Patent Application
20190216574
The present invention relates to a marking apparatus for marking the location of tissue imaged through an imaging device, as well as to a system for imaging and marking tissue. The marking apparatus is particularly useful for marking the location or delineating the margin of a clinical feature of interest present on or under the surface of a patient's skin. Another aspect of the invention also provides an adjustable spacer for such a system.
Basal cell carcinoma (BCC) accounts for around 75% of all skin cancers. A recent study shows that BCC is the most common malignant disease in the UK, with the number of cases having risen by 80% in a decade. Most BCCs and other skin cancers are treated by surgical removal of the cancerous region.
The current method for surgical removal of malignant or cancerous regions involves identifying a ‘cancer margin’, the region within which the skin cancer (basal or squamous cell carcinomas) is present. The ‘surgical margin’, the region to be removed, is subsequently established. The surgeon marks the ‘surgical margin’ directly on the surface of the skin using a handheld felt tip marker pen. These pens are normally sterile and individually packaged and use a surgical grade ink, typically some formulation of gentian violet. The sterilised felt tip marker pen is used to mark the surface of the skin so as to delineate the identified ‘surgical margin’. Desired skin flaps, needed to repair the wound, are often also marked using the marker pen.
Marking is typically guided by visual clinical examination. The ‘surgical margin’, marked for surgical removal of the skin cancer, requires the surgeon to judge the ‘cancer margin’ by eye. The ‘surgical margin’ includes the cancer present on the surface of the skin visible to the eye with an added safety margin of skin (often between 3-10 mm) around the visible ‘cancer margin’. The safety margin is selected to ensure surgical removal of any invisible infiltration of the disease. Sometimes, however, the disease will have infiltrated to underlying layers of tissue, beyond the safety margin.
A problem with surgical removal of skin cancers is determining the amount of tissue to cut out around the cancer. Using a hand-held marker pen and marking the ‘surgical margin’ by eye has several drawbacks. The lack of imaging means that if the cancer has extended laterally under the surface of the skin, these extensions will not be seen. As a consequence, the ‘surgical margin’ will not contain all of the cancer and surgical removal will be incomplete, causing the cancer to return. This often requires a costly secondary operation, further treatment and delay of effective treatment. If too much is cut out, the treatment is unnecessarily aggressive, leading to complications which may require continuing expensive treatment. Furthermore, healthy tissue is removed, leaving a larger wound than necessary that may look unsightly.
Non-invasive imaging technologies can assist the naked eye in identifying the size of the cancerous tissue by showing to the surgeon the otherwise invisible lateral extensions of the cancer underneath the surface of the skin. Imaging technologies can also help by providing a better view of the lesion on the skin surface by magnification and the reduction of surface glare (as in dermoscopy). Examples of non-invasive imaging technologies currently used in assisting the naked eye in defining the cancer margin include optical coherence tomography (OCT), dermoscopy, reflectance confocal microscopy and ultrasound imaging.
However, imaging technologies are not used routinely as an aid in surgical margin marking due to the difficulty in marking the skin or tissue in practice. In order to image tissue sections of interest, the imaging probe must be in contact with the surface of the skin. Once the imaging probe is lifted off the skin or moved to the side, which is necessary to leave room to make a mark with a pen, the image is lost and the surgeon must estimate from memory the precise location of the tissue that was imaged. The advantages of new optical imagining technologies in accurately tracking the lateral extension of cancers are lost.
Examples of prior art skin markers used with image guidance can be found in US-2007/0225605, US-2014/0005542, US-2006/0106312 and U.S. Pat. No. 6,745,067.
The present disclosure provides an improved marking apparatus for marking the location of imaged tissue sections, an improved system for imaging and marking, as well as a configurable spacer for such a system.
According to an aspect of the present disclosure, there is provided marking apparatus for marking tissue imaged through an imaging device, including: a viewing element including an imaging window providing an imaging zone through which tissue can be imaged; a marker implement; a coupling device to which the marker implement is connected; the coupling device being configurable to position the marker implement in a first position substantially out of the imaging window and a second position in the imaging zone of the imaging window; the marker implement being able to apply a mark when in the second position and thereby to mark the tissue in the imaging zone while the apparatus remains in position on the tissue.
The apparatus and system disclosed herein provides a mechanism by which it is possible to apply a mark on the surface of imaged tissue (such as skin) while keeping the imaging device in position on the tissue, thereby enabling the mark to be applied under image-guidance. This is not possible with the prior art systems referred to above. The physician can apply a mark accurately, without the need to have to estimate from memory the precise location of the tissue being imaged.
Advantageously, the apparatus includes a guide member to which the marker implement is coupled, the guide member being structured to move the marker implement in a direction substantially orthogonal to the imaging window.
By enabling the marker implement to approach the tissue to be marked at a right angle to the tissue can ensure the accurate placement of a mark at the location of the tissue being imaged, in other words precisely in the position which the physician identifies on screen. It is not excluded, however, that the marker implement may be moved in a non-orthogonal direction, while in other embodiments it may not move at all from the second position, for instance in cases where the implement is able to spray or otherwise apply an ink mark from a distance. In some embodiments, the marker implement may be arranged to move in a diametrical direction, for instance at an acute angle to the skin. This can be achieved by appropriate design of the moving mechanism.
In some preferred embodiments, the guide member is operable to move the marker implement so as to extend through the imaging window to apply a mark to tissue. In other words, the marker implement can be extended beyond the window to press upon tissue held against the imaging window.
In some embodiments, the guide member includes a first guide channel section substantially orthogonal to the imaging window. The guide member can include a second guide channel section substantially parallel to the imaging window, the second guide channel section providing for movement of the marker implement in a direction substantially parallel to the imaging window from the first to the second positions.
In some preferred embodiments, the marker implement is removable, from the marking apparatus, for example so as to enable the marker implement to be changed or to be disposed.
Providing a marking apparatus where the marker implement is removable enables easy replacement of the marker implement to prevent cross-contamination between uses.
In some preferred embodiments, the marking apparatus is integral with an imaging device, particularly built-in to the casing of the imaging device. At least the viewing element and imaging window are preferably integral with a casing of the imaging device.
In some embodiments, the marking apparatus can be removable from the imaging device, enabling periodic maintenance and cleaning of the whole system and of the imaging device.
In some embodiments, the marking apparatus can include a support structure attachable to a casing of an imaging device.
The support structure can be used in some embodiments to support the pin guides which assist in positioning the marking apparatus on tissue. The support structure can also act as a housing, to protect the components of the apparatus.
In some preferred embodiments, the viewing element is in the form of a spacer element, the spacer element including a front face which incorporates the imaging window. Advantageously, the spacer element can include front and rear faces, and can include a length adjusting mechanism which can adjust a distance between the front and rear faces; wherein a change in said distance effects a change in focal position of the imaging device.
The ability to vary focal length can enable adjustment for different imaging devices but more importantly the ability to focus into the depth of skin tissue so as to locate diseased tissue underneath the skin surface.
In some preferred embodiments, the length adjusting mechanism can adjust the distance between the front and rear faces from 0 mm to substantially 20 mm.
In some preferred embodiments, the length adjusting mechanism can adjust the distance between the front and rear faces from substantially 5 mm to substantially 11 mm.
In some preferred embodiments, the spacer element is integral with the marking apparatus. This advantageously provides a ready fitted device requiring no set-up prior to use of the device.
The apparatus can advantageously include a triggering or actuating mechanism (herein after referred to as triggering mechanism) connected to the coupling device for moving the marker implement between the first and second positions. In some preferred embodiments, the triggering mechanism is operable to move the marker implement to extend through the imaging window.
According to another aspect of the disclosure, there is provided a system for imaging tissue and marking imaged tissue, including: an imaging device; marking apparatus coupled to the imaging device; and a display system coupled to the imaging device and through which images obtained from the imaging device can be displayed; wherein the marking apparatus includes: a viewing element including an imaging window providing an imaging zone through which tissue can be imaged; a marker implement; a coupling device to which the marker implement is connected; the coupling device being configurable to position the marker implement in a first position substantially out of the imaging window and a second position in the imaging zone of the imaging window; the marker implement being able to apply a mark when in the second position and thereby to tissue in the imaging zone while the apparatus remains in position on the tissue.
In at least some embodiments with the system, as a physician moves the imaging device over different tissue sections, an image of the tissue section is displayed on the display system. As a feature of interest appears on the display system, the physician can activate the triggering mechanism, causing the marking apparatus to place a mark on the tissue section being imaged.
Advantageously, the system can include a feedback device operable to generate a feedback signal once a mark has been applied by the marking implement.
In at least some embodiments, the imaging device is most suitable for use with an OCT imaging device.
According to another aspect of the present disclosure, there is provided a configurable viewing element for an imaging device, the viewing element can include a spacer element provided with a front face and a rear face, an imaging window being disposed in the front face and providing an imaging zone through which tissue can be imaged, and a length adjustment mechanism coupled to the spacer element and operable to adjust a distance between the front and rear faces so as in use effects a change in focal position of an imaging device.
In some preferred embodiments, the length adjustment mechanism is operable to adjust the distance between the front and rear faces from substantially 5 mm to substantially 11 mm.
In some embodiments, he viewing element advantageously includes a housing member having a viewing passage passing therethrough from the rear to the front faces.
In some preferred embodiments, the imaging window is an opening in the viewing element.
The apparatus and system disclosed herein can be used to mark the location of imaged tissue sections. A mark is applied without needing to lift off or move the marking apparatus to the side in order to make room to apply the mark. The mark can therefore accurately indicate the location of any identified features of interest. The marking apparatus described herein can be used to delineate a cancer margin, including any cancer extensions infiltrated to underlying tissue sections, not visible to the naked eye. An appropriate surgical margin can then be marked for removal.
Other features and advantages of the system and apparatus disclosed herein will become apparent from the specific description which follows.
Embodiments of the present invention are described below, by way of example only, with reference to the accompanying drawings.
Described below are various embodiments of a marking apparatus for marking the location of imaged tissue. The embodiments described below are examples only, the specific form of the components described herein not being essential to the teachings herein. The imaging device is not described in detail herein as the teachings herein are applicable to known imaging devices.
The embodiments described below and shown in
Referring first to
The embodiment of marking apparatus 10 shown is designed to fit and attach to imaging device 12 and specifically at head end 18 of probe housing 14. The marking apparatus includes support structure 20 with two side panels 22 and 24 which lie alongside respective sides of probe housing 14. The two side panels 22 and 24 are connected together by front panel 26. The two side panels 22 and 24 are in this embodiment made of plastics material and preferably as a single piece. They are preferably smooth and flat or gently curved, so that they can easily be wiped clean, as well as being shaped to fit the contour of probe housing 14, leaving sufficient space for housing and preferably supporting the internal components of the marking assembly.
Two additional housing members 21 and 23, which in this embodiment are in the form of flat panels, are attached to respective side panels 22 and 24.
A drive mechanism or moving mechanism 36 is also provided at side panel 22. As illustrated in this embodiment, moving mechanism 36 can be, for example a toothed wheel fitting within a partially toothed slot (not visible in
In the embodiment illustrated in
Spacer 38 can be of plastics material or another suitable material that can be cleaned or sterilised.
Marking apparatus 10 can also include triggering mechanism 48, which in this embodiment is a trigger button, positioned at the front of apparatus 10 and is of a type which can be actuated by a user's finger.
Marking apparatus 10 can also include marker implement 58, which can be a type of marker suitable for applying a mark to tissue. In some preferred embodiments, implement 58 is a felt tip marker pen with a nib. In the view of
Two thumbwheels 36 can be seen located on opposing sides of apparatus 10, by respective side panels 22 and 24. Two thumbwheels makes the apparatus suitable for left or right handed use. Two housings members 21 and 23 can also be seen located on opposing sides of apparatus 10, by respective side panels 22 and 24.
Referring to
Marker implement 58 is fitted to coupling device 64 which can include guide followers, typically follower pins, which are located in the guide channels and are able to slide therein. In
Side panel 22 includes guide features 33 and 35 which in this embodiment are in the form of rectangular slots. Inserts 30 and 31 slide through slots 33 and 35, so as to position support structure 20 in a retracted position and an extended position, as will be described in further detail below. Some embodiments may include additional guide features 37. The marker implement 58 can be seen in the first position and outside imaging window 50.
In use, imaging device 12 is positioned on a patient's skin or tissue at a point of interest, for example where there is suspected malignant growth or other feature which it is desired to image. In this disclosure references may be made to skin only but it is to be understood that the disclosure is equally applicable to tissues and, as a result, any references to skin is to be understood as applying to tissues, and vice versa, where appropriate. In practice, spacer 38 is placed against the skin surface, thereby locating the probe head. In the first instance, triggering mechanism 48 is left untouched, such that marker implement 58 is outside imaging window 50. In some preferred embodiments imaging zone 52 will not be obstructed by guide member 64. Although in some embodiments, a part of the guide member may be in or part of imaging zone 52.
Imaging device 10 can be connected to a processing unit and display such that images obtained from the probe head can be displayed substantially in real time. The physician can move probe head 10 around the skin or tissue in order to determine the perimeter of the skin zone of interest. When the physician identifies, in this embodiment in the centre of imaging zone 52, a perimeter position of interest, the physician can press the triggering mechanism 48, causing marker implement 58 to move from the first, inactive position, through to the second position at the end of the second guide channel section 62. Marker implement 58 moves from the first position to the second position while the apparatus remain in position on the tissue and while imaging window 50 remains in position on the tissue. Marker implement 58 then moves orthogonally along first guide channel section 60 so as to apply a mark at that position. Probe 12 is not moved out of place during this operation and imaging window 50 remains in position on the surface of the skin, such that a mark can be placed precisely at the position of interest. For this purpose, the system can display positioning means, such as crosshairs on the displayed image within imaging zone 52. The crosshairs are indicative of the location within imaging zone 52 where marker implement 58 will apply the mark on the surface of the tissue. This allows the physician to see and target, under image guidance, exactly where in the field of view of the displayed image the mark is being applied. The physician can also move imaging window 50 under image guidance so as to position the crosshairs at the exact location of the clinical feature of interest and apply the mark where the physician intends. Preferably, the crosshairs are displayed in the centre of the displayed image, indicative of the centre point of imaging window 50. A number of other types of positioning means are suitable, including a circular centering point, a centering dot and/or a bullseye.
In other words, a mark can be applied precisely with no, or at least little, parallax error and without having to lift off or move the probe head from its imaging position. In some preferred embodiments, marker implement 58 uses a gentian violet medical grade ink, suitable for surgical marking of skin. However, other suitable medical grade inks can be used.
First guide channel section 60 ensures, or at least increase the likelihood, that marker implement 58 moves orthogonally in the last part of its movement, and therefore along a line normal of the plane of imaging window 50. As a result, a mark can be placed precisely at the centre point even when the skin surface is not completely flat against the front face 42 of spacer 38.
Marker implement 58 is preferably resilient or resiliently held such that pressure applied by marker implement 58 on the skin surface is controlled. In some embodiments, coupling device 64, particularly the part connected to marker implement 58, is resiliently deformable, while in other embodiments marker implement 58 can be held in place be a resiliently deformable coupling device 64 such as a spring or spring-like element (not shown). In other embodiments, marker implement 58 itself can be deformable under pressure, although this is not preferred.
Once a mark has been applied, triggering mechanism 48 can be released, whereupon marker implement 58 is moved back to its inactive position, by resiliency in the assembly. The probe head can be moved again and once another position of interest is identified triggering mechanism 48 is pressed again. In this manner, a plurality of points can be marked on the patient's skin so as to delimit an area for treatment.
The function and operation of spacer 38 is now described with reference to
Thumbwheels 82 can be rotated in the opposite direction to move the components of marking apparatus 10 back and to shorten the spacing between spacer 38 and housing 14.
In practice, the spacer element can be adjustable in length by between 0 millimetres and around 20 millimetres.
For imaging skin cancers such as basal cell carcinoma, spacer element 38 is preferably adjustable in length by around 6 millimetres, in practice by moving the front face 42 of spacer 38 between 5 millimetres from the front face of the probe head to 11 millimetres therefrom. This range of length is particularly suitable when using an OCT imaging device. However, spacer 38 can be adjustable in length by other distances suitable for other imaging technologies. Depending on the imaging probe being used the lengths of the spacer element will need to be adjusted. For some imaging technologies, it is preferable that the spacer remains in the back position as in
It will be appreciated that for imaging other features or symptoms a different depth range may be provided.
In some embodiments, the left and right thumbwheels 82 are connected together by a spindle (not shown) which can pass through bore 90 in internal tubular support 92 of the two housing halves of probe housing 14. Tubular supports 92 can in practice abut one another, providing rigidity and strength to probe housing 14.
As explained briefly above, imaging device 12 and apparatus 10 are typically part of an imaging system which includes an imaging processing unit and a display. Such systems are generally known, although without probe 96 and assembly taught herein. Thus, in some embodiments, the disclosed devices and methods can comprise these other elements of an imaging system.
In most embodiments viewing window 50 can simply be an aperture, although it is not excluded that this can be closed by a transparent or translucent panel for example of glass or plastics material. Such a panel can be simply light transmissive although in some embodiments the panel can be at least partially concave or convex to provide a focusing function.
In some preferred embodiments, spacer 38 is integral with the remainder of apparatus 10.
In some embodiments, spacer 38 is a separable component.
In some embodiments, apparatus 10 can be incorporated into probe housing 14, in which case the focal distance of the probe can be changed by adjusting the position of the probe relative to probe housing 14.
In some preferred embodiments, marker implement 58 is a felt-tip nib. In other embodiments, marker implement 58 can be another suitable device, such as inkjet device. It can also be solenoid or hydraulically operated for at least a part of its range of movement.
Marking apparatus 10 can be used also with an ultrasound imaging device, for instance for locating and marking the location and length of a vein.
In some embodiments, marking apparatus 10 can be used with applications where needles need inserting at an accurately predetermined position above a feature of clinical significance, such as when taking a biopsy of the skin or during plastic surgery or during spinal anaesthesia procedures. Device 10 can be used for locating benign lesions or during aesthetic procedures. Apparatus 10 can also be used in dermoscopy and reflectance confocal microscopy, with an opto-acoustic, a reflectance confocal microscopy, a terahertz, a raman spectroscopy imaging device and/or a combination of OCT and reflectance confocal microscopy imaging device, as well as in any other medical procedures for which imaging and marking of an imaged body part is appropriate. Spacer 38 can be adaptable depending upon the imaging technology being used, in particular whether spacer 38 is movable between a back position and an extended position and the distance the front face 42 of spacer 38 can be moved from the front face of the probe head.
The features described above can be implemented in a variety of ways. Another embodiment of marking an apparatus is described below. It is to be understood that features of the above embodiments can be used with the embodiment described below and vice-versa. The following embodiment, shown in
A coupling device or link 264 has one end connected to marker implement 258 and the other end connected to trigger 248. Coupling link 264 connects to trigger 248 via connecting pin 262 (not shown). Coupling link 264 pivots about pin 262.
Marking implement 248 is in the first position outside imaging window 250 and retracted from the front face 242 of the spacer. In this first position or the non-use position, marker implement 258 sits within housing 240 of spacer 238.
Marking apparatus 200 is used in a similar way to marking apparatus 100. Spacer 238 is placed against the skin surface and probe head 218 is moved around the skin in order to determine a skin zone of interest. A user or physician can press push button 217 to capture a screenshot of the image viewed by the probe. The screenshot is obtained without the physician having to move or lift the imaging window off the skin surface and while the apparatus remains in position on the tissue. The screenshot can therefore be accurately captured at the exact location of any identified features of interest. As a perimeter position of interest is identified, the physician can press trigger 248, causing simultaneous movement of marker implement 258 into the extended (in-use) position, as well as of spacer 238 into the extended position. Movement of trigger 248 from the inactive position to the active position causes drive link 272 to pivot forwardly, turning gear 273 in an anti-clockwise direction and gear 274 in a clockwise direction and moving push link 280 forward. The forward movement of push link 280 moves spacer 238 forwardly from marker body 214. The forward movement of spacer 238 causes the front face 242 to push the surface of the skin away from probe 212 and results in a change in spacing between probe head 218 and face 244 and thus of probe head 218 and front face 242 with imaging window 250. This can be necessary for certain types of imaging techniques, including for example reflectance confocal microscopy (RCM), Optical coherence tomography (OCT) and/or combinations of OCT and RCM imaging techniques amongst others.
In at least some embodiments, movement of trigger 248 into the active position at the same time causes drive arm 282 to pivot about pin 291, driving pin 298 forwardly and upwardly in slot 292. This causes pin 300 to move forwardly and upwardly in slot 294, moving coupling link 264 and moving maker implement 258 into imaging zone 252 and extending it beyond imaging window 250 so as to apply a mark to the surface of the skin. Marker implement 258 moves from the first position to the extended position while marking apparatus 200 remains in position on the tissue and while imaging window 250 remains in position on the tissue at the location of the identified feature of interest. Marker implement 258 can therefore apply a mark to the surface of the skin, marking the point of interest, without having to move probe head 218 or imaging window 250 and without having to lift imaging window 250 off the surface of the skin thereby accurately indicating the location of the identified feature of interest. Marker implement 258 can therefore apply the mark to the skin while probe 212 and marking apparatus 200 remain aligned as the physician had intended and with imaging window 250 aligned and remaining in contact with the tissue surface. This allows the physician to apply the mark under image-guidance. This also allows the physician to image the feature of interest at the same time as the mark is being applied.
As with previous embodiments, once a mark has been applied, trigger 248 can be released, whereupon marker implement 258 is moved back to its first non-use position by resiliency in the assembly. As marker implement 258 returns to the non-use position, spacer 238 moves back to its original retracted position.
As with previous embodiments, the system can display positioning means, such as crosshairs on the displayed image within imaging zone 252. The crosshairs are indicative of the location within imaging zone 252 where marker implement 258 will apply the mark on the surface of the tissue. This allows the physician to see and target, under image guidance, exactly where in the field of view of the displayed image the mark is being applied. The physician can also move imaging window 250 under image guidance so as to position the crosshairs at the exact location of the clinical feature of interest and apply the mark where the physician intends.
All optional and preferred features and modifications of the described embodiments and dependent claims are usable in all aspects of the invention taught herein. Furthermore, the individual features of the dependent claims, as well as all optional and preferred features and modifications of the described embodiments are combinable and interchangeable with one another.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1616153.1 | Sep 2016 | GB | national |
This application is a continuation of International Application No. PCT/GB2017/052848 having an international filing date of Sep. 22, 2017 entitled “System for Marking the Surface of a Patient's Tissue in the Course of Imaging”. The '848 international application claimed priority benefits, in turn, from United Kingdom Patent Application No. 1616153.1 filed on Sep. 22, 2016. The '848 international application and the '153.1 UK application are hereby incorporated by reference herein in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/GB2017/052848 | Sep 2017 | US |
| Child | 16362099 | US |
