Abstract:
A scleral depressor designed to better control the globe of the eye is disclosed. In a preferred embodiment, the scleral depressor has a handle and a blade attached to the handle where the blade is a portion of an oblate spheroid. In one embodiment, the blade has an illuminating device. The handle is attached to the blade at an angle or straight in relation to the plane of the handle. In another embodiment, the blade is attached to a thimble. In another embodiment of the invention, the blade has an access hole for simultaneous use of other instruments during examination or surgery. The resulting apparatus has greatly improved control of the eye, effective visualization of the periphery, ease of use for the examiner, and increased comfort for the patient.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to U.S. Provisional Application No. 60/847,924, which was filed on Sep. 29, 2006, and U.S. Provisional Application No. 60/868,877 which was filed on Dec. 6, 2006, and both are incorporated herein by reference in their entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an ophthalmic surgical and examination tool used for depressing the sclera during an eye examination. More particularly, the present invention relates to a scleral depressor that provides improved manipulation and control over eye position. 
     BACKGROUND OF THE INVENTION 
     A scleral depressor is used to facilitate examination of a fundus of an eye, particularly its periphery. During an ocular fundus examination, and particularly during the study of areas of the retina such as the periphery, it is necessary to control the position of the eye. Several sclera depressors have been designed for this purpose. For example, the Storz Instrument Company catalog illustrates several such depressors. These scleral depressors include bulbous or ball end depressors, T-bar depressors, ring depressors, and flat spatula depressors. 
     The instruments disclosed in the prior art comprise a handle, with optional pocket clip, which is attached to the blade either straight or at an offset angle to facilitate manipulation of the blade from a position that leaves the field substantially clear for the simultaneous use of other instruments, such as an opthalmoscope. 
     U.S. Pat. No. 4,453,546 discloses a scleral depressor for controlling eye position that has a substantially oblong-shaped blade. The blade has a textured surface with a hole substantially in the middle of the blade. In operation, the blade is manipulated by the operator to depress against the sclera of a patient&#39;s eye for either rotating or immobilizing the globe of the eye during examination. 
     U.S. Pat. No. 6,440,065 discloses an eyelid speculum and scleral depressor for controlling eye position by pressing against the sclera of the eye with a depressor. The scleral depressor has an elongated handle portion, two stem portions and two blades. The blades are flat and substantially paddle-shaped. 
     In addition to these more conventional prior art devices, some unconventional means, such as paper clips, safety pins, cotton tipped applicators and strabismus hooks are used for the above stated purposes. These type of scleral depressors are not ideally suited for examination for the following general reasons: (a) the tips of these depressors are bulky and with a pediatric lid speculum in place it is often difficult to find adequate room to insert an instrument into the conjunctival sac; (b) undue pressure on the globe and compromise of the ocular circulation is therefore possible; and (c) these scleral depressors have smooth surfaces, slide on the globe, and will not rotate it to different examination positions. 
     Additionally, both the conventional and unconventional scleral depressors are often difficult to use in conjunction with other instruments because they are not designed for operation from a position which will leave the field substantially clear for the simultaneous use of these instruments in the examination of the eye. 
     BRIEF SUMMARY OF THE INVENTION 
     There is a need to make a scleral depressor that can not only maintain good control of the globe of the eye and provide adequate visualization of the periphery, but is also easy to use for the examiner and comfortable for the patient. 
     A scleral depressor designed to better control the globe of the eye is disclosed. In a preferred embodiment, the scleral depressor has a handle and a blade attached to the handle where the blade is a portion of an oblate spheroid. In one embodiment, the blade has an illuminating device. The handle is attached to the blade at an angle or straight in relation to the plane of the handle. In another embodiment, the blade is attached to a thimble. In another embodiment of the invention, the blade has an access hole for simultaneous use of other instruments during examination or surgery. The resulting apparatus has greatly improved control of the eye, effective visualization of the periphery, ease of use for the examiner, and increased comfort for the patient. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For the purposes of illustrating the present invention, there is shown in the drawings a form which is presently preferred, it being understood however, that the invention is not limited to the precise form shown by the drawing in which: 
         FIG. 1  is a front elevational view of a portion of the depressor; 
         FIG. 2  is an orthogonal view of a portion of the rear of the depressor; 
         FIG. 3  is an orthogonal view of a portion of the front of the depressor; 
         FIG. 4  is a front orthogonal view of a scleral; 
         FIG. 5  is a rear elevational view of a portion of the scleral depressor; 
         FIG. 6  is a front elevational view of a portion of the scleral depressor; 
         FIG. 7  is an orthogonal view of a double ended scleral depressor; 
         FIG. 8  is an orthogonal view of a double ended scleral depressor; 
         FIG. 9  is an orthogonal view of a thimble scleral depressor; 
         FIG. 10  is an orthogonal view of a thimble scleral depressor. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     During fundus examination, the slender oblong curved blade of the disclosed scleral depressor can be easily positioned around the globe, whether over the eyelid, along the crease when examining the superior and inferior peripheral retina, or directly on the globe in the medial or lateral conjunctival sac when evaluating the medial or temporal peripheral fundus. The oblong curved blade is wider than the T-bar tip or bulbous end of conventional scleral depressors. Thus, it indents a larger surface area in the peripheral retina allowing visualization of a wider field with less manipulation of the globe. In a preferred embodiment, the oblong curved blade is substantially between ⅛ of an inch and 1 inch wide and between ⅛ of an inch and 1 inch long. In a preferred embodiment, the oblong curved blade is ¼ inch wide and ¾ inch long. 
       FIG. 1  illustrates a front elevational view of the scleral depressor  100 , comprising a blade  120  and a handle portion  110 . In this embodiment of the invention the blade  120  is in a portion of an oblate spheroid, which is attached to the handle portion  110 . In one embodiment, the partially spheroid oblate shaped blade  120  has a smooth curved surface. The partially spheroid oblate shaped blade  120  is preferably angled relative to the handle portion  110  to allow manipulation of the partially spheroid oblate shaped blade  120  from an offset position. 
     During fundus examination, the partially spheroid oblate shaped blade  120  can be positioned easily around the globe or over the eyelids along the lid creases when examining the superior and inferior peripheral retina. The partially spheroid oblate shaped blade  120  can also be placed directly on the medial or lateral conjunctival sac to maneuver and hold the globe in place when evaluating the medial or temporal peripheral fundus. Due to the configuration of the partially spheroid oblate shaped blade  120 , the globe can be held effectively into the desired position by the examiner without causing discomfort to the patient such as that caused by other scleral depressors. 
     The partially spheroid oblate shaped blade  120  has more surface area than a T-bar tip and allows visualization of a wider field without excessive manipulation of the globe. The angled attachment of the partially spheroid oblate shaped blade  120  to the handle portion  110  also provides a substantially clear field during examination. 
     Referring now to  FIG. 2  and  FIG. 3 , two views of the embodiment of  FIG. 1  are shown.  FIG. 2  illustrates an orthogonal view of a portion of the rear of the scleral depressor  100 , depicting a rear blade portion  230  and a handle portion  110 .  FIG. 3  illustrates an orthogonal view of a front portion of the scleral depressor  100 , comprising an front blade portion  320  and a handle portion  110 . In one embodiment of the invention, the partially spheroid oblate shaped blade is connected to the handle via a curved connector. 
     In another embodiment, illustrated in  FIG. 4 , scleral depressor  400  comprises a blade portion  430 , a stem  410 , and a handle portion  420 . As depicted in  FIG. 4 , stem  410  joins the blade portion  430  and the handle portion  420 . In this embodiment, the scleral depressor  400  is a single-tipped instrument attached to a straight handle  420 . In another embodiment, the stem  410  creates an angle between the blade portion  430  and the straight handle  420 . In a preferred embodiment, the stem  410  is narrow providing a larger field of view. 
     Handle portion  420  is designed for use during examination, the operating room, and for scleral depression under a microscope. The stem  410  easily slides under a speculum avoiding the use of cotton swabs, muscle hooks, or other devices. Such a configuration makes depression faster, easier and safer. In one embodiment, the handle portion  420  is serrated for easier handling. 
     Referring now to  FIG. 5  and  FIG. 6 , two different views of the embodiment of  FIG. 4  are shown.  FIG. 5  is a rear elevational view of a portion of the scleral depressor  400 , comprising a partially spheroid oblate shaped blade  530  and a stem  410 . Whereas,  FIG. 6  is a front elevational view of a portion of the scleral depressor  400 , comprising a partially spheroid oblate shaped blade  630  and a stem  410 . 
     In an embodiment as shown in  FIG. 7 , scleral depressor  700  comprises a blade portion  770 , a first stem  710 , a handle portion  740 , a pocket clip  730 , a second stem  750 , and a bulbous end  760 . As depicted in  FIG. 7 , the scleral depressor  700  is double-ended. In this embodiment of the invention, the blade portion  770  is a blade that is a portion of an oblate spheroid attached to the first stem  710 . The first stem  710  is connected to a first end of handle portion  740 . 
     The other end of handle portion  740  is to the second stem  750  which connects to a bulbous end  760 . It should be noted that while a bulbous end is shown, the second end of the scleral depressor can be a T-bar depressor, a spatula, or another blade that is a portion of an oblate spheroid. In one embodiment, the scleral depressor has blades that are a portion of an oblate spheroid at both ends, each being a different size. A pocket clip  730 , attached to the handle portion  740  of the scleral depressor. This pocket clip  730  can not only be attached to examiner&#39;s clothing when scleral depressor  700  is not being used but it can also aid the examiner in stabilizing and controlling the manipulation of scleral depressor  700 , for example, by inhibiting unwanted rotation of the handle portion  740 . 
       FIG. 8  is an orthogonal view of a scleral depressor  700  where only one end of the scleral depressor is shown.  FIG. 8  comprises a larger blade portion  870 , a first stem  710 , and a handle  820 . As shown in the drawings the first stem  710  is rigidly attached to one end of handle  820  by any suitable means. In one embodiment, the entire scleral depressor is cast as a single piece. In another embodiments the handle and blade ends are cast separately. The handle and blade ends are then attached by suitable methods including welding, soldering, pressure fitting, screws, epoxy, or the like. In this manner, if a component of the scleral depressor is damaged, the damaged portion can be replaced. 
       FIG. 9  depicts an orthogonal view of a thimble scleral depressor  900 . The scleral depressor  900  includes a partially spheroid oblate shaped blade  940  that is a portion of an oblate spheroid. The partially spheroid oblate shaped blade  940  is attached to an extension portion  910 . The extension portion  910  is attached to thimble  920  at the end opposite the partially spheroid oblate shaped blade  940 . The partially spheroid oblate shaped blade  940  in this embodiment is angled relative to the extension portion  910  to allow manipulation of the partially spheroid oblate shaped blade  940  from an offset position. 
     The partially spheroid oblate shaped blade  940  has a smooth curved surface. In another embodiment, the partially spheroid oblate shaped blade  940  is textured or coated with diamond dust to the like to increase the coefficient of friction of the blade. The partially spheroid oblate shaped blade  940  conforms to the curvature of the eye. The partially spheroid oblate shaped blade  940  is made to generally match the shape of the human eye. Due to the shape of the partially spheroid oblate shaped blade  940 , it does not slide on the sclera of the eye during examination and provides easier scleral depression. 
     As illustrated in  FIG. 9 , the scleral depressor has a hole  945  in the blade. This hole  945  can facilitate in gripping and gaining control of the eye during an examination or during surgery. Additionally, surgical tools can also be inserted through access hole  945  during examination or surgery of an eye. In one embodiment, an LED or other light source is integrated into the blade  940  of the scleral depressor  900 . This provides improved illumination in the operating room. In one embodiment, a light ring  950  arranged substantially around the access hole  945  illuminates the relevant field. Alternatively, the light ring is provided about the periphery of the blade  940 . In another embodiment, a light source  930  provides illumination. In yet another embodiment, the curved tip of the scleral depressor is illuminated using fiber optics or the like. 
     Any embodiment of this invention can further be used for veterinary applications. In any embodiment of this invention the scleral depressor can be metal, plastic, carbon fiber, or the like. Further, various features of each embodiment can be combined. Additionally, in one embodiment, the tool is partially flexible to conform exactly to the human eye. 
     Because of the ease of use of the scleral depressor in any of the embodiments described above, an examiner with beginner skill level can also use this tool effectively in performing funduscopy. Further, the disclosed depressor fits easily into lid creases. The shape provides a broader field of depression and is more efficient than T-bars. 
       FIG. 10  is another orthogonal view of a thimble scleral depressor  1000 .  FIG. 10  comprises a blade  1040  that is a portion of an oblate spheroid attached to an extension portion  1010 , and a thimble portion  1020 . Extension portion  1010  can be straight, curved, bent, or the like. 
     Having thus described at least illustrative embodiments of the invention, various modifications and improvements will readily occur to those skilled in the art and are intended to be within the scope of the invention. Accordingly, the foregoing description is by way of example only and is not intended as limiting. The invention is limited only as defined in the following claims and the equivalents thereto.