein the tissue reception cavity is disposed proximate to the lower esophageal sphincter. Thus, the step of forming the fold of esophageal tissue includes the step of drawing esophageal tissue into the tissue reception cavity of the endoscopic device. This may be accomplished using suction or with a tissue grasping device. 
   Preferably, a tissue fastener of shape memory alloy or a similar bio-compatible material having memory characteristics is provided within the interior lumen of each needle in a generally elongate orientation. The step of ejecting a tissue fastener from the interior lumen of a needle includes permitting the distal portion of the tissue fastener to move to a normally unstressed condition (at body temperature) wherein the distal portion of the tissue fastener is in a curved or coiled orientation. The step of retracing the needle from the fold of esophageal tissue includes permitting the proximal portion of the tissue fastener to move to a normally unstressed condition (at body temperature) wherein the proximal portion of the tissue fastener is in a curved or coiled orientation. It is envisioned that the needles may be extended through the fold of esophageal tissue simultaneously or in seriatim. Similarly, the tissue fasteners may be ejected from the needles simultaneously or in seriatim. After the fasteners have been ejected from the needles, the fold of esophageal tissue is released from the tissue reception cavity, and the endoscopic device is withdrawn from the esophagus. 
   The subject invention is further directed to an endoscopic surgical apparatus for performing the method summarized above. The apparatus includes an elongated tubular body having opposed proximal and distal end portions and an interior lumen extending therethrough. An endoscope may be housed within the interior lumen of the tubular body. Preferably, one or more needles are disposed within the elongated tubular body and are mounted for reciprocal movement therein between a retracted position and a protracted position. Depending upon the configuration and orientation of the needles within the tubular body, it is envisioned that the reciprocal movement thereof may be either longitudinal, rotational or helical. Each of the needles has an interior lumen extending therethrough. A tissue fastener is disposed within the interior lumen of each needle. The fasteners are configured for movement between an initially straight position within the interior lumen of a needle and a subsequently coiled or curved position ejected from the interior lumen of a needle. 
   A mechanism is provided for effectuating reciprocal movement of the needle within the interior bore of the elongated tubular body, and a mechanism if provided for ejecting the tissue fasteners from the interior lumen of the needles. Preferably, a tissue receiving window is formed within the distal end portion of the elongated tubular body for receiving a fold of esophageal tissue. Thus, the retracted position of the needle is proximal to or, in some instances lateral to the tissue receiving window and the protracted position of the needle is distal of the tissue receiving window. 
   These and other aspects of the subject invention and the method of using the same will become more readily apparent to those having ordinary skill in the art from the following detailed description of the invention taken in conjunction with the drawings described hereinbelow. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     So that those having ordinary skill in the art to which the subject invention appertains will more readily understand how to make and use the surgical apparatus disclosed herein, preferred embodiments thereof will be described in detail hereinbelow with reference to the drawings, wherein: 
       FIG. 1  is a perspective view of a surgical apparatus constructed in accordance with a preferred embodiment of the subject invention; 
       FIG. 1   a  is an enlarged localized perspective view, in partial cross-section, of the distal portion of the surgical apparatus of  FIG. 1 , with parts separated for ease of illustration, wherein the apparatus includes a plurality of elongated needles mounted for reciprocal longitudinal movement relative to the longitudinal axis of the apparatus; 
       FIG. 2  is a perspective view of another surgical apparatus constructed in accordance with a preferred embodiment of the subject invention; 
       FIG. 2   a  is an enlarged localized perspective view of the distal portion of the surgical apparatus of  FIG. 2 , with parts separated for ease of illustration, wherein the apparatus includes a plurality of curved needles mounted for reciprocal rotational movement relative to the longitudinal axis of the apparatus; 
       FIG. 3  is a perspective view of another surgical apparatus constructed in accordance with a preferred embodiment of the subject invention; 
       FIG. 3   a  is an enlarged localized perspective view of the distal portion of the surgical apparatus of  FIG. 3 , with parts separated for ease of illustration, wherein the apparatus includes a plurality of partially helical needles mounted for reciprocal helical movement relative to the longitudinal axis of the apparatus; 
       FIG. 4  is a side elevational view of the distal portion of the surgical apparatus of  FIG. 1  illustrating the formation of a fold of esophageal tissue proximate to the lower esophageal sphincter during a treatment procedure; 
       FIG. 5  is a side elevational view the distal portion of the surgical apparatus of  FIG. 1  illustrating the extension of a needle through the fold of esophageal tissue, wherein the interior lumen of the needle contains a tissue fastener; 
       FIG. 6  is a side elevational view the distal portion of the surgical apparatus of  FIG. 1  illustrating the ejection of a distal portion of the tissue fastener from the interior lumen of the needle such that the distal portion of the tissue fastener is disposed against a distal surface of the fold of esophageal tissue; 
       FIG. 6   a  is an enlarged localized view of the needle shown in  FIG. 6  illustrating the ejection of the fastener from the interior lumen of the needle by the needle pusher; 
       FIG. 7  is a side elevational view of the distal portion of the surgical apparatus of  FIG. 1  illustrating the retraction of the needle from the fold of esophageal tissue such that a proximal portion of tissue fastener is deployed from the interior lumen of the needle and is disposed against a proximal surface of the fold of esophageal tissue; and 
       FIG. 7   a  is an enlarged localized view of the needle shown in  FIG. 7  illustrating the retraction of the needle from the fold of tissue. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   Referring now to the drawings wherein like reference numerals identify similar structural features of the apparatus disclosed herein, there is illustrated in  FIG. 1  an endoscopic surgical apparatus constructed in accordance with a preferred embodiment of the subject invention and designated generally by reference numeral  10 . 
   Referring to  FIG. 1  in conjunction with  FIG. 1   a , endoscopic surgical apparatus  10  includes an elongated flexible tubular body  12  having opposed proximal and distal end portions  14 ,  16  and an interior lumen  18  extending therethrough. Elongated flexible needles  20  with tapered leading edges are disposed within the elongated tubular body  12  and are mounted for reciprocal longitudinal movement therein between a retracted position and a protracted position. More particularly, the elongated needles  20  are supported in circumferentially spaced relationship within tubular body  12  by a needle block  25 . Needle block  25  is mounted at the distal end of a tubular drive shaft  27  which is adapted for reciprocal axial movement within tubular body  12 . 
   Each elongated needle  20  has an interior lumen  22  extending therethrough. A tissue fastener  24  formed of a shape memory metal alloy, such as a nickel-titanium alloy, is disposed within the interior lumen of each needle  20 . The tissue fastener  24  is configured for movement between an initially straight position within the interior lumen of the elongated needle and a subsequently coiled position ejected from the interior lumen of the elongated needle. In the straight position, and in the coiled position, opposed end portions  24   a ,  24   b  of the fastener  24  have a generally curved configuration. In  FIG. 2   a , the end portion  24   a  of fastener  24  is shown in the coiled position, while the opposed end portion  24   b  is shown in a transitional state between the initially straight position and the subsequently coiled or curved position. 
   An elongated push rod  26  extends through the interior lumen  22  of each elongated needle  20  for ejecting at least a portion of the tissue fastener  24  from the interior lumen  22  of the elongated needle  20 . Each push rod  26  is supported in circumferentially spaced relationship by a push rod block  30 . Push rod block  30  is mounted at the distal end of a tubular drive shaft  29  which is mounted coaxial with drive shaft  27 . Drive shaft  29  is adapted and configured for reciprocal axial motion within tubular body  12 . 
   As best seen in  FIG. 1 , surgical apparatus  10  further includes an actuation mechanism  35  operatively associated with a proximal portion  14  of the elongate body  12 . Actuation mechanism  35  is adapted and configured to effectuate reciprocal longitudinal movement of the drive shaft  27  associated with needle block  25  and the drive shaft  29  associated with push rod block  30 . It is envisioned that actuation mechanism  35  can take the form of a mechanical actuator, a pneumatic actuator, a hydraulic actuator or an electrical actuator which transmits force to the drive shafts  27 ,  29  through conventional mechanisms, such as cooperative linkages, gear trains or combinations thereof. It is also envisioned that the fasteners can be fired in a proximal direction. 
   Surgical apparatus  10  further includes a generally U-shaped or concave tissue receiving window  32  formed within the distal end portion of the elongated tubular body  12 . In the retracted position, the elongated needles  20  are proximal of the tissue receiving window  32  and in the protracted position, the elongated needles  22  travel to a position that is distal to the tissue receiving window  32 . 
   As illustrated in  FIG. 1   a , as an option, the surgical apparatus  10  of the subject invention could be provided with an angioplasty balloon  40  that would be accommodated within an elongated lateral lumen  42 . It is envisioned that angioplasty balloon  40  could be extended from the distal end of tubular body  12  and used as a dilator to increase the esophageal diameter prior to placement of the fasteners  24 . 
   Referring to  FIGS. 2 and 2   a , there is illustrated another surgical apparatus  110  constructed in accordance with a preferred embodiment of the subject invention that includes an elongated body  112  having opposed proximal and distal end portions  114  and  116 , and an interior lumen  118  extending therethrough. The distal end portion  116  has a tissue receiving window  132  formed therein and the proximal portion  114  has an actuator handle  135  operatively associated therewith. 
   As best seen in  FIG. 2   a , surgical apparatus  110  includes a plurality of curved needles  120  each supporting a surgical fasteners  124  in the interior lumen  122  thereof. The curved needles  120  are supported in axially spaced relationship on a needle block  125  that is mounted for reciprocal rotational movement within body portion  112 . A plurality of curved push rods  126  are supported on a push rod block  130  adjacent needle block  125 . Each push rod  126  is configured to eject at least a portion of a tissue fastener  124  from the interior lumen  122  of a needle  120  upon actuation of handle  135 . Those skilled in the art will readily appreciate that conventional mechanisms such as drive screws or drive shafts may be employed to transmit rotational motion from actuation handle  135  to needle block  125  and push rod block  130 . 
   Referring to  FIGS. 3 and 3   a , there is illustrated another surgical apparatus  210  constructed in accordance with a preferred embodiment of the subject invention that includes an elongated body  212  having opposed proximal and distal end portions  214  and  216 , and an interior lumen  218 . A tissue receiving window  232  is formed in the distal end portion  216  and an actuator handle  235  is operatively associated with the proximal potion  214 . As best seen in  FIG. 3   a , surgical apparatus  210  differs from surgical apparatus  110  in that it includes a plurality of partially helical needles  220  that are mounted for reciprocal helical movement within body portion  212  relative to the longitudinal axis of body portion  212 . 
   While not shown in  FIG. 3   a , a surgical fastener formed from shape memory alloy is supported with the interior lumen  222  of each needle  220  and is configured for deployment in the manner described above with respect to apparatus  110 . Those skilled in the art will readily appreciate that conventional mechanisms such as drive screws or drive shafts may be employed to transmit helical motion from actuation handle  235  to the needle block and push rod block operatively associated with curved needles  220 . 
   The subject invention is also directed to a method of treating gastroesophageal reflux disease using a surgical apparatus constructed in accordance a preferred embodiment of the subject invention, such as, for example, surgical apparatus  10 . Initially, during a surgical procedure, the elongated body  12  of surgical apparatus  10  is extended through the esophagus such that tissue receiving window  32  is positioned in a location that is proximate to the esophageal sphincter. Next, as shown in  FIG. 4 , a fold of esophageal tissue is drawn into the tissue receiving window  32 . This is preferably done under visual observation using the flexible endoscope  50  extended through the interior lumen  18  of body  12 , and is preferably accomplished by suction or using a tissue grasping device such as tissue grasper  45 . 
   Thereafter, one or more needles  20  are extended through the fold of esophageal tissue, as shown in  FIG. 5 . At such a time, the distal portion  24   a  of the tissue fastener  24  in each needle  20  is ejected from the interior lumen  22  of each needle  20  by push rod  26  such that the distal portion  24   a  of each tissue fastener  24  is disposed against a distal surface of the fold of esophageal tissue in a curved condition, as shown in  FIGS. 6 and 6   a . Then, as shown in  FIGS. 7 and 7   a , needles  20  are retracted from the fold of esophageal tissue such that the proximal portion  24   b  of each tissue fastener  24  is deployed from the interior lumen  22  of needle  20  and is disposed against a proximal surface of the fold of esophageal tissue. 
   In instances wherein more than one needle is employed, the needles may be extended through the fold of esophageal tissue either simultaneously or in seriatim by staging the needles at different positions relative to one another. Similarly, the tissue fasteners may be ejected from the needles simultaneously or in seriatim by staging the push rods at different positions relative to one another. After the needles have been retracted, the fold of esophageal tissue is released from the tissue reception cavity. 
   Once the fasteners  24  have been deployed, the fold of tissue with which they are associated will undergo repetitive movement during peristalsis. Since the ends of the fasteners are curved and flexible, they will advantageously comply with the fold of tissue as it moves. This flexibility also accommodates belching and vomiting. Furthermore, the flexible configuration of the fasteners facilitates the easy removal thereof from the fold of tissue should it become necessary to reverse the procedure. This may be done with a grasping device, such as that which is illustrated in  FIG. 4 . 
   Preferably, the steps of the subject invention are performed under vision using an endoscope which may be provided integral with surgical device  10 . Alternatively, the treatment method of the subject invention may be performed using either ultrasound, fluoroscopy or magnetic resonance imaging. 
   It is also envisioned and well within the scope of the subject invention that the surgical apparatus  10  and the method of using the same can be employed to reduce the volume of a patients stomach. In such a procedure, gastric tissue would be fastened using the apparatus of the subject invention. Since the ends of the fasteners utilized in this procedure are curved and flexible, they will comply or unfurl with the fold of tissue as the stomach expands with the intake of food. 
   Although the apparatus and method of the subject invention have been described with respect to preferred embodiments, those skilled in the art will readily appreciate that changes and modifications may be made thereto without departing from the spirit and scope of the present invention as defined by the appended claims.