Patent Publication Number: US-2003225432-A1

Title: Soft tissue retraction device for an endoscopic instrument

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001] The present invention relates to the field of endoscopic instruments. More specifically, the present invention relates to methods and devices for creating a working space in a body cavity within which endoscopic tools can access a target site.  
       BACKGROUND OF THE INVENTION  
       [0002] Many thoracic surgical procedures are performed for heart and lung disease, muscle and nerve disorders, ulcers and other serious illnesses. Although surgery may be the best, or only way to treat the disease, patients can sometimes face a long and difficult recovery because traditional “open” thoracic surgery is highly invasive. In an open thoracic surgery, known as a thoracotomy, surgeons must make a long incision through chest muscles and then cut and spread the patient&#39;s ribs to reach the diseased area. As a result, patients may spend up to a week in the hospital and up to four to six weeks of recovery at home.  
       [0003] The development of endoscopic video capability and instrumentation has resulted in the application of diagnostic and therapeutic thoracoscopy, also known as video-assisted thoracic surgery (VATS), to many disease processes encountered in thoracic medicine. VATS is a technique in which small diameter instruments such as cameras, graspers, forceps, retractors, dissectors, clamps, and so forth are inserted through small openings in the body to perform surgical procedures within the thoracic cavity. By utilizing a VATS procedure for exploring, diagnosing, and treating disease processes within the thoracic cavity, the pain, morbidity, and long recovery duration of more invasive procedures, such as the traditional large incision thoracotomy can often be avoided.  
       [0004] VATS procedures typically require double-lumen endotracheal intubation and single-lung ventilation. Working space in which to maneuver surgically in the chest is created by ventilating the opposite lung through the double-lumen endotracheal tube and allowing collapse of the affected lung after creation of a small intercostal incision. Collapse of the affected lung enables improved visibility of the lung, as well as virtually all the major structures in the chest cavity, to aid in exploration, treatment, and/or biopsy of a target site.  
       [0005] Unfortunately, some critically ill patients requiring high levels of airway pressure are unable to tolerate single lung ventilation. Consequently, these critically ill patients may not be candidates for a VATS procedure, and the traditional thoracotomy with its attendant pain, morbidity, and long recovery duration is still required. Another contraindication to a VATS procedure is the inability of the patient to tolerate a general anesthetic with single-lung ventilation. This situation can occur with mechanically ventilated patients in severe respiratory failure. Other patients for which VATS is virtually impossible are those who have undergone pneumonectomy and thus do not have an opposite lung to ventilate.  
       [0006] Unfortunately, intubation, with dual- or single-lung ventilation, and general anesthesia have the potential to cause a great number of side effects and complications. Minor side effects, causing pain and discomfort, include sore throat and damage to teeth (caused by the endotracheal tube), drowsiness, nausea and vomiting, headache, dizziness, and vision problems. Serious complications that can arise through the use of general anesthesia include stroke, heart attack, brain damage, and death.  
       [0007] Thus, what is needed is a device and method for creating a working space in the thoracic cavity for performing a (VATS) procedure in the presence of an inflated lung, without the necessity of utilizing intubation techniques and general anesthesia.  
       SUMMARY OF THE INVENTION  
       [0008] Accordingly, it is an advantage of the present invention that a soft tissue retraction device for an endoscopic instrument is provided that noninjuriously urges tissues within a body cavity away from a target site.  
       [0009] It is another advantage of the present invention that a soft tissue retraction device is provided that can readily mount to a variety of existing and upcoming endoscopic instruments.  
       [0010] Yet another advantage of the present invention is that a method is provided for performing a video-assisted thoracic surgery in the presence of inflated lung tissue using an endoscopic instrument with a soft tissue retraction device.  
       [0011] The above and other advantages of the present invention are carried out in one form by a soft tissue retraction device for an endoscopic instrument used to access a body cavity, the endoscopic instrument including a tubular body having a proximal end and a distal end, the distal end being adapted for placement in the body cavity. The soft tissue retraction device includes an expansion element adapted to mount on the distal end of the tubular body and an activation mechanism in communication with the expansion element for adjusting the expansion element from a collapsed configuration to a deployed configuration. The deployed configuration of the expansion element noninjuriously urges tissues within the body cavity away from a target site to form a working space circumscribed by the expansion element in which to surgically maneuver the endoscopic instrument.  
       [0012] The above and other advantages of the present invention are carried out in another form by a method of performing video-assisted thoracic surgery (VATS) at a target site in a thoracic cavity of a body in the presence of inflated lung tissue. The method calls for creating an incision through an intercostal space of the body into the thoracic cavity. An endoscopic instrument, with a soft tissue retraction device mounted thereon, is inserted through the incision into the thoracic cavity. The endoscopic instrument includes a tubular body having a proximal end and a distal end, the distal end being adapted for placement in the body cavity, and the distal end having an endoscopic tool extending therefrom. The soft tissue retraction device includes an expansion element mounted on the distal end of the tubular body and an activation mechanism in communication with the expansion element for adjusting the expansion element from a collapsed configuration to a deployed configuration. The inserting operation is performed with the expansion element in the collapsed configuration. The method further calls for adjusting the expansion element to the deployed configuration via the activation mechanism to noninjuriously urge the inflated lung tissue within the thoracic cavity away from a target site to form a working space circumscribed by the expansion element. The endoscopic tool is maneuvered within the working space to access the target site. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0013] A more complete understanding of the present invention may be derived by referring to the detailed description and claims when considered in connection with the Figures, wherein like reference numbers refer to similar items throughout the Figures, and:  
     [0014]FIG. 1 shows a perspective view of a soft tissue retraction device in accordance with a preferred embodiment of the present invention;  
     [0015]FIG. 2 shows a perspective view of the soft tissue retraction device of FIG. 1 in a collapsed configuration;  
     [0016]FIG. 3 shows an illustrative perspective view of the soft tissue retraction device of FIG. 1 in use;  
     [0017]FIG. 4 shows a perspective view a soft tissue retraction device mounted on an endoscopic instrument in accordance with an alternative embodiment of the present invention;  
     [0018]FIG. 5 shows a perspective view of the soft tissue retraction device of FIG. 4 in a collapsed configuration;  
     [0019]FIG. 6 shows a cutaway perspective view of the soft tissue retraction device of FIG. 4 in use;  
     [0020]FIG. 7 shows a perspective view of the soft tissue retraction device of FIG. 4 mounted downstream from a moveable joint of a tubular body of an endoscopic instrument;  
     [0021]FIG. 8 shows a cutaway perspective view of another alternative soft tissue retraction device in use;  
     [0022]FIG. 9 shows a perspective view of another alternative soft tissue retraction device;  
     [0023]FIG. 10 shows an illustrative perspective view of the soft tissue retraction device of FIG. 9 in use within the abdominal cavity of a patient;  
     [0024]FIG. 11 shows a perspective view of the soft tissue retraction device of FIG. 4 mounted on a trocar; and  
     [0025]FIG. 12 shows an illustrative perspective view of the soft tissue retraction device of FIG. 4 mounted on a trocar and in use within the abdominal cavity of a patient.  
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0026] Referring to FIGS.  1 - 3 , FIG. 1 shows a perspective view of a soft tissue retraction device  20  in accordance with a preferred embodiment of the present invention. FIG. 2 shows a perspective view of soft tissue retraction device  20  in a collapsed configuration  21 , and FIG. 3 shows an illustrative perspective view of soft tissue retraction device  20  in use. Soft tissue retraction device  20  includes an expansion element  22  and an activation mechanism  24  in communication with expansion element  22 .  
     [0027] Soft tissue retraction device  20  is configured for use with an endoscopic instrument  26 . Endoscopic instrument  26  includes a tubular body  28  having a proximal end  30  and a distal end  32  adapted for placement in a body cavity of a patient  34 . Endoscopic instrument  26  may include a number of endoscopic tools  36 , best shown in FIG. 1, directed through one or more passages (not shown) within tubular body  28  from proximal end  30  and exiting at distal end  32 . Endoscopic tools  36  may include a flexible or rigid endoscopic camera, graspers, forceps, retractors, dissectors, clamps, and so forth, known to those skilled in the art.  
     [0028] Distal end  32  of endoscopic instrument  26 , with soft tissue retraction device  20  mounted thereon, is particularly suited for placement within a thoracic cavity  38 , containing the lungs and heart, of patient  34 . For illustrative purposes, patient  34  is shown in FIG. 3 without a thoracic wall and ribs so as to better visualize the use of soft tissue retraction device within thoracic cavity  38 . Expansion element  22  of soft tissue retraction device  20  advantageously functions to urge inflated lung tissue  40  within thoracic cavity  38  away from a target site  42  to form a working space  44  circumscribed by expansion element  22  in which to surgically maneuver endoscopic tools  36 . Furthermore, expansion element  22  urges inflated lung tissue  40  away from target site  42  without injuring or destroying lung tissue  40 , and without injury or dissection of intervening tissue layers of the chest wall.  
     [0029] Expansion element  22  includes resiliently expandable ribs  46 , a first retaining ring  48  adapted to be slidably disposed about distal end  32  of tubular body  28 , and a second retaining ring  50  adapted to be fixedly disposed about distal end  32  of tubular body  28 . By way of example, second retaining ring  50  is held fixed to distal end  32 , by an endcap  52  that prevents expansion element  22  from slipping off of distal end  32  of tubular body  28 . Alternatively, second retaining ring  50  may be held fixed to distal end  32  by clips, press-fit elements, O-rings, and so forth.  
     [0030] Each of resiliently expandable ribs  46  includes a first end  54  coupled to first retaining ring  48  and a second end  56  coupled to second retaining ring  50 , such that ribs  46  are spaced about a circumference of tubular body  28 . Ribs  46  may be formed from surgical steel, medical grade plastics, and the like. Such materials may be sterilized following surgery for subsequent reuse. Ribs  46  are configured to readily bow outwardly, relative to tubular body, in response to an axially applied force (discussed below). Alternatively, ribs  46  may be formed as an inflatable bladder, and force is applied to ribs  46  in the form of a fluid (i.e., air or an isotonic liquid solution) for inflating ribs  46  so that they bow outwardly. Inflatable bladder structures will be described in greater detail hereinbelow.  
     [0031] In an exemplary embodiment, activation mechanism  24  includes tabs  58  placed proximate proximal end  30  of endoscopic instrument  26 . For example, a collar structure  60  surrounds tubular body  28  of endoscopic instrument  26  and interconnects tabs  58  and first retaining ring  48 . Activation mechanism  24  is used to adjust expansion element  22  from collapsed configuration  21 , shown in FIG. 2, to a deployed configuration  62 , shown in FIGS. 1 and 3. More specifically, a surgeon may push tabs  58  of activation mechanism  24  toward expansion element  22 . When force, as indicated by an arrow  66 , is imparted axially on first retaining ring  48  via collar structure  60 , first retaining ring  48  is propelled closer to second retaining ring  50 . Force  66  subsequently causes ribs  46  to extend outwardly, by a spring-like action, from tubular body  28  to establish working space  44 . Thus, ribs  46  form a cage-like structure that circumscribes working space  44 .  
     [0032] Collar  60  may then be secured in the forward position so that ribs  46  are held in deployed configuration  62  for the duration of the procedure. The cage-like structure of expansion element  22 , makes soft tissue retraction device  20  particularly suited for exploring structures deep within the thoracic cavity, for example, the mediastinum, pericardium, and so forth because ribs  46  can readily urge inflated lung tissue  40  away.  
     [0033] In an alternative configuration, expansion element  22  may be oriented such that the slidable first retaining ring  48  is closer to the tip of distal end  32  of tubular body  28  than the fixed second retaining ring  50 . In such a configuration, activation mechanism  24  would be coupled to first retaining ring  48  such that a pulling action on tabs  58  will propel first retaining ring  48  closer to second retaining ring  50 , to subsequently cause ribs  46  to extend outwardly from tubular body  28  to establish working space  44 .  
     [0034] Soft tissue retraction device  20  may be provided as an after-market device mountable, at the surgeon&#39;s discretion, to a variety of endoscopic instruments. For example, an inner diameter of collar structure  60  and first and second retaining rings  48  and  50 , respectively, may be manufactured slightly larger than the outer diameter of the tubular body of an endoscopic instrument so that device  20  is simply slid onto the tubular body and secured by a retaining element, such as endcap  52 , clip, press-fit element, O-ring, and the like. Alternatively, soft tissue retraction device  20  may be provided affixed to and integral with an endoscopic instrument from an original equipment manufacturer of the endoscopic instrument.  
     [0035] Soft tissue retraction device  20  is advantageously utilized in conjunction with endoscopic instrument  26  during the performance of a video-assisted thoracic surgery (VATS). During such a procedure, patient  34  need not undergo double-lumen endotracheal intubation and single-lung ventilation. Rather, the patient may be sedated and given a local anesthetic at the surgical site. Since intubation, with single-lung ventilation, is not performed, a VATS procedure may be employed for those patients in which a VATS procedure has been previously contraindicated. These patients include critically ill patients unable to tolerate intubation and single-lung ventilation, as well as patients who have previously undergone a pneumonectomy. By performing a VATS procedure on such patients, the pain morbidity, and long recovery duration of the more invasive thoracotomy can advantageously be avoided. In addition, the side effects and serious complications of intubation can advantageously be avoided.  
     [0036] To perform a VATS procedure, once the local anesthetic has taken effect, the surgeon creates an incision, generally less than one inch in diameter, through an intercostal space (i.e., the area between the ribs) of patient  34  into thoracic cavity  38 . A portal, known to those skilled in the art, may optionally be inserted into the incision to prevent the incision from closing. Endoscopic instrument  26 , with soft tissue retraction device  20  in collapsed configuration  21  mounted thereon, is inserted through the portal and into thoracic cavity  38 . After endoscopic instrument  26  is in thoracic cavity  38 , the surgeon can then adjust expansion element  22  to deployed configuration  62  via activation mechanism  24  to urge, or push, inflated lung tissue  40  within thoracic cavity  38  away from target site  42 . Endoscopic tools  36 , extending from distal end  32  of tubular body  28  can then be maneuvered within working space  44  to execute the desired diagnostic or surgical procedure, or to deliver medication to target site  42 . Following the procedure, tissue retraction device  20  is adjusted back to collapsed configuration  21  and endoscopic tool  26  is removed from patient  34 .  
     [0037] Referring to FIGS.  4 - 6 , FIG. 4 shows a perspective view a soft tissue retraction device  68  mounted on an endoscopic instrument  70  in accordance with an alternative embodiment of the present invention. FIG. 5 shows a perspective view of soft tissue retraction device  68  in a collapsed configuration  72 . FIG. 6 shows a cutaway perspective view of soft tissue retraction device  68  in use.  
     [0038] Like endoscopic instrument  26  (FIG. 1), endoscopic instrument  70  includes a tubular body  74  having a proximal end  76  and a distal end  78  adapted for placement in thoracic cavity  38  of patient  34 . Endoscopic instrument  70  may include endoscopic tools  36  directed through passages within tubular body  74  from proximal end  76  and exiting at distal end  78 .  
     [0039] An expansion element  80  of soft tissue retraction device  68  includes an inflatable bladder  82  configured for mounting on distal end  78  of tubular body  74  of endoscopic instrument  70 . Inflatable bladder  82  includes a contoured wall section  83  tapering to a closed vertex  84  and having an open base  86  opposite closed vertex  84 . Closed vertex  84  is “closed” by virtue of its attachment to tubular body  74  of endoscopic instrument  70 . For example, an O-ring structure  88  is formed at closed vertex  84 . O-ring structure  88  is stretched over and held onto tubular body  74  by elastic force. In such a configuration, soft tissue retraction device  68  may be a disposable unit that is optionally placed onto distal end  78  of tubular body  74  prior to insertion into thoracic cavity  38 .  
     [0040] Expansion element  80  further includes a fluid passageway  90  having a first end  92  in fluid communication with inflatable bladder  82  and having a second end  94 . Fluid passageway  90  is directed toward proximal end  76  of tubular body  74  such that second end  94  is near proximal end  76 . An inflation port  96  is coupled to second end  94  of fluid passageway  90 . An activation mechanism  98 , in the form of a fluid filled syringe, couples to inflation port  96 . In a preferred embodiment, fluid within syringe  98  is an isotonic liquid solution, such as saline solution. The saline solution is ejected from syringe  98  and introduced into inflatable bladder  82  via fluid passageway  90 . The saline solution subsequently inflates bladder  82  to adjust bladder  82  to a deployed configuration  100 , as best shown in FIGS. 4 and 6.  
     [0041] During a VATS procedure, an incision is made through the chest wall  102  of patient  34  at the intercostal region. Endoscopic tool  70  with soft tissue retraction device  68  mounted thereon is inserted through the incision and deployed in thoracic cavity  38 . Inflatable bladder  82 , in deployed configuration  100 , establishes a cone-shaped working space  104  in which open base  86  faces toward distal end  78  of tubular body  74  of endoscopic instrument  70 . The establishment of cone-shaped working space  104 , with open base  86  facing toward distal end  78 , makes inflatable bladder  82  particularly suited for exploring the surface of inflated lung tissue  40 . Endoscopic tools  36 , such as an endoscopic camera and graspers, may extend from distal end  78  of a tubular body  74  within working space  104  to access a target site  106  on inflated lung tissue  40  for visualization, biopsy, and/or treatment.  
     [0042] In an alternative embodiment, inflatable bladder  82  may additionally include ribs (not shown) built into contoured wall section  83  that provide additional strength to expansion element  80  for noninjuriously urging inflated lung tissue  40  away from target site  106 . Alternatively, ribs (not shown) may have first ends coupled to a perimeter  108  of open base  86  and have second ends coupled about tubular body  74  of endoscopic instrument. Thus, the ribs would radiate outwardly from tubular body  74 , when soft tissue retraction device  68  is adjusted to deployed configuration  100 , to further provide noninjurious retention of inflated lung tissue  40 .  
     [0043]FIG. 7 shows a perspective view of soft tissue retraction device  68  mounted downstream from a moveable joint  110  of a tubular body  112  of another endoscopic instrument  114 . Moveable joint  110  is proximate a distal end  116  of tubular body  112 . Expansion element  80  of soft tissue retraction device  68  is adapted to be mounted downstream from moveable joint  110 . As such, when moveable joint  110  is actuated by a surgeon, distal end  116  of tubular body  112 , with expansion element  80  mounted thereon, can be directed toward a target site. Although, soft tissue retraction device  68  is shown mounted downstream from moveable joint  110 , other soft tissue retraction devices described herein, such as soft tissue retraction device  20  (FIG. 1), may alternatively be mounted downstream from moveable joint  110 .  
     [0044]FIG. 8 shows a cutaway perspective view of another alternative soft tissue retraction device  118  in use. Soft tissue retraction device  118  includes an expansion element  120  having a contoured wall section  122  tapering to a closed vertex  124  and having an open base  126  opposite closed vertex  124 . Expansion element  120  may be a resiliently expandable structure in communication with an activation mechanism, such as activation mechanism  24 , as discussed in connection with FIGS.  1 - 3 . Alternatively, expansion element  120  may be an inflatable bladder and the activation mechanism may be syringe  98 , as discussed in connection with FIGS.  4 - 6 .  
     [0045] Expansion element  120  further includes expandable ribs  128  having first ends  130  coupled to a perimeter  132  of open base  126  and having second ends  134  configured for attachment about a distal end  136  of a tubular body  138  of an endoscopic instrument. By way of example, second ends  134  of ribs  128  may be coupled to an O-ring structure  140 . O-ring structure  140  may be stretched over and held onto tubular body  138  by elastic force. In such a configuration, soft tissue retraction device  118  may be optionally placed onto distal end  136  of tubular body  138  prior to insertion into thoracic cavity  38 . Alternatively, ribs  128  may be coupled to a slidable ring structure (not shown), with closed vertex  124  attached to a tip of distal end  136 . The slidable ring structure is actuated in a manner similar to that discussed in connection with activation mechanism  24  (FIG. 1).  
     [0046] Following insertion into thoracic cavity  38 , expansion element  120  is adjusted to a deployed configuration  144 , either through a mechanical mechanism or inflation, and ribs  128  radiate outwardly from tubular body  138 . In deployed configuration  144 , a dome-shaped working space  146  is formed in which open base  126  faces proximal end  142  of tubular body  138 , while closed vertex  124  of expansion element  120  noninjuriously urges inflated lung tissue  40  away from a target site  148 . The establishment of dome-shaped working space  146 , with open base  126  facing toward proximal end  142 , makes expansion element  120  particularly suited for exploring, for example, the pleural membrane using endoscopic tools  36 .  
     [0047]FIG. 9 shows a perspective view of another alternative soft tissue retraction device  150 . Soft tissue retraction device  150  includes an expansion element  152  adapted to be mounted to a distal end  154  of a tubular body  155  of an endoscopic instrument (not shown). Expansion element  152  includes first and second opposing bases  156  and  158 , respectively, mounted about tubular body  155 . Expansion element  152  further includes a lateral surface  160  interposed between adjoining boundaries  162  of each of first and second bases  156  and  158 . Lateral surface  160  is contoured so that expansion element  152  has a generally cylindrical form. Lateral surface  160  includes an opening  164  formed therein for accessing a target site (not shown) within thoracic cavity  38  (FIG. 1). For example, endoscopic tool  36 , in the form of an endoscopic camera, can view a target site from opening  164 .  
     [0048] Like the structures discussed above, soft tissue retraction device  150  is configured to noninjuriously urge inflated lung tissue  40  (FIG. 3) away from a target site (not shown). Furthermore, soft tissue retraction device can be a resiliently expandable material or an inflatable bladder, and can be permanently affixed to the endoscopic instrument, or can be selectively mounted to the endoscopic instrument.  
     [0049]FIG. 10 shows an illustrative perspective view of soft tissue retraction device  150  in use within the abdominal cavity  166  of a patient  168 . Although the aforementioned soft tissue retraction devices were described for use within the thoracic cavity of a patient, any of the soft tissue retraction devices, including soft tissue retraction device  150 , may alternatively be utilized within abdominal cavity  166  of patient  168 . In such a capacity, a surgeon can perform a laparoscopic procedure in which an endoscopic instrument is inserted into abdominal cavity  166  for exploring, diagnosing, and treating disease processes of the internal organs within abdominal cavity  166 .  
     [0050] Expansion element  152  of soft tissue retraction device  150  is configured to noninjuriously urge the internal organs of abdominal cavity  166  away from a target site  170 . Since expansion element  152  urges the internal organs of abdominal cavity  166  away from target site  170 , a surgeon need not distend abdominal cavity  166  with carbon dioxide, as is typically done during a laparoscopic procedure, in order to access the internal organs.  
     [0051] Referring to FIGS.  11 - 12 , FIG. 11 shows a perspective view of soft tissue retraction device  68  mounted on a trocar  172  of an endoscopic instrument  174 . FIG. 12 shows an illustrative perspective view of a number of soft tissue retraction devices  68 , each being mounted on a separate trocar  172  and in use within the abdominal cavity  176  of a patient  178 . Although trocar  172  is described in terms of its use within the abdominal cavity, it should be understood that trocar  172  of endoscopic instrument  174  may alternatively be employed for accessing the thoracic cavity.  
     [0052] Trocar  172  includes a tubular body  180  having a proximal end  182  and a distal end  184  adapted for placement in abdominal cavity  176  of patient  178 . Endoscopic instrument  174  may include a number of endoscopic tools  36 , directed through one or more passages (not shown) within tubular body  180  from proximal end  182  and exiting at distal end  184 .  
     [0053] As discussed previously, expansion element  80  of soft tissue retraction device  68  includes inflatable bladder  82  having contoured wall section  83  tapering to closed vertex  84  and having open base  86  opposite closed vertex  84 . Inflatable bladder  82  is configured for mounting on distal end  184  of trocar  172 . Thus, closed vertex  84  is “closed” by virtue of its attachment to tubular body  180  of trocar  172 . In addition, open base  86  is configured to face toward distal end  184  of trocar  172 .  
     [0054] As shown, expansion element  80  further includes fluid passageway  90  having first end  92  in fluid communication with inflatable bladder  82  and having a second end  94 . Fluid passageway  90  is directed toward proximal end  182  of tubular body  180  such that second end  94  is near proximal end  182 . Activation mechanism  98 , in the form of a fluid filled syringe, couples to inflation port  96  at second end  94  of fluid passageway  90  for adjusting bladder  82  to deployed configuration  100 .  
     [0055] During a laparoscopic procedure, a surgeon creates one or more incisions through an abdominal wall  186  of patient  178  into abdominal cavity  176 . Trocar  172  of endoscopic instrument  174  is inserted, with expansion element  80  in a collapsed configuration, through each of the incisions into abdominal cavity  176 . Once distal end  184  of trocar  172  is in abdominal cavity  176 , the surgeon adjusts expansion element  80  from the collapsed configuration to deployed configuration  100 . Endoscopic tools  36  are then directed through trocar  172  to extend from distal end  184 .  
     [0056] With conventional endoscopic instruments, bodily fluid, such as blood, often seeps from the incisions created in the abdominal wall of a patient and visually obstructs the lens of the endoscopic camera device. Such an occurrence undesirably slows down the progress of the laparoscopy because a surgeon is obligated to remove the endoscopic camera from the abdominal cavity to wipe off the lens, apply an anti-fog substance to the lens, and so forth, in order to more clearly view the patient&#39;s internal organs on a television monitor.  
     [0057] However, in accordance with the present invention, when expansion element  80  is adjusted to deployed configuration  100 , blood  188  is advantageously directed along an outer surface  190  of contoured wall section  83  of expansion element  80  and away from a working space  192  circumscribed by expansion element. Endoscopic tools  36 , in particular an endoscopic camera, is then maneuvered within working space  192  so that a surgeon may clearly visualize a target site within abdominal cavity  176 .  
     [0058] In summary, the present invention teaches of a soft tissue retraction device for an endoscopic instrument. The soft tissue retraction device, in a number of configurations, includes an expansion element that is adapted to mount on the distal end of a tubular body of the endoscopic instrument. The expansion element pushes against tissue, without injuring the tissue, to form a working space within which endoscopic tools can be surgically maneuvered. The soft tissue retraction device is particularly suited to noninjuriously urge inflated lung tissue away from a target site during a video-assisted thoracic surgery (VATS), thereby eliminating the need for the double-lumen intubation and single-lung ventilation techniques currently in use. In addition, the soft tissue retraction device may be utilized in the abdominal cavity to urge the soft internal organs away from a target site during a laparoscopic procedure. The soft tissue retraction device also serves to direct bodily fluid, such as blood, away from a working space so that a target site may be more clearly visualized. The soft tissue retraction device may be installed as original, sterilizable, equipment on a new endoscopic instrument. Alternatively, it may be provided as an after-market device that readily mounts to a variety of existing and upcoming endoscopic instruments and trocar devices.  
     [0059] Although the preferred embodiments of the invention have been illustrated and described in detail, it will be readily apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.