SINGLE-BLOW SHOCKWAVE GENERATION DEVICE
A single-blow mechanical shockwave generation device used in urological surgery for disintegration of urinary duct stones comprises a striking device which strikes a shock wave generation device at high speed. The shock waves are transmitted by a shock wave transfer device to an object for destruction with which the shock wave transfer device is in direct or indirect contact. The striking device is displaced by way of the expansion of a high-pressure gas introduced prior to each shock wave generation into an accumulation device. The accumulation device is supplied with high pressure gas from independent gas stores and with supply and sealing devices. The stored gas is released by the manual manipulation of a control device which connects the accumulation device to the striking device.
Latest LMA UROLOGY LIMITED Patents:
This application is a continuation application of, and claims priority from, pending prior application Ser. No. 10/545,107, filed Aug. 10, 2005 as the U.S. National Stage entry of International Patent Application No. PCT/FR2004/000208 filed Jan. 30, 2004, and claims priority under 35 U.S.C 119 of French Patent Application No. 03/01793 filed Feb. 14, 2003.
BACKGROUND OF THE INVENTIONThe invention refers to a single-blow shockwave generation device and its implementation process.
Shockwave generation devices are notably used in urological surgery for disintegration of urinary duct stones. The prior art includes two main types of shockwave generation devices: a first type concerning extra-corporeal shockwave generation devices, and a second type concerning percutaneous shockwave generation devices.
Disintegration devices of the first type use an electrical or piezo-electrical shockwave generator where the shockwave guide is comprised of a pocket containing a fluid, in contact with patient's body cooperating with an ellipsoidal reflector which receives a shockwave diffused into a wide space, to focus it through a widely open cone whose apex is located inside the urinary stone to be disintegrated, so that the shockwave is of low amplitude when it crosses through living tissues in order to reduce lesions to said tissues to the minimum possible extent, and of maximum amplitude when concentrated at cone apex.
Disintegration devices of the second type use, for example, specialized endoscopes to match the nature of the intervention to be performed, depending on the size and position of the urinary stone to be evacuated. When the stone is inside the kidney, the endoscope is introduced percutaneously directly into the kidney. When the stone is in the ureter, it is advisable to introduce the endoscope by natural paths via the bladder and up into the ureter. The shockwave is transmitted by a waveguide, which is a metallic rod of circular cross-section, of a diameter of ten to twenty tenths of a millimeter, and able to tolerate elastic deformation. The shockwave guide features a first end where the shockwave is generated and a second end which is applied against the stone.
Disintegration devices of the first type do not allow high amplitude shockwave production, due to risk of lesions to living tissues crossed through. Consequently, stone disintegration requires multiple shocks which reduce the stone into small fragments which can be evacuated through the urinary ducts.
Disintegration devices of the second type, notably that described in European patent EP0317507, use low amplitude shockwave trains whose characteristic feature is also to break the stone to be disintegrated into multiple fragments which can be eliminated by suction, washing, or evacuation through natural paths.
Disintegrated stone fragment elimination through natural paths is very painful, which makes elimination by washing preferable whenever possible, further to an intervention by endoscopy. These stone elimination modes feature a drawback, in that there always remains uneliminated stone debris which can act as a basis for new stone formation.
Gas sealing devices between moving parts in these devices generally include O-rings, for which sealing is obtained by cooperation, either between the higher and lower sealing circles of the O-rings pressed between two flat surfaces or through cooperation between an inner lateral sealing circle and an outer lateral sealing circle of the O-ring pressed between a revolution bore and a revolution cylinder. These sealing devices can be classified, for example, into three types of devices: a sealing device of the first type is comprised of an O-ring positioned in a groove machined in a bore and whose sealing is ensured by cooperation between the inner lateral sealing circle and the outer lateral sealing circle. A sealing device of the second type is comprised of an O-ring located in a groove machined in a revolution cylinder. A sealing device of the third type is comprised of an O-ring located in a circular groove undercut in a flat surface.
SUMMARY OF THE INVENTIONThe present invention relates to a wave generation device, generating a high amplitude wave transmitted either percutaneously or naturally, via an endoscope, permitting controlled fragmentation of the urinary stone in order to break it into a small number of fragments of the necessary and sufficient size to allow their manual extraction by way of tweezers through the endoscope which was implemented in order to visualize, seize and extract them.
The following description of the invention will be better understood by reference to the appended illustrations, in which:
The invention consists of a single-blow mechanical shockwave generation device (
The gas used can be assimilated to a perfect gas at operating temperature, which is approximately twenty degree Celsius, in an accumulation chamber, making up an accumulation device, and at operating pressure which is a high pressure of approximately fifteen to thirty bar, and chemically compatible with its intended utilization. For example, the gas can be air or nitrogen from a gas cylinder pressurized at a very high pressure of approximately two hundred bar, making up an independent gas store whose content can vary from half a liter to a few liters. It is connected to the single-blow mechanical shockwave generation device 1 via a flexible hose and through a pressure-relief valve. The hose and valve make up a pressure-relief device that is secured to the gas cylinder and which reduces the very high pressure from two hundred bar to a high pressure of fifteen to thirty bar.
In a preferred embodiment of the invention, the gas used is, for example, carbonic gas commercially available in a single-use gas micro-container 9 (
The gas micro-container 9 is comprised of a cylindrical body 10 whose outer diameter is approximately eighteen millimeters, and whose rear end 11 is closed by a hemispherical wall and front end 12 is extended by a stepped section, then by a neck 13 comprising a lateral part, essentially cylindrical, closed by a closing capsule 14. The stepped section and neck 13 assembly features a length of approximately thirteen millimeters and the total length of the assembly is approximately eighty millimeters. Gas micro-container 9 is directly integrated into single-blow mechanical shockwave generation device 1. It is housed into cradle 15 comprised of two half-cradles. Front half-cradle 16 is comprised of a revolution-cylindrical bore, along first symmetry axis 17, of a diameter slightly larger than that of gas micro-container body 9, and features a bottom section fitted with calibrated receptacle 18 which accommodates neck 13 of gas micro-container 9. The lateral part is equipped with a first sealing device of first type 19, with respect to the lateral part of neck 13, whereas the central part of calibrated receptacle 18 features a perforation device 20 which pierces closing capsule 14. Rear half-cradle 21 is comprised of holding device 22 for the hemispherical bottom section of gas micro-container 9, centered on the first symmetry axis 17, and capable of sliding, parallel to the latter, thanks to guide stir-up 24 and clamping device 23 which bears upon front half-cradle 16. The guide stir-up features wide lateral openings which allow sliding of front end 12 of gas micro-container 9 into calibrated receptacle 18 of front half-cradle 16, when the rear half-cradle 21 is retracted. It is only necessary to slide holding device 22 which comes against stop upon hemispherical bottom section 11, then to tighten by pushing gas micro-container 9 against perforation device 20 until closing capsule 14 is pierced. Perforation device 20 features a gas transfer device. Perforation device 20 is, for example, of the type used on single-use butane gas cylinders, and a gas transfer device is a central cylindrical bore 25 allowing circulation of the gas from micro-container 9. Perforation device 20 is intercommunicated, through a first duct 26, with pressure-relief device 27, integrated with single-blow mechanical shock with generation device 1, making up a gas pressure-relief device 7 (
The assembly comprised by first and second chambers 28 and 36, the gas supply valve, first piston 35, first and second calibrated springs 33 and 41, makes up a gas pressure-relief device 7 (
A third duct 42 (
A fifth duct 62 (
When second piston 45 is in the front position, the free end 55 of control rod 54 presses against the free end 77 of second pusher 76 and thereby pushes back valve head 67 and separates it from the bottom of rear section 63 of fourth chamber 64, by compressing the first helical spring 73, therefore releasing the opening of sixth duct 75. The fourth chamber 64 is intercommunicated through sixth duct 75 with fifth chamber 72. The fifth chamber 72 is of revolution-cylindrical shape, with a rear section 81, in which sixth duct 75 opens, and a front section 82 from which a fifth revolution-cylindrical bore 83 begins. The fifth bore 83 is preferably coaxial with the symmetry axis of fifth chamber 72. Fifth chamber 72 features a diameter slightly larger than that of valve body base 68, and a significantly smaller length. Fifth bore 83 (
Seventh chamber 90 (
Eighth chamber 101 contains a shockwave guide head 115 of a second shockwave guide device 114, revolution-cylindrical, of a diameter slightly smaller than that of eighth chamber 101, whose rear face 116 is flat-shaped and whose front face 117 is essentially flat-shaped and comprises, squarely secured at its centre, a shockwave guide rod 118 which passes through eighth bore 113 and which acts as guide for shockwave guide head 115 of the second shockwave guide device 114. When the single-blow mechanical shockwave generation device 1 (
When the gas pressure in second duct 30 (
Shockwave generation begins by operating of hinged lever 51 (
In an improved embodiment of the invention, third chamber 43 (
The single-blow mechanical shockwave generation device 1 can be used for disintegration of urinary stones and can have a fourth chamber 64 whose volume is preferably comprised between one and three cubic centimeters, as well as a striking hammer of a weight of approximately ten grams.
In an improved embodiment of the invention, and for applications other than that concerning urinary stone destruction, it is necessary to generate successive shockwave trains. For this purpose, between hinged lever 51 and first pusher 49, a successive shockwave triggering device is inserted. This triggering device is activated by operation of lever 51. This initiates the generation of several successive shockwaves, for example, in a number and at a pace predetermined by successive operations of first pusher 49, without requiring the releasing of hinged lever 51.
Claims
1. A single-blow (1) mechanical shockwave generation device comprising striking means (2) motioned by gases and hitting at high speed a shockwave generation means (3), said shockwave being transmitted by shockwave transfer means (4), which can be put in direct or indirect contact with an object to be disintegrated, wherein the striking means (2) are motioned by expansion of a gas under pressure of fifteen to thirty bar introduced, prior to each shockwave production, into store means (5) from independent gas storage means (6) under pressure of seventy to two hundred bar, via gas expansion means (7) and supply means (25, 26, 30, 42, 56, 62), and a first sealing means (19, 37, 46, 60, 70, 74, 80), the gas stored in the store means (5) being released by manual operating of control means (8) which, firstly, seals to gases, through a second sealing means (58), the intercommunication between the independent gas storage means (6) and the gas expansion means (7) on the one hand, and with the store means (5) on the other hand, then, secondly, intercommunicates the store means (5) and the striking means (2), such that return to of the striking means (2) to an initial position is ensured by the release of energy accumulated by mechanical energy store means (73, 96) in the course of production of the shockwave, and return of control means (8) to its initial position is ensured by the pressure of the gas which remained at the expansion means (7) and the corresponding supply means (25, 26, 30, 42).
2. A device as described in claim 1, wherein the independent storage means comprises a pressurized gas cylinder, the cylinder being connected to the single-blow mechanical shockwave generation device (1) by a pipe and comprising a pressure relief valve for reducing the pressure to an operation pressure.
3. A device as described in claim 2, wherein the gas is stored in a gas micro-container (9) which makes up the independent gas storage means (6), the independent gas storage means is directly integrated into the single-blow mechanical shockwave generation device (1) by means of a cradle (15) comprised of two half-cradles, including a front half cradle (16) comprising a bottom fined with a calibrated receptacle (18) with a perforation device (20), and a rear half cradle (21) comprised of a sliding support device (22), where the perforation device (20) is connected, via a first duct (26) to an integrated expansion device (27) which makes up the gas expansion means (7).
4. A device as described in claim 3, wherein the integrated expansion device (27) is comprised of a first chamber (28) into which a first duct (26) leads and from where leads a second duct (30) in which a valve shank (31) freely slides, the valve shank having a head (32) located in the first chamber (28), the head being pushed back by a first calibrated spring (33), such that a free end of the valve shank (31) is pushed by a first cylindrical piston (35) which acts as a pusher for the valve shank (31), while the first piston (35) which slides in a second chamber (36) is used as a guide for a second calibrated spring (41) which acts as a pusher for piston (35).
5. A device as described in claim 4, wherein the control means (8) is comprised of a third chamber (43) into which leads a third duct (42) from second duct (30), and in which slides a second piston (45) comprising a first pusher (49) which enables said piston to be pushed into third chamber (43) via a hinged lever (51), whereas the second piston (45) comprises a control rod (54) which features a free end (55) and which freely moves through a fourth duct (56) comprising a third sealing device of the second type (58) which blanks the fourth duct (56) upstream of a fifth duct (62) leading into fourth duct (56), when second piston (45) is pushed into the third chamber (43), such that the free end (55) which is engaged into a second bore (59) then abuts against the bottom (61) of said bore.
6. A device as described in claim 5, wherein the store means (5) is comprised of a fourth chamber (64) into which leads a fifth duct (62) including a pressure relief valve (65) consisting of a tubular valve body (66) which makes up a sixth duct (75), a hollow valve head (67) and a valve body base (68) which slides in a third bore (69) leading into a fifth chamber (72), the valve head (67) maintaining sealing thanks to a first helical spring (73) making up a mechanical energy store means, while valve head (67) comprises a second pusher (76) with a free end (77) which slides in a fourth bore (79) and leads into the bottom of second bore (59), whereas the free end (77) of second pusher (76) is pushed back by the free end (55) of control rod (54), when abutting on the bottom (61), and while second pusher (76) pushes back valve head (67), compressing first helical spring (73) and clearing the opening of sixth duct (75), thereby intercommunicating fourth chamber (64) with the fifth chamber (72).
7. A device as described in claim 6, wherein striking means is comprised of the fifth chamber (72) into which leads a sixth duct (75) and which intercommunicates with fifth bore (83) leading into sixth chamber (84) which comprises a decompression zone (85) leading into sixth chamber (84), and from which leads at least one seventh duct (87) connected to the atmosphere either directly, or through check valve (88), the fifth bore (83) acting as a guide and launch device for striking hammer (92), comprised of hammer body (93), third piston (94) which slides in fifth bore (83), striking head (95) which features a free end (107), a second helical spring (96) making up a mechanical energy store means which pushes on hammer body (93) in order to maintain third piston (94) depressed in fifth bore (83).
8. A device as described in claim 7, wherein the shockwave generation means (3) is comprised of a shockwave generator interface device (102) including an interface device (103) which slides in a seventh chamber (90), connected to sixth chamber (84) via a sixth bore (91), whereas the interface device body (103) comprises a strike anvil (105) which crosses through the sixth bore (91), the sixth bore (91) comprising a free end (106) located in the sixth chamber (84), and a first shockwave transfer device (109) with a free end (119), passing through a seventh bore (99) which connect the seventh chamber to an eighth chamber (101) inside which the free end (119) of the first shockwave transfer device (109) is located, said free end being kept in contact with the rear face (116) of a shockwave guide head (115) by a third helical spring (110).
9. A device as described in claim 8, wherein the shockwave transfer means (4) is comprised of a second shockwave guiding device (114) consisting of a shockwave guide head (115) located in an eight chamber (101), extended by a shockwave guide rod (118) sliding in an eight bore (113) which acts as a shockwave guide head (115) and leads to the outside.
10. A device as described in claim 1, wherein the gas is carbonic gas stored under a pressure of seventy to two hundred bar, wherein the pressure in the fourth chamber (64) is fifteen to thirty bar, and wherein the volume of the fourth chamber (64) is one to three cubic centimeters and the weight of striking hammer (92) is ten grams.
11. A method of fragmenting a urinary stone, the method comprising:
- generating a high amplitude wave by storing a gas at a storage pressure; expanding a portion of the gas such that it is at an operational pressure that is less than the storage pressure; accumulating a volume of the gas at the operational pressure; and actuating a control device, whereby a further accumulation of the volume of gas is temporarily prevented while the accumulated volume of gas generates the wave; and
- transmitting the wave to the urinary stone, whereby transmission of the wave to the stone fragments the stone.
12. The method of claim 11, wherein the gas is stored in a cylinder, the storage pressure is in the range of about 70 bar to about 200 bar, and the operational pressure is in the range of about 15 bar to about 30 bar.
13. The method of claim 11, wherein storing a gas at a storage pressure comprises arranging a sealing arrangement in a first position to couple a gas source to a gas storage device through an expansion device.
Type: Application
Filed: Dec 19, 2008
Publication Date: May 7, 2009
Applicant: LMA UROLOGY LIMITED (MAHE)
Inventor: ALAIN LEBET (Lausanne)
Application Number: 12/339,182
International Classification: A61B 17/94 (20060101);