SURGICAL INSTRUMENT, IN PARTICULAR PHACOEMULSIFICATION HANDPIECE

Abstract

The surgical instrument (10), in particular a phacoemulsification handpiece, is provided with a housing (12), an ultrasonic transducer (40) positioned in the housing (12), and a tool (46) which is operatively connected to the ultrasonic transducer (40) for the purpose of ultrasonic excitation. The ultrasonic transducer (40) has a sonotrode (56), a resonator (58) and a piezoelectric ceramic element (60) positioned therebetween. The sonotrode (56) and/or the resonator (58) has an aluminum alloy or consists of an aluminum alloy having a tensile strength greater than 400 N/mm.sup.2. The housing (12) can consist of plastic and has an inner housing part (16) made of plastic, in which the ultrasonic transducer (40) is positioned. Cooling openings (82) are formed in the plastic inner housing part (16) through which openings a rinsing fluid for cooling the sonotrode (56) or the ultrasonic transducer (40) flows, said fluid passing along between the outer housing part (14) and the inner housing part (16).

Claims

1-19. (canceled)

20. A surgical instrument, in particular a phacoemulsification handpiece, comprising a housing, an ultrasonic transducer arranged in the housing and a tool which is operatively connected to the ultrasonic transducer for the purpose of ultrasonic excitation, the ultrasonic transducer comprising a sonotrode, a resonator and a piezoceramic element arranged therebetween and the sonotrode and/or the resonator comprising an aluminum alloy or being made of an aluminum alloy, wherein the aluminum alloy has a tensile strength greater than 400 N/mm.sup.2.

21. The surgical instrument according to claim 20, wherein the aluminum alloy is a high-strength aluminum alloy.

22. The surgical instrument according to claim 20, wherein the aluminum alloy is an alloy selected from the group of the following aluminum alloys: Al—Cu4SiMg; AlCu4Mg1; AlZn4.5Mg1; AlZn5.5MgCu; AlZnMg3Cu; AlZn8MgCu.

23. The surgical instrument according to claim 20, wherein the sonotrode comprises a midsection arranged adjacent to the resonator, in which the sonotrode is supported in the housing, a rear end coupled to the resonator and a front end which is arranged opposite the resonator and is reduced compared to the midsection, the front end being operatively connected to the tool, and wherein a suctioning duct extends through the sonotrode from the front end thereof with to the rear end thereof with the rear end being connected to the resonator.

24. The surgical instrument according to claim 23, wherein the front end of the sonotrode comprises another metal material than aluminum or an aluminum alloy and in particular comprises titanium or iron or steel or an alloy comprising one of these metals, or wherein the front end of the sonotrode is made of another metal material than aluminum or an aluminum alloy and is made in particular of titanium or iron or steel or an alloy comprising one of these metals.

25. The surgical instrument according to claim 20, wherein the resonator is de-signed as a hollow cylinder and that the sonotrode has a rear end mechanically coupled to the resonator and extending through the resonator, said rear end is in mechanical engagement, in particular in threaded engagement with the resonator for the purpose of biasing the piezoceramic element arranged between the resonator and the sonotrode.

26. The surgical instrument according to claim 20, wherein the sonotrode at its front end operatively connected to the tool extends through an opening of the housing with a play, and that a holder element can be set, in particular plugged or screwed, on the housing at its opening, wherein an elastic sleeve extends from the holder element and surrounds the tool at its outer side.

27. The surgical instrument according to claim 20, wherein the tool is a hollow needle.

28. The surgical instrument according to claim 20, wherein the housing comprises plastic material and/or is made of plastic material.

29. The surgical instrument according to claim 20, wherein the housing comprises an inner housing part surrounding at least a portion of the sonotrode and an outer housing part between which an annular space is provided for supplying and/or for directing rinsing fluid to the tool.

30. The surgical instrument according to claim 20, wherein the inner housing part comprises cooling openings within which the sonotrode and in particular the midsection of the sonotrode is exposed and comes in contact with rinsing fluid for the purpose of cooling.

31. The surgical instrument according to claim 28, wherein the inner housing part comprises an exit opening for the front end of the sonotrode, and the outer housing part comprises an exit opening aligned with the exit opening of the inner housing part and spaced from the same in the longitudinal direction of the sonotrode, in which exit opening the front end of the sonotrode is arranged and/or beyond which the front end of the sonotrode protrudes and on which a holder element can be set, in particular plugged or screwed, from which an elastic sleeve extends from the holder element and surrounds the tool at its outer side.

32. The surgical instrument according to claim 31, wherein the annular space between the inner housing part and the outer housing part is adjoined at the exit opening of the inner housing part by a further annular space which is formed by the outer housing part and the front end of the sonotrode and which extends into an interspace defined by a play between the front end of the sonotrode and the exit opening of the outer housing part and, from there, transitions into an interspace between the tool and the elastic sleeve.

33. The surgical instrument according to claim 28, wherein the sonotrode comprises two axially spaced receiving grooves, each for one bearing ring, in particular for an elastic bearing ring and preferably an O-Ring, both bearing rings abutting on the housing from inside and in particular on the inner housing part for the purpose of supporting the ultrasonic transducer.

34. The surgical instrument according to claim 28, wherein the sonotrode comprises a receiving groove for a bearing ring, in particular an elastic bearing ring and preferably an O-ring, at its rear end opposite the front end or in its central portion, and wherein the front end of the sonotrode is centered by inwardly protruding ribs or the like protrusions of a connecting piece of the housing.

35. The surgical instrument according to claim 30, wherein the cooling openings are arranged in the region of the housing or the inner housing part situated between the two bearing rings and the two receiving grooves are formed in the midsection of the sonotrode.

36. The surgical instrument according to claim 28, wherein the housing comprises an inlet opening in fluid communication with the annular space for the supply of rinsing fluid.

37. The surgical instrument according to claim 28, wherein the housing has a passage opening for a suctioning hose at its rear end opposite the front end of the sonotrode, which hose is connected to the suctioning duct extending through the sonotrode.

38. The surgical instrument according to claim 28, wherein a connection cable connected to the piezoceramic element extends out from the housing.

Description

[0060] FIGS. 1 to 4 are different illustrations of a phacoemulsification handpiece 10 according to a first embodiment of the invention. The handpiece 10 comprises a housing 12 of plastic material. This housing has an outer housing part 14 and an inner housing part 16 arranged in the outer housing part 14. A first annular space 18 is formed between the two housing parts 14, 16, the inner housing part 16 being centrally supported relative to said annular space by a plurality of outer protrusions 20, 22. At the rear end 24 of the housing 12 the same closed by a single- or multi-part cover element 26 from which a suctioning hose is led out through a passage opening 28. Further, a connection cable 32 is led out from the cover element 26. These two components will be addressed further below.

[0061] As can be seen from FIGS. 1 to 4, the outer housing part 14 protrudes beyond the inner housing part 16 at the front end 34 of the housing 12. A connecting piece 36 is situated at the front end 34 of the housing 12, which connecting piece forms an exit opening 38 for an ultrasonic transducer 40 arranged in the housing 12. A holder element 42 is screwed onto the connecting piece 35, with an elastic sleeve 44 being located on the holder element, the sleeve surrounding a tool 46 in the form of a hollow needle 48 (with a lumen 49) of the handpiece 10.

[0062] Rinsing fluid flows into the annular space 18 of the housing via an inlet opening 50 to which a rinsing fluid hose 52 is connected, the fluid flowing from the annular space 18 into another annular space 54 and from there into the gap between the tool 46 and the elastic sleeve 44 via the exit opening 38.

[0063] The ultrasonic transducer 40 of the phacoemulsification handpiece 10, already addressed above, is located in the inner housing part 16 of the housing 12.

[0064] As can be seen in FIGS. 5 and 6, the ultrasonic transducer 40 comprises a sonotrode 56, a resonator 58 and at least one piezoceramic element 60. The connection cable 32 is connected to the piezoceramic element 50. A suction duct 62 extends through the sonotrode 56, which duct is in fluid connection with the lumen of the hollow needle 48 at the front end 64 of the sonotrode 56 and whose rear end 65 is provided with a connecting piece 66 for connecting the suction hose 30. The sonotrode 56 has a midsection 68 relative to which the front end 64 is reduced. The rinsing fluid flows through a gap 55 between the connecting piece 36 and the front end 64 of the sonotrode 50 (see FIG. 2) which is in communication with the tool 46, and flows further between the tool 46 and the elastic sleeve 44 which will widen correspondingly when the tool 46 is surrounded by rinsing fluid.

[0065] Opposite the front end 44 the sonotrode 56 has a rear endpiece 70 which is also reduced and which extends through the resonator 58 designed as a hollow cylinder with which it is in threaded engagement at 72. In this manner, the at least one piezoceramic element 60 can be held clamped between the resonator 58 and the midsection 68 of the sonotrode 56. The midsection 68 of the sonotrode is provided with two circumferential receiving grooves 74, each for one elastic bearing ring 76 via which the sonotrode 56 and thus the ultrasonic transducer 40 are supported in the inner housing part 16 of the housing 12.

[0066] The distinctive feature of the sonotrode 56 described herein is to be seen in the choice of its material. According to the invention a high-strength aluminum alloy is used which has a tensile strength greater than 400 N/mm.sup.2 and in particular greater than 450 N/mm.sup.2.

[0067] As can be seen in FIG. 1, the inner housing part 16 surrounds the midsection 68 of the sonotrode 56, as well as the piezoceramic element 60 and the resonator 58. In the region of the transition from the midsection 68 to the reduced front end 64 the sonotrode 56 protrudes from the inner housing part 16. The exit opening 78 provided in the inner housing part 16 is adjoined by the further annular space 54 which is defined by the outer housing part 14 and the reduced front end 64 of the sonotrode 56.

[0068] According to another aspect of the invention the housing 12 is a housing of plastic material. The sonotrode 56 is supported in the plastic inner housing part 16 via the two bearing rings 76. It is indicated at 80 in FIGS. 3 and 6 that the ultrasonic transducer 40 is pinned to the plastic inner housing part 16 in the region of its sonotrode 56. During operation of the ultrasonic transducer 40, the sonotrode 56 heats up noticeably, which is why it should be cooled. This is effected by the rinsing fluid, for which purpose the plastic inner housing part 16 is provided with a plurality of cooling openings 82 in the region around the midsection 68 of the sonotrode 56 (see FIGS. 3 and 4). Within these cooling openings 82, the midsection 68 the sonotrode 56 is exposed, so that the rinsing fluid can now flow directly along the sonotrode 56 in these regions, whereby the cooling effect is much more effective than in the case of a continuous design of the plastic inner housing part 16. Due to the fact that the rinsing fluid, which gets in contact with the tissue to be treated during an operation, flows along the sonotrode 56 in the midsection 68 thereof and in the reduced end 64 thereof (i.e. in the annular space 54), care should be taken that the material of the sonotrode is biocompatible. With an aluminum alloy and a rinsing fluid which is provided as a saline solution, this is possibly not given to a sufficient degree. Therefore, the sonotrode 56 should be provided with a biocompatible coating at least in the regions mentioned before. As an alternative, also the entire front end 64 of the sonotrode 56 can consist of a biocompatible metal such as titanium. This part of the sonotrode 56 would then be mechanically connected to the remainder of the sonotrode 56 e.g. by screwing.

[0069] As can be seen in FIG. 3, the bearing rings 76 are situated on either side of the array of cooling openings 83 and thus seal the sonotrode 56 in particular from the resonator 58 and the piezoceramic element 60, so that no rinsing fluid can reach this region.

[0070] As already mentioned above, the features of the invention and of the above-described embodiment, as far as they relate to the plastic housing, are an aspect of the invention that is independent of the other aspect of the invention, i.e. the use of special aluminum alloys for an ultrasonic transducer. The features of the plastic housing and individual variants thereof are listed in the following feature groups which may be combined with each other, but are also valid by themselves and define the invention and/or embodiments of the invention in all instances.

[0071] Referring to FIGS. 7 and 88, an alternative embodiment of the centric support of the sonotrode of in the housing of the handpiece will be addressed, which bears the reference numeral 10′ in these Figures. As far as the individual elements of the handpiece 10′ of FIGS. 7 and 8 correspond in structure or function to those of the handpiece 10 of FIGS. 1 to 6, they are identified in FIGS. 7 and 8 by the same reference numerals as in FIGS. 1 to 6.

[0072] The difference between both handpieces 10 and 10′ is to be seen in the support of the sonotrode 56. In the handpiece 10′, the sonotrode 56 is supported at its rear end 65 or in its midsection by the O-ring 76, whereas its front end 84 is centered at inward protruding ribs 84 of the connecting piece 36 of the outer housing part 14 (see FIG. 8). The ribs 84 protrude into the gap 55 and divide the same into individual ducts 86. Moreover, the ribs 84 stiffen the connecting piece 36 and thus the housing. The front receiving groove 74 of the sonotrode 56, which exists in the handpiece 10 of FIGS. 1 to 6, can be omitted which is advantageous in terms of production and assembly (the front O-ring and the assembly thereof to the sonotrode are omitted).

[0073] Individual embodiments of the invention can comprise one or a plurality of the following feature groups or individual or a plurality of one or a plurality of the following feature groups. [0074] Surgical instrument, in particular a phacoemulsification handpiece, comprising [0075] a housing 12 [0076] an ultrasonic transducer 40 arranged in the housing 12 and [0077] a tool 46 which is operatively connected to the ultrasonic transducer 40 for the purpose of ultrasonic excitation, [0078] the ultrasonic transducer 40 comprising a sonotrode 56, a resonator 58 and a piezoceramic element 60 arranged between these and [0079] the housing 12 comprising plastic material and//or consisting of plastic material. [0080] Surgical instrument, in which the housing 12 comprises an inner housing part 16 surrounding at least a part of the sonotrode 56 and an outer housing part 14 between which an annular space 18 is provided for supplying and/or for directing rinsing fluid to the tool 46. [0081] Surgical instrument, in which the inner housing part 16 comprises cooling openings 82 within which the sonotrode 56 and in particular the midsection 68 of the sonotrode 56 is exposed and comes in contact with rinsing fluid for the purpose of cooling. [0082] Surgical instrument, in which the inner housing part 16 comprises an exit opening 78 for the front end 34 of the sonotrode 56, and the outer housing part 14 comprises an exit opening 78 aligned with the exit opening 38 of the inner housing part 16 and spaced from the same in the longitudinal direction of the sonotrode 56, in which exit opening the front end 34 of the sonotrode 56 is arranged and/or beyond which the front end 36 of the sonotrode 56 protrudes and on which a holder element 42 can be set, in particular plugged or screwed, from which an elastic sleeve 44 extends that surrounds the tool 46 on the outer side. [0083] Surgical instrument, in which the annular space 18 between the inner housing part 16 and the outer housing part 14 is adjoined at the exit opening 78 of the inner housing part 16 by a further annular space 54 which is formed by the outer housing part 14 and the front end 34 of the sonotrode 56 and which extends into a gap 55 defined by a tolerance between the front end 34 of the sonotrode 56 and the exit opening 38 of the outer housing part 14 and, from there, transitions into a gap between the tool 46 and the elastic sleeve 44. [0084] Surgical instrument, in which the sonotrode 56 comprises two axially spaced receiving grooves, each for one bearing ring, in particular for an elastic bearing ring and preferably an O-Ring, both bearing rings abutting on the housing 12 from inside and in particular on the inner housing part 16 for the purpose of supporting the ultrasonic transducer 40. [0085] Surgical instrument, in which the sonotrode 56 comprises a receiving groove 74 for a bearing ring 76, in particular an elastic bearing ring and preferably an O-ring, at its rear end 65 opposite the front end 64 or in the central portion, and wherein the front end 64 of the sonotrode 56 is centered by inward protruding ribs 84 or the like protrusions of a connecting piece 36 of the housing 12. [0086] Surgical instrument, in which the cooling openings 82 are arranged in the region of the housing 12 or the inner housing part 16 situated between the two bearing rings and the two receiving grooves 74 are formed in the midsection 68 of the sonotrode 56. [0087] Surgical instrument, in which the housing 12 comprises an inlet opening 50 in fluid communication with the annular space 18 for the supply of rinsing fluid. [0088] Surgical instrument, in which the housing 12 has a passage opening 28 for a suctioning hose 30 at its rear end 24 opposite the front end 36 of the sonotrode 56, which hose is connected to the suctioning duct 62 extending through the sonotrode 56. [0089] Surgical instrument, in which a connection cable 32 connected to the piezoceramic element 60 is led out from the housing 12.

LIST OF REFERENCE NUMERALS

[0090] 10 (phacoemulsification) handpiece [0091] 10′ (phacoemulsification) handpiece [0092] 12 housing [0093] 14 outer housing part [0094] 16 inner housing part [0095] 18 annular space [0096] 20 outer protrusions [0097] 22 outer protrusions [0098] 24 (rear) end of the housing [0099] 26 cover part [0100] 28 passage opening [0101] 30 suctioning hose [0102] 32 connection cable [0103] 34 (front) end of the housing [0104] 36 connection piece [0105] 38 exit opening for the sonotrode at the outer housing part [0106] 40 ultrasonic transducer [0107] 42 holder element [0108] 44 elastic sleeve [0109] 46 tool [0110] 48 hollow needle [0111] 49 lumen of the hollow needle [0112] 50 inlet opening [0113] 52 rinsing fluid hose [0114] 54 annular space [0115] 55 gap between the connecting piece and the front end of the sonotrode [0116] 56 sonotrode [0117] 58 resonator [0118] 60 piezoceramic element [0119] 62 suctioning duct [0120] 64 frontend of the sonotrode [0121] 65 rear end of the sonotrode [0122] 66 connection piece [0123] 68 midsection [0124] 70 endpiece [0125] 72 threaded engagement between the sonotrode and the resonator [0126] 74 circumferential receiving grooves [0127] 76 bearing ring [0128] 78 exit opening for the sonotrode at he inner housing part [0129] 80 pinning [0130] 82 cooling openings [0131] 84 (guiding and stiffening) ribs [0132] 86 ducts