Abstract:
An ultrasonic instrument includes generator of ultrasonic energy; a connecting body that receives ultrasonic energy from the generator and having an end from which the energy exits and a coupler at such end exterior of the connecting body having an inlet aspiration flow passage for receiving aspiration flow force from a source. A work tip has its proximal end connected to the coupler to receive the generated ultrasonic energy and a distal end from which the ultrasonic energy is supplied to the operating site to emulsify material. The work tip has an aspiration passage that is in communication with an aspiration passage in the coupler that communicates with the inlet passage and at least one of the work tip is detachable from the coupler and coupler detachable from the connecting body. Aspiration fluid flow force is provided through the coupler to the work tip aspiration passage without coming into contact with the interior of the connecting body to thereby permit removal of the work tip so that the instrument can be reused by replacing the work tip and without sterilization of the connecting body.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The use of ultrasonic instruments in surgical applications is well known. One widely used type of instrument is an ultrasonic handpiece that is used in opthalmological applications, such as in the removal of cataracts from the eye. A typical instrument uses a magnetostrictive transducer formed by a stack of laminations surrounded by a coil of wire to which alternating current energy is applied. The stack of laminations converts the electrical energy to mechanical vibratory energy. A work tip is at the distal end of the handpiece that is connected to the transducer by a connecting body. The mechanical vibratory energy produced by the transducer is conveyed to the distal end of the work tip and this energy is applied close to or against a piece of tissue that is emulsified by the vibratory energy.  
           [0002]    Such a handpiece usually utilizes a source of aspiration flow force so that the emulsified tissue can be removed from the operating site. The aspiration force can be provided by, for example, a peristaltic type suction pump and there is a fluid connection between the pump and the work tip, usually through a central aspiration passage formed in the work tip that is in communication with the aspiration force pump through a conduit that is connected to a fitting on the handpiece that is in communication with the tip central passage. The aspiration flow force passage also can extend through the connecting body. Hand pieces of this type can also have a sleeve, or cocoon, that surrounds and is spaced from the work tip to form a passage through which an irrigation fluid is supplied from an external source. The irrigation fluid exits from this passage at or near the distal end of the tip to supply the irrigation fluid to the operating site.  
           [0003]    After each use, the complete handpiece can be sterilized, such as by a conventional gas sterilization technique, or the work tip alone can be immersed in a liquid sterilizing solution. In instruments of this type there often is a threaded connection between the proximal end of the work tip and the connecting body. The threaded connection is relatively permanent in the sense that it is broken only when the work tip has to be replaced, this occurring after many uses of the handpiece.  
           [0004]    A need exists to provide an ultrasonic handpiece of the forgoing type in which the work tip would be used for only a single use and then disposed of. This can have a desired advantage of eliminating the need for sterilization of the handpiece, or making sterilization easier, and making conditions for use of the instrument more sanitary from one patient to the next. However, if the work tip is to be made for single use, it becomes necessary to provide an arrangement by which the tip can be easily changed and the aspiration and irrigation flow passages can be easily and reliably established.  
         BRIEF DESCRIPTION OF THE INVENTION  
         [0005]    In accordance with the invention an ultrasonic handpiece is provided in which the work tip is to be replaced after a single use and there can be a quick and reliable provision of the aspiration and irrigation flow forces and fluids to the instrument. While the instrument is described using a magnetostrictive transducer, various features have application to hand pieces that use a piezo-electric transducer.  
           [0006]    The ultrasonic instrument includes a generator of ultrasonic energy; a connecting body that receives ultrasonic energy from the generator and has an end from which the energy exits. A coupler is provided at such end having an aspiration flow passage for receiving aspiration flow force from a source to remove emulsified material from an operating site. A work tip has its proximal end connected to the coupler to receive the ultrasonic energy from the connecting body and a distal end from which the ultrasonic energy is to be supplied to the operating site to emulsify material. The work tip has an aspiration passage that is in communication with the coupler aspiration passage with at least one of the work tip being detachable from the coupler and coupler detachable from the connecting body or the work tip and coupler detachable as a unit.  
           [0007]    In accordance with the invention, aspiration fluid flow force is provided through the coupler to the work tip aspiration passage without coming into contact with the interior of the connecting body. This permits removal of the work tip so that the instrument can be re-used by replacing the work tip and without sterilization of the connecting body.  
           [0008]    In one form of the invention the coupler is a body that has a first, proximal, end connected to the end of the connecting body from which the ultrasonic energy exits and a second end to which the proximal end of the work tip is connected. The coupler body has an inlet passage to receive aspiration flow force, such as from a suction type pump, and an aspiration passage in communication therewith that also communicates with the work tip aspiration passage when the work tip is connected to the coupler. Preferably, a sleeve, that can be mounted to the connecting body or other part of the instrument, is spaced from and surrounds the coupler body and a portion of the work tip.  
           [0009]    In one embodiment, there is a resilient sealing element between the exterior of the coupler body and the interior of the sleeve on each side of the coupler body inlet passage to define a first chamber between the sealing elements to which the aspiration fluid flow force is applied. Irrigation fluid also is supplied to the interior of the sleeve in the space between the resilient element closest to the work tip proximal end to pass in the space between the work tip exterior and the interior of the sleeve.  
           [0010]    In another embodiment, the aspiration flow force is applied through a tube directly connected to the coupler body inlet passage. In this embodiment a sleeve also can be used and irrigation fluid supplied to a chamber formed between the interior of the sleeve and a single sealing element distal of the coupler body inlet passage.  
           [0011]    In still a further embodiment of the invention there is a collar at the end of the connecting body from which the ultrasonic energy exits and a passage from the collar through the connecting body to the exterior of the connecting body. A flexile tube extends through the connecting body passage and has a first end exterior to the connecting body to receive the aspiration flow force and a second end having a part that opens into the collar. With the proximal end of the work tip fastened to the collar the work tip aspiration passage is in fluid flow communication with the tube to receive the aspiration fluid flow force that is applied to the work tip aspiration passage.  
           [0012]    In all of the embodiments the aspiration flow force does not come into contact with any part of the connecting body. Thus, the work tip alone or the work tip and coupler body can be detached and disposed of and the instrument reused without sterilization by using a new work tip and coupler body. In th embodiment using the flexible tube passing through the connecting body, the work tip and tube are removed and replaced.  
         OBJECTS OF THE INVENTION  
         [0013]    An object of the invention is to provide an ultrasonic instrument in which the work tip can be easily removed and no sterilization is needed for the connecting body.  
           [0014]    A further object is to provide an ultrasonic instrument in which aspiration flow force used for removing emulsified tissue from the operating site does no come into contact with the connecting body.  
           [0015]    Still a further object is to provide an ultrasonic instrument in which a coupler body is attached to the connecting body and aspiration flow force is provided through the coupler body to the work tip aspiration passage.  
           [0016]    Yet another object is to provide aspiration flow force through a tube passing through the connecting body to a work tip that is coupled to the connecting body. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    Other objects and advantages of the present invention will become more apparent upon reference to following specification and annexed drawings in which:  
         [0018]    [0018]FIG. 1 is a cross-sectional view of a prior art ultrasonic instrument;  
         [0019]    [0019]FIG. 2 is a cross-sectional view of a first embodiment of an ultrasonic instrument in accordance with the invention;  
         [0020]    [0020]FIG. 3 is a second embodiment of the ultrasonic instrument of the invention;  
         [0021]    [0021]FIG. 4 is a cross-sectional view of a third embodiment;  
         [0022]    [0022]FIG. 5 is a view of a further embodiment; and  
         [0023]    [0023]FIG. 5A is a view of a component used in the embodiment of FIG. 5. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0024]    [0024]FIG. 1 depicts one type of prior art ultrasonic handpiece as shown in U.S. Pat. No. 4,504,264. There is a casing  10  of, for example, plastic or metal, within which is supported a transducer means  11  for generating mechanical vibrations upon excitation with an alternating-current electrical signal. The transducer  11  preferably is a magnetostrictive transducer with an electrical coil  12  wound about each leg of a stack of metal laminations so that longitudinal mechanical vibrations are produced. There is a connecting body  16  of, for example, titanium, having a reduced diameter distal end portion, which also can be an attached separate portion. The connecting body  16  forms an acoustic impedance transformer for conveying the longitudinal vibrations of the transducer  11  for application to an operative tool or working tip  14  connected to the distal end of the connecting body  16 .  
         [0025]    The work tip  14  distal end is at least partially external of the casing  10  and is supported thereby and is connected, such as by a screw thread  27 , to the narrowed distal end of the connecting body  16  so as to be coupled to the transducer  11  to be longitudinally vibrated thereby. The working tip  14  is an elongated, hollow tip of a suitable metal, such as titanium, that is capable of supporting ultrasonic vibrations and has a distal end of a desired shape to be placed at an operating site against the tissue to be removed. The work tip  14  has a threaded proximal base portion  15  in engagement with the distal end of the connecting body  16  by a screw thread arrangement  27 . The tip  14  can be interchanged by use of the screw threads.  
         [0026]    The distal end of the tip  14  is shown surrounded by a sleeve  17 , such as of silicone, whose proximal end is supported in threaded engagement on a reduced diameter end  18  with the casing  10 . If desired, the proximal end of sleeve  17  can be engaged more proximally along the length of the casing  10  or mounted to the connecting body. The connecting body  16  has disposed thereon two elastomeric O-rings  19 ,  20  which provide fluid-tight seals between the connecting body  16  and the internal wall of casing  10 . A plurality of screws  51  are shown disposed around the axis of the casing  10  for preventing longitudinal displacement (other than vibrational) or rotational movement of the vibratory structure within the casing and also for radially centering the vibratory structure within the casing. Other types of conventional mounting arrangements can be used.  
         [0027]    The instrument also illustratively has electrical input terminals  40 ,  41  for applying a suitable electrical signal to the magnetostrictive transducer  11 . A cooling water inlet  42  and a cooling water outlet  43  for circulating cooling water inside the casing  10  in the region around the magnetostrictive transducer  11  and connecting body  13  are provided and are sealed by an O-ring  19  and by a fluid-tight grommet  50 .  
         [0028]    The sleeve  17  around the tip  14  forms a first fluid passage  21  between the tip  14  and the sleeve for irrigation fluid and an inlet is provided on the casing or sleeve for supplying the irrigation fluid to the passage  21  from a supply of fluid (not shown) that is preferably sterile. There is a passage  23  formed through the connecting body  16  that is in communication with a central (aspiration) passage  25  of the work tip  14 . An outlet  24  on the casing or sleeve receives a suction (aspiration) force that is applied to the passage  23  in the connecting body and the passage  25  in the work tip. A chamber  31  is formed between the spaced O-rings  19 ,  20  on the body  16  and the casing  10 , or sleeve, with which the aspiration force communicates. Thus the aspiration force is from the source, into the chamber  31  between the O-rings, through the passage  23  in the connecting body and the passage  25  in the work tip  14 . Tissue that is emulsified by the work tip is aspirated from the operating site by the aspiration flow force.  
         [0029]    Other apparatus (not shown) for the instrument includes a suction pump, a treatment fluid supply, an oscillator for applying an electrical signal to the vibratory structure and control apparatus therefore. All of these are of conventional construction.  
         [0030]    Considering now the operation of the instrument of FIG. 1, when an electrical signal having a frequency of, for example, 40,000 cycles is applied to the coil  12  around the magnetostrictive transducer  11 , the transducer  11  vibrates longitudinally at 40,000 cycles per second, thereby vibrating the connecting bodies  13 ,  16  and the working tip  14 . Treatment (irrigation) fluid is supplied through inlet  22  and fluid passage  21  to bathe the tissue in the operating site region around the working tip  14 . Suction flow (aspiration) force is applied through inlet  24  and connecting body passage  23  to the working tip  14  aspiration passage  25  to withdraw the tissue fragmented (emulsified) by the work tip as it vibrates.  
         [0031]    The instrument of FIG. 1 is not optimally adopted for single use of the work tip  14 . While the work tip  14  can be separated for changing or sterilization by unthreading it from the narrowed distal end of the connecting body  16 , a problem remains in that the portion of the aspiration passage  23  in the connecting body  16  still might not be sanitary. That is, a residue from a previous operation might remain in the aspiration passage  23 . Therefore, at the very least, the connecting body  16  should be sterilized before another operation is performed using the instrument. This requires time and effort and might not be a convenient procedure to performed at a particular time.  
         [0032]    [0032]FIG. 2 shows a preferred embodiment of an ultrasonic surgical instrument according to the invention in which there is no aspiration fluid flow passage in the connecting body and the work tip  14  can be more easily changed. The same reference numerals are used for the same elements present in FIG. 1. Here the distal end portion of the connecting body  16  is tapered and has an internally threaded recess  70  at its end. A threaded collar can be used as an alternative. A coupler body  72  is provided externally of the connecting body  16  that has a threaded stud  73  at its proximal end to screw into the connecting body threaded recess  70  and a threaded recess  75  at its distal end into which the threaded base  15  of the work tip  14  is screwed. The coupler  72  is of a suitable material, such as the same metal as the connecting body  16  and is shown as a generally cylindrical body. If desired, the coupler body outer surface can have flats or grooves to accommodate a wrench, spanner or other tool.  
         [0033]    Coupler  72  has a radial inlet aspiration flow force passage  76  between the stud  73  and recess  75 . The passage  76  preferably extends across the diameter of the coupler body. There is a longitudinal passage  78  whose proximal end communicates with the radial passage  76  and whose distal end communicates with the aspiration passage  25  in work tip  14  when the work tip base  15  is threaded into the coupler recess  75 .  
         [0034]    The instrument of FIG. 2 has a sleeve  80  whose proximal end is connected to a flange  16   a  on the connecting body  16 , such as by a threaded engagement or a snap-press fit with an O-ring  83  between the two members. Any other suitable type of connection can be used, such as mounting the sleeve to a case in which the instrument is mounted. All of this is conventional. The sleeve can be of any suitable material, such as a plastic. Sleeve  80  has a distal section  82  that surrounds, but is spaced from, the exterior of work tip  14  to establish the irrigation fluid flow passage  21 .  
         [0035]    The sleeve  80  has the aspiration force supply port  24  to which a suitable tubing (not shown) is to be connected to supply the force to remove the material from the operating site. Port  24  is positioned generally opposite the coupler radial passage  76 . There are a pair of O-rings  90  and  91 , one mounted on each side of the coupler radial passage  76 , between the exterior of coupler body  72  and the interior of sleeve  80 . If desired, circular grooves  89  can be formed on the outer surface of coupler  72  into which the O-rings  90 ,  91  can be fitted. Alternatively, grooves to hold the O-rings can be formed on the interior of the sleeve  80 . The O-rings  90 ,  91  provide a fluid tight seal between the interior of sleeve  80  and the coupler  72  on each side of the coupler radial passage  76  and form a chamber  79 . Thus, aspiration force supplied through the port  24  is applied to the work tip aspiration passage  25  and emulsified material removed through the chamber  79 , coupler radial passage  76  and the transverse passage  78 . The radial passage  76  illustratively is shown extending completely through the coupler so that there are two opposed entries into the chamber  79 . This increases the flow force that can be applied to remove the emulsified material. The radial passage  76  can extend only part way through the coupler  72  and terminate at the transverse passage  78 .  
         [0036]    As seen, there is no communicating passage from the tip aspiration passage  25  to the connecting body  16  since the proximal end of the coupler  72  is solid. That is, the aspiration passage does not extend through the connecting body. If desired, the confecting body  16  can have a passage for cooling fluid.  
         [0037]    An inlet port  22  for the irrigation fluid is provided on the sleeve  80  distally of the O-ring  91  and a chamber  93  is formed that communicates with the irrigation passage  21  surrounding the work tip  14 . As seen, the irrigation fluid chamber  93  is sealed from the aspiration fluid chamber  79  by the O-ring  91 . Irrigation fluid supplied through the port  22  to the chamber  93  flows through the tip irrigation passage  21  to the distal end of the tip  14  to be available at the operating site.  
         [0038]    In the embodiment of FIG. 2, the work tip is replaced by first detaching the sleeve  80  from the connecting body and removing it. This leaves the tip  14  and coupler  72  exposed. The tip  14  can be unthreaded from the coupler  72  and the coupler then unthreaded from the connecting body  16 . Preferably, the coupler  72  with the tip  14  attached is unthreaded from the connecting body  16 . As indicated above, if the O-rings  90 ,  91  are in grooves on the coupler  72 , then they would also be detached together with the coupler. The detached tip, and preferably also the coupler and O-rings, are then disposed of. It is also preferred that the sleeve  80  be disposed of since its interior forming the aspiration chamber  79  has been contacted by the material that was aspirated from the operating site. There is no need to perform any cleaning or sterilization for the connecting body  16 .  
         [0039]    [0039]FIG. 3 shows a further embodiment of the invention with a different type of coupler  172  in which the radial passage  176  extends only into the coupler for a distance sufficient to meet the transverse passage  78 . The sleeve  80  has an opening  182  of sufficient size to provide access to the coupler radial passage  176 . A flexible tube  151 , such as of a plastic material, that supplies the aspiration flow force has one end connected to the aspiration flow source (not shown). The other end has a headed end  153  with a nipple of a deformable material, such as a soft plastic, that is inserted into the opening of the radial passage  176 . The nipple of head  153  is press fit into the passage opening. If desired, a Leur or other suitable type of connector can be used to connect the tube  151  head  153  to the passage  176 . A direct flow path is established between the aspiration fluid flow source and the work tip aspiration passage  23  trough the tube  151  and passages  176  and  76  in the coupler  72 .  
         [0040]    In this embodiment, the sleeve  80  is not necessary since no chamber has to be provided for the aspiration flow force. Use of a sleeve is preferred so that the O-ring  91  is used between the coupler and the sleeve to establish the irrigation fluid chamber  93  that communicates with the work tip irrigation fluid passage  21 .  
         [0041]    The tip is removed in the manner described above with respect to FIG. 2 by first removing the sleeve  80  and then unthreading the tip from the coupler or, preferably by unthreading the coupler with the tip attached from the connecting body  16 . In this embodiment the aspirated material does not come into contact with the interior of sleeve  80  so that it is not necessary to dispose of the sleeve.  
         [0042]    [0042]FIG. 4 shows a modification of the coupler of FIG. 3. Here a duct  181 , such as a piece of tubing of a suitable material compatible with the coupler  172  is affixed to and extends outwardly from the coupler  172 . The duct  181  is accessible through the opening  182  in the sleeve  80 , if such sleeve is used. The flexible tube  151  has an enlarged reinforced head  183  that is fitted over the duct  181 . Aspiration flow force is provided to the aspiration passage  23  in the work tip  14  through the duct  181  and coupler passages  176  and  78 . The tip  14  is removed from the instrument in the same manner as described with respect to the embodiment of FIG. 3.  
         [0043]    While the couplers  72  and  172  of FIGS.  2 - 4  are shown as being separate from the work tip  14 , it should be understood that they can be made integral with the proximal end of the tip so that the tip and coupler can be removed as a unit.  
         [0044]    [0044]FIGS. 5 and 5A show another embodiment of the coupler that permits removal of the work tip. Here a threaded collar  191  is formed on the exterior of the narrowed distal end of the connecting body  16  to accept the threaded base  15  of the work tip  14 . A passage  205  is formed through the connecting body  16  that has one end  207  on the outer surface of the body  16  and a second end  208  that opens in the collar  191  opposite the entry to the aspiration passage  23  in the tip  14 . A flexible tube  201  of plastic material is provided that is of a diameter smaller than the connecting body passage  205  and has a washer, or flange, type head  203 .  
         [0045]    In use, the free end of tube  201  is passed into the collar  191  and through the end  208  of the connecting body passage  205  to exit from the body passage  207 . The washer type head  203  is pressed against the back end of the collar  191  against the connecting body. The free end of the tube  201  remote from the washer head  203  is connected to the aspiration flow source by any suitable type of connecting arrangement. When the base end  15  of tip  14  is threaded into the collar  191 , a seal relative to the tube  201  is formed with the washer head  203 . There is communication between the aspiration fluid flow source and the work tip aspiration passage  25  through the tube  201 . The sleeve  80  for the irrigation fluid is not shown but it can be as in FIG. 4.  
         [0046]    In use, the work tip  14  can be unthreaded from the collar  191  and disposed of. The tube  201  is then pulled out of the connecting body passage  205  and disposed of. The free end of the tube  201  can be sealed before the tube is pulled out of the connecting body passage so that there is no leakage of material from the tube as it is pulled from the body. Here also there is no contact of material removed from the operating site with any part of the connecting body  16 . Therefore, the connecting body does not have to be sterilized.  
         [0047]    While threaded connections have been shown between the work tip and the connecting body, it should be understood that other types of connections, such as a bayonet lock can be used.  
         [0048]    Specific features of the invention are shown in one or more of the drawings for convenience only, as each feature may be combined with other features in accordance with the invention. Alternative embodiments will be recognized by those skilled in the art and are intended to be included within the scope of the claims.