Abstract:
An electronic endoscope ( 2 ) of the type including: a distal end ( 14 ) including an illumination element and an electronic image acquisition member; a probe ( 12 ), one of the ends of which is connected to the distal end; and control elements ( 10 ) connected to the other end of the probe, characterized in that the probe includes a plastically malleable portion ( 20 ) suitable for preserving, under the effect of its own weight when the endoscope is in use, the shape which has been conferred on it by an operator, the malleable portion carrying the distal end of the endoscope.

Description:
The present invention relates to an electronic endoscope of the type comprising: a distal end comprising an illumination means and an electronic image acquisition means; a probe, one of the ends of which is connected to the distal end; and control means connected to the other end of the probe. 
     BACKGROUND OF THE INVENTION 
     Some respiratory pathologies of the larynx or pharynx of a member of the Equidae, and in particular of a racehorse, can be diagnosed only by an endoscopic examination carried out in the course of a dynamic test, using an endoscope, preferably an electronic endoscope. 
     According to the prior art, the control means of an electronic endoscope comprises a light source producing a luminous flux which is guided along the probe as far as the distal end by means of an optical fibre. The illumination means of the distal end comprises lenses enabling the luminous flux received from the optical fibre to be distributed on the zone to be examined. The light source of the known electronic endoscopes has a large space requirement and requires a high-power electric current generator, which also has a large space requirement. Consequently, the electronic endoscopes according to the prior art are fixed instruments. 
     This is why the dynamic test is carried out on dedicated premises equipped with an endoscopy installation comprising a fixed electronic endoscope and a specific treadmill on which the racehorse to be examined is placed. 
     Use is made of a pliable electronic endoscope, the probe of which is soft and non-self-supporting. This mechanical characteristic of the probe is used to position the distal end. More precisely, the distal end is introduced via the nostrils and then pushed into the animal&#39;s sinuses, in order to be placed in the animal&#39;s throat, facing the zone to be examined. The probe which carries the distal end then abuts the walls of the sinuses and of the cavity to be inspected. 
     However, in this test environment, the animal is not really under normal training conditions. The trauma of being placed on a treadmill distorts the animal&#39;s behaviour, which reduces the value of such an examination accordingly. 
     In addition, an endoscopy installation comprising a treadmill is extremely expensive. Furthermore, since this installation is fixed, it is necessary to transport the racehorse to the examination premises, which represents an additional cost when these premises are at a long distance from the training centre. 
     Finally, the image obtained is not of high quality because the distal end carried by the soft probe and comprising the electronic image acquisition means is displaced relative to the zone to be examined in the course of the dynamic test and the animal&#39;s movements. In extreme cases, such as a sudden movement of the animal&#39;s head, the distal portion may come into contact with the mucous membranes. 
     SUMMARY OF THE INVENTION 
     The object of the invention is therefore to provide a solution to the above-mentioned problems by proposing an electronic endoscope enabling an endoscopy to be carried out under normal conditions, for example racehorse training conditions, while ensuring a good image quality. 
     To that end, the invention relates to an electronic endoscope of the above-mentioned type, characterized in that the probe comprises a plastically malleable portion capable of preserving, under the effect of its own weight when the endoscope is in use, the shape which has been given to it by an operator, the malleable portion carrying the distal end of the endoscope. 
     According to particular embodiments of the invention, the electronic endoscope comprises one or more of the following features, taken in isolation or in accordance with any technically possible combination:
         the illumination means comprises at least one LED.   the control means comprises a battery as a means of generating electric current suitable for supplying the endoscope with electrical power, the endoscope thus being rendered autonomous.   the malleable portion comprises at least one rod which is produced from a suitable malleable material and a cross-section of which has suitable dimensions, so that the rod confers the desired plasticity on the malleable portion.   the malleable portion comprises two rods produced from a material which conducts the electric current, and the two rods enable the battery to be connected electrically to the illumination means of the distal end.   the control means comprises a means for emitting and transmitting radio waves in order to communicate with a corresponding means for emitting and transmitting radio waves which is arranged at a distance.       

     the control means comprises a processing means enabling the signals generated by the electronic image acquisition means to be processed in real time in order to produce images, it being possible for the images produced to be displayed in real time on a display means connected to the corresponding means for emitting and transmitting radio waves which is arranged at a distance.
         the endoscope is suitable for carrying out an endoscopic examination on a racehorse in the course of a normal training session thereof.       

     the rod is produced from a copper alloy, preferably comprising 90% by weight of copper, and has a diameter of from 1.7 to 2.5 mm, and preferably from 1.75 to 2.25 mm.
         the endoscope comprises a halter provided with a means for securing the probe, the securing means preferably comprising at least one clip enabling the probe to be secured by clipping.       

    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention and its advantages will be better understood on reading the following description which is given purely by way of example and with reference to the appended drawings, in which: 
         FIG. 1  is a diagrammatic representation of the electronic endoscope according to the invention in the examining position on a racehorse; 
         FIG. 2  is a front view of the clip of the means for securing the endoscope of  FIG. 1 ; 
         FIG. 3  is a cross-section through the malleable portion of the endoscope of  FIG. 1 ; and 
         FIG. 4  is an axial section through the head of the distal end of the endoscope of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  illustrates diagrammatically the electronic endoscope  2  according to the invention. The electronic endoscope  2  is shown in position on the head of a horse  4 . It is desired to examine the larynx  6  of horse  4  in the course of a dynamic test carried out under the normal conditions of a training session. 
     The electronic endoscope  2  comprises control means  10 , a probe  12 , and a distal end  14 . The distal end  14  is connected mechanically and electrically to the control means  10  by way of the probe  12 . 
     The distal end  14  comprises a head  16  and an articulated portion  18 . The head  16  comprises a means for illuminating the cavity to be examined, and also an electronic image acquisition means suitable for generating an electrical video signal. As will be described in detail in the description of the head  16  with reference to  FIG. 4 , the illumination means comprises several electroluminescent diodes, or LEDs, and the electronic image acquisition means comprises a charge transfer sensor, or CCD sensor. 
     The articulated portion  18 , secured to the rear of the head  16 , connects the head  16  to one of the ends of the probe  12 . The articulated portion  18  comprises first and second displacement means enabling the head  16  to be oriented mechanically in two mutually perpendicular directions. 
     The control means  10  will now be described in detail. 
     Since the illumination means of the electronic endoscope  2  according to the invention is constituted by LEDs, the control means  10  do not comprise a light source, unlike the prior art. Furthermore, the LEDs consume a small amount of electrical power, so that the control means  10  of the endoscope  2  comprise a generator of electric current which is a battery  72  having small dimensions. Consequently, the control means  10  are compact and transportable. They are carried by the subject to be examined. In the case of a racehorse, the control means  10  can be placed in the saddle, in a rucksack carried by the rider or, as shown in  FIG. 1 , secured to an arm  66  of the sulky drawn by the horse  4 . The electronic endoscope according to the invention weighs less than 5 kg. 
     The control means  10  comprise a casing  70  for the mechanical and electrical connection of the probe  12 ; first and second drive means  71  for operating the first and second displacement means, respectively, of the articulated portion  18 ; the battery  72  for the supply of electric current to the endoscope  2 ; a processor  74  suitable, inter alia, for processing the video signal transmitted from the electronic image acquisition means; and a storage means  76  enabling the images decoded by the processor  74  to be recorded in real time. 
     The control means  10  also comprise a means  80  for emitting and receiving radio signals. The emitting and receiving means  80  is to communicate with a corresponding emitting and transmitting means  82  based on the ground and at a remote distance. The corresponding emitting and transmitting means  82  is, for example, connected to a computer  83  having a screen  84 , and a keyboard  86 , and constituting a control and monitoring interface for the operator. In particular, the operator watches in real time, on the screen  84 , the image acquired by the electronic endoscope  2 , throughout the installation of the endoscope  2  and in the course of the dynamic test. 
     The first and second drive means for operating the first and second displacement means, respectively, of the articulated portion  18  may assume the form of first and second thumb wheels on the control casing  70 . These first and second thumb wheels are used by the operator to orient the head  16  of the endoscope in a suitable manner during an initial stage of installing the endoscope, before carrying out the dynamic test. Preferably, the first and second drive means are actuators  71  suitable for being remote-controlled by the operator by means of the computer  83  and the radio communication means  80  and  82 . 
     The probe  12  is connected, at one of its ends, to the articulated portion  18  of the distal end  14  and is coupled, at the other end, to the connecting casing  70  of the control means  10 . The function of the probe  12  is to connect the control means  10  electrically to the illumination means and to the image acquisition means of the head  16 , and to connect the control means  10  mechanically to the articulated portion  18 . 
     Furthermore, the function of the probe  12  of the electronic endoscope  2  according to the invention is to hold the distal end  14  in a predefined position inside the cavity to be examined. For that purpose, the probe  12  comprises, in succession along its length, a malleable portion  20 , a connecting element  22  and a passive portion  24 . The malleable portion  20  extends between the articulated portion  18  of the distal end  14  and the connecting means  22 . The passive portion  24  extends between the connector  22  and the connecting casing  70 . 
     The malleable portion  20  of the probe  12  will now be described in detail with reference to  FIG. 3  which shows a cross-section thereof. The malleable portion  20  is locally of a cylindrical shape about an axis A. It has a diameter of less than  1  cm. It is delimited externally by a tubular sleeve  28  composed of a plastics material, such as, for example, PVC. The face oriented radially towards the inside of the sleeve  28  is reinforced by a helical metal strip  30 . The latter constitutes a reinforcement of the malleable portion  20  permitting deformation by bending in an axial plane. 
     Inside the volume delimited by the helical metal strip  30 , the malleable portion  20  of the probe  12  comprises a first pair of cables  31  and  32  which are to be coupled, on the one hand, to the first mechanical displacement means of the articulated portion  18  and, on the other hand, to the first drive means of the control means  10  in order to orient the head  16  in the first direction. The malleable portion  20  also comprises a second pair of cables  33  and  34  which are to be coupled, on the one hand, to the second mechanical means of the articulated portion  18  and, on the other hand, to the second drive means of the control means  10  in order to orient the head  16  in the second direction. 
     The probe  12  also comprises an irrigation duct  36  enabling air and/or water to be brought from an inlet orifice  37  located on the connecting casing  70  to an outlet orifice  35  located on the head  16  of the distal end  14 . The irrigation duct  36  therefore extends through the passive portion  24 , the connector  22 , the malleable portion  20 , the articulated portion  18  and the head  16 . 
     The malleable portion  20  of the probe  12  comprises at least one resiliently malleable rod. In the embodiment described, the malleable portion  20  comprises a first rod  37  and a second rod  38 . The first and second rods  37  and  38  are cylindrical and their respective axes C and D are arranged parallel with the axis A. The function of the first and second rods  37  and  38  is to confer on the malleable portion  20  the mechanical characteristic of being both plastically malleable and rigid: to be more precise, the malleable portion  20  is plastically malleable because it is capable of being deformed during the application of reasonable stresses, that is to say, stresses which can be generated by the muscular force of an operator, and then of keeping the shape thus given by the operator while the deformation stress has ceased to be applied; the malleable portion  20  is rigid in the sense that it keeps the shape given by the operator in the course of the use of the endoscope, that is to say, the malleable portion  20  has a sufficient rigidity with respect to the stresses generated during the dynamic test, by the weight and the accelerations of the malleable portion  20 . 
     Preferably, the first rod  37  and/or the second rod  38  is/are produced from a malleable material. 
     The function of the first and second rods  37  and  38  is also to conduct the electric current from the battery  72  to the illumination means of the head  16 . Preferably, the first rod  37  and/or the second rod  38  is/are then produced from a material which conducts the electric current. 
     In the currently preferred embodiment, the first and second rods  37  and  38  are composed of a metal material, preferably a copper alloy. 
     For an electronic endoscope according to the invention suitable for carrying out an endoscopic examination on a racehorse, the malleable portion  20  is placed on the animal&#39;s head in such a manner that it projects, beyond a securing point P, over a length of approximately 1 meter. The first and second rods  37  and  38  are produced from an alloy of 90% by weight of copper and have a diameter of from 1.5 to 2.5 mm, and preferably from 1.75 to 2.25 mm. The first and second rods  37  and  38  do not have to have the same diameter. 
     It will be appreciated that, in the passive portion  24  of the probe  12 , which portion is flexible without preserving its shape, first and second conventional electrical wires are substituted for the first and second rods  37  and  38  of the malleable portion  20 . The first and second electrical wires are connected electrically, on the one hand, to the first and second rods  37  and  38  and, on the other hand, to the battery  72 , via the connecting casing  70 . 
     Finally, the malleable portion  20  comprises a video cable  40  arranged, for example, along the axis A. The video cable  40  is to transmit the video signal generated by the electronic image acquisition means of the head  16  to the processing means  74  of the control means  10 . The video cable  40  therefore extends from the electronic image acquisition means to the connecting casing  70 . 
     The electronic endoscope  2  comprises means for securing it to the subject to be examined. In the case of a racehorse, the probe  12  is secured to a specific halter  42  comprising a clip  44  shown in detail in  FIG. 2 . The steel clip  44  is riveted on to the leather halter  42 . The clip  44  is configured in such a manner that the probe  12  is secured by clipping. To be more precise, the clip  44  comprises two lateral arms  45 . In an upper section of the clip  44 , the two lateral arms  45  spread apart from each other in such a manner as to provide the clip  44  with a guide section  46  in the shape of a “V” which is to help to guide the probe  12  when it is being secured. Then, in an intermediate section, the two arms  45  are close to each other in order to form a necked section  47 , the width of which is smaller than the diameter of the probe  12 . Finally, in a lower section, the two arms  45  are configured in the shape of arcs of a circle, the diameter of which corresponds to that of the probe  12 , in order to define a section  48  for holding the probe in position. The probe is brought into abutment with the two lateral arms  45  in the region of the necked section  47 . The operator inserts the probe  12  by force between the two lateral arms  45  which move apart resiliently from each other until the probe  12  can pass through the necked section  47  and be accommodated in the holding section  48 . Once in position in the holding section  48 , the probe  12  can rotate about its axis A in such a manner that the operator can, for example, align the first direction of displacement of the head  16  of the endoscope  2  in the vertical direction. 
     Referring now to  FIG. 4 , the head  16  of the electronic endoscope  2  will be described in detail. It will be observed that such an endoscope head can be reused irrespective of the above-mentioned characteristics of the endoscope. The head  16  comprises a housing  50  having a cylindrical shape about an axis B. The rear edge  52  of the housing  50  comprises a shoulder which is abutted by the tubular articulated portion  18 . The front edge  54  of the housing  50  carries a translucent wall  56  closing the front of the housing  50 . The wall is composed, for example, of plexiglass. The translucent wall  56  is curved in such a manner as to form a hemispherical cap projecting axially beyond the front edge  54  of the housing  50 . 
     In the interior volume of the housing  50 , the head  16  comprises an illumination means constituted by at least one LED  58  and preferably by six LEDs  58 . The LEDs  58  are supplied with electric current by the battery  72 , via the connecting casing  70 , the first and second electrical wires of the passive portion  24 , the connector  22 , the first and second rods  37  and  38  of the malleable portion  20  of the probe  12  and electrical connectors in the region of the articulated portion  18 . The LEDs  58  are selected to produce a luminous flux characterized by a temperature of 6000°, which corresponds to natural light, so that the images obtained by means of the endoscope  2  are of high quality. In the embodiment described, six LEDs  58  are arranged regularly along a ring having an axis B. Thus, the intensity of the luminous flux produced by the head  16  is very uniform in the conical illumination field. A LED  58  of oblong shape is arranged parallel with the axis B in a bore  59  provided in the internal face  57  of the translucent wall  56 . Thus, a LED  58  is placed in front of the front edge  54  of the opaque housing  50 . The conical illumination field therefore has a wide opening of the order of 140°. The wall  56  is selected to be translucent in order to diffuse the light generated by the various LEDs  58  and to improve the uniformity of the illumination produced. Since the efficiency of the illumination means used in the head  16  of the endoscope  2  according to the invention is very high, it will be appreciated that there is no longer any need to use lenses to concentrate the luminous flux generated. 
     The head  16  also contains an electronic image acquisition means. This involves a CCD sensor  60 , an objective lens  61  and the low-level acquisition electronics required to generate a video signal. The video signal generated is transmitted to the processor  74  via a suitable connector in the articulated portion  18 , the video cable  40  extending along the probe  12  and the connecting casing  70 . The CCD sensor  60  is accommodated in an axial recess  62  extending through the translucent wall  56 . The axial recess  62  is closed in the region of the external face  64  of the translucent wall  56  by the objective lens  61  which has a flat external diopter. The CCD sensor  60  is located along the axis B, behind the objective lens  61 , but in front of the LEDs  58 . Optionally, the axial wall of the recess  62  is opacified so that the CCD sensor is not disturbed by the light produced by the LEDs  58 . 
     The irrigation duct  36  of the probe  12  continues into the distal end  14  and extends through the translucent wall  56 . It terminates in a nozzle  37  placed on the external face  64  of the translucent wall  56 . An internal duct of the nozzle  37  forms an elbow at 90° relative to the axis of the irrigation duct  36  and is oriented in such a manner as to project air and/or water onto the objective lens  61  of the electronic image acquisition means via an orifice  35 . 
     The electronic endoscope according to the invention therefore enables an endoscopic image to be produced while the subject is under normal conditions. 
     Once positioned, the electronic endoscope according to the invention enables a good-quality image to be obtained thanks to the illumination means which generates a high and uniform luminous power, an articulated portion enabling the image acquisition means to be displaced in such a manner as to centre the zone to be examined. 
     The distal end of the electronic endoscope is suspended inside the cavity to be imaged but does not oscillate in the course of the dynamic test. It follows the movements of the horse&#39;s head and there is no risk that it will come into contact with the mucous membranes of the cavity under inspection. The malleable portion can be configured by the operator in such a manner as to follow the anatomical curvature of the ducts moved through to gain access to the cavity to be inspected. 
     The person skilled in the art will appreciate that, since the electronic endoscope according to the invention is free from optical fibres, it can be deformed in such a manner as to adopt any curvature without this having any influence on the quality of the image obtained.