The present invention relates to a medical device, and particularly to a pneumatic circuit for use in the operation of an at least partially pneumatically powered tool. More particularly, the present invention relates to a pneumatic circuit and medical device.
The present disclosure relates to one or more of the following features, elements or combinations thereof. A pneumatic control system is provided for use with a medical device, illustratively a suction biopsy device. The suction biopsy device has a cannula for insertion into a body to a point adjacent to a mass to be examined, and a rotating cutter device is housed within.
A rinse or illustratively saline solution is provided for assisting in the removal of the mass to be examined. A suction is provided for assisting in the removal of the mass to be examined. The control system has an absence of electrical circuitry configured to control the operation of the suction biopsy device. Electrical power is illustratively provided only for the compressor and the vacuum.
A pinch valve is provided. The pinch valve is configured to provide for non-slip line attachment. The pinch valve has a central catch and two opposing catches. A piston is positioned to cooperate with the central catch to reduce the flow of fluid through the line. The piston is controlled pneumatically.
The control system includes a water evaporation assembly. The water evaporation assembly includes a filter, a relief regulator, and a permeable exhaust member. The permeable exhaust member is positioned to point upwardly, dissipating moisture from the control system into the environment. The permeable exhaust member causes the dissipated moisture to evaporate as it is dissipated.
The control system comprises a pressurized gas conduit coupled to a compressor, the conduit having an exit port. A gas-permeable absorber is coupled to the exit port, wherein the absorber is used to collect moisture in the pneumatic circuit and dissipate the moisture into the atmosphere through the absorber. The pressurized gas is used to actuate the medical device.
A vacuum system is configured to create a vacuum in the circuit. The absorber comprises an intake filter not normally configured for use as an absorber, but which absorbs moisture when the pressurized gas is directed through it. A cabinet is provided for housing substantially all of the pneumatic circuit, and the absorber is positioned within the cabinet. Liquid condensed in the pneumatic circuit is illustratively not collected in a liquid reservoir for collecting the condensed liquid.
The biopsy device is composed substantially of polymeric materials and non-magnetic metals and can be used in conjunction with a Magnetic Resonance Imaging device. The absorber comprises a pneumatic filter typically used for filtering intake gases.
A method of removing moisture from a compressed gas system housed in a cabinet is also provided. The method comprises the steps of compressing the gas with a compressor, directing the compressed gas through a conduit to an exit port, directing the compressed gas through the exit port and through a gas-permeable absorber connected to the exit port, and using the absorber to collect moisture from the compressed gas and dissipate the moisture into the atmosphere inside the cabinet.
The absorber is mounted such that it extends from the exit port in a substantially vertically upward direction. The conduit comprises at least one of a heat exchanger, a coalescing filter, and a tube.
In another embodiment, a method of providing compressed gas to a medical device comprises the steps of compressing the gas with a compressor, directing the compressed gas through a conduit to a liquid absorber, directing the compressed gas through the absorber, and using the absorber to collect moisture from the compressed gas and dissipate the collected moisture into the atmosphere.
Additional features of the disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.
FIGS. 36A-B-36 show magnified and full views, respectively, of a circuit diagram of yet another embodiment of a pneumatic circuit; and
One embodiment of the present disclosure is shown in
Biopsy System 2, and particularly hand wand 4, illustratively function in the following manner. A patient having a mass 142 to be removed receives a local anesthetic and the mass is identified and located in the patient. Location methods may include ultrasound, magnetic resonance imaging (MRI), X-Ray, or any other method known in the medical industry. As can be seen in FIGS. 1 and 3A-B, hand wand 4 illustratively includes a hollowed needle or cannula 130 extending there from, the cannula 130 having a sharp distal end 136 for facilitating piercing into the patient's body, and the cannula 130 further having a cutter 134 positioned therein for rotational and axial movement relative to the cannula 130. Cutter 134 is illustratively a cylindrical blade, but other configurations are within the scope of the disclosure. Distal end 136 is illustratively a frusto-conical stainless steel tip press-fitted on the end of cannula 130, the tip having a plastic cutting board (not shown) housed within for receiving cutter 134 when cutter 134 is at its full stroke position.
An aperture 132 is illustratively formed in the cylindrical wall of cannula 130 at its distal end. During operation, as shown in
After cannula 130 is in position in the patient's body, pneumatic circuit 10 directs the retracting and advancing movement of cutter 134 relative to the cannula 130 in response to signals from a foot switch 16, a remote push button 18, or a panel push button 18A (see
Once cutter 134 has completed such a cycle and has returned to the position wherein aperture 132 is closed, pneumatic circuit 10 confirms whether further cutting will be necessary. Such confirmation is received from foot switch 16 or remote push button 18/panel push button 18A, described further herein. In the illustrated embodiment, a short pause of approximately a half second prior to confirmation allows sufficient time for an operator to determine whether additional cutting will be necessary.
If additional cutting is not deemed to be required and the mass 142 is considered removed, the operator removes cannula 130 from the patient's body. If instead confirmation is made that additional cutting is required, pneumatic cylinder 26 causes cutter 134 to again move to the retracted position, thereby opening the aperture 132, and saline is directed through the hand wand 4 and between cannula 130 and cutter 134. Saline passing over the cutting end 140 of cutter 134 is suctioned into the central portion of the cannula 130 with urging from the aforementioned applied vacuum pressure. Suctioning saline through the central portion of cannula 130 serves to flush the cut portion of the mass through the cannula toward a waste canister 28, described further herein. Additionally, the saline serves as a lubricant between the cannula 130 and the cutter 134. In the illustrative embodiment, pneumatic motor 138 is not actuated while cutter 134 is moved toward the retracted position, therefore cutter 134 does not rotate relative to cannula 130 during this retraction phase. Such operation is desirable so that tissue does not wrap around cutter 134 as cutter 134 retracts.
Pneumatic circuit 10 directs the continuous above-described cycling of cutter 134 as long as foot switch 16 or remote push button 18 or panel push button 18A is depressed. Illustratively, ultrasound, magnetic resonance imaging (MRI), or other mass-locating methods known in the art may be used during the procedure in order to monitor the progress of the removal of the mass 142. It is advantageous that Breast Biopsy System 2, in one embodiment, can be used in conjunction with an MRI device because of the majority of its components being pneumatic and non-magnetic.
The components comprising pneumatic circuit 10, and their associated functions in the control of hand wand 4, are described below.
A vacuum pump 19 is shown in
Console 6 is shown in
An alternate embodiment of the evaporation valve assembly 300, as shown in
In the embodiment shown in
The hot exhaust output of the vortex cooling tube could be directed toward absorber 304, where it could function to dissipate the moisture through the absorber as described earlier. Because the water vapor in the absorber would become even more heated by the hot exhaust from the vortex cooling tube, it will evaporate more rapidly.
In the vortex cooling tube embodiment shown in FIGS. 37 and 36A-B35-36, the temperature of the compressed air in filter 310 can be brought below ambient temperature, thereby increasing the amount of moisture removed from the compressed air stream. In some embodiments, this may provide sufficient cooling in the compressed air stream such that a heat exchanger is no longer needed in the system. Removal of a heat exchanger from the system would also minimize the size of the system.
Custom designed manifolds 47, 49 can be seen in perspective view in
Sensor 20 (shown in
A saline supply 152 (
Collection canister 28 collects biological material from the medical device 70 during the medical procedure using vacuum pressure. In addition to the biological material being collected, saline is collected in this manner. If the vacuum pressure fails, such failure is sensed by vacuum switch 30, and the cycle stops. Otherwise, pressurized gas continues to be delivered for a period of time determined by timing circuit 148.
Timing circuit 148 incorporates a restricted orifice that fills volume chamber 144 with gas and eventually signals valve 146 to turn on the pressurized gas to medical device 70. Pressurized gas causes cutter cylinder 26 to advance at a rate controlled by timing circuit 38 until it reaches the extended position (also the position held during insertion of the cannula of the illustrative medical device, described above). Such pressurized gas continues to build up in medical device 70 until pressure sensor 52 senses a predetermined gas pressure in cutter cylinder 26 and illustratively trips at approximately 24 psi, indicating the end of the stroke. At such a point, signaling device 54 causes a momentary audible signal, and also latch relay 24 resets, turning off device 70. If signal 22 is still present, the relay 24 will not reset and the process will automatically repeat. If the process repeats the audible tone has a shorter duration than if it resets.
It is also possible that cutter cylinder 26 does not fully advance to the extended position before pressure sensor 52 trips. In such an instance, cutter cylinder 26 may encounter difficulties cutting through the mass 142, and pressure will build up in cutter cylinder 26 even though the end of the stroke has not been reached. When the cylinder pressure reaches the predetermined amount of 24 psi, sensor 52 trips, regardless of the position of cutter cylinder 26 (and the attached cutter 134).
In another embodiment, an electrical vacuum transducer may be used to monitor the vacuum level in the canister. When the sample is taken and discharged into the collection chamber, the vacuum level will drop. This vacuum drop can be used to indicate that a sample has been successfully taken, and a signal can inform the operator each time a sample has been successfully collected. In such an embodiment, if this pressure drop is not sensed and/or when the tissue is too dense for the cutter to advance, the cutter advance rate and force will be modified proportionally. This may assist with cutting denser tissue. If the tissue is particularly difficult to cut, the system may be instructed to just stall out and not take a sample.
In such an embodiment, an electronic processor can be used to adjust the air motor and cutter pressures and cycle times automatically. The system effectively modifies the pressure and timing settings based on the tissue density.
This adaptive control system will monitor the cutter cylinder back pressure and vacuum level with electronic transducers. The pressure levels will be controlled by the processor via electronic pressure regulators. By monitoring the back pressure versus time, the processor will know if the cutter is moving freely through the tissue or stalling out. Also, by monitoring the vacuum transducer, the processor will know if the specimen was drawn through the inner cannula. With the data from the previous cycle, the processor can increase the cutter pressure and air motor pressures independently and run again. The processor can also be programmed to increase the pressures and/or cycle times of each cycle until the vacuum transducer verifies that a specimen has been taken. The settings can also be programmed to remain the same until the run is complete and can then revert back to the “home” settings for the next medical procedure.
In such an embodiment, both the cutter cylinder and air motor pressure set point can be a function of the pressure, vacuum transducer feedback, and time. In another control scheme, the pressures can be adjusted during the cycle to maximize the effectiveness of the cycle.
In another embodiment, the pressure of the air motor may be controlled via electronic pressure control. By electronically controlling the air motor pressure, higher pressures may be delivered at start-up, assuring that the motor starts to spin. During regular use, the pressure can be reduced to minimize air consumption. This allows use of a smaller compressor in the console and may permit the use of a smaller air motor in the handpiece. Electronic pressure control of the cutter cylinder will also allow the use of a smaller diameter piston in the handpiece. All of these specifications could contribute to the manufacture of a smaller handpiece.
In another control scheme, the processor could also be programmed to short stroke the cutter cylinder to “nibble” at the tissue when the monitored parameters indicate that a sample has not been taken. Such an action could be automatic and increase the efficiency of the device.
A graphical user interface or display (not shown) may be controlled by the processor, by which an operator may be informed of the progress of the procedure. A graphic representation of the cutter opening could be provided on the display to indicate every step of the process in real time. Additionally, the display can be used to allow the operator to choose a specific handpiece configuration and/or medical procedure. Therefore, the control system will store nominal control parameters for the specific handpiece and medical procedure, (i.e. a unique recipe for that combination). Furthermore, a manual screen could be implemented to allow the operator to adjust the parameters individually, within certain limits, to meet a specific need.
To better illustrate the function of the electrical control system, a typical cycle will be described. Referring to FIGS. 36A-B35-36, once the handpiece has been connected to the control console, primed, and inserted in the body, a pneumatic foot pedal 312 (shown in
When this back pressure is at atmospheric pressure, the cutter cylinder is illustratively fully retracted. The air motor valve 326 is energized and the inner cannula begins to rotate. After the air motor is started, the air motor pressure is reduced by proportional regulator 320. With the air motor running, cutter cylinder valve 322 is de-energized, thereby extending the cutter cylinder at a pressure set by proportional regulator 318. The processor can be configured to monitor pressure transducer 324 versus time. When pressure transducer 324 reaches a predetermined extended pressure, air motor valve 326 will be de-energized and the cutter cylinder valve 322 and pinch valve 328 will be energized. During the cycle, the air motor will stop and the cutter cylinder will retract, and the pinch valve will open and allow saline to flow through the inner cannula. The pinch valve 328 is directed to be de-energized when the cutter cylinder is fully retracted. The vacuum transducer 330 will be monitored by the processor and should see a vacuum drop when the sample clears the inner cannula. The processor will compare the vacuum level of vacuum transducer 330 and the pressure level of pressure transducer 324 with respect to time to determine if the cycle was optimal for a good sample. If the foot pedal remains depressed, the processor will calculate a new set of working parameters for the next cycle and repeat the cycle with new set points for the vacuum transducer 330, pressure transducer 324, and proportional regulators 318 and 320. It is contemplated that this process continues until the operator releases the foot pedal.
Setup switch 44 (
Referring to
The compressor runs continuously. If pressure is sensed by the relief regulator of greater than the set point of 70 psi, it will continuously vent the excess pressure. If the system is on and not in cycle, 99% of the compressor flow rate will vent out of the relief regulator. While the system is cycling the medical device, approximately 40% of the system capability will continuously flow through the relief regulator.
The water that is collected in the bottom of the filter bowl is dissipated with water evaporation subassembly 39. Water passes from the filter 41 through the relief regulator 43 and into the base of the permeable exhaust member 45. The exhaust member 45 acts as a wick, drawing the fluid up the media. The flow rate through the exhaust member 45 and the large “wick” surface area cause the liquid water to evaporate into a gas state. The flow rate through the enclosure caused by the heat exchanger fans removes the water vapor from the cabinet, thus eliminating the need to collect water and drain it from the system. Illustratively, a filter “muffler” is used as a permeable exhaust member 45, the muffler being available from Allied Witan Company, of Cleveland, Ohio, as part number F02.
The pneumatic circuit components are mounted to custom aluminum manifolds 47, 49 minimizing the use of fittings and keeping the system compact. The components are “sub-base” style versions of the component allowing for ease of replacement. Each component that needs adjusted is bench tested and set to the specified level using certified fixtures. Diagrammatic representations of the manifolds can be seen in
Console 6 is designed to isolate the noise and heat created by compressor 11 and vacuum pump 19. Design specifications for console 6 can be seen in
As shown in various views in
Pneumatically actuated stopper 88, shown diagrammatically in
The test module 92 for testing Airtrol electric pressure switch 120 (as shown in
Another test procedure for test module 92 is shown in
Yet another test module 92′ for testing various regulators is shown in
Target pressures during testing of regulators 124, 126, 128 varies depending on the regulator. Model R4 is targeted for 30 psi, rising. Model R2 is targeted for 40 psi, rising. Model RI is targeted for 60 psi, rising. Once pressure is dialed in to the appropriate target, the regulator nut is tightened to prevent knob movement and a permanent marker is used to mark the cannula position of the regulator gauge. Finally, a green dot is placed in the center of the gauge face.
Illustrative parts used in the production of the above-described embodiment can be found in
In yet another embodiment, the spring found in the handpiece can be eliminated by using positive pressure to extend and negative (vacuum) pressure to retract the cutter blade.
It is also possible to use a multi-purpose motor (not shown) that can drive both the compressor and the vacuum. Illustratively, the multi-purpose motor would have two output shafts (or an extended output shaft) that can power both a compressor and a vacuum. Such a multi-purpose motor may be acquired from the manufacturer JUNN-AIR, and contributes to reducing system noise and the space requirements, thereby allowing for a more compact console design.
In still another embodiment of the handpiece, two or more pistons (cutter cylinders) may be used in tandem to develop the force required, yet the tandem design allows for smaller handpiece diameters. A check valve may also be used in place of the cutter cylinder spring. See, for example, U.S. patent application Ser. No. 11/530,900, which discloses the use of a check valve in combination with a tandem piston design.
In still another embodiment, the piston or pistons of the cutter cylinder could be replaced with rolling diaphragms. This embodiment can eliminate friction from the piston and smooth the reciprocating action while reducing costs.
In a further embodiment, the slot in the outer cannula can be tapered on at least the distal end. A tapered or similarly shaped slot allows the inner cannula (cutter) to be guided during the cutting process so that it does not impact the distal end of a squared or similarly shaped slot during operation. The slot could also be tapered without an apex, but rather just so long as the inner cannula (cutter) is guided. This design not only acts as a guide for the inner cannula, it creates a shear or scissor action with the outer cannula increasing the cut efficacy.
In addition to a more capable wand surgical instrument, a handwand may be coupled to a six-axis robotic arm, where the robot control system would precision insert the needle into the body. The surgeon could directly control the robot and target the lesion using MR or other scan devices. If the body was immobilized, the surgeon could target the mass and plot a course for the robot to perform the procedure and the process could be automated. Robotic surgical procedures in the MR operating room have been explored by a company named NeuroArm. Further details are available at www.neuroarm.org, incorporated by reference herein. The combination of the MR compatible robot and the MR compatible air driven wand provides the surgeon with a novel precision-guided surgical instrument.
While the disclosure is susceptible to various modifications and alternative forms, specific exemplary embodiments thereof have been shown by way of example in the drawings and have herein been described in detail. It should be understood, however, that there is no intent to limit the disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the appended claims.
A plurality of advantages arises from the various features of the present disclosure. It will be noted that alternative embodiments of various components of the disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations of a pneumatic circuit that incorporate one or more of the features of the present disclosure and fall within the spirit and scope of the disclosure.
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/972,116 filed Sep. 13, 2007.
Number | Date | Country | |
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60972116 | Sep 2007 | US |