Patent Publication Number: US-2013245634-A1

Title: Plunger system for intraocular lens surgery

Description:
RELATED APPLICATIONS 
     This application claims priority to U.S. provisional application Ser. No. 61/579,887, filed on Dec. 23, 2011, the contents which are incorporated herein by reference. 
    
    
     BACKGROUND 
     The present invention relates to optical surgery, and more specifically to surgical replacement of a patient&#39;s lens. 
     The human eye, in simple terms, functions to provide vision by transmitting and refracting light through a clear outer portion called the cornea and focusing the image by way of the lens onto the retina at the back of the eye. The quality of the focused image depends on many factors including the size, shape, and length of the eye, and the shape and transparency of the cornea and lens. 
     When trauma, age, or disease causes the lens to become less transparent, vision deteriorates because of a reduction in light transmitted to the retina. This deficiency in the eye&#39;s lens is medically known as a cataract. The treatment for this condition is often surgical removal of the lens and implantation of an artificial lens, often termed an intraocular lens (IOL). 
     An IOL is often foldable and inserted into the eye through a relatively small incision by being advanced through an IOL insertion cartridge, which causes the IOL to fold. The IOL is typically advanced through the insertion cartridge by a plunger-like device. 
     BRIEF SUMMARY 
     In one general implementation, a system for intraocular lens (IOL) surgery may include a body and a plunger. The body may include an outer wall and an inner wall, with the inner wall defining a passage through the body and including a first guide member. The plunger may be adapted to move within the passage and include a first end, a second end, and a second guide member. The first end may be adapted to be engaged by a user for moving the plunger within the passage, and the second end may include a tip adapted to interface with an intraocular lens and having an asymmetric (e.g., rectangular) cross-section. The second guide member may interact with the first guide member to rotate the tip when the plunger is moved through the body. The rotation of the tip may, for example, be approximately 90 degrees as the plunger is advanced relative to the body. 
     In certain implementations, the first guide member may be a protuberance that extends into the passage, and the second guide member may be a channel adapted to receive the protuberance. In some implementations, the first guide member may be a ramped surface, and the second guide member may be a protuberance that extends into the passage and is adapted to following the ramped surface. 
     Various implementations may include one or more features. For example, by having a rotating plunger tip, a system for intraocular lens surgery may allow a plunger to have adequate height at initial contact with the IOL, which can facilitate lens folding, while having reduced height when arriving at the insertion point, which can facilitate using smaller incisions. As another example, the rotation function may occur and be controlled automatically, with no end user action required. Thus, repeatable results may be obtained. 
     The details and features of various implementations will be conveyed by the following description, along with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIGS. 1A-B  show an example plunger system for intraocular lens surgery. 
         FIG. 2  is a cross-sectional view of an example IOL interface of an example plunger. 
         FIG. 3  is a partial cross-sectional view of an end of an example plunger having a rotatable annular ring. 
         FIG. 4  shows a cross-sectional view of another example plunger system. 
         FIGS. 5A and 5B  are partial detail views of another example plunger guide system. 
         FIGS. 6 and 7  show front and side views of an example plunger. 
         FIG. 8A and 8B  are perspective views of an example intraocular lens insertion cartridge. 
         FIGS. 9A and 9B  are cross-sectional views of an example plunger guide system. 
         FIG. 10  is a flowchart illustrating an example process for intraocular lens surgery. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1A and 1B  illustrate an example plunger system  100  for intraocular lens (IOL) surgery. Plunger system  100  includes a shell  110  and a plunger  120 , which is adapted to move within shell  110 . 
     Shell  110  includes a body  112  that has a passage  114  therethrough. As illustrated, body  112  is generally cylindrical in shape, and so is passage  114 . Shell  110  also includes an annular ring  116  that extends from body  112 . Annular ring  116  may be sized to allow a user, such as a physician or other medical professional, to manually grasp the system  100  (e.g., with a pair of fingers). Shell  110  may be made of plastic, metal, or any other appropriate material. 
     Plunger  120  includes a body  121  and has a first end  122   a  and a second end  122   b . As illustrated, first end  122   a  is generally cylindrical and sized to fit inside passage  114  while still allowing plunger  120  to move relative thereto. Second end  122   b  is opposite first end  122   a  and includes an IOL interface  124 . As shown in the illustrated example, IOL interface  124  may have a rectangular cross-section. IOL interface  124  may have other cross-sectional shapes in other implementations. For example, in some instances, the IOL interface  124  may have an oval or elliptical cross-section. However, the IOL interface  124  may have other suitable cross-sections. Also, in some implementations, IOL interface  124  may be approximately 2-3 mm in width. Further, in some implementations, the IOL interface  124  may be integrally formed on the body  121 . In other implementations, IOL interface  124  may not be an integral with the body  121 . For example, IOL interface  124  may be a separate component that is coupled to the body  121 . 
     IOL interface  124  is operable to interface with an IOL and to advance the IOL through an IOL insertion cartridge. IOL interface  124  may be made of an injection-molded elastomer, polymer (e.g., polypropylene or styrene), metal, or any other appropriate material. 
       FIG. 2  shows a cross-sectional view of an example IOL interface  124 . The illustrated example IOL  124  interface includes a rectangular cross-section having a width  200  and a height  202 . In some implementations, one cross-sectional dimension of the IOL interface  124  may be greater than another cross-sectional dimension. For example, in some instances, a first dimension of the IOL interface cross-section may be twenty percent greater in size than a second cross-sectional dimension. Thus, again referring to  FIG. 2 , in some instances, the width  200  may be twenty percent greater than the height  202 . In some instances, the size of one cross-sectional dimension may be more than twenty percent larger than the second cross-sectional dimension. For example, in some instances, the size of one cross-sectional dimension may be twice the size of another cross-sectional dimension. Thus, in some instances, the width  200  may be up to two times the size of the height  202 . Thus, it is within the scope of the present disclosure that a size of a first cross-sectional dimension of an IOL interface, such as IOL interface  124 , may be within the range of twenty percent larger to two times the size of a second cross-sectional dimension of the IOL interface. In other instances, one cross-sectional dimension may be greater than two times the size of a second cross-sectional dimension. Further, although the description is made with reference to an example IOL interface having the rectangular cross-sectional shape shown in  FIG. 2 , the scope is not so limited. Rather, the relative sizes of the cross-sectional dimensions also apply to IOL interfaces having other cross-sectional shapes. 
     First end  122   a  may generally taper to the shape of IOL interface  124 , or there may be a distinct transition from the shape of first end  122   a  to the shape of IOL interface  124 . Thus, the manner in which the first end  122   a  transitions into the shape of IOL interface  124  may be in any suitable manner. Plunger  120  may be made of plastic, metal, or any other appropriate material. 
     Plunger  120  may also include an annular ring  126  that extends from body  121  at end  122   a.  Annular ring  126  may assist a user in manipulating plunger  120  to advance it through shell  110 . In some instances, the annular ring  126  may be rotatably attached to the body  121 . For example, as shown in  FIG. 3 , a protrusion  300  formed on the plunger body  121  is received into a recess  302  formed in the annular ring  126 . Thus, the annular ring  126  is retained on and freely rotatable relative to the plunger body  121 . In other instances, a protrusion formed on the annular ring  126  may be received into a recess or opening formed in the body  121  so that the annular ring  126  is rotatable relative to the body  121 . However, other ways of rotatably coupling the annular ring  126  to the body  121  may be used and are within the scope of the disclosure. 
     Rotatably coupling the annular ring  126  and body  121  is advantageous because, a user may utilize a finger, such as a thumb, to apply pressure to the plunger  120  during use. As the plunger  120  moves relative to the shell  110 , the plunger  120  rotates relative thereto, as discussed in more detail below. If the annular ring  126  is rotatable relative to the body  121 , the user&#39;s thumb does not move relative to the annular ring  126  as the plunger body  121  rotates relative to the shell  110 . This improves control of the plunger  120  and, hence, the plunger system  100 , during use. 
     Shell  110  and plunger  120  may include guide members that rotate plunger  120  relative to shell  110  as plunger  120  moves therethrough. For example, the guide members may be a protrusion received into a groove.  FIG. 4  shows a cross-sectional view of an example plunger system  400 . In the illustrated example, shell  410  includes a protrusion  412  received into a groove  414  of plunger  420 . Thus, in some implementations, a protrusion maybe on the shell, such as shell  110  or  410 , while the groove may be in the plunger, such as plunger  120  or  420 . In other implementations, the protrusion may form part of the plunger and be received into a groove formed in the shell 
       FIG. 5  shows a partial detail view of example plunger system  500  in a disassembled configuration. As shown, plunger  520  includes a protrusion  512  extending from an exterior surface  513  of the plunger  520 . Shell  510  includes a groove  514  formed in an inner wall  516  of the shell  510 . The groove  514  is adapted to receive the protrusion  512 . The shell  510  also defines a passage  518  adapted to receive the plunger  520 . Similar to the examples described above in which the protrusion forms part of the shell and the groove is formed in the plunger, the protrusion  512  and groove  514  cooperatively interact to rotate the plunger  520  as the plunger  520  is displaced within the shell  510 . 
     In operation, before plunger  120  is moved through passage  114 , IOL interface  124  is in a first orientation, as depicted in  FIG. 1A . This orientation may, for example, be beneficial for engaging an IOL, which may be in an IOL insertion cartridge. As plunger  120  is moved through passage  114 , the IOL interface  124  advances an IOL through the IOL insertion cartridge, such as IOL insertion cartridge  800  shown in  FIGS. 8A and 8B . As the IOL interface  124  reaches a desired location within the IOL insertion cartridge, interaction between the protrusion and the groove (which may be similar to those shown in  FIGS. 4 ,  5 ,  9 A, or  9 B, for example) causes the plunger  120  to rotate about its longitudinal axis  130  to a different orientation, as depicted in  FIG. 1B . In particular implementations, the difference between the beginning orientation and the ending orientation may be approximately 90 degrees. Plunger  120  may then advance the IOL through the end of the IOL insertion cartridge. 
       FIGS. 6 and 7  show side and top views, respectively, of an example plunger  620 . The plunger  620  includes a groove  614  and an IOL interface  624 . In the example shown, the groove  614  includes a curved portion  616 . The curved portion  616  is operable to rotate the plunger  620  a desired amount. In the illustrated example, the curved portion  616  is operable to rotate the plunger  620  approximately 90 degrees as it is advanced through a shell as a result of interaction between the groove  614  and a protrusion of the shell received therein. In other instances, the amount of rotation of the plunger relative to the shell as a result of interaction between the groove and protrusion during advancement of the plunger through the shell may be greater or less than 90 degrees. 
       FIGS. 6 and 7  show that the cross-sectional shape of the groove  614  has a generally rectangular shape. However, in other instances, the groove  614  may have other shapes. For example, the groove  614  may have a rounded shape, a semi-circular shape, a v-shape, a square shape, or any other desired shape. 
     Further, as illustrated by  FIGS. 6 and 7 , the curved portion  616  forms a portion of the total length of groove  614 . A length of the curved portion  616  relative to a total length of the groove  614  may be selected to be any desired amount. Thus, in some implementations, the curved portion  616  may form only a small portion of the overall length of the groove  614 . In such instances, the IOL interface  624  is made to rotate a desired amount over a short distance, resulting in a rapid rotation of the IOL interface  624  for a particular rate of displacement of the plunger  120 . In other implementations, the length of the curved portion  616  may form a larger portion of the total length of the groove  614 . Consequently, rotation of the IOL interface  624  may be more gradual as the plunger  620  is advanced through the corresponding shell, such as shell  110 ,  410 , or  510 , for example, at the particular rate of displacement. As such, not only may the amount by which the IOL interface is rotated relative to the shell be varied, the amount of rotation of the IOL interface per axial displacement of the plunger within the shell may also be varied. 
       FIGS. 8A and 8B  illustrate an example IOL insertion cartridge  800 . IOL insertion cartridge  800  facilitates the insertion of an IOL into a patient&#39;s eye. IOL insertion cartridge  800  includes a body  812  that has ends  813   a  and  813   b  and a passage  814  through the body. During surgery, a foldable IOL, which may be made of silicone, soft acrylics, hydrogels, or other appropriate materials, is moved through passage  814  in preparation for insertion into the eye. IOL insertion cartridge  800  also includes sides  816   a  and  816   b , which assist in grasping the IOL insertion cartridge. Sides  816   a  and  816   b  taper outward to form wings  817 , which also assist in grasping the IOL insertion cartridge. 
     As shown, passage  814  has an asymmetric bore at end  813   a,  which assists in folding an IOL. A common IOL may be approximately 6 mm in diameter, and with haptics can be up to around 13 mm. However, surgical incisions are typically much smaller (e.g., 2-3 mm in width). An IOL is therefore typically folded before insertion through the incision. Passage  814  also tapers along its length to an elliptical bore at end  813   b  to assist in folding an IOL. Thus, as an IOL is advanced through passage  814 , the IOL is folded due to the shape of the passage. The end of the passage may be the injection point through which the lens is inserted into an eye. 
     In certain implementations, IOL insertion cartridge  800  may be molded as a single piece from any suitable thermoplastic, such as polypropylene. In particular implementations, the thermoplastic may contain a lubricity enhancing agent. 
     Although  FIGS. 8A ,  8 B illustrate one example implementation of an IOL insertion cartridge, other implementations may include fewer, additional, and/or a different arrangement of components. In some implementations, for example, body  810  may not include wings  817 . Additionally, passage  814  may have a symmetrical bore (e.g., round or elliptical). 
     System  100  is generally usable with pre-loaded and manually loaded IOL insertion cartridges with substantially oval or elliptically nozzle tip shapes where the nozzle tip height is smaller than the nozzle tip width. Shapes of this type are typical of many delivery systems due to their compatibility with the incision. 
     System  100  provides a variety of features. For example, system  100  allows a plunger to have adequate height at initial contact with the IOL, which can facilitate lens folding, while having reduced height when arriving at the insertion point, which can facilitate using smaller incisions. This is accomplished by the ability of the plunger, and particularly the IOL interface, to rotate during translation through the IOL insertion cartridge. This rotation provides for improved folding of the IOL as well improved delivery of the IOL through a small nozzle tip. 
     Typically, with one piece plungers, dimensional compromises have to be made to arrive at a best-fit plunger height that adequately accomplishes the lens folding and delivery tasks and still fits through a small nozzle tip. The disadvantage to this approach is that the plunger is often not tall enough initially to provide functional performance under extreme delivery conditions and not small enough to provide as much clearance in the nozzle tip as is preferred. Very tight tolerances are also required for plungers of this design, which increase initial development and manufacturing costs. Moreover, tight control of manufacturing processes over time is also required in order to maintain the product dimensional specifications. Thus, system  100  provides a one-piece plunger component which reduces initial design and manufacturing complexity. Moreover, the functions of system  100  are designed to occur and be controlled automatically, with no end user action required. 
     Although  FIGS. 1A and 1B  illustrate one implementation of a plunger system for IOL surgery, other implementations may include fewer, additional, and/or a different arrangement of components. For example, a plunger system may not include annular ring  116  or annular ring  126 . As another example, body  121  may not be a cylinder. For instance, body  121  could have a “plus-shaped” cross-section composed of two intersecting webs. As a further example, IOL interface  124  may not be rectangular in cross section. For example, in some instances, IOL interface  124  may have an elliptical or oval cross-sectional shape. However, the body  121  of the plunger  120  may have any suitable shape such that the plunger  120  is operable to rotate within the shell  110  as described herein. 
       FIGS. 9A and 9B  illustrate another example plunger system  900 . As illustrated, system  900  includes a shell  910  and a plunger  920 .  FIG. 9A  illustrates a cross section of shell  910  and plunger  920  at a location of the plunger  920  having a protrusion  916 .  FIG. 9A  represents a cross section at a first point during operation of the system  900 .  FIG. 9B  illustrates a cross section of shell  910  and plunger  920  the location of the plunger  920  having the protrusion  916  at a subsequent point during operation of the system  900 . 
     Shell  910  includes an outer wall  913  and an inner wall  915 . Inner wall  913  defines a passage  914 . Also, a groove  924  is formed in the inner wall  913 . The protrusion  916  is received within the groove  924 . While  FIGS. 9A ,  9 B illustrate the groove  924  as formed in the shell  910  and the protrusion  916  formed on the plunger  920 , as explained above, this configuration may be switched. That is, the groove may be formed in the plunger, and the protrusion may be formed on the inner surface of the shell. As also explained above, groove  924  may have any shape operable to alter the rotational orientation of plunger  920  as it is moved through shell  910 . 
     In certain modes of operation, groove  924  engages protrusion  916  as plunger  920  is advanced through passage  914 , as illustrated in  FIG. 9A . As plunger  920  is advanced further along passage  914 , interaction between protrusion  916  and groove  924  causes plunger  920  to rotate counterclockwise. However, in other implementations, plunger  920  may be rotated clockwise. As illustrated, protrusion  916  remains engaged with groove  924  to define an orientation of the plunger  920  relative to the shell  910 . 
     In the illustrated example, the plunger  920  is rotated approximately 90 degrees as a result of interaction between the groove  924  and the protrusion  916 . However, as explained above, the amount of rotation of the plunger  920  relative to the shell  910  may be selected to be any desired amount. Further, while a cooperating groove and protrusion configuration is illustrated, the scope of the disclosure is not so limited. Rather, any cooperating features operable to rotate the plunger and shell relative to each other as the plunger is axially translated through the shell may be used. 
       FIG. 10  illustrates an example process  1000  for using a plunger system for intraocular lens surgery. Process  1000  may, for instance, be performed using a plunger system. For example, the process  1000  may be performed using one or more of the example plunger system described herein. 
     Process  1000  includes positioning an IOL in an IOL insertion cartridge (operation  1004 ). The IOL insertion cartridge may, for example, be similar to IOL insertion cartridge  800 . 
     Process  1000  also includes engaging a plunger of a plunger system with the IOL (operation  1008 ). The plunger may, for example, be engaged with the IOL by advancing the tip of the plunger until it touches the IOL. 
     Process  1000  also includes advancing the IOL relative to the IOL insertion cartridge using the plunger (operation  1012 ). For example, the plunger may be advanced relative to the shell of the plunger system, which may move the IOL in the IOL insertion cartridge. The IOL may be folded by advancement through the IOL insertion cartridge. 
     As the IOL is moved relative to the IOL insertion cartridge, the plunger rotates (operation  1016 ). In particular implementations, the plunger may rotate approximately 90 degrees due a guide system arrangement (e.g., a groove and protrusion arrangement) of the plunger system. However, the plunger may be rotated any desired amount. 
     Process  1000  also includes further advancing the IOL relative to the IOL insertion cartridge using the plunger (operation  1020 ). The additional advancement may further fold the IOL. 
     Additionally, process  1000  includes injecting the IOL into an eye (operation  1024 ). For example, the IOL may be injected when it reaches the end of the IOL insertion cartridge. 
     Although process  1000  illustrates one example of a process for using a plunger system for intraocular lens surgery, other processes for using a plunger system for IOL surgery may include fewer, additional, and/or a different arrangement of operations. For example, a process may not include positioning the IOL in the IOL insertion cartridge. The IOL may, for instance, have been pre-positioned in the IOL insertion cartridge. As another example, a process may call for engaging the plunger system with the IOL insertion cartridge. 
     The various implementations discussed and mentioned herein have been used for illustrative purposes only. The implementations were chosen and described in order to explain the principles of the disclosure and the practical application and to allow those of ordinary skill in the art to understand the disclosure for various implementations with various modifications as are suited to the particular use contemplated. Thus, the actual physical configuration of components may vary. For example, the mentioned size(s) of components and their illustrated sizing relative to each other may vary based on application. Moreover, the shapes of one or more components may vary depending on application. Thus, the illustrative implementations should not be construed as defining the only physical size, shape, and relationship of components. 
     The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting. As used herein, the singular form “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in the this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups therefore. 
     The corresponding structure, materials, acts, and equivalents of all means or steps plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present implementations has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the implementations in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. 
     A number of implementations have been described for a plunger system for intraocular lens surgery, and several others have been mentioned or suggested. Moreover, those skilled in the art will readily recognize that a variety of additions, deletions, modifications, and substitutions may be made to these implementations while still providing a plunger system for intraocular lens surgery. Thus, the scope of the protected subject matter should be judged based on the following claims, which may capture one or more concepts of one or more implementations.