AU2007216622B2 - Endoscope - Google Patents

Description

S&F Ref: 765305AUD2 AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name and Address Techmin Pty Limited, of Applicants: an Australian company, ACN 001 261 829, of 18 Loyalty Road, North Rocks, New South Wales, 2151, Australia Sydney West Area Health Service, a body organised under the Area Health Services Act (1986) amended 1993 (NSW), of Office of Commercialisation, Eastern Cluster Executive Offices, Westmead Hospital, Westmead, New South Wales, 2145, Australia Actual Inventor(s): Philip Dey Peter Klineberg Murray Stokan Per Gorm Gunther Nielsen Address for Service: Spruson & Ferguson St Martins Tower Level 35 31 Market Street Sydney NSW 2000 (CCN 3710000177) Invention Title: Endoscope The following statement is a full description of this invention, including the best method of performing it known to me/us: 5845c(938208_l ) Endoscope Field of the Invention The present invention relates to an endoscope having a light source mounted thereon. The invention has particular application to laryngoscopes and will be described 5 hereinafter with reference to this application. However, it will be appreciated that the invention also has other applications. Background of Invention Laryngoscopes are used by physicians, in particular anaesthetists, to perform laryngoscopy and visualise the larynx. Once in place, the anaesthetist can more readily 10 insert endotracheal tubes and the like into the trachea of the patient. The design of laryngoscopes has been relatively unchanged for many decades, with the scope normally comprising a handle and a detachably mounted hook-on blade which are connected together in a substantially L-shaped configuration. Dental trauma during laryngoscopy is a relatively common complication. Such is dental trauma normally results from excess pressure being applied to the upper front teeth of the patient, which can act as a fulcrum. While learning laryngoscopy it is difficult for the trainee and supervisor to estimate how much pressure is being applied to the maxillary incisors. During difficult intubations, even experienced larygnoscopists can apply excessive force. 20 While laryngoscopes having pressure sensors have been described in the patent literature (e.g. US 5536245), such sensors have not been seen in use by the present inventors. This is postulated by the present inventors to be due to complications in the manufacture and/or use of hitherto known designs. The present application is directed to a pressure sensor that can be used with or 25 on a laryngoscope that addresses the perceived complications in the art.

2 During visual examination, a light bulb mounted on the scope can be illuminated to assist in illuminating the area being examined by the anaesthetist or surgeon during use. Such bulbs have typically comprised an incandescent bulb drawing power from one or more batteries in the handle of the scope. 5 Due to concerns raised by the possibility of cross-contamination arising from the use of laryngoscopes on different patients, laryngoscope blades are now routinely sterilised following use on a single patient. Laryngoscope handles are also routinely decontaminated by being wiped with a bacterial solution. This requirement has significantly increased the stock of laryngoscope blades and handles that must be held in 1o store by any one hospital. Following repeated sterilisations, the performance of the laryngoscope also decreases eventually to the point where it must be discarded. Enquiries by the present inventors have determined that the light bulbs mounted on laryngoscopes do not typically last more than three to five sterilisations of the device and must, therefore, be routinely replaced. This requirement to purchase, sterilise, store and is continually replace light bulbs on laryngoscopes represent a significant cost for a busy hospital or other medical facility. The present application is directed to laryngoscope that overcomes or at least ameliorates at least one of the disadvantages of the prior art, or at least provides a useful alternative. 20 Any discussion of the document, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context of the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general acknowledge in the field relevant to the present invention as it existed in Australia before the priority date of 25 each claim of this application. Summary of the Invention Throughout this specification the word "comprise", or variations such as "comprise" or "comprising", will be understood to imply the inclusion of a stated 3 element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. According to a first aspect, the present invention provides an endoscope comprising: s a first disposable portion for insertion into a body cavity; and a second portion adapted to be removably coupled to the fist portion and having at least one light emitting diode (LED) mounted thereon for providing illumination of the body cavity. The endoscope can comprise a laryngoscope. In another arrangement, the 10 endoscope can comprise an otoscope. In a particular arrangement, the endoscope is disposable after a single use. In this arrangement, the endoscope may be formed from a plastics material. The laryngoscope can comprise a handle and a blade. The blade may have a proximal end and a distal end with its proximal end attachable to the handle. The 15 orientation of the blade to the handle can be fixed. Alternatively, the blade orientation can be adjustable. In one arrangement, the light emitting diode (LED) can comprise a gallium arsenide (GaAs) LED. Other suitable light emitting diodes having suitable luminous intensities can be utilised. In one arrangement, the luminous intensity may be at least 20 5600mcd, at least 6000mcd, or at least between 10000 and 15000mcd. In a further arrangement, more than one light source can be mounted to the endoscope. In one arrangement, the LED can be mounted to the blade of the laryngoscope. The LED can be mounted to the handle of the laryngoscope. In this case, the LED may 25 be mounted to the handle at or adjacent its first end. The LED may be non-removable mounted to the handle.

4 The blade can include a light transfer means adapted to a transfer light emitted by the LED from its position on the handle through at least a portion of the blade. In one arrangement, the light transfer means has a first end at or adjacent the proximal end of the blade. A second end of the light transfer means can be positioned on the blade at a 5 location distal the proximal end of the blade. The second end of the light transfer means may be at or adjacent the distal end of the blade or positioned back along the blade at a desired distance from its distal end. In one arrangement, the light transfer means can comprise a cylindrical member. Members having other suitable shapes can be envisaged. The member may be straight, to however, non-straight members could be utilised. In one arrangement, the member can be formed from an acrylic material. The light transfer means may serve to direct the light emitted from the LED through the blade and out into the body cavity or orifice into which the laryngoscope has been inserted. In a further arrangement, the endoscope can incorporate a switching means for 15 use in activating and/or deactivating the light source. In one arrangement, the switching means can be operable by a user of the endoscope. In yet another arrangement of the laryngoscope, the LED may be activated when the blade is mounted to the handle. In this case, the LED may be mounted to the handle at or adjacent its first end. The LED may be non-removably mounted to the handle. 20 In this arrangement, the switching means can comprise an actuable member mounted on the handle that is activated by a complementary actuating member on mounting of the blade to the handle. For example, the handle and blade can have complementary bayonet type fittings to allow the blade to be attached to the handle. In still another arrangement, the switching means can utilise an induction coil 25 mounted within the handle. The blade can also incorporate a coil or magnetic component. On attachment of the blade to the handle, the current flowing through the coil in the handle is modified. This modification can be detected by circuitry in the handle and lead to illumination of the light source.

5 The coil in the handle and the blade, can be comprised of at least two turns of electrically conductive wire. The coil in the handle may be tuned to parallel resonance by a capacitor that is part of the circuitry. The induction coil in the handle can also be used as a means of inductively s charging the batteries stored within the handle of the device. A charger can receive the handle and inductively charge the batteries within the handle. Each charger can be used to charge more than one handle. The inductive coupling between the handle and the coil can also aci: as a means of transferring signals from the transducer, when present, to the circuit, when the circuit is io located within the handle. The handle can have a cavity for containing the circuitry for operation of the light source as defined above. The power source for the light source and circuitry may be housed within the cavity. The power source may comprises one or more batteries. Each battery may be non-removable from the handle. The batteries can also be rechargeable to 15 allow re-use of the batteries. The handle may be sealed to prevent fluid ingress therein. According to a second aspect, the present invention provides a method of intubating a patient comprising the step of using the endoscope as defined in the first aspect above. According to alternative aspect, there is provided a laryngoscope comprising a 20 blade and handle, a transducer being attached to the blade, the transducer comprising a circuit having a switch means and an indicator means, the switch means comprising a layer of an electrically conductive polymeric material that is deformable into contact with an electrically conductive contact of the circuit, on presence of a predetermined level of incident pressure, to complete the circuit and so activate the indicator means. 25 In this aspect, the block of electrically conductive polymeric material may be formed from a carbon-loaded silicone rubber. The block may have an underside having at least one channel formed therein, each of said at least one channel overlaying a respective 6 one of said electrically conductive contact, the channel being deformable on presence of said predetermined incident pressure into contact with said contact. Each of said at least one contact can comprise a metal track formed on a printed circuit board. The metal tracks can comprise part of the circuit that is closed when the s block contacts the track so as to allow power to activate the indicator means. In this aspect, the indicator means may comprise an alarm means actuable on closure of the circuit. The alarm means may comprise a visual means and/or an audible means. The visual means can comprise one or more lights or light emitting diodes 10 (LED). In another arrangement, the visual means can comprise a readout giving a measure of relative or absolute pressure detected by the transducer. The audible means can comprise a buzzer, bell or the like. The frequency and/or volume of the buzzer can vary in response to changes in incident pressure measured by the transducer. For example, the frequency and/or volume of the buzzer can increase in response to increasing Is pressure. According to a further aspect, there is provided a sensing means comprising a transducer adapted to be mounted to a blade of a laryngoscope, and an indicator means, the transducer comprising at least a layer of a polymeric material that undergoes a change in resistivity in response to incident pressure thereon, the change in resistivity being 20 useable by the indicator means to provide an output at least indicative of the incident pressure. According to another aspect, there is provided a laryngoscope comprising a blade and handle, a transducer being attached to the blade, and an indicator means, the transducer comprising at least a layer of a polymeric material that undergoes a change in 25 resistivity in response to incident pressure thereon, the change in resistivity being useable by the indicator means to provide an output at least indicative of the incident pressure.

7 In one arrangement of the above aspects, the transducer can be formed at least in part of a material that permanently deforms on contact with the teeth of a patient. The degree of permanent deformation of the material of the transducer may be proportional to the degree of pressure applied to the transducer by the teeth of the patient. In one s arrangement, the permanent deformation comprises depression of said material in the region of contact between the transducer and the teeth of the patient. In this arrangement, the depth of a depression is indicative of the degree of pressure applied to the teeth of the patient, with the deeper the depression, the greater the applied pressure. According to yet another aspect, there is provided a sensing means adapted to be io attached to a blade of a laryngoscope, and an indicator means adapted to output at least a relative determination of incident pressure detected by the transducer, the transducer being formed at least in part of a material that permanently deforms on contact with the teeth of a patient. In a particular arrangement of this aspect, the degree of permanent deformation 15 of said material is proportional to the degree of pressure applied to the transducer by the teeth of the patient. In one arrangement, the permanent deformation comprises depression of said material in the region of contact between the transducer and the teeth of the patient. In this arrangement, the depth of a depression is indicative of the degree of pressure applied to the teeth of the patient, with the deeper the depression, the greater the 20 applied pressure. In an arrangement of the above aspects, a plurality of transducers can be packaged together. For example, a plurality of transducers can be mounted by a release adhesive to a common backing layer. When required, a transducer can be peeled from the backing layer, used, and then discarded. 25 In the above aspects comprising at least a polymeric material comprising the transducer, the polymeric material can be one or more layers of the polymeric material sold under the name Velostat.TM. by the company 3M.Tm., ie. a carbon impregnated polyolefin. Other materials having equivalent or similar properties can also be utilised.

8 The electrical resistivity of the material may be inversely proportional to incident pressure, the incident pressure causing compression in at least a region of the transducer. The layer of Velostat may be sandwiched between respective layers of an electrically conductive material. Each sandwich layer may be formed from the same 5 material. The sandwich layers can be maintained in a substantially parallel spaced relationship by the layer of Velostat.TM. The electrically conductive material can be a metal, such as copper sheet. The sandwich layers act as respective electrodes for the transducer. In an arrangement, the sandwich layers can act as the material that permanently deforms on contact with the teeth of a patient. 10 The transducer can further include a layer of relatively resiliently flexible material mounted to at least one face thereof. This layer can be selected from the group comprising a foam, an elastomeric material and a polymeric material. The resiliently flexible material layer can have a layer of adhesive on one or both faces. The face of the layer that becomes the inwardly facing layer following mounting of 15 the transducer may have a removable backing layer over the adhesive. The backing layer of the adhesive may be removed to allow mounting of the transducer to the blade of the laryngoscope. The transducer may further include a protective layer on at least one face of the transducer. The protective layer may be relatively electrically insulating. The layer may 20 be transparent to allow viewing of the electrically conductive layer therebeneath. A layer of adhesive can be used to bond the protective layer to the transducer. Electrically conducting wires may be electrically connected to each of the electrodes of the transducer. The wires may be used to provide electrical connection between the transducer and the indicator means. The wires may be formed from a metallic 25 material, such as copper or aluminium wire. Each of the wires may be surrounded by an electrically insulating material for a majority of its length. The electrical insulation may be removed where the wire comes into contact with its respective electrode and where it makes electrical connection to the indicator means.

9 The wires may be connected to each of the electrodes using electrically conductive adhesive tape or an electrically conductive adhesive epoxy. Other suitable bonding techniques, including crimping and soldering can be envisaged. The indicator means may comprise an electrical circuit. The transducer may be a 5 component of the electrical circuit. The electrical circuit may use a voltage comparator to detect the change in resistance of the transducer in response to incident pressure. Where the transducer has a layer that decreases in electrical resistivity in response to an increase in incident pressure and vice versa, the circuit may note the change in resistance. When the resistance drops to or below a predetermined threshold, the circuit may activate an to alarm means that is part of the circuit. The alarm means can comprise a visual means and/or an audible means. The visual means can comprise one or more lights or light emitting diodes (LED). In another arrangement, the visual means can comprise a readout giving a measure of relative or absolute pressure detected by the transducer. The audible means can comprise a buzzer, is bell or the like. The frequency and/or volume of the buzzer can vary in response to changes in incident pressure measured by the transducer. For example, the frequency and/or volume of the buzzer can increase in response to increasing pressure. The electrical circuitry of all of the aspects can be powered by a power source, such as one or more batteries or mains power. The circuitry can include a light or light 20 emitting diode (LED) that indicates the operational status of the circuit (eg. On/Off). This light or LED can be a different colour or multicolour to that used as the visual means. Where the circuitry relies upon the exceeding of a predetermined threshold, the threshold for activation of the alarm means can be variable and can be set by the user prior to use or even adjusted during use. In certain instances, such as where intubation is 25 being carried out by trainees, the threshold may be set relatively low to ensure that the alarm means, for example, is activated in response to a relatively small incident pressure being applied to the patient's teeth during use. As the user becomes more experienced with the use of a laryngoscope, the threshold can be increased such that the alarm means 10 only operates in instances where relatively excessive pressure is being applied to the teeth of the patient. In a still further arrangement, the circuit of any of the above aspects can include a memory means to allow recording of pressure data measured by the transducer. The 5 memory means may automatically, or on request, transmit the recorded data to a playback means such as a personal computer, printer or monitor to allow visualisation of the pressure readings over time. In particular arrangements, the transducer may not be able to be removed from the blade of the laryngoscope. The blade, including the transducer, may be disposable. 10 The blade with the transducer mounted thereon may be packaged in a sterile container following manufacture and is sterile when removed from the package and mounted to the laryngoscope handle. In a further arrangement of the above aspects, a light source, such as a high intensity light emitting diode (LED) can be mounted to the transducer. The LED can be is mounted to the distal end of the transducer and so provide illumination of the larynx during use. According to a further aspect there is provided a method of intubating a patient comprising at least the steps of: using a laryngoscope having a sensing means, according to the above aspects; 20 and using the indicator means to monitor the pressure applied to the teeth of the patient during use of the laryngoscope. Brief Description of the Drawings By way of example only, particular exemplary arrangements of the invention are 25 now described with reference to the accompanying drawings, in which: 11 Fig. I is a simplified side elevation view of one arrangement of a transducer according to the present invention; Fig. 2 is a schematic view of one arrangement of a transducer and indicator means according to the present invention; 5 Fig. 3 is a depiction of a patient undergoing laryngoscopy using a laryngoscope having a transducer according to the present invention removable attached thereto; Fig. 4 is a depiction of a patient undergoing laryngoscopy using a laryngoscope having a light emitting diode (LED) mounted thereon; Fig. 5 is a cut-away perspective view of the handle and blade of the 10 laryngoscope; Fig. 6 is another cut-away perspective view of the laryngoscope of Fig. 5; Figs. 7a-7c are various perspective views of the laryngoscope blade; and Figs. 8a and 8b are side elevational and inverse plan views of a block of material for use as part of a switch for another arrangement of a sensing means according to the 15 present invention. Preferred Mode of Carrying out the Invention One arrangement of a sensing means having a transducer according to the present invention is generally depicted as 10 in Figs I to 3. As depicted in Fig. 3, the transducer 10 is adapted to be removable adhered to a 20 blade 41 of an endoscope, in the form of a laryngoscope 40. While the depicted transducer can be removable attached to the blade 41, it should be appreciated that a laryngoscope having a non-removable transducer attached thereto is also encompassed within the scope of the present invention. The device further includes an indicator device depicted schematically as 11 in 25 Fig. 2 which is described in more detail below.

12 In the depicted arrangement, the transducer 10 is formed of a layer of polymeric material 12 sold under the name Velostatm by the company 3Mm, i.e. a carbon impregnated polyolefin. The electrical resistivity of this layer 12 is inversely proportional to incident pressure, the incident pressure causing compression in at least a region of the 5 transducer 10. The layer 12 of VeolostatTm is sandwiched between respective copper electrodes 13 that are maintained in a substantially parallel spaced relationship by the layer 12 of Velostat m . While copper electrodes are preferred due to the permanent deformation suffered by the material on being brought into contact with the patient's teeth, other io electrically conductive materials could be utilised. As depicted, the transducer 10 can further include a layer 14 of relatively resiliently flexible material mounted to at least one face thereof. Layer 14 can be selected from the group comprising a foam, an elastomeric material and a polymeric material. The resiliently flexible material layer 14 can have a layer of adhesive on one or is both of its faces. The face 15 of the layer 14 that becomes the inwardly facing layer following mounting of the transducer 10 the blade 41 preferably has a removable backing layer (not depicted) over the adhesive.

13 The transducer 10 further has a protective layer 16 on what becomes its outward face. The depicted protective layer 16 is relatively electrically insulating and transparent to allow viewing of the electrode 13 therebeneath. A layer of adhesive can be used to bond the protective layer 16 to the electrode 5 13. The depicted transducer 10 is packaged in a sterile container following manufacture and should be sterile when removed from the package and mounted to the laryngoscope blade 41. A plurality of transducers 10 can be 1o packaged together and delivered ready for Individual use. For example, while not depicted, a plurality of transducers 10 can be mounted by a release adhesive to a common backing layer. When required, a transducer can be peeled from the backing layer, used, and then discarded. 15 Electrically conducting wires 17 are connected to each of the electrodes 13 of the transducer 10. The wires 17 provide electrical connection between the transducer 10 and the indicator device 11. The depicted wires 17 are connected to each of the electrodes 13 using 20 electrically conductive adhesive tape or an electrically conductive adhesive epoxy. Other suitable bonding techniques, Including crimping and soldering can be envisaged. The Indicator device 11 comprises an electrical circuit. The transducer 25 10 Is a component of this electrical circuit. The depicted Indicator device 11 uses a voltage comparator to detect the change in resistance of the transducer 10 in response to Incident pressure. As the layer 12 decreases In electrical resistivity In response to an Increase In Incident pressure and vice versa, the circuit detects the change in resistance. When the resistance drops to or below 30 a predetermined threshold, the circuit activates a buzzer and/or Illuminates a light emitting diode mounted in the indicator device 11. While not depicted, the indicator device can include a readout giving a measure of relative or absolute pressure detected by the transducer 10. The 35 frequency and/or volume of the buzzer varies in response to changes in 14 incident pressure measured by the transducer. In this example, the frequency and/or volume of the buzzer increases in response to Increasing pressure. The electrical circuitry of the depicted indicator device 11 is powered by 5 one or more batteries. The circuitry includes an LED that indicates the operational status of the circuit (eg. On/Off). This LED is a different colour to that described above. The indicator device also includes an On/Off switch that allows a user to connect/disconnect power to the circuitry when desired. 10 The threshold of the circuitry is variable and can be set by the user prior to use or even adjusted during use. In certain instances, such as where intubation is being carried out by trainees, the threshold may be set relatively low to ensure that the Indicator means operates in response to the pressure being applied to the patient's teeth during use. As the user becomes more 15 experienced with the use of a laryngoscope, the threshold can be Increased such that it only operates in instances where relatively excessive pressure is being applied to the teeth of the patient. In use, the transducer 10 wil firstly be removed from its sterile packaging 20 and adhered to the blade 41 as depicted in Fig. 3. The wires 17 can then be electrically connected to the indicator device 11. During use, any pressure applied to the patient's teeth by the blade 41 is detected by the transducer 10. The circuitry within the Indicator device 11 can 25 be set such that the LED and/or buzzer of the indicator device 11 only activates when a certain threshold is reached. Following completion of the laryngoscopy, the blade 41 is removed from the mouth. The transducer 10 can then be peeled from the blade 41 and 30 discarded. Figs. 8a and 8b depict an alternative component for use as a switch for activating the indicator means 11. The component comprises a block 60 of an extrinsically conductive material, namely a carbon-loaded silicone rubber. The 35 block 60 has a plurality of channels 61 formed in the underside thereof. On the occurrence of an Incident pressure on the top side 62 of the block 60, one or 15 more of the channels will deform sufficiently to brig at least a portion of the block into contact with a metal track of a printed circuit board that can pass therebeneath (not depicted). 5 The block 60 and metal track act together as a switch to control the supply of a power to an indicator means 11 used in association with the switch. When one or more of the channels 61 collapse, the circuit is closed and power is provided to the indicator means 11 so activating an alarm means, such as a buzzer and/or light. 10 Fig. 4 depicts another embodiment of a laryngoscope according to the present Invention that can be used by physicians, in particular anaesthetists, to perform laryngoscopy and visualise the larynx. Once in place, the anaesthetist can more readily insert endotracheal tubes and the like into the trachea of the 15 patient. The laryngoscope according to the present invention is generally depicted as 40 in Figs 4-7c. 20 The laryngoscope 40 depicted in Fig. 4 is disposable and comprises a handle 42 and a blade 41. In this embodiment, both the handle 42 and blade 41 are formed from a plastics material. Suitable materials include polycarbonate, or a copolymer from the ABS (acrylonitrile-butadiene-styrene) family. 25 The depicted blade 41 is removably attachable to the handle 42 through a bayonet fitting 43. The blade 41 has a proximal end 44 and a distal end 45 with its proximal end 44 attachable to the handle 42. In the depicted embodiment, the orientation of the blade 41 to the handle 42 once attached is 30 fixed. In another embodiment, the blade 41 could be constructed so as to be adjustable relative to the handle 42. The laryngoscope 40 has a light source 46 mounted thereon for providing Illumination of the cavity or orifice, during use. The light source 46 35 comprises a high intensity gallium arsenide (GaAs) light emitting diode (LED) supplied by Nichia Corporation of Tokushima 774-8601, Japan. Other suitable 16 light emitting diodes having suitable luminous intensities, including LEDs from other suppliers can be utilised. In the depicted embodiment, the LED 46 is non-removably mounted to 5 the handle 42 of the laryngoscope 40. The blade 41 has a straight cylindrical acrylic light pipe 47 incorporated therein that transfers light emitted by the LED 46 from its position on the handle 42 through the blade 41 to an outlet 48. The light pipe 47 serves to direct the 10 light emitted from the LED 46 through the blade 41 and out into the body cavity or orifice into which the laryngoscope 40 has been inserted. The laryngoscope Incorporates a switching means for use in activating and/or deactivating the LED 46. In this embodiment, the LED 46 Is activated 15 when the blade 41 is mounted to the handle 42 and remains Illuminated while ever the blade 41 is attached to the handle 42. The handle 42 has a cavity 49 for containing the circuitry 51 for operation of the LED 46 as defined above. The power source for the LED and circuitry 20 51 is also housed within the cavity 49 and comprises a series of batteries 52. The batteries 52 In the depicted embodiment are not removable from the handle 42. They are, however, rechargeable to allow re-use of the handle in assocIation with a blade. 25 In a typical use, a new blade 41 will be removed from sterile packaging and attached to a handle 42. On attachment, the LED 46 will Illuminate and the laryngoscope 40 can be used and positioned by the anaesthetist as depicted in Fig. 4. Following use, the blade 41 can be removed from the handle 42 and disposed of. As, in the depicted embodiment, there is either no or minimal 30 circuitry or wires mounted within the blade 41, the blade 41 is readily disposable at minimum cost. It will be appreciated that in another embodiment, the blade 41 could incorporate other features, including circuitry and other devices, if desired. If necessary, the handle 42 can be sterilised ready for re use with a new blade 41 when required. 35 17 It will be appreciated by persons skilled In the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be 5 considered in all respects as Illustrative and not restrictive.

Claims (13)

1. An endoscope comprising: a first disposable portion for insertion into a body cavity; and a second portion adapted to be removably coupled to the fist portion and having at least 5 one light emitting diode (LED) mounted thereon for providing illumination of the body cavity.

2. An endoscope in accordance with claim 1, wherein the endoscope is a laryngoscope and wherein the first portion is a disposable blade and the second portion is a handle. 10

3. An endoscope in accordance with claim I or claim 2, further comprising one or more light radiating devices mounted on the first portion.

4. An endoscope in accordance with any one of claims 1 to 3, wherein the first portion has a light transfer conduit adapted to transfer light emitted by the LED from its position on the second portion along at least a part of the first portion to one or more light is radiating devices on the first portion.

5. An endoscope in accordance with claim 4, wherein the light transfer conduit is adapted to transfer light emitted by the LED from a first end at or adjacent a proximal end of the first portion to a second end positioned on the first portion at a location distal the proximal end of the first portion. 20

6. An endoscope in accordance with any one of the preceding claims, wherein the light transfer conduit is an acrylic cylindrical light transfer tube.

7. An endoscope in accordance with any one of the preceding claims, wherein the LED is activated when the first portion is coupled to the second portion and deactivated when the first portion is uncoupled from the second portion. 25

8. An endoscope in accordance with claim 7, further comprising: a switch to ensure that the LED remains illuminated while the first portion is coupled to the second portion but that the LED is extinguished upon uncoupling of the first portion from the second portion; the switch utilising an induction coil mounted on the second portion and a coil or other 30 component capable of carrying an induced electrical current on the first portion; the induction coil on the second portion and the coil or other component on the first portion interacting such that modification in current flowing through the coil on the second portion caused by proximity of the induction coil or other component on the first portion is detected by circuitry in the second portion which modifies the on/off state of 35 the LED; 19 wherein, none of the components of the switch has exposed contacts or moving parts external to the second portion.

9. An endoscope in accordance with claim 8, wherein the coil in the second portion and the coil in the first portion are comprised of at least two turns of electrically s conductive wire, and the coil in the second portion is tuned to parallel resonance by a capacitor.

10. An endoscope in accordance with claim 8 or claim 9, wherein the induction coil in the second portion is adapted to inductively charge a rechargeable battery stored within the second portion when brought into proximity with a complimentary charger adapted to io receive the second portion.

11. An endoscope in accordance with any one of claims 8 to 10, further comprising: a pressure sensing switch on the first portion adapted to be activated by excessive pressure between the first portion and teeth of a patient; the induction coil in the second portion being adapted to transfer signals from the pressure 15 sensing switch on the first portion to electronic alarm components in the second portion.

12. A method of intubating a patient comprising the step of using an endoscope in accordance with any one of claims I to 11.

13. An endoscope substantially as hereinbefore described with reference to any one embodiment, as that embodiment is shown in the accompanying drawings. 20 DATED this sixteenth Day of April, 2009 Techmin Pty Limited Sydney West Area Health Service Patent Attorneys for the Applicant 25 SPRUSON & FERGUSON