Patent Publication Number: US-2021186756-A1

Title: Surgical instruments for ocular surgery

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 62/702,775, filed Jul. 24, 2018, which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE DISCLOSURE 
     The disclosure relates to medical instruments, and more specifically, to surgical instruments for performing ocular surgery. 
     BACKGROUND 
     A cataract is a type of visual impairment, and is defined as an opacity in the crystalline lens of the eye, which interferes with vision. Once visual function has been compromised by a cataract, surgery is performed to remove the opaque lens in order to restore proper eye function. Cataracts are the most prevalent disabling eye disease worldwide. 
     Many methods of cataract extraction have been developed. Some of these methods require large incisions that are unstable and require prolonged recovery times. More current techniques generally require making much smaller incisions in the eye, and removing the cataract from the eye through this small incision. Smaller incisions, of course, result in more rapid post-operative recovery and a more structurally stable eye. Thus, the presently preferred surgical method of cataract extraction is extracapsular removal, such as by extracapsular surgery or phacoemulsification, through a very small incision. 
     More specifically, surgeries today typically involve making a very small incision (2-7 mm) in the eye, and either removing the cataractous nucleus intact or emulsifying/fragmenting the nucleus and mechanically removing the pieces through the incision. As referenced above, smaller incision sizes are preferably, although the smaller the incision the greater the fragmentation of the cataract that is required to remove it from the eye. 
     Yet more particularly, phacoemulsification typically utilizes ultrasonic energy to emulsify a cataract nucleus and aspirates the cataract from the eye through the aforementioned small incision. Of note, the advent of foldable intraocular lenses to complete this surgery has resulted in sutureless surgery of even the referenced small incision with virtually immediate visual and functional recovery. For these and other reasons, phacoemulsification has become the most practiced method of cataract surgery. Nevertheless, phacoemulsification is very expensive, and requires expensive and sophisticated equipment that demands significant expertise to operate safely. 
     Further, ultrasonic phacoemulsification can suffer impediments to optimal performance. For example, cavitation bubbles which result from ultrasonic activity in a liquid may adversely impact phacoemulsification results. Corneal burns can also occur due to the friction of the phacoemulsification tip and the eye incision, which friction results from the ultrasonic vibration of the phacoemulsification tip. That is, corneal burns may result from the maintaining of contact between the emulsifying instrument as it vibrates and the cornea. Corneal burn is the highest occurrence of adverse clinical impact to the patient in intraocular surgery. 
     As such, the use of a non-ultrasonic handpiece, if a small incision size could be maintained, might eliminate some known adverse impacts on surgical performance, and hence may improve ocular surgical outcomes. Moving to a non-ultrasonic handpiece may additionally simplify the required surgical console and console driver, thereby lowering the required expertise and experience to perform ocular surgery, which additionally would decrease the cost of surgery. 
     Some non-ultrasonic ocular surgical instruments that have been utilized in removing cataractous nucleii include screw-like distal cutting elements, which generally consist of a small bore rotating cutting element that is maintained in continuous physical contact with the cataract. However, because such methods typically lack an ability to maintain position, and lack the aspiration and irrigation elements typical in phacoemulsification, maintenance of continued contact between the cutting element and cataract becomes very difficult, and fragments of the cataract are overly free to float about inside the eye in a variably pressurized environment, thereby complicating cataract removal and increasing the likelihood of damage. Thus, to the extent vacuum control is minimal in such embodiments, a “catch basket” is included to catch fragments of the cataract as the cutting element operates. To the extent pressure differential vacuum control is included in such embodiments to aid in the removal of macerated tissue and aid in stabilizing the cataract, the arrangement often results in inelegant communication between the screw, the aspiration system and any irrigation system, particularly if particles become stuck in the aspiration system. 
     The condition wherein a particle gets stuck, or “occludes”, the aspiration during phacoemulsification can cause either sudden increases or drops in eye pressure, or significant fluid flow with concomitant turbulence inside the eye, which instances have great potential for intraocular damage. One such condition, referred to as post-occlusion surge (POS), is a well-known phenomenon in ocular surgery. During normal surgical conditions (i.e., when the phacoemulsification tip is not occluded), the vacuum level of the aspirator is relatively low. However, in a POS condition, occlusion at the emulsifying tip of the handpiece allows the aspirating vacuum to build (such as to a preset vacuum shutoff limit) until the blockage is broken. Upon breaking of the occlusion, stored energy in the tubing causes a rapid surge flow from the patient&#39;s eye, which can cause adverse effects to the structures within the eye. While mini-surges may happen hundreds of times during a typical phacoemulsification surgery, a major POS event may only happen occasionally, but with very significant adverse effects to the patient. By way of non-limiting example, the posterior capsule of the eye may be torn upon a POS. 
     For at least the foregoing reasons, there is a need for simpler and less expensive systems, apparatuses, and methods for performing cataract surgery. Such an apparatus, system and method would provide a surgical instrument for safe, controlled, and uncomplicated removal of a cataractous nucleus from the eye in its entirety, regardless of the maturity or hardness of the nucleus, while using a small eye incision size and with minimized risk of aspiration blockage-induced damage. 
     SUMMARY OF THE DISCLOSURE 
     The disclosure includes at least an apparatus, system and method for a handpiece for ocular surgical. The foregoing may include a handle having at least inlets for irrigation and aspiration; a sleeve extending distally from a first end of the handle, wherein the sleeve comprises a bore extending a length of the sleeve along a central axis of the sleeve, and comprises at least one port suitable to deliver the irrigation from the irrigation inlet substantially distally from the first end of the handle; the aspiration being provided at a bore port distal to the first end via fluidic communication between the aspiration inlet and the distal bore port; a motor coupled with a second end of the handle opposite the first end and having a motor shaft; and an auger associated with the motor shaft, and extending at least partially through an interior portion of the handle between the second end and the first end and extending along the length of the sleeve, wherein a tip of the auger distal to the motor shaft is advanced by actuation of the motor to emulsify an eye lens. 
     The apparatus, system and method may also include a handpiece for ocular surgery that provides interchangeable emulsification, which may include at least a hollowed handpiece body comprising a handle and a sleeve extending from the handle; irrigation and aspiration outputs at an operative end of the sleeve opposite the handle; and an interchangeable emulsifying assembly. The emulsifying assembly may include a motor; a motor mount suitable to receive the motor and interchangeably mount the motor to the handle opposite the sleeve; and an auger suitable for interchangeable operative connection to the motor, wherein the auger extends axially through the hollow and outwardly from the operative end. 
     Thus, the disclosure may provide simpler and less expensive systems, apparatuses, and methods for performing cataract surgery. The apparatus, system and method may provide a surgical instrument for safe, controlled, and uncomplicated removal of the cataractous nucleus from the eye in its entirety, regardless of the maturity or hardness of the nucleus, while using a small eye incision size and with minimized risk of aspiration blockage-induced damage. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated into and thus constitute a part of this specification. The drawings illustrate disclosed embodiments and/or aspects and, together with the description, serve to explain the principles of the disclosure. In the drawings: 
         FIG. 1  is a cross-sectional view of an eye subjected to phacoemulsification surgery; 
         FIGS. 2A and 2B  are illustrative views of an exemplary ocular surgical instrument; 
         FIG. 3  is an illustrative view of an exemplary ocular surgical instrument; and 
         FIG. 4  is an illustrative view of an exemplary ocular surgical instrument. 
     
    
    
     DETAILED DESCRIPTION 
     The figures and descriptions provided herein may be simplified to illustrate aspects of the described embodiments that are relevant for a clear understanding of the herein disclosed processes, machines, manufactures, and/or compositions of matter, while eliminating for the purpose of clarity other aspects that may be found in typical surgical, and particularly ophthalmic surgical, devices, systems, and methods. Those of ordinary skill may thus recognize that other elements and/or steps may be desirable or necessary to implement the devices, systems, and methods described herein. Because such elements and steps are well known in the art, and because they do not facilitate a better understanding of the disclosed embodiments, a discussion of such elements and steps may not be provided herein. However, the present disclosure is deemed to inherently include all such elements, variations, and modifications to the described aspects that would be known to those of ordinary skill in the pertinent art. 
     Embodiments are provided throughout so that this disclosure is sufficiently thorough and fully conveys the scope of the disclosed embodiments to those who are skilled in the art. Numerous specific details are set forth, such as examples of specific aspects, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. Nevertheless, it will be apparent to those skilled in the art that certain specific disclosed details need not be employed, and that embodiments may be embodied in different forms. As such, the exemplary embodiments set forth should not be construed to limit the scope of the disclosure. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. For example, as used herein, the singular forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The steps, processes, and operations described herein are not to be construed as necessarily requiring their respective performance in the particular order discussed or illustrated, unless specifically identified as a preferred or required order of performance. It is also to be understood that additional or alternative steps may be employed, in place of or in conjunction with the disclosed aspects. 
     When an element or layer is referred to as being “on”, “upon”, “connected to” or “coupled to” another element or layer, it may be directly on, upon, connected or coupled to the other element or layer, or intervening elements or layers may be present, unless clearly indicated otherwise. In contrast, when an element or layer is referred to as being “directly on,” “directly upon”, “directly connected to” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). Further, as used herein the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Yet further, although the terms first, second, third, etc. may be used herein to describe various elements or aspects, these elements or aspects should not be limited by these terms. These terms may be only used to distinguish one element or aspect from another. Thus, terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the disclosure. 
     Embodiments provide simpler and less expensive systems, apparatuses, and methods for performing cataract surgery. The apparatus, system and method provide a surgical instrument for safe, controlled, and uncomplicated removal of a cataractous nucleus from the eye in its entirety, regardless of the maturity or hardness of the nucleus, while using a small eye incision size and with minimized risk of aspiration blockage-induced damage. 
     With reference to  FIG. 1 , a cornea  20  of a human eye  10  is illustrated. The cornea  20  is a generally arcuate segment in front of the iris  22 . The region between the iris and the cornea  20  is known as the anterior chamber of the eye. Directly behind the iris  22  is a lens capsule  24 , and, in a healthy eye, a natural crystalline convex lens  25  is housed within the capsule  24  for focusing light, in cooperation with the cornea  20 , upon the retina. 
     Through trauma, age or other causes, the natural crystalline lens  25  may become cloudy and fail to transmit and focus light in a proper manner. When this condition exists, a patient is said to have a “cataract,” and the patient may become progressively functionally blind in the eye suffering from the cataract. Cataracts are a leading cause of blindness throughout the world, but a cataractous lens may be removed and replaced with an artificial intraocular lens to at least partially restore sight. 
     A currently preferred technique for removing a cataract lens is known as phacoemulsification, and this technique employs irrigation and aspiration in conjunction with ultrasound for emulsification of the affected lens  25 . In phacoemulsification, an incision or opening  26  is surgically fashioned through the limbus portion of the eye. This opening serves to admit the tip of a phacoemulsification handpiece  12 . The operative end  28  of the handpiece is operably extended through the cornea and into juxtaposition with lens  25 . 
     In a conventional phacoemulsification, phacoemulsification handpiece, an electromagnetic core  32  internal to the handpiece  12  is ultrasonically excited from a power source. The core rapidly vibrates at between 10,000 and 100,000 cycles per second, for example. This rapid ultrasonic vibration serves to vibrate a tip  34  of the handpiece, which is brought into physical contact with the cataractous lens  25 . The rapidly vibrating tip  34  physically emulsifies the cataract. 
     Concomitantly, an irrigation fluid  36  is supplied by the handpiece to commingle with and operably suspend bits of the emulsified cataract within, and further to maintain an acceptable pressure within, the anterior chamber. A vacuum  38  is also drawn by the handpiece, which serves to pull the irrigating fluid and suspended cataract material co-axially through the tip  34  and back to a collection reservoir. 
     In the embodiments of the present invention a phacoemulsification handpiece may employ a rotary motor and auger to perform emulsification of the eye lens, rather than employing the ultrasonic vibrating tip typically used to emulsify a cataractous lens in the known art. More specifically, in embodiments, the handpiece may include, passing substantially through a center axis thereof, an internal rotating rod acting as the emulsifying auger. 
     In embodiments, the internal auger may pass within an irrigating sleeve, wherein the irrigating sleeve may have one or more ports through which fluid may flow. For example, the auger may pass through a bore axially down the center of the irrigating sleeve, and the bore may also provide, such as therewithin or via a passageway through the auger, aspiration for removal of the lens emulsified by the auger. As such, embodiments may provide a handpiece, such as may include a handle having inputs/outputs to the sleeve ports and a sleeve having a center bore therethrough, formed of various materials, such as titanium or plastics. 
     The irrigation sleeve provided in the embodiments may not be subjected to ultrasonic vibration, as would be the case in the known art. Areas of the disclosed irrigation sleeve may be pre-shaped in something other than the known straight edged cylinder in the known art. For example, the sleeve may instead be pre-shaped to a variable thickness so to minimize wound leakage at the point of entry of the sleeve through the eye incision once the tip of the sleeve is within the subject eye. 
     As is illustrated in  FIG. 2A , embodiments may include a handpiece  100  having a handle  102  physically associated with an outer sleeve  104 . In the illustration, the hand piece  100  may be fixed, i.e., may be non-vibrating, thereby providing refined positional access to a cataractous lens. The hand piece  100  may include, such as passing through the handle thereof, one or more inlets and outlets  108 , such as may be associated with the providing of irrigation to a port at or near the tip of the outer sleeve where the emulsification may occur, and/or aspiration to the tip of and/or otherwise from the bore  110  of the outer sleeve  104 . 
     In the illustration, irrigation may outflow from one or more ports  112  on sleeve  104  as illustrated, such as via fluidic communication between ports  112  and the one or more inlets and outlets  108  shown as passing through the handle  102 . Irrigation may flow along one or more paths, such as outer bore  111 , outside of central bore  110 , as shown in  FIG. 2B . Other fluidics, such as including the aspiration for the cataractous lens, may also flow through or along the central bore  110  of the sleeve  104 . Thereby, particles of the lens, such as including the cataract, may, during and after emulsification, be irrigated by the irrigation and aspirated via the center bore  110  of the outer sleeve  104 . For example, maintenance of the requisite eye pressure for the emulsification may be enabled by irrigation that is provided via ports  112  in sleeve  104 , while the aspiration port balances the irrigation fluid with the provided vacuum. 
     With reference now also to  FIG. 3  and in accordance with the foregoing, should an occlusion of the aspiration occur, such as because of a particle stuck at or near the tip  104   a  of the outer sleeve  104 , the illustrated handpiece  100  may energize, or further energize, the rotating auger  120  passing through the center axis of the bore  110  of the outer sleeve  104 . This energizing may be based on actuation of a rotary motor  130  operationally associated with a distal portion  120   b  of the auger  120 , and may thereby fragment the occlusion. Accordingly, the occlusion may be continuously released by the rotation of the auger  120 , rather than being suddenly sucked into clogging the aspirator as would be the case in the known art. As such, the disclosed solution better remedies the occlusion, as the removal of the occlusion may be dependent upon the rotation of the auger  120 , rather than on the vibration of the handpiece tip and heightened use of the vacuum to remove the occlusion as would be the case in the known art. Of course, as will be understood to the skilled artisan in light of the discussion herein, a pitch of the auger  120  may be varied in order to best fragment the material of the cataractous lens to a preferred size, such as to thereby largely prevent occlusion of the aspiration line as compared to the known art. 
     The association of the outer sleeve  104 , handle  102 , and inlets and outlets  108  of  FIG. 2  with an internal auger  120 , an operating rotary motor  130 , and mechanical link/protective o-ring  132  is illustrated, by way of example, in  FIG. 3 . More particularly, rotary motor  130  may be employed in order to rotate the auger  120  that passes through central bore  110  of the outer sleeve  104 , as discussed throughout. The rotation of the auger  120  causes the auger to distally “advance” through the cataractous lens. 
     In an embodiment, outer sleeve  104  and/or a portion of handle  102  may be at least partially surrounded by a second outer sleeve (not shown). In this embodiment, outer sleeve  104  does not have the one or more ports  112 , but rather the second outer sleeve may have one or more ports for the irrigation fluid to exit at the distal end of the second outer sleeve and have one or more corresponding fluid pathways along the central access of the outer sleeve  104  to direct the irrigation fluid out of the distal end. The second outer sleeve may be of any material known in the art, including a soft pliable polymer, e.g. silicone, or may be a metal material, e.g. titanium. The second outer sleeve may cover the distal end of outer sleeve  104  or at least a portion of the distal end of outer sleeve  104 . 
     It is understood that the force required to bisect a cataractous lens varies with a number of factors, including the age of the patient, the extent of the cataract, the hardness of the lens, and various other factors. However, this force is generally in the range of about 0.25 to 2.25 Newtons of force, and may more particularly fall within a range of 0.5 to 1.7 Newtons of force, by way of non-limiting example. As this level of force would accordingly be required of the auger  120  in order to fragment the cataractus lens, the choice of motor  130  should be made in order to deliver the requisite force for a particular lens to be emulsified. As such, a motor  130  providing force to the auger  120  at the upper end of the aforementioned range(s) may work for all cataractous lenses, although such motors may be more expensive. Thus, various different motors  130  to rotate the referenced auger  120  may be selectable, such as based upon the power needed in accordance with the patient-centric factors discussed above. 
     Some embodiments may thus be modular, such as wherein various aspects, such as the outer sleeve  104  and/or the rotating auger  120  and/or the motor  130  may be variably and/or selectably associated with the handpiece, i.e., may be variably associated with the handle body  102 . Thereby, aspects of the embodiments may provide interchangeable and/or disposable handpieces  100 , either in part or in total. Further, variably autoclavable motors, based upon varying aspiration embodiments, may also be employed in the embodiments. 
     Further, the irrigation and aspiration inlets/outlets  108  and ports  112  may be located anywhere along the outer portion of the hand piece handle  102  and/or sleeve  104 . This is because, at least in part, the outer sleeve  104  and handle  102  may merely provide a “shell” for the irrigation and aspiration fluidics supplied in conjunction with the auger  120 . As will be understood in light of this shell functionality, the outer sleeve  104  may be built into and/or otherwise rigid in relation to the handle  102 , at least because no vibration of the outer sleeve is necessary as it would be in the known art. Alternatively, sleeve  104  may be a wholly separate physical element from the handle  102 . 
     More particularly, and as is evident from the example of  FIG. 3 , the lens material and/or fluid may flow from the distal end of sleeve  104  through the bore  110  to its respective inlet  108 , and may thus be bounded by the auger  120  and the inner wall of the outer sleeve  104  or in another embodiment, a lumen created within the sleeve  104  may either surround the auger or run along the side of auger  120  within sleeve  104 . Of note, the auger tip  120   a  may have a graduated pitch in order to ensure that particles are reduced to or below a certain size, such as to prevent occlusion of the aspiration via particles getting stuck between the inner wall of the bore opening  110  and the auger  120 . 
     The opposing end  120   b  of the auger  120  may be operationally associated with a rotating motor shaft  130   a  of motor  130 , as discussed throughout. The motor shaft  130   a  may, needless to say, thus serve to rotate the auger  120  at a rate correspondent to the force and speed of motor  130 . The motor  130  may be physically associated with the handle  102  via a motor mounting  132 , such as the o-ring assembly illustrated in  FIG. 3 . 
     The motor mounting  132  may be securely, detachably or non-detachably, physically associated with a hollowed distal portion of the handle  102 , such as wherein the motor mount  132  and inner wall of the end of the handle  102  are matably threaded, such that the motor  130  may be screwed into the handle  102  by mating of the motor mount threads to the receiving threads of the handle, and hence so that the auger  120  associated with the shaft  130   a  of motor  130  passes through the bore  110  axially through the outer sleeve  104 . A plastic or rubberized o-ring may or may not be associated with an o-ring groove of the motor mount  132 , such that the motor  130 , motor shaft  130   a  and auger  120  may be sealed to the hand piece  120  in order to avoid fluidic leakage from the handpiece  100 . 
     As discussed throughout, any of a variety of motors  130  sufficient to provide the requisite force for a given cataractous lens may be employed in the embodiments. The selected motor  130  should provide sufficient torque so as to turn the auger  120  at an acceptable rate when pulling cataract material into the proximal tip  104   a  of the outer sleeve  104 . Accordingly, a motor  130  of any size to provide the requisite torque may be employed in the embodiments, although certain motors, such as an 8 mm diameter by 22 mm long motor, may result in shorter and thinner handpieces  100  for phacoemulsification than are provided in the known art. 
     A motor  130  and auger  120  assembly  400  is illustrated in the embodiment of  FIG. 4 . In the illustration, it will be understood that the auger  120  may be detachably associated with the motor shaft  130   a , or may be permanently affixed to the motor shaft  130   a . Further, it will be understood that the auger  120 , o-ring/mounting assembly  132 , and/or motor  130  may be used disposably or nondisposably, such as based upon the use-case. Moreover, it will be appreciated, to the extent augers  120  are changeably associated with motors  130 , that any of a variety of augers  120 , and/or any of a variety of motors  130 , may be variably employed in phacoemulsification, such as based on patient characteristics and/or characteristics of the cataractous lens, by way of non-limiting example. 
     It will be appreciated that a combination phacoemulsification and irrigation/aspiration hand piece  100  may be provided in the embodiments. Additional and alternative aspects to those discussed throughout may also be provided. Of note, an insert (not shown) may be provided to extend beyond the external portion of the outer sleeve. This insert may have soft silicon protrusions, for example, which may be used to engage in a manual scrub. Additionally, the insert may interlock with the auger discussed throughout, such as via any known methodology, to thereby use the disclosed hand piece to spin the silicon protrusions. 
     Although the invention has been described and illustrated in exemplary forms with a certain degree of particularity, it is noted that the description and illustrations have been made by way of example only. Numerous changes in the details of construction, combination, and arrangement of parts and steps may be made. Accordingly, such changes are intended to be included within the scope of the disclosure.