The field of disclosure relates to devices for use during ophthalmic surgery. More particularly, the field of disclosure relates to devices for performing surgical manipulation of the sclera during surgical procedures performed on the eye.
Glaucoma, the leading cause of irreversible blindness in the world, is a group of diseases affecting the optic nerve, frequently characterized by increased intraocular pressure (i.e., pressure within the eye). Patients suffering from glaucoma are typically initially managed with medical therapy. However, some patients are unable to tolerate medication or do not adhere to their drug regimens, and, consequently, may require surgical intervention to preserve their vision. In some cases, when glaucoma continues to progress despite the use of medication regimes and/or laser treatments (e.g., laser trabeculoplasty), a glaucoma filtration procedure (e.g., trabeculectomy, non-penetrating deep sclerectomy, etc.) may be recommended.
Most glaucoma filtration surgical techniques (e.g., trabeculectomy, non-penetrating deep sclerectomy, etc.) involved an initial required step of performing scleral flap, in which one-third to one-half of the scleral thickness (i.e., the thickness of the sclera, which is the white outer layer of the eye) is dissected to the clear cornea. The procedure of manually performing scleral flap with manual surgical instruments (e.g., blades, knives, etc.) is both technically demanding and time-consuming to perform properly (i.e., to create a flap that is uniform and has the appropriate thickness and size). There are many risks and complications associated with the scleral flap procedure which can impact the outcome of the procedure. For example, too deep or too shallow thickness of the scleral flap can influence both the short-term and the long-term outcome of the procedure. In addition, rupture of the scleral flap during preparation of the scleral flap can prevent using the necessary control on aqueous outflow using uniform and/or complete scleral flap covering/closure on the filtration area.
Too deep of a scleral flap during glaucoma procedure such as trabeculectomy or non-penetrating deep sclerectomy is leading to generation of a thick flap that is applying excessive load and pressure on the filtration area directly or its pathway that leading to failure of the surgical procedure; the too deep flap is too thick and can provide excessive resistance to aqueous outflow due to the increased weight of the sclera in the flap on the aqueous outflow that can blocks the filtration area directly or the aqueous outflow. Additionally, too deep can result in penetration into the anterior chamber or the choroid layer, requires converting a non-penetrating surgery into a penetrating procedure (e.g., trabeculectomy). Exposure of the choroid or the ciliary body can result in excess inflammatory reaction that can affect the outcome of the procedure. For example, such inflammation can accelerate the scarring process, resulting in limiting the duration of effectiveness of the surgery.
Too thin scleral flap can prevent the provision of the necessary resistance to outflow when performing aggressive penetrating procedure (e.g. trabeculectomy), and the risk for hypotony-related complications is higher. In addition, when performing CO2 Laser Assisted Deep Sclerectomy, which is laser-based non-penetrating surgery by ablating the sclera, the key for successful operation is anatomical identification for the correct scan pattern positioning. However, when too thin a scleral flap is present, the anatomical landmarks are not clear and can result in misplacement of the scan pattern. Additionally, too thin of a scleral flap can result in non-effective sutures required for closure of the scleral flap above the filtration area. Thus, the required controlled resistance to aqueous outflow with the scleral flap cannot then be achieved.
Scleral flap of non-uniform thickness can have negative consequences for CO2 Laser Assisted Sclerectomy. In this procedure, the laser that is used ablates equally in all areas of a scanning pattern. Thus, if the scleral flap is non-uniform, the ablations will keep the same non-uniformity of the tissue, resulted in areas that are deep ablated and exposed, and in areas that are less ablated and therefore less exposed; to get the optimal result of even exposure, the non-uniform scleral flap leading to excessive required ablations, and is causing to elongation of the procedure with the laser system.
Cataracts are the leading cause of blindness worldwide with the majority of cases in developing nations. The leading techniques for performing cataract surgery are extracapsular cataract extraction (ECCE), small incision cataract surgery (SICS), and phacoemulsification. The most common technique, phacoemulsification, has become the standard of care, but requires very expensive phacoemulsification equipment, which may not be available at all centers, especially in developing countries.
Manual scleral flap during cataract surgery is required in places where the availability of phacoemulsification equipment is limited, or in cases when the phacoemulsification surgery requires conversion into a manual technique (ECCE or SICS) due to complications, or when the cataract condition (i.e. too rigid lens) is not effective for the use of phacoemulsification surgery due to limitations of phacoemulsification equipment; in such cases it is required for the surgeon to perform a manual technique (ECCE or SICS), and understand the key principles for these manual procedures.
ECCE is a technique in which a portion of the anterior capsule of the lens is removed, allowing extraction of the lens nucleus and cortex, leaving the remainder of the anterior capsule, the posterior capsule, and the zonular support intact. This is the case in all the present cataract surgery techniques (i.e., ECCE, SICS and phacoemulsification). By convention, however, ECCE refers to a procedure in which the intact lens nucleus is removed from the eye through a scleral flap including limbal incision (i.e. incision is made in the limbus line), which include the following dimensions: it is about 10-12 mm in standard extracapsular surgery, about 5.5-7.0 mm in manual small incision surgery (“MSICS”), and about 3-5.5 mm in instrumental phacoemulsification, depending upon the technique and implant.
One of the key surgical steps in SICS and ECCE, which dramatically influences the efficacy and safety of the manual procedures, is the scleral incision or scleral tunnel (also called the sclerocorneal pocket), which relies upon intraocular pressure to close the internal lip of the wound, thereby creating a self-sealing wound and eliminating post-operative suture-induced astigmatism. Wound construction is of vital importance in SICS and ECCE. The ultimate outcome and the ease of delivering the nucleus are dependent on wound architecture.
SICS in comparison to ECCE, requires a smaller scleral incision, and its scleral closure performed with no sutures (sutureless); In comparison ECCE requires much bigger scleral opening, and therefore requires sutures for its closure. Two important aspects of the incision for SICS are the self-sealing nature of the wound and the possibility of induced astigmatism. For a wound to be self-sealing, it should conform to the principle of “quadrangular or square incisional geometry.” This is a general concept which states that an ideal self-sealing wound has a length equal to its width. However, the length is usually smaller, and there is a relationship between the probability that a wound is self-sealing and its approximation to quadrangular or square geometry. There are two incisions in the scleral tunnel wound for SICS: the external scleral incision and the internal corneal incision. The external wound dimensions have an important bearing on the self-sealing nature of the wound, with smaller incisions being more reliably self-sealing than larger ones. A small external wound, however, presents an obstacle to the delivery of the nucleus and IOL implantation. Hence, the incision should be fashioned in a way which lends itself to stretching. The dimension of the wound depends upon the preoperative assessment of the nucleus size and the technique used to deliver the nucleus (phacosandwich or snare or pre-chopper will help reduce incision size, whereas use of wire vectis will require a larger incision width). There are two commonly-used types of external incisions. The frown incision is a parabolic groove convex towards the limbus with the center being 1.5-2 mm behind the limbus and chord length being 6-7 mm. The other incision is the straight scratch incision 5-6.5 mm in length, 1.5 mm behind the limbus, and with backward extensions at both ends creating side pockets. The internal incision is in the cornea and does not lend itself to stretching. Consequently, it should be made large enough to accommodate the nucleus or the implant. Generally, an 8-9 mm inner lip suffices. The internal incision should be parallel to the limbus. It should extend to the limbus but should not cut the limbus on either side. These features give the maximal security and anti-astigmatic effect to the wound.
Consequently, the properties of a self-sealing wound for SICS include an approximation of quadrangular or square geometry, a relatively small external incision with a geometrical shape that lends itself to stretching, and a tunnel that flares to a larger internal incision. The self-sealing is ensured by the remoteness of the two incisions brought about by the collapsed tunnel in normal conditions.
The other important aspect of wound construction is the induced astigmatism caused by the wound, which should be minimal, and if possible favorable, to counteract existing astigmatism. Corneal wounds cause the greatest, limbal intermediate, while scleral wounds cause least astigmatism. Temporal wounds are purported to cause less astigmatism than superior wounds, and have a counterbalancing effect on the natural ATR shift that occurs with age. However, most surgeons are familiar with the superior location, and the larger wound size and conjunctival dissection in SICS make this site less appropriate for wound placement. An important concept in understanding incision design in SICS is that of the incisional funnel. This is an area bounded by a pair of curvilinear lines whose shape is based upon the relationship between astigmatism and two characteristics of the incision—length and distance from limbus. Incisions made within this funnel are astigmatically stable. Short linear incisions made close to the limbus and longer incisions farther away are equally stable. A frown incision or a chevron-shaped incision incorporate a larger incision into this funnel, and hence are more desirable. Though moving farther away from the limbus makes an incision more stable, it increases the surgical difficulty by limiting access and maneuverability. Clear corneal tunnels have significant demerits: difficulty in obtaining quadrangular or square geometry due to limited length of tunnel, difficulty in anterior chamber manipulation or “oarlocking,” and less security due to long healing time and lack of fibrosis.
The scleral tunnel must be constructed while a proper plane of dissection is maintained and wound architecture is not destroyed. The desired size of the external wound is measured with a caliper and marked behind the limbus. The frown convexity should be 1-1.5 mm behind the limbus and the ends about 3 mm. Similarly, the ends of the straight incision lie about 2 mm behind the limbus. The external incision is about 0.3 mm deep and should be of uniform depth. Conscious effort is made to tilt the knife along the contour of the cornea to maintain uniformity of the tunnel roof and avoid buttonholing laterally. Complications can occur at each of the above steps while making the tunnel incision. Too superficial an external wound will cause a thin superficial flap or may result in buttonholing of the flap. In such a situation, the groove can be deepened and dissection started at a deeper plane without compromising the tunnel. Too deep a groove will increase the difficulty of corneal dissection and increase the chances of a premature entry into the anterior chamber. Scleral disinsertion can occur due to a deep groove and will result in large amount of postoperative ATR astigmatism. In both situations, radial sutures are necessary to ensure secure wound closure and prevent postoperative astigmatism. A tear of the lateral edge of the external wound is common, especially when too much force is being applied during dissection due to a blunt instrument. This happens due to the slight anterior rotation of the crescent knife during anterior dissection. If large, this can be repaired at the end of the surgery with 10-0 suture. Undue haste during tunnel dissection can lead to a premature entry into the anterior chamber. This leads to compromise of the features of the tunnel and creates problems during surgery like iris prolapse, etc. This is best prevented. It may become necessary to close the wound and initiate a new one at another site. If the inner lip has not been properly fashioned, it is better to use sutures to close the incision to prevent postoperative complications. A blunt keratome while making the internal incision or side port entry can cause a Descemet's membrane detachment. In such an eventuality, the membrane must be uncurled and kept in position using an air bubble tamponade. It may be sutured back in place if the detachment is large. Blunt instruments necessitating the use of undue force can lead to sudden uncontrolled entry into the AC and injury to the iris and lens, including zonular dialysis.
Some embodiments of the disclosure is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of embodiments of the disclosure. In this regard, the description taken with the drawings makes apparent to those skilled in the art how embodiments of the disclosure may be practiced.
The exemplary embodiments relate to a device for guiding a cutting blade during surgical manipulation of the sclera. The exemplary embodiments also relate to a system including a cutting blade and a device for guiding the cutting blade during surgical manipulation of the sclera (alternately referred to herein as a “guidance device”). The exemplary embodiments also relate to a method for using a depth-control cutting blade and a device for guiding the cutting blade to perform surgical manipulation of the sclera in a desired shape, size, and thickness.
In an embodiment, a guidance device for performing surgical manipulation of a sclera of an eye of a patient includes a guidance element configured to be positioned adjacent to the sclera, the guidance element including a horizontal cutting slot configured to receive a cutting blade and guide motion of the cutting blade so as to make a horizontal cut through the sclera, the guidance element also including a blade entrance slot configured to receive the cutting blade and guide motion of the cutting blade so as to make a layering cut parallel to the sclera and through a portion of the sclera, thereby separating a desired layer of separated sclera tissue from the rest of the underlying sclera. In an embodiment, the separated sclera tissue has a quadrilateral profile. In an embodiment, the quadrilateral profile is rectangular. In some embodiments, the rectangular profile has a height in the range of 1 mm to 6 mm and a width in the range of 2 mm to 12 mm.
In an embodiment, the guidance device also includes first and second vertical cutting slots, each of the first and second vertical cutting slots configured to receive the cutting blade and guide motion of the cutting blade so as to make corresponding first and second vertical cuts through the sclera, the first and second vertical cuts being parallel to one another and perpendicular to the horizontal cut, whereby the first vertical cut, the second vertical cut, the horizontal cut, and the layering cut define a scleral flap having desired dimensions. In an embodiment, the scleral flap has a quadrilateral profile. In an embodiment, the quadrilateral profile is a rectangular profile. In an embodiment, the rectangular profile is a square profile. In an embodiment, the square profile has an edge length of between 2 millimeters and 5 millimeters. In an embodiment, the rectangular profile has a height in the range of 1 mm to 6 mm and a width in the range of 2 mm to 12 mm. In an embodiment, the quadrilateral profile is a trapezoidal profile. In an embodiment, the trapezoidal profile has a height in the range of 1 mm to 6 mm and a maximum width in the range of 2 mm to 12 mm.
In an embodiment, the guidance device includes a vacuum mechanism configured to apply a suction force to the sclera so as to pull the sclera upward for a reproducible blade penetration within the tissue, for facilitating movement of the cutting blade, and for reproducible cutting of the desired layer thickness from the rest of the underlying tissue. In some embodiments, the vacuum mechanism is integrated into the guidance device. In some embodiments, the vacuum mechanism includes a connection to an external vacuum source.
In some embodiments, the guidance device includes a handle. In some embodiments, the handle is positioned adjacent to the horizontal cutting slot. In some embodiments, the guidance device includes first and second vertical cutting slots, and the handle is positioned adjacent to the first vertical cutting slot.
In some embodiments, the guidance device includes anchoring elements configured to retain the guidance device in proximity to the sclera. In some embodiments, the anchoring elements include needles. In some embodiments, the anchoring elements include pins.
In some embodiments, the guidance device includes an aiming mechanism configured to facilitate correct positioning of the guidance device with respect to the eye. In some embodiments, the aiming mechanism includes an arc-shaped portion. In some embodiments, the arc-shaped portion is configured so as to overlay a limbus line when the guidance device is correctly positioned with respect to the eye.
Some exemplary embodiments relate to a kit comprising the guidance device and one or more surgical knives. In some embodiments, the one or more surgical knives comprise two separate knives each with a single blade. In some embodiments, the single blades are the same. In some embodiments, the single blades are different. In some embodiments, the one or more surgical knives can comprise a single double-ended surgical knife. In some embodiments, each blade of the double-ended surgical knife is the same. In some embodiments, each blade of the double-ended surgical knife is different.
Among those benefits and improvements that have been disclosed, other objects and advantages of this disclosure will become apparent from the following description taken in conjunction with the accompanying figures. Detailed embodiments of the present disclosure are disclosed herein; however, it is to be understood that the disclosed embodiments are merely illustrative of the disclosure that may be embodied in various forms. In addition, each of the examples given in connection with the various embodiments of the disclosure which are intended to be illustrative, and not restrictive.
Throughout the specification and claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise. The phrases “in one embodiment,” “in an embodiment,” and “in some embodiments” as used herein do not necessarily refer to the same embodiment(s), though it may. Furthermore, the phrases “in another embodiment” and “in some other embodiments” as used herein do not necessarily refer to a different embodiment, although it may. Thus, as described below, various embodiments of the disclosure may be readily combined, without departing from the scope or spirit of the disclosure.
As used herein, the term “based on” is not exclusive and allows for being based on additional factors not described, unless the context clearly dictates otherwise. In addition, throughout the specification, the meaning of “a,” “an,” and “the” include plural references. The meaning of “in” includes “in” and “on.”
In some embodiments, a system includes an ophthalmic surgical blade and a device for guidance of the surgical blade. In some embodiments, the ophthalmic surgical blade is a crescent blade. In some embodiments, the guidance device is configured to guide the surgical blade to perform a cut having the required depth and dimensions of the scleral flap. In some embodiments, the guidance device is configured to maintain the blade in an orientation substantially parallel to the surface of the eye and to prevent angular movement of the blade upward or downward, thereby ensuring the generation of a uniform flap (i.e., preventing the generation of too thick or thin of a flap). In some embodiments, the guidance device is configured to define the thickness of the scleral flap by directing the blade entrance into the tissue at specific depth/thickness. In some embodiments, the guidance device is configured to affect the shape and size of the flap. In some embodiments, the guidance device includes slots for directing knife working positions, and is thereby configured to dictate the size and dimensions of the flap. In various embodiments, slots can be differently sized and shaped so as to be configured to enable generation of the scleral flap in the desired shape (e.g., rectangle, square, trapezoidal) and dimensions.
In some embodiments, a method includes placing a guidance device on a patient's eye at a location where a scleral flap is to be created, whereby anchoring elements anchor the guidance device to the patient's eye; operating a vacuum mechanism to facilitate entry of a blade into the sclera of the patient's eye; inserting a blade into a blade entrance slot of the guidance device; moving the blade within the blade entrance slot to create a bottom of a layer of the sclera; removing the blade from the blade entrance slot; placing the blade in a horizontal slot of the guidance device; moving the blade within the horizontal slot to define an end of the scleral flap; removing the blade from the horizontal slot; placing the blade in a first vertical slot of the guidance device; moving the blade within the first vertical slot to define a first side of the scleral flap; removing the blade from the first vertical slot; placing the blade in a second vertical slot of the guidance device; moving the blade within the second vertical slot to define a second side of the scleral flap; and removing the blade from the second vertical horizontal slot; placing the blade in a first vertical slot of the guidance device; whereby the bottom of the layer, the first side, the second side, and the end define a scleral flap.
In some embodiments, the guidance element 104 is not configured to cooperate with a vacuum source to attach the guidance device 100 to the eye during surgery. Accordingly, in some embodiments, such as the embodiment of
Continuing to refer to
Continuing to refer to
In some embodiments, the guidance element 104 is configured so as to limit the depth of cuts that are made using the horizontal slot 204 and the vertical slots 206, thereby controlling and limiting the depth of a scleral flap. In some embodiments, the horizontal slot 204 and the vertical slots 206 are configured to cooperate with a stopper that is integrated with the handle of a cutting blade so as to limit the depth of cuts.
Accordingly, some embodiments of the present disclosure are configured to control the depth of the blade penetration into the guide slot, and thereby control the depth of the incision. In some embodiments, depth control is achieved through a specific mechanism, including a specific design for the length of the blade, a specific design for the slot height through which the blade is moving, the relative slot height as compared to the blade length, and control on the blade movement. For example, the handle itself or integrated stopper can be configured to enable the blade to penetrate to a certain depth in the slot and not further. By controlling the depth of the blade penetration, the depth of the incision to the target tissue can be configured to a wide range, for example, from 20 microns to 700 microns. In some embodiments this mechanism enabling blade protrusion or blade penetration or depth of incision is from 50 microns to 600 microns. In some embodiments this mechanism enabling blade protrusion or blade penetration or depth of incision is 100 microns to 500 microns. In some embodiments this mechanism enabling blade protrusion or blade penetration or depth of incision is 150 microns to 450 microns. In some embodiments this mechanism enabling blade protrusion or blade penetration or depth of incision is 200 microns to 400 microns. In some embodiments this mechanism enabling blade protrusion or blade penetration or depth of incision is 250 microns to 350 microns. In some embodiments this mechanism enabling blade protrusion or blade penetration or depth of incision is 300 microns to 325 microns. In some embodiments, the depth of incision is a fixed value falling within or corresponding to the end points of any of the aforementioned ranges. As used herein, “fixed” means that the depth cannot be adjusted by a user. In some embodiments, the depth of incision is adjustable by a user to any value falling within or corresponding to the end points of any of the aforementioned ranges.
Referring now to
In some embodiments, the blade B is placed within the horizontal slot 204 and moved across the horizontal slot 204 to make a horizontal cut in the sclera. In some embodiments, such a horizontal cut facilitates penetration of the blade B into the sclera when the blade B is placed within the blade entrance slot 202. In some embodiments, the blade B is placed into the blade entrance slot 202, as shown in
In some embodiments, the method continues by removing the blade B from the blade entrance slot 202, inserting the blade B into one of the vertical slots 206, sliding the blade B along the one of the vertical slots 206 to make a vertical cut (i.e., along one side of the scleral flap to be generated), and then repeating this process in the other one of the vertical slots 206 (i.e., along the other side of the scleral flap to be generated). At this point, the scleral flap has been formed, and the guidance device 100 can be removed from its place on the patient's eye. In other embodiments, while the horizontal cut through the horizontal slot 204 must be made first, the remaining cutting steps (i.e., the step of forming a tissue layer by moving the blade B within the blade entrance slot 202 and the step of making vertical cuts by moving the blade B within the vertical slots 206) may be reversed in sequence.
As discussed above, in some embodiments, a guidance device (e.g., the guidance device 100) includes a vacuum mechanism. In some embodiments, the vacuum mechanism includes the connector 102, the vacuum tube 210, and the suction slots 212. In some embodiments, the vacuum mechanism is activated prior to anchoring the guidance device 100 to the patient's eye. In some embodiments, vacuum mechanism anchors the guidance device 100 to the tissue of the patient's eye. In some embodiments, the vacuum mechanism eases the blade penetration of the blade B into the tissue of the patient's eye. In some embodiments, the vacuum mechanism (e.g., by the proximity of the suction slots 212 to the patient's eye) pulls the sclera upward due to the flexibility of the tissue of the sclera. In some embodiments, when the vacuum mechanism operates in this manner, the blade B can be inserted into the blade entrance slot 202 and into the sclera without the need to perform a horizontal cut (e.g., through the use of the horizontal slot 204 in the manner described above) first. In some embodiments, the vacuum mechanism attracts and stabilizes the portion of the sclera that is to form the scleral flap, thereby easing the cutting process and improving the uniformity of the resulting scleral flap.
In embodiments including a vacuum mechanism, the vacuum mechanism can include various types of mechanisms. In some embodiments, the vacuum mechanism includes a vacuum pump integrated into the handle 106 of the guidance device 100. In some embodiments, the vacuum mechanism includes a hollow tube within the handle 106 of the guidance device and between the connector 102 and the suction slots 212, and the connector 102 is configured to be coupled to an external vacuum pump. In some embodiments, the vacuum mechanism includes an auto-retractable syringe with a spring.
In some embodiments, hollow tubes extend through the handle 106 and head 104 of the guidance device 100 in order to convey the vacuum pressure to the desired location at the surface of the patient's eye. In some embodiments, the vacuum pressure to be applied at the source of the vacuum depends on the location of the source of the vacuum relative to the target area (i.e., the surface of the patient's eye). In some embodiments, the vacuum pressure generated by the vacuum mechanism is in a range between 100 and 700 mm Hg. In some embodiments, the vacuum mechanism is configurable by configuring a flow rate of a vacuum pump. In some embodiments in which a vacuum pump is integrated with the handle 106 of the guidance device 100, the flow rate of the vacuum pump is in the range between 0.3 liters per minute and 2.0 liters per minute. In some embodiments in which a vacuum pump is an external pump that is connected to the guidance device 100 via the connector 102, the flow rate of the vacuum pump is in the range between 30 liters per minute and 40 liters per minute. In some embodiments, the flow rate of the vacuum pump is between 0.3 liters per minute and 40 liters per minute.
As noted above, the exemplary guidance device 300 is substantially similar to the exemplary guidance device 100 other than insofar as the exemplary guidance device 300 lacks a vacuum arrangement. Accordingly, it will be apparent to those of skill in the art that a method for performing scleral flap practiced with the use of the exemplary guidance device 300 will be substantially similar to the method described above with reference to the exemplary guidance 100, save for the omission of the operation of the vacuum.
In some embodiments of the disclosure, the blade B is connected to a motor configured to move the blade B along a horizontal axis (i.e., parallel to the surface intended for cutting) to facilitate an easy cutting action. In some embodiments, a motorized handle enables the connection of the crescent blade unit generated for the purpose of this step in glaucoma operation. In some embodiments, a motorized blade B enables movement along the horizontal axis to a distance of between 50 microns and 200 microns to either side. In some embodiments, restriction of the degree of movement prevents excessive movement by a user (e.g., a surgeon), which can lead to complications. In some embodiments, all devices used in the methods described above are single-use. In some embodiments, a motorized handle is reusable and a blade is single-use.
In some embodiments, the shape and size of the generated scleral flap will be controlled by the design of the vertical and horizontal slots (e.g., the horizontal slot 204 and the vertical slots 206 of the guidance device 100), which define the frame of the generated flap.
In some embodiments, a guidance device includes an arc-shaped portion that is sized, shaped and positioned so as to assist a user in properly positioning the guidance device with respect to the eye. In some embodiments, the arc-shaped portion is sized, shaped and positioned so as to overlay the limbus line (i.e., the boundary between the cornea and the sclera) when the guidance device is properly positioned with respect to the eye.
In some embodiments, a guidance device includes a guidance element that is configured to be coupled to a handle portion at a rear of the guidance element. For example,
In some embodiments, a guidance device includes a horizontal slot configured for defining an initial incision within the eye (e.g., the horizontal slot 204 described above) and a blade entrance slot for separating a layer of the sclera having a desired thickness from the rest of the underlying sclera tissue (e.g., the blade entrance slot 202 described above), but lacks vertical slots. In some embodiments, such an incision may be referred to as a “groove” rather than as a “flap”. In some embodiments, such a cutting device may be suitable for use in cataract surgery, such as extracapsular cataract extraction (“ECCE”) or manual small incision cataract surgery (“MSICS”). In some such surgical procedures, the surgeon makes an incision in the sclera near the outer edge of the cornea (i.e., the limbus line). In some embodiments, the size of such an incision depends on whether the lens of the nucleus is to be removed whole or is to be broken into smaller pieces and removed by suction. In some such surgical procedures, the surgeon then enters the eye through the incision and opens the front of the capsule that holds the lens in place. However, in some surgical procedures such as ECCE and MSICS, no flap of the sclera is lifted, so no vertical cuts are made to define a liftable flap.
In some embodiments of a guidance device configured for use in surgical procedures such as ECCE and MSICS, the width of a groove (e.g., the length of a cut defined by a horizontal slot) is in a range between 5 mm and 11 mm. In some embodiments, the width of the groove depends on the specific surgical technique to be practiced (e.g., ECCE, MSICS, etc.). In some embodiments, the width of the groove depends on the preference of the surgeon. In some embodiments, a guidance device may be configured to facilitate the formation of a groove of a specific width (e.g., 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, etc.), and guidance devices may be made in a variety of configurations to provide a variety of options of widths.
In some embodiments of a guidance device configured for use in surgical procedures such as ECCE and MSICS, the depth of a groove (e.g, the location of a cut as defined by a blade entrance slot) is in a range of between ⅓ of the depth of the sclera and ½ of the depth of the sclera (e.g., in a range of 200 microns to 400 microns). In some embodiments, the depth of the groove depends on the specific surgical technique to be practiced (e.g., ECCE, MSICS, etc.). In some embodiments, the depth of the groove depends on the preference of the surgeon. In some embodiments, a guidance device may be configured to facilitate the formation of a groove of a specific depth (e.g., ⅓ of the depth of the sclera, ½ of the depth of the sclera, etc.), and guidance devices may be made in a variety of configurations to provide a variety of options of depths.
In some embodiments of a guidance device configured for use in surgical procedures such as ECCE and MSICS, the location of a groove (e.g., the location of a cut as defined by a horizontal slot) is in a range of 0 mm to 3 mm posterior of the limbus (wherein 0 mm posterior of the limbus means a cut positioned at the limbus). In some embodiments, the location of the groove depends on the specific surgical technique to be practiced (e.g., ECCE, MSICS, etc.). In some embodiments, the location of the groove depends on the preference of the surgeon. In some embodiments, a guidance device may be configured to facilitate the formation of a groove at a specific location (e.g., at the limbus, 1 mm posterior of the limbus, 2 mm posterior of the limbus, 3 mm posterior of the limbus, etc.), and guidance devices may be made in a variety of configurations to provide a variety of options of locations of cuts.
In some embodiments of a guidance device configured for use in surgical procedures such as ECCE and MSICS, the guidance device is configured so as to guide the formation of a groove into the anterior chamber of the eye. In some embodiments, the guidance device is configured so as to guide the formation of a groove that is wider in the cornea than at the scleral opening, by using a long length blade entering through the slot 902 with the guidance element being configured not to limit movement of the blade in the anterior direction.
In some embodiments, the present disclosure relates to a kit comprising the guidance device and one or more surgical knives. In some embodiments, the one or more surgical knives comprise two separate knives each with a single blade. In some embodiments, the single blades are the same. In some embodiments, the single blades are different. In some embodiments, the one or more surgical knives can comprise a single double-ended surgical knife. For example,
While a number of embodiments of the present disclosure have been described, it is understood that these embodiments are illustrative only, and not restrictive, and that many modifications may become apparent to those of ordinary skill in the art. For example, all dimensions discussed herein are provided as examples only, and are intended to be illustrative and not restrictive.
This application claims the priority of U.S. provisional application Ser. No. 62/745,155, filed Oct. 12, 2018, which is incorporated herein by reference in its entirety for all purposes.
Number | Date | Country | |
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62745155 | Oct 2018 | US |