The present disclosure relates to ophthalmic surgery, and more specifically, to an electronically actuated reciprocating surgical instrument.
Ophthalmic surgery is performed on the eye to save and improve the vision of tens of thousands of patients every year. However, given the sensitivity of vision to even small changes in the eye and the minute and delicate nature of many eye structures, ophthalmic surgery is difficult to perform and the reduction of even minor or uncommon surgical errors or modest improvements in precision or accuracy of surgical techniques can make a significant difference in the patient's vision after the surgery.
Ophthalmic surgical procedures are performed on an eye. Vitreoretinal surgical procedures are a class of ophthalmic surgical procedures that encompasses various delicate procedures involving internal portions of the eye, such as a vitreous humor and the retina. Vitreoretinal surgical procedures are performed, sometimes with lasers, to improve visual sensory performance. Vitreoretinal surgical procedures may be performed in the treatment of many eye diseases, including epimacular membranes; diabetic retinopathy; vitreous hemorrhage; macular hole; detached retina; complications of cataract surgery; or other eye diseases.
During vitreoretinal surgery, an ophthalmologist typically uses a surgical microscope to view a fundus through a cornea, while surgical instruments that penetrate a sclera may be introduced to perform any of a variety of different procedures. A surgical microscope provides imaging and optionally illumination of the fundus during vitreoretinal surgery. A patient typically lies supine under a surgical microscope during vitreoretinal surgery and a speculum is used to keep an eye exposed.
Modern ophthalmic surgery, such as vitreoretinal surgery, is typically performed with complex equipment, such as specialized surgical instruments; infusion pumps; pneumatic valves; pneumatic pumps; pneumatic compressors; aspirators; illumination sources; cooling fans; lasers; or other types of complex equipment. An example surgical instrument used in vitreoretinal surgeries is a handheld vitrectomy probe. In some instances, a vitrectomy probe is a reciprocating surgical instrument that uses dual pneumatic actuation inputs to control a duty-cycle of a reciprocating cutter.
According to one aspect, the disclosure is directed to a reciprocating surgical instrument for use in ophthalmic surgery that includes a housing body; a cutter extending from a distal end of the housing body, the cutter comprising a moveable cutter element; and a magnetic drive unit disposed in the housing body, the magnetic drive unit. The magnetic drive unit may include a permanent magnet and at least one electromagnetic coil. One of the permanent magnet and the electromagnetic coil may be fixed to the housing body of the reciprocating surgical instrument, and the other of the permanent magnet and the electromagnetic coils may be fixed to the moveable cutter element. The magnetic drive unit is operable to reciprocate the moveable cutter element.
Another aspect of the disclosure is directed to a method for operating a reciprocating surgical instrument for use in ophthalmic surgery. The method may include energizing an electromagnetic coil of a magnetic drive element disposed in a housing body of the reciprocating surgical instrument in an alternating manner; displacing a magnet of the magnetic drive element relative to the electromagnetic coil in response to the energized electromagnetic coil, one of the electromagnetic coil and the magnet fixed to a movable cutter element and the other of the electromagnetic coil and the magnet fixed to the housing body; and reciprocating the inner cutter element in response to the energizing the electromagnetic coil in the alternating manner.
The various aspects may include one or more of the following features. The moveable cutter element may be fixed to the permanent magnet, and the electromagnetic coil may be fixed to the housing body. The moveable cutter element may be fixed to the electromagnetic coil and the permanent magnet is fixed to the housing body. The housing body may form a handle sized and shaped to be held in a hand of a user. The magnetic drive unit may be operable to reciprocate the moveable cutter element at a rate of up to 1,000 cycles per second. The magnetic drive unit may include a voice coil actuator. Electrical power may be supplied to the at least one electromagnetic coil from an external power source. Electrical power may be supplied to the at least one electromagnetic coil from a battery disposed in the housing body. The cutter may also include an outer cutter element, and the inner cutter element may be reciprocable within the outer cutter element.
The various aspects may also include one or more of the following features. The reciprocating surgical instrument may be a handheld surgical instrument. The reciprocating surgical instrument may be a vitrectomy probe. Reciprocating the inner cutter element in response to the energizing the electromagnetic coil in the alternating manner may include reciprocating the moveable cutter element at a rate of up to 1,000 cycles per second. The magnetic drive unit may include a voice coil actuator. Electrical power for energizing the electromagnetic coil may be supplied from an external power source. The electrical power for energizing the electromagnetic coil may be supplied from a battery disposed within the housing body. The cutter element may be a multi-cutter element.
The details of one or more implementations of the present disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.
For a more complete understanding of the present disclosure and the associated features and advantages described herein, reference is now made to the following description, taken in conjunction with the accompanying drawings, which may not be drawn to scale and in which like numerals refer to like features.
For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the implementations illustrated in the drawings, and specific language will be used to describe the same. 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. In particular, it is fully contemplated that the features, components, and/or steps described with respect to one implementation may be combined with the features, components, and/or steps described with respect to other implementations of the present disclosure.
Throughout this disclosure, a hyphenated form of a reference numeral refers to a specific instance of an element and the un-hyphenated form of the reference numeral refers to the element generically or collectively. Thus, as an example (not shown in the drawings), device “12-1” refers to an instance of a device class, which may be referred to collectively as devices “12” and any one of which may be referred to generically as a device “12”. In the figures and the description, like numerals are intended to represent like elements.
A reciprocating surgical instrument may be a handheld surgical instrument that operates at relatively high cutting rates. For example, ULTRAVIT® vitrectomy probes produced by Alcon Laboratories, Inc., located at 6100-2 South Freeway, Fort Worth, Tex. 76134, are used during ophthalmic surgery for highly delicate and precise manipulations a surgeon. Vitrectomy probes typically include a cutter. The cutter includes a hollow outer cutter element, and a hollow inner cutter element arranged coaxially with each other. The inner cutter element moves within the outer cutter element in a reciprocating manner. The outer cutter element includes a cutting interface at a port. The port extends radially through the outer cutter element near a distal end thereof. Tissue is drawn into the port in response to an underpressure (referred to hereinafter as a vacuum) generated in the inner cutter element, and, when the inner cutter element is actuated to move distally towards the port, a cutting surface formed on the distal end of the inner cutter element, in cooperation with the cutting interface of the port, severs the tissue as the port closes. The tissue is then aspirated away through the inner cutter element. Tissue and other biological material that the vitrectomy probe removes, such as vitreous humor and retinal membranes, can vary in size.
Pneumatic actuation has been used to drive reciprocating surgical instruments. In the case of a single action pneumatic instrument, pneumatic pressure is utilized to displace the inner cutter element in a first direction, while a mechanical return mechanism, such as a mechanical spring, returns the inner cutter element in a second direction, opposite the first direction, thereby generating a reciprocating cutting action. In the case of a dual action pneumatic instrument, pneumatic pressure is utilized to actuate an inner cutter element in opposing first and second direction. However, pneumatically actuated surgical instruments may not have positional control of an actuated component.
The reciprocating surgical instruments disclosed herein contain an electronically actuated reciprocating component, such as, for example, a reciprocating vitrectomy cutter. The reciprocating surgical instruments disclosed herein may include a magnet-coil actuation system, such as a voice coil actuator (VCA), that is operable to reciprocate the reciprocating surgical instrument. These electronically actuated reciprocating surgical instruments include a microsurgical cutting probe for posterior segment ophthalmic surgery, during which a surgeon can control the port size as desired. The size of the instrument's port may be adjusted to maximize cutting efficiency and tissue stability. The electronically actuated reciprocating surgical instruments disclosed herein may operate without external pneumatic actuators and compressors, which may provide greater simplicity and fewer sources of ambient acoustical noise in an operating room environment.
For example, in some instances, the surgical instrument 100 may be a vitrectomy probe. The surgeon 120 uses the surgical instrument 100 to remove the clear, gel-like vitreous humor (“vitreous”) that normally fills the posterior segment of the eye 104. The surgeon removes vitreous while avoiding interaction with nearby eye structures, such as the retina, that are extremely sensitive to physical contact. The surgeon 120 may attempt to remove the vitreous from the eye 104 as quickly as possible in order to limit exposure of the retina to the light used to visualize the vitreous and, thereby, reduce potential injury to the retina that may result from excessive light levels. Surgical operations associated with the use of the surgical instrument 100 may involve sub-millimeter precision corresponding to fine biostructures in an eye, resulting in very small dimensional tolerances under which surgical instrument 100 operates.
As shown in
In contrast to a pneumatically driven surgical instrument, electronic actuation of the surgical instrument 100 provides the ability to positionally control (i.e., control the position of and, particularly, the fully retracted position of) the reciprocating component of the surgical instrument 100. In the instance where the surgical instrument 100 is a vitrectomy probe, the electronically actuated reciprocating component may be a cutting element. For example, in the context of a vitrectomy probe, a proximal-most position of an inner cutter element along a longitudinal axis of the vitrectomy probe may be selected and controlled during actuation of inner cutter element in order to vary the opening size of the cutter port. With the ability to vary the opening size of the cutter port, a region of space proximate to the cutter port on which a vacuum applied through the cutter port influences surrounding material (i.e., a region of influence) may be altered. For example, with a decreased port size, the region of influence is also decreased. With an increased port size, the region of influence similarly increases, as shown, for example, in
The surgical instrument 100 contains a magnetic drive unit that includes a permanent magnet and one or more electromagnetic coils (see also
As depicted in
As explained above, the surgical instrument 100-1 contains a magnetic drive unit 221 that includes a magnet 204 and two electrical coils 208 and 209. The housing 210 defines a chamber 207, and the magnetic drive unit is disposed in the chamber 207. The two electrical coils 208 and 209 are disposed on either side of the magnet 204. Particularly, a first electrical coil 208 is disposed proximally relative to the magnet 204, and a second electrical coil 209 is disposed distally relative to the magnet 204. In some implementations, such as the implementation illustrated in
The inner cutter element 202 reciprocates within the outer cutter element 212 in the directions of arrows 230 and 220 in response to actuation of the magnetic drive unit 221. The inner cutter element 202 includes a distal tip, which, for example, may be circular in cross-section. The distal tip is configured to cooperate with the port 214 to sever material extending through the port 214. Particularly, the distal tip of the inner cutter element 202 may cooperate with a distal edge of the port 214 to sever material extending through the port 214. In some instances, a port may be formed in the distal end of the inner cutter element 202 such that the cutter 201 performs two cuts per cycle of the inner cutter 202. Movement of the inner cutter element 202 in the direction of arrow 230 causes the distal tip thereof to move across the port 214. When the inner cutter element 202 has fully extended in the direction of arrow 230, the port 214 is in a closed condition. During this motion of the inner cutter element 202, any material extending into the port 214, such as, for example, vitreous, is cut. Movement of the inner cutter element 202 in the direction of arrow 220 retracts the inner cutter element 202, placing the port 214 in an open condition.
In some implementations, the magnetic drive unit 221 may include one or more position sensors. As shown in
The one or more position sensors are used to controlling a position of the inner cutter element 202. For example, the position sensors may be used to control where the distal tip of the inner cutter element 202 is positioned relative to the port 214 when extension or retraction of the inner cutter element 202 is stopped. That is, the position sensors may be used to control a position of the distal tip of the inner cutter element 202 relative to the port 214 when the inner cutter element 202 is at an extended or retracted position. For example, in some instances, the position sensors may be used to place the inner cutter element 202 in a partially retracted position such that the distal tip thereof is located at a position between the proximal and distal edges of the port 214. Thus, in such instances, with the inner cutter element 202 in a partially retracted position, the inner cutter element 202 obstructs a proximal portion of the port 214 resulting in an opening of the port 214 is less than the full size of the port 214. A position of the inner cutter element 202 may be controlled to partially open the port 214 to any desired opening size, thereby enabling precisely controlled variation of the size of the port 214. Consequently, vitrectomy instruments within the scope of the present disclosure provide for varying the opening size of the port 214 during a surgical procedure, unlike conventional vitrectomy probes that include no such capability or functionality.
At the proximal end of the housing body 210, the connector 218 provides for a connection to an aspiration line. A vacuum applied to the aspiration line operates to transport material through a hollow channel 216 extending through the housing body 210 and in fluid communication with the inner passage formed in the inner cutter element 202 and the passage formed in the outer cutter element 212. Accordingly, the outer cutter element 212 is fluidically coupled to the inner cutter element 202, which is, in turn, fluidically coupled to the connector 218. Aspirated materials are conveyed along this combined passage and are removed from the surgical instrument 100-1. The aspirated materials are transported away through the aspiration line connected to the connector 218. In this manner, the tissue, material that is cut at the port 214, and other materials may be removed during operation of the surgical instrument 100-1. Furthermore, with ability to control the size of the port 214 in combination with the ability to control an amount of vacuum applied at the connector 218, the surgical instrument 100-1 enables precise control of removal of material within a region surrounding the port 214, i.e., the region of influence, illustrated in
Thus, as the inner cutter element 202 extends in the first direction 230, the port 214 is fully closed and the material that has been drawn through the port 214 and into the outer cutting element 212 is cut as the distal tip of the inner cutting element 202 slides across the port 214. In some implementations, an edge of the outer cutter element 212 that defines the port 214 may be sharpened so as to cooperate with the distal tip of the inner cutter element 202 to perform a cutting action.
In further implementations and as explained above, the inner cutting element 202 may include a second port, which is referred to herein as a “multi-cutter element”. As the inner cutting element 202 extends in the direction of arrow 230 across the port 214, the second port formed in the inner cutting element 202 may become aligned with the port 214, thereby enabling material to be drawn into the cutter 201 through the overlapping ports formed in the inner cutter element 202 and the outer cutter element 212. The ingested material is severed as the inner cutting element 202 retracts in the second direction arrow 220. In this manner, the surgical instrument 100-1 produces multiple cuts for each reciprocation of the inner cutter element 202.
During operation of the example magnetic drive unit 221 shown in
The magnetic drive unit 221 includes a voice coil actuator 222. The VCA 222 includes a magnet 206 housed in a magnet frame 204 such that the magnet 206 and the magnet frame 204 are fixed relative to the housing body 210 and do not move within the surgical instrument 100-1. In some instances, the magnetic frame 204 may be formed from a magnetically soft material that can be magnetized by the fixed magnet 206, such as a ferromagnetic material. However, the disclosure is not so limited. Rather, the magnet frame 204 may be formed from any suitable material. For example, the magnetic frame 204 may be formed from any suitable magnetic material. The VCA 222 also includes an electromagnetic coil 208. The electromagnetic coil 208 is fixed relative to the inner cutter element 202. In some instances, the electromagnetic coil 208 may be fixed directly or indirectly to the inner cutter element 202. The electromagnetic coil 208 interacts with the magnet 206 to cause the electromagnetic coil 208 and the inner cutter element 202 to reciprocate within the housing body 210 and relative to the outer cutter element 212. In some instances, the VCA 222 further contains one or more position sensors that provide positional feedback of the inner cutter element 202 (as shown, for example, in
The housing body 210 includes a connector 218. Similar to the connector 218 described above, aspiration tubing may be attached to the surgical instrument 100-2 at the connector 218. A vacuum may be applied to a hollow channel 216. The vacuum is operable cause materials to be aspirated from the eye. The power cable 110 supplies electrical power to the electromagnetic coil 208 to activate the VCA 222 and produce reciprocating motion of the inner cutter element 202. In some implementations, the power cable 110 may also carry a positional feedback signal from the VCA 222. As explained above in the context of the surgical instrument 100-1, the positional feedback signals may be provided to a controller. The controller may be a microprocessor having access to memory media storing instructions executable by the microprocessor and execute software instructions. As a result, the controller is operable to control a longitudinal position of the inner cutter element 202 relative to the inner cutter element 212. In some implementations, the two electrical lines in the power cable 110 may also be used to carry the positional feedback signal, such as using a modulation technique. In various implementations, the surgical instrument 100-2 may operate at reciprocation rates of up to 1,000 cycles per second. However, the scope of the disclosure is not so limited. Rather, in other implementations, a VCA may have other configurations and may operate at different ranges of reciprocation rates. For example, in some instances, the rate of reciprocation may be within the range of 300 to 500 cycles per second. Still further, the rate of reciprocation may be higher or lower than the indicated range.
In
In
In
In
The opening size 310 of port 214 shown in
Moreover, as is clear by the above-provided description, the region of influence may be controlled both by controlling a fully retracted position of the inner cutter element 202 (and, hence, a size of the opening 310 of the port 308) and by adjusting a vacuum pressure applied to the port 214.
As disclosed herein, a handheld reciprocating surgical instrument may be an electronically actuated reciprocating surgical instrument. The electronic actuation may be provided by a magnetic drive unit. The magnetic drive unit may be a voice coil actuator (VCA). The magnetic drive unit may include positional feedback to enable positional control of a cutter element. In this manner, port-based flow control may be used to more precisely enable surgeons to accomplish surgical objectives and to control a size of the region of influence on mobile tissue affected by the cutter, for example.
The above disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other implementations which fall within the true spirit and scope of the present disclosure. Thus, to the maximum extent allowed by law, the scope of the present disclosure is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description.
This application claims the benefit of U.S. Provisional Application No. 62/522,974, filed Jun. 21, 2017, the entire contents of which are incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62522974 | Jun 2017 | US |