Patent Description:
A cataract is a clouding and hardening of the eye's natural lens, a structure which is positioned behind the cornea, iris and pupil. The lens is mostly made up of water and protein and as people age these proteins change and may begin to clump together obscuring portions of the lens. To correct this a physician may recommend phacoemulsification cataract surgery. Before the procedure the surgeon numbs the area with anesthesia. Then a small incision is made in the cornea of the eye. Fluids are injected into this incision to support the surrounding structures. The anterior surface of the lens capsule is then removed to gain access to the cataract. The surgeon then uses a phacoemulsification probe, which has an ultrasonic handpiece with a titanium or steel needle. The tip of the needle vibrates at ultrasonic frequency to sculpt and emulsify the cataract, while a pump device aspirates particles from the cataract through the tip. The pump is typically controlled with a microprocessor. The pump may be a peristaltic or a venturi type of pump. Aspirated fluids are replaced with irrigation of a balanced salt solution to maintain the anterior chamber of the eye. After removing the cataract with phacoemulsification, the softer outer lens cortex is removed with suction. An intraocular lens (IOL) is introduced into the empty lens capsule. Small struts called haptics help hold the IOL in place. Once correctly implanted the IOL restores the patient's vision.

<CIT>describes an ophthalmic curette, which includes a handle, a neck portion, a curette head, a light-emitting diode (LED) lamp, a button cell groove and a switch. The neck portion is connected with the handle, the curette head is connected with the neck portion, the LED lamp is mounted on the handle, and the button cell groove is connected with the LED lamp and the switch through wires.

<CIT> describes a curette used for ophthalmology and comprises a curette head, a curette neck, a curette handle, and an injector connector, wherein the curette head is a circular spoon-shaped deboss structure. The curette neck and the curette handle are both of a hollow tubular structure. An opening is arranged at the front end of the curette neck. The back end of the curette handle is provided with the injector connector, and the injector connector can be connected with an injector so as to conveniently inject irrigation liquid and medicine into a diseased portion. By means of the curette, the diseased position can be irrigated or injected with the medicine after diseased tissue is scraped off.

<CIT>describes a curette used in debridement and removal of skin, tissue, and necrotic debris from wound beds comprising a pinchable cap and a circular metal cutting end, wherein an individual may apply pressure to the cap, covering the metal cutting end, in order to manipulate the cutting end into a shape to debride narrow or smaller portions of a wounds such as a narrow oval. The curette also includes a measurement scale, a depth probe that also acts as a packing tool, and finger grips. An optional LED or LEDs may be included in or on the curette.

<CIT> describes a surgical cutting instrument comprising an outer tube having a peripheral wall and a longitudinal axis. The outer tube has a plurality of openings arranged generally longitudinally along the outer tube. Each of the openings has first and second cutting edges defining portions of the periphery of such opening. Each of the first cutting edges is substantially straight as viewed in a particular direction perpendicular to the longitudinal axis of the outer tube. An inner cutting member to rotatable within the outer tube. The inner cutting member has a cutting edge cooperable with the first and second cutting edges of the openings of the outer tube for cutting material from within the patient with a shearing action.

There is provided in accordance with the present invention, an ophthalmic curette device according to independent claim <NUM>.

Additionally, in accordance with an embodiment of the present disclosure the magnetic position sensor includes at least one coil.

Moreover, in accordance with an embodiment of the present disclosure the tube has a minimum length of <NUM>.

Further in accordance with an embodiment of the present disclosure the tube has an outer diameter between <NUM> and <NUM>.

Still further in accordance with an embodiment of the present disclosure the tube has a wall thickness between <NUM> and <NUM>.

Additionally, in accordance with an embodiment of the present disclosure, the device includes a loop or hook connected to the distal end of the tube.

Moreover, in accordance with an embodiment of the present disclosure, the device includes a processor configured to compute a pressure value responsively to the signal provided by the pressure sensor, and a display configured to render the pressure value.

Further in accordance with an embodiment of the present disclosure the processor is disposed in the handle, and the display is disposed on the handle.

There is also provided in accordance with another embodiment of the present disclosure, an ophthalmic curette device, including a handle having a distal end, a tube having a proximal end connected to the distal end of the handle, and having a distal end, and configured to be inserted through a cataract incision into a chamber of an eye of a living subject, and a temperature sensor disposed inside the tube at the distal end of the tube and configured to provide a signal responsively to a temperature inside the chamber of the eye.

Still further in accordance with an embodiment of the present disclosure, the device includes a magnetic position sensor disposed inside the tube.

Moreover, in accordance with an embodiment of the present disclosure, the device includes a processor configured to compute a temperature value responsively to the signal provided by the temperature sensor, and a display configured to render the temperature value.

During cataract surgery, a phacoemulsification probe is typically used with an ophthalmic curette to assist in removal of the cataract from the eye. The curette and the phacoemulsification probe require separate incisions into the eye. However, to make measurements on the eye during the surgery, such as measuring intraocular pressure and/or temperature, different probes need to be used.

Embodiments of the present invention solve the above problems by providing an ophthalmic curette which includes a tube at its distal end for being inserted through a cataract incision into a chamber of an eye of a living subject. One or more sensors are placed inside the tube, typically at its distal end, in order to take pressure and/or temperature readings in the chamber. The ophthalmic curette may therefore be used to manipulate cataract material during a procedure as well as provide pressure and/or temperature readings thereby removing the need for further tools to be used and/or further incisions. In some embodiments, a position sensor may be placed in the tube, so that the distal end of the curette may be tracked using a position tracking system.

Some embodiments include an ophthalmic curette device, which includes a handle and a tube (for example, a polymer tube or a metal tube such as a rigid biocompatible metal tube) having a proximal end connected to a distal end of the handle. The distal end of the tube is inserted through a cataract incision into a chamber of an eye of a living subject. The tube may have any suitable cross-section shape for example, circular, elliptical, or rectangular. The tube may have any suitable form. In some embodiments, the tube is straight. In other embodiments, the tube is bent or curved. The tube may be formed from any suitable material, e.g., a polymer such as Polyether ether ketone (PEEK) or fluorinated ethylene propylene (FEP), or a metal such as stainless steel or titanium.

In some embodiments, the device also includes a pressure sensor placed inside the distal end of tube, and provides a signal responsively to intraocular pressure inside the chamber of the eye. In some embodiments, the device includes a temperature sensor placed inside the distal end of the tube and provides a signal responsively to a temperature inside the chamber of the eye.

In some embodiments, the device includes a magnetic position sensor placed inside the tube. The magnetic position sensor may be configured to track a position (e.g., location and/or orientation) of the distal end of the device. For example, magnetic field generators generating an alternating magnetic field may be placed around the neck and/or head of the living subject. The generated fields are then detected by the magnetic position sensor which provides a signal indicative of the position of the distal end with respect to the magnetic field generators. The magnetic position sensor may enable the device to be used as a tool during robotic guided surgery.

The tube may have any suitable length, which is long enough for the tube to be inserted into the eye and be maneuvered during the medical procedure. In some embodiments, the tube has a minimum length of <NUM>. The tube may have any suitable outer diameter and wall thickness. In some embodiments, the tube has an outer diameter between <NUM> and <NUM>, and a wall thickness between <NUM> and <NUM>.

The device optionally includes a processor and a display. In some embodiments, the processor is configured to compute a pressure value responsively to the signal provided by the pressure sensor. In some embodiments, the processor is configured to compute a temperature value responsively to the signal provided by the temperature sensor. The display is configured to render the pressure value and/or the temperature value. In an embodiment, the processor and the display may be disposed in the handle. In some embodiments, a display may also be disposed in a remote console, which is connected to the handle wirelessly and/or via wires, to also render the pressure value and/or the temperature value. The handle and the console may each include an interface to provide data communication between the handle and the console. In an embodiment, a processor may be disposed in the handle or the console. In other embodiments, the display and/or the processor are not included in the handle or the console.

In some embodiments, the sensor signal(s) and/or computed temperature and/or pressure values are conveyed via wires and/or wirelessly to a remote processing device which processes the sensor signals and/or uses the computed temperature and/or pressure values as part of a medical procedure process. For example, medical procedure parameters such as phacoemulsification probe needle vibration frequency, amplitude, and/or mode may be adjusted according to the temperature and/or pressure values.

Reference is now made to <FIG>, which is a partly pictorial, partly block diagram view of an ophthalmic curette device <NUM> constructed and operative in accordance with an embodiment of the present invention.

The ophthalmic curette device <NUM> includes a handle <NUM> having a distal end <NUM>. The handle <NUM> may be formed from any suitable material or combination of materials, for example, a metal and/or polymer.

The ophthalmic curette device <NUM> includes a tube <NUM> having a proximal end <NUM> connected to the distal end <NUM> of the handle <NUM>. The tube <NUM> may have any suitable form. In some embodiments, the tube <NUM> is straight. In other embodiments, the tube <NUM> is bent or curved to any suitable angle, as shown in <FIG>. The tube <NUM> may be formed from any suitable metal, for example, stainless steel or titanium. In some embodiments, the tube <NUM> may be replaced by a tube of any suitable material, for example, a polymer such as PEEK or FEP. Suitable metal and polymer tubing are commercially available from IDEX corporation, Lake Forest, Illinois, USA.

A proximal portion of the tube <NUM> is optionally surrounded by an elongated supporting member <NUM> to provide additional support to the proximal portion which is not inserted into an eye. The supporting member <NUM> may be formed from any suitable material, for example, a metal such as stainless steel or titanium, or a polymer. The tube <NUM> has a distal end <NUM>.

Reference is now made to <FIG>, which is a schematic view of the device <NUM> of <FIG> being inserted into an eye <NUM> of a living subject.

<FIG> shows a needle <NUM> of a phacoemulsification probe already inserted into a chamber <NUM> of the eye <NUM> through an incision <NUM>. The tube <NUM> of the ophthalmic curette device <NUM> is configured to be inserted through a second incision <NUM> into the chamber <NUM> of the eye <NUM>.

The tube <NUM> (which extends beyond the supporting member <NUM>) may have any suitable length, which is long enough for the tube <NUM> to be inserted into the eye <NUM> and be maneuvered during the medical procedure. In some embodiments, the tube <NUM> (which extends beyond the supporting member <NUM>) has a minimum length of <NUM>. The tube <NUM> may have any suitable outer diameter and wall thickness. In some embodiments, the tube <NUM> has an outer diameter between <NUM> and <NUM>, and a wall thickness between <NUM> and <NUM>.

Referring again to <FIG>. , in some embodiments, the ophthalmic curette device <NUM> includes a pressure sensor <NUM> disposed inside the tube <NUM> at the distal end <NUM> of the tube <NUM>. The pressure sensor <NUM> is configured to provide a signal responsively to intraocular pressure inside the chamber <NUM> (<FIG>) of the eye <NUM> (<FIG>). Any suitable pressure sensor, which is small enough to insert inside the tube <NUM>, and is sensitive enough to accurately measure the intraocular pressure, may be used. A suitable pressure sensor (e.g., P330B) is commercially available from Amphenol Thermometrics Inc. Mary's, PA <NUM>, United States. The P330B pressure sensor has high pressure sensitivity and has a size of <NUM> x <NUM> x <NUM> microns. The longest dimension of the P330B pressure sensor may be aligned parallel to the axis of the tube <NUM>.

In some embodiments, the ophthalmic curette device <NUM> includes a temperature sensor <NUM> disposed inside the tube <NUM> at the distal end <NUM> of the tube <NUM>. The temperature sensor <NUM> is configured to provide a signal responsively to a temperature inside the chamber <NUM> (<FIG>) of the eye <NUM> (<FIG>). Suitable miniature medical temperature sensors are commercially available from ATC Semitec Ltd, Anderton, Northwich, Cheshire, CW9 6FY, U.

In some embodiments, the ophthalmic curette device <NUM> includes the pressure sensor <NUM> and the temperature sensor <NUM>. The pressure sensor <NUM> and the temperature sensor <NUM> are described in more detail with reference to <FIG>.

In some embodiments, the ophthalmic curette device <NUM> includes a magnetic position sensor <NUM> disposed inside the tube <NUM>. The magnetic position sensor <NUM> may be configured to be used as part of a position tracking system (not shown) for tracking a position of the distal end <NUM> of the tube <NUM>. As the tube <NUM> is rigid, the magnetic position sensor <NUM> may be disposed at any suitable position inside the tube <NUM>. The magnetic position sensor <NUM> is described in more detail with reference to <FIG>.

The ophthalmic curette device <NUM> optionally includes a processor <NUM> and a display <NUM>. In some embodiments, the processor <NUM> is configured to compute a pressure value responsively to the signal provided by the pressure sensor <NUM>. In some embodiments, the processor <NUM> is configured to compute a temperature value responsively to the signal provided by the temperature sensor <NUM>. The display <NUM> is configured to render the pressure value and/or the temperature value.

The processor <NUM> and the display <NUM> may be disposed in/on the handle <NUM>. The display <NUM> may include any suitable display, for example, a liquid crystal display.

In some embodiments, a display <NUM> may also be disposed in a remote console <NUM>, which is connected with the handle <NUM> wirelessly and/or via wires <NUM>. The display <NUM> is configured to render the pressure value and/or the temperature value. The handle <NUM> and the console <NUM> may each include an interface <NUM> to provide data communication between the handle <NUM> and the console <NUM>. The interfaces <NUM> may comprise circuitry to allow wired and/or wireless communication therebetween.

In some embodiments, the display <NUM> may be disposed in the remote console <NUM> without a display on the handle <NUM>. In these embodiments, the processor <NUM> may be disposed in the handle <NUM> or the console <NUM>.

In practice, some or all of the functions of the processor <NUM> may be combined in a single physical component or, alternatively, implemented using multiple physical components. These physical components may comprise hard-wired or programmable devices, or a combination of the two. In some embodiments, at least some of the functions of the processor <NUM> may be carried out by a programmable processor under the control of suitable software. This software may be downloaded to a device in electronic form, over a network, for example. Alternatively, or additionally, the software may be stored in tangible, non-transitory computer-readable storage media, such as optical, magnetic, or electronic memory.

In other embodiments, the displays <NUM>, <NUM> and/or the processor <NUM> are not included in the handle <NUM> or the console <NUM>.

In some embodiments, the sensor signal(s) and/or computed temperature and/or pressure values are conveyed via wires and/or wirelessly to a remote processing device (not shown) which processes the sensor signals and/or uses the computed temperature and/or pressure values as part of a medical procedure process. For example, medical procedure parameters such as phacoemulsification probe needle vibration frequency, amplitude, and/or mode may be adjusted according to the temperature and/or pressure values.

Reference is now made to <FIG>, which is a cross-sectional view of the ophthalmic curette device <NUM> through line A:A of <FIG>.

The magnetic position sensor <NUM> may include at least one coil <NUM>. The magnetic position sensor <NUM> may be implemented as a single axis sensor (SAS) with one coil, as a dual axis sensor (DAS) with two orthogonally disposed coils, or a triple axis sensor (TAS) with three orthogonally disposed coils. Each coil may be a printed coil or a wound coil, e.g., wound on a suitable magnetic core. The ophthalmic curette device <NUM> may include a cable <NUM> connecting the magnetic position sensor <NUM> with the processor <NUM> (<FIG>) or the interface <NUM> (<FIG>) in the handle <NUM> (<FIG>).

Magnetic field generators may be placed at known locations external to the patient, for example, around the head of the patient or in a collar around the neck of the patient. The magnetic position sensor <NUM> generates electrical signals in response to these magnetic fields, which may be processed to determine a position (e.g., location and/or orientation) of the distal end <NUM> of the ophthalmic curette device <NUM>. Magnetic tracking system are described in <CIT>, <CIT>, <CIT>, <CIT>, <CIT> and <CIT>, in <CIT>, and in <CIT> and <CIT> and <CIT>. The magnetic position sensor <NUM> may allow the ophthalmic curette device <NUM> to be tracked during use, for example, during robotic guided surgery in which the ophthalmic curette device <NUM> may be robotically guided.

In some embodiments, the coil may include a magnetic core. For example, magnetic antennas can use a magnetic core made of a ferromagnetic or ferrimagnetic material such as iron or a nickel-zinc ferrite or magnesium-zinc ferrite to increase permeability. A magnetic core can increase the sensitivity of an antenna by a factor of up to several thousand, by increasing the magnetic field due to its higher magnetic permeability. Therefore, coils used in navigable probes typically include coils with a magnetic core. A solid magnetic core may be constructed by any suitable method including joining magnetic-core powder using a binder and/or very high temperatures (sintering) to form a solid mass. In some embodiments, the coil may include a magnetic core produced by one of the above methods. However, the above production methods are generally not suitable for producing solid magnetic cores which are small enough to insert into a coil having an inner diameter of about <NUM> microns or less.

Therefore, in some embodiments, a magnetic core may be formed from a tube containing separate powder granules of a ferrite. The tube may have any suitable inner diameter. The inner diameter of the tube may be in the range of <NUM> to <NUM> microns. A coil is then placed around the tube, for example, by inserting the tube into the coil. The coil may be covered with a covering keeping the coil in place and acting as a biocompatible cover, for example, but not limited to a plastic cover such as a plastic tube, or with a coating such an as enamel or epoxy paint, shrink sleeve, or metal cover. A metal cover may also provide shielding from high frequency electromagnetic interference. The wire (e.g., copper wire) used in the coil may have any suitable gauge, for example, but not limited to <NUM> gauge which is about <NUM> microns in diameter. The powder granules are held in place by the tube. The powder granules may be bound together using a binder material such as epoxy. The tube may be formed from any suitable material such as a wide-range of thermoplastics, e.g., polyimide, polyamide, polyethylene terephthalate (PET), fluorinated ethylene propylene (FEP), or polyvinyl chloride (PVC) or other materials such as an engineered ceramic, a carbon material, or a non-ferromagnetic metal. The tube provides a controlled outer diameter surface on which to slide the coil.

As the powder granules may have a size of about <NUM> microns, it may be difficult to place the powder granules into the tube. Therefore, in some embodiments, separate powder granules of a ferrite are introduced into the tube using the following method. The tube may be made of any suitable material which can be heat-shrunk, for example, but not limited to, a wide-range of thermoplastics, e.g., polyamide, polyethylene terephthalate (PET), fluorinated ethylene propylene (FEP), or polyvinyl chloride (PVC). While the powder granules are introduced into the tube, the tube typically has an outer diameter which is greater than an inner diameter of the coil. For example, if the inner diameter of the coil is <NUM> microns, the outer diameter of the tube in to which the powder granules are disposed has an outer diameter of <NUM> microns and an inner diameter of about <NUM> microns. The outer diameter of the tube shrinks to <NUM> microns after being heat shrunk. The preshrunk tube may have any suitable outer diameter in accordance with the inner diameter of the coil and the heat shrink properties of the plastic tube. The preshrunk tube may have any suitable outer diameter, for example, in the range of <NUM> - <NUM> microns. The powder granules may be bound together after being placed in the tube using a binder such as a low viscosity epoxy, which may be wicked in to the tube with capillary action after the tube is shrunk, or before the tube is shrunk and then the tube is shrunk while the epoxy is still liquid as it would not be possible to shrink the tube once the epoxy is cured. The powder granules may have any suitable size which is less than the inner diameter of the tube in to which the powder granules are disposed. The powder granules may be introduced into the tube using any suitable method. For example, the powder granules may be introduced into the tube with the aid of a funnel which is aligned with the tube opening. The funnel is filled with the powder granules and is vibrated up and down, and/or side-to-side, using any suitable vibration method, such as an ultrasonic method. The funnel may be connected with the tube, and vibrated in unison with the tube to facilitate the introduction of the powder granules into the tube. Additionally, or alternatively, one or more magnets (electromagnetics and/or permanent magnets) may be connected to the tube to facilitate introduction of the powder granules into the tube. For example, using a magnet connected to the bottom of the tube and/or a ring-type magnet connected around the tube. The magnet(s) may allow movement (up and down, and/or sideways movement), vibration (up and down, and/or sideways vibration), and/or rotation of the tube.

In some embodiments, the powder granules may be introduced into a tube without subsequently heat shrinking the tube. In these embodiments, the powder granules are suspended in a liquid, such as an alcohol, for example, but not limited to, isopropyl alcohol, or any other liquid which has a sufficiently low viscosity and a high enough evaporation rate. The suspending may be performed using any suitable method for example, but not limited to, placing the powder granules with the liquid in a container on a vibration table or by using any other vibration method, such as using ultrasound. The percentage of powder granules in the suspension, by volume, may be any suitable value, for example, in the range of <NUM>-<NUM>%. An end of an empty tube is placed in the liquid so that capillary action draws some of the liquid with the powder granules into the tube. The tube has an outer diameter less than the inner diameter of the coil, for example, in the range of <NUM> to <NUM> microns. The inner diameter of the tube is generally in the range of <NUM> to <NUM> microns. The tube may be made of any suitable material, for example, but not limited to, plastic, an engineered ceramic, a carbon material, or a non-ferromagnetic metal. Once the liquid-granule mixture is in the tube, the liquid is evaporated from the tube using any suitable method such as using heat and/or by blowing air over the tube. After the evaporation, a binder such as a low viscosity epoxy may be wicked into the tube with capillary action to bind the powder granules together.

The pressure sensor <NUM> may be disposed at the distal tip of the tube <NUM>. In some embodiments, the temperature sensor <NUM> may be disposed next to the pressure sensor <NUM> at the distal tip if there is enough room in the distal tip for both sensors <NUM>, <NUM>. The pressure sensor <NUM> and the temperature sensor <NUM> may be connected to the inner surface of the tube <NUM> using a suitable adhesive <NUM>, which also prevents liquid from reaching electrical connections, wires and the magnetic position sensor <NUM>.

If there is not enough room for both sensors <NUM>, <NUM> at the distal tip, the pressure sensor <NUM> is generally disposed at the distal tip and the temperature sensor <NUM> is disposed proximally to the pressure sensor <NUM>, or vice-versa. The magnetic position sensor <NUM> is generally, but not necessarily, disposed proximally to the pressure sensor <NUM> and the temperature sensor <NUM>.

The pressure sensor <NUM> and the temperature sensor <NUM> may be connected using wires/cables <NUM> to the processor <NUM> (<FIG>) and/or the interface <NUM> (<FIG>) in the handle <NUM> (<FIG>). In some embodiments, the wires/cables <NUM> may extend out of the handle <NUM> for connection to the remote console <NUM> (<FIG>).

Reference is now made to <FIG> and <FIG>, which are views of the distal end <NUM> of the ophthalmic curette device <NUM> of <FIG>. <FIG> shows that the distal end <NUM> has a smooth or rounded edge <NUM>. <FIG> shows the pressure sensor <NUM> disposed in the distal end <NUM> of the tube <NUM>. The temperature sensor <NUM> and the magnetic position sensor <NUM> are not shown in <FIG> and <FIG> for the sake of simplicity.

Reference is now made to <FIG>, which is a cutaway view of the distal end of the ophthalmic curette device <NUM> of <FIG>. <FIG> shows the cables <NUM> extending from the pressure sensor <NUM> down the inside of the tube <NUM> towards the handle <NUM> (<FIG>). <FIG> also illustrates the supporting member <NUM> surrounding the proximal portion of the tube <NUM>. The temperature sensor <NUM>, the magnetic position sensor <NUM>, and their associated wires/cables are not shown in <FIG> for the sake of simplicity.

Reference is now made to <FIG>, which is a schematic view of a distal end of an ophthalmic curette device <NUM> constructed and operative in accordance with an alternative embodiment of the present invention. The ophthalmic curette device <NUM> is substantially the same as the ophthalmic curette device <NUM> except that the ophthalmic curette device <NUM> includes a loop <NUM> or hook connected to the distal end <NUM> of the tube <NUM>. The width of the loop is typically about the size of the outer diameter of the tube <NUM>. The length of the loop <NUM> extending away from the distal end <NUM> may have any suitable size, for example, between half and twice the size of the outer diameter of the tube <NUM>.

Various features of the invention which are, for clarity, described in the contexts of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment may also be provided separately or in any suitable sub-combination.

Claim 1:
An ophthalmic curette device (<NUM>), comprising:
a handle (<NUM>) having a distal end;
a tube (<NUM>) having a proximal end (<NUM>) connected to the distal end of the handle, and having a distal end (<NUM>), and configured to be inserted through an incision into an eye;
characterized in the device comprises
a magnetic position sensor (<NUM>) disposed inside the tube; and further comprises one or both of:
a pressure sensor (<NUM>) disposed inside the tube at the distal end of the tube, and configured to provide a signal responsively to intraocular pressure inside the eye; and
a temperature sensor (<NUM>) disposed inside the tube at the distal end of the tube and configured to provide a signal responsively to a temperature inside the eye.