Patent ID: 12239575

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known methods, procedures, components, modules, units and/or circuits have not been described in detail so as not to obscure the invention.

Although embodiments of the invention are not limited in this regard, discussions utilizing terms such as, for example, “processing,” “computing,” “calculating,” “determining,” “establishing”, “analyzing”, “checking”, or the like, may refer to operation(s) and/or process(es) of a computer, a computing platform, a computing system, or other electronic computing device, that manipulates and/or transforms data represented as physical (e.g., electronic) quantities within the computer's registers and/or memories into other data similarly represented as physical quantities within the computer's registers and/or memories or other information non-transitory storage medium (e.g., a memory) that may store instructions to perform operations and/or processes. Although embodiments of the invention are not limited in this regard, the terms “plurality” and “a plurality” as used herein may include, for example, “multiple” or “two or more”. The tennis “plurality” or “a plurality” may be used throughout the specification to describe two or more components, devices, elements, units, parameters, or the like. Unless explicitly stated, the method embodiments described herein are not constrained to a particular order or sequence. Additionally, some of the described method embodiments or elements thereof can occur or be performed simultaneously, at the same point in time, or concurrently. Unless otherwise indicated, use of the conjunction “or” as used herein is to be understood as inclusive (any or all of the stated options).

Embodiments of the present invention herein describe a surgical tool for shearing tissue at a target surgical site. The surgical tool may include a cannula assembly with a distal end and a proximal end, a cannula opening into a lumen of the cannula assembly at the distal end, a cutting device coupled at the distal end and within the cannula opening; and an axial ball joint in the surgical tool, coupled to the proximal end of the cannula assembly, that when rotated, causes die cutting device at the distal end to rotate about a longitudinal axis passing axially through the lumen of the cannula assembly, so as to shear a portion of tissue at a target surgical site.

In some embodiments of the present invention, the sheared tissue portion may be used as a biopsy sample for pathology analyses. The surgical tool may be used to separate layers of tissue at any location in a body of a subject. The surgical tool, for example, may be used to remove a top layer of tissue and leave bottom layers of tissue intact at a target surgical site. In addition to using the surgical tool for eye surgeries and eye biopsy sample acquisition as shown hereinbelow, it may also be used, for example, in vacuum assisted biopsies, cancer biopsies, or dermatological biopsies.

Embodiments of the present invention hereinbelow farther describe a minimally invasive surgical instrument, which may be inserted through a small corneal incision to ablate a portion of the trabecular meshwork of the eye, thereby allowing for aqueous drainage in the treatment of glaucoma. Tissue removal may be achieved by mechanical means or other tissue destruction techniques.

The surgical instrument may also include an aspiration system. The aspiration system may be configured to remove ablated tissue, gas and bubble formation, and all intraocular debris generated. Trabecular meshwork tissue removed may be collected in a biopsy chamber for further analysis.

The surgical instrument may also be coupled to an infusion system to maintain and deepen the anterior chamber, so that easy access of the angle of the eye is obtained to the trabecular meshwork and Schlemm's canal. Infusion also allows fluid to flow out to the collector channels while the surgery is being performed, thus keeping the surgical site blood free and allowing the surgeon a clear view.

This surgical instrument provides a simple surgical solution for glaucoma treatment. It creates fenestrations of the Schlemm's canal like ELT, but with a much simpler and cheaper instrument. In some embodiments, the surgical instrument may combine the ease of use of mechanical devices such as the istent inject (Glaukos corporation) and the Hydrus stent (Ivantis), but does not leave any device in place which can potentially become blocked by iris or cause damage to the cornea. Other Microinvasive Glaucoma Surgery (MIGS) treatments, which bypass the TM and leave no device behind such as a Kahook Dual Blade (KDB), for example, are difficult to use. This may cause significant damage to the SC and may be more likely to cause damage to the neighboring tissue (e.g., iridodialysis and Descemet's membrane detachment) than a targeted and precise surgical trephining procedure. The Ab interno canalplasty procedure (ABiC) requires more expensive and sophisticated equipment and is technically more difficult to perform, however, it does retain the advantage that it may potentially be the only MIGS procedure that does expand the collector channels as well.

In summary, as a composite procedure that offers some of the advantages of the ELT procedure such as precise TM targeting and proven long term IOP control with cost savings and ease of use of the mechanical TM MIGS, this composite procedure offers some promise as a unique procedure, which is unhindered by prior art. This also strikes a balance between the more surgically destructive angle procedures like Gonioscopically assisted transluminal trabeculotomy (GATT) and KDB as well as the precise, but more unpredictable and expensive devices such as istent inject. Furthermore, if lower IOPs are to be achieved, one cannot implant more istent injects as these would be more expensive, but Minimally Invasive Trabeculotomy (MINT) as a repeatable procedure may deliver more trephines of the TM without additional cost. Thus, an optimum circumference of TM that may be targeted, or an optimum number of holes may be made. If an istent is inserted incorrectly, then it is nonfunctioning and that opportunity is lost. However, if a trephine is incorrectly sited, another is simply made in the right place thereby making the learning curve less steep.

The surgical instrument described herein based on clinical indications as described above may treat all forms of primary open angle glaucoma. In a similar manner to other MIGS, it may be suitable for treating the opened-up angle or the accessible part of the TM in angle closure glaucoma, but more likely to be successful as there is no bulky device left in situ to become blocked by iris or potentially cause chronic inflammation and its sequelae.

There are a variety of TM MIGS procedures on the market. With regard to the amount to TM excised or treated. MINT delivers more than istent inject and equivalent to the KDB, but not as much as the Gonioscopically assisted transluminal trabeculotomy (GATT) or Trab 360 procedure, which targets 360 degrees of the TM. With regard to ease of use, MINT is easier to perform than ABiC and Hydrus but may be slightly more difficult than istent inject. With regard to slow visual recovery due to blood in the anterior chamber, this would be less than KDB and GATT, but maybe equivalent to istent inject and Hydrus, in that there are similarly only small holes to let out blood as opposed to removal of large segments of the TM.

The main disadvantages of MINT compared to competing non TM MIGS devices such as Xen 45 (Allergan), Innfocus Microshunt, and CyPass (Alcon), for example, are the ability to lower the IOP to less than episcleral venous pressure, (e.g., 11 mm Hg). However, as a version of TM MIGS, conversely, they do have the advantage that the IOP will not drop below this level, leading to hypotony with sight threatening visual complications either. These unpredictable complications are difficult to avoid and require further surgery to manage. This hypotony cannot happen with TM MIGS.

In the embodiments of the present invention, the surgical instrument device may have the following characteristics, which may be achieved by appropriate device design, so as to reduce adjacent tissue damage, such as:

Ease of insertion: small tip profile of the surgical instrument device to be inserted through a 2.65 mm corneal wound.

Ease of ablation: cannula with a fixed cutting blade or cutting wire within hollow inner chamber, which can be inserted perpendicularly/tangential to the trabecular meshwork of the eye, and rotated along the longitudinal axis to provide a sheering action. Alternatively, a laser beam transmitted through the cannula may be used to ablate the target tissue.

Ease of aspiration: the ability to extract excised trabecular meshwork with minimal tissue manipulation or damage to surrounding tissue.

Minimal damage: The cannula tip outer wall profile may be curved inwards to prevent damage to surrounding trabecular meshwork even when the cannula tip is abraded across tissue surface.

The surgical instrument device for handheld ambidextrous one-handed use may have a form factor of a pistol, or a pen grip.

The surgical instrument device may be battery operated and fully portable.

The surgical instrument device may include a biopsy chamber for excised trabecular meshwork biopsy collection.

The surgical instrument device may include an optional infusion port which may be coupled to an infusion system to maintain and deepen the anterior chamber, and to irrigate the surgical site to keep the area blood free.

The surgical instrument device may include a cannula assembly, which may be a disposable, medically approved material for transient surgical use in the eye with a cutting blade or a cutting wire radially extended within cannula tip and flushed lip against the cannula tip.

The cannula may have a “dual hub” mechanism including two luer-lock junctions to form separate and independent chambers when connected to the handheld surgical tool.

The cannula may include a soft inflatable and flexible sheath wrapping along its length so as to provide infusion, wherein the irrigation fluid may be channeled out from one or more holes in the sheath near the distal end.

Embodiments of the present invention described herein relates to an ophthalmic surgical instrument and method for the treatment of glaucoma. The glaucoma may be various forms of open angle glaucoma (OAG). The method for the treatment of glaucoma may include the removal of a few small discrete portions of the trabecular meshwork (TM) by mechanical cutting, shearing, cautery, ablation, vaporization or any other suitable tissue destruction technique thus enabling unimpeded channels from the anterior chamber of the eye to the SC. The method also includes aspiration and collection of the excised tissue biopsy.

In some embodiments of the present invention, the surgical instrument may optionally include an apparatus to provide infusion into the anterior or posterior chamber of the eye.

In some embodiments of the present invention, the surgical instrument may include a disposable cannula attached to a handheld, portable surgical device. In other embodiments, the cannula may be disposable. The disposable cannula may be made from a disposable medically approved material for transient surgical use in the eye, with a cutting blade, or cutting wire radially extended within cannula tip and flush against with cannula tip. When inserted perpendicularly and tangentially to the trabecular meshwork of the eye and an aspiration may be applied by the handheld device, a portion of trabecular meshwork will be sucked into the cannula. The cannula may then be rotated along its longitudinal axis, so as to provide a shearing action with a clean ablation of trabecular meshwork within the hollow chamber. This shearing action may then be repeated on other points of the TM according to the desired TOP reduction.

The cannula may be accompanied by a tube miming parallel to the channel infusion, which maintains and deepens the anterior chamber, and irrigates the surgical site, so as to keep the area blood free for increased visibility. In another embodiment, a soft inflatable sheath (e.g. silicon) wrapping around the cannula may be used to provide infusion, where the irrigation fluid may be channeled out from holes formed in the sheath near the cannula tip.

In yet another embodiment, the cannula may be a laser probe capable of substantially complete tissue removal by cautery, vaporization, or other tissue destructive techniques. A fiber may be held within the probe, which directs light energy to the distal end of the probe tip, in close proximity of the trabecular meshwork to allow for cautery or vaporization of the tissue. The cannula with infusion capabilities may have a small tip profile for insertion through a 2.65 mm corneal wound.

In some embodiments of the present invention, the surgical instrument may be a battery operated handheld tool, which operates and controls the rotation of the cannula and infusion rate of irrigation fluid. The surgical instrument may include an electrical rotor for manipulating the cannula and enabling shearing of the TM tissue. The surgical instrument may include a collection chamber for the containment of the excised trabecular meshwork.

In some embodiments of the present invention, the surgical instrument may include a pump system to control aspiration or infusion, a battery to allow for portable operation, one of more trigger buttons to toggle the activation of the rotation and infusion, and an irrigation inlet, which may be optionally connected to either a separate infusion system, or embodied within the device. The surgical instrument may have a form factor of a pistol or a pen grip, or any other form factor suitable ambidextrous one-handed use.

In operation, the surgical instrument may provide IOP lowering effects by removing a portion of the trabecular meshwork, allowing free access of aqueous humor from the anterior chamber through to the Schlemm's canal that connects to the episcleral venous system, thereby to general circulatory system of the body. Multiple ablation sites may be performed at different clock hours (e.g., at different angles) radially around the meshwork (e.g., around eye40) for a larger drainage area so as to ensure exposing one or more of the collector channels.

The method for glaucoma treatment using the surgical tool as described herein is a simple, effective, low cost, minimally invasive, non-implantable glaucoma treatment option.

FIG.1schematically illustrates a hand10of a doctor holding surgical instrument15performing a Minimally Invasive Trabeculotomy (MINT) on an eye40, in accordance with some embodiments of the present invention. Surgical instrument15may also be referred to and used interchangeably herein as a MINT surgical instrument, a surgical tool, or a MINT surgical tool. Surgical instrument15may include a cannula assembly20, typically a disposable attachment, with a distal end23. Cannula assembly20may be configured to be inserted obliquely along an axis25into eye10via au incision35through a cornea45. Eye40as shown at the bottom ofFIG.1includes an eyelid32, a sclera34, a pupil31, and a corneal limbus38(e.g., corneal-scleral junction).

FIG.2schematically illustrates an enlarged view of eye40with distal end23of cannula assembly20positioned perpendicularly to a section of trabecular meshwork68, in accordance with some embodiments of the present invention.FIG.2schematically illustrates anatomical features in eye40. These anatomical features may include cornea45Schlemm's canal66, trabecular meshwork68, an iridocorneal at70, a ciliary epithelium71, a ciliary muscle72, corneal limbus38, iris36, a pars plicata76, a pars plana78, a sclera80, and a retina82.

In some embodiments of the present invention, cannula assembly20may be inserted through corneal wound incision35, typically with a length of 2.65 mm, for example along axis25. Corneal wound incision35may be made at any suitable place on cornea45, typically near corneal limbus38. Distal end23may be placed perpendicularly and tangentially to trabecular meshwork68of eye40(e.g., the target surgical site as shown by an arrow69inFIG.2) at different points along trabecular meshwork68as shown by arrows26inFIG.1. Arrows26may represent different trajectories of axis25through corneal wound incision35as the doctor navigates distal tip23of surgical tool15within the anterior chamber. Distal end23may include a blade30of any suitable configuration. When the cannula assembly20may be rotated, typically by 360 degrees along longitudinal axis25as shown in by an arrow87, a portion89of tissue of trabecular meshwork68may be excised. Portion89of eye tissue may be used as a biopsy tissue sample for examination to determine if glaucomatous or any other pathologic tissue may be present, for example.

In some embodiments of the present invention, surgical instrument15may be used to ablate portion89of trabecular meshwork68of eye40, so as to increase aqueous humor drainage and reduce IOP in the treatment of glaucoma.

In some embodiments of the present invention, surgical instrument15may include an aspiration system, such as a vacuum pump, for example, for aspirating excised biopsy tissue sample89along axis25by creating a vacuum88as shown by arrows. The aspiration system may be designed to remove ablated tissue, gas and bubble formation, as well as all other intraocular debris created during the surgical procedure. In other embodiments, the use of surgical instrument15is not limited to biopsies of the eyes glaucoma eye diseases, but may be used to collect biopsy samples for any other type of eye diseases (e.g., to excise any type of eye tissue).

Additionally, the aspiration system may be used in assisting the acquisition of biopsy tissue89from the trabecular meshwork. For example, vacuum88may suck the tissue into cannula assembly20where blade30may be rotated 360 degrees to twist and/or shear off the tissue sample where vacuum88may suck biopsy sample89into a collection chamber. In some embodiments, surgical instrument15may include a collection chamber for collecting aspirated biopsy tissue sample89.

In some embodiments of the present invention, surgical tool130may be coupled to an infusion system to inject irrigation fluid into eye40, so as to maintain and deepen the anterior chamber of eye40during the procedure. The deepen anterior chamber of eye40enables the ophthalmologic surgeon to insert distal end23into eye40along axis25with easy access to trabecular meshwork68and Schlemm's canal66. The irrigation fluid may be channeled out from distal end23of cannula assembly20while the surgery may be performed thus keeping the surgical site blood-free and may allow the surgeon to have a clear view of the surgical site. Stated differently, the irrigation fluid may be used to prevent the eye from collapsing during the medical procedure due to a loss of fluid, such as aqueous humor, for example.

In some embodiments, the irrigation fluid, or infusion fluid may include a balanced salt solution (BSS) for infusion. In other embodiments, the irrigation fluid may include medication that may be introduced into the eye during the medical procedure.

In some embodiments of the present invention, a time delay (e.g., a predefined time interval) between applying a vacuum to the tissue at the target surgical site and initiating rotation of the blade and infusion for washing the blood from the target surgical site may be used. A time delay in the range 0-1 seconds may ensure that enough negative pressure accumulates on the tissue at the target surgical site for sucking the tissue into distal end23before shearing the tissue with the cutting blade.

FIG.3Aschematically illustrates a first embodiment of surgical tool15with a pen grip form factor, in accordance with some embodiments of the present invention. The pen grip form factor may permit ambidextrous one-handed use. Surgical tool15with the pen grip form factor may include cannula assembly20that rotates about a cannula hub140, which is connected to the hand held portion of the surgical tool. In some embodiments, buttons100and102of surgical tool15may be assigned to activate a rotation/aspiration function and an infusion function.

In other embodiments, surgical tool15may have one or two buttons. In embodiments where one button is used, the one button may be toggled by the doctor between rotation, aspiration and/or infusion functions, for example. In some embodiments, the one button may not be present on the body of surgical tool15, but may be>implemented as a foot pedal, or an activation pedal, that may be coupled to surgical tool15to be used by a user (e.g., a doctor) so as to toggle between the rotation (e.g., cutting), aspiration and/or infusion functions of surgical tool15.

For example, after a surgeon creates a 1.8-2.7 mm incision on the cornea with a scalpel, the surgeon may insert distal end23of surgical tool15and navigate distal end23to the target surgical site (e.g., the trabecular mesh) and then operate the device by pushing the one button to toggle between the rotation (e.g., cutting), aspiration and/or infusion functions at the target surgical site.

FIG.3Bschematically illustrates a second embodiment of surgical tool130with a pistol form factor, in accordance with some embodiments of the present invention. In some embodiments, surgical tool130may include cannula hub140, cannula assembly20with distal end23, and a trigger135. Cannula assembly20may include an inflatable sheath110and a cannula105with blade30at distal end23. Cannula105may be connected to cannula hub140at a proximal end. Buttons133and135of surgical tool130may be assigned, for example, to activate a rotation/aspiration function and/or an infusion function.

FIG.4Aschematically illustrates cannula assembly20, in accordance with some embodiments of the present invention. A typical length of biopsy cannula assembly20is 20-25 mm.

FIG.4Bschematically illustrates cannula assembly20with a cutting blade152, in accordance with some embodiments of the present invention. This blade trephine embodiment may include blade152with an opening150with cross-sectional diameter typically 0.5 mm or larger.

FIG.4Cschematically illustrates an enlarged view of blade152, in accordance with some embodiments of the present invention. An opening150into the lumen of cannula105behind blade152.

FIG.4Dschematically illustrates a cross-sectional view of distal end23of cannula assembly20with blade152, in accordance with some embodiments of the present invention. Opening150may have a typical diameter of 0.5 mm or larger (e.g., diameter of cannula105). The distance from the cannula wall to the outer edge of cannula assembly20may typically be 0.15 mm as shown by arrow156. The width of blade152at marker154as shown inFIG.4Dmay typically be 0.22 mm. Blade152may extend radially mid-way within cannula tip (e.g., distal end23) and may be flush with or positioned close to cannula opening150. The cutting edge of the blade is parallel to cannula opening150.

In some embodiments of the present invention, the cannula tip curved profile may be curved inward at distal end23to prevent damage to the surrounding trabecular meshwork outside of the surgical site even when cannula distal end23may be abraded across the tissue surface at the surgical site during the operation. Blade152may be fixed to the inner wall of cannula assembly20, such that any tissue within the opening150will be twisted and/or sheared off when the cannula assembly20is rotated 360 degrees.

FIG.4Eschematically illustrates cannula assembly20with a cutting wire160, in accordance with some embodiments of the present invention. This embodiment illustrates an alternate wire trephine design where blade30may include cutting wire160.

FIG.4Fschematically illustrates a cross-sectional view of distal end23of cannula assembly20with cutting wire160, in accordance with some embodiments of the present invention. Cutting wire160may fully extend radially across the inner diameter of cannula opening150to provide shearing of the trabecular meshwork when rotated. As in the blade trephine embodiment, the cannula tip outer wall profile may be curved inward to prevent damage to the surrounding trabecular meshwork outside of the surgical site even when cannula distal end23may be abraded across the tissue surface at the surgical site. The width of cutting wire160may be typically 0.5 mm or larger.

FIG.5Aschematically illustrates cannula assembly20with inflatable sheath110attached to cannula hub140, in accordance with some embodiments of the present invention. Cannula105may include a first lumen144. A second lumen149is formed between sheath110and cannula105(e.g., an elongated tube105).

FIG.5Bschematically illustrates a right perspective view of cannula assembly20attached to cannula hub140, in accordance with some embodiments of the present invention.

FIG.5Cschematically illustrates a left perspective view of cannula assembly20attached to cannula hub140, in accordance with some embodiments of the present invention.

In some embodiments of the present invention, cannula assembly20may include cannula105attached to cannula hub140. In other embodiments, cannula assembly20may include a soft inflatable sheath wrapping to (e.g., sheath110) to provide infusion where the irrigation fluid may be channeled out from one of more outlet holes142near distal end23.

In some embodiments of the present invention, the soil inflatable sheath wrapping may be in a form of a tube running parallel (e.g., sheath110) to cannula105to channel the infusion liquid into the chamber of eye40. The direction of the infusion liquid flow in sheath110and out of outlet holes142(e.g., via second lumen149) may be seen in bothFIGS.5B and5Cby the arrows. Cannula hub140may be attachable to the surgical tool15and one or more holes148in cannula hub140may allow the irrigation fluid to flow into sheath110of cannula assembly20via holes148.

Similarly, sheared tissue sample89from trabecular meshwork68may be aspirated through first lumen144of cannula105from distal end23. Sheared tissue sample89may be transported by vacuum88through first lumen144to a proximal end24of cannula105where first lumen144is coupled to a central hole145in cannula hub140in a manner permitting rotation87of cannula105. Threading146in cannula hub140may be used to join and fix to cannula hub140to a locking interface on surgical tool15. Sheared tissue sample89may be transported into a biopsy collection chamber in surgical tool15.

In the embodiments shown inFIGS.5A-5C, cannula hub140may include two luer-lock junctions to form separate and isolated chambers when connected to surgical handheld device15. The two isolated chambers (e.g., first lumen144and second lumen149) allow the independent flow of irrigation fluid within the outer hub via the one or more holes148out to sheath110, and aspiration through cannula first lumen144.

FIG.6schematically illustrates a cross-sectional side view of surgical tool130with a pistol form factor, in accordance with some embodiments of the present invention. Surgical tool130may include cannula assembly20with distal end23and proximal end24connected to cannula hub140. Cannula hub140may be attached to a body172of surgical tool130. The elements of body172ate shown inside the box defined with a dotted line as shown inFIG.6. Body172may include trigger135, an axial ball joint175for 360-degree rotation of cannula105, a biopsy collection chamber170, and an irrigation fluid inlet180for introducing irrigation fluid for balanced salt solution (BSS) drip infusion, for example. In body172, irrigation fluid may flow from inlet180into an infusion tube188coupled to axial ball joint175.

In some embodiments, as shown in an inset169, biopsy collection chamber170may include a sieve171for capturing pieces173of tissue from the sheared portion89that may break into pieces173while traveling from distal end23and before reaching biopsy collection chamber170. Sieve171may be of any suitable size and/or shape for improving flow rate. Sieve171may have a hemispherical shape as shown inFIG.6. Sieve171may be flat, conical (e.g., triangular), or dome shaped. Sieve171may be a membrane with partial coverage within biopsy collection chamber170. It may be placed at the entrance to biopsy collection chamber170or may be positioned anywhere within biopsy collection chamber170. Sieve171may include holes as shown as the gaps in the dotted line representing sieve171. The holes in sieve171may be circular or square shaped, each hole ranging in size from 20 μm to 1 mm.

In some embodiments of the present invention, axial ball joint175(or any suitable similar mechanism) may be used to rotate87the cannula105while pumping irrigation fluid into sheath110, while channeling ablated tissue sample89into biopsy collection chamber170via tubes184and186in body172. Tube184may be coupled to first lumen144. Axial ball joint175pumps the irrigation fluid into a tube182(e.g., a continuation of infusion tube188) coupled to cannula hub140and into the proximal end of sheath110via holes148. The irrigation fluid may be pumped from proximal end24to distal end23of cannula assembly20in sheath110, so as to exit from the one of more outlet holes142near distal end23into the surgical site.

Insert106inFIG.6illustrates a cross-section of cannula assembly20with arrows107showing the direction the irrigation fluid in sheath110, and an arrow109showing the direction of aspiration (e.g., vacuum88) in cannula105(e.g., in fast lumen144).

FIG.7Aschematically illustrates a locking interface141, in accordance with some embodiments of the present invention.

FIG.7Bschematically illustrates a cross-sectional view of locking interface141, in accordance with some embodiments of the present invention.

Handheld surgical tool130and15may include locking interface141for attaching or screwing cannula hub140of cam la assembly20(e.g., threading146) onto a male type connector (or any suitable mating connector) on body172with threading147so as to attach and hold the disposable cannula assembly to the body of the MINT surgical instrument. The dual hub design shown inFIGS.7A and7Bof the disposable cannula (e.g., cannula105) allows the independent and separate flow107of irrigation fluid (e.g., infusion) within second lumen149in outer sheath110and aspiration flow109in first lumen144of cannula105.

In some embodiments of the present invention, surgical tool130may include an electrical motor to rotate the cannula and enable shearing of the biopsy tissue at the surgical site.

In some embodiments of the present invention, surgical tool130may include a pump system to form vacuum88in first lumen144, so as to suck biopsy tissue sample89into biopsy collection chamber170for collecting the trabecular meshwork biopsy sample.

In some embodiments of the present invention, irrigation inlet180may be connected to a separate infusion system, or may be included in surgical tool130itself.

In some embodiments of the present invention, trigger135may be used to toggle the activation of the cannula rotation and infusion of irrigation fluid to the surgical site.

In some embodiments of the present invention, trigger135may be used to activate the rotation of cannula105and the suction of biopsy sample89into biopsy collection chamber170.

In some embodiments of the present invention, a liquid-air membrane or valve may be used to separate biopsy collection chamber170and a vacuum system.

In some embodiments of the t invention, surgical tool130may include a battery for portable operation.

In some embodiments of the present invention, trigger135may be positioned at the front of body172of surgical tool130for finger operation as shown inFIG.6. In other embodiments, trigger135may be positioned at the back of body172of surgical tool130for thumb operation.

In some embodiments of the present invention, a peristaltic pump may be located in body172between inlet180and biopsy collection chamber170so as to eliminate the need for a liquid-air membrane or valve mechanism.

In some embodiments of the present invention, surgical tool130may include one or more finger grips when surgical tool130may be operated as a syringe.

In some embodiments of the present invention, surgical tool130may have infusion provided by a tithe running parallel to cannula105.

FIG.8Aschematically illustrates a side view of a third embodiment of a surgical tool200, in accordance with some embodiments of the present invention.

FIG.8Bschematically illustrates a perspective view of a third embodiment of surgical tool200, in accordance with some embodiments of the present invention.

Surgical tool200may include a cannula assembly210with an outer tube214as shown in an inset212, a stepper motor216, a back cup adapter218, an end cup fixation screw220, an air/vacuum tube swivel connector222, a deep groove flanged ball bearing224for supporting tube210while rotating, a front bearing adapter226, a second deep groove flanged ball bearing228, a front connecting tube230, a body232(e.g., surgical tool outer shell), an end cup234, an electric power line236, and a vacuum line240.

In various embodiments, cannula assembly210may be formed from a surgical steel 23G tube with welded on cutting features. Outer tube214may be formed from a surgical steel 19G tube. Stepper motor216may include a 20 mm hollow shaft stepper motor. Back cup adapter218may include a nylon friction coupling device—clamps, cutter tube, motor and swivel connector. End cup fixation screw220may include an M3 screw. Air/vacuum tube swivel connector222may be a 6 mm Air/vacuum tube swivel connector. Front bearing adapter226may be formed from a precision milled stainless hollowed shaft. Front connecting tube230may include a nylon friction coupling device clamps, cutter tube, motor and swivel connector. Electric power line236may include a JST2.0 PH 6 pins to 4 pins type electrical line. Vacuum line240may include a 6×4 mm air/vacuum line.

FIG.9Aschematically illustrates a side view of a second embodiment of a cannula assembly305, in accordance with some embodiments of the present invention.

FIG.9Bschematically illustrates a perspective view of a second embodiment of cannula assembly305, in accordance with some embodiments of the present invention.

FIG.9Cschematically illustrates a cross-sectional view of a second embodiment of cannula assembly305, in accordance with some embodiments of the present invention.

In some embodiments of the present invention, a distal end300of cannula assembly305(e.g., inner tube305) may be placed within an outer tube310passing axially along a longitudinal axis through the cannula opening. A cutting blade320may be placed flush or near the cannula opening (e.g., at a slight distance 0-10 mm away from the cannula opening) as shown inFIG.9C. Cannula assembly305may be rotatable within outer tube310. In some embodiments, outer tube310may not be rotatable or fixed in place so as to avoid inducing disturbances in the surrounding tissue near the target surgical site and to merely provide better suction at a distal tip315contacting the tissue at the target surgical site.

In some embodiments of the present invention, distal end300of cannula assembly305may have a distal tip315that is beveled where an angle y shown inFIG.9Amay be in the range of 0-90 degrees. The beveled tip may provide a more uniform suction when distal tip315when contacting eye tissue at typical angles in the peripheral anterior chamber of the eye.

FIG.10schematically illustrates a system350for controlling surgical tool200for shearing tissue at a target surgical site, in accordance with some embodiments of the present invention. System350may be used, for example, to performing a Minimally Invasive Trabeculotomy (MINT) on an eye of a patient. System350may include a control box400coupled to vacuum line240of surgical tool200(e.g., as shown inFIGS.8A and8B) via a fluid separator410. Control box400may include an ON/OFF switch355, an LCD display360, and a control knob365for controlling the rotation speed of blade30cannula assembly210). A vacuum pump390may be coupled to control box400, where vacuum pump390may include a vacuum regulating valve385, a vacuum gauge395and a vacuum inlet397. An activation (foot) pedal380may be coupled to control box400via a pedal control line370. Activation pedal380may be used by a user (e.g., a doctor) for controlling surgical tool200. Activation pedal380may be used to toggle between the rotation (e.g., cutting), aspiration and/or infusion functions of surgical tool200.

In some embodiments of the present invention, surgical tool15may include a laser generator and a cannula. The cannula may be a laser probe capable for the substantially complete tissue removal by ablation, vaporization or cautery. The laser probe may include a fiber to direct light energy to the distal end of the probe tip and into the surgical site (e.g., in close proximity to the trabecular meshwork to allow for cautery or vaporization of the tissue.) Surgical tool15may include an infusion/aspiration inlet, which may be optionally connected to a separate infusion system.

In some embodiments of the present invention, surgical tool15may include a laser generator and a cannula. The cannula may be a laser probe capable for the substantially complete tissue removal by ablation, vaporization or cautery. However, one or more optical fibers for conducting the laser beam may be arranged for example, in a bundle. The bundle may be held together with cladding may be used to direct light energy to the distal end of the probe tip and into the surgical site (e.g., in close proximity to the trabecular meshwork to allow for cautery or vaporization of the tissue.)

In some embodiments of the present invention, a surgical tool for shearing tissue at a target surgical site may include a cannula assembly with a distal end and a proximal end, a cannula opening into a lumen of the cannula assembly at the distal end a cutting device coupled at the distal end and within the cannula opening, and an axial ball joint in the surgical tool, coupled to the proximal end of the cannula assembly, that when rotated, causes the cutting device at the distal end to rotate about a longitudinal axis passing axially through the lumen of the cannula assembly, so as to shear a portion of tissue at a target surgical site.

In some embodiments of the present invention, the target surgical site may be a trabecular meshwork of an eye of a subject.

In some embodiments of the present invention, the distal end of the cannula assembly may have a curved inward tip profile.

In some embodiments of the present invention, the distal end of the cannula assembly may have a beveled tip.

In some embodiments of the present invention, the surgical tool may include an outer tube, where the cannula assembly may be placed within the outer tube passing axially along the longitudinal axis and the cannula assembly is rotatable within the outer tube.

In some embodiments of the present invention, the outer tube may not be rotatable.

In some embodiments of the present invention, the cutting device may extend radially mid-way within the cannula or may be flush with the cannula opening.

In some embodiments of the present invention, the cutting device may be a surgical cutting blade.

In some embodiments of the present invention, a surgical tool for shearing tissue at a target surgical site may include cannula assembly20. Cannula assembly20with distal end23and proximal end24, may include an elongated tube (e.g., cannula105) within flexible sheath110along longitudinal axis25passing axially through first lumen144of elongated tube105, wherein second lumen149is formed between sheath110and elongated tube105along longitudinal axis25. Surgical blade30may be coupled to elongated tube105at distal end23. Connector hub140may be attached to body172of the surgical tool may comprise central inner hub hole145and one or more outer hub holes148coupled to cannula assembly20at proximal end24. Elongated tube105may be placed within central inner hub hole145in connector hub140. One or more outer hub holes148in connector hub140may be coupled to second lumen149. Axial ball joint175in body172of the surgical tool, may be coupled to elongated tub105at proximal end24of cannula assembly20, that when rotated87, causes surgical blade30at distal end23to rotate87about longitudinal axis25, so as to shear portion89of tissue at a target surgical site.

In some embodiments of the present invention, the sheared portion may include eye tissue excised from a trabecular meshwork of eye40.

In some embodiments of the present invention, the surgical tool may include a biopsy collection chamber in the body for collecting the sheared portion of tissue.

In some embodiments of the present invention, the biopsy collection chamber may include a sieve for capturing pieces of the tissue from the sheared portion.

In some embodiments of the present invention, the surgical tool may include a vacuum pump configured to suck the portion into the first lumen at the distal end prior to shearing the portion with the surgical blade.

In some embodiments of the present invention, the surgical tool may include a vacuum pump configured to suck the sheared portion through the first lumen into the biopsy collection chamber.

In some embodiments of the present invention, the surgical tool may have a pistol form factor.

In some embodiments of the present invention, the surgical tool may have pen grip form factor.

In some embodiments of the present invention, the surgical blade may extend radially mid-way at an opening into the first lumen at the distal end.

In some embodiments of the present invention, the surgical blade may include a cutting wire.

In some embodiments of the present invention, the surgical tool may include an infusion tube in the body of the surgical tool coupled to the second lumen at the proximal end of the cantina assembly through the one or more outer hub holes.

In some embodiments of the present invention, the surgical tool may include an irrigation fluid inlet formed in the body of the surgical tool and coupled to the infusion tube.

In some embodiments of the present invention, the flexible sheath may include outlet holes into the second lumen near the distal end of the cannula assembly, wherein irrigation fluid introduced through the irrigation fluid inlet in the body of the surgical tool may pass through the outlet holes at the distal end to irrigate the target surgical site.

In some embodiments of the present invention, the surgical tool may include a motor for rotating the axial ball joint.

In some embodiments of the present invention, the distal end is curved inward.

In some embodiments of the present invention, the surgical tool may include a button that may be pushed by a user to toggle between cutting, aspiration, or infusion functions at the target surgical site.

In some embodiments of the present invention, a method for shearing tissue at a target surgical site may include navigating a distal end of a cannula assembly of a surgical tool to a target surgical site, wherein the surgical tool may include:

the cannula assembly with the distal end and a proximal end, may include an elongated tube within a flexible sheath along a longitudinal axis passing axially through a first lumen of the elongated tube, wherein a second lumen is fanned between the sheath and the elongated tube along the longitudinal axis;

a surgical blade coupled to the elongated tube at the distal end;

a connector hub attached to a body of the surgical tool may include a central inner hub hole and one or more outer hub holes coupled to the cannula assembly at the proximal end;

wherein the elongated tube is placed within the central inner hub hole in the connector hub, and wherein the one or more outer hub holes in the connector hub are coupled to the second lumen; and

an axial ball joint in the body of the surgical tool, coupled to the elongated tube at the proximal end of the cannula assembly, that when rotated, causes the surgical blade at the distal end to rotate about the longitudinal axis; and

shearing a portion of tissue at the target surgical site by rotating the axial ball joint.

In some embodiments of the present invention, shearing the portion of tissue may include excising eye tissue from a trabecular network of an eye.

In some embodiments of the present invention, the method may include obtaining a biopsy sample by applying a vacuum to the first lumen, so as to suck the sheared portion through the first lumen into a biopsy collection chamber.

In some embodiments of the present invention, the method may include irrigating the target surgical site with irrigation fluid passing through outlet holes in the flexible sheath from the second lumen near the distal end of the cannula assembly.

In some embodiments of the present invention, the method may include sucking the portion of eye tissue at the target surgical site into the first lumen at the distal end prior to shearing the portion with the surgical blade.

In some embodiments of the present invention, the method may include, within a predefined time interval after sucking the tissue portion into the first lumen at the distal end, shearing the tissue portion with the surgical blade at the target surgical site and irrigating the target surgical site with irrigation fluid.

Different embodiments are disclosed herein. Features of certain embodiments may be combined with features of other embodiments; thus certain embodiments may be combinations of features of multiple embodiments. The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. It should be appreciated by persons skilled in the art that many modifications, variations, substitutions, changes, and equivalents are possible in light of the above teaching. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.

While certain features of the invention have been illustrated and described herein, many modifications, substitutions, changes, and equivalents will now occur to those of ordinary skill in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.