Abstract:
The present invention relates generally to a medical device, and more particularly to an ophthalmic surgical device for extracting an intra-ocular lens implant.

Description:
RELATED APPLICATION  
       [0001]    This application claims the benefit of U.S. Provisional Application No. 60/294,065, filed on Sep. 7, 2001, which is incorporated here in its entirety. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates generally to a medical device, and more particularly to an ophthalmic surgical device for extracting an intra-ocular lens implant.  
         BACKGROUND OF THE INVENTION  
         [0003]    In the United States there are 1,500,000 cataract extractions a year, making this procedure one of the most commonly performed surgery. The complication rate is believed to be about 2%, which would be 30,000 cases a year of an intraocular mishap. There is probably a 20% incidence in this group of complications that are repairable by removing and replacing the intra-ocular lens implant (implant). This necessitates the removal of approximately 6,000 implants a year with no standardized systems or management organization to remove these lenses.  
           [0004]    Cataracts are the leading cause of blindness in the world. The clouding of the human lens causes cataracts. In reality the human lens yellows and becomes less clear with age, when it clouds it is called a cataract. The cataract is somewhat akin to water that appears clear until it goes over a waterfall and appears white to the observer. In fact the word cataract is derived from the same Greek root for the name of a waterfall or cataract.  
           [0005]    The human lens is responsible for focusing the images on the back of the eye that are in the gaze of the eye. The human eye is somewhat analogous to a simple film camera. There are some lenses that focus the light at the front of the camera as in the eye. This focusing the light on the film or in the case of the eye the retina, which is a neurosensory membrane, that converts the optical image into neurological electrical activity that is transmitted to the vision center of the brain. If one thinks of the eye as a video camera that has a chip (retina) that converts the image to electrical activity and send it to the monitor which in the eye&#39;s case is the occipital lobe of the brain.  
           [0006]    Cataract extraction results from removing the cloudy lens from the eye. This also causes the eye to loose its ability to focus light on the retina unless it is replaced. In days gone by the elderly cataract patient was relegated to a handicapped life only being able to see with extremely thick aphakic (no lens) glasses. In the recent past, patients had to spend 2 weeks in the hospital with sand bags around their head and never returned to a fully active life again due to the distortion of these glasses and the magnification and distortion issues, even with contact lenses.  
           [0007]    In the last 20 years this has all been changed because the human lens is now replaced with a plastic intra-ocular implant. This allows the eye to return to its more normal vision by returning the eye to a near physiologic or normal status. Every eye has different focusing powers because they differ in size and shape, like all human characteristics. Therefore each eye must have its power determined and calculated so that the correct replacement implant diopters power can be implanted. This measurement is done using ultrasound A-scan that measure the length of the eye much like a depth finder on a boat, that measures the depth of the water below the boat.  
           [0008]    By using regression formulas the power can be fairly accurately determined. The problem is that various errors can be introduced resulting in the placement of the incorrect power lens. Certain implants may not tolerated by the patient and must be replaced to clear their vision due to; the wrong power lens being implanted, the lens becoming displaced, or the patient is experiencing glare. There have been increasing numbers of exchanges over the recent years as patient expectations rise and the ability to get better visual results.  
           [0009]    This led to the development of a device that easily and safely removes implants. Making them easier to remove and carefully replaced with the proper lens.  
         SUMMARY OF THE INVENTION  
         [0010]    The present invention, the Siepser Splitter, is an intraocular device designed to cut or section an intra-ocular lens in the eye in order to remove it through the original small implantation incision. The device represents a departure from all present technology, which makes use of either a scissor or a snare like mechanism. The Siepser Splitter uses a unique basis for operation. Present scissor technology with ancient scissor action tend to induce what can be described as the watermelon seed effect, when the jaws of the scissor squeezes the implant it tends to shoot forward away from the jaws. Attempts to correct this problem have been to serrate the jaws to better grab the lens and hold it in place.  
           [0011]    Snare based technology exists, that uses a wire to grasp and then transect the implant much like a wire cheese cutter. This transects the lens but causes it to buckle and bunch up during the cutting process and this can cause damage to the eye as the lens springs back to its normal shape and can damage delicate structures of the eye.  
           [0012]    One advantage of the splitter is that it holds the implant and drives it into a sharp wedge that splits it for removal with a controlled action.  
           [0013]    The device has some of the characteristics of a hydraulic wood splitter. The main difference from present technology is that the Siepser splitter grabs the lens, holds it in position and gently sections it in half for removal from the eye. It can be made in a disposable or reusable model. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]    For the purpose of illustrating the invention, there is shown in the drawings a form, which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.  
         [0015]    [0015]FIGS. 1 through 8 illustrate an extraction device for a deformable intraocular lens according to one embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0016]    Referring now to the drawings, wherein like numerals indicate like elements, there is shown in FIG. 1 an example of an extraction device  10  for extracting a deformable intraocular lens.  
         [0017]    The extraction device  10  has a body  12  with a retracting band  14  that is movable within the body  12  and a cutting blade  16 . The retracting band  14  is moved so that it extends longitudinally out of the body  12  in order to engage an implanted deformable intraocular lens  30 . The retracting band  14  is extended out of the body  10  to engage and hold the lens  30  and draw it towards the cutting blade  16 . As the lens  30  is drawn into the cutting blade  16 , the lens is split allowing it to be safely retracted from the posterior chamber.  
         [0018]    In one aspect of the invention the body  12  has a cylindrical or tube like shape. The mechanism that moves the retracting band  14  is hand or finger actuated, and may include a plunger, screw, plier or lever, or a sliding slot action. The mechanism may use a cross or cam action to provide controlled unidirectional movement of the retracting band  14 .  
         [0019]    In another aspect of the invention, the retracting band  14  is a wire or a flattened loop that is wide enough to grasp the implant without cutting it. The retracting band  14  has a width between about 1 mm and 3 mm, and is may made from plastic, rubber, silicone, acrylic, Teflon, metal, titanium, surgical steel, or high carbon steel. The retracting band  14  is about 4-15 mm in length or longer as required by the material selected or type and size of intraocular lens to be extracted. The cutting blade  16  can be a flat or preferable a wedge shaped cutting blade.  
         [0020]    As shown in FIG. 2, the retracting band  14  captures and draws the lens  30  into the wedged shaped cutting blade  16  splitting the lens  30  akin to the action of a hydraulic wood splitter. In this context, instead of splitting the lens by driving a splitting tool into the material of the lens-which would be very ineffective since most lenses tend to slip away from such cutting methods-the present invention retains the lens  30  and slowly pushes it against an anvil like splitting wedge  16  that slowly and effectively cuts the lens  30 . In addition to cutting the lens  30 , the retracting band  14  stabilizes the lens  30  as it draws it into the cutting wedge  16 .  
         [0021]    The retracting band  14  can be made from a single piece of material or from welded components and is connected to an actuating plunger or rod. The rod can be moved in the handle to actuate the retracting band  14 .  
         [0022]    The mechanism for moving the retracting band  14  can be variable. A simple pull plunger can be grasped by the second hand to pull the retracting band forward. A single handed version can be made using the same technology with the retracting band  14  affixed to the base of the body  12  and the body  12  may itself be advanced over the retracting band  14  by sliding the body  12  back and forward over the retracting band  14 .  
         [0023]    As shown in FIG. 3, a bi-hinged scissor-like mechanism  18  can be used that pulls the retracting band  14  forward by compressing itself and extending out the end attached to the retracting band  14  that advances it in the tube-like body  14 . A screw-type action [not shown] device can also be used. For example, by twisting a knob at the base of the instrument the retracting band can be advanced on a screw that pulls it along. As shown in FIG. 4, a slot retractor action  20  can also be used to effect the movement of the retracting band  14 .  
         [0024]    The mechanical action retracting band  14  can also be developed by a cam-type action [not shown]. For example, the retracting band is attached to a pin in a cam that can be rotated drawing the retracting band toward. Also a crankshaft-offset action [not shown] can also be used to increase the throw and therefore the movement of the rod attached to the retracting band.  
         [0025]    As shown in FIG. 5, the cutting surface  16  on the wedge  22  can be sharpened plastic or steel. It can be a separate piece of surgical steel or specially prepared blade surface to cut and split the implant as it is drawn on to the blade area. The cutting blade  16  can be vertical, horizontal, or slanted in a way to increase the slicing effect of the cutting blade  16 . I may be curved or v shaped to assist in stabilizing and easing the cutting action of the cutting blade  16 .  
         [0026]    As shown in FIG. 6, a shoulder behind or as part of the cutting blade  16  helps to direct the cut pieces away from the delicate structures of the eye. The sluiceway directs the cut pieces and controls there movement. The retracting band  14  can be set so as not to fully transect the lens  30  allowing the two pieces to be more easily removed from the eye in one movement.  
         [0027]    As shown in FIG.&#39;s  7  through  9 , an another aspect of the invention includes a split or two piece retraction band  14 . In this aspect the bands are split at the tip  26  of the retraction band  14 . As the bands are extend out from the body  12  they separate to provide longitudinal access to the tens  30  without the need to angle the device  10  and avoid further disruption to the incision site.  
         [0028]    These and other advantages of the present invention will be apparent to those skilled in the art from the foregoing specification. Accordingly, it will be recognized by those skilled in the art that changes or modifications may be made to the above-described embodiments without departing from the broad inventive concepts of the invention. It should therefore be understood that this invention is not limited to the particular embodiments described herein, but is intended to include all changes and modifications that are within the scope and spirit of the invention as set forth in the claims.