Patent Description:
Many microsurgical procedures require precision cutting and/or removal of various body tissues. For example, certain ophthalmic surgical procedures require the cutting and/or removal of the vitreous humor, a transparent jelly-like material that fills the posterior segment of the eye. The vitreous humor, or vitreous, is composed of numerous microscopic fibrils that are often attached to the retina. Therefore, cutting and removal of the vitreous must be done with great care to avoid traction on the retina, the separation of the retina from the choroid, a retinal tear, or, in the worst case, cutting and removal of the retina itself. Delicate operations such as mobile tissue management (e.g., cutting and removal of vitreous near a detached portion of the retina or a retinal tear), vitreous base dissection, and cutting and removal of membranes are particularly difficult.

The use of microsurgical cutting probes in posterior segment ophthalmic surgery is well known. Such vitrectomy probes are typically inserted via an incision in the sclera near the pars plana. The surgeon may also insert other microsurgical instruments such as a fiber optic illuminator, an infusion cannula, or an aspiration probe during the posterior segment surgery. The surgeon performs the procedure while viewing the eye under a microscope.

Standard vitrectomy probes typically include a hollow needle with a port on the end to pull in vitreous fibrils. An inner member, placed within the hollow needle, moves back and forth to open and close the port. This operates to cut any fibrils that enter the port while it is open. The rate at which the inner member moves with respect to the hollow needle is referred to as the cut rate. In some cases it is desirable to have a high cut rate. But, in some cases, it is desirable to have a relatively low, but more precise, cut rate. In some cases, it may even be desirable to perform a single cut. There is a need for continued improvement in the use and operability of vitrectomy probes. The systems discussed herein are arranged to address one or more of the deficiencies in the prior art. <CIT> discloses a vitrectomy probe with integral valve. <CIT> discloses an apparatus and method for performing ophthalmic procedures. <CIT> discloses a burst mode vitrectomy system. <CIT> discloses a system and method for actuation of a vitreous cutter.

The invention is defined by independent claim <NUM> of the appended set of claims.

This disclosure relates generally to, and encompasses, apparatuses for removing fluid from the eye, and more specifically to ophthalmic surgical systems of using the systems to remove fluid from the eye.

An ophthalmic surgical system for treating an eye of a patient includes a body and a cutting element extending distally from the body. The cutting element includes a sleeve member comprising a port at an end. The cutting element also includes an inner member disposed within the sleeve member, the inner member being movable axially with respect to the sleeve member to open and close the port. The cutting element also includes an actuating element secured to the inner member, the actuating element configured for operation in both a resonant mode and a non- resonant mode. Operation in the resonant mode causes reciprocal movement of the inner member under application of a constant supply of pressurized fluid and operation in the non-resonant mode causes movement of the inner member in accordance with a pulse of pressurized fluid.

An ophthalmic surgical system includes a probe. The probe includes a body and a cutting element extending distally from the body. The cutting element includes a sleeve member comprising a port at an end. The cutting element also includes an inner member disposed within the sleeve member. The cutting element also includes an actuating element configured to move the inner member axially with respect to the sleeve member to open and close the port. The actuating element includes a chamber, a diaphragm that is movable within the chamber, and a flow director cooperatively associated with the inner member such that movement of the inner member causes a delayed switching of the slide valve. The system also includes a console comprising a pressurized fluid source in fluid communication with the probe.

A method of using a vitrectomy probe said method not being part of this invention includes operating in a resonant mode by applying a pressurized fluid that is pressurized above a threshold value to an actuating element of the vitrectomy probe. The actuating element reciprocally actuates an inner member of a cutting element with respect to a sleeve member of the cutting element. The inner member is positioned within the sleeve member. The sleeve member extends distally from a body of a probe. The sleeve member comprises a port positioned such that actuating the inner member opens and closes the port. The method further includes operating in a non-resonant mode by applying a controlled, pressurized fluid below the threshold value to cause at least one single cycle of movement of the inner member with respect to the sleeve member.

The accompanying drawings illustrate embodiments of the devices disclosed herein and together with the description, serve to explain the principles of the present disclosure.

It will nevertheless be understood that no limitation of the scope of the disclosure is intended. Any alterations and further modifications to the described devices, instruments, methods, and any further application of the principles of the present disclosure are fully contemplated as would normally occur to one skilled in the art to which the disclosure relates. For simplicity, in some instances the same reference numbers are used throughout the drawings to refer to the same or like parts.

The present disclosure relates to apparatuses, systems, and methods for removing ocular tissue and/or fluid from the eye. The various figures show embodiments of exemplary ophthalmic surgical probes and methods of using the probes to remove ocular tissue and/or fluid from a patient's eye. Some embodiments described herein incorporate a dual mode vitrectomy probe that can operate in either a high cut-rate resonant mode or a low cut-rate or single cut non-resonant mode. One of ordinary skill in the art, however, would understand that similar embodiments could be used to remove tissue and/or fluid from other locations in the body without departing from the general intent or teachings of the present disclosure.

<FIG> is a diagram showing an illustrative vitrectomy surgical system <NUM>. According to the present example, the vitrectomy surgical system <NUM> includes a base housing <NUM> and an associated display screen <NUM> showing data relating to system operation and performance during a vitrectomy surgical procedure. In this exemplary embodiment, the vitrectomy surgical system <NUM> includes a mobile console <NUM> that may be used by a health care provider to perform a vitrectomy surgical procedure. The vitrectomy surgical system <NUM> includes a dual mode vitrectomy probe <NUM> and is configured to be used during an ophthalmic surgical procedure, such as, for example, a vitrectomy surgical procedure. The base housing <NUM> may be configured to process, receive, and store data and provide signals to the vitrectomy probe and/or the display <NUM>.

<FIG> is a stylized diagram showing a portion of the illustrative dual mode vitrectomy probe <NUM>. <FIG> shows a longitudinal cross-sectional view of the vitrectomy probe <NUM>. According to the present example, the vitrectomy probe <NUM> includes a body <NUM>, which is shown in part. The body <NUM> supports a cutting element <NUM> that includes a sleeve member <NUM>, an inner member <NUM>, and an actuating element <NUM>.

The body <NUM> may be made from a variety of materials commonly used to form such tools. For example, the body <NUM> may be made of a lightweight aluminum, plastic, or other material. The exterior portion of the body <NUM> may be ergonomically designed for comfortable grasping by a surgeon or operator of the vitrectomy probe <NUM>. The inner portion of the body <NUM> is designed to support the cutting element <NUM> and other features that may be included with the probe <NUM>.

The cutting element <NUM> includes the inner member <NUM> and the sleeve member <NUM>. The sleeve member <NUM> is a hollow needle designed to enter a patient's eye. The sleeve member <NUM> includes a port <NUM> at the distal end. The port <NUM> is disposed along the side of the distal end as illustrated. The port <NUM> may be a square, rectangular, circular, elliptical, or other shaped opening. The opening is designed to allow vitreous fibrils from the patient's eye to enter. Movement of the inner member <NUM> within the sleeve member <NUM> operates to open and close the port <NUM>, thereby cutting any vitreous fibrils that enter the port <NUM> while it is open.

The inner member <NUM> of the cutting element <NUM> is a hollow tube that operates as the cutter portion of the vitrectomy probe <NUM>. Thus, the distal end of the inner member <NUM> is sufficiently sharp to cut vitreous fibrils. The inner member <NUM> may be made from a variety of materials, including for example, stainless steel and others. In some cases, the inner member <NUM> may include multiple members attached together. For example, the distal end of the inner member <NUM> may be a cutter member made of a different material than the proximal end. The proximal end of the inner member <NUM> may be connected to an actuating element <NUM> that moves the inner member <NUM> with respect to the sleeve member <NUM>.

The actuating element <NUM> is designed to move the inner member <NUM> with respect to sleeve member <NUM> in one of a plurality of modes. Specifically, the actuating element <NUM> may operate in a resonant mode. In the resonant mode, a constant pressurized fluid is supplied to the probe <NUM>. The actuating element <NUM> then moves at a very high rate under application of such pressurized fluid. The actuating element <NUM> may also operate in a non-resonant mode. In the non-resonant mode, controlled pulses of pressurized fluid are supplied to the probe <NUM>. In some examples, a single pulse causes a single cut. In some examples, a series of pulses is used to operate the probe <NUM> at a low cut-rate.

<FIG> and <FIG> are diagrams showing an illustrative dual mode vitrectomy probe <NUM> in a resonant mode. According to the present example, the probe <NUM> includes an actuating element <NUM> that includes a spring loaded diaphragm <NUM> within a chamber <NUM>. The chamber <NUM> is in fluid connection with a flow director such as a slide valve <NUM>. The slide valve <NUM> is in fluid communication with two switch valves <NUM>, <NUM>. The configuration of the switch valves <NUM>, <NUM> can be used to determine how pressurized fluid is applied to the probe, and thus, the mode in which the probe <NUM> operates.

In one example, the chamber <NUM> is a cylindrical chamber having holes at each end through which the inner member <NUM> can pass. The chamber <NUM> may be secured to the internal body of the probe <NUM>, thereby fixing the chamber <NUM> in place. The chamber <NUM> is not secured to the inner member <NUM>, and thus the inner member <NUM> can move with respect to the chamber <NUM>. The chamber <NUM> also includes a proximal section <NUM> that can be filled with a fluid. The fluid may also be vented out of the proximal section <NUM>.

The chamber <NUM> includes the diaphragm <NUM> that is movable within the chamber <NUM>. The diaphragm <NUM> is secured to the inner member <NUM> such that movement of the diaphragm <NUM> causes respective movement of the inner member <NUM>. In some embodiments, the diaphragm <NUM> may be disc shaped to fit within the cylindrical chamber <NUM> and form a seal around the circumferential edges of the diaphragm <NUM>. Other shapes for the chamber <NUM> and diaphragm <NUM> are contemplated.

The diaphragm <NUM> is connected to the distal end of the chamber <NUM> through a biasing element <NUM> such as a spring mechanism <NUM>. The biasing element <NUM> places a force on the diaphragm <NUM> in the proximal direction. Thus, pressurized fluid entering the chamber will cause the diaphragm <NUM> to move against the spring force, thus causing the inner member <NUM> to move in a distal direction and close the port <NUM>. When the fluid within the proximal section <NUM> is no longer pressurized, the spring force from the biasing element <NUM> will push the fluid back out of the chamber <NUM>, thus moving the inner member <NUM> in a proximal direction to open the port <NUM>.

Fluid enters the chamber <NUM> through a port <NUM>. The port <NUM> is in fluid communication with a slide valve <NUM>. In this embodiment, the slide valve <NUM> moves between one of two positions. In the first position, as illustrated in <FIG>, path <NUM> is open and path <NUM> is closed. In the second position, which is illustrated in <FIG>, path <NUM> is closed and path <NUM> is open.

The slide valve <NUM> acts as a flow director because it directs the flow of fluid between the chamber <NUM> and the console switch valves <NUM>, <NUM>. Specifically, the flow directing slide valve <NUM> switches to direct the flow into or out of the chamber <NUM>. According to the present example, the slide valve <NUM> includes a slider <NUM> that moves between two positions. The slider <NUM> is secured to the inner member <NUM> such that movement of the inner member <NUM> causes a delayed switching of the slide valve <NUM>. For example, the slider <NUM> of the slide valve <NUM> may be connected to the inner member <NUM> through a spring mechanism <NUM>.

In the present example, the spring mechanism <NUM> is always under compression, and thus pushes the slider <NUM> to an opposite position of the inner member <NUM>. For example, while the inner member <NUM> is in the proximal position, the spring mechanism <NUM> pushes the slider <NUM> into the distal position as illustrated in <FIG>. As the inner member <NUM> moves from the proximal position to the distal position, it will eventually pass a center point at which the spring mechanism <NUM> will then push the slider into the proximal position as illustrated in <FIG>. Thus, the slider <NUM> will tend to be in the opposite position of the inner member <NUM>. As will be described in further detail below, this provides some hysteresis to the system, thus allowing for the resonant nature of the actuating element <NUM>.

The console <NUM> includes a pressurized fluid supply <NUM> that is provided to two console switch valves <NUM>, <NUM>. The console switch valves <NUM>, <NUM> may be in either a supply mode or a vent mode. In supply mode, the pressurized fluid from the fluid supply <NUM> is passed through the switch valves <NUM>, <NUM>. In vent mode, the fluid supply <NUM> is disconnected and any fluid from the probe <NUM> may be vented through the console switch valves <NUM>, <NUM>. Switch valve <NUM> is connected to path <NUM> of the slide valve <NUM> through line <NUM>. Switch valve <NUM> is connected to path <NUM> of the slide valve <NUM> through line <NUM>.

<FIG> illustrates stage <NUM> of the resonant mode. While in resonant mode, console switch valve <NUM> is in vent mode, and console switch valve <NUM> is in supply mode. Additionally, a constant supply of pressurized fluid is provided through the pressurized fluid supply <NUM>. Thus, pressurized fluid passes through console switch valve <NUM>, line <NUM>, path <NUM>, line <NUM>, and into the proximal section <NUM> of the chamber <NUM> through port <NUM>. As the proximal section <NUM> of the chamber <NUM> fills up with pressurized fluid, the diaphragm <NUM> is pushed in a distal direction, thus moving the inner member <NUM> in the distal direction so as to close the port <NUM>. The slider <NUM> of the slide valve <NUM> will remain in the illustrated position for a sufficient amount of time to let the chamber <NUM> fill up with fluid and move the inner member <NUM>. Eventually, the spring force of the spring mechanism <NUM> will push the slider <NUM> of the slide valve <NUM> into the second position.

<FIG> illustrates stage <NUM> of the resonant mode. When the diaphragm <NUM> and inner member <NUM> are in the distal position, the slider <NUM> will have been pushed to the second position. With the slider <NUM> in the second position, the pressurized fluid within the chamber <NUM> is vented out of the port <NUM>, back through line <NUM>, through path <NUM>, through line <NUM>, and vented out of console switch valve <NUM>. As the pressurized fluid is vented out of the chamber <NUM>, a biasing force, such as a spring force from the biasing element <NUM> pushes the diaphragm <NUM> and the inner member <NUM> back into the proximal position. After the chamber is sufficiently vented to allow the inner member to move proximally, the force of spring <NUM> will move the slider <NUM> back to the first position, wherein the cycle starts again as pressurized fluid from the pressurized fluid supply <NUM> is pumped through console switch valve <NUM> and eventually into the chamber <NUM>. The resonant mode may be particularly useful when high cut-rates, such as cut-rates exceeding <NUM>,<NUM> cuts per minute, are desired.

<FIG> is a diagram showing the illustrative dual mode vitrectomy probe in a non-resonant mode. According to the present example, in the non-resonant mode, a single cut or a low cut-rate may be performed as described below. To perform a single cut, both console switch valves are set in supply mode. Then, pressurized fluid is supplied through both console switch valves <NUM>, <NUM> at the same time. In some cases, pressurized fluid may be supplied through console switch valve <NUM> slightly before being applied to console switch valve <NUM>. That is, console switch valve <NUM> may be opened slightly before console switch valve <NUM>. The pressurized fluid will fill up the chamber <NUM> to cause the diaphragm <NUM> and the inner member <NUM> to move into the distal position. The spring mechanism <NUM> eventually responds to the movement of the inner member <NUM>, thereby causing the slider <NUM> to move into the second position. But, because pressure is being applied through both console switch valves <NUM>, <NUM>, the pressure will be maintained within the chamber <NUM> to keep the inner member <NUM> in the distal position until the pressure is relieved. Pressure may be relieved by switching the console switch valves <NUM>, <NUM> to the vent position. This will allow any fluid within the chamber <NUM> to be vented out. Alternatively, pressure may be relieved by discontinuing pressure through the pressurized fluid supply <NUM>.

To operate the probe <NUM> at a low cut-rate, the console <NUM> can apply a series of pulses of pressurized fluid through the console switch valves <NUM>, <NUM>. Each pulse will cause a single cut as described above. The rate at which the probe <NUM><NUM> operates in non-resonant mode is controlled by adjusting the nature of the pulses of pressurized fluid being supplied through the console switch valves <NUM>, <NUM>.

In some embodiments, such as the embodiment disclosed in <FIG>, <FIG>, and <FIG>, the mode is changed via operation of the console switch valves <NUM>, <NUM>. In accordance with this embodiment, the console <NUM> may include a mode selector input, such as a button, dial, or switch, for example, to enable the system to switch between modes. In some examples, the console operates to automatically select the operational mode based on a selected cut rate, with the console automatically operating in the resonant mode when the cut-rate is set above a threshold and automatically operating in the non-resonant mode when the cut-rate is below a threshold. In some embodiments the mode is determined by the pressure of the fluid being supplied to the probe.

<FIG> is a diagram showing an illustrative dual mode vitrectomy probe <NUM> when the system is operating in a non-resonant mode. According to the present example, the probe <NUM>, includes an actuating element <NUM> having a chamber <NUM> that has a proximal section <NUM> and a distal section <NUM> separated by a diaphragm <NUM>. The sections <NUM>, <NUM> are in fluid connection with a control valve system that forms a part of the probe <NUM>. In one example, the control valve system is a spool valve <NUM>. The spool valve <NUM> is in fluid connection with fluid director such as slide valve <NUM>. The spool valve <NUM> is used to switch the probe <NUM><NUM> between a resonant mode and a non-resonant mode. The spool valve <NUM> is also in fluid connection with fluid supply lines that connect between the probe <NUM> and a console (not shown), such as console <NUM>.

The chamber <NUM> is divided into the proximal section <NUM> and the distal section <NUM>. The diaphragm <NUM> may be disc-shaped to form a seal with the inner wall of the chamber <NUM> so as to seal the distal section <NUM> from the proximal section <NUM>. The diaphragm is secured to the inner member <NUM> such that movement of the diaphragm <NUM> causes movement of the inner member <NUM>. Pumping a fluid into the proximal section <NUM> increases the volume of the proximal section <NUM> and decreases the volume of the distal section <NUM> by pushing fluid out of the distal section <NUM>. Conversely, pumping fluid into the distal section <NUM> increases the volume of the distal section and decreases the volume of the proximal section <NUM> by pressing fluid out of the proximal section <NUM>.

The spool valve <NUM> includes a spool <NUM> that is movable between two positions. As illustrated in <FIG>, the spool <NUM> is biased into a first position by a biasing element <NUM> such as a spring mechanism. The first position is such that fluid from the fluid supply lines <NUM>, <NUM> bypasses the slide valve <NUM> and flows directly into the proximal section <NUM> and the distal section <NUM>.

While in non-resonant mode, the probe <NUM> operates as follows. A controlled amount of pressurized fluid is applied at the console <NUM><NUM> to both fluid supply lines <NUM>, <NUM>. The pressure differential between the two fluid supplies <NUM>, <NUM> is kept below a threshold level in order to keep the spool valve <NUM> in the first position, as illustrated in <FIG>. Pressure pulses are alternatingly applied between fluid supply <NUM> and fluid supply <NUM>. Specifically, to move the inner member <NUM> and close the port <NUM>, a pressure pulse is applied through fluid supply <NUM>. This fluid pulse passes through path <NUM> of the spool valve <NUM>, through line <NUM>, through port <NUM> and into the proximal section <NUM> of the chamber <NUM>. The fluid pulse is sufficient to move the diaphragm <NUM> and press any fluid within the distal section <NUM> out of port <NUM>, through line <NUM>, through path <NUM> of the spool valve <NUM> and back through fluid supply line <NUM>.

To move the inner member <NUM> and open the port <NUM>, a fluid pulse is applied at fluid supply <NUM>. This fluid pulse passes through path <NUM> of the spool valve <NUM>, through line <NUM>, through port <NUM> and into the distal section <NUM> of the chamber <NUM>. The fluid pulse is sufficient to move the diaphragm <NUM> in the distal direction, thereby pressing fluid out of the proximal section <NUM>. Any fluid within the proximal section <NUM> is then pressed out of port <NUM>, through line <NUM>, through path <NUM> of the spool valve <NUM>, and back through fluid supply <NUM>. Thus, by applying controlled, alternating pulses between the fluid supplies <NUM>, <NUM>, the probe can operate at a low cut-rate and even perform single cuts.

<FIG> and <FIG> are diagrams showing an illustrative dual mode vitrectomy probe <NUM> in a resonant mode. <FIG> illustrates stage <NUM> and <FIG> illustrates stage <NUM> of the resonant mode. To put the probe in a resonant mode, the pressure differential between the fluid supplies <NUM>, <NUM> exceeds a threshold level. Specifically, the pressure at fluid supply <NUM> is sufficiently greater than the pressure at fluid supply <NUM> such that the spring force of the biasing element <NUM> is overcome. This moves the spool <NUM> into a second position as illustrated in <FIG> and <FIG>.

With the spool <NUM> in the second position, fluid from fluid supply <NUM> will pass through path <NUM> of the spool valve <NUM>, through line <NUM>, through path <NUM> of the slide valve <NUM>, through line <NUM>, through path <NUM> of the spool valve <NUM>, through line <NUM>, through port <NUM>, and into the proximal chamber <NUM>. This will move the diaphragm <NUM> and the inner member <NUM> so as to close the port <NUM>. This will also press any fluid within the distal chamber <NUM> out of port <NUM>, through line <NUM>, through path <NUM> of the spool valve <NUM>, through line <NUM>, through path <NUM> of the slide valve <NUM>, through line <NUM>, through path <NUM> of the spool valve <NUM>, and out of supply line <NUM>.

The slide valve <NUM> acts as a flow director by directing flow either into or out of either section <NUM>, <NUM>. In one example, the slide valve <NUM> includes a slider <NUM>. The slider <NUM> is connected to the inner member <NUM> with a compressed spring mechanism <NUM> such that movement of the inner member <NUM> causes a delayed movement of the slider <NUM>. When the slider <NUM> changes position, as shown in <FIG>, the pressurized fluid from fluid supply <NUM> is rerouted so as to fill up the distal section <NUM> instead of the proximal section <NUM>. Specifically, fluid from fluid supply <NUM> passes through path <NUM>, through line <NUM>, through path <NUM> of the slider valve <NUM>, through line <NUM>, through path <NUM> of the spool valve <NUM>, through line <NUM>, through port <NUM>, and into the distal section <NUM>. This moves the diaphragm <NUM> and the inner member <NUM> into the proximal position so as to open the port <NUM>. This also presses fluid out of the proximal section <NUM> through the port <NUM>, through line <NUM>, through path <NUM>, through line <NUM>, through path <NUM> of the slide valve <NUM>, through line <NUM>, through path <NUM> of the spool valve <NUM>, and out of fluid supply <NUM>. Movement of the inner member <NUM> will eventually cause movement of the slider <NUM>, which will again reroute the fluid from fluid supply <NUM> to the proximal section <NUM>, thereby repeating the cycle.

While the present embodiment utilizes a spool valve <NUM>, other types of valves that can switch fluid pathways are contemplated. Additionally, the slide valve <NUM> may be one of a variety of valves that are able to switch fluid pathways, including a spool valve.

While the embodiments described above and illustrated in the corresponding figures relate to a probe that cuts fibers by opening and closing the ports, it is understood that principles described herein may be applied to other types of cutters as well. In some examples, motion of an inner member does not open and close the port. Rather, motion of the inner member moves a cutter that moves across the port to cut tissue but does not actually open or close the port.

<FIG> is a graph <NUM> showing a relationship between applied pressure and probe cut-rate. The vertical axis <NUM> of the graph represents pressure. The horizontal axis <NUM> of the graph <NUM> represents time. The dotted line <NUM> represents a threshold pressure level.

The graph illustrates the applied pressure as a function of time. In the first mode <NUM>, single cuts are made by applying a single pulse of pressure. The single cut may be initiated by a control mechanism associated with the console, or may be initiated by a control mechanism on the hand-piece of the probe. In some examples, a foot pedal may be connected to the console, that when pressed by an operator of the probe, causes a single pulse to be delivered to the probe. The single pulse of fluid causes the probe to perform a single cut.

In the second mode <NUM>, the console causes a series of pulses to be applied to the probe to operate the probe at a low cut-rate. For example, the low cut-rate may range from <NUM> to <NUM>,<NUM> cuts per minute. The probe <NUM> may be set to operate in the low cut-rate mode <NUM> through a control mechanism associated with the console.

When using the probe <NUM> in the single cut mode <NUM> or the low cut-rate mode <NUM>, the pressure associated with the pulses is less than a threshold level. The threshold level is the level that when exceeded, causes the probe to operate in resonant mode. For example, in the embodiment described above in relation to <FIG>, <FIG>, and <FIG>, applying pressure higher than the threshold level causes the spool valve <NUM> to switch positions, thus putting the probe <NUM> into resonant mode <NUM>. In one example, the speed at which the probe operates in resonant mode is substantially higher than the speed at which the probe operates in the low cut-rate mode. For example, the resonant mode <NUM> may involve a speed within a range of about <NUM>,<NUM> to <NUM>,<NUM> cuts per minute.

<FIG> is a graph <NUM> showing the position of the inner member <NUM> of the probe in accordance with the graph of <FIG>. The vertical axis <NUM> represents the position of the inner member <NUM>. The horizontal axis <NUM> represents time and corresponds with the time in the horizontal axis of <FIG>. In this example, the inner member <NUM> has a default position of the proximal position <NUM>, wherein the port <NUM> is open. When a pulse of fluid is supplied to the probe <NUM>, the inner member <NUM> moves to the distal position <NUM>, wherein the port <NUM> is closed. Thus, a pulse <NUM> of fluid corresponds with the inner member temporarily being in the distal position <NUM>.

<FIG> is a diagram showing an ophthalmic surgical system with dual mode vitrectomy probe. According to the present example, the system <NUM> includes a console <NUM> and a hand piece <NUM>. The console <NUM> includes a control system <NUM> and a pressurized fluid source <NUM>. The hand piece <NUM> may be the same probe <NUM> discussed above, or may be another probe used by an operator or surgeon to treat a condition of the eye. In this example, the distal portion is inserted into the eye of a patient <NUM>.

The console <NUM> includes all the necessary components to drive and work with the hand piece <NUM>. Additional components and features of the console would be apparent to one of ordinary skill in the art. The control system <NUM> within the console <NUM> provides the desired signals to the hand piece <NUM> to cause the inner member to move with respect to the sleeve member and cut vitreous fibrils.

The pressurized fluid source <NUM> may include a chamber of fluid under pressure. The fluid may be a liquid or a gas such as atmospheric air. The pressurized fluid source may be adjusted to apply different levels of pressurized fluid to the hand piece <NUM>. Specifically, the pressurized fluid source <NUM> may apply a steady pressure. Or, the pressurized fluid source <NUM> may apply pulses of fluid to the hand piece <NUM>.

<FIG> is a flowchart showing an illustrative method for treating a patient with dual mode vitrectomy probe. According to the present example, the method <NUM> includes creating an incision in an eye of a patient at <NUM>. At <NUM>, the method <NUM> includes inserting a vitrectomy probe into the eye of the patient.

According to some examples, the probe includes a dual mode actuating element as described above. The probe also includes a cutting element having a hollow sleeve member extending distally from the body and an inner member within the hollow sleeve member.

At <NUM>, the method <NUM> includes operating the probe in a resonant mode. In the resonant mode, a constant supply of pressurized fluid is applied to the probe. The actuating element within the probe then moves back and forth under that applied pressure. For example, movement of the actuating element moves the inner member, thus opening and closing the port at the end of the hollow sleeve member.

At <NUM>, the method <NUM> includes operating the probe in a non-resonant mode. In the non-resonant mode, one or more pulses of pressurized fluid are supplied to the probe to cause the probe to perform a single cut or to operate at a low cut-rate. Thus, the operator of the probe has multiple options when performing a surgical operation. Specifically, the operator may change the mode as desired to effectively remove vitreous fibrils from the eye of the patient.

Claim 1:
An ophthalmic surgical system (<NUM>, <NUM>) for treating an eye of a patient, the system comprising:
a body (<NUM>);
a cutting element (<NUM>) extending distally from the body including:
a sleeve member (<NUM>) comprising a port (<NUM>) at an end;
an inner member (<NUM>) disposed within the sleeve member, the inner member being movable axially with respect to the sleeve member; and
an actuating element (<NUM>) secured to the inner member, the actuating element configured for operation in both a resonant mode and a non-resonant mode;
wherein, in operation in the resonant mode, application of a constant supply of pressurized fluid causes reciprocal movement of the inner member, and wherein, in operation in the non-resonant mode, movement of the inner member is in accordance with a pulse of pressurized fluid,
wherein the actuating element (<NUM>) comprises:
a chamber (<NUM>, <NUM>);
a diaphragm (<NUM>, <NUM>) movable within the chamber and secured to the inner member (<NUM>); characterised in that the actuating element further comprises
a flow director (<NUM>, <NUM>) comprising a slide valve in fluid connection with the chamber, the slide valve being in connection with the inner member such that movement of the inner member switches the slide valve in a delayed manner.