Ophthalmic surgical system and method for operating ophthalmic surgical system

Abstract

The present invention relates to an ophthalmic surgical system and a method for operating the same, the system comprising: a first fluid pump having a first pump chamber, a first resilient partition element, and a first drive chamber; a second fluid pump having a second pump chamber, a second elastic partition element, and a second drive chamber; a lavage fluid line and a suction fluid line; a first drive fluid line for guiding a first drive fluid to the first drive chamber; a second drive fluid line for guiding a second drive fluid to the second drive chamber; a first position sensor for detecting a first deflection position of the first elastic partition element; a second position sensor for detecting a second deflected position of the second elastic partition element; a first pressure sensor for detecting a first pressure in the first drive fluid line; a second pressure sensor for detecting a second pressure at the outlet of the first pump chamber; and / or a third pressure sensor for detecting a third pressure at the inlet of the second pump chamber; a fourth pressure sensor for detecting a fourth pressure in the second driving fluid line; a direct connection line configured to connect the irrigation fluid line to the suction fluid line; and a processing unit configured to process the first pressure, the second pressure and / or the third pressure, the fourth pressure in each case in a manner dependent on the first deflection position and the second deflection position.

Description

[0001] The present invention relates to an ophthalmic surgical system and a method for operating the ophthalmic surgical system.

[0002] There are many surgical techniques for treating lens opacities (medically known as cataracts). The most widely used technique is phacoemulsification, in which a thin hollow needle is introduced into the lens and induces ultrasonic vibrations. Around it, the vibrating hollow needle emulsifies the lens so that the lens particles produced can be sucked out through a line with the help of a pump. In this process, an irrigation fluid is delivered, and the lens particles and fluid are sucked out through a suction fluid line. When the lens has been completely emulsified and removed, a new intraocular lens can be inserted into the empty capsular bag, so that the patient treated in this way can regain good vision.

[0003] A fluid pump (such as the fluid pump in the ophthalmic surgery system according to DE 10 2016 201 297 B3) can be used to crush the lens with the irrigation fluid of the desired amount at the desired pressure, and to aspirate the suction fluid of the desired amount under the desired pressure. In this process, a plurality of fluid pumps are used. Due to the presence of a plurality of fluid pumps that interact with each other, and the fact that a fluid pump can never be manufactured identically to another fluid pump in principle, the fluid pump may not deliver the fluid to be delivered with the desired accuracy. Even if there is a smaller accuracy deviation in the components used in the fluid pump, it may still lead to an undesirable deviation relative to the fluid to be delivered, so that surgical treatment may be difficult.

[0004] DE 10 2021 111 178 A1 relates to a method for operating a fluid pump and an ophthalmic surgical system having a fluid pump.

[0005] The problem addressed by the present invention is to develop an ophthalmic surgical system with which the supplied irrigation fluid and the removed aspiration fluid can be controlled effortlessly and with high accuracy. Another problem addressed is to develop a method for controlling such an ophthalmic surgical system that can be performed effortlessly.

[0006] This problem is solved by the subject matter of the independent claims. Advantageous developments of the invention are the subject matter of the dependent claims.

[0007] The ophthalmic surgical system includes:

[0008] a first fluid pump comprising a first pump chamber having a first volume and a first drive chamber separated from the first pump chamber by a first elastic separating element and having a second volume,

[0009] a second fluid pump comprising a second pump chamber having a third volume and a second drive chamber separated from the second pump chamber by a second elastic partition element and having a fourth volume,

[0010] an irrigation fluid line for conducting irrigation fluid to the inlet of the first pump chamber, through the pump chamber to the outlet of the first pump chamber, and from the outlet to a first connector configured to be coupled to a surgical instrument,

[0011] an aspiration fluid line for guiding aspiration fluid from a second connector configured to be coupled to the surgical instrument to the inlet of the second pump chamber, through the second pump chamber to the outlet of the second pump chamber,

[0012] a first drive fluid line for conducting a first drive fluid to the first drive chamber, whereby the second volume can be increased by means of a deformation of the first elastic partition element and the first volume can be reduced at the same time,

[0013] a second drive fluid line for conducting a second drive fluid to the second drive chamber, whereby the fourth volume can be reduced by means of deformation of the second elastic partition element and the third volume can be simultaneously increased,

[0014] a first position sensor for detecting a first deflected position of the first elastic separating element,

[0015] a second position sensor for detecting a second deflected position of the second elastic partitioning element,

[0016] a first pressure sensor for detecting a first pressure in the first drive fluid line,

[0017] a second pressure sensor for detecting a second pressure at the outlet of the first pump chamber, and / or a third pressure sensor for detecting a third pressure at the inlet of the second pump chamber,

[0018] a fourth pressure sensor for detecting a fourth pressure in the second drive fluid line,

[0019] a connecting line configured to connect the irrigation fluid line directly to the aspiration fluid line,

[0020] A processing unit is configured to process the first pressure, the second pressure and / or the third pressure, the fourth pressure in each case in a manner that depends on the first deflection position and the second deflection position.

[0021] Acquiring and processing three or four pressure values ​​and using a connecting line that directly connects the irrigation fluid line and the aspiration fluid line to each other allows for accurate and effortless assessment of the actual pressure values ​​set at a first fluid pump located in the irrigation fluid line and a second fluid pump located in the aspiration fluid line. This eliminates the need for the first and second fluid pumps to have nearly identical characteristics, thereby reducing the production requirements for the fluid pumps and components connected thereto. The connecting line makes it possible to obtain accurate information about the fluid conditions in the ophthalmic surgical system without being affected by surgical instruments or the patient's eye.

[0022] Preferably, the system includes a control unit that receives signals from the processing unit and is coupled to a first actuator in the first drive fluid line for controlling the first drive fluid, and to a second actuator in the second drive fluid line for controlling the second drive fluid. The first actuator allows the first drive fluid to be accurately supplied to the first drive chamber. This allows for accurate control of the supply of irrigating fluid from the first pump chamber. This also applies similarly to the second actuator and the second drive fluid line, as well as the second drive chamber and the second pump chamber.

[0023] According to an embodiment, the processing unit is configured to process a difference between the first pressure and the second pressure as a function of the first deflection position.With knowledge of this deflection position-dependent pressure difference, a desired pressure in the irrigation fluid line can be precisely set.

[0024] Preferably, the processing unit is configured to process the difference between the fourth pressure and the third pressure according to the second deflection position.With knowledge of the deflection position-dependent pressure difference, the desired pressure in the suction fluid line can be accurately set.

[0025] Furthermore, the processing unit is preferably configured to process the difference between the second pressure and the third pressure based on the hydraulic resistance in at least a portion of the irrigation fluid line, the connecting line, and at least a portion of the aspiration fluid line. If the absolute value of the pressure difference is divided by the absolute value of the hydraulic resistance in the aforementioned lines, this yields the absolute value of the flow rate through the irrigation fluid line, the connecting line, and the aspiration fluid line. Simultaneously knowing the flow rates in the irrigation fluid line and the aspiration fluid line is advantageous, for example, to determine and replenish the amount of fluid required in the event of an intraocular leak during surgical treatment.

[0026] According to another embodiment, the processing unit is configured to process the flow rate and a time derivative of the first deflection position. The time derivative of the first deflection position corresponds to the speed of movement of the first elastic partition element. Processing the flow rate and the associated speed of the first elastic partition element enables accurate control of the amount of irrigation fluid to be supplied by the first fluid pump and the pressure to be applied during surgical procedures in which sudden and rapid changes in flow or pressure occur in the irrigation fluid line.

[0027] The processing unit may also be configured to process the time derivative of the flow rate and the second deflection position. If the flow rate and the associated velocity of the second elastic separation element are processed, this enables accurate control of the amount of aspiration fluid to be removed by the second fluid pump and the pressure of the aspiration fluid to be applied during surgical procedures in which sudden, rapid changes in flow or pressure occur in the aspiration fluid line.

[0028] According to the present invention, a method for controlling the above-mentioned ophthalmic surgical system comprises the following steps:

[0029] - closing the outlet valve of the first pump chamber and the inlet valve of the second pump chamber,

[0030] - filling the first pump chamber with irrigating fluid,

[0031] - emptying the first drive chamber of the first drive fluid,

[0032] - emptying the second pump chamber of the pumped fluid,

[0033] - filling the second actuating chamber with the second actuating fluid,

[0034] - closing the inlet valve of the first pump chamber and the outlet valve of the second pump chamber,

[0035] - supplying the first drive fluid to the first drive chamber,

[0036] - connecting the irrigation fluid line to the aspiration fluid line by means of the connecting line,

[0037] - opening the outlet valve of the first pump chamber and the inlet valve of the second pump chamber,

[0038] - removing the second drive fluid from the second drive chamber,

[0039] - the first pump chamber is emptied of irrigating fluid and the second pump chamber is filled with irrigating fluid,

[0040] - obtaining measured values ​​of the first deflection position of the first position sensor, the second deflection position of the second position sensor, the first pressure, the second pressure and / or the third pressure, and the fourth pressure,

[0041] - Supplying the measured values ​​to the processing unit.

[0042] Preferably, the value determined by the processing unit is transmitted to a control unit coupled to a first actuator in the first drive fluid line for controlling the first drive fluid and to a second actuator in the second drive fluid line for controlling the second drive fluid.

[0043] Further advantages and features of the present invention are explained with reference to the following drawings, in which:

[0044] Figure 1 A schematic diagram illustrating an embodiment of an ophthalmic surgical system having connectable components is shown;

[0045] Figure 2 A first schematic diagram is shown, which shows the relationship between the signal curve of the first pressure difference and the measurement value from the first position sensor;

[0046] Figure 3 A second schematic diagram is shown, which shows the relationship between the signal curve of the second pressure difference and the measurement value from the second position sensor;

[0047] Figure 4 shows a third schematic diagram showing a signal curve of a third pressure difference in relation to a measurement value from the first position sensor; and

[0048] Figure 5 A fourth schematic diagram is shown which illustrates the signal curve of the third pressure difference in relation to the measured value from the second position sensor.

[0049] Figure 1 A schematic diagram of an embodiment of an ophthalmic surgical system 1 is shown. The system 1 comprises a first fluid pump 2, which comprises a first pump chamber 3 having a first volume and a first drive chamber 5 having a second volume. The first pump chamber 3 and the first drive chamber 5 are separated from each other by a first elastic partition element 4, making it impossible to exchange fluid from the first pump chamber 3 to the first drive chamber 5, or vice versa.

[0050] In the first fluid pump 2, the edge area of ​​the first elastic partition element 4 is permanently attached. If the volume of the first pump chamber 3 is equal to the volume of the first drive chamber 5, the first elastic partition element 4 is in a horizontal position. If the first volume is greater than the second volume, the first elastic partition element 4 is in an expanded position, in which the first elastic partition element can be, for example, substantially convex; Figure 1The first elastic partition element 4 can have any desired geometric shape and can also adopt different positions when there is a volume difference between the first pump chamber 3 and the first drive chamber 5. It is drawn only schematically and not to scale. Figure 1 .

[0051] In its central region, the first elastic partition element 4 may comprise a first element suitable for contactless detection by means of a first position sensor 6. The first position sensor 6 may be an inductive position sensor or a capacitive position sensor. The first position sensor 6 may be arranged at an edge of the fluid pump 2.

[0052] The first drive chamber 5 is connected to a first drive fluid line 7. A first drive fluid 8 can be supplied from a first drive fluid container 9 to the first drive chamber 5 in a manner dependent on a first actuator 10. This process is reversible, so the drive fluid from the first drive chamber 5 can be returned to the first drive fluid container 9 along the drive fluid line 7. The fluid pressure present in the drive fluid line 7 can be detected as a first pressure p1 by means of a first pressure sensor 11, which is preferably coupled to a connector on the drive fluid line 7.

[0053] The first pump chamber 3 can be supplied with irrigation fluid 21 at its inlet 24. The irrigation fluid 21 is contained in an irrigation fluid container 20, which can be connected to the system 1 via a third connector 19 by means of an irrigation fluid line 22. In this case, the irrigation fluid line 22 is connected to the inlet 24 of the first fluid pump 2. The supply of irrigation fluid 21 to the first fluid pump 2 can be enabled or blocked by means of a first inlet valve 23, wherein the first inlet valve 23 belongs to the first pump chamber 3 but does not need to be directly connected to the first pump chamber 3. Filling the first pump chamber 3 with irrigation fluid 21 requires closing a first outlet valve 26 arranged downstream of the first outlet 25, wherein the first outlet valve 26 belongs to the first pump chamber 3 but does not need to be connected to the first pump chamber 3.

[0054] When the first inlet valve 23 is closed and the first outlet valve 26 is open, the irrigation fluid 21 can be forced out of the first pump chamber 8 by the inflow of the first drive fluid 3 into the first drive chamber 5, and can flow to the first outlet 25 and out into the irrigation fluid line 22 to the first connector 27. Immediately downstream of the first outlet 25 of the first fluid pump 2, the ophthalmic surgical system 1 includes a connector for a second pressure sensor 28 on the irrigation fluid line 22, wherein the second pressure sensor 28 can be used to detect a second pressure p2 existing in the irrigation fluid line 22. The first connector 27 is configured to be coupled to a line of a surgical instrument 29, so that in the coupled state, the irrigation fluid can flow to the surgical instrument 29 and can be used for surgical treatment.

[0055] The surgical instrument 29 may include a needle 30 through which an irrigation fluid may flow. The irrigation fluid 21 may be used during phacoemulsification of a lens 32 of an eye 31 .

[0056] If lens particles need to be removed from the eye during phacoemulsification, they can be aspirated through the needle 30 along the aspiration fluid line 41. To this end, the aspiration fluid line 41 is connected to the ophthalmic surgical system 1 via a second connector 40, so that the aspiration fluid can reach the second inlet 44 of the second pump chamber 53 of the second fluid pump 52 after passing through an open second inlet valve 42 arranged in the aspiration fluid line 41. The second inlet valve 42 is an inlet valve belonging to the second pump chamber 53 but does not need to be directly connected to the second pump chamber 53. A third pressure p3 in the aspiration fluid line 41, immediately upstream of the second inlet 44 of the second pump chamber 53, can be detected by means of a third pressure sensor 43, which is immediately upstream of the second inlet 44 and is connected to the connector on the aspiration fluid line 41.

[0057] The second fluid pump 52 is constructed in a manner similar to the first fluid pump 2. The second fluid pump 52 includes a second pump chamber 53 and a second drive chamber 55 arranged adjacent to the second pump chamber, and these chambers are separated from each other by a second elastic partitioning element 54. The edge area of ​​the second elastic partitioning element 54 is firmly connected to the second fluid chamber 52. The position of the second elastic partitioning element 54 can be detected by means of a second position sensor 56, which is, for example, arranged at the edge of the second pump chamber 52 or in contact with the second pump chamber. The second pump chamber 53 has the third volume, and the second drive chamber 55 has the fourth volume.

[0058] The second drive chamber 55 can be emptied or filled with a second drive fluid 58 from a second drive fluid container 59 along a second drive fluid line 57. The drive fluid flow rate is controlled by means of a second actuator 60. The fourth pressure p4 can be detected by means of a fourth pressure sensor 61, which is coupled to the drive fluid line 57 by means of a connector.

[0059] If on the direction of driving fluid container 59, drive fluid is delivered from the second driving chamber 55, then due to pressure balance, suction fluid can flow into the second pump chamber 53.If the second outlet 45 downstream that is arranged at the second fluid pump 52 and the second outlet valve 46 that is arranged in the suction fluid pipeline 41 closes, then when suction fluid flows into, the 3rd volume of the second pump chamber 53 increases, and the 4th volume of the second driving chamber reduces simultaneously.The second outlet valve belongs to the second pump chamber 53, but does not need to be directly connected to the second pump chamber 53.In this process, the second elastic partition element 54 is deformed.If the second inlet valve 42 closes and the second outlet valve 46 is opened, the suction fluid that is positioned at the second pump chamber 53 can flow into the suction fluid pipeline 41 and then flow into the driving fluid collection container 47 by filling the second driving chamber 55 with drive fluid 58.

[0060] The ophthalmic surgical system 1 further comprises a connecting line 48 configured to connect the irrigation fluid line 22 directly to the aspiration fluid line 41. A first end 481 of the connecting line 48 can be connected to the first connector 27, and a second end 482 of the connecting line 48 can be connected to the second connector 40, wherein in this case the system 1 is configured such that no fluid can flow to the surgical instrument 29. Alternatively, the first end 481 of the connecting line 48 can be arranged between the connector for the first pressure sensor 28 on the irrigation fluid line 22 and the first connector 27, and the second end 482 of the connecting line 48 can be arranged between the second connector 40 and the connector for the third pressure sensor 43 on the aspiration fluid line 41, wherein in this case the system is likewise configured such that no fluid can flow to the surgical instrument 29. Figure 1 . It is also possible that the first end 481 of the connecting line 48 is connected to the irrigation fluid line 22 upstream of the first inlet 24, as seen in the flow direction 90, and the other end 482 of the connecting line 48, which is connected to the aspiration fluid line 41, is arranged downstream of the second outlet 45, as seen in the flow direction 91. In this case, it must be ensured that no fluid flows downstream of the first outlet 25 in the flow direction 90 and that no fluid flows toward the second inlet 44 in the flow direction 91. This can be achieved by closing the first outlet valve 26 and the second inlet valve 42.

[0061] Thus, connecting line 48 is configured to connect irrigation fluid line 22 to aspiration fluid line 41 , wherein system 1 is configured to simultaneously prevent fluid connection with surgical instrument 29 .

[0062] Connecting line 48 acts as a direct connection line or “short circuit line.” Thus, system 1 is configured such that between irrigation fluid line 22 and aspiration fluid line 41 , there are no other direct connections along which fluid can flow, along a “bypass line” or line running parallel thereto.

[0063] During an ophthalmic surgical procedure, the irrigation fluid can again flow as aspiration fluid into and out of the connected surgical instrument 29. In this case, the system 1 is configured so that no fluid can flow through the connecting line 48. The system 1 is configured so that fluid can flow through the connecting line 48 only before or after a surgical procedure, but not during the surgical procedure.

[0064] The irrigation fluid line 22 is understood to be a fluid line through which the fluid from the irrigation fluid container 20 can flow to the third connector 19, from which it flows to the first inlet 24 of the first fluid pump 2, then through the first pump chamber 3, and out of the first outlet 25, through the first outlet valve 26 to the first connector 27. When a surgical instrument 29 is connected, the irrigation fluid line 22 also includes a line to the surgical instrument 29 and to the outlet of the surgical instrument 29.

[0065] The aspiration fluid line should be understood as a fluid line through which fluid from a surgical instrument 29 which may be connected to the second connector 40 can flow to the second connector 40, from the second connector to the second inlet valve 42 and to the second inlet of the second pump chamber 53, through the second pump chamber 53 to the second outlet 45 as far as the second outlet valve 46, and from the second outlet valve to the aspiration fluid collection container 47.

[0066] The surgical system 1 further includes a processing unit 70. The processing unit 70 is configured to receive and process signals from the first pressure sensor 11 via a first signal line 71, and to receive and process signals from the second pressure sensor 28 via a second signal line 72. Furthermore, the processing unit 70 is configured to receive and process signals from the third pressure sensor 43 via a third signal line 73, and to receive and process signals from the fourth pressure sensor 61 via a fourth signal line 74. Furthermore, the processing unit 70 is configured to receive and process signals from the first position sensor 6 via a fifth signal line 75, and to receive and process signals from the second position sensor 56 via a sixth signal line 76. The processing unit 70 is connected to a control unit 80 of the ophthalmic surgical system 1, so that the results of processing the signals from the pressure and position sensors can be used to control the first actuator 10 via a seventh signal line 81 and to control the second actuator 61 via an eighth signal line 82.

[0067] Figure 1 The ophthalmic surgical system 1 is shown in which the irrigation fluid container 20 having irrigation fluid 21 and a portion of the irrigation fluid line 22 are not coupled to the third connector 19. In addition, the aspiration fluid collection container 47 and a portion of the aspiration fluid line 41 are not coupled to the fourth connector 49. The surgical handpiece 29 is not coupled to the first connector 27 and the second connector 40. However, the first end 481 of the connecting line 48 is coupled to the irrigation fluid line 22, and the second end 482 of the connecting line 48 is coupled to the aspiration fluid line 49.

[0068] If a surgical treatment (such as phacoemulsification) is to be performed, the irrigation fluid container 20 containing the irrigation fluid 21 and a portion of the irrigation fluid line 22 are connected to the third connector 19. Similarly, the aspiration fluid collection container 47 and a portion of the aspiration fluid line 41 are connected to the fourth connector 49. Furthermore, the surgical handpiece 29 is connected to the first connector 27 and the second connector 40. In this case, however, the first end 481 of the connecting line 48 is not connected to the irrigation fluid line 22 and / or its second end 482 is not connected to the aspiration fluid line 41.

[0069] The following is with the help of Figures 2 to 5 The processing of the signals from the pressure sensor and the position sensor will be explained. The graphs shown in these figures were determined in a state where the connecting line 48 connects the irrigation fluid line 22 and the aspiration fluid line 41 to each other and no fluid can flow to the surgical instrument 29. The graphs represent calibration curves, which can preferably be recorded before surgical treatment.

[0070] When connecting line 48 connects the irrigation fluid line 22 directly to the aspiration fluid line 41 and no surgical handle is used, no particles of emulsified lens 32 and no other fluid from the patient's eye 31 flow in the aspiration fluid line. Instead, irrigation fluid 21 from the irrigation fluid line 22 flows in the aspiration fluid line 41.

[0071] Figure 2 A first diagram 100 is shown having a first graph 101 under the following conditions:

[0072] - the first inlet valve 23 is closed;

[0073] - the first pump chamber 3 is filled with irrigating fluid 21;

[0074] - the first driving chamber 5 is not filled with any driving fluid 8;

[0075] - the first outlet valve 26 is open;

[0076] - a connecting line 48 connecting the irrigation fluid line 22 to the aspiration fluid line 41;

[0077] - No fluid can flow to the surgical instruments;

[0078] - the second inlet valve 42 is open;

[0079] - the second pump chamber 53 contains no fluid;

[0080] - the second drive chamber 55 is completely filled with the drive fluid 58;

[0081] - the second outlet valve 46 is closed;

[0082] - The first drive fluid 8 can flow from the first drive fluid container 9 into the first drive fluid pipeline 7;

[0083] The drive fluid 58 can flow from the second drive chamber 55 to the second drive fluid container 59 .

[0084] The first elastic partition element 4 and the second elastic partition element 54 are in corresponding positions, for example both the partition elements 4 and 54 are initially convex in shape, e.g. Figure 1 As shown. Figures 2 to 5 Therefore, the corresponding partition elements are symbolically drawn in convex form in the left part of the figure. In the corresponding middle part, they are drawn in a relaxed horizontal position, and in the corresponding right part, they are drawn in a concave position.

[0085] In Figure 100, the difference Δp1 between the first pressure p1 and the second pressure p2 is plotted on the ordinate. The displacement x1 detected by the first position sensor 6 is plotted on the abscissa. The left area 102 in the graph 101 shows a difference less than zero. This can be explained as follows. The first elastic partition element 4 and the second elastic partition element 54 are in a convex position with a very obvious deformation and have a high restoring force in the direction of the relaxed position. Only a relatively small amount of the first drive fluid 8 is required to press the irrigation fluid out of the first pump chamber 3 in the direction of the first outlet valve 26. Therefore, the first pressure p1 is slightly lower than the second pressure p2, so the difference Δp1=p1–p2 is a negative value.

[0086] In the middle region 103 of the graph 101, the elastic separation elements 4 and 54 are in a substantially horizontal position and are only slightly deformed or not deformed at all, and are therefore relatively relaxed. In this case, the first pressure p1 of the first drive fluid 8 is substantially the same as or equal to the second pressure p2 of the irrigation fluid. Therefore, in the middle region 103 of the graph 101, the difference Δp1 is substantially zero or equal to zero.

[0087] These values ​​are positive in the right-hand region 104 of the first graph 101. The first drive fluid 8 must exert a relatively large amount of pressure on the first elastic partition element 4 in order to force it into a relatively pronounced concave deformation position. In this case, the irrigation fluid 21 flows out of the first outlet 25 at a relatively low pressure. Therefore, the difference Δp1 = p1 − p2 is positive.

[0088] The pressure difference Δp1 is multiplied by the projected cross-sectional area of ​​the first pump chamber 3 to obtain the compressive force. Therefore, the force-displacement characteristic curve of the first elastic partition element 4 can be determined by means of the first curve diagram 101. It is meaningful to record the force-displacement characteristic curve of the entire stroke of the elastic partition element 4. This corresponds to the situation where the pump chamber 3 is initially filled with irrigating fluid 21 and is completely emptied at the end of the movement of the partition element 4.

[0089] Figure 3 Shown in the above about Figure 2 Second graph 200 shows second graph 201 under the same conditions as indicated. The vertical axis plots the difference Δp2 between the fourth pressure p4 and the third pressure p3. The displacement x2 detected by the second position sensor 56 is plotted on the horizontal axis. The left-hand area 202 in the second graph 201 shows a difference less than zero. The second elastic partition element 54 is significantly deformed convexly and has a high restoring force in the direction of the relaxed position. Therefore, a relatively low pressure needs to be applied to the second drive fluid pipeline 57. Therefore, the fourth pressure p4 is lower in absolute value than the third pressure p3 of the fluid flowing into the second pump chamber 53 at the second inlet 44. Therefore, Δp2 = p4 – p3 is a negative value; see the left-hand area 202 in the graph 201.

[0090] In the middle region 203 of the second graph 201, the second elastic separation element 54 is in a slightly deformed or completely undeformed position. Therefore, the fourth pressure p4 is almost equal to or equal to the third pressure p3, and the difference Δp2 is almost zero or equal to zero.

[0091] In the right region 204 of the second graph 201, these values ​​are positive. To make the second elastic partition element 54 assume a concave shape, a relatively strong negative pressure must be applied to the second drive fluid line 57. Since the third pressure p3 is also negative, Δp2=p4−p3 is a positive value.

[0092] The compressive force is obtained by multiplying the second pressure difference by the projected cross-sectional area of ​​the second pump chamber 53. Thus, the force-displacement characteristic curve of the second elastic pressure element 54 can be determined.

[0093] The first elastic partition element 4 and the second elastic partition element 54 are two different components. They can be manufactured with high precision, but they are not identical. This also applies similarly to the first drive fluid line 7 and the second drive fluid line 57. Similarly, the first pressure sensor 11 and the fourth pressure sensor 43 are two different components that do not provide the same measurement values. Therefore, it should be expected that in an accurate representation, the first graph 101 and the second graph 201 are not identical.

[0094] Figure 4 A third diagram 300 is shown with a third graph 301. In the diagram 300, the difference Δp3 between the second pressure p2 and the third pressure p3 is plotted on the ordinate, ie Δp3 = p2 - p3. The displacement x1 detected by the first position sensor 6 is plotted on the abscissa.

[0095] The second pressure p2 is the pressure in the irrigation fluid line 22 immediately downstream of the first outlet 25 of the first pump chamber 3, and the third pressure p3 is the pressure in the suction fluid line 41 immediately upstream of the second inlet 44 of the second pump chamber 53. The length of the pipeline between the connector of the second pressure sensor 28 to the first end 481 of the connecting line 48, the connecting line 48 to the second end 482 of the connecting line 48, and the connector from the second end to the third pressure sensor 43 has a hydraulic resistance greater than zero. This causes the third pressure p3 to be slightly lower than the second pressure p2. This applies to the entire stroke of the first elastic separation element 4, so the third graph 302 shows a positive pressure difference Δp3 along the entire path x1. If this pressure difference Δp3 is divided by the hydraulic resistance R, then this corresponds to the fluid flow through the specified section.

[0096] Figure 5 A fourth diagram 400 is shown with a fourth graph 401. In this diagram 400, the difference Δp3 between the second pressure p2 and the third pressure p3 is plotted on the ordinate, i.e., Δp3 = p2 - p3. The displacement x2 detected by the second position sensor 56 is plotted on the abscissa. Figure 4 The only difference is that the pressure difference is shown as a function of the second position sensor 56 instead of the first position sensor 6. If this pressure difference is divided by the hydraulic resistance of the length from the connector of the second pressure sensor 28 to the third position sensor 43, this corresponds to the fluid flow through this length.

[0097] It is possible that the hydraulic resistance R of the length extending from the connector of the second pressure sensor 28 to the first end 481 of the connecting line 48, the connecting line 48 to the second end 482 of the connecting line 48, and from the second end to the connector of the third pressure sensor 43 is known, and the fluid flow rate Q along this length is also known. In this case, the second pressure sensor 28 or the third pressure sensor 43 can be omitted. If the second pressure sensor 28 is present and the second pressure p2 is available, but the third pressure sensor 43 or the third pressure p3 is not known, the third pressure is calculated as p3 = p2 – Q*R. In this case, the third pressure p3 is available as a calculated value rather than a measured value, and this third pressure can be determined by the processing unit 70. In contrast, if the third pressure sensor 43 and the corresponding third pressure p3 are known, but the second pressure sensor 28 is not present or the second pressure p2 is not available, the second pressure is calculated as p2 = p3 + Q*R, where this second pressure can be determined by the processing unit 70.

[0098] Using system 1, the spring characteristic curve of the first elastic separation element 4 and the associated flow rate through the irrigation fluid pipeline 22 can be determined to calibrate the first elastic separation element 4 according to the disposable movement from the filled first pump chamber 3 to the emptied first pump chamber 3. This also applies similarly to the second elastic separation element 54. Since this calibration for the first elastic separation element 4 and the second elastic separation element 54 can be performed simultaneously, four characteristic curves can be determined after only one disposable movement sequence from the filled first pump chamber 3 to the emptied first pump chamber 3 or from the emptied second pump chamber 53 to the filled second pump chamber 53. This means that time is significantly saved compared to conventional calibration procedures, in which each pump chamber must be calibrated separately and in sequence at the time.

[0099] Reference numerals

[0100] 1 Ophthalmic surgical system

[0101] 2 First fluid pump

[0102] 3. First pump room

[0103] 4 First elastic separation element

[0104] 5 First drive room

[0105] 6 First position sensor

[0106] 7 First drive fluid line

[0107] 8 First driving fluid

[0108] 9 First drive fluid container

[0109] 10. First actuator

[0110] 11. First pressure sensor

[0111] 19 Third connector

[0112] 20 Irrigation fluid container

[0113] 21 Irrigation fluid

[0114] 22 Irrigation fluid line

[0115] 23 First inlet valve of the first pump chamber

[0116] 24 First inlet of the first pump chamber

[0117] 25 First outlet of the first pump chamber

[0118] 26 First outlet valve of the first pump chamber

[0119] 27 First Connector

[0120] 28 Second pressure sensor

[0121] 29 surgical instruments

[0122] 30 hollow needle

[0123] 31 Eyes

[0124] 32 Lens

[0125] 40 Second connector

[0126] 41 Suction fluid line

[0127] 42 Second inlet valve of the second pump chamber

[0128] 43 Third pressure sensor

[0129] 44 Second inlet of the second pump chamber

[0130] 45 Second outlet of the second pump chamber

[0131] 46 Second outlet valve of the second pump chamber

[0132] 47 Aspirated fluid collection container

[0133] 48 connecting pipelines

[0134] 481 First end of connecting pipeline

[0135] 482 Connect the second end of the pipeline

[0136] 49 Fourth connector

[0137] 52 Second fluid pump

[0138] 53 Second Pump Room

[0139] 54 second elastic separation element

[0140] 55 Second drive room

[0141] 56 Second position sensor

[0142] 57 Second drive fluid pipeline

[0143] 58 Second driving fluid

[0144] 59 Second driving fluid container

[0145] 60 Second actuator

[0146] 61 Fourth pressure sensor

[0147] 70 processing units

[0148] 71 First signal line

[0149] 72 Second signal line

[0150] 73 Third signal line

[0151] 74 Fourth signal line

[0152] 75 Fifth signal line

[0153] 76 Sixth signal line

[0154] 80 control unit

[0155] 81 Seventh signal line

[0156] 82 Eighth signal line

[0157] 90 Flow direction

[0158] 91 Flow direction

[0159] 100 First Picture

[0160] 101 First Graph

[0161] 102 The left area in the first graph

[0162] 103 The middle area in the first graph

[0163] 104 The right area in the first graph

[0164] 200 Second Picture

[0165] 201 Second Curve Graph

[0166] 202 The left area in the second graph

[0167] 203 The middle area in the second graph

[0168] 204 The right area in the second graph

[0169] 300 Figure 3

[0170] 301 Third Curve

[0171] 400 Fourth Picture

[0172] 401 Fourth Curve

[0173] p1 first pressure

[0174] p2 Second pressure

[0175] p3 Third pressure

[0176] p4 Fourth pressure

[0177] Δp1 first pressure difference

[0178] Δp2 Second pressure difference

[0179] Δp3 third pressure difference

[0180] Q fluid flow rate

[0181] R hydraulic resistance

Claims

1. An ophthalmic surgical system (1), comprising: a first fluid pump (2) comprising a first pump chamber (3) having a first volume and a first drive chamber (5) separated from the first pump chamber by a first elastic separation element (4) and having a second volume, a second fluid pump (52) comprising a second pump chamber (53) having a third volume and a second drive chamber (55) separated from the second pump chamber by a second elastic partition element (54) and having a fourth volume, an irrigation fluid line (22) for conducting irrigation fluid (21) to an inlet (24) of the first pump chamber (3), through the pump chamber (3) to an outlet (25) of the first pump chamber (3), and from the outlet to a first connector (27) configured to be coupled to a surgical instrument (29), - an aspiration fluid line (41) for guiding aspiration fluid from a second connector (40) configured to be coupled to the surgical instrument (29) to an inlet (44) of the second pump chamber (53), through the second pump chamber (53) to an outlet (45) of the second pump chamber (53), a first drive fluid line (7) for conducting a first drive fluid (8) to the first drive chamber (5), thereby being able to increase the second volume and simultaneously reduce the first volume by means of deformation of the first elastic partition element (4), a second drive fluid line (57) for guiding a second drive fluid (58) to the second drive chamber (59), thereby enabling the fourth volume to be reduced and the third volume to be increased simultaneously by means of deformation of the second elastic partition element (54), a first position sensor (6) for detecting a first deflected position (x1) of the first elastic separating element (4), a second position sensor (56) for detecting a second deflected position (x2) of the second elastic partitioning element (54), a first pressure sensor (11) for detecting a first pressure (p1) in the first drive fluid line (7), a second pressure sensor (28) for detecting a second pressure (p2) at the outlet of the first pump chamber (3), and / or a third pressure sensor (43), The third pressure sensor is used to detect a third pressure (p3) at the inlet of the second pump chamber (53), a fourth pressure sensor (61) for detecting a fourth pressure (p4) in the second drive fluid line (57), a connecting line (48) configured to directly connect the irrigation fluid line (22) with the aspiration fluid line (41), - a processing unit (70) configured to process the first pressure (p1), the second pressure (p2) and / or the third pressure (p3), the fourth pressure (p4) according to the first deflection position (x1) and the second deflection position (x2), respectively.

2. The ophthalmic surgical system (1) according to claim 1, comprising a control unit (80) which obtains a signal from the processing unit (70) and is connected to a first actuator (10) in the first drive fluid line (7) for controlling the first drive fluid (8), and is connected to a second actuator (60) in the second drive fluid line (57) for controlling the second drive fluid (58).

3. The ophthalmic surgical system (1) according to claim 1 or 2, wherein: The processing unit (70) is configured to process a difference between a first pressure (p1) and a second pressure (p2) according to the first deflection position.

4. An ophthalmic surgical system (1) according to any one of the preceding claims, wherein The processing unit (70) is configured to process a difference between the fourth pressure (p4) and the third pressure (p3) according to the second deflection position.

5. An ophthalmic surgical system (1) according to any one of the preceding claims, wherein The processing unit (70) is configured to process the difference between the second pressure (p2) and the third pressure (p3) based on the hydraulic resistance of at least a portion of the irrigation fluid line (22), the connecting line (48) and at least a portion of the aspiration fluid line (41).

6. The ophthalmic surgical system (1) according to claim 5, wherein: The processing unit (70) is configured to process the flow rate and the time derivative of the first deflection position (x1) together.

7. The ophthalmic surgical system (1) according to claim 5 or 6, wherein: The processing unit (70) is configured to process the flow rate and the time derivative of the second deflection position (x2).

8. A method for controlling an ophthalmic surgical system (1) according to any one of the preceding claims, comprising the following steps: - closing the outlet valve (26) of the first pump chamber (3) and the inlet valve (42) of the second pump chamber (53), - filling the first pump chamber (3) with lavage fluid (21), - emptying the first driving fluid (8) of the first driving chamber (5), - emptying the second pump chamber (53) of the pumped fluid, - filling the second driving chamber (55) with the second driving fluid (58), - closing the inlet valve (23) of the first pump chamber (3) and the outlet valve (46) of the second pump chamber (53), - supplying the first drive fluid (8) into the first drive chamber (5), - connecting the irrigation fluid line (22) to the aspiration fluid line (41) by means of the connecting line (48), - opening the outlet valve (26) of the first pump chamber (3) and the inlet valve (42) of the second pump chamber (53), - exhausting the second drive fluid (58) from the second drive chamber (55), - emptying the first pump chamber (3) of the irrigating fluid (22) and filling the second pump chamber (53) with the irrigating fluid (22), - obtaining measured values ​​of the first deflection position (x1) of the first position sensor (6), the second deflection position (x2) of the second position sensor (56), the first pressure (p1), the second pressure (p2) and / or the third pressure (p3), the fourth pressure (p4), - Supplying the measured values ​​to the processing unit (70).

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