Abstract:
An orbital implant device is provided. The orbital implant device comprises a frame, defining a plurality of openings, a plurality of flexible sections coupled to said frame, said frame and said plurality of flexible sections defining a volume, and at least one injection port for inflating and delating the said volume.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to an orbital implant device for eye replacement after enucleation and, more particularly, to an adjustable orbital implant device for conforming to an eye socket. 
     Enucleation is the removal of the globe from the eye socket. The most common indications for enucleation are intraocular malignancy, blind painful eye, prevention of sympathetic ophthalmia and trauma. The enucleation procedure involves the separation of all connections between the globe and the patient so that the globe can be removed. 
     Implants are used to replace the volume lost by the enucleation procedure. There are two major types of buried implants. The first and most simple are the nonintegrated implants. These implants lack any structure for attachment to the extraocular muscles and do not allow for ingrowth of organic tissue. This type of implant is typically formed of glass, rubber, silicone, steel, gold, silver, polymethylmethacrylate, or the like. The second type of implant is the integrated implant. These implants allow attachment of extraocular muscles, tissue ingrowth, and direct attachment of an ocular prosthesis. 
     While enucleation can be performed without implant placement, this is not preferred for several reasons. For example, if the volume is not replaced, the enucleation will result in a poor cosmetic result. This will only increase the psychological issues that a patient will have to deal with in this already difficult situation. Therefore, it is recommended that an implant be utilized during the enucleation procedure. 
     When a prosthesis is going to be used after an enucleation, it is important to have a well-fitting implant. Many problems associated with the use of an implant are caused by inadequate volume replacement. Therefore, an adjustable orbital implant is desirous. 
     One type of orbital implant utilizes a single balloon attached at a rear portion of an orbital implant. The balloon can then be inflated to increase the surface area of the implant. However, this implant only allows for an increase of the surface area of the implant at one point on the implant. Additionally, this implant does not allow for differential expansile qualities at various points on the implant. Furthermore, by using a single balloon to increase the surface area of the implant, the rectus muscles will also become stretched when the balloon is inflated. 
     Therefore, an orbital implant device is needed that will allow surface area adjustments at multiple points on the implant without stretching the rectus muscles and that will accommodate differential expansile qualities at various locations on the orbital implant device. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an orbital implant device that allows expansion of the surface area of the device at more than one point. 
     It is an object of the present invention to provide an orbital implant device that allows for differential expansile qualities at various positions on the device. 
     It is a further object of the invention to provide an orbital implant device that allows for the attachment of rectus muscles thereto without significant stretching of the rectus muscles when the surface area of the device is increased. 
     It is a further object of the present invention to allow an increase or a decrease in the size of the orbital implant through the addition or removal of a fluid media. 
     In accordance with these and other objects, advantages and novel features of the invention evident from the following description of the preferred embodiment of the invention, an adjustable orbital implant is provided having an outer surface comprising a sphere-defining frame presenting a plurality of openings, a plurality of flexible sections received within said plurality of openings, coupled with said frame, and at least one injection port for the addition and withdrawal of an amount of a fluid media in at least one of said plurality of flexible sections, whereby said flexible sections can be expanded and contracted to vary the size of the orbital implant. 
     By providing an orbital implant device in accordance with the present invention, numerous advantages are realized. For example, the orbital implant device of the present invention allows for differential expansile qualities at various positions on the orbital implant device. By employing the properties of differential expansile qualities, a doctor will have substantially more control over the shape and size of the orbital implant such that they will be able to conform the orbital implant to fit precisely within the volume created by the enucleation procedure. In addition, the doctor will be able to expand or contract the size of the orbital implant throughout the life of the orbital implant, thereby eliminating the need for replacement of an implant that no longer conforms to a patient&#39;s eye socket. 
     Another feature of the present invention resides in the orbital implant&#39;s ability to be expanded and contracted at various points over most of the surface of the device without stretching the rectus muscles. Specifically, this device permits the attachment of the rectus muscles to the orbital implant while allowing for expansion and/or contraction of the orbital implant without readjustment of the rectus muscles because they are attached to a portion of the device that remains static during expansion and contraction. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
     A preferred embodiment of the present invention is described in detail in the accompanying drawings, which form part of the specification, and are to be read in conjunction therewith, and in which like reference numerals are used to indicate like parts in the various views: 
     FIG. 1 is a perspective view of an orbital implant device of the present invention; 
     FIG. 2 is a partial exploded view of an orbital implant device of the present invention; 
     FIG. 3 is a cross-sectional view taken across line  3  of FIG. 2; 
     FIG. 4 is a cross-sectional view taken across line  4  of FIG.3; 
     FIG. 5 is a perspective view of the implant device of the present invention after differential expansion; and 
     FIG. 6 is an exploded view of an orbital implant device of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring generally to FIGS. 1 and 2, an orbital implant device employing the principles ofthe present invention is broadly designated in the drawings and is indicated by reference numeral  10 . The preferred embodiment of the present invention includes a frame comprising first and second arcuate bands  12 , and a central support member  14 . The first and second arcuate bands  12  define a plurality of openings on the surface of the orbital implant device  10 . As can be seen in FIG. 1, these openings are substantially covered or filled by four independent expandable quadrant sections  16 . As is consistent with the present invention, the orbital implant  10  is designed to fill the void created by enucleation. 
     More specifically, the frame comprises a first arcuate band  12  extending approximately 360 degrees around a central point, and a second arcuate band  12 , also extending around the same point approximately 360 degrees, the first band being removed approximately 90 degrees from the second arcuate band so that the bands extend in substantially perpendicular planes to define a hollow sphere shape divided into four approximately equal quadrants. Each band  12  includes a groove  18  on an outer surface positioned at approximately the midpoint of the band and extending approximately the length of the bands  12 . The bands  12  are integral with the central support member  14 . The support member extends through the center of the hollow sphere defined by the bands and is coupled at each end to bands  12 . The support member is cylindrical in shape and includes a bore  14   a  which extends inwardly from an open end  14   b.  The central support member defines four passages  14   c  extending radially from bore  14   a  through an exterior surface of the support member. Each of the four passages  14   c  are separated by a baffle  26 . The passages are located in a circular pattern and spaced approximately 90 degrees from one another. The open end of bore  14   a  is coupled to a self-sealing membrane  20  which is adhesively secured to the central support member  14 . The self-sealing membrane has an arcuate outer surface that protrudes beyond the surface of the sphere defined by bands  12 . 
     Quadrant sections  16  have an arcuate upper surface and a concave lower surface connected by two planer side walls. The upper surface area is shaped to cover the exposed quadrant section defined by the arcuate bands  12 . The side walls extend inward from the upper surface and taper toward the lower concave surface. The concave lower surface is coupled to the outer surface of the central support member  14 . The concave lower surface defines a centrally located opening  22  that extends into a fluid tight volume defined by the upper surface, the lower surface and the side walls of the quadrant sections  16 . The openings in quadrant sections  16  are aligned with and in fluid communication with passages  14   c  located on the central support member  14 . Each one of quadrant sections  16  can have different expansile qualities. 
     In use, an orbital implant device  10  of the present invention is selected by the doctor that will substantially fill the volume remaining after an enucleation procedure. As discussed above, the frame of the device comprises the first and second arcuate bands  12  supported by the central support member  14 . In the preferred embodiment, these frame pieces are formed of a flexible material having memory characteristics that allow the device to be deformed to the extent necessary to allow insertion into the void remaining after enucleation. While the frame material is deformable by the doctor for insertion, after it has regained its original shape within the eye socket, it is not deformable under the normal pressures exerted within the socket. The frame can thus be formed of any type of material that is safe for use within the human body and that is either rigid or deformable with memory characteristics. Specifically, the memory characteristics allow the deformed frame to return to its original shape after insertion into the eye socket. The frame can be formed of any approved substance. Preferably, the frame can be formed of silicone or polymethylmethacrylate. However, the frame can also be formed of any rigid porous material such as hydroxyapatite or MEDPOR®. 
     After the doctor has placed it into the eye socket, he/she will either wait until the frame has regained its original shape or partially inflate the device. After the device has regained its original shape, the doctor will couple the rectus muscles to the device in the grooves  18  on the arcuate bands  12 . This is accomplished by tying the rectus muscles around the orbital implant in grooves  18 . As discussed above, the pressure exerted on the arcuate bands  12  by the rectus muscles is insufficient to deform the shape of the frame. By attaching the rectus muscles around or directly to the orbital implant, the implant is allowed to move in a fashion similar to a normally functioning eyeball. 
     After the attachment of the rectus muscles to the orbital implant device, the size of the orbital implant is adjusted to secure the device into the desired volume remaining after the enucleation procedure. The size or surface area of the device can be adjusted through use of the expandable quadrant sections  16  which are formed of a flexible material. The flexible material can be any material that is flexible and safe for use in the human body. In the preferred embodiment, the expandable quadrant sections  16  are formed of silicone. In the preferred embodiment the quadrant sections are puncture resistant. To expand the surface area of the device, a fluid media is used to fill the expandable quadrant sections. The fluid media can be any gas or liquid that is safe for use in the human body. It is preferred that the fluid media be lighter than tissue so that the implant can more freely move within the eye socket. While the media can be either a gas or a liquid, in the preferred embodiment, the media utilized is saline solution. 
     To expand the surface area of the device by filling sections  16  with the fluid media, the doctor will insert a first needle through the self-sealing membrane  20  into the bore  14   a.  In the preferred embodiment, the self-sealing membrane  20  protrudes beyond the sphere defined by the bands  12  such that the doctor can palpate the implant to find the membrane  20 . This reduces the chances of accidentally puncturing one of the quadrant sections  16 . One skilled in the art will appreciate that other structures can be utilized for locating the self-sealing membrane  20 . The needle will allow pressure to escape the device as the fluid media is added. The doctor will then insert a second needle of a syringe and needle apparatus  24  which contains the media to be inserted into the device. As best illustrated in FIGS. 3,  4  and  6 , when the syringe  24  is depressed by the doctor, the media travels through the self-sealing membrane  20  into the bore  14   a  defined by the central support member  14 . The media then moves through the passages  14   c  into the expandable quadrant sections  16 . The media is forced into the sections  16 , they expand to increase the surface area of the device. This expansion fills the volume remaining after the enucleation procedure. When the device is expanded to the appropriate size, the doctor will remove the first needle and then the second needle attached to the syringe  24 . Because the membrane  20  is self-sealing, when the needles are removed the device will maintain the expanded size. 
     In certain circumstances the doctor may determine that the expandable quadrant sections  16  may need to be of varying sizes. As best seen in FIG. 5, the present invention allows the doctor to select sections  16  with different expansile qualities. These different expansile qualities can be achieved by selecting sections  16  formed of different thicknesses. Additionally, not only can the thickness of the sections  16  be changed at each one of the four positions on the device, but the sections  16  can be formed of different materials. Thus, the device can preferentially expand to a greater size in a given direction than in the other remaining directions. This gives the doctor more control for ensuring that the device expands properly within the volume of a patient&#39;s eye socket. In addition to changing the expansile qualities of the individual quadrant sections to regulate their size, the central support member  14  can be designed to include a baffle  26  so that the doctor can selectively add a fluid media to each quadrant section independently of the remaining quadrant section. The baffle  26  defines a passageway for directing the fluid media into individual quadrant sections. 
     In a second embodiment, the expandable quadrant sections  16  are formed of a planar flexible material coupled to the first and second arcuate bands  12 . This embodiment functions in the same way as the previous embodiment in that the doctor will insert a first needle through the self-sealing membrane  20  into the bore  14   a.  This needle will allow air to escape the device as the media is added. The doctor will then insert a second needle that is attached to a syringe  24  containing the media to be inserted into the device. When the syringe is depressed by the doctor, the media travels through the self-sealing membrane  20  into the bore  14   a  defined by the central support member  14 . The media then moves through the passages  14   c  into a sealed space defined by the planar flexible material and the first and second arcuate bands  12 . As the media is forced into the sections  16 , the sections  16  expand to increase the surface area of the device to fill the volume remaining after the enucleation procedure. When the device is inflated to the appropriate size, the doctor will remove the first needle and then the second needle. Because the membrane  20  is self-sealing, when the needles are removed the device will maintain the size selected by the doctor. This embodiment also allows the doctor to control the size of each the four sections by selecting the thickness of the planar material used or the type of material used for each section. 
     While the above procedures describe the addition of a media into the device, it is envisioned that there will be instances when the media will need to be removed from the device. For example, if the device needs to be removed, a doctor will simply insert a needle through the membrane  20  and remove an amount of media necessary for removal of the device. 
     In addition to the above-described device, the present invention includes a method of utilizing the device. Specifically, the method includes providing an adjustable orbital implant device consistent with the present invention. The device is then collapsed so that the device will fit into a void remaining after an enucleation procedure. After the device has been inserted and has regained its original shape within the void, the rectus muscles are coupled to the device. The size of the device is than adjusted to conform to the individual patient&#39;s eye socket. 
     The process of expanding and contracting the orbital implant, as described above, can be performed throughout the life of the orbital implant. This is important because oftentimes atrophy takes place in the eye socket over time. As the atrophy decreases the size of the eye socket, a doctor can increase the size of the device as outlined above. This avoids having to replace the device due to atrophy. In addition to atrophy, this device is useful for children because, as they grow and the eye socket grows, the size of the device can be increased to fill the eye socket without replacement. 
     Although the invention has been described with reference to the preferred embodiment illustrated in the drawing figures, it is understood that equivalence may be employed and substitutions made therein without departing from the scope of the invention as recited in the claims. 
     From the foregoing, it has been seen that this invention is one well-adapted to attain all of the ends and objects hereinabove set forth together with other advantages which are obvious and which are inherent to the structure of the present invention. It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims. 
     It is further understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.