Patent Description:
Conventional vitrectomy probes can be divided into two types: axial or "guillotine style" probes and rotational probes. An axial or guillotine style probe has an inner cutting member (also referred to as a "cutter") that reciprocates in a translational manner along its longitudinal axis. The inner cutting member is positioned within an outer cutting member that includes a port at its distal end. Vitreous and/or membranes are aspirated into the open port of the outer cutting member. The vitreous and/or membranes are sheared as the inner cutting member reciprocates. The cut tissue is then aspirated away from the eye. The inner cutting member may reciprocate at a rate between several tens to several hundred times per second.

A rotational or rotary probe has an inner cutting member that rotates at a high rate around its longitudinal axis. In general, rotational probes use either continuous or reciprocating rotation (e.g., using limited rotary action drive mechanisms that limit angular rotation) of the inner cutting member. Undesired winding and/or tearing (as opposed to cutting) of the fibrils may occur with the use of continuous rotation.

During axial or rotational reciprocation of the cutter as described above, an undesirable pumping action or pulse flow may be produced through the port in the distal end of the outer cutting member. The pulse flow pushes fluid out of the port as the inner cutting member moves towards the port and draws additional fluid into the port as the inner cutting member moves away from the port. In certain cases, the pulse flow can damage the retina, lens capsule or iris, especially when pulling on collagen fibrils attached to the peripheral retina.

In both types of vitrectomy probes, the cutter is powered by a pneumatic vitrectomy machine (also referred to as a "surgical console") including one or more high-speed pneumatic solenoid valves (also referred to as "drive valves"). The cutter may be powered by pressurized air that is alternately directed to two output ports of the surgical console through action of the solenoid valves. The air pressure pulses are carried from the output ports of the surgical console through multiple feet of elastomeric tubing before being applied to a corresponding chamber of the actuator for driving reciprocating motion of the cutter. Unfortunately, the solenoid valves increase the cost and noise of the surgical console, and vibration of the tubing produces additional noise and heat. In addition, by the time the air pressure pulses reach the actuator, substantial pulse broadening has occurred which further exacerbates the issues related to pulse flow within the eye as described above.

Therefore, there is a need for improved vitrectomy probes that address at least some of the disadvantages outlined above.

Reference is made to the documents <CIT>, <CIT>, <CIT> and <CIT> which have been cited as exemplary of the background state of the art.

The present disclosure relates generally to a vitrectomy probe.

Certain embodiments described herein provide a vitrectomy probe including a housing, an actuator disposed inside the housing, a cutter coupled to the actuator and extending from the housing and an air turbine disposed inside the housing. The vitrectomy probe includes a valve body interfacing with the rotor. The air turbine includes a rotor and a plurality of turbine blades coupled to the rotor. During rotation of the air turbine, air is selectively routed to and from the actuator according to a rotational position of the rotor in relation to the valve body, thereby reciprocating the cutter.

As described above, conventional vitrectomy probes rely on valving in the surgical console to alternately direct air pressure pulses through two corresponding lengths of tubing, which increases cost and noise of the surgical console, produces additional noise and heat within the tubing, and results in substantial air pressure pulse broadening which further exacerbates the issues related to pulse flow within the eye. Certain embodiments described in the present disclosure attempt to overcome these deficiencies by providing a vitrectomy probe with an air turbine driven rotary valve, thereby replacing the pneumatic valves in the surgical console. In certain embodiments, relocating the valving from the surgical console to the vitrectomy probe reduces or prevents broadening of the air pressure pulses that normally occurs in the elastomeric tubing. In addition, vibration of the elastomeric tubing due to the air pressure pulses is also reduced or prevented. In certain embodiments, higher cutting rates can mitigate pulse flow induced damage by reducing a distance over which the fibers are pulled prior to being sheared by the cutter.

<FIG> illustrates a cross-sectional view of a vitrectomy probe <NUM>, according to certain embodiments. <FIG> illustrates a partial cut-away isometric view of vitrectomy probe <NUM> of <FIG>, according to certain embodiments. <FIG> and <FIG> are, therefore, described together herein for clarity.

Vitrectomy probe <NUM> generally includes a housing <NUM>, an air turbine <NUM> disposed inside housing <NUM>, a valve body <NUM> disposed inside housing <NUM>, an actuator <NUM> disposed inside housing <NUM>, and a cutter <NUM> coupled to actuator <NUM> and extending from housing <NUM>. As shown in <FIG>, housing <NUM>, air turbine <NUM>, valve body <NUM>, actuator <NUM> and cutter <NUM> are axially aligned parallel to center axis <NUM>. Vitrectomy probe <NUM> is coupled to an air supply source <NUM> through a length of tubing <NUM>, such as elastomeric tubing. The flow of air through tubing <NUM> is regulated by an air supply valve <NUM> that is actuated using a controller <NUM>. In certain embodiments, air supply valve <NUM> is a pneumatic flow control valve for regulating output flow. In certain embodiments, air supply source <NUM>, air supply valve <NUM>, and controller <NUM> are disposed in or coupled to a surgical console.

As shown in <FIG>, housing <NUM> includes a single inlet <NUM> and a single outlet <NUM>. Inlet <NUM> is in fluid communication with air turbine <NUM>, valve body <NUM>, and actuator <NUM>. In general, rotation of air turbine <NUM> is driven by air flow from inlet <NUM> to actuator <NUM>, as described in more detail below. In practice, an actuation rate of cutter <NUM> is adjusted based on air pressure applied to inlet <NUM>. Outlet <NUM> is in fluid communication with actuator <NUM> for exhausting air from actuator <NUM>.

Air turbine <NUM> generally includes a rotor <NUM> and a plurality of turbine blades <NUM> coupled to rotor <NUM>. Rotor <NUM> and valve body <NUM> collectively form a valve mechanism (also referred to as a "rotary valve") having an interface that regulates air flow to actuator <NUM> for reciprocating cutter <NUM>. The movable part of the valve mechanism is integral with rotor <NUM>. Therefore, during rotation of air turbine <NUM>, air is selectively routed to and from actuator <NUM> according to a rotational position of rotor <NUM> in relation to valve body <NUM>. In other words, the rotational position of rotor <NUM> in relation to valve body <NUM> controls air flow through the interface of the valve mechanism. Operation of the valve mechanism is described in more detail below. An outer surface <NUM> of rotor <NUM> is sealed with housing <NUM> to prevent fluid communication between inlet <NUM> and outlet <NUM>. In the illustrated embodiments, sealing is provided by O-ring seal <NUM>. However, other sealing mechanisms are also contemplated.

Valve body <NUM> has multiple apertures that are configured to route air from a distal end of rotor <NUM> to a corresponding chamber of actuator <NUM>. In the illustrated embodiments, valve body <NUM> is coupled to housing <NUM>. Alternatively, valve body <NUM> may be integral with housing <NUM>. Valve body <NUM> is described in more detail below with respect to <FIG>.

Actuator <NUM> generally includes a diaphragm <NUM> coupled to cutter <NUM>, a first chamber 154a located on a first side of diaphragm <NUM>, and a second chamber 154b located on a second opposite side of diaphragm <NUM>. First chamber 154a is in fluid communication with a corresponding aperture of valve body <NUM> through a first flow line 156a. Likewise, second chamber 154b is in fluid communication with a corresponding aperture of valve body <NUM> through a second flow line 156b. Thus, by controlling the rotational position of rotor <NUM> in relation to valve body <NUM>, air from inlet <NUM> is selectively fed to either first or second chamber 154a-b of actuator <NUM> while air within the opposite chamber is simultaneously exhausted to outlet <NUM>, as described in more detail below.

A proximal end of cutter <NUM> is coupled to actuator <NUM>. A distal end of cutter <NUM> extends from housing <NUM>. The distal end of cutter <NUM> is disposed inside an outer cutting member <NUM>, which extends from a distal end of housing <NUM>. Cutter <NUM> reciprocates in a direction parallel to center axis <NUM> as differential air pressure is applied to first and second chambers 154a-b of actuator <NUM>, as described in more detail below. A port <NUM> is disposed in a radial wall of outer cutting member <NUM>. Vitreous and/or membranes are aspirated into port <NUM> during cutting. The vitreous and/or membranes are sheared as cutter <NUM> reciprocates inside outer cutting member <NUM>. The cut tissue is then aspirated away from the eye. Vitrectomy probe <NUM> comprises an axial or "guillotine style" probe in which actuator <NUM> and cutter <NUM> reciprocate in a direction parallel to center axis <NUM>. Embodiments of the present disclosure may also be used with a rotary probe having an actuator and cutter that reciprocate in a circumferential direction about center axis <NUM>.

<FIG> illustrates an enlarged cross-sectional view of a portion of vitrectomy probe <NUM> of <FIG>, according to certain embodiments. As shown in <FIG>, a first flow path <NUM> is disposed in rotor <NUM>. First flow path <NUM> extends from a first radial opening 120a in outer surface <NUM> to a first distal opening 120b in a distal end <NUM> of rotor <NUM>. First flow path <NUM> is further illustrated in <FIG>. First radial opening 120a is located in a proximal direction in relation to O-ring seal <NUM>. Note that, as described herein, a proximal end or portion of the component refers to the end or the portion that is distanced further away from the patient's body during use thereof. On the other hand, a distal end or portion of a component refers to the end or the portion that is closer to a patient's body. First flow path <NUM> is in fluid communication with inlet <NUM> through a first annulus <NUM>. First annulus <NUM> is disposed radially between outer surface <NUM> of rotor <NUM> and housing <NUM> to maintain continuous fluid coupling between inlet <NUM> and first flow path <NUM> at each possible rotational position of rotor <NUM>.

A second flow path <NUM> is disposed in rotor <NUM>. Like first flow path <NUM>, second flow path <NUM> extends from a second radial opening 126a in outer surface <NUM> to a second distal opening 126b in distal end <NUM> of rotor <NUM>. Second radial opening 126a is located in a distal direction in relation to O-ring seal <NUM>. As shown in <FIG>, first radial opening 120a and second radial opening 126a are located <NUM>° apart on rotor <NUM>. In some other embodiments, the radial openings are aligned parallel to center axis <NUM> of rotor <NUM>. Second flow path <NUM> is in fluid communication with outlet <NUM> through second annulus <NUM>. Second flow path <NUM> is fluidly isolated from inlet <NUM>. Like first annulus <NUM>, second annulus <NUM> is disposed radially between outer surface <NUM> of rotor <NUM> and housing <NUM> to maintain continuous fluid coupling between second flow path <NUM> and outlet <NUM> at each possible rotational position of rotor <NUM>.

A proximal end <NUM> of valve body <NUM> is in air-tight contact with distal end <NUM> of rotor <NUM>. A first aperture <NUM> in proximal end <NUM> of valve body <NUM> is in fluid communication with first flow line 156a. A second aperture <NUM> in proximal end <NUM> of valve body <NUM> is in fluid communication with second flow line 156b.

<FIG> illustrates a cross-sectional view taken along section line 1E-1E of <FIG>, according to certain embodiments. As shown in <FIG>, first aperture <NUM> and second aperture <NUM> each comprise arc-shaped segments located on radially opposite sides of proximal end <NUM> of valve body <NUM>. First aperture <NUM> and second aperture <NUM> each have an angle of about <NUM> degrees to about <NUM> degrees.

<FIG> illustrates a cross-sectional view taken along section line 1F-1F of <FIG>, according to certain embodiments. As shown in <FIG>, first distal opening 120b and second distal opening 126b of rotor <NUM> each comprise arc-shaped segments having an angle of about <NUM> degrees to about <NUM> degrees. First distal opening 120b and second distal opening 126b are located on radially opposite sides, or <NUM>° apart, on distal end <NUM>.

Referring collectively to <FIG>, operation of vitrectomy probe <NUM> is described below. When rotor <NUM> is in the position illustrated, first flow path <NUM> of rotor <NUM> is in fluid communication with first aperture <NUM> of valve body <NUM>, thereby supplying air to first chamber 154a of actuator <NUM> to move cutter <NUM> in a proximal direction in relation to housing <NUM>. When rotor <NUM> is in the position illustrated, outlet <NUM> of housing <NUM> is in fluid communication with second chamber 154b of actuator <NUM>. In this position, air within second chamber 154b is exhausted through second aperture <NUM> of valve body <NUM>, through second flow path <NUM> of rotor <NUM>, and subsequently through outlet <NUM> of housing <NUM>.

When rotor <NUM> is rotated <NUM>° from the position illustrated, first flow path <NUM> of rotor <NUM> is in fluid communication with second aperture <NUM> of valve body <NUM>, thereby supplying air to second chamber 154b of actuator <NUM> to move cutter <NUM> in a distal direction in relation to housing <NUM>. When rotor <NUM> is rotated <NUM>° from the position illustrated, outlet <NUM> of housing <NUM> is in fluid communication with first chamber 154a of actuator <NUM>. In this position, air within first chamber 154a is exhausted through first aperture <NUM> of valve body <NUM>, through second flow path <NUM> of rotor <NUM>, and subsequently through outlet <NUM> of housing <NUM>.

<FIG> illustrates a cross-sectional view of another vitrectomy probe <NUM>, according to certain embodiments. <FIG> illustrates a partial cut-away isometric view of vitrectomy probe <NUM> of <FIG>, according to certain embodiments. <FIG> and <FIG> are, therefore, described together herein for clarity.

Vitrectomy probe <NUM> has separate flow paths for independently driving air turbine <NUM> and actuator <NUM>. This is in contrast to vitrectomy probe <NUM> described above, in which air turbine <NUM> and actuator <NUM> are both driven by the same air flow coming from inlet <NUM>. As shown in <FIG>, vitrectomy probe <NUM> is coupled to air supply source <NUM> through a second length of tubing <NUM>. The flow of air through tubing <NUM> is regulated by a second air supply valve <NUM> that is actuated using controller <NUM>. In certain embodiments, second air supply valve <NUM> is a pneumatic flow control valve for regulating output flow similar to air supply valve <NUM>. In certain embodiments, air supply valve <NUM> is disposed in or coupled to a surgical console. As shown in <FIG>, housing <NUM> includes a first inlet <NUM> and a first outlet <NUM> in fluid communication with first inlet <NUM>. First inlet <NUM> and first outlet <NUM> are in fluid communication with blades <NUM> of air turbine <NUM>. In general, rotation of air turbine <NUM> is driven by air flow from first inlet <NUM> to first outlet <NUM> through first annulus <NUM>. First annulus <NUM> is disposed radially between outer surface <NUM> of rotor <NUM> and housing <NUM>. In practice, an actuation rate of cutter <NUM> is adjusted based on air pressure applied to first inlet <NUM>.

Housing <NUM> includes a second inlet <NUM> fluidly isolated from first inlet <NUM> and first outlet <NUM>. Outer surface <NUM> of rotor <NUM> is sealed with housing <NUM> to prevent fluid communication between second inlet <NUM> and either of first inlet <NUM> or first outlet <NUM>. Second inlet <NUM> is provided for supplying air to actuator <NUM>. Housing <NUM> further includes a second outlet <NUM> for exhausting air from actuator <NUM>. Note that, when viewing vitrectomy probe <NUM> as shown in <FIG>, second outlet <NUM> of housing <NUM> is oriented into the plane of the page as shown more clearly in <FIG>.

<FIG> illustrates an enlarged cross-sectional view of a portion of vitrectomy probe <NUM> of <FIG>, according to certain embodiments. As shown in <FIG>, a first flow path <NUM> disposed in rotor <NUM> is in fluid communication with second inlet <NUM>, which is in contrast to the design of vitrectomy probe <NUM> (shown in <FIG>). First flow path <NUM> extends from a first radial opening 220a in outer surface <NUM> to a first distal opening 220b in a distal end <NUM> of rotor <NUM>. First flow path <NUM> is further illustrated in <FIG>. First radial opening 220a is located in a distal direction in relation to O-ring seal <NUM>. First flow path <NUM> is in fluid communication with second inlet <NUM> through second annulus <NUM>. Second annulus <NUM> is disposed radially between outer surface <NUM> of rotor <NUM> and housing <NUM> to maintain continuous fluid coupling between second inlet <NUM> and first flow path <NUM> at each possible rotational position of rotor <NUM>.

A second flow path <NUM> is disposed in distal end <NUM> of rotor <NUM>. Second flow path <NUM> is fluidly isolated from second inlet <NUM>. In contrast to vitrectomy probe <NUM> (shown in <FIG>), second flow path <NUM> does not extend to outer surface <NUM>. Instead, second flow path <NUM> consists of a single distal opening having a first portion 226a and a second portion 226b located radially inwardly of first portion 226a. Second portion 226b is located at a radial center of rotor <NUM>. Valve body <NUM> has a third aperture <NUM> formed in proximal end <NUM>, which is aligned axially with second portion 226b of second flow path <NUM>. Third aperture <NUM> is in fluid communication with second outlet <NUM> of housing <NUM>. Because second portion 226b and third aperture <NUM> are each located on center axis <NUM>, fluid communication is maintained therebetween at each possible rotational position of rotor <NUM>, thereby enabling air to be continuously exhausted through second outlet <NUM>.

<FIG> illustrates a cross-sectional view taken along section line 2E-2E of <FIG>, according to certain embodiments. As shown in <FIG>, first aperture <NUM> and second aperture <NUM> each comprise arc-shaped segments located on radially opposite sides of proximal end <NUM> of valve body <NUM>. First aperture <NUM> and second aperture <NUM> each have an angle of about <NUM> degrees to about <NUM> degrees. In the illustrated embodiments, third aperture <NUM> is round.

<FIG> illustrates a cross-sectional view taken along section line 2F-2F of <FIG>, according to certain embodiments. As shown in <FIG>, first distal opening 220b and first portion 226a of second flow path <NUM> each comprise arc-shaped segments having an angle of about <NUM> degrees to about <NUM> degrees. First distal opening 220b and first portion 226a are located on radially opposite sides, or <NUM>° apart, on distal end <NUM>. In the illustrated embodiments, second portion 226b of second flow path <NUM> has a round shape corresponding to that of third aperture <NUM> of valve body <NUM>.

Referring collectively to <FIG>, operation of vitrectomy probe <NUM> is described below. When rotor <NUM> is in the position illustrated, first flow path <NUM> of rotor <NUM> is in fluid communication with first aperture <NUM> of valve body <NUM>, thereby supplying air to first chamber 154a of actuator <NUM> to move cutter <NUM> in a proximal direction in relation to housing <NUM>. When rotor <NUM> is in the position illustrated, second outlet <NUM> of housing <NUM> is in fluid communication with second chamber 154b of actuator <NUM>. In this position, air within second chamber 154b is exhausted through second aperture <NUM> of valve body <NUM>, through second flow path <NUM> of rotor <NUM>, and subsequently through third aperture <NUM> of valve body <NUM>.

When rotor <NUM> is rotated <NUM>° from the position illustrated, first flow path <NUM> of rotor <NUM> is in fluid communication with second aperture <NUM> of valve body <NUM>, thereby supplying air to second chamber 154b of actuator <NUM> to move cutter <NUM> in a distal direction in relation to housing <NUM>. When rotor <NUM> is rotated <NUM>° from the position illustrated, second outlet <NUM> of housing <NUM> is in fluid communication with first chamber 154a of actuator <NUM>. In this position, air within first chamber 154a is exhausted through first aperture <NUM> of valve body <NUM>, through second flow path <NUM> of rotor <NUM>, and subsequently through third aperture <NUM> of valve body <NUM>.

<FIG> illustrates a cross-sectional view of yet another vitrectomy probe <NUM>, according to certain embodiments. Vitrectomy probe <NUM> combines elements of certain embodiments described above. In particular, vitrectomy probe <NUM> has separate flow paths for independently driving air turbine <NUM> and actuator <NUM> like vitrectomy probe <NUM>. However, instead of exhausting air from actuator <NUM> into rotor <NUM> and back through valve body <NUM>, air is exhausted through outer surface <NUM> of rotor <NUM> similar to vitrectomy probe <NUM>. More particularly, vitrectomy probe <NUM> differs from vitrectomy probe <NUM> in that second flow path <NUM> extends from a second radial opening 326a in outer surface <NUM> to a second distal opening 326b in distal end <NUM> of rotor <NUM>. Second flow path <NUM> is in fluid communication with second outlet <NUM> through a third annulus <NUM>. Second flow path <NUM> is fluidly isolated from second inlet <NUM> by O-ring seal <NUM>. Like second annulus <NUM>, third annulus <NUM> is disposed radially between outer surface <NUM> of rotor <NUM> and housing <NUM> to maintain continuous fluid coupling between second flow path <NUM> and second outlet <NUM> at each possible rotational position of rotor <NUM>.

Operation of vitrectomy probe <NUM> is described below. When rotor <NUM> is in the position illustrated, first flow path <NUM> of rotor <NUM> is in fluid communication with first aperture <NUM> of valve body <NUM>, thereby supplying air to first chamber 154a of actuator <NUM> to move cutter <NUM> in a proximal direction in relation to housing <NUM>. When rotor <NUM> is in the position illustrated, second outlet <NUM> of housing <NUM> is in fluid communication with second chamber 154b of actuator <NUM>. In this position, air within second chamber 154b is exhausted through second aperture <NUM> of valve body <NUM>, through second flow path <NUM> of rotor <NUM>, and subsequently through second outlet <NUM> of housing <NUM>.

When rotor <NUM> is rotated <NUM>° from the position illustrated, first flow path <NUM> of rotor <NUM> is in fluid communication with second aperture <NUM> of valve body <NUM>, thereby supplying air to second chamber 154b of actuator <NUM> to move cutter <NUM> in a distal direction in relation to housing <NUM>. When rotor <NUM> is rotated <NUM>° from the position illustrated, second outlet <NUM> of housing <NUM> is in fluid communication with first chamber 154a of actuator <NUM>. In this position, air within first chamber 154a is exhausted through first aperture <NUM> of valve body <NUM>, through second flow path <NUM> of rotor <NUM>, and subsequently through second outlet <NUM> of housing <NUM>.

Claim 1:
A vitrectomy probe (<NUM>, <NUM>), comprising:
a housing (<NUM>, <NUM>);
an actuator (<NUM>, <NUM>) disposed inside the housing (<NUM>, <NUM>);
a cutter (<NUM>) coupled to the actuator (<NUM>) and extending from the housing (<NUM>);
an air turbine (<NUM>) disposed inside the housing (<NUM>), the air turbine comprising:
a rotor (<NUM>); and
a plurality of turbine blades (<NUM>) coupled to the rotor (<NUM>); and
a valve body (<NUM>) interfacing with the rotor (<NUM>), wherein during rotation of the air turbine (<NUM>), air is selectively routed to and from the actuator according to a rotational position of the rotor (<NUM>) in relation to the valve body (<NUM>), thereby reciprocating the cutter (<NUM>).