Abstract:
An abrading device for use in irritating and blotting a surgical area, preferably the area between the chest wall and lung of a patient, to allow the user to more easily insert and remove the surgical device reducing contact with surrounding tissue and wound edges. The device is primarily comprised of a cannula, a plurality of radial springs, an abrasive tip, an actuator and an adjuster. The actuator is configured to selectively move the abrasive tip and plurality of radial springs into and out of the cannula. The adjuster allows the user to selectively expand or collapse the abrasive tip.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     MICROFICHE APPENDIX 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to the field of surgical devices. More specifically, this invention comprises an abrading device that is used for creating abrasions on a membrane, such as the pleural membrane. 
     2. Description of the Related Art 
     Pleurodesis is a medical procedure in which the pleural space, the space between the chest wall and the lung of a patient, is obliterated. This is commonly done in order to prevent the recurrence of pneumothorax or pleural effusion. Pleurodesis is accomplished by irritating the parietal pleura, thereby creating abrasions on the chest wall, which causes adhesion between the wall and the lung of a patient. Sealing off of the pleural space prevents unwanted fluid or air from entering and occupying the area after the surgery. 
     Pleurodesis is typically performed during a thoracotomy or a thoracoscopy. Both surgical techniques are used to enter the chest to perform any number of different medical procedures. The difference between the two techniques is related to the size of the incision that is made in the patient. The incision for a thoracotomy is made on the side of the patient&#39;s chest and is typically four to six inches long. In a thoracoscopic operation several small incisions, generally ¼ to 1 inch in diameter, are made in different places around the chest. 
       FIG. 2  shows a prior art thoracoport  32  with a thorascoscope  30  inserted through the thoracoport  32 . Thoracoports  32 , small tubes or pipe structures, are typically placed into the small incisions through the chest wall to allow for easy insertion of other small instruments, thereby reducing the risk of damage to surrounding tissues during insertion and withdrawal. A thoracoscope  30 , or small fiber optical camera, is inserted through at least one of the thoracoports  32  to view the inside of the chest. This minimally invasive operation allows surgeons to have maximum mobility inside the chest without putting pressure on the ribs. It also allows a surgeon to enter and exit the chest with little trauma to the nerves that travel along the bottom edge of each rib. The benefits to patients include reduced post-operative pain, a faster recovery and less scarring. 
     Upon nearing the end of a thoracotomy or a thoracoscopy, a surgeon would typically perform surgical pleurodesis by irritating the pleural membrane with a rough pad.  FIG. 1  illustrates the existing equipment used for this process. Surgeons attach prior art gauze  36  to a prior art Kelly clamp  34  and physically rub the rough pad along the pleural membrane. Kelly clamp  34  is a medical tool that resembles a pair of scissors; however, the blade is replaced by a locking clamp. A surgeon using a Kelly clamp  34  during a thoracotomy would typically have to disturb the incision site and surrounding tissue in order to push the abrasive gauze  36  into the patient&#39;s body between the chest wall and lung. This causes an increase in trauma to the surrounding tissue and likely extension of the initial incision site. Additionally, it is difficult to view the tissue that is being irritated, as the insertion of the Kelly clamp  34  blocks the surgeon&#39;s view. 
     Performing surgical pleurodesis at the end of a thoracoscopy is more difficult than in the thoracotomy. Because the incisions are small, a surgeon must stretch the incision site to fit the Kelly clamp  34  down into the pleural membrane. Again, the result is increased trauma, likely incision extension and difficulty in viewing the irritation process. Since the incision site is so small the reader will note that the insertion of the Kelly clamp  34  and rough gauze  36  is difficult and likely causes more trauma to the body than would be caused when working with a larger incision site. 
     Abrading devices have not previously been small enough to fit through a thoracoport or other small opening. Additionally, the abrading surface, usually a rough pad, has not previously been retractable into a smooth tube. A retractable abrading surface is particularly advantageous because a smooth and thin instrument can enter the patient&#39;s body through a thoracoport  32  or other small incision with little to no contact with “wound edges” and can be completely removed from the patient&#39;s chest without rubbing against the surrounding tissue. Furthermore, if the device is able to fit through a thoracoport  32 , a thoracoscope  30  can be utilized to view the complete abrading process giving the surgeon extensive visibility to properly irritate the chest wall for complete adhesion. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention comprises an abrading device for irritating and blotting a membrane, particularly the pleural membrane. The device is small enough to be inserted and withdrawn through a prior art thoracoport. It includes a proximal end configured to be gripped by a surgeon and a distal end configured to be inserted through a thoracoport into the patient. The distal end includes a collapsible abrasive “spider” housed within a cannula. The spider can be collapsed and withdrawn into the cannula. In this state, the surgeon can insert the distal end through a thoracoport into the pleural space. The surgeon then manipulates adjustment features located on the invention&#39;s proximal end to deploy and expand the spider. 
     Once the spider is deployed and expanded, the surgeon grips the proximal end and manipulates the device so that the spider abrades the walls of the pleural space. The invention&#39;s cannula is small enough so that a thorascoscope can remain in the thoracoport with the cannula and be used to observe the abrading process. Once the abrading process is complete, the surgeon can collapse the spider and withdraw it back into the distal end of the cannula. The device can then be withdrawn back through the thoracoport. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a perspective view, showing a prior art Kelly clamp. 
         FIG. 2  is a perspective view, showing a prior art thoracoport with a prior art thorascoscope inserted therein. 
         FIG. 3  is a perspective view, showing the abrasive “spider” of the present invention in a fully expanded position. 
         FIG. 4  is a perspective view, showing the actuator. 
         FIG. 5  is a perspective view, showing the spider assembly and how it relates to the inner tube. 
         FIG. 6  is an exploded perspective view, showing the components located on the invention&#39;s proximal end. 
         FIG. 7  is an exploded perspective view, showing the components located on the invention&#39;s proximal end. 
         FIG. 8  is a perspective view, showing the components located on the invention&#39;s proximal end. 
         FIG. 9  is a perspective view, showing the components located on the invention&#39;s proximal end. 
         FIG. 10  is a section view, showing the components located on the invention&#39;s proximal end. 
         FIG. 11  is a section view, showing the entire invention with the spider collapsed and retracted in the cannula. 
         FIG. 12  is a section view, showing the spider extended and partially expanded. 
         FIG. 13  is a perspective view, showing the entire invention with the spider collapsed and retracted. 
         FIG. 14  is an elevation view, showing the spider extended but not expanded. 
         FIG. 15  is a perspective view, showing the spider extended and expanded. 
         FIG. 16  is a perspective view, showing the spider extended and expanded. 
       
         
           
                 
               
                 
                 
                 
                 
               
             
                 
                     
                 
                 
                   REFERENCE NUMERALS IN THE DRAWINGS 
                 
                 
                     
                 
               
               
                 
                     
                 
               
            
             
                 
                   10 
                   expansion knob 
                   12 
                   handle 
                 
                 
                   14 
                   cannula 
                   16 
                   locking collar 
                 
                 
                   18 
                   abrasive tip 
                   20 
                   adjuster 
                 
                 
                   22 
                   spider 
                   24 
                   mechanical assist rod 
                 
                 
                   26 
                   actuator 
                   28 
                   thread engaging key 
                 
                 
                   30 
                   thorascoscope 
                   32 
                   thoracoport 
                 
                 
                   34 
                   Kelly clamp 
                   36 
                   gauze 
                 
                 
                   38 
                   lever 
                   40 
                   lever slot 
                 
                 
                   42 
                   inner tube 
                   44 
                   washer 
                 
                 
                   46 
                   fastener 
                   48 
                   handle assembly 
                 
                 
                   50 
                   adjuster slot 
                   52 
                   thrust flange 
                 
                 
                   54 
                   helical thread 
                   56 
                   lever receiver 
                 
                 
                   58 
                   radial spring 
                   60 
                   hub 
                 
                 
                   64 
                   hollow receiver 
                   66 
                   end wall 
                 
                 
                     
                 
               
            
           
         
       
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is a device for inserting and deploying an expanding abrasive element.  FIG. 3  shows the core of this abrasive element, labeled as spider  22 . Spider  22  is formed by attaching an array of radial springs  58  to a hub  60  on one end and a locking collar  16  on the opposite end. The springs are made of a thin and resilient material which can undergo substantial deformation without experiencing plastic deformation (an example of a suitable material would be a thin spring steel). By varying the distance between the hub and the locking collar, the radial springs can be selectively bowed outward or collapsed inward. In use, the array of radial springs will be covered by an abrasive (and absorptive) tip which will actually make contact with the surface to be abraded. 
     The components of the invention will now be described in detail, after which the assembly of the components and their subsequent use will be described.  FIG. 4  shows actuator  26 , which is a generally cylindrical component having a hollow center  64  passing through it from one end to the other. Helical thread  54  is provided over at least a portion of its outer surface. Thrust flange  52  is located on its distal end. A preferably separate lever  38  is configured to lock into lever receiver  56  in the side of actuator  26 . 
       FIG. 5  shows the assembly which is used to expand and contract spider  22 . As discussed previously, the radial springs of spider  22  are each connected at their distal ends to hub  60  and at their proximal ends to locking collar  16 . Locking collar  16  is attached to inner tube  42 , which is a long hollow tube. Locking collar  16  may in fact simply be an integral part of inner tube  42 . Mechanical assist rod  24  passes through inner tube  42  and connects to hub  60 . The detail view shows how fastener  46  is used to connect the mechanical assist rod to the spider. Many types of fasteners could be used. 
     Those skilled in the art will readily appreciate the operational implications of the assembly shown in  FIG. 5 . If the mechanical assist rod is pulled through the inner tube to the right in the orientation shown in the view, hub  60  will be forced toward locking collar  16 . This motion will cause spider  22  to progressively expand into the balloon shape shown. 
       FIG. 6  is an exploded view showing the features used to deploy and expand the spider, all of which are located on the invention&#39;s proximal end. Handle  12  provides a gripping surface for a surgeon to hold and manipulate the invention. It is essentially a hollow tube, with a lever slot  40  opening through its side wall. Inner tube  42  passes through its hollow interior toward the distal end of the device. Actuator  26  is joined to inner tube  42 . The actuator and inner tube may in fact be formed as a single integral piece. 
     Mechanical assist rod  24  passes out the open proximal end of actuator  26 . Adjuster  20 , which is still another hollow cylindrical component, is configured to slip over the exterior of the threaded portion of actuator  26 . The adjustor&#39;s side wall opens into adjuster slot  50 , which is configured to receive thread engaging key  28 . The thread engaging key includes an inward-facing extension configured to engage helical thread  54  in actuator  26 . The proximal end of adjuster  20  includes expansion knob  10 , which preferably has gripping features. 
       FIG. 7  shows the same assembly after adjuster  20  has been slipped over actuator  26  and thread engaging key  28  has been pressed into place.  FIG. 8  shows the same assembly after adjuster  20  and actuator  26  have been pushed down into the hollow interior of handle  12  (Handle  12  is shown as hidden lines). At this point, lever  38  may be inserted through lever slot  40  and into lever receiver  56  in actuator  26 . Those skilled in the art will realize that this action effectively locks the handle, the actuator, and the adjuster together. 
     The interaction between lever  38  and lever slot  40  allows the adjuster assembly to move between two states with respect to the handle.  FIG. 8  shows the first of these two states. The reader will observe how the lever slot includes two notches—one at the proximal end of the handle and one closer to the distal end of the handle. The lever can be rotated into one of these notches to lock the adjuster assembly in one of two positions. In  FIG. 8 , lever  38  has been placed in the proximal notch. This leaves the adjuster and expansion knob protruding significantly from the proximal end of the handle. 
     In  FIG. 9 , the user has grasped lever  38  and manipulated it so that it has moved into the long portion of lever slot  40  and then toward the distal end of the lever slot. After reaching the lever slot&#39;s distal end, lever  38  has been placed in the distal notch. This action locks the adjuster assembly in a second state, in which the adjuster and the expansion knob have moved toward the distal end of the handle. The reader will thereby appreciate how the interaction of the lever and the lever slot allows the device to be “indexed” between two different states. Those skilled in the art will realize that many other devices could be employed to create this indexing feature, with a spring plunger engaging a pair of detents being a good alternative example. 
       FIGS. 11 and 12  serve to illustrate the significance of the two indexed positions.  FIG. 11  is a section view through the entire invention, in which the adjuster assembly is indexed to the position where adjuster  20  and expansion knob  10  protrude well clear of the proximal end of handle  12 . Lever  38  rests within the proximal notch of the lever slot. 
     Cannula  14  extends away from the distal end of handle  12  toward the distal end of the device. It contains inner tube  42  and mechanical assist rod  24 . In the indexed position shown, spider  22  is also contained within the cannula in a collapsed state. If the user manipulates the lever to place the lever within the distal notch of the lever slot, spider  22  will be pushed clear of the cannula.  FIG. 12  shows the invention after the lever has been manipulated to lie in the distal notch of the lever slot. The reader will observe how the spider has been pushed clear of the cannula. The surgeon may then manipulate expansion knob  10  to expand the spider (it is shown partially expanded in the view). 
     Turning now to  FIG. 10 , the spider&#39;s deployment will be explained in more detail.  FIG. 10  is a section view showing the handle, the adjuster, and associated components. Lever  38  is shown positioned in the distal notch of the lever slot. In this position, actuator  26  has moved toward the distal end of the device. Thrust flange  52  bears against end wall  66  of handle  12 , thereby preventing further distal motion of the actuator with respect to the handle. It is thereby “anchored” against the handle. 
     If the user then rotates adjuster  20  by gripping expansion knob  10 , thread engaging key  28  will engage helical thread  54  in actuator  26  and cause adjuster  20  to move proximally and distally with respect to the actuator and the handle (depending on whether the thread is a right-hand or left-hand thread and depending upon the direction of rotation of the expansion knob). Mechanical assist rod  24  is linked to the expansion knob, preferably by a rotating joint such as washer  44 . Moving the adjuster in and out of the device thereby causes mechanical assist rod  24  to move in and out of the device. The distal end of the mechanical assist rod is attached to the spider. The motion thus described will therefore expand and contract the spider. 
     In one alternative embodiment the adjuster could contain hash-marks on its body which measure the relative expansion of the abrasive tip. As the adjuster moves in and out of the handle, the user would observe the hash-marks in relation to the handle describing the degree to which the balloon had expanded. A window on the handle could be installed to view the hash-marks through, as the adjuster turns, in order to more easily read the measurement. 
       FIG. 13  shows a perspective view of the device with the spider retracted into the cannula. In this state the surgeon can insert the cannula through a thoracoport in the patient&#39;s chest. The surgeon would then use the lever to “index” the device to the deployed state in which the collapsed spider extends beyond the end of the cannula. The deployed state is shown in  FIG. 14 . The reader will observe that the lever is locked into the distal notch of the lever slot. 
     The spider is fully deployed, but is still in a collapsed state. The surgeon then rotates expansion knob  10  in the appropriate direction to expand and contract the spider as desired.  FIG. 15  shows spider  22  in a fully expanded state suitable for use. Of course—as mentioned previously—the radial springs of the spider are preferably covered with an abrasive material in use.  FIG. 16  shows how abrasive tip  18  covers the radial springs and provides a smoother external contour. The abrasive tip is preferably an elastic material which will fit tightly over the spider&#39;s frame in both a collapsed and expanded state. It is preferably coated with an appropriate surface texture to facilitate the abrading operation. The material is preferably absorptive as well as abrasive. 
     Once the surgeon completes the abrading operation, the expansion knob is rotated in the appropriate direction to collapse the spider. The lever is then indexed toward the proximal position in order to withdraw the spider into the distal end of the cannula. The entire device may then be pulled back out through the thoracoport (or conventional incision if no thoracoport is used). 
     Many suitable materials can be used to make the components of the device. One should bear in mind, however, the need for complete disposal of the device. Thus, all of the components are preferably made of disposable materials which can be thrown away after every use. Alternatively, many components of the device could be made of stainless steel so as to allow for repeated sterilization of the device. In this embodiment, other components—such as the abrasive tip—are preferably made of disposable materials which will be replaced after every use. 
     The preceding description contains significant detail regarding the novel aspects of the present invention. It should not be construed, however, as limiting the scope of the invention but rather as providing illustrations of the preferred embodiments of the invention. As an example, the expansion and deflation of spider  22  could be accomplished by pushing and pulling expansion knob  10  and adjuster  20  utilizing a spring activated adjusting nut as opposed to a fixed adjusting nut. As an additional example, a cable could be substituted for the mechanical assist rod (provided that the radial springs were strong enough to maintain tension on the cable). Different mechanisms could also be used for the deflation or expansion of spider  22 . Thus, the scope of the invention should be fixed by the following claims, rather than by the examples given.