Abstract:
The invention relates to a direct reading endoscopic measuring instrument and, more specifically, to a manually operated measuring instrument that is placed in close proximity to an internal anatomical feature and a related method for operation of the measuring instrument. The direct reading endoscopic measuring instrument includes a distal reticule that is passed through an endoscope in a folded position. When extended past the distal end of the endoscope proximate to an anatomical structure to be measured, a remote actuator unfolds the reticule along an axis perpendicular to the endoscope. Graduations on the reticule can be observed to directly measure the size of the anatomical structure.

Description:
[0001]     The present invention relates to a direct reading endoscopic measuring instrument and, more specifically, to a manually operated measuring instrument that is placed in close proximity to an internal anatomical feature and a related method for operation of the measuring instrument.  
         [0002]     BACKGROUND  
         [0003]     With advances in optics and miniaturized assembly techniques, endoscopes now play a vital role in modern medicine. Endoscopes are flexible surgical tools used to introduce mechanical instruments, fluids, viewing instruments, and the like into a body. An endoscope, which generally has a tubular shape, is fed into an opening or incision in a body until the distal end of the endoscope is proximate a site to be observed or operated on. The interior of the endoscope includes one or more bores or lumens. These lumens act as passages for various instruments or tools that facilitate diagnostic or therapeutic procedures. For instance, a fiber optic cable with an optical lens (camera) can be integral to the endoscope or extended the length of the endoscope. The camera is operable to view the tissue proximate to the digital end of the endoscope. Other lumens can be used to provide light, fluids, mechanical surgical tools, or the like. Endoscopes are extremely useful to observe or biopsy internal organs such as the colon, bladder, stomach, lungs, liver, or the like. Overall, endoscopes have revolutionalized many procedures by giving the operating doctor much greater information from, and access to, internal structures without an invasive procedure. Doctors can now observe and diagnose organs and joints with minimal impact.  
         [0004]     One area where endoscopes are used routinely is in the observation and measurement of tumors, internal growths, or other anatomical structures (ulcers, tears, scars, etc.). The size of such structures can be measured in a variety of ways. For instance, it is known to place graduations onto the camera lens of a fiber optic camera placed within an endoscope. Although the graduation measurements on the lens may be known, it is only possible to estimate the size of the internal structure because the distance from the lens to the structure is unknown. This type of measurement technique does not provide the depth of the structure. Another common solution is to electronically calculate the size of a structure. To accomplish this, a tool with uneven graduations will be placed near a structure. The observation equipment calculates a size scale to correct for the uneven graduations. This approach is generally expensive, overly complex, and not entirely accurate. Typically, this calculated method, as opposed to a direct reading method, will only measure the structure in one direction.  
         [0005]     Measurement tools are known to have unevenly spaced graduations that are formed at a tip end portion of a flexible shaft. The shaft is detachably inserted through an instrument tool channel in an endoscope. The shaft is placed next to the structure, and can be observed via a camera. Again, the size of an internal structure can only be measured in one direction. The orientation of the shaft prohibits measurements in two directions. So while it is thought to be an improvement to have a direct reading tool, it is also thought to be nearly impossible to directly measure the dimensions of an object in two different directions with such a tool. Moreover, the known tools may require more than one measuring instrument, endoscope, or are otherwise overly complex. Direct reading tools may not take measurements along an axis perpendicular to the endoscope.  
         [0006]     As such, there is a clear need within the medical industry for an inexpensive, easy to operate, simple, durable, and selectively removable direct reading endoscopic measurement instrument (‘DREMI’). Ideally, the DREMI provides accurate measurements of internal structures in at least one direction, including along an axis perpendicular to the endoscope. The apparatus and method of the present invention would effectively address shortcomings as known in the prior art.  
       SUMMARY OF THE INVENTION  
       [0007]     In accordance with the present invention, a DREMI, and method for operating the DREMI, are provided that include a manually operated measuring instrument that is placed in close proximity to an internal anatomical feature. The DREMI is inserted into a body, such as a human body, through an endoscope. When the DREMI is properly positioned, a reticule is unfolded proximate to an anatomical structure. Using evenly spaced graduations on the reticule, an operator can directly measure the structure via an endoscopic camera, as known in the art, that is included in the endoscope.  
         [0008]     The distal reticule provided by the DREMI is extended past the distal (inserted) end of the endoscope in a folded condition. A manual actuator, as known in the art, is operable to unfold the distal reticule proximate to the anatomical feature once the reticule has exited the endoscope. In the unfolded state, the distal reticule is substantially perpendicular to the axis of the endoscope. The graduations on the DREMI allow an attendant, physician or other operator to directly measure the size of the anatomical feature in question in at least one direction, including along an axis perpendicular to the endoscope.  
         [0009]     The DREMI includes the manual actuator, a coil pipe with an actuator wire, and the distal reticule wherein the actuator wire connects the actuator to the unfoldable distal reticule. The coil pipe and folded distal reticule are inserted into a channel provided by an endoscope, either before or after the endoscope is positioned with the body. The actuator is external to both the body and endoscope for actuation by an operator. The size and length of the DREMI will be determined, in part, by the size and length of the endoscope being used for the particular medical procedure that is to be performed. The reticule is naturally biased into the folded position.  
         [0010]     In a preferred embodiment, the actuator is a commonly used slide trigger that is secured to both the proximal end of the coil pipe and to an actuator wire for selectively unfolding the distal reticule. Sliding the trigger towards the coil pipe along the length of the actuator operates to retract the actuator wire at the distal reticule. Retracting the actuator wire causes the reticule to unfold when the reticule has been passed out of the distal end of the endoscope. Other types of actuators are available, and the structure of the actuator and direction of activation are not important to the present invention.  
         [0011]     In one preferred embodiment, the reticule includes evenly spaced graduations along at least a portion of the length of the reticule. The graduations are visible in both the unfolded and folded states via an endoscopic camera. In this manner, the DREMI can be used to measure an anatomical structure in at least one direction, including along an axis perpendicular to the endoscope. The image from the endoscopic camera does not need to be scaled.  
         [0012]     A DREMI and the related method of operation in accordance with the present invention efficiently address at least one of the shortcomings associated with prior art endoscopic measuring devices. The foregoing and additional features and advantages of the present invention will become apparent to those of skill in the art from the following detailed description of a preferred embodiment taken in conjunction with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is a perspective view of a DREMI in accordance with one embodiment of the present invention;  
         [0014]      FIG. 2  is a close-up view of a DREMI in accordance with the present invention wherein the DREMI is extending out of the distal end of an endoscope;  
         [0015]      FIG. 3  is a close-up view of the distal end of a DREMI in accordance with the present invention;  
         [0016]      FIG. 4  is another close-up view of the distal end of a DREMI in accordance with the present invention;  
         [0017]      FIG. 5  is a side view of the reticule provided by the DREMI wherein the reticule is spread apart along the length of the reticule; and  
         [0018]      FIG. 6  is a bottom view thereof. 
     
    
     DETAILED DESCRIPTION  
       [0019]     A DREMI in accordance with the present invention provides the medical industry with an inexpensive, easy to operate, simple, durable, and selectively removable direct reading endoscopic measurement instrument. The DREMI provides accurate measurements of internal structures in at lease one direction, including along an axis perpendicular to the endoscope.  
         [0020]     Turning to  FIG. 1 , the DREMI  10  is illustrated as including an actuator  12 , a coil pipe  14  with an actuator wire  16 , and a distal reticule  18 . Actuator  12  is connected to the distal reticule by the coil pipe and actuator wire. The coil pipe and actuator wire are illustrated here in broken lines to convey the length of the DREMI. DREMI  10  will be fed through an endoscope in order to reach an internal anatomical structure. The length of the coil pipe and actuator wire must be sufficient to extend the distal reticule past the distal end of the endoscope. Coil pipe  14  might be encased by a larger outer coil pipe  20  near the actuator for increased durability. Outer coil pipe  20  would terminate at a relatively short distance in comparison to the length of coil pipe  14 .  
         [0021]     In a preferred embodiment, actuator  12  is a commonly used actuator. For instance, the illustrated actuator is available from Olympus™, and it can be used with a number of endoscopic tools. Actuator wire  16  is thread through coil pipe  14  and connects a slide  22  on actuator  12  with a distal tool, in this case distal reticule  18 . The actuator body is an injection molded plastic secured, by known means, to coil pipe  14  and optional outer coil pipe  20 . The actuator wire passes from slide  22  to the inside of coil pipes  14 ,  20  via an aperture sized and dimensioned to accept wire  16 . The connection of wire  16  to slide  22  is not important for the present invention and is known in the art.  
         [0022]     The end of actuator  12  opposite coil pipe  14  provides a thumb grip  24 . In use, a user places their thumb in grip  24  with slide  22  between their index and middle fingers. Slide  22  can then be forcibly positioned along a shaft  26 . Pushing slide  22  away from grip  24  (i.e., pushing wire  16  toward reticule  18 ) places a force at the distal end of the wire on distal reticule  18 . Releasing slide  22  allows the slide to return to a natural resting position. Further discussion of the actuator  12  is not warranted here as it is a known device and operation of the actuator will be obvious to one of skill in the art. Various types of actuators are commercially available and would be suitable for use with the DREMI.  
         [0023]     Turning to  FIG. 2 , there is illustrated the distal end of an endoscope  30  with bores or lumens. The lumens act as channels for various tools or fluids. The procedure and type of endoscope both used largely determine the functionality of each lumen. For use with DREMI  10 , one lumen might include a camera  32  with a lens connected by an optical fiber to a video unit (not illustrated) that displays an anatomical structure to the endoscope/DREMI operator. A secondary optical fiber  34  might be connected to a light source (not illustrated) to illuminate the structure for viewing. Lumens  36  and  38  might be fluid channels for water, air, or the like. Endoscopes often supply fluids to a structure in order to clean and dry the structure to be viewed and/or operated on. These are known endoscopic components.  
         [0024]     A tool channel  40  is provided that allows the forward and rearward movement of DREMI  10  within endoscope  30 . A valve structure (not illustrated) or other known endoscopic feature may be included to prevent fluid flow into channel  40 . Of course, it would also be possible to include more or less lumen to perform additional or different tasks than described above. For instance, it is envisioned that more than one channel could be dedicated to providing a tool that extends past the end of the endoscope.  
         [0025]     As illustrated, distal reticule  18 , secured to coil pipe  14 , is extended beyond the distal end of endoscope  30 . Coil pipe  14  is a coiled wire, typically made from stainless steel or a thin-walled plastic tubing. The coil pipe is diminutive enough to be slidable within channel  40 , but it has a sufficient diameter to allow actuator wire  16  to actuate within the coil pipe. Coil pipes and actuator wires are also used in the endoscopic art.  
         [0026]     Returning to  FIG. 1 , reticule  18  consists of a molded plastic or other suitable material. As illustrated, reticule  18  is rod-shaped and it terminates at its distal end, relative to the coil pipe, at a semispherical cap  42  to which the distal end of wire  16  is anchored by conventional means. Cap  42  is an integral part of reticule  18 . The proximal end of reticule  18  abuts coil pipe  14 . A cap  43  is crimped onto coil pipe  14  and an anchoring portion of reticule  18  in order to secure the reticule to the coil pipe. Cap  43  can provide an optional graduation mark aligned in the direction of the folded reticule&#39;s axis (the graduation mark is illustrated but not labeled). The exact dimensions of reticule  18  are unimportant as the exact size of the DREMI, in general, will be determined by the medical procedure and/or endoscopic equipment in use.  
         [0027]     Reticule  18  has a plurality of distinct body segments wherein each segment can be pivoted relative to any adjacent segment. A pair of upper and lower rulers  44 ,  46  form a substantial part of the length of reticule  18  and are parallel to each other in a folded state. The rulers have a semicircular cross section (as better illustrated in  FIGS. 5 and 6 ). Rulers  44 ,  46  are proximate to the end of coil pipe  14  when reticule  18  is folded. The rulers provide graduations  48  that are placed in 1 mm increments. The graduations can be indentations, inked markings, or the like. They are visible to the DREMI operator via an endoscopic camera when the reticule is in either the folded (parallel to the axis of the endoscope) or unfolded (perpendicular to the axis of the endoscope) states, as will be discussed further below. Rulers  44 ,  46  are adjacent the anchored portion of the reticule.  
         [0028]     Additional body segments include the upper backing  50  and lower backing  52 . These parts of the reticule are adjacent to, and integral with, cap  42  (i.e., the distal end of DREMI  10 ). Backings  50 ,  52  are roughly the same length as upper and lower rulers  44 ,  46 . Further, upper backing  50  is aligned with upper ruler  44  while lower backing  52  is aligned with lower ruler  46  so long as reticule  18  is in the folded state. The upper and lower backings also have semicircular cross sections. When folded, the flat side of each backing contacts the corresponding flat side of the other backing, creating a rod. The rulers are similarly arranged. When folded the backing members and rulers are aligned to create a single rod shape.  
         [0029]     The reticule forms a rod shape that is split down the middle and held together by cap  42  (see  FIGS. 5 and 6 ). The rulers and backings bridge the anchored portion of the reticule to cap  42 . The anchored portion of the reticule are physically joined to the rulers. The rulers are physically connected to the backing members, and the backing members are physically connected to cap  42 . The material between each of these sections is scored, cut, molded or otherwise constructed so as to allow the adjacent sections to pivot relative to each other. For instance, the backings pivot relative to the cap, and the anchor portion of reticule  18  (portion of reticule held to coil pipe by crimping cap  43 ) is also pivotally connected to the corresponding rulers.  
         [0030]     Thus, the reticule has three pivot points on each side of its rod shaped body, identified in the figures as elements  54 ,  55 , and  56 . Actuating slide  22  away from its naturally biased position pulls cap  42  towards the endoscope. This causes reticule  18  to unfold along the pivot points. In this unfolded state, the body segments of the reticule are aligned substantially perpendicular to the axis of an endoscope. The unfolding action is further illustrated in  FIG. 3 , wherein it is illustrated that the middle of the reticule unfolds initially into a diamond shape.  
         [0031]     The fully unfolded reticule is illustrated in  FIG. 4 . As will be obvious to one of skill in the art, the upper and lower rulers are aligned along an axis perpendicular to the axis of coil pipe  14  or endoscope  30 . Graduations  48 , placed at evenly spaced intervals along the upper and lower rulers, would be visible to an endoscopic camera. Backings  50 ,  52  are behind the rulers. The two backings are now aligned end-to-end. The reticule is held in the unfolded state by pressure on cap  42  in the direction of coil pipe  14 . Releasing slide  22  on actuator  12  releases cap  42 . The reticule returns to a folded state due to a natural biasing force. In the folded state, the reticule can be withdrawn into the endoscope.  
         [0032]     A DREMI or endoscopic operator will, therefore, be able to pass DREMI  10  out of an endoscope so the depth of an anatomical structure could be measured while the DREMI is folded. By actuating actuator  12 , the DREMI unfolds into an alignment perpendicular to the line of sight provided by the endoscopic camera. The operator can directly read the length of the same anatomical structure.  
         [0033]      FIGS. 5 and 6  illustrate reticule  18  in further detail. Without the crimping cap  43  or wire  16  holding reticule  18  together, the two semi-spherical halves of the reticule can be spread apart to form one elongated body.  FIGS. 5 and 6  both illustrate the integral relationship of the cap to the backings. The reticule is a single piece of material that is constructed or modified so as to allow for the pivot points  54 ,  55 ,  56 . In one preferred embodiment, reticule  18  is a molded piece of plastic wherein the material joining all the joints  54 ,  55 ,  56  is a thin section of malleable plastic. End views for each Figure are identified as elements  60  and  62 , respectively. The series of graduations  48  along the rulers are clearly evenly spaced. The anchor portion that is normally held by crimping cap  43  is labeled in these figures as element  58 .  
         [0034]      FIG. 6  illustrates the bottom side of the spread apart reticule. An axially arranged channel  64  is provided in what is normally the interior of the reticule  18 . Channel  64  nests with wire  16  when reticule  18  is in the folded state. A mounting aperture  66  in cap  42  is sized and shaped to accept wire  16 . The wire can be anchored to the aperture by conventional means, such as an adhesive, welding, or mechanical connection.  
         [0035]     Assembly of the DREMI is accomplished by molding or otherwise constructing the reticule  18 . Crimping cap  42  is placed over the actuator wire and positioned to partially overlap with the coilpipe. A known actuator is attached to the reticule via the actuator wire. A portion of the reticule is overlapped by crimping cap  42 . A crimping force is placed on the crimping cap to hold the reticule to the coil pipe provided by the actuator. In use, an operator simply engages the actuator to fold and unfold the reticule. Other assembly techniques are available and would be obvious to one of skill in the art.  
         [0036]     While the invention has been described with reference to specific embodiments thereof, it will be understood that numerous variations, modifications and additional embodiments are possible, and all such variations, modifications, and embodiments are to be regarded as being within the spirit and scope of the invention.