Patent Abstract:
A gastroscopic apparatus for inspecting a body channel is described. The apparatus comprises an insertion tube, an operating handle, a dispenser, which is detachably coupled to the insertion tube, a covering sleeve, which is retained within the dispenser, and a mouthpiece, which is provided with a means for arresting the dispenser within the mouthpiece. Upon arresting the dispenser within the mouthpiece and advancement of the insertion tube within the body channel, the covering sleeve extends from the dispenser and deploys around the insertion tube to protect from contamination that portion of the insertion tube, which had passed the dispenser.

Full Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates generally to the field of endoscopy and specifically to flexible endoscopes used for medical examination of an intestinal system during which an insertion tube provided with an optical head is put through the mouth and down the esophagus. An example of possible implementation of the present invention could be a gastroscope for viewing the stomach or duodenum and for removing tissues from these organs. It should be kept in mind, however that the present invention is not limited to gastroscopes and can be implemented in any other endoscopes employed for medical examination of the intestinal system, e.g. in duodenoscopes, sigmoidoscopes, etc.  
       BACKGROUND OF THE INVENTION  
       [0002]     The main components of a modern gastroscopic apparatus comprise a flexible insertion tube fitted at its distal end with an optical head, an operating handle for manipulating the insertion tube during its advancement within the body organ and a system control unit provided with a source of compressed air, water and vacuum to be supplied to the body organ during the gastroscopic procedure. The insertion tube is introduced within a patient&#39;s mouth through a dedicated mouthpiece held by the patient&#39;s teeth. The mouthpiece guides the insertion tube during the gastroscopic procedure.  
         [0003]     Flexible endoscopes in general and gastroscopes in particular are notoriously difficult to clean and disinfect thoroughly, leading to problems of cross-contamination between patients and between patients and staff. These problems can be partially avoided by covering the endoscope with a single-use sleeve, which is discarded after use. The use of a disposable sleeve (also referred to as a sheath) to cover an endoscope is well known in the art.  
         [0004]     Endoscopes commonly have working channels, running from a proximal port outside the body to a distal port at the distal end of the endoscope. When the distal end of the endoscope is inserted into the body organ, the working channel may be used to pass a surgical instrument through to the distal end of the endoscope in order to perform a surgical procedure, such as a biopsy.  
         [0005]     Instruments that are used in this manner become contaminated with biological matter from inside the patient&#39;s body. As the instrument is withdrawn from the body, it spreads the contamination to the interior of the working channel and to the proximal port of the endoscope and eventually to the operator&#39;s hands.  
         [0006]     Therefore it would be very beneficial to prevent spread of contamination originating from the endoscope itself or from the surgical instrument  
         [0007]     Ouchi (US Publication 2003/0097043) describes a cover for preventing contamination of an operating portion of an endoscope. The cover is formed in a bag-like shape for enveloping a total of the operating portion. The cover can prevent exposure to contamination during the endoscopic procedure when the insertion tube is inside the patient. However, during the procedure and in the end of the procedure, the insertion tube is withdrawn from the patient and, since it remains uncovered, the spread of contamination originating from the insertion tube would not be prevented.  
         [0008]     Chinese patent CN 1,486,666 describes an endoscope system fitted with a disposable sheath, which at least at its distal end is made of transparent material. The sheath seals all the inserted portion of the endoscope. Various hard-to-clean, open-ended channels of the endoscope, including working channel for surgical instrument, are arranged outside the insertion tube and are disposed of together with the sheath after single use.  
         [0009]     Still further methods for sheathing an endoscope for protecting it from contamination are described, for example, in Silverstein (U.S. Pat. No. 4,646,722) and Sidall (U.S. Pat. No. 4,741,326), whose disclosures are incorporated herein by reference. These methods attempt to prevent contamination of the endoscope, either by adding disposable working channels external to the endoscope itself (Silverstein) or by adding a disposable liner inside a working channel of the endoscope (Sidall).  
         [0010]     Voloshin (U.S. Pat. No. 6,485,409), whose disclosure is incorporated herein by reference, describes an endoscope, which comprises an endoscopic probe, a bending section for directing the probe within the colon (steering unit), an insertion tube and a flexible covering sleeve or a sheath, which is coupled proximally to the probe. The sleeve is attached to the endoscope in such a manner that its folded section is retained between a cap and an internal spindle located between the insertion tube and the probe head. When inflated, the folded section unfolds over a flange of the internal spindle and an inner portion of the sleeve is pulled in a distal direction. The sleeve at the same time covers the insertion tube and prevents its contamination during the endoscopic procedure.  
         [0011]     Eizenfeld (WO 2004/016299; PCT/IL03/000661), whose disclosure is incorporated herein by reference, discloses an endoscope which employs a flexible inflatable sleeve assisting propulsion of the insertion tube within the body organ. The sleeve is retained in folded condition within a dedicated dispenser. The insertion tube is inserted into a dispenser and is advanced within the body organ. The insertion tube engages the sleeve, which covers the insertion tube and protects it from contamination.  
         [0012]     Bar-Or (WO 2005/110185; PCT/IL05/000426), whose disclosure is incorporated herein by reference, discloses a disposable set which comprises a dispenser for retaining a folded disposable sleeve, which upon inflation unfolds and protects the insertion tube from contamination.  
         [0013]     The above-mentioned references teach how the principle of a disposable covering sleeve can be realized essentially in a colonoscopic apparatus, however they do not disclose how to implement this approach for preventing contamination in a gastroscopic apparatus as well.  
       SUMMARY OF THE INVENTION  
       [0014]     The object of the present invention is to provide a new and improved gastroscopic apparatus, which minimizes the risk of cross contamination to both patient and staff during the gastroscopic procedure.  
         [0015]     Still a further object of the invention is to provide a new and improved gastroscopic apparatus, wherein an insertion tube can be advanced along the esophagus while being protected by a disposable covering sleeve.  
         [0016]     Still a further object of the invention is to provide a new and improved gastroscopic apparatus fitted with a simple arrangement for deployment of a covering sleeve around the insertion tube when it is being inserted in the esophagus and displaced along the esophagus.  
         [0017]     Various embodiments of the present invention can be implemented as a gastroscopic apparatus and as a method for propelling a gastroscope in the esophagus.  
         [0018]     For a better understanding of the present invention as well of its benefits and advantages, reference will now be made to the following description of its embodiments, taken in combination with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]      FIG. 1  is a perspective view of an operation handle of a gastroscopic apparatus of the present invention.  
         [0020]      FIG. 2  is a longitudinal view, partially broken away, of a fragment of the insertion tube coupled to a dispenser.  
         [0021]      FIG. 3A  is a longitudinal view, partially broken away, of the dispenser just before entry into the mouthpiece; and,  FIG. 3B  is an enlarged sectional view of area A of the mouthpiece.  
         [0022]      FIG. 3C  is a longitudinal view, partially broken away, of the dispenser upon entry into the mouthpiece and arresting of the dispenser within the mouthpiece; and,  FIG. 3D  is an enlarged sectional view of area A of the mouthpiece encircled in  FIG. 3C .  
         [0023]      FIG. 4  is an isometric view of a mouthpiece employed in the gastroscopic apparatus of the present invention.  
         [0024]      FIG. 5  shows the insertion tube before insertion into the mouthpiece.  
         [0025]      FIG. 6  shows the insertion tube inserted into the mouthpiece and at the beginning of the gastroscopic procedure.  
         [0026]      FIG. 7  shows the insertion tube at the beginning of the advancement through the mouthpiece into the esophagus and  FIG. 8  shows the entire gastroscopic apparatus and the patient during the gastroscopic procedure. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]     With reference to  FIG. 1  an operation handle  10  of a gastroscopic apparatus of the present invention is shown. The operation handle is of a conventional design and is identical with the operation handle of a standard gastroscopic apparatus in all its functionality for the operator. The gastroscopic apparatus comprises also a system control unit (SCU) and a monitor. Since these components are similar with those of the standard gastroscopic apparatus they are not shown in  FIG. 1 , but are seen in  FIG. 8 .  
         [0028]     The operation handle includes an angulation control knob or wheel  11 , suction and air/water buttons  12 ,  14  for admitting fluid medium into the esophagus and a Y-connector  16  provided with an inlet port  18  and a channel for connecting to respective sources of fluid medium (usually air, water and vacuum). These sources are available at the SCU.  
         [0029]     The operation handle is operatively connected to a proximal end of an insertion tube  20 , through which a guide channel  22  extends. In a preferred embodiment of the invention the guide channel is designed as an integral conduit suitable for receiving a disposable tube with separate lumens for supplying air, water and vacuum. This tube will be referred-to further as multilumen tubing. An example of such multilumen tubing and its description can be found in Bar-Or (WO 2005/110200; PCT/IL05/000428), whose disclosure is incorporated herein by reference. The operation handle is connected also to a system control unit (SCU, shown in  FIG. 8 ) via an umbilical cord  24 , through which extend electrical cables connecting the SCU with the optical head deployed in the distal end of the insertion tube. All above elements are similar to those employed in the conventional gastroscopic apparatuses.  
         [0030]     It is not shown in detail, but one should keep in mind that within the insertion tube are provided various devices, which are necessary for proper functioning of the endoscope. These devices and their arrangement within the insertion tube are known in the art. Among such devices one can mention vertebrae and strings, which can be manipulated by the angulation knob provided at the operation handle.  
         [0031]     Referring now to  FIG. 2  it is shown that at the distal end of the insertion tube  20  an optical head  26  covered by a plastic cap  28  is provided. The plastic cap is defined by a forward butt end and by a cylindrical periphery surface. The butt end is conveniently provided with windows, which are aligned with an optical camera located within the optical head and with a light source of the optical camera. In accordance with a preferred embodiment a CCD camera should be used. The optical head is fitted also with an integrated light source, preferably white LED light source. By virtue of the CCD camera and the LED light source, visualization is much more efficient since there is no need for fiber optics, and thus it is possible to significantly reduce maintenance and repair costs. An example of a suitable optical head provided with the CCD camera and the LED light source can be found in our patent application PCT/IL05/000929 whose disclosure is incorporated herein by reference.  
         [0032]     One should also keep in mind that adjacent the distal section of the insertion tube a bending section is provided. This section enables maneuvering of the distal end of the insertion tube during the endoscopic procedure. The bending section comprises a plurality of vertebrae connected to the strings, which are pullable upon rotation of the angulation knob. By virtue of this provision it is possible to change the vertebrae&#39;s position and thus to control the curvature of the distal end and to navigate the insertion tube during its advancement within the patient.  
         [0033]      FIG. 2  shows still a further component of the gastroscopic apparatus of the invention. This component is a dispenser  30 , which is provided at the distal end of the insertion tube and is used during the gastroscopic procedure. The dispenser is configured as a tubular body through which the insertion tube can pass. The dispenser has a rear end  32 , an elastically flexible forward end  34  and an intermediate portion  36  confined therebetween. At the beginning of the gastroscopic procedure the dispenser is coupled to the insertion tube in such a manner that its rear end  32  is located at the bending section and its forward end  34  elastically embraces the cap. The dispenser is coupled to the insertion tube at the forward end with a possibility that during the gastroscopic procedure the insertion tube can be protracted into or retraced from the dispenser. Tightly put on the cap a snap ring  38  is provided, which allows detachable snap connection between the forward end  34  and the insertion tube. The snap connection at the same time ensures that the insertion tube would be only distally displaceable with respect to the dispenser. The intermediate portion of the dispenser is formed with a couple of diametrically disposed through going openings  40 ,  42 , which function will be explained later on with reference to  FIGS. 3C and 3D .  
         [0034]     Deployed within the dispenser a fixation bushing  44  is provided. This bushing has a flaring entrance opening  46  to pass the insertion tube there through and a conical outside surface  48 , which snugly fits with a mating inwardly facing conical surface  50  at the rear end of the dispenser. The remainder of the bushing is configured as a thin cylindrical tube, which is put on the insertion tube with possibility for relative displacement there between.  
         [0035]     An annular space is defined between intermediate portion  36  of the dispenser and the bushing and a flexible protection sleeve or sheath  52  is deployed in this space. The sleeve is folded within the dispenser as shown in  FIG. 2 , while its proximal end is firmly anchored between conical surfaces  48 , 50 . The sleeve&#39;s distal end passes between the cap and the forward end  34  and is firmly anchored between the cap&#39;s periphery and the snap ring.  
         [0036]     Now with reference to  FIGS. 3A, 3B ,  3 C,  3 D and  4  still a further component of the gastroscopic apparatus of the invention will be described. This component is a mouthpiece  54  depicted in  FIGS. 3A and 4 .  
         [0037]     During the gastroscopic procedure the mouthpiece is held within the patient&#39;s mouth by her or his teeth and the insertion tube is advanced along the esophagus through the mouthpiece, while the dispenser is arrested within the mouthpiece.  
         [0038]      FIG. 3A  also schematically shows the cross-section of the integral guide channel or multilumen tubing with separate lumens  56 ,  58 ,  60  extending there along. Lumens  56 , 58  are of a smaller diameter and they are respectively intended for supplying water for irrigation and air for insufflation. Lumen  60  is of a larger diameter and is intended for introducing surgical tools or for suction.  
         [0039]     As shown in  FIG. 3A and 3B  the mouthpiece is provided with a central body portion  62 , which has a tubular shape. An inwardly facing cylindrical surface  64  of the central body portion defines an opening  66  through which the dispenser can be brought in the mouthpiece. To allow this, the inside diameter of the opening slightly exceeds the outside diameter of the intermediate portion  36  of the dispenser. As will be explained later on, by virtue of this provision the dispenser also can be rotated along its longitudinal axis when it is brought within the mouthpiece.  
         [0040]     One end of the central body portion of the mouthpiece terminates by a flange portion  68 , while the opposite end terminates by a distal, bite portion  70 . The flange portion is directed essentially perpendicularly to the central body portion and has an overall dimension D. The inside diameter of the opening  66  is less than the outside diameter of the rear end  32  of the dispenser. By virtue of this provision when the dispenser is fully inserted within the mouthpiece, the flange portion  68  of the mouthpiece abuts the rear end  32  of the dispenser to limit its axial displacement within the mouthpiece as seen in  FIG. 3C .  
         [0041]     The bite portion is configured with a rim, which slightly widens laterally to ensure reliable holding of the bite portion by the patient&#39;s teeth when the mouthpiece is in the patient&#39;s mouth.  
         [0042]      FIG. 4  shows the flange portion  68  of the mouthpiece in more detail. One can see that it has nearly elliptical configuration defined by two rounded wings  72 ,  74 . The wings are situated diametrically at both sides of the central body portion  62 . To reduce weight of the mouthpiece, respective openings  76 ,  78  are provided within the rounded wings. It is seen also that respective ends  80 ,  82  of an elastic strap are attached to each wing. During the gastroscopic procedure the strap is worn behind the back of patient&#39;s head and holds the mouthpiece more reliably in place within the patient&#39;s mouth.  
         [0043]     Attention is now called again to  FIGS. 3A, 3B ,  3 C and  3 D. These figures show that a protrusion  84  is formed on the inwardly facing surface  64  of the mouthpiece. The protrusion is made of elastically deformable material and has a saw tooth shape defined by a long inclined surface  86  and by a short inclined surface  88 . The inclination angle of the surface  86  is less than inclination angle of the surfaces  88 . The surface  86  is inclined to allow advancement of the dispenser within the mouthpiece only in the distal direction. Dispenser  30  is allowed to advance along the mouthpiece until protrusion  84  enters in one of the through-going opening  40  or  42 , depending on the relative angular disposition of the dispenser within the mouthpiece. As soon as protrusion  84  is aligned with one of the openings, it elastically snaps and the dispenser becomes arrested within the mouthpiece. This situation is shown in  FIGS. 3C and 3D . To separate the dispenser from the mouthpiece one should rotate the dispenser so as to elastically deform the protrusion and to remove it from the opening. Rigidity of dispenser material as well as configuration and dimension of the protrusion are selected to allow elastic deformation of the protrusion resulting in snapping engagement and disengagement between protrusion and openings depending whether dispenser is advanced within the mouthpiece, or rotated.  
         [0044]     In practice the dispenser, the sleeve and the mouthpiece are cheap disposable items, which are discarded at the end of the endoscopic procedure after evacuating the insertion tube from the esophagus. The dispenser and the mouthpiece could be made from a rigid or semi rigid plastic material, e.g. polypropylene, polyethylene, ABS, etc.  
         [0045]     The sleeve could be typically made from a flexible biocompatible plastic, such as polyamide, having a thickness of about several tens of microns.  
         [0046]     In  FIGS. 5-8  are shown the consecutive stages of a gastroscopic procedure during which the gastroscopic apparatus of the present invention is used in practice.  
         [0047]      FIG. 5  presents an initial stage of the gastroscopic procedure when the mouthpiece  54  is held within the patient&#39;s mouth being ready to receive the distal end of the insertion tube along with the dispenser  30  coupled thereto. For the sake of simplicity the other components of the gastroscopic apparatus are not shown.  
         [0048]      FIG. 6  shows the next stage of the gastroscopic procedure, during which the distal end of the insertion tube has been brought towards the opening of the mouthpiece and then advanced there into. As explained earlier by rotating the dispenser within the mouthpiece one of the openings  40 ,  42  can be brought in alignment with the protrusion  84  to allow snapping thereof on the intermediate portion  36  of the dispenser and arresting within the mouthpiece.  
         [0049]     Still further stage of the gastroscopic procedure is depicted in  FIG. 7 , showing how the insertion tube has been pushed further through the dispenser  30 . The dispenser is arrested within the mouthpiece and remains stationary. The proximal end of the sleeve remains stationary too, since it is firmly secured at the rear end of the dispenser. Insertion tube  20  is pushed distally through the dispenser along the esophagus  90  and urges the distal end of the sleeve to move distally together with the insertion tube, since it is firmly secured between the cap and the insertion tube. Distal end of the sleeve extends automatically from the dispenser, unfolds and covers a portion  92  of the insertion tube, which has passed through the dispenser. It can be appreciated that the unfolded sleeve deploys around the insertion tube and reliably protects it from any contamination matter originating from the esophagus.  
         [0050]      FIG. 8  depicts a still further stage of the advancement of the insertion tube. It is seen that at this stage a major portion of the insertion tube has passed the dispenser and is located within the esophagus. This portion is covered by protective sleeve  52 . Distal end of the insertion tube is approaching the stomach  94 , which interior can be observed by the optical head. Other components of the gastroscopic apparatus remain outside the patient. Among these components are proximal portion  96  of the insertion tube  20  and operation handle  10  with Y-connector  16 , working channel  22 , umbilical cord  24 , the SCU and the monitor.  
         [0051]     It is seen that proximal portion  96  of the insertion tube still has not been advanced in the dispenser. This portion would be available if it is required to advance the insertion tube along the esophagus still further, through the stomach  94  within a duodenum  98 .  
         [0052]     At the end of gastroscopic procedure the insertion tube and the sleeve are withdrawn from the patient.  
         [0053]     According to one embodiment of the invention the dispenser remains arrested within the mouthpiece during the withdrawal. When the insertion tube is being withdrawn, the sleeve bunches and remains in the patient&#39;s mouth outside the dispenser. At the end of withdrawal the compactly bunched sleeve is located in the mouth adjacent the bite portion. Now the dispenser is disengaged from the mouthpiece and the insertion tube together with the bunched sleeve is taken out. Thereafter the insertion tube is separated from the sleeve and the sleeve along with the dispenser is disposed of. The mouthpiece is removed from the patient&#39;s mouth and is disposed of too.  
         [0054]     According to an alternative embodiment the dispenser is disengaged from the mouthpiece before the withdrawal and the insertion tube is evacuated from the esophagus together with the sleeve being extended and deployed there along. The insertion tube is removed from the mouthpiece together with the dispenser and with the covering sleeve. Thereafter the insertion tube is separated from the sleeve and the sleeve along with the dispenser is disposed of. The mouthpiece is removed from the patient&#39;s mouth and is disposed of too.  
         [0055]     It can be readily appreciated that by virtue of the present invention it is possible to minimize the risk of cross contaminations to both patients and staff during the gastroscopic procedure and to make the gastroscopic procedure cleaner and safer.  
         [0056]     Furthermore, the present invention eliminates the need for reprocessing equipment and helps the facility to save on capital expenses (purchase of additional scopes), labor costs and costs of disinfectants, cleaning tools and scope maintenance.  
         [0057]     The present invention allows for increased patient throughput as a result of faster procedures with shorter down time for the scope. This, in its turn, allows to schedule more procedures and therefore to increase revenues for both physician and facility.  
         [0058]     The gastroscopic apparatus of the present invention has very simple construction, which is reliable and at the same time remains very similar to a standard apparatus, thus enabling an extremely short learning time to the physician to achieve optimal performance.  
         [0059]     It should be appreciated that the present invention is not limited to the above-described embodiments and that one ordinarily skilled in the art can make modifications without deviation from the scope of the invention, as will be defined in the appended claims.  
         [0060]     For example, more that two openings could be made in the dispenser and more than one tooth could be made in the mouthpiece.  
         [0061]     The openings could be made in the mouthpiece instead of the dispenser and the teeth can be arranged in the dispenser instead of the mouthpiece.  
         [0062]     Other types of detachable connections between the mouthpiece and the dispenser could be employed instead of a snap connection.  
         [0063]     When used in the following claims, the meaning of terms “comprise”, “include”, “have” and their conjugates is “including but not limited to”.  
         [0064]     It should also be appreciated that the features disclosed in the foregoing description, and/or in the following claims, and/or in the accompanying drawings may, both separately and in any combination thereof, be material for realizing the present invention in diverse forms thereof.

Technology Classification (CPC): 0