FR2474304A1 - Instrument for pneumatic removal of live tissue e.g. tumour - has hollow handle and shaft with articulated tip directing pressurised fluid at tissue - Google Patents

Abstract

The surgical instrument has a stem whose axis is fixed longitudinally w.r.t. the handle. The tip (76) of the instrument is mounted on the stem by a cylindrical element (100) which has radial slots (110) spaced angularly around its internal face. The connector permits axial movement of the tip relative to the stem when it is subjected to fluid pressure. The tip itself is essentially cylindrical with a radial flange (94). The tip has a central passageway opening at its distal end through which high pressure oxygen or air exits to sever the tissue. The flow of the pressurised fluid is controlled by a valve arrangement in the handle.

Description

 The present invention relates to tissue separators and more specifically to a pneumatic tissue separator intended to direct a suitable fluid, for example nitrogen gas under pressure, towards layers of tissue to be separated, with a controlled pressure, via of an orifice or a nozzle, having a controlled direction, as well as a method of implementing this device for the projection of a suitable fluid at controlled pressure and in a regulated direction, through an orifice and towards fabrics to be separated.

 Hitherto, mainly for the separation of tissues such as the membranes or pockets of the tumors from the healthy tissue placed around it, cutting devices and / or high-frequency vibratory structures have been used. Cutting devices such as scalpels have sometimes caused unwanted tissue damage and bleeding. High frequency vibrating heads often have annoying flexible connections to nearby generators with electrical energy inputs, and they are very expensive.

All of these known devices require a great deal of care and their handling during use is delicate so that the damage to the separated tissues is minimal.

 In its simplest form, the invention relates to a tissue separator having approximately the size of a writing felt and comprising a mechanical feeler end intended to physically palpate the tissue to be separated and thus to ensure separation. In an advantageous embodiment, the apparatus is a pneumatic tissue separator in which a gas suitable for a controlled pressure passes through a calibrated orifice with a floating end, in directions adjusted variously so that layers of tissue are quickly separated and with precision, without deterioration of the separated tissues or membranes. The end of the pneumatic separator according to the invention floats on gas cushions in equilibrium so that the pressure applied by the floating end forming a probe is limited.

 In an elaborate embodiment of a pneumatic tissue separator, the nitrogen gas pressure is variably regulated and the gas can be transmitted to the floating end using at least two separate controls which can be moved either by the thumb of the surgeon either by his index finger. In a variant of the pneumatic separator according to the invention, the gas used for the separation of the tissues and flowing through the calibrated orifice of the floating end is regulated by the surgeon's index finger while a humidification fluid circulates around the floating end of the separator and is adjusted by the thumb of the doctor. In another variant of the separator, the gas used for the separation of the tissue and flowing through the calibrated orifice of the floating end is regulated by the index of the surgeon while excess fluids present in the area of the separated tissue can be removed backward by suction around the floating end of the separator under the thumb of the surgeon.

 According to the method of the invention, the tissue to be separated is physically palpated by a rounded end fixed to the assembly comprising a body and a tissue separator rod; In an advantageous embodiment, the tissues are separated by nitrogen gas flowing in a floating end of the pneumatic separator, this end can also be used to feel the separated tissue, at a regulated and balanced pressure of the gas. In another variant of the process, a humidifying fluid can pass to the separated tissue at the same time as the physical probing and / or the transmission of gas to the separated tissue, or the fluid can be removed from the region of the separated tissue by placing implementing the method of the invention, at the same time as the separation is carried out.

Other characteristics and advantages of the invention will emerge more clearly from the description which follows, given with reference to the appended drawings in which
- Figure 1 is an elevation with parts cut away from a tissue separator according to the invention, intended for the implementation of the method of the invention
- Figure 2 is a partial elevation of a variant of the tissue separator of Figure 1, this figure representing an end making an angle with the longitudinal axis of the separator
- Figure 3 is an elevation with parts cut away from a pneumatic tissue separator according to the invention, intended for the implementation of the method of the invention
- Figure 4 is an enlarged section of a floating end for the separator of Figure 3
- Figure 5 is an enlarged section similar to Figure 4, showing a floating tip variant
- Figure 6 is a block diagram of a hydraulic circuit for an apparatus according to the invention having dental applications
- Figure 7 is an elevation of a more elaborate embodiment of a pneumatic tissue separator according to the invention, intended for the implementation of the method according to the invention
- Figure 8 is an enlarged section of the separator rod of Figure 7, along line 8-8
- Figure 9 is a partial elevation of a variant pneumatic tissue separator of the type shown in Figure 7, having a straight rod
- Figures 10A and 10B together form an enlarged section of part of the pneumatic separator of Figure 7
- Figure 11 is an enlarged longitudinal section of the end of the rod, the floating end and the end retaining device of the pneumatic separator of Figures 10A and lOB
- Figure 12 is a section through the floating tip and its retainer, shown in Figure 11, along line 12-12
- Figure 13 is a longitudinal section analogous to Figure 11 but showing a variant of floating tip and retaining device
- Figure 14 is a section through the variant end and retainer of Figure 13, taken along line 14-14
- Figure 15 is an enlarged section of the valve assembly of the pneumatic separator of Figures 10A and lOB, along line 15-15
- Figure 16 is an enlarged partial section of the valve assembly of the separator of Figures 10A and LOB along line 16-16 of Figure 15
- Figure 17 is an enlarged section of the valve assembly of the separator of Figures 10A and lOB, along line 17-17
- Figures 18A and 18B together form a longitudinal section of a variant of pneumatic tissue separator of the type shown in Figures 10A and lOB; and
- Figures 19A and 19B together form a longitudinal section of another variant of the pneumatic separator of Figures 10A and lOB.

 As indicated in FIG. 1, the simplest embodiment of a tissue separator according to the invention is a mechanical separator or feeler 10 having a hollow handle 12, a rod 14 fixed to the handle 12 by a device 16 rod retainer and a tip 18 and a tip retainer 20. An end cap 24 is mounted on the hollow handle 12 as shown.

 The hollow handle 12 has a generally cylindrical shape and cavities 26 and 28 for accommodating the thumb and forefinger. The end cap 24 is fixed to the handle 12 in any suitable manner, for example by a thread 30. Similarly, the rod 14 is fixed to the handle 12 by the retaining device 16 which has a radial flange 32 cooperating with a radial flange 34 of the rod 14. The retaining device 16 is fixed to the end of the handle 12 by any convenient device, for example by the thread 36 shown in FIG. 2. FIGS. 10A and lOB represent a example of structure using O-rings and ensuring friction mounting.

 The end 18 has a thread 38 at its internal end and it has a rounded external end 40. In a variant, the end 18 can be force-fitted. When the tip and the rod are made of plastic, the press fitting can be improved by ultrasonic welding. The rounded outer end 40 is intended to gently repel the fabric to be separated so that it spreads.

The end retaining device 20 has tapped cavities 42 and 44 at its opposite ends, so that it can cooperate with the threaded end 38 of the end 18 and the threaded projection 46 of the end of the rod 14.

 In use, the separator 10 is held by the handle 12 by a surgeon whose thumb is placed in the cavity 26 and the index finger in the cavity 28, and the tissue to be separated is gently pushed by the rounded end 40 tip 18.

 The assembly of the rod 14, of the retaining device 20 and of the tip 18 can form a lost assembly, to be discarded after use, that is to say after a single surgical use.

 In addition, as clearly indicated in FIG. 2, the rod 14 can be folded back so that it facilitates cooperation with the tissues of the rounded end 40, the surgeon then having a better view. As shown in Figure 2, the axis 50 of the tip 18 can make an angle which is for example 600 with the axis 48 of the rod 14. This particular angle of 600 is however not essential but we note that 'it is particularly useful. In addition, although the rod 14 is preferably folded so that it rises when the separator 10 is used, it can be folded and / or rotated around its axis in any desired direction.

 In this regard, it should be noted that the rod can be formed from an elastic, flexible or maL <eable material and can be bent at will. Thus, the rod can be formed from stainless steel, plastic or aluminum if desired.

 In the variant of pneumatic separator 52 of FIG. 3, a pressurized fluid is transmitted to the hollow handle 56 by the fitting 58 carried by the end cap 59 and by the flexible conduit 60 which is connected to a reserve not shown d 'a fluid having a predetermined pressure. In addition, the rod 62, the end 64 and the device 66 for retaining the latter, in the separator 52, have axial passages 68, 70 and 72 which are axially aligned and which receive the fluid from the hollow handle 56.

 Thus, when using the separator 52, the pressurized fluid which can be, for example, nitrogen gas or another fluid which is not harmful to the tissue being separated and to its vascular system, is used at pressures chosen to the separation of tissues such as tumor pockets, from the healthy adjacent tissue, the fluid being blown through the end of the tip 64 on the tissue, at the interface of the tissues to be separated. The separation of the tissues can also be facilitated by a slight push applied by the rounded end 74 of the end 64.

 In a more elaborate pneumatic separator as shown in FIGS. 4 and 5, the tip 76 floats on a cushion of fluid so that the pressure which can be applied during mechanical pushing by the rounded tip 78 is adjusted with the pressure of the fluid.

 As indicated in FIG. 4, the end 80 of the variant of rod 82 has a threaded extension 84 as described above and an axial passage 86 is formed in rod 82 and communicates with a reserve of pressurized fluid. A cavity 88 is also formed at the end 80 of the rod 82.

 The end 76 has a generally cylindrical shape and its internal end 90 is placed in the cavity 88 so as to be able to move there axially, the end 90 having an axial cavity 92 as shown. The other end 78 of the end 76 forms a rounded fabric separator as indicated above. An annular radial flange acting as a piston 94 is placed in the center of the end 76 as shown.

 A calibrated radial passage 96 is disposed between the cavity 92 formed at the end 90 of the end 76 and the external face of this end, as shown. An additional axial passage 98 or a calibrated orifice passes through the rounded external end 78 of the end 76. Diameters which are particularly useful for passage 98, for fluid pressures between 0.25 and 1.75 bar, are equal to 0.4, 0.64 and 0.8 mm.

 The end retention device 100 has a generally cylindrical shape and a tapped internal end 102.

The external end 104 ends in a rounded flared ring 106 projecting inwards, practically aligned in radial direction on an annular groove 108 of the end 76. Several slots arranged radially and axially 110, angularly separated, are arranged around the internal surface of the retaining device 100 as shown in Figure 4 so that the pressurized fluid can pass around the annular flange 94 of the tip 76 and so that it can float on the fluid used.

 The facing flat surfaces 95 and 97 of the end retaining device 100 facilitate the mounting and dismounting of this device 100 on the rod 82.

 When using a pneumatic tissue separator of the type shown in FIG. 3, having a floating end 76 as indicated in FIG. 4, the fluid circulates in the passage 86 then in the cavity 88 and in the cavity 92 then escapes radially through the passage 96 and the slots 110 so that it exerts a force tending to push the end 76 to the right in FIG. 4, this force being equal to the force due to the pressure acting on the surface of the end 90 of end 76 and at the pressure applied to face 112 of the annular surface or of the annular flange 94.

 This force is counterbalanced by the pressure of the fluid acting on the side 114 of the annular flange or piston 94 and by the pressure applied to the end 78 of the tip 76 due to the physical thrust applied by the tip 76 ensuring the separation of the tissues and / or by a back pressure which may appear at the end 78 of the end 76 due to the outlet of the pressurized fluid through the calibrated orifice 98 of the end 76.

 The passages 96 and 98 and, to a lesser extent, the sections of the slots 110 and of the ring formed between the groove 108 and the ring 106 determine the load for which the tip 76 comes back when pressed against a fabric, due to the gas cushion formed between the fabric and the rounded tip or when pushed directly into physical contact with the fabric. For this reason, it has been called "floating tip". Thus, all the predetermined factors fix the load applied to the end 78 of the end 76 which causes the withdrawal of the end and the movement to the left in FIG. 4. For example, for a nozzle orifice of 0.79 mm, the thrust load can be as low as 0.04 N, for a pressure of 0.56 bar.

 It should be noted that the movement to the right of the end 76 is limited by the ring 106 of the retaining device 100 while the movement to the left of the end 76 is limited by the external surface 116 of the end of the rod 82.

 In addition, it should be noted that, in the particular floating tip structure of FIG. 4, the fluid exiting through the calibrated orifice 78 forms a thin brush of relatively high pressure fluid intended to separate the tissues while a ring of fluid at lower pressure is formed between the end 106 of the retaining device 100 and the annular groove 108 around the rod 76.

The reduced pressure ring is particularly useful for constant cleaning of the neighboring region of the separated tissues.

 The variant floating-end structure shown in FIG. 5 is similar in many respects to that of FIG. 4, with the exception of the axial passage 98 which is eliminated from the end 109 of the end 111.

In the structure of FIG. 5, the separation of the tissues can be ensured by mechanical thrust of the tissue to be separated by the end 109 of the end 111, the physical thrust being limited by the floating pressure applied to the end 111.

This limitation of the pushing pressure due to the floating tip prevents injury to the tissue being separated.

 Although the structure of Figure 3 is advantageously intended for the separation of tissue, in particular with the floating ends of the type shown in Figures 4 and 5, other applications are possible.

For example, the structure of Figure 3 can be used by dentists or others for cleaning the teeth and the spaces between the teeth. In this application, as shown in FIG. 6, a flexible conduit 60 can be connected to a supply of pressurized water, for example a normal mixer 118 hot and cold mixes, either directly if necessary, or as shown in the figure 6, via a water pressure regulator 121 and / or a device 122 intended to form a pulsed stream of water. When the structure of FIG. 3 is thus connected, the water under pressure leaving the tip 72 or preferably the floating tip 76 of FIG. 4, when it is directed towards the teeth and the gums, can be used for entraining food particles and the like which can accumulate undesirably on the teeth and gums. The floating tip literally overlaps the teeth following their profile.

 The pneumatic separator 120 of FIGS. 7 to 17 is more elaborate than that of FIGS. 3 to 6. As indicated in FIG. 7, the separator 120 comprises an assembly 124 forming a body and having a sub-assembly 126 pressure regulator and a sub- 128 distribution set.

A valve assembly 130 is mounted between the rod 134 and the distribution sub-assembly 128. The rod 134 is fixed to the valve assembly 130 by a rod retaining device 136, and a floating end 138 is connected to the rod 134 by a retaining device 140.

 The rod 134 which can be of the lost type, has an axial passage 142 intended for the passage of the fluid towards the end 138, a parallel passage 144 intended for the circulation of the fluid towards the end 138 or withdrawn from the vicinity of this end 138, as indicated hereinafter in this specification being offset radially. In addition, as shown in FIG. 9, the rod 148 may be straight or its end 143 may be inclined relative to the longitudinal axis 146 of the pneumatic separator 120, as indicated above.

 The hollow external cylindrical member 244 of the distribution subassembly 128, as clearly indicated in FIGS. 10A and lOB, contains a threaded flange 246 turned inwardly forming a stop 248 on which the end 234 of the internal cylinder 210 is supported. The other end of the external cylinder 244 is tapped at 250 and cooperates with the threaded end 222 of the body 160 of the pneumatic separator 120. An O-ring 254 is mounted between the body 160 and the external cylindrical member 244, as shown.

 For the sake of clarity, reference 148 has been given to the straight rod in FIG. 9, in order to distinguish it from rod 134 having an inclined end 144. All the other numerical references in FIG. 9 are the same as those in FIG. Figure 7 and correspond to the same organs, having the functions described.

 As shown in more detail in Figures 10A and 10B, the body pressure regulator sub-assembly 126 has a structure 150 of pressurized fluid inlet, a pressure adjustment structure 154, a structure 156 forming a variable indicator for the pressure adjustment structure 154, a fluid outlet 158 and a fluid pressure tap 152 of the regulator, all these elements being fixed to or forming part of the body 160, the body being cylindrical and having the configuration shown in the figures 10A and lOB, in longitudinal section. The pressure tap 152 which has a threaded orifice 174 and a plug 168, allows the introduction of a pressure inspection device or a device intended to visually display the regulated pressure, if applicable, so that it is available to the surgeon. The plug can also be used for the manufacturer to calibrate the pressure regulator 154 and the indicator 156 which are incorporated as indicated in the remainder of this specification.

 As shown in FIGS. 10A and 10B, the fluid inlet structure 150 has a cavity 162 formed in the body 160 and having a tapped external end 164 intended to accommodate a flexible conduit 166 which forms an umbilical cord transmitting a fluid such as nitrogen gas under pressure, inside the separator 120.

The gas coming from an externally regulated reserve has for example a pressure of 3.5 bars at the level of the inlet structure 150.

 The pressure regulator adjustment structure 154 comprises an annular diaphragm 176 having a needle 178 which is fixed on it and which doses the quantity of fluid transmitted by the orifice 180 formed in the shutter 182. As indicated, the position of the needle 178 is adjusted according to the return force of a spring 181 and of an adjustment spring 184 which acts on the opposite ends of the needle 178, by means of a mechanical connection structure.

 Thus, depending on the axial position of the needle 178 in the orifice 180, the pressure of the fluid coming from the chamber 172 decreases in a controlled manner when it arrives in the chamber 186 and the fluid then passes into the subassembly 128 of distribution by the passage 188 formed in the body 160. For example, one obtains and uses in the chamber 186 a regulated pressure of the order of 0.21 to 2.45 bars.

 The pressure in the chamber 186 can also be transmitted to the distribution sub-assembly 128 through the passage 190, in the sub-assembly 126, if necessary, in different embodiments of separator 120 as described below. Thus, the plug 194 can be placed in the passage 190 or not depending on whether the pressurized fluid must reach certain locations or not and in the floating end which has certain characteristics as described in the remainder of this specification.

 The variable pressure indicator 156 comprises the rotary end cap 200 which carries the indicator point 202. This point 202, in cooperation with the graduations 204 carried by the cylindrical member 206 fixed to the body 160, indicate the exact pressure transmitted by the structure 154 for adjusting the pressure in the chamber 186.

Thus, a pressure of 3.5 bar for example in chamber 172 can be reduced to 0.35 bar or less in passages 188 and 190, and the value of the pressure is indicated by the graduations 204 and the position of point 202 on the rotary cap 200 and by the number of rotations of the cap 200. As indicated above, the calibration can be carried out using a pressure gauge placed in the threaded orifice 174 of the pressure tap 152.

 Thus, for a first rotation of one revolution of the cap 200, the external scale is used with the point 202 so that it gives a pressure reading in the chamber 186 which can reach 1.25 bar. During the next round, the central graduated scale is used with point 202 so that it gives an indication of the pressure of chamber 186, and so on for the number - # allowed for turns of the cap 200. The pressure in the chamber 186 can therefore vary as a function of the angular position of the cap 200 over several turns, two in general.

 The sub-assembly 128 represented in FIGS. 10A and lOB is disposed between the sub-assembly 126 forming a regulator and the valve assembly 130 as shown in FIG. 7. The distribution part 128 is separated by the cutting line, the connection being indicated by axis 208.

 More specifically, the distribution sub-assembly has an internal cylinder 210 having an axial passage 212. In addition, the cylinder 210 has a passage 214 and a groove 216 on the external surface of the internal cylinder and disposed longitudinally over practically the entire length if although a second fluid passage is formed in cooperation with the external cylinder 244 described below.

 The fluid flows to the valve assembly 130, through the passages 214 and 216, while a fluid at a different pressure or a humidification liquid can be transmitted through the central passage 212, or a fluid coming from the fabric. separated can be removed through the passages 212 so that it is extracted from the separator 120 by the outlet structure 158.

 As indicated in FIGS. 10A and 10B, the reduced diameter end 218 of the internal cylinder 210 of the sub-assembly 128 is placed in the cavity 220 formed at the end 222 of the body 160 of the sub-assembly 128. An annular groove 224 is formed on the external face of the internal cylinder 210 at the end 218 thereof so that it circumferentially distributes the fluid of the passage 190 and ensures the transmission of the fluid in the passage 214, coming from the passage 190, whatever or the relative angular position of the internal cylinder 210 and the body 160. O-rings 226 and 228 are placed annularly around the end 218 of the internal cylinder 210, in grooves 230 and 232 formed on the opposite sides of the annular cavity 224 , as shown in figures ZOA and lOB.

 The end 234 of the internal cylinder 210 of the sub-assembly 128 has a cavity 236 around which is formed the internal annular groove 238 in which the O-ring 240 is housed as shown in FIGS. 10A and lOB.

 The hollow external cylindrical member 244 of the subassembly 128, as clearly indicated in FIGS. 10A and lOB, carries the internal threaded flange 246 which forms a stop 248 on which the end 234 of the internal cylinder 210 is supported. The other end of the external cylinder 244 is tapped as indicated by the reference 250 and cooperates with the threaded end 222 of the body 160 of the separator 120. An O-ring 254 is placed between the body 160 and the external cylindrical member 244 as shown.

 The valve assembly 130 shown in FIGS. 10A and 10B comprises the member 256 forming a body and which has a substantially cylindrical shape. The end 258 of the body 256 has an O-ring 260 housed in an annular groove 262. The end 258 of the body 256 has an annular groove 264 ensuring the communication of a fluid under pressure between the passages 214 and 286. The body of The valve assembly is fixed to the external cylinder 254 of the distribution structure 128 by the threaded end 266. An O-ring 268 is placed between the body 256 and the external cylinder 244 of the subassembly 128.

 The other end 270 of the body 256 has a thread 272 and a cavity 274 as shown. An annular groove 276 is formed around the outer face of the end 270 of the body 256 as shown and a sealing ring 278 is housed therein.

 An axial passage 280 is formed in the body 256. In the variant of pneumatic separator 120 of FIGS. 10A and lOB, the passage 280 has a plug 282 at the end 258 of the body 256, as shown.

The body 256 of the valve assembly further has a passage 284 disposed axially and offset radially with respect to the passage 280. In addition, passages 286 and 288 are formed in the body 256 and are disposed between an annular groove 264 and the Cavity 298 for valve housing and between this and the annular cavity 292 surrounding the passage 280, as shown,
Valves 294 and 296 are housed in the cavities 290 and 298 between the passages 286 and 288 and in the passage 284 as shown. The valves are similar and they are better represented in FIGS. 15, 16 and 17. The valves 294 and 296 can be formed from a suitable plastic material, having an advantageously low coefficient of friction, for example "Teflon" which can be autoclaved, or "Delrin" which cannot undergo such treatment but which can be sterilized chemically or in another way.

 As indicated, the valve 294 has a head 300 having a cap 302 of plastic material which covers it and annular grooves 304 intended to prevent the sliding of the fingers of a surgeon, the rod 306 of the valve starting from the head 300 and housed in the cavity 290. The rod 306 has an annular dosing cavity 308 placed around as clearly shown in FIG. 16, and it has several sealingly closed bearing surfaces 310, between the groove 308 and the head 300 as indicated in FIG. 16 If necessary, a seal 312 is placed between some of the spans 310.

 The end 314 of the rod 306 has a cavity 316 intended to accommodate the spring 318 placed between this cavity 316 and a similar cavity 320 of a bottom member 322 in the form of a cup. The spring 318 pushes the rod 306 out of the cavity 298.

 The rod 306 is held in the cavity 298 by a pin 324 placed in the slot 326 formed in the rod 306. The length of the slot 326 is equal to the length of the path of the valve 294. The pin 328 is intended to retain the cup-shaped spring retainer 322 in cavity 290.

 As shown in Figures 15 and 17, the passages 290 and 298 pass completely through the body 256 and the through holes of the pins 324 and 328 are placed symmetrically in the passage so that the valves 294 and 296, in particular the valve 296 , can be turned over, that is to say placed on the other side of the body 256 so that the pneumatic separator can be used by a left-handed surgeon.

 Thus, during the operation of the valve structure 294, when the rod 306 is pressed in spite of the force exerted by the spring 318, the annular groove 308 for metering is aligned with the passage 284 and allows the fluid to circulate in the assembly 130 and in passage 284.

 Similarly, when the rod 330 is moved to the left in FIG. 17, the metering groove 332 is aligned with the passages 286 and 288 so that the fluid passes from the passage 286 to the passage 288.

 As clearly indicated in FIGS. 15 and 17, the passages 284 on the one hand and 286 and 288 on the other are offset radially relative to the central passage 288 and are angularly offset around the longitudinal axis 146 of the separator 120 of 90 . For reasons of economy, the passages formed in the body and the metering assembly 256 are represented in the same plane in the longitudinal section of FIGS. 10A and lOB, and consequently, in this section, they are not shown in position. suitable.

 As indicated previously, the rod 134 of the separator 120 can be of the lost type, used for a single surgical operation after which it can be discarded. Obviously, in a variant, the rod 134 can be formed of a suitable material such as "Teflon" which can be placed in the autoclave or in another sterilization atmosphere so that it can be reused several times, as indicated previously. In addition, the rod 134, as also indicated, can have any desired length and can be of any rigid material such as stainless steel, or elastic, flexible or badly leasable such as steel, plastic or aluminum. - minimum.

 The end 340 of the rod 134, having the indicated shape, is placed in the cavity 274 of the body 256 of the valve assembly with rings 342 and 344 of sealant housed in the grooves 346 and 348.

 As shown, the rod 134 has the radially offset passage 144 which passes through it and the axial passage 142. The passage 144 communicates directly with the passage 280 of the valve assembly 130 while the passage 142 communicates with the passage 284 of the assembly 130 by the annular space 354 delimited by the flared surface 356 formed at the end 340 of the rod 134.

 The rod 134 is fixed to the assembly 130 by the rod retaining structure 136. This structure 136 comprises the annular flange member 358 having the axial section shown in FIGS. 10A and lOB, and the clamp 360 at C. During assembly, the annular member 358 is slid over the rod 134 and comes into abutment against the annular flange 362 of the rod 134 so that the latter is fixed against the end face 364 of the body 256, when the member 358 cooperates with the thread 272 of the body 256. The elastic ring 360 is then introduced into the groove annular 366 of the rod 134 so that the member 358 is locked in place.

 The rod retaining structure 136 which is as shown in FIGS. 10A and 10B, can thus be fixed to the body 256 while the annular member 358 is tightened by hand. The rod 134 can rotate around its axis while a tight seal is formed between the body 256 and the rod 134. The seal formed between the body 256 and the rod 134 also exerts friction forces which allow the orientation of the end inclined and its maintenance in the position chosen by the operator.

 The floating end 370 is fixed to the end of the rod 134 by a retaining structure 372 shown clearly in FIG. 11. This end 370 and the retaining device 372, shown in FIGS. 11 and 12, are similar to the floating end 76 and to the retaining device 100 shown in FIG. 4 and they are therefore not described again in detail. It should however be noted, with reference to FIG. 11, that the passage 144 starting from the rod 134, communicates with the region delimited behind the annular flange 374 on the tip 370.

 Thus, during the operation of the pneumatic separator 120 shown in Figures 7 to 12 and in Figures 15 to 17 as described above, the pressure of the fluid which tends to push the floating tip to the right in Figure 11 is determined or can be determined not only by the pressure in the passage 142 formed in the rod 134, that is to say the pressure adjusted by the valve 294, but also by the pressure prevailing in the passage 144, under the control of the valve 296.

 The pressure prevailing in the passage 142 is that of the fluid which comes from the chamber 186. The pressure in the passage 144 varies however according to the plug 194 or 282 which is in place and the fluid which is transmitted to the outlet structure 158. Thus, when the two plugs 194 and 282 are in place, no fluid is present in the passage 144. Consequently, only the calibrated orifice 378 is used and the cleaning effect is ensured by the gas or the liquid s escaping through the passage 375 as described with reference to the floating end 76 of FIG. 4.

 When only the plug 282 is in place, the pressure in the passage 144 is that of the chamber 186.

When only the plug 194 is in place, the pressure in the passage 144 is that of the outlet structure 158.

 In all cases, depending on the pressure of the fluid acting on the floating tip 370, there is a pressure which tends to move this tip 370 to the right in FIG. 11, as described above. The force available for the separation of the tissues by the rounded end 376 of the tip 370 is then the residual force necessary to move the tip 370 to the left in FIG. 11, despite the forces due to the pressure of the fluid acting on the tip 370 and from passages 142 and 144.

 A thin brush of fluid again circulates in the passage 378 and in the tip 370 and strikes the tissue which thus undergoes a forced separation just in front of the tip 376, as indicated above. In addition, pressurized fluid acts around the outside of the tip 370 and clears the area surrounding the tissue being separated, when one of the plugs 194 and 282 is removed and when the passage 144 is under pressure.

 In such an operation, it should be noted that the surgeon can perfectly adjust the fluid pressures in the passages 142 and 144 given the incorporation of the valves 294 and 296 into the pneumatic separator 120. In this respect, this separator 120 is much more elaborate that the pneumatic separator 52 of FIG. 3, when the surgical operation considered requires it.

 In the variant of pneumatic separator 380 shown in FIGS. 18A and 18B, the valve assembly 382 is modified by replacing the plug 282 of the separator 120 with a plug 384 having an axial passage 386 disposed in the tapped axial cavity 388 formed in the body 390 of the valve assembly.

 In addition, the valve assembly 382 comprises a suction pipe 392 placed in the axial passage 394 and held inside by the threaded end 396 placed in the cavity 388. A check valve 398 is pushed back into the position of closing the passage 386 formed in the plug 384 by the return spring 400, as clearly indicated in FIGS. 18A and 18B, so that the pressurized fluid of the passage 412 cannot go back upstream.

 In such a structure, a source of humidifying fluid such as water is connected by an umbilical cord 402 to the outlet structure 404 so that water is present in the passage 406 of the subassembly 408 of distribution.

 In the variant of separator 380 of FIGS. 18A and 18B, for a suitable difference between the pressure exerted by the spring on the valve 398 and the pressure exerted by the water in the passage 406, the valve 398 opens when it there is sufficient vacuum at the end of the suction pipe 392 because of the venturi effect due to the fluid coming from the passage 410, circulating therein and in the passage 412.

 The moisture coming from the suction pipe 392 is thus mixed with the fluid such as nitrogen gas from passage 412 and is transmitted around the floating end 370. Thus, in the variant of separator 380 of FIGS. 18A and 18B, the fabrics separated can be humidified by separate control of the valve 296 using the thumb, this control being separated from the control of the other valve 294 using the index finger.

 FIGS. 19A and 19B show another variant of pneumatic tissue separator 420 which comprises an outlet connection 422 to an umbilical cord 424 by which blood or other humors coming from the proximity of the separated tissue can be evacuated from the region of separation of fabrics by separator 420.

 Thus, the umbilical cord 424 is directly connected to the passage 426 of the distribution sub-assembly 428, the plug 194 being removed and the passage 434 returning backwards in the form of a passage part 436 so that the fluid such as nitrogen gas or the like flows in passage 430 to the left in Figures 19A and 19B (reverse venturi effect).

 The stream of nitrogen gas flowing in passage 430, to the left in Figures 19A and 19B, creates a vacuum or suction around the tip 438 as shown in Figure 13, so that blood and other tissue debris separated can be drawn into the passage 440 formed in the rod 442 and finally discharged by the umbilical cord 424.

 The ends of the passages 434 and 436 which are connected in the valve assembly 432 are closed by a plug 444, for reasons of simplification of manufacture.

 As clearly shown in Figure 14, the floating tip 438 is modified, as is the internal configuration of the tip retaining device 446. Thus, the annular flange 473 of the end 370 is reduced to flange parts such as the parts 448 shown in FIG. 14 and necessary for guiding the end 438 when it moves in translation in the retaining device 446.

In this way, enlarged zones 450 are formed and allow the suction of debris and separated tissue in the separator 420. These enlarged orifices 450 avoid the use of slots 452 as shown in FIGS. 11 and 12.

 Furthermore, the structure of the pneumatic separators 380 and 420 and the methods used are identical to the structure and the method used in the separator 120.

 It is understood that the invention has been described and shown only as a preferred example and that any technical equivalence may be made in its constituent elements without going beyond its ambit. Thus, the separator can be used as an external ear cleaning device for removing earwax, the nitrogen gas being replaced by a hot oil. In this application, the floating tip is less likely to injure an eardrum or other sensitive parts of the outer ear than the usual cotton swabs and the like used for cleaning the ear canals.

 In addition, the device according to the invention can be used as an accessory to other surgical devices, in various different applications such as endoscopy, bronchoscopy, proctoscopy or sigmoidoscopy. Obviously, many operations may require lengthening the rod and an observation or lighting structure may have to be incorporated in certain applications.

Claims (16)

1. Tissue separator, characterized in that it comprises a handle (12), a rod (14) having a longitudinal axis and fixed to the handle, and a tip (18) held in a fixed position relative to a first end of the rod and having a tissue separation device (40) at a first end. 2. Separator according to claim 1, characterized in that the handle (52), the rod (62) and the end (64) are hollow and allow the circulation of a fluid, and a device (58) is intended to transmit a fluid in the hollow handle. 3. Separator according to claim 2, characterized in that the end (76) is not fixed relative to the rod (82) but is a floating end which can move axially relative to the rod depending on the pressure fluid acting in a balanced manner on structures specially formed on the tip. 4. Separator according to claim 3, characterized in that the floating end (76) is fixed to the rod by a retaining device (100) which has a generally cylindrical shape and which comprises radial slots (110) spaced angularly at its internal face, the rod (82) has a cavity (88) at a first end to which the end retaining device (100) is fixed, and the floating end (76) comprises a generally cylindrical member carrying the device ( 18) of tissue separation at its first end, a radial annular flange (94) placed in the center, a cavity (92) disposed axially at the other end, and an orifice (96) opening radially on the side of the annular flange which is turned towards the first end, through the end and communicating with the cavity formed at the other end of the end so that, when the other end of the end is placed in the cavity of the first end of the rod, the end floats in the retainer. 5. Separator according to claim 3, characterized in that the fluid is water and in that it further comprises a device intended to connect the device which sends the fluid to the hollow handle (52) to a reserve d pressurized water. 6. Pneumatic tissue separator, characterized in that it comprises a body having a rear pressure regulator sub-assembly (126) and a sub-assembly (128) before dispensing, a valve assembly (130) connected to the sub -distribution assembly and intended to ensure the circulation of the fluid at a regulated pressure, in a metered manner, in the distribution sub-assembly, a rod (134), a device (136) for retaining rod on the valve assembly, a floating tip (138) and a tip retaining device (140) for fixing the latter on the rod, and a device for connecting the separator to a reserve of pressurized fluid. 7. Separator according to claim 6, characterized in that the sub-assembly (128) of distribution comprises an internal cylinder having at least one passage (282) formed axially and at least one longitudinal channel formed on its external surface, and a cylinder external hollow fitted on the internal cylinder. 8. Separator according to claim 6, characterized in that the valve assembly has longitudinal passages (284, 286), and a valve disposed transversely in the valve assembly and intersecting at least one of the passages so that it regulates the flow of fluid in the valve assembly (130). 9. Separator according to claim 8, characterized in that the valve assembly (130) is cylindrical and has a central longitudinal passage (280) one end of which can be closed, and a second longitudinal passage (284) formed in the valve assembly, a first end of this passage terminating at a first end in the first longitudinal passage through the valve assembly, and a valve (294) disposed in the second passage for adjusting the flow of fluid in the valve assembly. 10. Separator according to claim 9, characterized in that it further comprises a third longitudinal passage (286) formed in the valve assembly and having a valve (296) intended to regulate the flow of fluid in the assembly to valves (130). 11. Separator according to claim 9, characterized in that it further comprises an elongated tubing (392) for moisture suction placed in the first elongated passage, and a check valve (398) retaining placed in the tube suction so that moisture is sucked into the central passage through the valve when a predetermined vacuum is present in the elongated passage. 12. Separator according to claim 6, characterized in that the rod (442) is an elongated member having two longitudinal passages, one of which communicates axially with a passage (430) formed in the valve assembly and the other communicates with a chamfered surface of the end of the rod, so that it receives fluid from the valve assembly (432), the fluid flowing annularly around the chamfered surface so that the rod can be mounted in any position angular with respect to the valve assembly. 13. Separator according to claim 6, characterized in that the rod (134) has a radial flange (362) around a first end and an annular groove (166) adjacent to the flange and placed between the flange and the other end of the rod, and the rod retainer (138) is an annular member (358) having an annular flange facing inwards and intended to slide on the rod so that the annular flange of the annular member is in cooperation with the # annular flange of the rod, and an elastic ring (364) placed in the annular groove (366) of the rod and fixing the annular member in position on the rod so that it cannot move axially with respect to the latter while allowing relative rotation of the annular member and the rod. 14. Separator according to claim 13, characterized in that it further comprises a sealing ring (276) placed between valve assembly and the rod retaining device, this ring having a dimension such that it exerts forces of friction opposing the relative movement in translation. 15. Lost rod for pneumatic tissue separator, characterized in that it comprises an elongated rod (14), a rod retaining member (32), intended to fix the latter on a pneumatic tissue separator, and a tip (18) placed on the rod and intended to separate fabrics.  16. An assembly comprising an end and an end retaining device intended for a pneumatic tissue separator, said assembly being characterized in that it comprises a hollow cylindrical retaining device (100) having a tapped internal end (102) and a annular radial part at its external end, a floating end (76) having a cavity (92) at its internal end, a central flange (94) for guiding and an external end (78) intended to separate the tissues, and a radial passage (96) formed between the cavity of the internal end and the exterior of the floating end, between the guide flange and the other end of the end.