Device for the fracture of the blood vessel lining
BACKGROUND OF THE INVENTION 
     In the art of vascular surgery it is often desired to remove the inner layer which is fatty in nature from a vessel without cutting the vessel entirely through at a certain point but nevertheless cutting the inner layer to such a degree that at a point some distance away the blood vessel can be opened and the inner sleeve so to speak can be pulled out of the vessel. 
     In an effort to solve this problem applicant began experiments in the design of an instrument which would meet this need since no device was presently available to enable vascular surgeons like himself to perform this frequently needed procedure. The first step that the method requires is a holding in place of the blood vessel at the spot selected for the internal fracture of the inner layer of the blood vessel. This was achieved by the creation of a guillotine-like arrangement with an upper anvil member which contained a dull blade resting on one side of the blood vessel and a hammer-like opposing jaw which held the blood vessel therebetween. The next problem was to apply only that pressure to the pincers of the guillotine that would be sufficient to cut the softer inner layer of the blood vessel but leave intact the tougher outer muscular layer of the blood vessel. This was achieved by positioning two springs around a central rod or core which connected to the hammer member of the guillotine on one end and a pressure retaining handle on the other. When these springs were first impressed by sliding them toward the guillotine hammer and then suddenly released to snap back an impact sharply against a protuberance of the rod, the shock wave generated was transmitted down the rod and into the hammer with only sufficient momentum to cause a controlled cutting or severance of the vessel. Therefore as a result of this process of thought and design there was created a new instrument which shall be described in greater detail by the following written description and reference to the several drawings and pictorial representations of the device. The several objects of the invention will become clear from a reading of the specification and need not be more specifically elaborated at this point although it should be pointed out that a surgical method as well as a new surgical instrument comprises the subject matter of this invention. 
    
    
     BRIEF DESCRIPTION OF THE INVENTION 
     Accordingly there is described herein a new device for the partial fracture of various layered vessels such as blood vessels. This device will be described more particularly by reference to the several FIGS. 1 through 4 of the attached drawing. 
     FIG. 1 is a prospective view of the instrument with the jaws of the guillotine open and a blood vessel resting on the bottom jaw which we refer to as the hammer of the guillotine. 
     FIG. 2 shows the hammer and the anvil members of the guillotine closed about a blood vessel which is squeezed therein. 
     FIG. 3 shows also in perspective the movement of the two hands of the user with one hand releasing the downward pressure which kept the jaws of the guillotine from closing. The other hand meanwhile is compressing the spring member which is located about a central rod or core which connects to the hammer of the guillotine. 
     Finally, FIG. 4 shows the perspective view of the last step of the cutting operation wherein the compression spring members are suddenly released so that they snap back and create an impact which travels along the central core and is transmitted to the hammer portion of the guillotine. 
    
    
     The invention will now be explained in greater detail by specific reference to FIGS. 1 through 4 of the drawing. 
     Turning first to FIG. 1 of the drawing there is shown a device which comprises an anvil 1 and a hammer 2 which is slideably attached to a slider arm 3 which passes through a slot in the anvil 1 so that the two members are constantly aligned. The slider has a protuberance or a stop member 4 which limits the degree to which the jaws of the guillotine can be opened. The anvil member is controlled by a guide arm 5 which passes through an alignment piece 10 which has one end thereof attached to a central rod 6 for holding the hammer while the other end of the alignment piece 10 is fixably attached to the guide 5. Surrounding the central rod for the hammer member there are a series of springs. The first or proximal spring 7 is forced against a retainer 11 which is interposed between the proximal spring 7 and the alignment piece 10. The central rod is free to slide upward or downward in response to finger pressure exerted to the rod by a finger pressure button 12. While the device operates so that the finger gripper knob 13 is held firmly between the forefinger and the second finger the guide for the impact blade anvil 5 is also clutched between the ends of the forefinger and the second finger and the spring is first compressed by a movement of the other hand of the user and then released to impact against the shock knob of the central rod 9. 
     The impact of the distal spring 8 against the shock knob 9 of the central rod causes a wave of shock to travel down the central rod 6 and to be conveyed to the hammer 2 and transmitted from the hammer into the blood vessel 15 which presses against the blade 14 of the anvil 1. This causes the internal cutting or cleavage of the blood vessel. 
     It is essential to recognize in the present invention that the impact of the blade 14 which is a dull blade and physically attached to the anvil 1 is controlled by the level of shock or impact which is conveyed thereto by the collision of the spring released against the shock knob 9. It is clear that this shock or impact is sufficient to cleave the inner layer of the blood vessel but insufficient to cleave the outer layers of musculature which surround the same. 
     While the embodiments described in the drawing are intended to illustrate the invention it is within the scope of the invention to encompass all the variations related thereto and consequently all variations on this concept are considered to be within the scope of the appended claims.