Patent Description:
Instruments such as endoscopes and otoscopes may be employed to examine and perform surgery on ears. Some such instruments may be held against the surgeon's eye to view and magnify the subject whereas other such instruments have a camera that allows the subject to be viewed on a video display such as a computer monitor.

Effective access and visualisation are key to safe surgical procedures. In this respect, traditional ear surgery employing microscopic visualisation suffers from the disadvantage of a narrow field of view looking down into the ear canal. As a result, there can be poor visualisation of disease in the middle ear in regions that are difficult to access, such as the sinus tympani and facial recess. Whilst trans-canal surgery may be performed through a speculum by using a microscope and specialised surgical instruments, this again suffers from a narrow field of view.

Thus, to improve the field of view, it is often necessary to expose the middle ear and attic area by performing a mastoidectomy. However, as the ears are surrounded by dense bone, mastoidectomy procedures are associated with increased operating times, potentially significant complications, longer hospital stays and protracted recovery.

Another disadvantage of microscopic visualisation in ear surgery is the substantial size of a surgical microscope. This compromises the surgeon's dexterity, restricts the space available for surgical intervention and may have negative ergonomic consequences for the surgeon when using the microscope.

Endoscopic ear surgery has become a growing clinical speciality, not least because of the drawbacks of microscopic visualisation. In comparison to a surgical microscope, an endoscope offers improved visibility and allows less invasive surgery. However, the ear presents particular challenges to the use of an endoscope, with a requirement for the image-sensing part of the endoscope to be as small as possible while maintaining image quality and allowing multiple angles of view. Another challenge relates to cleaning, especially to keeping a lens of the endoscope clean in use, and more generally to cleaning or reconditioning the endoscope for reuse.

In use, tissue or other contaminants adhering to the lens of an endoscope can obscure vision. Consequently, the endoscope may have to be removed from a subject's ear canal repeatedly during surgery for cleaning. This interrupts and prolongs the surgical procedure and increases the risk of errors or inadvertent injury to the patient.

In relation to reuse, there is a risk that an endoscope could be contaminated with prions that may be present in the ear canal. Contamination with the wrong type of prions could endanger a patient's life. Even cleaning and sterilisation processes used in industry cannot remove certain types of contamination such as prions; in this respect, prions cannot be killed as they are not living organisms. Currently, therefore, the World Health Organisation recommends that all instruments used in surgery are discarded after surgery and so are single use wherever possible.

In view of this and other risks, single-use endoscopes for ear surgery have appeared on the market. Indeed, there is now a significant trend for hospitals and manufacturers to move from a model of reuse and maintenance of endoscopic equipment to single-use endoscopy. This trend has been driven to some extent by the inability of in-hospital sterilisation to sterilise equipment fully, hence reducing confidence in the system.

<CIT> describes an endoscope with a shaft and an interchangeable head. The head is detachably connected to the distal end of the shaft at a coupling point. A change in image quality is apparent if the head becomes loosened.

<CIT> describes a video camera system in which the camera head is powered at least in part by electrical energy converted from optical energy provided by a light source. In one implementation, communication between the camera head and control circuitry occurs by means of a wireless communications interface.

<CIT> describes an in-vivo monitoring camera system that includes a camera support tube, a camera unit, a control system and a display apparatus.

<CIT> describes an endoscope comprising an elongated rigid shaft and an optical imaging system arranged at a distal end of the shaft for receiving light from an observation area. The optical imaging system is pivotable with respect to the shaft about a first pivot axis transverse to a longitudinal axis of the shaft. The optical imaging system is also pivotable with respect to the shaft about a second pivot axis that is spaced from the first pivot axis and is also transverse to the longitudinal axis of the shaft.

Unlike simple single-use hospital equipment, such as scalpel blades and syringes, single-use endoscopes are large and generate significant amounts of medical waste. Medical waste is typically incinerated, rendering materials irrecoverable. In the case of instruments containing electronics, this can include precious metals or rare earth metals. The result is a waste of valuable resources and potentially a negative impact on the environment.

At first sight, moving from a single-use system to a circular economy system could be seen as a solution to this problem. For a manufacturer of single-use instruments, moving to a circular economy system would firstly involve recovering used instruments from a hospital in a reverse logistics operation. This recovery step would be followed by: dismantling the instruments; identifying components that can be reused and cleaning them; discarding components that cannot be reused and replacing them with new components; assembling a new instrument from the reused and new components; and packing and sterilising the new instrument ready for distribution. However, this process is not feasible as an alternative to single-use endoscopy without incorporating special design features in the endoscope and in the processes used in the circular economy system.

The invention addresses how a surgical instrument may be designed for integration into a circular economy system in which at least a substantial portion of the instrument can be reused safely and cost-effectively, with minimal waste. The inventive concept also embraces a method by which a surgical instrument can be reconditioned for reuse under a circular economy system.

More generally, the invention also improves prior solutions to provide a panoramic endoscope for ear surgery that is compact, reliable and easy to keep clean in use and that provides highly-effective visualisation.

Embodiments of the invention describe how a camera of an endoscope can be integrated into a rotating head to satisfy the requirement of enabling multiple angles of view. Ideally, the rotating head can turn through <NUM>°. This makes it convenient to clean the lens of the camera by rotating the head and hence the lens past a useful viewing angle and over a wiper blade that removes debris from the lens. Elegantly, this allows one simple mechanism to solve two of the major challenges of endoscopic ear surgery.

To allow an endoscope to operate in this way, the camera unit of the rotating head is an integrated module that incorporates a lens, an image sensor and data transmission provisions. Data may be transmitted wirelessly from the rotating head to a supporting probe structure of the endoscope or to a control unit outside the endoscope. A wireless solution has the advantage of negating wired data connections that could otherwise limit rotation of the head.

Electrical power must also be delivered to the rotating head to power the camera module and any other electrical systems such as illumination LEDs, which commonly are found alongside chip-on-tip image sensors in endoscope designs. Again, this should ideally be done in a way that does not limit rotation of the head.

One solution for delivering electrical power to a rotating head involves the use of rotating or sliding contacts on or around the axis of rotation, where the head is joined to the supporting probe of the endoscope. This requires a robust sealing arrangement to insulate the live contacts from moisture in the ear and from saline solution used in surgery, which is electrically conductive. Another solution is to deliver power wirelessly or electromagnetically, for example in a manner akin to an inductive charging unit. However, implementing either of these solutions remains challenging due to the compactness that is required of an endoscope for ear surgery.

The narrowness of the ear canal determines that, optimally, the outer diameter of the probe and the rotating head should be no greater than <NUM>. Wireless power delivery requires a coil in the rotating head that, in this context, could significantly restrict the space available for other components in the head, notably the camera module itself.

The same size constraints also have a significant impact on image quality as they dictate that the image sensor of the camera must be small in area, typically smaller than <NUM> x <NUM>. This in turn means a small pixel size; and with higher resolution, the pixel size gets smaller still. A problem then ensues because smaller sensor pixels are less sensitive to light than larger pixels. This results in a darker and lower-quality image than would be delivered by a larger sensor, all other things being equal. To counteract this, a larger optical aperture or lens can be used to capture more light but this has the knock-on effect of a reduced depth of field. Indeed, in sufficiently compact optical systems, the depth of field can become so restricted as to be unusable for surgery. Ultimately, what is needed to offset the small size of the system is better illumination. This can require the provision of bigger and more powerful LEDs or the use of a remote light source and optical fibres or other light transmission features.

Against this background, the invention resides in a medical scope as defined in claim <NUM> that comprises: an elongate body; an imaging head supported by and rotatably movable relative to a mount of the body about an axis of rotation extending from the mount, the imaging head including a light emitter for illuminating a field of view of the imaging head; and a light path extending from the body parallel to the axis of rotation and through the imaging head to the light emitter, the light path including a light inlet of the imaging head opposed to a light outlet of the body. The imaging head is preferably cantilevered from the mount.

Conveniently, the light inlet and the light outlet may be mutually opposed across a mounting interface, such as a pivot coupling at which the imaging head is movably attached to the mount.

Where the imaging head contains an image sensor, the imaging head may further comprise a photovoltaic generator arranged such that impingement of light generates electrical power for the image sensor. The imaging head may further comprise a data transmitter powered by the photovoltaic generator to transmit image data from the image sensor to a receiver outside the imaging head.

The imaging head may also comprise a light guide in the light path, configured to direct a portion of light received from the body onto the photovoltaic generator and another portion of light received from the body to the light emitter. The light guide may, for example, comprise a filter that is configured to divide the light received from the body into said portions to be directed onto the photovoltaic generator and toward the light emitter.

Where the light inlet and the light outlet are disposed on said axis of rotation, the light guide may be disposed between the mount and the image sensor in a direction parallel to that axis. The light emitter may also be disposed between the mount and the image sensor in a direction parallel to the axis of rotation, at a position spaced radially from the axis of rotation.

The imaging head may comprise encapsulation around the image sensor. That encapsulation may include a disassembly interface at which the image sensor is preferentially separable from the light emitter. The disassembly interface may, for example, comprise at least one point of weakness in the encapsulation. The disassembly interface may also, or instead, comprise a protective strip embedded along a cutting line in the encapsulation.

The present invention also concerns a method of illuminating a field of view of an imaging head of a medical scope as defined in claim <NUM>, wherein the head is rotatably movable relative to a supporting body of the scope about an axis of rotation extending from the body. The method comprises conveying light along a light path from a light outlet of the body parallel to said axis of rotation to a light inlet of the imaging head and then through the imaging head to be emitted from the imaging head.

Elegantly, as noted above, an image sensor of the imaging head may be powered with electricity generated within the imaging head from at least a portion of the light conveyed along the light path.

Light travelling along the light path within the imaging head may be filtered to separate that light into components for power generation and for illumination, respectively. At least one of those components of the light may be varied, for example in intensity, relative to another of those components of the light to enable independent adjustment of power generation and/or illumination.

Embodiments of the invention deliver light longitudinally through a supporting structure to a rotating endoscope head. Light is used as a mechanism for power delivery to a chip-on-tip endoscope for ear surgery.

In some embodiments, sealed capsules are used to protect components designed for disassembly in a circular economy system. Provision may be made for daisy-chaining for transmission of light, power or data between the capsules.

In summary, the present disclosure provides an endoscope, for example for ear surgery, that comprises an elongate body and an imaging head supported by and movable relative to a mount of the body about an axis of rotation extending from the mount. A light path extends from the body parallel to the axis of rotation and through the imaging head to a light emitter for illuminating a field of view of the imaging head. The light path includes a light inlet of the imaging head opposed to a light outlet of the body, for example across a mounting interface at which the imaging head is movably attached to the mount. The imaging head also includes a photovoltaic generator by which light from the body generates electrical power for an image sensor of the imaging head.

Referring firstly to <FIG> of the drawings, a distal end portion of an endoscope <NUM> comprises a body in the form of an elongate stem, shaft or probe <NUM> that supports a rotating imaging head <NUM>. The head <NUM> houses an integrated camera module <NUM> and a light emitter <NUM> disposed beside the camera module <NUM> to illuminate the field of view. The probe <NUM> extends along a longitudinal axis <NUM>. The head <NUM> turns relative to the probe <NUM> about an axis of rotation <NUM> that extends orthogonally with respect to the longitudinal axis <NUM>. The camera module <NUM> has a field of view that extends radially with respect to the axis of rotation <NUM>. Thus, the camera module <NUM> can be oriented through multiple angles of view by turning the probe <NUM> around its longitudinal axis <NUM> and by turning the head <NUM> around its axis of rotation <NUM>. In <FIG>, the camera module <NUM> and the adjacent light emitter <NUM> are shown at an angle of <NUM>° to the longitudinal axis <NUM>.

The head <NUM> is generally cylindrical, extending along and being rotationally symmetrical about the axis of rotation <NUM>. The head <NUM> is supported for rotation by a mount in the form of a distally-extending cantilever arm <NUM> of the probe <NUM>, offset laterally from the longitudinal axis <NUM>. The cantilever arm <NUM> supports the head <NUM> at only one end or side of the head <NUM>. This beneficially maximises the size of the head <NUM> within the constrained diameter of the endoscope <NUM>, eases assembly and disassembly, provides greater freedom to arrange the internal components of the head <NUM> and leaves the free end or side of the head <NUM> available for additional lateral imaging if desired.

In this example, rotation of the head <NUM> is driven by a continuous drive cable <NUM> that extends from a drive mechanism (not shown) within the probe <NUM> and wraps around the head <NUM>. The drive cable <NUM> is retained in a pulley groove <NUM> encircling the axis of rotation <NUM> adjacent to the end of the head <NUM> adjoining the cantilever arm <NUM>. Rotation of the head <NUM> relative to the probe <NUM> about the axis of rotation <NUM> is unconstrained and so can exceed <NUM>° in this example.

The probe <NUM> supports a distally-facing resilient wiper blade <NUM> that has an elongate free edge extending parallel to the axis of rotation <NUM>. The wiper blade <NUM> bears against the proximal side of the head <NUM>. As the head <NUM> is rotated past the wiper blade <NUM>, the wiper blade <NUM> cleans debris from the head <NUM> to prevent that debris obscuring the field of view of the camera module <NUM> or blocking illumination from the light emitter <NUM>.

Although not shown here, an outer lens of the camera module <NUM> may sit slightly proud of the surrounding outer surface of the head <NUM> so that the wiper blade <NUM> only impinges on the outer lens as the head <NUM> turns and does not drag on the remaining circumference of the head <NUM>. Thus, there may be a small radial clearance between the wiper blade <NUM> and the head <NUM> except where the protruding outer lens of the camera module <NUM> bridges that gap on encountering the wiper blade <NUM>.

In this embodiment, as will now be explained, the light emitter <NUM> is the distal end of an illumination conductor or light path that conveys light along the probe <NUM> to the head <NUM> from a remote light source. This solution is favoured in view of size constraints within the head <NUM> and because it allows easier variation of the light spectrum, for example by use of different light sources, which may be useful for tissue identification and in other respects.

Unlike transmission of electricity, transmission of light from the probe <NUM> into the head <NUM> does not require a complex contact or sealing arrangement. However, the problem of providing electrical power to the camera module <NUM> within the head <NUM> remains. In this embodiment, the solution is to generate the necessary electricity within the head <NUM> from a portion of the incoming light. In this way, a single efficient mechanism avoids the problem of sealing electrical contacts and better addresses the challenge of providing an illumination solution within a restricted space than the alternative of integral LEDs in the head. The mechanism shown also facilitates the abovementioned rotation and cleaning solutions.

The cross-sectional views of <FIG> and <FIG> show internal features that define light transmission paths within the endoscope <NUM>.

<FIG> is a view from a direction orthogonal to both the longitudinal axis <NUM> and the axis of rotation <NUM>. This shows that light from an external light source (not shown) travels distally through an optical medium <NUM> in the probe <NUM>, in a direction generally parallel to the longitudinal axis <NUM>. On reaching the distal end portion of the probe <NUM>, the light encounters a mirror or preferably a prism <NUM> mounted in the cantilever arm <NUM>. This directs the light through an optical medium <NUM> in a direction generally parallel to the axis of rotation <NUM> to enter the head <NUM> via the sliding interface or gap at the junction between the cantilever arm <NUM> and the head <NUM>. The optical medium <NUM> therefore serves as a light outlet from which light is conveyed or transmitted across the interface or gap to impinge on the head <NUM>.

<FIG> also shows that the cantilever arm <NUM> comprises a spigot <NUM> that is engaged within a complementary socket of the head <NUM> to support the head <NUM> for rotation relative to the cantilever arm <NUM>. The optical medium <NUM> extends within the spigot <NUM> along the axis of rotation <NUM> to the interface between the cantilever arm <NUM> and the head <NUM>, thereby to emit light into the head <NUM> across that interface. In this example, the spigot <NUM> is substantially coplanar with the groove <NUM> in the exterior of the head <NUM> that accommodates the drive cable <NUM>.

It will be apparent from <FIG> that the head <NUM> further comprises a light guide <NUM> behind the light emitter <NUM>. Conveniently, the pulley groove <NUM> that receives the drive cable <NUM> and the socket that engages the spigot <NUM> of the cantilever arm <NUM> are integral with the light guide <NUM>, for example as part of the same component or with internal features encapsulated within external structures.

The light guide <NUM> is disposed between the camera module <NUM> and the cantilever arm <NUM>. In other words, the cantilever arm <NUM>, the light guide <NUM> and the camera module <NUM> are disposed in succession along the axis of rotation <NUM>. Thus, the light guide <NUM> defines part of the interface between the head <NUM> and the cantilever arm <NUM> and receives the light from the optical medium <NUM> within the spigot <NUM> of the cantilever arm <NUM>. The light guide <NUM> therefore serves as a light inlet of the head <NUM> that receives light conveyed or transmitted from the light outlet of the cantilever arm <NUM> across the interface or gap at the junction between the cantilever arm <NUM> and the head <NUM>.

On entering the head <NUM>, the incoming light is split into two portions by the light guide <NUM>. A first portion of the light impinges on a mirror or preferably a prism <NUM> of the light guide <NUM> and is thereby redirected radially away from the axis of rotation <NUM>. That first portion of the light, thus redirected, is then conveyed through an optical medium <NUM> to the light emitter <NUM>, where it exits the head <NUM> to illuminate the field of view of the camera module <NUM>.

A second portion of the light is directed through the light guide <NUM> to impinge on a photovoltaic cell <NUM> that thereby generates electrical power for the electronic components of the camera module <NUM>. In this example, the photovoltaic cell <NUM> is conveniently integrated into the camera module <NUM> but in principle, the photovoltaic cell <NUM> could be separate from the camera module <NUM>.

Reference is now also made to <FIG>, which is a view from a direction orthogonal to the longitudinal axis <NUM> and along the axis of rotation <NUM>, in longitudinal section through the camera module <NUM>. This shows that the camera module <NUM> preferably has a stacked configuration. Specifically, the camera module <NUM> suitably comprises a commercially-available image sensor <NUM>, onto which a lens barrel <NUM> and a lens <NUM> are mounted. The image sensor <NUM> has BGA (ball grid array) connections that are electrically connected to a power IC (integrated circuit) <NUM> to convey power to the image sensor <NUM> and to convey image data from the image sensor <NUM>. The image sensor <NUM> could include image processing circuits, in which case fewer connections may be required to transmit image data to the power IC <NUM>.

The power IC <NUM> preferably includes the photovoltaic cell <NUM> and power control circuity to power the image sensor <NUM> and wireless data transmission circuitry implemented on a data IC <NUM>. The power IC <NUM> also passes through data from the image sensor <NUM> to the data IC <NUM>. The data IC <NUM> preferably includes an antenna and circuitry to transmit data in packets as required by wireless transmission protocols.

To minimise the power required for wireless data transmission, the data IC <NUM> of the camera module <NUM> conveniently transmits data from the image sensor <NUM> over a very short range, in this example to a wireless receiver <NUM> located in the probe <NUM> near the distal end of the probe <NUM>.

Turning now to <FIG>, this shows a variant of the embodiment shown in <FIG> in which like numerals are used for like features. This variant differs by the addition of a filter or filter layer <NUM> applied to the prism <NUM> within the light guide <NUM> of the head <NUM>. In this variant, the camera module <NUM> is powered by light that is tuned or filtered to a specific wavelength or spectrum, preferably outside the visible light spectrum. The filter layer <NUM> allows that specified light to pass through to the photovoltaic cell <NUM> of the camera module <NUM> while deflecting the remaining light to provide illumination via the light emitter <NUM>. This allows independent control of the power transmitted to the camera module <NUM> and the visible light used for illumination of the target area, for example by varying the intensity or other parameter of one component of the supplied light relative to the other component of that light. More generally, filtering of the light can be done inside or outside the head <NUM> or the probe <NUM>.

<FIG> shows how the embodiment of <FIG> may have features to facilitate reuse of key components in a circular economy system. Again, like numerals are used for like features.

In view of the aforementioned problem of prion contamination, any structure defining an external surface or other surface of the endoscope <NUM> that could come into contact with organic material cannot be reused and must be removed from the device while maintaining the integrity of internal components that are not contaminated. For this purpose, the internal components are encapsulated. This ensures that once the endoscope <NUM> has been successfully dismantled and the encapsulation has been removed, the internal components that are to be reused cannot contaminate other components during reassembly, or in case of failure of the device and exposure of those components during surgery.

As shown in <FIG>, the major active components of the head <NUM> including the integrated camera module <NUM> and the internal features of the light guide <NUM>, such as the prism <NUM>, are encapsulated to form a hermetic seal around those internal components. Specifically, the camera module <NUM> is encapsulated by a shroud <NUM> and as noted above, the light guide <NUM> is integrated with, or solidly encapsulated into, the component that also defines the pulley groove <NUM> and the spigot <NUM>.

The shroud <NUM> interfaces with the light guide <NUM> at a planar joint <NUM> to assemble the head <NUM> as a single capsule. A seal between the light guide <NUM> and the shroud <NUM> is formed by over-moulding or optionally by bonding, welding or compression. The components within the light guide <NUM> and the shroud <NUM> are likewise over-moulded or optionally glued, welded or otherwise encapsulated using a compression fit.

A groove <NUM> surrounding the head <NUM> in alignment with the joint <NUM> creates a line of weakness at which the capsule can be broken to separate the light guide <NUM> and the shroud <NUM> in a controlled manner to remove the protected components inside. More generally, the groove <NUM> exemplifies a disassembly interface at which the camera module <NUM> is preferentially separable from other parts of the head <NUM> such as the light guide <NUM> and/or the light emitter <NUM>. The groove <NUM> is external to the head <NUM> in this example but optionally, a line or point of weakness could be defined within the head <NUM>. Optionally, the groove <NUM> can be shaped to provide a hinge for controlled opening of the capsule, for example if the groove <NUM> does not extend around the entire circumference of the head <NUM>.

<FIG> also shows an optional strip or band <NUM> of a harder material embedded within the head <NUM> under a cutting line, for example located under the groove <NUM> as shown. This allows a laser or knife to cut into the head <NUM> while protecting the internal components of the head <NUM> during the cutting process. For example, a laser could cut into a plastic capsule of the head <NUM> to open or weaken it, while being prevented from penetrating to the inside of the capsule by a metal band <NUM> located under the cut site.

Advantageously, the capsule of the head <NUM> may be opened by applying a bending or twisting force to its outer surface to tear, crack or break the capsule. Optionally, this action may be directed to a predetermined line or point of weakness as described above and/or may follow the application of a cut or scribe mark to the capsule as a preliminary step. Ideally, the required forces are applied to the outer surface of the capsule in a controlled and repeatable manner, for example by using a robotic arm.

Confirming that the capsule of the head <NUM> maintained its integrity during use is important to determine whether or not a component within that capsule can be used again. During disassembly, this check can be done visually, optionally by applying strain or colour dies or scanning frequencies to visualise cracks or to check resonance. Alternatively, or additionally, liquid or gas pressure could be applied to the outer surface of the capsule. If the capsule has failed, a void or pocket in the pressurised capsule would fill with fluid. This can be detected by visual monitoring or by monitoring pressure.

<FIG> exemplifies how the invention may be applied in a circular economy system. In this respect, it is important to protect the integrity of key components after use and to return them. Robust reverse logistics and supply chain management and focused product design and disassembly/reassembly processes are therefore required.

<FIG> shows an endoscope of the invention being removed from a sterile reusable tray (<NUM>), connected to a monitor (<NUM>) and used in ear surgery (<NUM>). After use, the endoscope is placed back in the original tray (<NUM>), although the tray in which the endoscope is supplied or returned could instead be single-use.

An example of a reusable tray <NUM> is shown in <FIG>. In step (<NUM>) of <FIG>, a user pulls a protective backing from a return seal <NUM> and then reseals the tray <NUM> around an endoscope <NUM>, conveniently using the original covering film to close the open top of the tray <NUM>. Advantageously, the user may firstly fill the tray <NUM> with water, thus activating a water-soluble detergent capsule <NUM> in the tray <NUM>. The detergent initiates the cleaning process, loosening overt biological matter and debris from the endoscope <NUM>.

Returning to <FIG>, the tray <NUM> is then placed in a depository provided to individual hospitals (<NUM>). Depositories may provide geolocation and inventory data. When the depository is full, or nearly so, an alert is generated (<NUM>), leading to the depository being transported (<NUM>) to a specialised disassembly unit (<NUM>). This removes the burden of cleaning and waste management from hospitals and eliminates the risk of poor sterilisation.

A global product identification system allows individual serialisation and secure tracking of products and components and validation of the authenticity of those items as part of the returns process. This enables robust implementation of a smart Kanban (lean scheduling) system in which local distributors can be used to transport the endoscope to the disassembly unit.

Advantageously, disassembly units may be robotic cells of a size that makes shipping easy. A set number of such cells could fit into a standard shipping container, or a cell could be implemented in a shipping container. Such cells may be placed regionally or nationally as a key part of a reverse logistics system.

Thus, used endoscopes delivered directly from the hospitals, classified as medical waste, may be fed into robotic cells that serve as disassembly units. Initial disassembly of endoscopes is automated with a pick-and-place robot to protect staff. Robotic arms unpack and dismantle the endoscopes (<NUM>) and sort the parts into: parts for recycling (<NUM>); parts for reuse in the circular economy system (<NUM>); waste for incineration and biodegradable materials.

The parts for reuse in the circular economy system are no longer classified as medical waste and can be shipped internationally (<NUM>) to a circular production facility at which endoscopes are remanufactured (<NUM>). This solution avoids the many regulatory challenges that would have to be overcome if parts were shipped internationally while still classified as medical waste.

Each endoscope undergoes rigorous testing to ensure that it meets standards of safety and sterility equivalent to those of the original endoscope and is packaged ready for resale (<NUM>).

<FIG> shows the robotic cell <NUM> of a disassembly unit, as may be used in step (<NUM>) of <FIG>. In this example, air is drawn from the cell <NUM> through ports <NUM> to apply a partial vacuum to the endoscope <NUM> during its disassembly by robotic arms <NUM>. This is to discourage transfer of particles such as prions from the outer surface of the endoscope <NUM> to its internal protected components. The vacuum could be localised or transient or the entire disassembly process could take place in a low-pressure environment. Alternatively, laminar or other air flow may be applied to the endoscope <NUM> within the robotic cell <NUM> for the same purpose.

Moving on to <FIG>, these drawings show variants of camera modules <NUM> that each have at least two lens elements <NUM>, at least one of which is mounted on and movable by micro electro-mechanical system (MEMS) actuators <NUM>. This enables the lens elements <NUM> to be moved independently of each other or in an accordion fashion. Optionally, the illustrated arrangements of MEMS actuators <NUM> could be replicated on all lens elements <NUM>. MEMS actuators <NUM> could also act on a lens aperture <NUM> of the camera module <NUM> in a similar fashion.

A lens train <NUM> of three longitudinally-spaced lens elements <NUM> is shown in <FIG>. Longitudinally-acting peripherally-positioned MEMS actuators <NUM> act on each lens element <NUM> to vary the longitudinal spacing between the lens elements <NUM>. The effect of this is apparent from a comparison of <FIG> with <FIG>; the former drawing shows the lens train <NUM> expanded longitudinally whereas the latter drawing shows the lens train <NUM> contracted longitudinally. In this example, the lens elements <NUM> move relative to each other in accordion fashion and therefore the longitudinal positions of the lens elements <NUM> are inter-dependent.

<FIG> also show that at least one lens element <NUM> can have further MEMS actuators 84R acting radially to keep that lens element <NUM>, or more generally the lens train <NUM>, in alignment. In principle, similar MEMS actuators 84R could also act on the lens aperture <NUM>.

In <FIG>, the lens elements <NUM> remain parallel and mutually aligned on a common longitudinal optical axis <NUM> as they move longitudinally. Conversely, the variant shown in <FIG> illustrates how MEMS actuators <NUM> on opposite sides of a lens element <NUM> could be controlled independently, for example by extending the MEMS actuators <NUM> on one side and retracting the MEMS actuators <NUM> on the other side. This causes at least one lens element <NUM> to tilt relative to the optical axis <NUM> and to at least one other lens element <NUM>. Similarly, extending the MEMS actuators 84R on one side and retracting the MEMS actuators 84R on the other side will cause at least one lens element <NUM> to move transversely relative to the optical axis <NUM> and to at least one other lens element <NUM>.

These pivoting and translational movements could be used to manoeuvre or manipulate a lens train <NUM> containing complex asymmetric lenses, allowing refocusing in a way that is not possible with simple lenses. For example, a lateral shift of a lens element <NUM> could bring a different optical shape onto the optical axis, thus refocusing the optical system.

In the variant shown in <FIG>, the lens train <NUM> comprises two lens elements <NUM>. The lens elements <NUM> are suspended independently via MEMS actuators <NUM> and therefore are movable relative to a surrounding barrel structure independently of each other. The lens aperture <NUM> could also be mounted in a similar way. Again, provisions may be made for pivoting and/or translational movements like those described above.

Turning next to <FIG> and <FIG>, these drawings show an orienting or drive mechanism <NUM> for turning the head <NUM>, and hence the camera module <NUM> and the light emitter <NUM>, relative to the probe <NUM> of the endoscope <NUM>. The drive mechanism <NUM> is located near the distal end of the probe <NUM> and employs sliding fingers or pawls that could, for example, be powered using MEMS actuators.

Specifically, the drive mechanism <NUM> has a ratchet and pawl arrangement that comprises a ratchet wheel <NUM> coupled to the head <NUM>, for example coaxially for direct drive or via the drive cable <NUM> of preceding embodiments. The drive mechanism <NUM> further comprises a pair of opposed pawls <NUM> that are movable as part of a chain or sequence of movements to engage with and apply torque to the ratchet wheel <NUM>, thereby to drive and control angular stepwise movement of the ratchet wheel <NUM>.

For this purpose, each pawl <NUM> is movable by a respective actuating rod <NUM> and linkage <NUM> to engage and disengage the ratchet wheel <NUM> and to apply torque to the ratchet wheel <NUM> when so engaged. A connecting arm <NUM> extending from each linkage <NUM> is driven by movement of that linkage <NUM> to act on the linkage <NUM> of the opposed pawl <NUM>. In this way, extending one pawl <NUM> to advance the ratchet wheel <NUM> in a particular angular direction releases the other pawl <NUM> from the ratchet wheel <NUM> to free the rachet wheel <NUM> for that movement.

<FIG> shows the complete drive mechanism <NUM> required to turn the ratchet wheel <NUM> in opposite angular directions. For ease of understanding, however, <FIG> omit one of the actuating rods <NUM>, linkages <NUM> and arms <NUM> to illustrate unidirectional angular movement of the ratchet wheel <NUM>. It will nevertheless be clear how these features omitted from <FIG> but shown in <FIG> can be used to turn the ratchet wheel <NUM> in the opposite direction.

The sequence of operation shown in <FIG> is as follows. Firstly, in the rest position shown in <FIG> and corresponding to <FIG>, both pawls <NUM> are engaged with the ratchet wheel <NUM> to prevent angular movement of the head <NUM> relative to the probe <NUM>.

<FIG> shows the actuating rod <NUM> of one of the pawls <NUM> driven longitudinally toward the ratchet wheel <NUM> along a tangential axis that is offset laterally from the centre of the ratchet wheel <NUM>. Initially, this movement pivots the linkage <NUM> relative to the actuating rod <NUM> and the pawl <NUM>. That pivotal movement of the linkage <NUM> moves the arm <NUM> attached to that linkage <NUM> toward and against the opposed pawl <NUM>. This movement of the arm <NUM> disengages the opposed pawl <NUM> from the ratchet wheel <NUM> to free the ratchet wheel <NUM> for movement.

Clockwise movement of the ratchet wheel <NUM> is then driven by further longitudinal movement of the pawl <NUM> that is coupled to the actuating rod <NUM> via the linkage <NUM>, as shown in <FIG>.

Next, the actuating rod <NUM> reaches the end of its longitudinal stroke and starts to return in the opposite longitudinal direction as shown in <FIG>. Initially, this return movement pivots the linkage <NUM> in the opposite direction, pulling the arm <NUM> away from the opposed pawl <NUM>. This allows the opposed pawl <NUM> to reengage the ratchet wheel <NUM>, hence preventing angular movement of the ratchet wheel <NUM>. <FIG> then shows the actuating rod <NUM> retracting further, hence disengaging the pawl <NUM> coupled to the linkage <NUM> from the ratchet wheel <NUM>. Further retraction of the actuating rod <NUM> pulls that pawl <NUM> anticlockwise, sliding across at least one tooth of the ratchet wheel <NUM> to reengage the ratchet wheel <NUM> at a relatively anticlockwise position as shown in <FIG>.

The actuating rod <NUM> is now ready to repeat its longitudinal stroke if the ratchet wheel <NUM> is to be turned further in the clockwise direction. Alternatively, the actuating rod <NUM> can remain stationary if the ratchet wheel <NUM> is to be held at a fixed angular position or is to be driven in an anticlockwise direction by corresponding operation of the actuating rod <NUM>, linkage <NUM> and arm <NUM> associated with the opposed pawl <NUM> as shown in <FIG>.

<FIG> shows another example in which like numerals are again used for like features. In this example, the head <NUM> is not cantilevered from the probe <NUM> but is instead supported to turn about an axis of rotation <NUM> by, and between, a pair of laterally-spaced parallel arms <NUM> that extend distally from the probe <NUM>. Again, the head <NUM> contains and encapsulates a camera module <NUM> and supports at least one light emitter <NUM> that is positioned to illuminate the field of view of the camera module <NUM>. In this example, there are at least two light emitters <NUM>, one each side of the camera module <NUM>.

Optionally, as shown in this example, light is introduced into the head <NUM> from parallel longitudinal light paths <NUM> extending along the probe <NUM>. The light is redirected from those light paths <NUM> toward the head <NUM> by mirrors, light pipes or prisms <NUM> in the respective arms <NUM>, aligned with the axis of rotation <NUM> in mutual opposition about the head <NUM>. Thus, light enters the head <NUM> from opposite sides along the axis of rotation <NUM>. From there, light guides <NUM> such as optical fibres within the head <NUM> convey the light to respective light emitters <NUM>.

In this example, the camera module <NUM> could be electrically powered by conventional means such as sliding contacts or electromagnetic induction. However, it will be apparent that the camera module <NUM> shown in <FIG> could instead be powered by a photovoltaic arrangement using a portion of the light entering the head <NUM>, for example using one or more light guides interposed between the camera module <NUM> and at least one of the arms <NUM> like the embodiment of <FIG>.

Again, features may be provided to facilitate robotic disassembly of the head <NUM> in a circular economy system, such as lines of weakness at which the head <NUM> can be cut or broken apart to access recyclable or reusable components encapsulated within.

Moving on to <FIG>, 14a and 14b, these drawings show examples useful for understanding the present disclosure in the form of endoscopes that resemble a traditional Hopkins® scope.

In the endoscope <NUM> of <FIG>, a tubular capsule <NUM> has its ends closed with lenses or transparent end caps <NUM> to encapsulate a rod lens assembly <NUM>. The rod lens assembly <NUM> comprises a longitudinal array of rod lenses <NUM> within a tubular housing <NUM>, which may for example be of stainless steel. The metallic housing <NUM> of the rod lens assembly <NUM> lends stiffness to the longitudinal shaft of the endoscope <NUM>, noting that the capsule <NUM> is a single-use component that may be moulded of polymer.

A lateral extension of the capsule <NUM> also houses and supports, but does not encapsulate, optical fibres <NUM> that extend parallel to the rod lens assembly <NUM>. The optical fibres <NUM> terminate at the distal end of the endoscope <NUM> in a light emitter <NUM> that is adjacent to the distal end cap <NUM> of the capsule <NUM>. The distal end cap <NUM> serves as a distal lens of the endoscope <NUM>.

The capsule <NUM> is encircled near its proximal end by a groove <NUM> defining a line of weakness for controlled disassembly, whereby the proximal end cap <NUM> can be removed or hinged away from the capsule <NUM>. This allows the rod lens assembly <NUM> to be removed from the capsule <NUM> and reused. For example, the distal end cap <NUM> could be pressed proximally into the capsule <NUM> to push the rod lens assembly <NUM> proximally out of the capsule <NUM>. That telescopic action could also break off or otherwise open the proximal end cap <NUM> if the proximal end cap <NUM> has not already been removed or opened. Preferably, the end caps <NUM> are spaced longitudinally from the rod lens assembly <NUM> to ensure that the rod lens assembly <NUM> is not damaged during removal from the capsule <NUM>.

The capsule <NUM> is supported by a structural support <NUM> that surrounds and shrouds the proximal end of the capsule <NUM>. The groove <NUM> is located within the support <NUM>, which therefore protects the proximal end of the capsule <NUM> that is weakened by the groove <NUM>. The capsule <NUM> must therefore be removed from the support <NUM> when access to the rod lens assembly <NUM> is required. The capsule <NUM> is then held so as to apply even force across the rod lens assembly <NUM> before a force is applied on the proximal side of the groove <NUM> to tear the capsule <NUM>.

The support <NUM> also holds a proximal lens <NUM> in alignment with the rod lens assembly <NUM> and defines a connector <NUM> for coupling a light source to the optical fibres <NUM>. The support <NUM> is preferably made from a biomaterial. Optionally, the optical fibres and the proximal lens could also be encapsulated in a similar manner to the rod lens assembly <NUM>.

The endoscopes <NUM> shown in <FIG> also resemble a traditional Hopkins® scope, with optical fibre light guide illumination, but in this case they each have an integrated, encapsulated camera module <NUM> at a distal end to provide a chip-on-tip solution.

Preferably, as shown, the camera module <NUM> includes a variable-focus lens that is controllable from the proximal end of the endoscope <NUM>. For example, an objective lens <NUM> in front of the image sensor of the camera module <NUM> would allow focusing of the camera module <NUM> by varying the distance between them.

A separate encapsulated control module <NUM> near the proximal end of each endoscope <NUM> controls focus of the camera module <NUM> and receives image data from the camera module <NUM>. In <FIG>, the control module <NUM> receives data from an antenna <NUM> positioned close to the camera module <NUM> to receive that data wirelessly from the camera module <NUM>. Conversely, the control module <NUM> has a wired data connection to the camera module <NUM> in <FIG>.

Focus of the camera module <NUM> may conveniently be controlled by a proximal knob <NUM> that acts on the control module <NUM>. In these examples, the knob <NUM> interacts with the control module <NUM> without physical contact between them. For this purpose, the knob <NUM> has reference markers <NUM> whereby a sensor <NUM> of the control module <NUM> can monitor the movement of the knob <NUM>.

In the endoscope examples useful for understanding the present disclosure in <FIG>, a tubular shaft or probe <NUM> serves as a structural element and as a light guide. Light is conveyed along the probe <NUM> by internal reflection, as shown, to emerge from the distal tip of the probe <NUM> around the camera module <NUM>. In the embodiment of <FIG>, some of that light may power the camera module <NUM> via a photovoltaic cell. In the embodiment of <FIG>, the camera module <NUM> may be powered directly by a wired connection to the control module <NUM>.

Power and data connections to the control module are made via cables <NUM> that couple to connectors <NUM> of the endoscopes <NUM> in <FIG>. In <FIG>, the cable <NUM> also includes fibre optics <NUM> to feed light from a remote light source, not shown, into the light guide of the probe <NUM> via the connector <NUM>. Conversely, in <FIG>, the cable <NUM> provides electrical power to an onboard light source within the endoscope <NUM>, exemplified here by an LED <NUM> that feeds light into light guide of the probe <NUM>.

Turning finally to <FIG>, the endoscope <NUM> of this example useful for understanding the present disclosure has a flexible tubular probe <NUM> that encloses optical fibres <NUM>, a wireless communication module <NUM>, and a steering wire <NUM> that is configured to bend the flexible probe <NUM> along its length. The probe <NUM> also accommodates a working channel that terminates in an exit opening <NUM> in a head component <NUM> at the distal tip of the probe <NUM>.

In addition to defining the exit opening <NUM> for the working channel of the probe <NUM>, the head component <NUM> encapsulates a camera module <NUM>, directs illumination from the optical fibres <NUM> and provides a protective anchor for a plug <NUM> at the distal end of the steering wire <NUM>. Some of the optical fibres <NUM> are directed to illuminate a photovoltaic cell that provides electrical power to the camera module <NUM>. In conjunction with the probe <NUM> and a handle structure <NUM>, the head component <NUM> also maintains protection of internal components of the endoscope <NUM> against ingress of contaminants.

The handle <NUM> includes a control element <NUM> to manoeuvre the steering wire <NUM> without direct physical interaction between the control element <NUM> and an internal mechanism <NUM> that is encapsulated within the handle <NUM>. For this purpose, a sensor <NUM> of the mechanism <NUM> monitors movement of a reference marker <NUM> on the control element <NUM>, causing the mechanism <NUM> to respond to such movement by pushing or pulling the steering wire <NUM> to the desired extent. Optionally, the mechanism <NUM> is assisted or powered by a motor. Points of weakness <NUM> may be provided for controlled disassembly of the handle <NUM> to extract the encapsulated mechanism <NUM> for reuse.

Many other variations are possible within the scope of the present invention which is defined by the appended claims.

For example, data communication and power transmission between parts of a surgical instrument could, in principle, be achieved by wireless techniques other than by employing light travelling through transparent outer sections between capsules, modules or components. Examples include techniques employing radio frequency (RF) or magnetic resonance communication. However, electrical contacts on, or conductors between, the outer surfaces of adjoining capsules, modules or components could potentially be used for this purpose.

Data communication and power transmission in an instrument may be effected by daisy-chaining between successive capsules, modules or encapsulated components of the instrument. Thus, each capsule, module or component in the daisy-chain arrangement has a means of receiving data or power from an external source and/or a means of transmitting or conveying data or power to an external receiver. Such daisy-chain features are exemplified in this specification by the provisions for receiving light into the head to power the camera module and by the provisions for transmitting data from the camera module to an external receiver. In the case of RF communication, daisy-chaining is advantageous because the short transmission distance means that power can be kept low, making it easier to provide sufficient electrical energy and ensuring that RF radiation does not penetrate deep into the patient's body.

Claim 1:
A medical scope (<NUM>) comprising:
an elongate body (<NUM>);
an imaging head (<NUM>) supported by and rotatably movable relative to a mount of the body about an axis of rotation (<NUM>) extending from the mount, the imaging head including
a light emitter (<NUM>) for illuminating a field of view of the imaging head; and
a light path extending from the body parallel to the axis of rotation and through the imaging head to the light emitter, the light path including a light inlet of the imaging head opposed to a light outlet of the body.