JP5410957B2 - Surgical cassette with multi-region fluid chamber - Google Patents

Abstract

A surgical cassette having an aspiration chamber with a bubble separating structure. The bubble separating structure facilitates accurate, reliable measurement of the fluid level in the chamber.

Description

  The present invention relates generally to surgical cassettes for use in microsurgical systems, and more particularly to such cassettes for use in ophthalmic microsurgical systems.

  During small incision surgery, particularly during ophthalmic surgery, a small probe is inserted into the surgical site to remove, remove, or otherwise manipulate tissue. During these surgical procedures, fluid is typically injected into the eye and the injected fluid and tissue are aspirated from the surgical site. The type of suction system that was used prior to the present invention was generally characterized as flow control or vacuum control, depending on the type of pump used in the system. Each type of system has certain advantages.

  A vacuum controlled suction system is operated by setting the desired vacuum level that the system seeks to maintain. The flow rate depends on the intraocular pressure, vacuum level, and resistance to flow in the fluid passage. Actual flow rate information is not available. Vacuum controlled suction systems typically use a venturi pump or a diaphragm pump. A vacuum-controlled suction system provides, for example, the advantages of rapid response time during an air / fluid exchange procedure, reduced vacuum level control, and excellent fluid performance during air suction. A disadvantage of such a system is the lack of flow information, which, in conjunction with the lack of occlusion detection, results in a temporary high flow rate during phacoemulsification aspiration or fracture. Vacuum control systems are difficult to operate in flow control mode due to real-time non-invasive flow measurement problems.

  A flow-controlled suction system is operated by setting a desired suction flow rate for system maintenance. Flow controlled suction systems typically use peristaltic pumps, scroll pumps, or vane pumps. A flow-controlled suction system offers the advantages of a stable flow rate under occlusion and an automatically increasing vacuum level. The disadvantage of such a system is a relatively slow response time, an undesirable occlusion breaking reaction when large compliant components are used, and the vacuum cannot be reduced linearly during tip occlusion. Flow control systems are difficult to operate in the vacuum control mode because the time delay in measuring the vacuum can cause instability of the control loop and reduce dynamic performance.

  One currently available ophthalmic surgical system, the Millennium system from the Storz Instrument Company, uses both a vacuum-controlled suction system (using a venturi pump) and a separate flow-controlled suction system (using a scroll pump). Including. The two pumps cannot be used simultaneously, and each pump requires a separate suction tube and cassette.

Another currently available ophthalmic surgical system, Alcon Laboratories Inc. The ACCURUS® system from US includes both a venturi pump and a peristaltic pump operating in series. Venturi pumps draw material from the surgical site into a small collection chamber. Peristaltic pumps pump aspirated liquid from a small collection chamber into a larger collection bag. Peristaltic pumps do not provide suction vacuum to the surgical site. Therefore, this system operates as a vacuum control system.
US patent application Ser. No. 11 / 158,238 US patent application Ser. No. 11 / 158,259

  Despite these conventional systems, there remains a need for improved suction and infusion fluids within ophthalmic surgical systems.

  The present invention relates to a surgical cassette having a suction or injection chamber disposed in the surgical cassette. The chamber includes a lower sensing portion to allow accurate measurement of fluid level changes and an upper reservoir to allow fluid storage during a surgical procedure. The cross-sectional area of the sensing part is smaller than the cross-sectional area of the storage part.

  For a more complete understanding of the present invention, and for further objects and advantages of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawings.

  The preferred embodiments of the present invention and their advantages are best understood by referring to FIGS. 1-3 of the drawings, wherein like numerals are used for like and corresponding parts of the various drawings.

  The microsurgical system 10 includes a compressed gas source 12, an isolation 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 transducer 24, a suction chamber 26, a fluid level. Includes sensor 28, pump 30, collection bag port 32, suction port 34, surgical device 36, computer or microprocessor 38, and proportional controller 40. The various components of the system 10 are fluidly coupled via fluid lines 44, 46, 48, 50, 52, 54, 56, 58. Various components of system 10 are electrically coupled via interfaces 60, 62, 64, 66, 68, 70, 72, 74, 76. The valve 14 is preferably an “on / off” solenoid valve. The valves 16 to 20 are preferably proportional solenoid valves. The vacuum generator 22 may be any suitable device for generating a vacuum, but the isolation valve 14 and the vacuum proportional valves 16 and / or 18 are open, and the gas from the compressed gas source 12 is supplied to the vacuum generator 22. It is preferably a vacuum tip or a venturi tip that generates a vacuum when passing through. The pressure transducer 24 may be any suitable device for measuring pressure and vacuum directly or indirectly. The fluid level sensor 28 may be any suitable device for measuring the level of the fluid 42 in the suction chamber 26, but preferably it can continuously measure the fluid level. Most preferably, the fluid level sensor 28 is an optical sensor capable of continuously measuring the fluid level. The pump 30 may be any suitable device for generating a vacuum, but is preferably a peristaltic pump, a scroll pump, or a vane pump. The microprocessor 38 can implement feedback control, and preferably PID control. Proportional controller 40 may be any suitable device for proportionally controlling system 10 and / or surgical device 36, but is preferably a foot control device.

  System 10 preferably utilizes three separate methods of controlling suction: vacuum control, wicking control, and flow control. These methods are described in more detail in US Pat. Nos. 5,099,086 and 5,056,086, both of which are co-owned by this application and incorporated by reference in this application.

  In each of these methods, a vacuum can be provided to the surgical device 36 and the suction chamber 26 via fluid lines 50, 56, 58. The suction chamber 26 is filled with fluid 42 sucked by the surgical device 36. The fluid 42 includes liquid infusion fluid as well as aspirated ocular tissue. The suction chamber 26 includes a storage unit 130 and a sensing unit 132. The storage unit 130 has a larger cross-sectional area than the cross-sectional area of the sensing unit 132. The cross-sectional area of the storage unit 130 is preferably up to 7.5 times larger than the cross-sectional area of the sensing unit 132, and most preferably about 7.5 times larger than the cross-sectional area of the sensing unit 132. The storage unit 130 and the sensing unit 132 are fluidly coupled. Most preferably, the angle between the reservoir 130 and the sensing unit 132 is about 90 degrees. As can be seen in FIG. 2, the suction chamber 26 is oriented so that the reservoir 130 is toward the top of the surgical cassette 100.

  As shown in FIGS. 2 and 3, the surgical cassette 100 has a main body 102 including a suction chamber 26. The cover that is fluidly sealed to the front side of the body 102 is not shown for clarity. The pinch plate that is fluidly sealed to the rear side of the body 102 is not shown for clarity. Port 108 is fluidly coupled to fluid line 50. The inlet 110 fluidly couples the sensing part 132 of the suction chamber 26 and the fluid line 56. As explained above, fluid line 56 is fluidly coupled to surgical device 36 via port 34 and fluid line 58. The inlet 112 fluidly couples the sensing part 132 of the suction chamber 26 and the fluid line 52. The suction chamber 26, ports 32 and 34, fluid lines 52, 54, 56, port 108, inlet 110, and inlet 112 are preferably molded integrally within the body 102.

During operation, a vacuum is supplied to the suction chamber 26. The fluid 42 is guided from the surgical device 36 to the suction chamber 26. The suction chamber 26 has a dual function. One of these functions is to assist in continuous level sensing that can determine flow measurements. Flow measurement can be obtained as follows.
Q = A × ΔL / Δt
Here, Q is a flow rate, A is a sectional area of the sensing unit 132, ΔL is a change in fluid level measured by the fluid level sensor 28, and Δt is a change in time. It is important to make an accurate and precise measurement of the level of the fluid 42 in the suction chamber 26. In order to increase the sensitivity of flow measurement, the cross-sectional area of the suction chamber 26 perpendicular to the fluid level sensor 28 needs to be small. This function is achieved by the sensing part 132 of the suction chamber 26. The fluid 42 enters the sensing part 132 of the suction chamber 26 via the inlet 110. Due to the smaller cross-sectional area of the sensing portion 132, the fluid level sensor 28 can accurately and precisely determine the change in fluid level in the suction chamber 26. Another function of the suction chamber 26 is to retain additional fluid 42 to assist in uninterrupted surgical procedures during replacement of a collection bag (not shown) fluidly coupled to the collection bag port 32. It is. If there is a need to store fluid in the suction chamber 26 during a surgical procedure, as is true during replacement of the collection bag, the reservoir 130 of the suction chamber 26 can provide sufficient volume for fluid storage. Provide a large cross section.

  The present invention is illustrated herein by way of example, and various modifications can be made by those skilled in the art. For example, the present invention may be implemented in the injection chamber 26 of the surgical cassette having both the storage unit 130 and the sensing unit 132 with respect to the suction chamber 26 as described above.

  The operation and structure of the present invention will be apparent from the foregoing description. Although the devices and methods shown or described above have been characterized as preferred, various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims. Can be performed on the apparatus and method.

It is the schematic which showed the suction control of the microsurgical system. It is a front view of the main body of a surgery cassette. FIG. 3 is a rear view of the surgical cassette body of FIG. 2.

Claims (2)

A surgical cassette comprising a suction chamber (26) and a collection bag port (32) ,
The suction chamber (26) includes a fluid level sensing unit (132) and a storage unit (130), and the fluid level sensing unit (132) is disposed near the bottom of the suction chamber (26) . fluidly coupled to the fluid line of the cassette (56) for receiving the aspiration fluid for a surgical, have a first cross-sectional area, the storage unit (130), the top of the suction chamber (26) closely disposed, fluidly coupled to said sensing portion (132), said first have a larger second cross-sectional area than the cross-sectional area, the detection unit (132) for the surgical Aspirate fluid first enters the suction chamber (26 ) from the fluid line (56) through the sensing portion (132) and fills the sensing portion (132) before entering the reservoir (130). , is disposed in front Symbol suction chamber (26) inside,
The collection bag port (32) that is connected via a pump (30) to the sensing portion of the suction chamber (26) (132), the surgical cassette.   The surgical cassette according to claim 1, wherein the second cross-sectional area is 7.5 times greater than the first cross-sectional area.

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