Ophthalmic pressure control systems, kits and methods

Abstract

The invention relates to an ophthalmic pressure control system comprising: a pressure regulator having an input port and an output port; and an infusion line having a proximal end and a distal end, the proximal end being connected to the output port of the pressure regulator and the distal end being removably connected to the ophthalmic irrigation module. Further, the system includes a control unit that drives the pressure regulator to control infusion fluid pressure at the distal end of the ophthalmic irrigation module. The control unit is arranged for performing a fluid calibration process comprising the step of determining a fluid impedance of the ophthalmic irrigation module. The infusion line is associated with a kit of parts including a first ophthalmic irrigation device and a second ophthalmic irrigation device, or the ophthalmic irrigation module is an ophthalmic irrigation device for surgery.

Description

[0001] This application is a divisional application with application date of September 9, 2019, application number 201910848180.1, and invention name “Ophthalmic pressure control system, complete set of components and method”. Technical Field

[0002] The present invention relates to an ophthalmic pressure control system, comprising:

[0003] A fluid pressure regulator having an input port and an output port; an infusion line having a proximal end and a distal end, the proximal end being connected to the output port of the pressure regulator and the distal end being detachably connected to the ophthalmic irrigation module; and a control unit driving the pressure regulator to control the infusion fluid pressure at the distal end of the ophthalmic irrigation module. Background Art

[0004] In ophthalmic surgery, a small probe is inserted into the eye through an insertion port (e.g., a cannula through the pars plana of the eye) to cut, remove, or otherwise process tissue. Typically, an infusion fluid is used to irrigate the interior of the eye by flowing the fluid into the eye through an ophthalmic irrigation module that penetrates the eye. The irrigation module is fed by an infusion line that is pressurized by a fluid pressure regulator. During the treatment of tissue in the interior of the eye, the amount of fluid that leaves the eye through the insertion port can vary over time, for example depending on the surgical action.

[0005] In prior art systems, the fluid flowing toward the eye can be controlled using a control unit that drives a pressure regulator to control the infusion fluid pressure at the distal end of the ophthalmic irrigation module. The control process can be based on the fluid pressure sensed in the interior of the eye. As an alternative, European patent EP2538900B1 in the name of the same applicant discloses estimating the fluid pressure without using a fluid pressure sensor. Summary of the invention

[0006] An object of the present invention is to provide an ophthalmic pressure control system, wherein the process of controlling the infusion fluid pressure at the distal end of an ophthalmic irrigation module is improved. Furthermore, according to the present invention, the control unit is arranged for performing a fluid calibration process, the fluid calibration process comprising the step of determining the fluid impedance of the ophthalmic irrigation module, wherein the infusion line is associated with a kit of parts, the kit of parts comprising a first ophthalmic irrigation device for surgery, the kit of parts further comprising a second ophthalmic irrigation device for calibration, such that the ophthalmic irrigation module detachably connected to the infusion line is the second ophthalmic irrigation device of the kit of parts, or wherein the ophthalmic irrigation module is the ophthalmic irrigation device for surgery.

[0007] By performing a calibration process, the static and / or dynamic fluid response to the action of the pressure regulator can be evaluated, thereby improving the system to compensate for pressure losses within the eye due to surgical actions in the eye, for example, in terms of compensation speed and accuracy, for example, for setting the fluid pressure in the eye to a predefined set point.

[0008] According to one aspect of the present invention, it is proposed that, due to the relatively small size of the irrigation module, the fluid impedance of the ophthalmic irrigation module can have a significant contribution to the fluid behavior of the ophthalmic pressure control system. By determining the fluid impedance of the ophthalmic irrigation module, the overall fluid response of the system can be more accurately estimated, thereby further improving the pressure control process.

[0009] By using the system according to the invention, the intraocular pressure can be kept stable at the value set by the surgeon, regardless of any surgical procedure.

[0010] In addition, the kit includes a first ophthalmic irrigation device for surgery, and the kit also includes a second ophthalmic irrigation device for calibration, so that the ophthalmic irrigation module that is detachably connected to the infusion line is the second ophthalmic irrigation device of the kit, and by associating the infusion line with the kit, the control unit can perform a fluid calibration process without being physically connected to the first irrigation device actually used during the operation, the fluid calibration process including the step of determining the fluid impedance of the irrigation module. Then, the calibration process can be performed while the first irrigation device for surgery is located elsewhere, for example, at the surgical site, for example, penetrated into the eye. After the calibration process is completed, the second irrigation device for calibration can be replaced by the irrigation device for surgery, while the irrigation device for surgery is still at the surgical site, thereby minimizing surgical actions.

[0011] Advantageously, the determined fluid impedance can be compared with a plurality of predetermined fluid impedance calibration reference values ​​associated with the corresponding type of ophthalmic irrigation device. Since in practice the ophthalmic irrigation devices used during calibration belong to a group comprising a limited number of device types, the fluid impedance determination can be used to identify the type of device (i.e., the first device) to be used during the surgical procedure, for example, depending on the geometry and / or size of the device. The fluid impedance calibration reference values ​​can be measured in advance during laboratory conditions and / or using dedicated measurement sensors, and can be provided together with the first device and the second device, for example, in digital form with the documentation of the device. Then, the identification of the device at hand can be obtained without a very precise determination of the fluid impedance. In principle, even a relatively rough, inaccurate determination of the fluid impedance of the second device can be used to identify the type of the first device, especially if the comparison with a plurality of predetermined fluid impedance calibration reference values ​​can be performed with a positive result under a high probability mechanism. If the fluid impedance value determined during the calibration process matches a specific reference value of a plurality of predetermined fluid impedance calibration reference values ​​within a selected probability interval, a positive identification can be made with the type of ophthalmic irrigation device associated with said reference value. Then, upon identifying the type of the first device, the known fluid impedance information of the identified first device may be advantageously used to evaluate static and / or dynamic fluid responses to actuation of the pressure regulator, even when a relatively comprehensive or coarse determination of the fluid impedance is performed during the calibration process.

[0012] The predetermined fluid impedance calibration reference value can be matched to the fluid impedance of the first ophthalmic irrigation device of the corresponding type.The first ophthalmic irrigation device and the second ophthalmic irrigation device of the kit then have the same fluid impedance, and the matched predetermined fluid impedance calibration reference value can be used to evaluate the fluid response.

[0013] Optionally, the predetermined fluid impedance calibration reference value is different from the fluid impedance of the first ophthalmic irrigation device of the corresponding type, but is related to the fluid impedance in a specific way. Then, the first ophthalmic irrigation device and the second ophthalmic irrigation device of the set of parts have fluid impedances that are different from each other, but are related to each other in a specific way. The device type can be determined by determining the fluid impedance of the second ophthalmic irrigation device and associating the determined fluid impedance value of the second device with the corresponding type of the first ophthalmic irrigation device. The step of associating the determined fluid impedance value with the type of the corresponding first ophthalmic irrigation device can be applied by using information about the relationship between the predetermined fluid impedance calibration reference value on the one hand and the fluid impedance of the first ophthalmic irrigation device of the corresponding type on the other hand. The information can be obtained in any way, for example, as a table.

[0014] By associating predetermined fluid impedance calibration reference values ​​with different fluid impedance values ​​of the corresponding first device in a specific manner, the fluid impedances of the first device and the second device in the kit differ from each other in a specific known manner. The fluid impedance of the second device used for calibration can then be set to an impedance regime that can be measured quickly, thereby saving calibration time. As an example, the second device of the kit can have a fluid impedance that is significantly lower than the fluid impedance of the first device.

[0015] The first ophthalmic irrigation device may include an actuator mechanism, such as an actuator mechanism including a phacoemulsification needle and a cannula, while the second ophthalmic irrigation device is a passive device. However, the first irrigation device may be identical to the second irrigation device, such as both devices including an actuator mechanism or both devices being passive, such as being implemented as an infusion cannula.

[0016] Optionally, the ophthalmic irrigation module detachably connected to the distal end of the infusion line during the calibration process is an ophthalmic irrigation device for surgery. Then, even when the device for surgery is in a position to penetrate the eye, a calibration process including the step of determining the fluid impedance of the ophthalmic irrigation module can be performed to probe the device.

[0017] Also in this embodiment, the determined fluid impedance may be compared to a plurality of known, predetermined fluid impedance calibration reference values ​​associated with corresponding types of ophthalmic irrigation devices, thereby relaxing accuracy requirements on the fluid impedance determination.

[0018] Furthermore, the invention relates to a kit of parts.

[0019] The present invention also relates to a method of controlling the pressure of an infused fluid.

[0020] Furthermore, the present invention relates to a computer program product. The computer program product may include a storage medium storing computer executable instructions. For example, the computer program product may include a set of computer executable instructions stored on a data carrier (e.g., a CD or DVD). A set of computer executable instructions that allow a programmable computer to perform the method defined above may also be downloaded from a remote server (e.g., via the Internet). The computer program product may also include a memory storing computer executable instructions and a processor connected to the memory. The processor is capable of executing the computer executable instructions to perform the corresponding operations.

[0021] It should be noted that the technical features described above or below can be embodied in the system or method independently, that is, isolated from the context in which the feature is described, separated from other features, or combined only with multiple other features described in the context in which the feature is disclosed. Each of these features can also be combined with any other disclosed feature in any combination. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will now be further explained based on a number of exemplary embodiments and the accompanying drawings. In the drawings:

[0023] Figure 1 A schematic diagram showing an ophthalmic pressure control system according to the present invention, and

[0024] Figure 2 A flow chart of a method according to the invention is shown.

[0025] It should be noted that the accompanying drawings only illustrate preferred embodiments according to the present invention. In the accompanying drawings, the same reference numerals represent the same or corresponding components. DETAILED DESCRIPTION

[0026] Figure 1 A schematic diagram of an ophthalmic pressure control system 1 according to the present invention is shown. The system 1 comprises a fluid pressure regulator 2 having an input port 3 and an output port 4. The system 1 is also provided with an infusion line 5 having a proximal end 6 and a distal end 7, the proximal end 6 being connected to the output port 4 of the fluid pressure regulator 2. In the illustrated embodiment, the distal end 7 of the infusion line 5 is detachably connected to an ophthalmic irrigation device 8. The infusion line 5 can be implemented as a so-called high-flow infusion line. In addition, the system 1 comprises a control unit 9 driving the fluid pressure regulator 2 for controlling the pressure of the infusion liquid at the distal end 19 of the ophthalmic irrigation device 8.

[0027] During operation of the system 1, the distal end 19 of the ophthalmic irrigation device 8 penetrates the interior of the patient's eye for flowing an irrigation fluid into said interior of the eye. By flowing irrigation fluid into the eye, any internal pressure loss in the eye due to surgical actions in the eye can be compensated. When the fluid pressure regulator 2 is activated, irrigation fluid pressure is applied at the distal end 19 of the ophthalmic irrigation device 8. During operation of the system, the control unit 9 drives the fluid pressure regulator 2 in order to control the infusion fluid pressure at the distal end 19 of the ophthalmic irrigation device 8.

[0028] For the purpose of regulating the fluid pressure through the infusion line 5 , the fluid pressure regulator 2 may be provided with an infusion bottle which supplies the fluid pressure regulator 2 , the infusion line 5 , via a drip chamber connected to the input port 3 of the fluid pressure regulator 2 .

[0029] The control unit 9 is further arranged for performing a fluid calibration process comprising the step of determining the fluid impedance of the ophthalmic irrigation device 8, such that the control unit can statically and / or dynamically control the infusion fluid pressure at the distal end 19 of the ophthalmic irrigation device 8. By characterizing the fluid impedance of the ophthalmic irrigation device 8, which is provided with an internal channel for flowing the irrigation fluid towards the inside of the eye, the static and / or dynamic response of the ophthalmic irrigation device 8 can be estimated, thereby improving the fluid pressure control at the distal end of the module during eye surgery. When performing an eye pressure compensation process, the desired fluid flow characteristics can be set, for example, taking into account the fluid system behavior of the calibration system in terms of volume and time.

[0030] exist Figure 1 In the first embodiment shown, the ophthalmic irrigation device 8 is a passive device having the same fluid impedance as the corresponding ophthalmic irrigation device 10, which includes an actuator mechanism for surgical activities. The actuator mechanism may, for example, include a phacoemulsification needle and a cannula. The fluid impedance of the irrigation module may depend on the size and / or geometry of the fluid channel passing through the interior of the irrigation module, such as length, diameter, curve, etc. By using the passive counterpart of the corresponding ophthalmic irrigation device 10, the control unit 9 can perform a fluid calibration process including the step of determining the fluid impedance of the ophthalmic irrigation device 8 without being physically connected to the ophthalmic irrigation device 10 itself. The ophthalmic irrigation device 8 can be used as a simulation module suitable for performing a fluid calibration process.

[0031] In practice, the ophthalmic irrigation device 10 (e.g., a phacoemulsification cannula) can remain in position for penetration into the eye, such as through a cannula present in the conjunctiva / sclera of the eye. The passive counterpart of the active irrigation device can then be removably connected to the infusion line 5 to perform a calibration process, and then the ophthalmic irrigation device 8 can be removed from the infusion line 5, and the ophthalmic irrigation device 10 can then be removably connected to the infusion line 5 for operatively providing an infusion fluid to the interior of the eye in a controllable manner. In other words, the ophthalmic irrigation device 8 removably connected to the infusion line 5 is replaced by a corresponding ophthalmic irrigation device 10 having the same fluid impedance but including an actuator mechanism.

[0032] exist Figure 1, an ophthalmic irrigation device 8 is connected to the distal end 7 of the infusion line 5, while an ophthalmic irrigation device 10 is not connected. The ophthalmic irrigation device 8 and the ophthalmic irrigation device 10 have the same or similar fluid impedance measured from the proximal ends of the ophthalmic irrigation devices 8 and 10, thereby forming a set of related ophthalmic modules or kits 11. The kit 11 includes an ophthalmic irrigation device 10 for surgery, the ophthalmic irrigation device 10 includes an actuator mechanism, and the kit 11 also includes an ophthalmic irrigation device 8 for calibration, the ophthalmic irrigation device 8 being implemented as a passive device having the same fluid impedance as the ophthalmic irrigation device 10. The ophthalmic irrigation device 10 is used for surgery, such as for placement in or on an eye, and the ophthalmic irrigation device 8 used as a simulation module is used to determine the fluid impedance of the ophthalmic irrigation device 10. The ophthalmic irrigation device 8 can be implemented as a disposable tool (e.g., a simulated cannula) that can be pre-assembled on the distal end 7 of the infusion line 5 as a representative tool of the ophthalmic irrigation device 10. During the calibration process, the fluid resistance of the ophthalmic irrigation device 8 can be measured. The ophthalmic irrigation device 8 can then be removed and the infusion line 5 can in principle be used for surgery.

[0033] A kit of parts can be provided for each size of a specific ophthalmic device, for example, for each cannula size. In addition, the first device and the second device of each kit of parts have the same or similar fluid impedance, which means that the tolerance of the internal channel geometry of the pair of devices has certain limits, so that the estimated intraocular pressure has a predetermined limit.

[0034] It should be noted that the ophthalmic irrigation device 10 can also be implemented as a passive device without the need for an actuator, for example, as an infusion cannula inserted into an eye. The ophthalmic irrigation device used during the fluid impedance determination step can then be the same as another ophthalmic irrigation device connected to the distal end of the infusion line after the fluid impedance determination step is completed (i.e., during surgery). In this case, the set of components 11 can include two identical ophthalmic irrigation devices, namely, an ophthalmic irrigation device 10 for performing a surgical act (e.g., for placement in or on an eye), and an ophthalmic irrigation device 8 for determining the fluid impedance of the device. It should be noted that both identical ophthalmic irrigation devices can be passive, i.e., without any actively driven components or actuator mechanisms, or can both be active, i.e., including actively driven components or actuator mechanisms.

[0035] Therefore, the infusion line 5 can be associated with a set of components, the set of components also including an ophthalmic irrigation device 10 for surgery, the set of components also including an ophthalmic irrigation device 8 for calibration, the ophthalmic irrigation device 10 and the ophthalmic irrigation device 8 having the same fluid impedance, so that the ophthalmic irrigation module detachably connected to the infusion line 5 is the ophthalmic irrigation device 8 of the set of components.

[0036] Advantageously, the determined fluid impedance of the ophthalmic irrigation device 8 is compared to a plurality of predetermined fluid impedance calibration reference values ​​reflecting the fluid impedance of the second device and associated with the corresponding type of ophthalmic irrigation device 10. If a predetermined fluid impedance calibration reference value that is identical to the determined fluid impedance of the ophthalmic irrigation device 8 can be found within predefined limits, the type of ophthalmic irrigation device 10 is identified and the predetermined fluid impedance calibration reference value can be used to evaluate the static and / or dynamic fluid response to the actuation of the pressure regulator, even when a relatively comprehensive or rough determination of the fluid impedance is performed during the calibration process.

[0037] Optionally, the predetermined fluid impedance calibration reference value reflecting the fluid impedance of the ophthalmic irrigation device 8 is different from the fluid impedance of the corresponding type of ophthalmic irrigation device 10, but is related to the type of ophthalmic irrigation device 10 in a one-to-one correspondence. In addition, by determining the fluid impedance of the ophthalmic irrigation device 8 and associating the determined fluid impedance value with the corresponding type of the first ophthalmic device using the information of the above-mentioned one-to-one correspondence obtained in some way (e.g., using a table or algorithm), the device type can be determined. As an example, if the first device impedance is relatively high, the fluid impedance value of the ophthalmic irrigation device 8 is at least one level lower than the fluid impedance value of the ophthalmic irrigation device 10, thereby saving calibration time.

[0038] It should be noted that, as another alternative, the determined fluid impedance of the ophthalmic irrigation device 8 is not compared to a predetermined reference value. The determined fluid impedance itself can then be used to assess the static and / or dynamic fluid response to the actuation of the pressure regulator.

[0039] In a second embodiment, the ophthalmic irrigation module detachably connected to the distal end of the infusion line is an ophthalmic irrigation device 10 for surgery, optionally located in a position to penetrate the eye. The ophthalmic irrigation device 10 may include an actuator mechanism. Then, a calibration process including the step of determining the fluid impedance of the ophthalmic irrigation module can be performed with the ophthalmic irrigation device 10 for surgical use, even when the ophthalmic irrigation device 10 is located in a position to penetrate the eye.

[0040] Furthermore, the determined fluid impedance of the ophthalmic irrigation device 10 may be compared to a plurality of predetermined fluid impedance calibration reference values ​​reflecting the fluid impedance of the device for the purpose of identifying the type of device at hand.

[0041] Figure 2A flow chart of a method according to the present invention is shown. The method is used to control the pressure of an infusion fluid at the distal end of an ophthalmic irrigation module. The method 100 includes: providing a fluid pressure regulator having an input port and an output port (step 110); providing an infusion line having a proximal end and a distal end (step 120), the proximal end being connected to the output port of the pressure regulator; removably connecting the distal end of the infusion line to the ophthalmic irrigation module (step 130); providing a control unit (step 140), the control unit driving the fluid pressure regulator to control the infusion fluid pressure at the distal end of the ophthalmic irrigation module; and performing a fluid calibration process (step 150) including the step of determining the fluid impedance of the ophthalmic irrigation module, wherein the infusion line is associated with a set of components, the set of components including a first ophthalmic irrigation device for surgery, the set of components also including a second ophthalmic irrigation device for calibration, the first ophthalmic irrigation device and the second ophthalmic irrigation device having the same fluid impedance, so that the ophthalmic irrigation module removably connected to the infusion line is the second ophthalmic irrigation device of the set of components, or wherein the ophthalmic irrigation module is an ophthalmic irrigation device for surgery.

[0042] The method may further comprise the step of disconnecting the second ophthalmic irrigation device.The second ophthalmic irrigation device may then be replaced by the first ophthalmic irrigation device.

[0043] The steps of performing the fluid calibration process can be performed using a dedicated hardware structure (such as an FPGA and / or ASIC component), including the step of determining the fluid impedance of the ophthalmic irrigation module. In addition, the method can be at least partially performed using a computer program product, which includes instructions for causing a processor of a computer system to perform the above steps. In principle, some steps can be performed on a single processor. However, it should be noted that at least one step can be performed on a separate processor, for example, the step of determining the fluid impedance of the ophthalmic irrigation module.

[0044] The invention is not limited to the embodiments described herein. It should be understood that many variations are possible.

[0045] These and other embodiments will be apparent to those skilled in the art and are considered to fall within the scope of the invention as defined by the appended claims. For the purpose of clarity and concise description, features are described herein as part of the same or separate embodiments. However, it should be understood that the scope of the invention may include embodiments having a combination of all or some of the features described.

Claims

1. An ophthalmic pressure control system, comprising: a fluid pressure regulator having an input port and an output port; an infusion line having a proximal end and a distal end, the proximal end being connected to the output port of the pressure regulator and the distal end being removably connected to the ophthalmic irrigation module; as well as a control unit that drives the pressure regulator to control the infusion fluid pressure at the distal end of the ophthalmic irrigation module, Wherein, the control unit is arranged for performing a fluid calibration procedure comprising the step of determining a fluid impedance of the ophthalmic irrigation module, and wherein the ophthalmic irrigation module is an ophthalmic irrigation device for use in surgery.

2. A method of controlling the pressure of an infusion fluid at a distal end of an ophthalmic irrigation module, comprising the steps of: providing a fluid pressure regulator having an input port and an output port; providing an infusion line having a proximal end and a distal end, the proximal end being connected to an output port of the pressure regulator; removably connecting the distal end of the infusion line to the ophthalmic irrigation module; providing a control unit that drives the fluid pressure regulator to control the infusion fluid pressure at the distal end of the ophthalmic irrigation module, and A fluid calibration procedure is performed including the step of determining a fluid impedance of the ophthalmic irrigation module, wherein the ophthalmic irrigation module is an ophthalmic irrigation device for use in surgery.

3. The method of claim 2, further comprising the step of comparing the determined fluid impedance to a plurality of predetermined fluid impedance calibration reference values ​​associated with corresponding types of ophthalmic irrigation devices.

4. The method according to claim 3, wherein: The predetermined fluid impedance calibration reference value matches the fluid impedance of the corresponding type of ophthalmic irrigation device.

5. The method according to claim 3, wherein: The predetermined fluid impedance calibration reference value is different from the fluid impedance of the corresponding type of first ophthalmic irrigation device, but is related to the fluid impedance of the corresponding type of first ophthalmic irrigation device in a one-to-one correspondence.

6. The method of any one of claims 3-5, further comprising the step of replacing the second ophthalmic irrigation device with the first ophthalmic irrigation device.

7. A computer program product for controlling an infusion fluid pressure at a distal end of an ophthalmic irrigation module, the ophthalmic irrigation module being removably connected to a distal end of an infusion line, the infusion line having a proximal end connected to an output port of a pressure regulator, the computer program product comprising computer readable code for causing a processor to perform the steps of performing a fluid calibration procedure, the fluid calibration procedure comprising the steps of determining a fluid impedance of the ophthalmic irrigation module, wherein: The ophthalmic irrigation module is an ophthalmic irrigation device used for surgery.

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