RU2434611C2 - Surgical cassette with multi-zone fluid chamber - Google Patents

Abstract

FIELD: medicine. ^ SUBSTANCE: invention relates to medical equipment. Surgical cassette has located in it aspiration chamber. Aspiration chamber contains sensitive and accumulative parts. Sensitive part for measurement of flowing medium level is located closer to the bottom of aspiration chamber, is functionally connected with hydraulic line of cassette for obtaining surgical aspirated flowing medium and has first area of transverse section. Accumulative part is located closer to the top of aspiration chamber and is hydraulically connected with sensitive part, and has the second area of transverse section, which is larger than the first area of transverse section. Accumulative part functionally provided respective storage of surgical aspirated flowing medium during replacement of collection bag. Sensitive part is located inside aspiration chamber in such a way that surgical aspirated flowing medium first gets into aspiration chamber through sensitive part from hydraulic line and in fact fills sensitive part, before it gets into accumulative part. ^ EFFECT: application of claimed invention will make it possible to extend arsenal of aspiration and jet-stream technology in eye surgical systems. ^ 2 cl, 3 dwg

Description

Technical field

The present invention generally relates to a surgical cassette for use with microsurgical systems, and more particularly, to a cassette that is used with ocular microsurgical systems.

Description of the Related Art

In small incision surgery, and especially in eye surgery, small probes are inserted into the operated area for dissection, removal, or other tissue manipulation. Typically, during such surgical procedures, fluid is poured into the eye, and the infusion fluid and tissue are aspirated from the surgical area. Prior to the present invention, the types of suction systems used generally differed either by flow control or by vacuum control, depending on the type of pump used in the system. Each type of system has certain advantages.

Vacuum-controlled suction systems work by setting the desired level of vacuum that the system seeks to maintain. The flow rate depends on the intraocular pressure, the level of vacuum, and the resistance to flow in the fluid path. No actual flow rate information available. Vacuum suction systems typically use a venturi pump or a diaphragm pump. Vacuum suction systems offer the advantage of a short response time, control of a decreasing vacuum level and good jet performance, despite aspirated air, such as during an air / fluid exchange process. The disadvantages of such systems are the lack of flow information, which leads to a temporary increase in flow during phacoemulsification or fragmentation, combined with the absence of clogging detection. It is difficult for vacuum controlled systems to operate in flow control mode due to problems associated with non-invasive real-time flow measurement.

Stream-controlled aspiration systems work by setting the desired speed of the aspiration stream maintained by the system. Typically, flow control aspiration systems use peristaltic, scroll, or vane pumps. Stream suction systems provide an advantage in the form of steady flow rates and automatic increase in the level of vacuum during blockage. The disadvantages of these systems are the relatively large response time, undesirable responses to the removal of blockage when using large elastic components, and the impossibility of a linear decrease in vacuum during blockage of the tip. It is difficult for systems with flow control to operate in a vacuum control mode, since time delays in the measurement of vacuum can cause instability in the control loop, reducing dynamic performance.

One currently available ophthalmic surgical system, Storz Instrument's MILLENIUM system, contains both a vacuum-controlled suction system (using a Venturi pump) and a separate flow-controlled suction system (using a spiral pump). Two pumps cannot be used at the same time, and each pump requires a separate suction tube and cartridge.

Another currently available ophthalmic surgical system, the ACCURUS® system from Alcon Laboratories, Inc., contains both a venturi pump and a peristaltic pump that operate in series. A Venturi pump aspirates material from the surgical area into a small collection chamber. A peristaltic pump pumps the aspirate from a small collection chamber into a larger collection bag. The peristaltic pump does not provide a suction vacuum in the surgical area. Thus, the system functions as a vacuum control system.

Despite these known systems, there is a need for improved aspiration and infusion inkjet techniques in ophthalmic surgical systems.

SUMMARY OF THE INVENTION

The present invention relates to a surgical cassette that has an aspiration or infusion chamber located therein. The camera includes a lower sensitive part for accurate measurements of fluid level changes, and an upper storage part for carrying out storage of fluids during surgical procedures.

According to the invention, the surgical cassette has an aspiration chamber located in it, the suction chamber comprising:

a sensitive part for measuring the level of the fluid, located closer to the bottom of the suction chamber, functionally connected with the hydraulic line of the cartridge for receiving a surgical aspirated fluid and having a first cross-sectional area, while the indicated first cross-sectional area of the sensitive part functionally provides correct and accurate data continuous changes in fluid level during use of said cartridge;

a storage part located closer to the top of the suction chamber and hydraulically connected to the sensing part and having a second cross-sectional area that is larger than the first cross-sectional area, where the storage part functionally provides appropriate storage of the surgical aspirated fluid during replacement of the collection bag hydraulically connected to a suction chamber, and wherein the sensitive part is located inside the suction chamber so that the surgical aspirated fluid medium first got into the suction chamber through the sensitive part of the hydraulic line and substantially fills the sensitive part, before entering into the collection part.

Preferably, the second cross-sectional area is approximately 7.5 times larger than the first cross-sectional area.

Brief Description of the Drawings

For a more complete understanding of the present invention and its additional objectives and advantages, reference is made to the description below in combination with the accompanying drawings, in which:

Figure 1 is a schematic diagram illustrating aspiration control in a microsurgical system;

Figure 2 is a front view of the body of a surgical cassette; and

Figure 3 is a rear view of the case of the surgical cassette of figure 2.

Detailed Description of Preferred Embodiments

Preferred embodiments of the present invention and their advantages are best understood with reference to figures 1-3, where the same numbering will be used for the same and similar parts of different drawings.

The microsurgical system 10 includes a source of gas under pressure 12, a shutoff valve 14, a vacuum proportional valve 16, an optional second vacuum proportional valve 18, a pressure proportional valve 20, a vacuum generator 22, a pressure sensor 24, an aspiration chamber 2 6, a fluid level sensor 28 media, pump 30, opening 32 of the collection bag, suction opening 34, surgical device 36, computer or microprocessor 3 8 and linear control device 40. Various components of the system 10 are hydraulically The ki are connected via hydraulic lines 44, 46, 48, 50, 52, 54, 56, and 58. The various components of system 10 are electrically connected via interfaces 60, 62, 64, 66, 68, 70, 72, 74, and 76. Valve 14 is preferably an on-off valve with electromagnetic control. Valves 16-20 are preferably electromagnetic proportional valves. Vacuum generator 22 may be any suitable device for producing vacuum, but is preferably a vacuum or venturi microcircuit that creates a vacuum when shut-off valve 14 and vacuum proportional valves 16 and / or 18 are open and gas is supplied from a pressurized gas source 12 passes through a vacuum generator 22. The pressure sensor 24 may be any suitable device for direct or indirect measurement of pressure and vacuum. The liquid level sensor 28 may be any suitable device for measuring the level of the fluid 42 inside the suction chamber 26, but preferably capable of measuring the level of the fluid in a continuous manner. The fluid level sensor 28 is most preferably an optical sensor capable of continuously measuring a fluid level. The pump 30 may be any suitable device for producing a vacuum, but is preferably a peristaltic pump, a scroll pump or a vane pump. The microprocessor 38 is capable of feedback control and, preferably, PID control. The proportional controller 40 may be any suitable device for proportionally adjusting the system 10 and / or surgical device 36, but is preferably a foot controller.

System 10 preferably utilizes three separate methods for controlling aspiration, vacuum control, suction control, and flow control. These methods are more fully described in the U.S. pending application. No. 11 / 158,238, filed June 21, 2005 and at the same time pending U.S. application. No. 11 / 158,259, filed June 21, 2005, which are incorporated herein by reference.

In each of these methods, a vacuum can be provided to the surgical device 36 and the suction chamber 26 through hydraulic lines 50, 56 and 58. The suction chamber 26 is filled with fluid 42 aspirated by the surgical device 36. The fluid 42 includes a fluid infusion fluid as well as an aspirated tissue eyes. The suction chamber 26 includes a collecting part 130 and a sensing part 132. The collecting part 130 has a larger cross-sectional area than the sensitive part 132. The cross-sectional area of the collecting part 130 is preferably up to 7.5 times larger than that of the sensitive part 132, and most preferably about 7.5 times that of the sensitive portion 132. The storage portion 130 and the sensitive portion 132 are hydraulically coupled. The angle between the storage part 130 and the sensitive part 132 is most preferably about 90 degrees. As can be seen in figure 2, the suction chamber 26 is oriented so that the accumulation part 130 is located in the upper part of the cassette 100.

As shown in FIGS. 2 and 3, the surgical cassette 100 has a body 102 including an aspiration chamber 26. A cover that is attached to the front side of the body 102 using a fluid seal is not shown for reasons of clarity. A pressure plate that is attached to the rear side of the housing 102 using a fluid seal is not shown for reasons of clarity. The hole 108 is hydraulically connected to the hydraulic line 50. The passage 110 hydraulically connects the sensitive part 132 of the suction chamber 26 and the hydraulic line 56. As discussed above, the hydraulic line 56 is hydraulically connected to the surgical device 36 through the hole 34 and the hydraulic line 58. The passage 112 hydraulically connects the sensitive a portion 132 of the suction chamber 26 and a hydraulic line 52. The suction chamber 26; holes 32 and 34; hydraulic lines 52, 54, and 56; hole 108; the passage 110 and the passage 112 are preferably molded as a unit in the housing 102.

During the operation, the vacuum is delivered to the suction chamber 26. The fluid 42 is sent from the surgical device 36 to the suction chamber 26. The suction chamber 2 6 has dual functionality. One of these functions is to maintain a continuous reading of the level at which flow rate measurements can be determined. The flow measurement can be obtained as follows:

where Q is the flow rate, A is the cross sectional area of the sensitive portion 132, ΔL is the change in the level of the fluid measured by the fluid level sensor 28, and Δt is the change in time. It is important to have a correct and accurate measurement of the level of the fluid 42 in the aspiration chamber 26. To increase the sensitivity of the flow measurement, the cross-sectional area of the aspiration chamber 26, perpendicular to the fluid level sensor 28, is small. This function is performed by the sensitive part 132 of the suction chamber 26. The fluid 42 enters the sensitive part 132 of the suction chamber 26 through the passage 110. The smaller cross-sectional area of the sensitive part 132 allows the fluid level sensor 28 to correctly and accurately detect changes in the level of the fluid inside the suction chamber 26 Another function of the suction chamber 26 is to hold the additional fluid 42 to ensure the continuity of the surgical procedure during the change of the collection bag (not showing ) Hydraulically connected with the opening 32 of the collecting pouch. If during the surgical procedure it becomes necessary to store the fluid in the suction chamber 26, as is the case with the replacement of the collection bag, the collection portion 130 of the suction chamber 2 6 provides a large cross-section that provides sufficient storage space for the fluid.

Here, the present invention is illustrated by examples, and various modifications can be made by a person skilled in the art. For example, the present invention may be practiced in a suction chamber 26 of a surgical cassette having both a storage part 130 and a sensing part 132, in contrast to the suction chamber 26, as described above in this document.

It is believed that the operation and construction of the present invention will be apparent from the description given. While the device and methods shown or described above have been described as preferred, various changes and modifications to them can be made without deviating from the nature and scope of the invention defined by the following claims.

Claims (2)

1. A surgical cassette having an aspiration chamber disposed therein, the aspiration chamber comprising: a sensing portion for measuring a fluid level, located closer to the bottom of the aspiration chamber, operably coupled to the cassette’s hydraulic line to produce a surgical aspirated fluid and having a first cross-sectional area wherein said first cross-sectional area of the sensitive part functionally provides correct and accurate data on continuous level changes i fluid while using the specified cartridge; a storage part located closer to the top of the suction chamber and hydraulically connected to the sensing part and having a second cross-sectional area that is larger than the first cross-sectional area, where the storage part functionally provides appropriate storage of the surgical aspirated fluid during replacement of the collection bag hydraulically connected to a suction chamber, and wherein the sensitive part is located inside the suction chamber so that the surgical aspirated fluid medium first got into the suction chamber through the sensitive part of the hydraulic line and substantially fills the sensitive part before reaching the collecting part. 2. The surgical cassette according to claim 1, where the second cross-sectional area is approximately 7.5 times larger than the first cross-sectional area.

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