Abstract:
A speculum for the insertion and expanding of a body cavity. The speculum comprises a plurality of blades pivotally connected around a ring-shaped frame, the first ends thereof extending longitudinally and meeting at a point distant from the frame to form a generally bulbous end and the second ends which are manipulated to rotate the blades about the frame. A rotating action of the second ends causes the first ends to angularly move away from each other to expand the bulbous end, and hence the body cavity. A series of block pivotally attached to the frame interact with the second ends to form a ratcheting locking means to lock the blades at certain positions between a closed position and an open position.

Description:
[0001]     This invention relates to specula that are inserted into body cavities and manipulated to spread or open the cavity for observation.  
       BACKGROUND OF THE INVENTION  
       [0002]     Specula are used to examine interior portions of a body through cavities. The specula is placed into the cavity and expanded to open the cavity while at the same time permitting a physician to view the inside of the cavity. Various types and designs of specula are well known. A typical type is disclosed in U.S. Pat. No. 5,072,720, wherein a pair of duck-bill blades are slidably attached to each other. The blades are inserted into a body cavity and manipulated to move the blades apart from each other to form a cavity therebetween. The physician then views the cavity walls through a space formed between the blades.  
         [0003]     Another design for a speculum is disclosed in U.S. Pat. No. 5,916,151, wherein four blades spaced apart are connected by cables to a pair of rings, at a center portion thereof and an end portion. The distal ends of the blades are generally in a side by side relationship and movable laterally with respect to each other between a contracted position wherein the distal ends are closely adjacent to each other to an expanded condition wherein the blades are separated from each other. The blades are placed into the body cavity in the contracted position and then manipulated, via the cables, to the extended condition to open up the cavity.  
         [0004]     While these specula perform satisfactorily in most conditions, their insertion and manipulation can cause discomfort to the patient. The disadvantage of the older duck-bill type specula is that the peripheral edge of the blades can cause discomfort during insertions and removals. Such blades can also pinch interior walls when the blades are moved back together during removal of the speculum following an observation by the physician.  
         [0005]     A disadvantage with the four blade design is that the blades hang loose in the cables, where it is possible for one or more of the blades to extend in undesired directions during insertion or during manipulation causing discomfort. Such a design requires the physician to manually hold the blades together during insertion and monitor closely the positions of the blades.  
       SUMMARY OF THE INVENTION  
       [0006]     It is therefore an object of the present invention to overcome these and other problems in the prior art by providing a speculum that is compact, easy to insert into the cavity and manipulate, which together will provide less discomfort to the patient than prior specula.  
         [0007]     The speculum according to the invention comprises a plurality of blades positioned generally parallel to each other and hinge coupled to a frame at points in between their end sections. In a closed position, first end sections of the blades meet adjacent each other at a distal end from the frame. Spring mechanisms bias the first end sections of the blades towards each other. Between the first end sections and the frame, the blades define a generally cylindrical envelope with a bulbous end. The cylindrical envelope created by the first end section can then be inserted into the body cavity. The bulbous end prevents easy removal of the speculum from the cavity. Upon rotation of the blades about the hinge against the action of the springs, the first ends of the blades move away from each other to increase the cavity there between. Such movement of the blades into an open position changes the cylindrical envelope into more of a conical envelope, and hence increases the body cavity size to allow for viewing of the body cavity walls from outside the cavity.  
         [0008]     In a preferred embodiment, the speculum has a locking mechanism comprising ratcheting blocks which act in conjunction with second ends of the blades located on the ends opposite the first ends. The blocks are connected to the frame by means of pins. Springs bias the blocks into contact with the seconds ends. A series of stops on sides of the blocks contacts the second ends and prevents a closing action of the blades. Each stop holds the respective blade at a certain amount of rotation about the hinge, thus allowing the speculum to be maintained at varyied open positions. A rotation of the blocks against their respective biasing springs releases the blades to close the blades.  
         [0009]     The frame has generally an annular shape with a hollow center. In a preferred embodiment, the blades are hinged at an outer surface of the disc, the first ends extending through the center of the frame. When the blades are in open positions and first ends of the blades are separated from each other, the physician is able to look through the center of the frame and observe the cavity into which the first ends of the speculum are placed.  
         [0010]     Such a novel and improved speculum can be used in a variety of services, particularly vaginally during gynecologic procedures, including endoscopic Pap tests, endoscopic colposcopy, tissue biopsy, cryotherapy, loop electroexcision and other procedures. The speculum according to this invention will cause minimal distention of the female pelvic floor while providing satisfactory distention and thus exposure for examination of the upper vagina and cervix. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The invention will now be described in detail in conjunction with several drawings, in which:  
         [0012]      FIG. 1  is a side view of the speculum according to this invention;  
         [0013]      FIG. 2  is a bottom side view of the speculum shown in  FIG. 1 ;  
         [0014]      FIG. 3  is an enlargement of section A of  FIG. 1 ;  
         [0015]      FIG. 4  is an enlargement of section B of  FIG. 2 ;  
         [0016]      FIG. 5  is a perspective view of the hinge and locking mechanism of the speculum shown in  FIG. 1 ;  
         [0017]      FIG. 6  is another side view of the speculum shown in  FIG. 1  in an open position;  
         [0018]      FIG. 7  is a bottom view of the speculum shown in  FIG. 6 ;  
         [0019]      FIG. 8  is a perspective view of a speculum according to this invention; and  
         [0020]      FIGS. 9A-9D  are cross sections of alternate blade designs. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]     The preferred embodiment of the invention is shown in  FIGS. 1-5 . As shown in the figures, the speculum  1  has a generally elongated shape, consisting of an insertion end  10 , extending towards a front end of the speculum and a control end  20 , extending to a rear of the speculum. The speculum comprises four blades (three visible in the figure)  110 ,  120 ,  130  and  140  extending from a frame member  100 . The blades have first sections  115 ,  125 ,  135  and  145  extending forward in the front end  10  of the frame and second sections  116 ,  126 ,  136  and  146  extending behind the frame in the control end  20 . Each of the blades is attached to the frame via hinges  150 ,  151 ,  152  and  153  (three shown), which provides for rotation of the blades with respect to the frame and each other.  
         [0022]     As shown in the figures, particularly,  FIG. 2 , the frame  100  has a generally octagonal shape with an opening forming a hollow center, however, other shapes for the ring may be used, such as circular, triangular, rectangular, etc., depending on the particular design of the speculum or the number of blades required for the speculum, and as long as the center of shape is open. The octagonal shape is shown as an example. The hinges  150 ,  151 ,  152  and  153  that attach the blades  110 ,  120 ,  130  and  140  to the frame  100  are located on the outer surface thereof. The first sections  115 ,  125 ,  135  and  145  of the blades then extend through the center of the frame  100  and extend in the forward direction to form the insertion end  10 .  
         [0023]     Each blade is generally divided into four sections, for example, with respect to blade  110 , the second section  116  is one section and the first section  115  is divided into three sections, namely a neck portion  112 , an intermediate portion  113  and an end portion  114 . Each blade has similar features. The end portion  114  is at the front of the speculum and has a curved shape and a tip  111  that abuts a central axis RA extending from the center of the frame  100 . Each of the other blades  120 ,  130  and  140  have such a curved shape end portion  124 ,  134  and  144  and each blades&#39; tips  121 ,  131 , and  141  abuts each other at the central axis, as shown in  FIG. 2 . Such features provide a generally rounded end for the speculum, which is shown in  FIG. 1 , to allow for an easy insertion of the first sections  115 ,  125 ,  135  and  145  into a body cavity and reducing discomfort to the patient.  
         [0024]     The neck portion  112  of blade  110  extends from the hinge  150  to the intermediate portion  113 . As the neck portion passes through the center of the frame  100 , it begins to converge on the central axis RA. Each of the other blades has a similar neck portion that converges on the central axis RA. The grouping of the neck portions forms a generally conical shape.  
         [0025]     The intermediate section  113  extends between the neck portion  112  and the end portion  111  of blade  110 . The intermediate section  113  at the neck portion begins near the central axis RA and extends away until it connects to the end portion  111 . The intermediate sections  123 ,  133  and  144  of the other blades have a similar design. The combination of these intermediate sections provides a generally bulbous end to the insertion end  10 . The bulbous end aids in maintaining the insertion inside the cavity.  
         [0026]     The hinges  150 ,  151 ,  152  and  153  between the blades  110 ,  120 ,  130  and  140  and the frame  100  are shown in detail in  FIGS. 2 and 4 .  FIG. 4  is a blown up view of hinge  151  between blade  120  and frame  100 . The hinge  151  consists of a hinge pin  161  which is attached to frame  100 . The blade  120  fits over the pin  160  and rotates about the pin. A hinge spring  171  is connected between the frame  100  and blade  120  to bias blade  120  to rotate in a certain direction (discusses below). Each blade has similar hinge pins  160 ,  162  and  163  and hinge springs  170 ,  172  and  173  designs, as shown in  FIG. 2 . While the hinge pins here are shown and disclosed attached to the frame, they may alternatively be attached to the blade. Either or other designs may be used as long as the blades hinge about the frame.  
         [0027]     The second sections  116 ,  126 ,  136  and  146  extend in a direction generally behind the frame in the control end  20  and attach to the first sections  115 ,  126 ,  136  and  146  at the hinges  150 ,  151 ,  152  and  153 . A physician using the speculum manipulates the second sections to operate the speculum. As shown in  FIG. 6 , pressure along line B 1  towards the central axis RA against the second section  116  of blade  110  causes the blade to rotate about hinge  150 . During the rotation, the end portion  114  begins to move away from the central axis RA.  
         [0028]     A similar event occurs when each of the second sections  126 ,  136  and  146  of blades  120 ,  130  and  140  are pushed or pulled towards the central axis RA. Such actions cause each of the end portions  124 ,  134  and  144  to move away from the central axis RA. This causes the insertion end  10  of the speculum  1  to move into an open position with the blades apart, as shown in  FIG. 8  allowing for the body cavity to be opened up. In the full open position (shown), the neck portions of each of the blades are no longer in a conical shape, but rather are parallel to each other and parallel to the central axis RA. These features of the open position along with the open center of the frame allow for a physician to view along center axis RA, as shown in  FIGS. 6 and 8  along line VA, the inside of the body cavity opened up by the speculum. The view is shown in  FIG. 7 .  
         [0029]     Upon release of the pressure against the second sections  116 ,  126 ,  136  and  146 , the blades rotate back in the direction B 2  towards the closed position, as shown in  FIGS. 1 and 2  through the action of the springs  161 ,  162 ,  163  and  164  at the respective hinges  150 ,  151 ,  152  and  153 . Thus, the end portions  111 ,  121 ,  131  and  141  are biased and move towards center axis RA so that the blades, and hence the insertion end, move to the closed position.  
         [0030]     In another embodiment of the invention, the speculum is provided with a locking mechanism to hold the speculum at various positions between the closed position and the open position. Such mechanisms are shown in  FIGS. 1, 2 ,  3  and  5 . The mechanisms comprise a series of blocks  200 ,  201 ,  202  and  203  which interact with the second sections  116 ,  126 ,  136  and  146  of the blades. The blocks are pivotally connected to the frame  100  via block pins  210 ,  211 ,  212  and  213  to allow rotation of the blocks in a direction generally perpendicular to the central axis. Block springs  220 ,  221 ,  222  and  223  mounted between the blocks and the frame around the pins bias the blocks to rotate in a certain direction.  
         [0031]     In the detail shown in  FIGS. 3 and 5 , blade  120  is shown in conjunction with locking mechanism block  201 . As shown, the block rotates about pin  211 , generally perpendicular to the rotation of blade  120 . The rotation is biased from block spring  221  to rotate in the direction of arrow L 1  and press surface  251  against the second section  126  of blade  120 . A series of stops  310 ,  311 ,  312  and  313  along the surface  251  provide locking contacts. When the second section is rotated inward along in the direction B 1 , the second section moves past the stops. The block spring  211  pushes the block against the second section causing it to click over the stops. When the pressure moving the second section in the direction B 1  is ceased, hinge spring  161  biases the second section  120  in the direction B 2 , however, the last stop the second section passed prevents movement of the second section past that last stop. For example, in  FIG. 5 , the second section had last passed stop  311 . Upon the cessation of the pressure against the second section in the direction B 1 , the hinge spring would bias the second section against stop  311 , which prevents the second section from moving further in the direction B 2 , towards the closed position of the speculum. This action thus, locks the second section in the stop  311  position, holding the blade in the open position.  
         [0032]     To unlock the locking mechanism to release the second section and allow it to return in the direction B 2  towards the speculum closed position, the block  201  is rotated in the direction C 2 , which pulls the stops  310 ,  311 ,  312  and  313  away from the second section, allowing it uninterrupted movement in the direction B 2  until is arrives at the closed position.  
         [0033]     Similar locking mechanisms are provided using blocks  200 ,  202  and  203  in conjunction with their respective block pins and block springs and such locking mechanisms lock the release their respective second sections in a similar manner.  
         [0034]     In operation of the speculum, by either a physician or otherwise, the speculum is held at the control end. The action of the hinge springs  160 ,  161 ,  162  and  163  bias the insertion end  10  of the speculum  1  in the closed position, as shown in  FIG. 1 . The closed position allows for easy insertion of the insertion end  10  into the body cavity without difficulty and causing little discomfort. The insertion end  10  is inserted into the cavity until the frame nearly abuts the rim of the body cavity or until the rim of the body cavity nears the portions of the blades between the neck portions and the intermediate portions.  
         [0035]     The physician then manipulates each of the second sections  116 ,  126 ,  136  and  146  of the blades by moving them in the direction B  1  towards the central axis RA of the frame. Such action causes the first sections  115 ,  125 ,  135  and  145  of the blades to begin to separate and open the insertion end  10  inside the body cavity. As the physician continually rotates the second sections, they continually click past stops on the locking blocks  200 ,  201 ,  202  and  203 , which are biased against them. When either the physician has fully opened the speculum or the first sections are opened as far as the body cavity will allow, the physician simply releases or ceases further rotation of the second sections in the direction B 1 . The speculum has then been put into the open position which opens the body cavity. The hinge springs  160 ,  161 ,  162  and  163  will then cause the second sections to rotate in the direction B 2  until the second sections move into contact with the last stops on the locking blocks each passed. The stops will hold the respective second sections in place.  
         [0036]     At this point, the physician can release the speculum and begin to take the proper tests within the cavity or view the cavity through the speculum. Such can be done by simply passing instruments through the frame center or by looking through the frame into the cavity which is opened up by the first sections.  
         [0037]     When the physician has completed necessary actions and desires to remove the speculum, the blocks are simply rotated in the direction C 2  to pull the stops away from the second sections, which releases the second sections and allows them to freely move in the direction B 2  until the insertion end  10  of the speculum reaches the closed position under the action of the hinge springs. Once the speculum returns to the closed position, it can be removed from the body cavity.  
         [0038]     From the forgoing description, it is evident that there are a number of changes, modifications or alterations that can come within the province of a person having ordinary skill in the art. For example, this specification discloses a blade design that is round in shape, as shown in  FIGS. 8 and 9 A, however, various other designs are possible. For example, the blades may be of a u-shape as shown in  FIG. 9B , a v-shape as shown in  FIG. 9C  or a rounded square shape as shown in  FIG. 9D . Other possibilities are also possible depending on the particular design of the speculum and the material used for the blades. It is evident that any such changes, modification or alterations are specifically included in this description and this invention should only be limited by the claims following hereinafter.