Cooling system of imaging head of fluorescence imaging equipment

Abstract

An imaging head (139) of a fluorescence imaging device (100) is presented. An imaging head (139) includes a dissipater (221) coupled to a container (215, 234) at an operative side (218) of the container by a corresponding seal (236 o) to define a chamber (230). A lighting unit (206) is disposed outside the chamber (230) on the dissipater (221). An acquisition unit (209) is arranged in the chamber (230); the acquisition unit (209) is coupled to the dissipater (221) at its opening (227) via a corresponding seal (236i). A fluorescence imaging device (100) is also presented, comprising the imaging head (139). The invention further relates to a corresponding imaging method and a medical method.

Description

Technical Field

[0001] The present disclosure relates to the field of medical devices, and more particularly, to fluorescence imaging devices. Background Art

[0002] The following describes the background of the present disclosure and discusses technologies related to its context. However, even when this discussion involves documents, actions, artifacts, etc., it does not imply or represent that the technology discussed is part of the prior art or common general knowledge in the field related to the present disclosure.

[0003] Imaging devices are commonly used in a variety of medical applications to provide a visual representation of a patient's body part, even if the body part is not directly visible. In particular, fluorescence-type imaging devices exploit the phenomenon of fluorescence that occurs in fluorescent substances (called fluorophores), which fluoresce when illuminated. The fluorescence emitted from different locations in the body part can then be used to construct a fluorescence image that represents the fluorophores present in the body part. For example, a fluorescent agent (which may be adapted to target a specific molecule at a desired target, such as a lesion such as a tumor, and then remain fixed during a fluorescence molecular imaging (FMI) procedure) can be administered to a patient. The representation of the (fixed) fluorescent agent in the corresponding fluorescence image helps to identify (and quantify) the corresponding target. This information can be used in a variety of medical applications, for example, in surgery to identify the margins of a lesion to be removed.

[0004] To this end, the imaging device is provided with an imaging head for selecting the body part to be imaged. The imaging head comprises: an illumination unit for providing (fluorescence) excitation light for exciting fluorophores present in the body part; and an acquisition unit for acquiring a fluorescence image thereof.

[0005] Imaging heads (particularly their illumination units) generate significant amounts of waste heat as a byproduct of their operation. However, excessive heating of the imaging head can adversely affect its performance. In particular, excessive heating of the illumination unit can cause the characteristics of the excitation light (e.g., radiant power and wavelength) to drift, which in turn produces corresponding noise in the fluorescence image. Therefore, a cooling system is typically provided to cool the imaging head, in order to maintain a stable (relatively) low temperature, particularly the temperature of its illumination unit (ensuring consistent illumination).

[0006] However, cooling of imaging heads is very challenging, especially when used during surgical procedures.

[0007] In particular, operating rooms have special ventilation requirements to prevent the opening surgical cavity in a body part from being infected, usually requiring laminar air in its area. Therefore, it is difficult to use forced air cooling systems, in which (cooler) air is forced to flow towards the imaging head to replace (warmer) air, through which waste heat is transferred by convection to the imaging head; in fact, the position of the imaging head close to the body part hinders the maintenance of the laminar flow of air at its surgical cavity.

[0008] Furthermore, it is necessary to prevent any non-sterile material from coming into contact with the surgical cavity. Therefore, the risk of infection of the patient can be caused by a liquid cooling system, in which waste heat is transferred to a (liquid) coolant circulating through the imaging head; in fact, any leak of the cooling system can cause the coolant, which is usually non-sterile, to fall onto the surgical cavity. More generally, depending on its toxicity, the leakage of the cooling liquid can pose a safety risk to the patient.

[0009] In any case, the size and structure of the cooling system should interfere as little as possible with the handling of the imaging head for the body part to be imaged.

[0010] KR-A-101436543 discloses a fluorescent imaging system having an LED light source and a camera mounted at its through hole. A cooling device is provided at the rear end of the LED light source. A controller supplies cooling water to the cooling device through two circulation pipes connected thereto. However, this cooling device is not effective in cooling the camera; moreover, it does not provide any protection against possible leakage of the cooling water. SUMMARY

[0011] The present invention is set out in the appended claims.

[0012] The present disclosure is summarized herein to provide a basic understanding of the disclosure; however, the sole purpose of this summary is to introduce some concepts of the disclosure in a simplified form as a prelude to the more detailed description that follows it, and it should not be interpreted as identifying key elements of the disclosure, nor should it be interpreted as delimiting its scope.

[0013] Generally, the present disclosure is based on the idea of creating a chamber sealed by a dissipator.

[0014] In particular, one aspect provides an imaging head of a fluorescent imaging device. The imaging head comprises a dissipator coupled with a container located at an operating side of the dissipator by a corresponding seal to define a chamber. An illumination unit is arranged on the dissipator outside the chamber. An acquisition unit is arranged inside the chamber; the acquisition unit is coupled with the dissipator at its opening by a corresponding seal.

[0015] Another aspect provides a fluorescent imaging device comprising the imaging head.

[0016] Another aspect provides a method for imaging a body part of a patient using the imaging head.

[0017] Another aspect provides a corresponding medical method.

[0018] More specifically, one or more aspects of the present disclosure are set out in the independent claims, and advantageous features thereof are set out in the dependent claims, wherein the wording of all claims herein is incorporated herein in its entirety by reference (with any advantageous features described for a particular aspect applying equally to all other aspects mutatis mutandis). BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The scheme of the present disclosure, as well as further features and advantages thereof, will be best understood with reference to the following detailed description, which is given purely in a non-limiting manner and is to be read in conjunction with the accompanying drawings (wherein, for simplicity, corresponding elements are represented by equal or similar reference numerals and their explanation is not repeated, and the name of each entity is generally used to indicate its type and attributes, such as value, content and representation). In this regard, it is clear that the drawings are not necessarily drawn to scale (certain details may be exaggerated and / or simplified) and, unless otherwise indicated, are only used to conceptually illustrate the structures and processes described herein. In addition, references to directions and relative positions (e.g., front, back, up, down, lateral, etc.) should be understood with respect to the usage of the corresponding entities. In particular:

[0020] Figure 1 shows a diagrammatic representation of a fluorescence imaging apparatus in which schemes according to embodiments of the present disclosure may be implemented,

[0021] Figure 2 A schematic cross-sectional view of an imaging head of a fluorescence imaging device according to an embodiment of the present disclosure is shown, and

[0022] Figures 3-4 Exploded views of an imaging head according to an embodiment of the present disclosure from different viewing directions are shown. DETAILED DESCRIPTION

[0023] See especially Figure 1 , shows a graphical schematic diagram of a fluorescence imaging device 100 in which a scheme according to an embodiment of the present disclosure can be implemented.

[0024] (Fluorescence) imaging device 100 is used in medical applications to examine a patient's body part (not shown) during an imaging procedure (e.g., in diagnosis, treatment, and / or surgery) by applying fluorescence imaging techniques. For example, imaging device 100 is used to assist surgeons in fluorescence-guided surgery (FGS), particularly fluorescence-guided resection (FGR) of tumors.

[0025] The imaging apparatus 1000 includes the following components.

[0026] The cart 103 houses a (power) supply unit 106 and a control unit 109 for respectively powering and controlling the imaging device 100. Four casters 112 (only three visible in the figure) are arranged at corresponding lower corners of the cart 103 to facilitate movement of the imaging device 100 (with foot brakes, not shown, provided for securing the imaging device 100 in place). A column 115 extends upward from the back surface of the cart 103. The column 115 has a handle 118 for its operator to move the imaging device 100. An arm 121 extends from the column 115 above the cart 103. A main monitor 124 (for displaying images to the operator) and a keyboard 127 with a pointing device, such as a mouse or trackball (for the operator to input information / commands) are mounted on the arm 121. A pivot arm 130 is mounted on the top of the column 115 (above the arm 121). An auxiliary monitor 133 (for displaying images to a physician, such as a surgeon) is mounted on pivoting arm 130 (to allow it to be rotated in any direction). Also mounted on top of column 115 (next to pivoting arm 130) is an articulating arm 136. An imaging head 139 (for selecting the body part to be imaged) is suspended from articulating arm 136.

[0027] For example, articulated arm 136 includes two links formed by corresponding rods 142 and 145. Rod 142 is coupled at its ends to column 115 via two revolute joints 148 and 151, which allow the rod to rotate relative to the revolute joints about a vertical axis and a horizontal axis, respectively. Rod 145 is coupled at its ends to the other end of rod 142 via a revolute joint 154, which allows the rod to rotate relative to the revolute joint about a horizontal axis. The support for imaging head 139, formed by fork 157, is coupled to the other end of rod 145 at a common point between its tines via a revolute joint 160, which allows the support to rotate relative to the revolute joint about a vertical axis. Imaging head 139 is coupled at its center to the tines of fork 157 via corresponding revolute joints 163i and 163o, which allow the imaging head to rotate relative to the revolute joint about a horizontal axis (representing the pitch axis of imaging head 139). Thus, imaging head 139 has five degrees of freedom, as it can translate in space (forward-backward, left-right, and up-down) via (revolute) joints 148-154, it can rotate about its vertical axis via (revolute) joint 160, and it can rotate about its pitch axis via (revolute) joints 163i, 163o. Imaging head 139 is provided with two handles 166a and 166b for positioning the imaging head by an operator.

[0028] A heat exchanger, such as chiller 169, is further housed within cart 103. Inlet and outlet pipes 172i, 172o (only partially visible in the figure), circulate a cooling fluid (or coolant) between chiller 169 and imaging head 139. A coolant is a substance with a relatively high heat capacity that accumulates and transfers heat; preferably, the coolant is in a liquid state (e.g., water). Specifically, inlet pipe 172i supplies, i.e., pumps, (cooler) coolant to imaging head 139 for cooling (as described below), thereby heating the coolant. Outlet pipe 172o returns the (relatively hot) coolant to chiller 169, which removes heat from it (dissipating it to the external environment). To this end, the (inlet / outlet) ducts 172i, 172o are insulated (to limit heat dissipation) and flexible (to follow the movement of the imaging head 139); for example, the ducts 172i, 172o extend within the cart 130 between the cooler 169 and the column 115, extend within the column 115, pass between the column 115 and the articulated arm 136 outside the joints 148-151, extend within the rod 142, pass between the rod 142 and the rod 145 outside the joint 154, extend within the rod 145, pass between the rod 145 and the fork 157 outside the joint 160, and pass between the fork 157 and the imaging head 139 through the joints 163i, 163o. In this way, the cooler 169 can be kept relatively far away from the patient during the imaging procedure and benefit the patient's safety; for example, in surgery, this allows avoiding (or at least greatly reducing) the cooler 169's adverse effects on the special ventilation requirements of the corresponding operating room (necessary to prevent infection of the surgical cavity being opened in the body part), such as maintaining laminar air flow within its area.

[0029] Now refer to Figure 2 , a schematic diagram illustrating a cross-sectional view of an imaging head 139 (of a fluorescence imaging apparatus) according to an embodiment of the present disclosure.

[0030] The imaging head 139 is configured to image a scene contained within its field of view 203 (defined by the portion of the world within the three-dimensional solid angle to which the imaging head 139 is sensitive). In particular, in the context of a surgical procedure, the scene (not shown) is associated with a patient to whom a fluorescent agent has been previously administered (e.g., including fluorophores adapted to accumulate in corresponding targets (e.g., tumors)); the scene includes a body part of the patient in which a surgical cavity has been opened (e.g., a small skin incision in minimally invasive surgery) to expose a lesion (e.g., a tumor) to be removed.

[0031] The imaging head 139 includes the following components.

[0032] The illumination unit 206, the acquisition unit 209, and the service component 212 define the functional components of the imaging head 139 (implementing its functions). Specifically, the illumination unit 206 is used to illuminate the scene in the field of view 203. The illumination unit 206 generates (fluorescence) excitation light, which has a wavelength and energy suitable for exciting the fluorophores of a fluorophore (e.g., of the near-infrared (NIR) type), and possibly white light, which appears essentially colorless to the human eye (e.g., encompasses all wavelengths of the spectrum visible to the human eye at a comparable intensity). The acquisition unit 209 is used to acquire a (digital) image of the scene in the field of view 203. The acquisition unit 209 acquires a fluorescence image, which is defined by the fluorescence emitted by the fluorophores of the fluorophore when illuminated by the excitation light (which then represents the corresponding target within the body part). Indeed, upon absorbing the excitation light, the fluorophores enter an excited (electronic) state; this excited state is unstable, causing the fluorophores to quickly decay to a ground (electronic) state, thereby emitting fluorescence light whose intensity depends primarily on the amount of fluorophore illuminated. In addition, the acquisition unit 209 can also acquire a reflectance (or photographic) image defined by visible light reflected from the contents of the field of view 203 illuminated by white light (thus representing the contents of the field of view 203 visible to the human eye). Specifically, the acquisition unit 209 includes optics 209c for collecting light from the field of view 203, as well as other components for generating a fluorescence / reflectance image from the collected light (e.g., a dichroic mirror to separate the collected light into fluorescence light and visible light; filters to remove any residual fluorescence / visible light components; a fluorescence camera to generate a fluorescence image from the fluorescence light; a reflectance camera to generate a reflectance image from the visible light, etc.). The collection optics 209c are arranged at the center of the illumination unit 206 (to ensure optimal operation of the imaging head 139). The service components 212 include one or more (active / passive) components that support the operation of the illumination unit 206 and the acquisition unit 209 (e.g., electronic components such as voltage regulators, power switches, fuses, etc.). A container 215 (e.g., a container of plastic material) has an operating side 218 for exposing the illumination unit 206 and the acquisition unit 209. In the specific embodiment shown in the figures, the container 215 is in the form of a bell (e.g., having a generally cylindrical shape), wherein its operating side 218 is defined by a (lower) mouth (i.e., a cavity for accessing the container 215). The acquisition unit 209 and the service component 212 are arranged within the container 215. The illumination unit 206 is arranged at the operating side 218 of the container 215 (in this case, the mouth of the bell), with the collection optics 209c extending therethrough. The imaging head 139 has a cooling system for cooling it, in particular the illumination unit 206, the acquisition unit 209, and the service component 212 of the imaging head.

[0033] In the solution according to the embodiments of the present disclosure, for this purpose a dissipator 221 is provided in the form of a (dissipating) plate. The dissipator 221 is made of a thermally conductive material (such as aluminum) for transferring heat (as described below), which has a ring shape matching the container 215 and the collection optics 209c (in the embodiment in question, circular). In particular, the dissipator 221 has a size corresponding to the container 215 at the operating side 218 of the container (in this case, the mouth of the bell), with its outer edge 224o matching it. The (through) hole 227 (in the embodiment in question, having a circular shape) corresponding to the collection optics 209c defines an opening at the center of the dissipator 221, with its inner edge 224i matching it. The dissipator 221 is coupled with the container 215 at the operating side 218 of the container (in this case, the mouth of the bell) to define a chamber 230. The illumination unit 206 is arranged on the dissipator 221, outside the chamber 230 (below it in the figure). The acquisition unit 209 and the service components 212 are arranged inside the chamber 230, with the collection optics 209c operating through the hole 227. Also arranged inside the chamber 230 are an inlet duct 233i and an outlet duct 233o for circulating a coolant for the dissipator 221. In particular, the inlet duct 233i extends from the inlet duct 172i to the dissipator 221 to supply it with a (cooler) coolant from a cooler (not shown in the figure) for cooling the dissipator, thus warming up the coolant; the outlet duct 233o extends from the dissipator 221 to the outlet duct 172o to return the (warmed-up) coolant to the cooler, from which it takes away heat. An outer seal 236o acts between the outer edge 224o of the dissipator 221 and the container 215 at the operating side 218 of the container (in this case, the mouth of the bell); likewise, an inner seal 236i acts between the inner edge 224i of the dissipator (at its hole 227) and the collection optics 209c. The (inner / outer) seals 236o, 236i facilitate the coupling of the dissipator 221 with the container 215 and the collection optics 209c to prevent the coolant from escaping from the container 215 in the event of a leak in the cooling system in the portion corresponding to the (inlet / outlet) ducts 233i, 233o, for example, along the ducts 233i, 233o and / or at the connections of said ducts with the ducts 172i, 172o and with the dissipator 221. During the imaging process, the illumination unit 206 and the collection optics 209c (and then the dissipator 221) are generally vertically or obliquely facing downwards. Thus, in this way, at least the lower part of the imaging head 139 (in the operating condition) is sealed so as to keep the coolant inside the chamber 230 even in the event of a leak in the cooling system.

[0034] The above structure is very effective in cooling imaging head 139. In particular, the heat generated by illumination unit 206 is transferred to dissipator 221 by conduction, where it is absorbed by the coolant circulating in the dissipator. Furthermore, the coolant circulating in chamber 230 (via dissipator 221 and pipes 233i, 233o) cools the air enclosed therein by convection and radiation. This (cooled) air then absorbs the heat generated by acquisition unit 209 and service component 212.

[0035] All of the above allows maintaining a stable (relatively) low temperature throughout the imaging head 139 and has a beneficial effect on its operation (in particular, on the illumination unit 206 providing consistent illumination of the field of view 203, on the acquisition unit 209 providing noise reduction in the fluorescence image, and on the service component 212 providing correct functioning thereof).

[0036] The sealing of the chamber 230 ensures that the coolant cannot escape therefrom even in the event of a leak in the cooling system (ducts 233i, 233o and / or corresponding connections), at least in the normal orientation of the imaging head 139 during the imaging process (typically, with the illumination unit 206 and the collection optics 209c facing downwards). This prevents the coolant from falling onto the body part being imaged, thereby avoiding any risk to the patient's health (even if the coolant is toxic), especially the risk of infection during surgery, where the coolant (typically non-sterile) may enter the surgical cavity.

[0037] The desired result is achieved in a relatively simple manner. In fact, the dissipator 221 cooperates with the structure of the imaging head 139 (in particular with the arrangement of the illumination unit 206 and the collecting optics 209 c); moreover, the sealing of the chamber 230 is obtained by making use of the container 215 already available in the imaging head 139.

[0038] As a further refinement, the imaging head 139 includes one or more (additional) dissipators 239. In particular, in the specific embodiment of the figures, only a single dissipator 239 is shown coupled to the acquisition unit 209 (e.g., in the form of a sleeve surrounding it). The dissipator 239 is again made of a thermally conductive material (e.g., aluminum) for transferring heat. The dissipator 239 is coupled to an inlet duct 233i and an outlet duct 233o for circulating coolant through it, wherein the inlet duct 233i extends from the inlet duct 172i to the dissipator 239 to supply (cooler) coolant from the cooler for cooling it, and the outlet duct 233o extends from the dissipator 239 to the outlet duct 172o to return (warmed) coolant to the cooler (directly or indirectly). In particular, in the example shown in the drawings, the inlet duct 233i extends from the inlet duct 172i to the dissipator 239 and then from the dissipator 239 to the dissipator 221, while the outlet duct 233o extends from the dissipator 221 to the dissipator 239 and then from the dissipator 239 to the outlet duct 172o.

[0039] Now refer to Figures 3-4 , which shows an exploded view of the imaging head 139a in different viewing directions according to an embodiment of the present disclosure.

[0040] from Figure 3 Initially (shown in its normal orientation during the imaging process, with the illumination unit 206 and collection optics 209c facing downward), the outer seal 236o and inner seal 236i are implemented as corresponding gaskets (e.g., O-rings) that fit into grooves at the outer edge 224o and inner edge 224i, respectively, of the dissipator 221. The (outer / inner) gaskets 236o, 236i are made of a deformable material (e.g., an elastomer); when the imaging head 139 is assembled, the outer gasket 236o and inner gasket 236i are compressed between the dissipator 221 and the container 215 (as shown in the partially cutaway view in the accompanying drawings) and between the dissipator 221 and the collection optics 209c, respectively, to seal their interfaces. This structure is very simple, yet effective; moreover, it allows the imaging head 139 to be opened and closed (e.g., for maintenance operations) in a relatively simple manner.

[0041] One or more sensors 303a, 303b are disposed within chamber 230. Sensors 303a, 303b are electrically connected to the imaging device's control unit via corresponding cables (not shown). These cables extend from sensors 303a, 303b through the imaging device's joints 163i, 163i, articulated arms, supports, and carts (not shown) to the control unit. Sensors 303a, 303b detect the presence of any liquid, particularly coolant, within chamber 230. To this end, each sensor 303a, 303b generates a presence signal when coolant reaches it (due to a cooling system leak). The control unit receives any presence signals from sensors 303a, 303b (e.g., by polling them). In response, the control unit enters an alarm state. Specifically, the control unit stops a cooler (not shown) from supplying coolant to imaging head 139, e.g., via a corresponding relay. This prevents further coolant from being supplied to imaging head 139, thereby limiting the leak. Furthermore, the control unit switches off the power supply to imaging head 139, for example, via a corresponding power switch; this prevents a short circuit that could be caused by the coolant. Simultaneously, the control unit warns the operator accordingly, for example, by outputting a corresponding message on one or more monitors of the imaging device (not shown). This significantly reduces the risk of damage to imaging head 139 in the event of a cooling system leak; furthermore, it allows the operator to quickly intervene to ensure a safe environment (e.g., by removing imaging head 139 from the patient).

[0042] Preferably, sensors 303a and 303b are multiple and arranged at different locations within chamber 230 to detect the presence of coolant in corresponding orientations of imaging head 139. Specifically, in the example discussed, the imaging head can translate (with three degrees of freedom), rotate about a vertical axis, and swivel about its (horizontal) pitch axis, which passes through joints 163i and 163o (as shown in the figure, indicated by corresponding arrows); furthermore, imaging head 139 is typically used with downward-facing illumination unit 206 and collection optics 209c. Therefore, in this case, two sensors 303a and 303b are sufficient to detect coolant leaks in any orientation of imaging head 139. Specifically, sensors 303a and 303b are positioned on dissipator 221 at opposite ends thereof and extend in a (sensing) direction perpendicular to the pitch axis. In the event of a leak, coolant would settle onto dissipator 221 by gravity. When imaging head 139 is vertically extended, both sensors 303a and 303b detect coolant. When imaging head 139 rotates clockwise (in the same direction as the arrow), coolant accumulates on the right side of dissipator 221 in the figure, allowing it to be detected by sensor 303a. When imaging head 139 rotates counterclockwise (in the opposite direction of the arrow), coolant accumulates on the left side of dissipator 22 in the figure, allowing it to be detected by sensor 303b. This allows any coolant leak to be quickly detected in its early stages (regardless of the orientation of imaging head 139).

[0043] A coolant circulation loop 306 (e.g., consisting of a series of interconnected conduits connected in series, such as four straight pipes in the example shown) is provided on the dissipator 221. The circulation loop 306 extends from an inlet connector 309i (to which the inlet pipe 233i is connected) to an outlet connector 309o (to which the outlet pipe 233o is connected) on the inner surface of the dissipator 221 within the chamber 230 (e.g., mounted thereon (e.g., screwed thereon). This provides good cooling of the dissipator 221 while promoting cooling of the air in the chamber 230 (and subsequently the acquisition unit 209 and the service component 212).

[0044] The ducts 233i, 233o are made of a material with high thermal conductivity (e.g., aluminum) and extend along at least a portion of the imaging head 139. For example, the ducts 233i and 233o are connected between connectors 309i, 309o at the dissipator 221 (the lower end of the imaging head 139) and further connectors 312i and 312o, respectively, located at joints 163i and 163o (the center of the imaging head 139). This further promotes cooling of the air in the chamber 230, and subsequently in the acquisition unit 209 and the service component 212.

[0045] Dissipator 221 has another, smaller (through) hole 315 defining a corresponding opening, which is provided with a grommet 318 for passing (electrical) cables 321 (or more). Grommet 318 is made of a deformable material (e.g., an elastomer); it is press-fit into hole 315 (to seal the interface therebetween) and has a (through) hole through hole 315 that is smaller in width than the cross-section of cable 321. Thus, cable 321 is inserted into grommet 318 under pressure, causing grommet 318 to be compressed, thereby sealing the interface therebetween. Cable 321 electrically connects lighting unit 206 to a control unit (for power / control); to this end, cable 321 extends from the control unit through the cart, column, articulated arm, joints 163i, 163o, and grommet 318. This allows electrical connection of the illumination unit 206 within the imaging head 139 while keeping it (at least partially) sealed, thereby preventing coolant from escaping from the imaging head 139 even in the event of a leak in the cooling system.

[0046] The container 215 of the imaging head 139 includes, in addition to the bell-shaped member denoted by reference numeral 215b, a cover 215c denoted by reference numeral 218m mounted on the bell-shaped member 215b at the mouth of the container. The cover 215c protects the lighting unit 206 while exposing its functional components (described below).

[0047] Move to Figure 4(in the bottom view, the imaging head 139 is shown), the illumination unit 206 comprises a printed circuit board (PCB), or simply board 405 (formed by a base of electrically insulating material with one or more tracks of electrically conductive material). The board 405 matches (in the example discussed also with a similar annular shape) the dissipator 221; in particular, the board 405 has a (through) hole 410 corresponding to the hole 227, which defines an opening in its center. In the board 405 a (through) hole 415 is formed, which defines an opening for the cable 321, said hole being located in the same radial position of the hole guard ring 318 in the dissipator 221. The board 405 is fastened (for example, mounted, such as screwed) on the outer surface of the dissipator 221 outside the chamber 230 (only partially visible in the figures), coaxial thereto (the hole 410 surrounds the hole 227) and rotated so that the hole 415 is substantially coaxial with the hole guard ring 318. A plurality of (excitation) light sources 420 (for example, based on LEDs) of excitation light are provided, mounted on the front surface 405f (opposite the dissipator 221) of the board 405; for example, the light sources 420 are arranged uniformly in a plurality of radial extensions of alignment (for example, 8 in the example shown in the figures, each with 4 light sources) mounted on corresponding tracks of the board 405. A plurality of (white light) light sources 425 (for example, also based on LEDs) of white light are also provided, mounted on the front surface 405f of the board 405; for example, the light sources 425 are interposed between the alignments of light sources 420. The cable 321 from the hole guard ring 318 of the dissipator 221 extends through the hole 415 to the front surface 405f of the board 405. The cable 321 comprises a plurality of conductors (not shown in the figures) connected to corresponding tracks of the board 405 (in turn connected to the light sources 420, 425).

[0048] The cover 215c is provided with a window 430 defining an opening matching (in its center) the hole 227, a plurality of windows 435 defining corresponding openings matching the light sources 420, and a plurality of windows 440 defining corresponding openings matching the light sources 425 (around the window 430). The cover 215c is mounted on the bell 215b (only partially visible in the figures) so that the window 430 is coaxial with the hole 227 (and the hole 410), rotated so that the windows 435 and 440 are substantially coaxial with the light sources 420 and 425, respectively. In this way, the cover 215c covers the board 405 (in particular, its tracks) so as to protect it. At the same time, the windows 435 and 440 expose the light sources 420 and 425, respectively, so that they illuminate the field of view of the imaging head 139; in addition, the window 430 exposes the collection optics 209c (through the hole 227 and the hole 410) so that it acquires the fluorescence and reflection images of the field of view 139 of the imaging head.

[0049] During operation, the imaging head 139 may also be enclosed in a sterile drape (not shown). A sterile drape is a single-use (disposable) cover made of a sterile, flexible, and transparent material; for example, a new sterile drape is used during each surgery to further reduce the risk of infection for the corresponding patient. The sterile drape can also be used to wrap the imaging head 139 to provide additional protection against any leakage of coolant.

[0050] Revise

[0051] To meet local and specific requirements, those skilled in the art may make numerous logical and / or physical modifications and alterations to the present disclosure, provided that they remain within the scope of the claims. More specifically, although the present disclosure has been described with a certain degree of detail with reference to one or more embodiments thereof, it should be understood that various omissions, substitutions, and variations in form and details, as well as other embodiments, are possible. Specifically, different embodiments of the present disclosure may be practiced even without the specific details (such as numerical values) listed in the preceding description to provide a more thorough understanding thereof; conversely, well-known features have been omitted or simplified to avoid obscuring the description with unnecessary detail. Furthermore, it is expressly intended that specific elements and / or method steps described in connection with any embodiment of the present disclosure may be incorporated into any other embodiment as a matter of general design choice. Furthermore, items presented in the same group and in different embodiments, examples, or alternatives should not be construed as being in fact equivalent to one another (but are independent and autonomous entities). In any case, each numerical value should be modified according to the applicable tolerance; in particular, unless otherwise specified, the terms "substantially," "about," "approximately," etc. should be understood to mean within 10%, preferably 5%, and more preferably 1%. In addition, each numerical range should be explicitly referred to as any possible number on the continuum within the range (including its endpoints). Ordinal numbers or other qualifiers are used only as labels to distinguish elements with the same name, but do not in themselves imply any priority, precedence, or order. The terms include, contain, have, contain, involve, etc. should be taken as open, non-exhaustive meanings (i.e., not limited to the items recited); the terms based on, rely on, according to, depend on, etc. should be taken as non-exclusive relationships (i.e., involving possible further variables); the term "a" should be taken as one or more (unless otherwise expressly stated); the term "means for..." (or any means plus function expression) should refer to any structure adapted or configured to perform the relevant function.

[0052] For example, an embodiment provides an imaging head for a fluorescence imaging device. However, the imaging head can be any fluorescence imaging device (see below).

[0053] In one embodiment, the imaging head is used to image a body part of a patient in a medical imaging application. However, the imaging head can be used to image any body part of any patient in any medical imaging application (see below).

[0054] In one embodiment, the imaging head is configured to image a body part of a patient while suspended above the patient. However, the imaging head can be configured to be suspended above the patient in any manner (e.g., mounted on any suspension structure, handheld, an end effector of a robotic system or a co-manipulator, etc.).

[0055] In one embodiment, the imaging head includes an illumination unit for illuminating the field of view of the imaging head with fluorescence excitation light. However, the illumination unit can be of any type (e.g., having any number and type of light sources, such as LEDs, OLEDs, LECs, lasers, etc., arranged in any manner, such as radially, circumferentially, etc., with or without any type of additional white light source, etc.) and for providing any fluorescence excitation light (e.g., NIR, infrared (IR), visible light, etc.).

[0056] In one embodiment, the imaging head includes an acquisition unit for acquiring fluorescence images of the field of view. However, the acquisition unit can be of any type (e.g., based on any collection optics, EMCCD, CMOS, InGaAs, PMT, etc. sensors, with or without a reflectivity camera, etc.), and can be used to acquire any number and type of fluorescence images (e.g., of any size / resolution, at any frame rate, independently or superimposed on corresponding reflectance images, etc.).

[0057] In one embodiment, the imaging head comprises a container having an operative side for exposing the illumination unit and the acquisition unit. However, the container may be of any type (e.g., any material, shape, size, and structure, such as a bell-shaped piece closed with a lid, a vessel closed with a top, two half shells joined together, etc.).

[0058] In one embodiment, the imaging head includes a dissipator for dissipating heat. However, the dissipator can be of any type (eg, any material, of any thickness, with or without fins, etc.).

[0059] In one embodiment, the dissipator comprises a plate having an opening, an outer edge at the opening, and an inner edge. However, the opening can be of any type (e.g., of any size, shape, located in any position, etc.), and the outer / inner edges can be of any type (e.g., with corresponding grooves, flat, etc.).

[0060] In an embodiment, the dissipator is coupled with the container at the operating side of the container to define a chamber. However, the dissipator can be coupled with the container in any way (e.g., snap-on, screw-on, at any location corresponding to the operating side, e.g., at its border or slightly inside, etc.) to define any chamber (e.g., having any shape, size, fully sealed or only partially sealed, etc.).

[0061] In an embodiment, the lighting unit is arranged on the dissipator outside the chamber. However, the lighting unit can be arranged on the dissipator in any way (e.g., mounted, glued, welded, etc., covering all or only part of it, fully or only partially surrounding its opening, etc.).

[0062] In an embodiment, the acquisition unit is arranged inside the chamber to operate through the opening. However, the acquisition unit can be arranged inside the chamber in any way (e.g., extending along its entire length or only partially, extending further or not laterally, etc.) and it can operate through the opening in any way (e.g., flush with the dissipator, protruding or sinking into the dissipator, etc.).

[0063] In an embodiment, the imaging head comprises an inlet duct and an outlet duct for circulating a cooling liquid of the dissipator. However, the inlet / outlet ducts can be of any type (e.g., having any size, cross-section, flexibility / rigidity, running fully outside the dissipator or at least partially inside the dissipator along any path, etc.) for circulating any coolant fluid (e.g., liquid, such as water, a mixture of water and glycol, etc., gas, etc.).

[0064] In an embodiment, the inlet duct and the outlet duct are both arranged inside the chamber. However, the inlet / outlet ducts can be arranged inside the chamber in any way (e.g., extending in any direction, for any range, etc.).

[0065] In an embodiment, the imaging head comprises an outer seal acting between the outer edge of the dissipator and the container and an inner seal acting between the inner edge of the dissipator and the acquisition unit for preventing the coolant fluid from falling on the patient in case of leakage. However, the outer seal and the inner seal can be of any type (e.g., for making the corresponding interface liquid- or air-tight, each implemented by a gasket, e.g., an O-ring, a sheet gasket, a spiral-wound gasket, etc., an adhesive, a cement, etc.).

[0066] Further embodiments provide additional advantageous features, however, these features can be completely omitted in the basic implementation. In this regard, it is expressly intended that the features of each of the following embodiments can be combined, either individually or in combination with the features of any number of the other following embodiments, with the features described above.

[0067] In one embodiment, the container comprises a bell having a mouth at the operating side. However, the bell can be of any type (e.g., cylindrical, trumpet-shaped, etc.), and it can have any mouth (e.g., round, square, etc., in any position, etc.).

[0068] In one embodiment, the container includes a lid mounted on the bell at the mouth of the bell. However, the lid can be of any type (e.g., flat, round, etc.) and can be mounted on the bell in any manner (e.g., screw-on, snap-on, etc.).

[0069] In one embodiment, the cover has an opening exposing the acquisition unit. However, the opening of the cover may be of any type (eg the same as or different from the opening of the dissipator).

[0070] In one embodiment, the cover has one or more additional openings that expose the lighting unit. However, the additional openings of the cover can be of any number and type (e.g., of any size and shape, the same or different from each other, in any position, etc.).

[0071] In one embodiment, the imaging head includes one or more sensors disposed within the chamber for detecting leaks of the coolant fluid. However, the sensors may be of any number, type (e.g., printed sensors, sensor cables, flow meters, etc.), and located in any location (e.g., at the dissipator, throughout the chamber, along the inlet / outlet piping, etc.).

[0072] In one embodiment, the sensor is disposed on the dissipator. However, this result can be achieved in any manner (eg, mounting the sensor on the dissipator, on a container close to the dissipator, etc.).

[0073] In one embodiment, the sensor is a plurality of sensors arranged at different locations for detecting leaks of the coolant fluid in corresponding orientations of the imaging head. However, any number of sensors may be provided, and the sensors may be arranged at any location for any corresponding orientation of the imaging head (e.g., rotated about any number of horizontal axes, tilt axes, etc.).

[0074] In one embodiment, the sensor comprises two sensors arranged at opposite ends of the dissipator along a sensing direction perpendicular to the longitudinal axis of the imaging head. However, the sensing direction may be of any type (eg, extending sideways, transversely, etc.).

[0075] In an embodiment, the imaging head includes a circulation loop of coolant fluid coupled with the inlet and outlet conduits. However, the circulation loop can be of any type (e.g., extend along any path, such as a straight line, a curved line, etc., formed by a single conforming element or any number of interconnected elements, etc.).

[0076] In an embodiment, the circulation loop is disposed on the dissipator within the chamber. However, the circulation loop can be disposed on the dissipator in any manner (e.g., mounted, glued, welded, etc.).

[0077] In an embodiment, the inlet and outlet conduits are configured to extend along at least a portion of the imaging head for cooling air within the chamber. However, the inlet / outlet conduits can extend along the chamber in any manner (e.g., along their entire length or only partially, in any path, etc.).

[0078] In an embodiment, the imaging head includes one or more additional dissipators for dissipating heat. However, the additional dissipators can be of any number and any type (e.g., of any material, structure, size, etc.).

[0079] In an embodiment, the additional dissipators are coupled with the inlet and outlet conduits for circulating the coolant fluid. However, the dissipators and additional dissipators can be coupled with the inlet / outlet conduits in any manner (e.g., in series and / or in parallel, each dissipator connected with a corresponding connector at the container directly or through one or more other dissipators, connected in any order between them, etc.).

[0080] In an embodiment, at least one additional dissipator is arranged to dissipate heat generated by the acquisition unit. However, the dissipators acting on the acquisition unit can be of any number and combined with any number of other dissipators acting on different components of the imaging head (e.g., sensors, service components, etc.), the number of which other dissipators can be reduced to zero in various cases; moreover, each dissipator acting on the acquisition unit can be of any type (e.g., arranged around, on the side, etc.).

[0081] In an embodiment, the dissipator includes a further opening. However, the further opening can be of any type (e.g., of any size, shape, located in any position, etc.).

[0082] In an embodiment, the further opening is provided with a guard ring. However, the guard ring can be of any type (e.g., of any shape, size, of any material, etc.).

[0083] In one embodiment, the grommet is used to seal the passage of at least one cable connected to the lighting unit. However, the grommet is applicable to any number and type of cables (e.g., cables for providing power, sending control signals, receiving response signals, etc.); in any case, the possibility of electrical contact with the lighting unit outside the chamber is not excluded.

[0084] Embodiments provide a fluorescence imaging device for imaging a body part of a patient in a medical imaging application, the fluorescence imaging device including the above-described imaging head. However, the fluorescence imaging device can be of any type (e.g., a guided surgical device, a scanner, etc.) and used for any medical imaging application (e.g., surgery, diagnosis, treatment, etc.).

[0085] In one embodiment, the fluoroscopic imaging apparatus includes a suspension structure for suspending the imaging head above the patient. However, the suspension structure can be of any type (e.g., any articulated arm, such as mounted on a cart, ceiling, wall, etc., a cantilever, a hook, etc.).

[0086] In one embodiment, the fluorescence imaging apparatus includes a heat exchanger for cooling the coolant fluid. However, the heat exchanger can be of any type (eg, a chiller, a heat pump, a heat exchanger in which the fluids flow in parallel, countercurrent, or cross-flow, etc.).

[0087] In one embodiment, the heat exchanger is separate from the imaging head. However, the heat exchanger can be separated from the imaging head in any manner (eg, arranged in a cart, remote from the imaging head, etc.).

[0088] In one embodiment, the fluorescence imaging apparatus includes an additional inlet conduit (for supplying coolant fluid from the heat exchanger to the inlet conduit) and an additional outlet conduit (for returning the coolant fluid from the outlet conduit to the heat exchanger). However, the additional inlet / outlet conduits can be of any type (e.g., having any size, cross-section, flexibility / rigidity, being freestanding, or extending at least partially within one or more components of the imaging apparatus, such as an articulated arm, a support, a cart, etc. of the imaging apparatus).

[0089] In one embodiment, the fluorescence imaging device comprises a control unit. However, the control unit may be of any type (eg, a microcontroller, a personal computer, etc.).

[0090] In one embodiment, the control unit is coupled to the sensor. However, the control unit may be coupled to the sensor in any manner (eg, a wired connection, a wireless connection, etc. operating in any manner).

[0091] In one embodiment, the control unit is coupled to the sensor for receiving an indication that a coolant fluid leak has been sensed. However, the control unit may receive this information in any manner (e.g., by polling the sensor, listening for notifications from the sensor, etc.).

[0092] In one embodiment, the control unit is configured to enter an alarm state in response to sensing a coolant leak. However, the control unit may enter an alarm state in any manner (e.g., once a sensor detects coolant fluid, after two or more confirmations, if any sensor fails to respond, etc.) to perform any number and type of actions (e.g., stopping the supply of coolant fluid, shutting off power to the imaging head, outputting any visual and / or audible warnings, etc.).

[0093] In one embodiment, the control unit is configured to stop the supply of coolant fluid from the heat exchanger to the inlet pipe in an alarm state. However, the supply of coolant fluid can be stopped in any way (e.g., closing the heat exchanger, closing another inlet pipe, etc.).

[0094] In one embodiment, the control unit is configured to shut down the power supply to the imaging head in the event of an alarm condition. However, the power supply may be shut down in any manner (eg, automatically, requiring manual confirmation, etc.).

[0095] In one embodiment, the suspension structure includes one or more joints for rotating the imaging head about a lateral axis perpendicular to its longitudinal axis (the sensor extends in a sensing direction, the sensing direction being perpendicular to the lateral axis). However, this result can be achieved in any manner (e.g., using one or more revolute joints, ball joints, etc.) for rotating the imaging head about any lateral axis (e.g., pitch, yaw, roller, etc.).

[0096] Generally, similar considerations apply if the imaging head and the fluorescence imaging device each have different structures or contain equivalent components, or have other operational characteristics, provided that they remain within the scope of the claims. In any case, each component can be separated into more elements, or two or more components can be combined into a single element; furthermore, each component can be replicated to support and perform the corresponding operations. Furthermore, unless otherwise specified, any interaction between different components generally need not be continuous and can occur directly or indirectly through one or more intermediate components.

[0097] The embodiments provide a method of imaging a body part of a patient in a medical imaging application. However, the method can be used to image any body part (e.g. one or more organs, regions of organs or tissues, in any pathological / healthy condition, etc.) and any patient (e.g. a human, an animal, etc.) in any medical imaging application (see above). In any case, while the method can be helpful to a physician, it only provides intermediate results that can be helpful to him / her, but the strict medical activity is always performed by the physician himself / herself.

[0098] In an embodiment, the method comprises acquiring one or more fluorescence images of the body part with the imaging head described above. However, the fluorescence images can be any number; moreover, the same considerations described above regarding the characteristics of the imaging head apply to the corresponding steps of the method.

[0099] In an embodiment, the method comprises outputting a representation of the body part based on the fluorescence images. However, the representation of the body part can be of any type (e.g. a fluorescence image, a fluorescence image combined with any reflectance image, etc.) and it can be outputted in any way (e.g. displayed on any device, like a display, virtual reality glasses, etc., or more generally in any way, in real time or offline), like printed, remotely transmitted, etc.

[0100] In general, similar considerations apply if the same solution is implemented with equivalent methods, provided that the solution remains within the scope of the claims (by using similar steps with the same functionality of more steps or parts of steps, removing some non-essential steps or adding further optional steps); moreover, the steps can be executed in a different order, simultaneously or in an alternative way (at least in part).

[0101] The embodiments provide a medical method. In an embodiment, the medical method comprises imaging a body part of a patient with the method described above. In an embodiment, the medical method comprises performing a medical procedure related to the body part, according to the representation of the body part. However, the medical procedure can be of any type (e.g. any surgical procedure in the broadest meaning of the term, like a surgical procedure for therapeutic purposes, for preventive purposes, for aesthetic purposes, etc.; any diagnostic procedure in the broadest meaning of the term, like aimed at finding new pathologies, monitoring known pathologies, etc.; a therapeutic procedure in the broadest meaning of the term, e.g. aimed at curing a pathological condition, avoiding its progression, preventing the occurrence of a pathological condition or just to improve the comfort of the patient, etc.).

Claims

1. An imaging head (139) of a fluorescence imaging device (100), the imaging head being used to image a body part of a patient in a medical imaging application when suspended above the patient, wherein the imaging head (139) comprises: an illumination unit (206) for illuminating the field of view (203) of the imaging head (139) with fluorescent excitation light, an acquisition unit (209) for acquiring a fluorescent image of the field of view (203), a container (215, 215c) having an operating side (218) for exposing the lighting unit (206) and the acquisition unit (209), a dissipator (221) for dissipating heat, comprising a plate having an opening (227), an outer edge (224o) at the opening (227) and an inner edge (224i), wherein the dissipator (221) is coupled to the container (215) at an operating side (218) of the container to define a chamber (230), the lighting unit (206) is arranged on the dissipator (221) outside the chamber (230), and the acquisition unit (209) is arranged in the chamber (230) to operate through the opening (227), an inlet pipe (233i) and an outlet pipe (233o), the inlet pipe and the outlet pipe being used to circulate the coolant fluid of the dissipator (221), the inlet pipe (233i) and the outlet pipe (233o) being arranged in the chamber (230), An outer seal (236o) acting between the outer edge (224o) of the dissipator (221) and the container (215, 215c), and an inner seal (236i) acting between the inner edge (224i) of the dissipator (221) and the acquisition unit (209) are used to prevent the coolant fluid from falling on the patient in the event of leakage.

2. The imaging head (139) according to claim 1, characterized in that The container (215) includes a bell-shaped member (215b) having a mouth (218m) at the operating side and a cover (215c) mounted on the bell-shaped member (215b) at the mouth (218m) of the bell-shaped member, the cover (215c) having an opening (430) exposing the acquisition unit (209) and one or more additional openings (435, 440) exposing the lighting unit (206).

3. The imaging head (139) according to claim 1 or 2, characterized in that The imaging head (139) includes one or more sensors (303a, 303b) disposed within the chamber (230) for detecting leaks of the coolant fluid.

4. The imaging head (139) according to claim 3, characterized in that The sensors (303a, 303b) are arranged at the dissipator (221).

5. The imaging head (139) according to claim 3 or 4, characterized in that The sensors (303a, 303b) are a plurality of sensors (303a, 303b) arranged at different positions for detecting leakage of the coolant fluid at corresponding orientations of the imaging head (139).

6. The imaging head (139) according to claim 5, characterized in that The sensors (303a, 303b) include two sensors (303a, 303b) arranged at opposite ends of the dissipator (221) along a sensing direction perpendicular to a longitudinal axis of the imaging head (139).

7. The imaging head (139) according to any one of claims 1 to 6, wherein The imaging head (139) includes a circulation loop (306) of coolant fluid connected to an inlet pipe (233i) and an outlet pipe (233o), and the circulation loop (306) is arranged on the dissipator (221) and in the chamber (230).

8. The imaging head (139) according to any one of claims 1 to 7, wherein The inlet duct (233i) and the outlet duct (233o) are configured to extend along at least a portion of the imaging head (139) for cooling air within the chamber (230).

9. The imaging head (139) according to any one of claims 1 to 8, wherein The imaging head (139) comprises one or more further dissipators (239) for dissipating heat, the further dissipators being coupled to the inlet duct (233i) and the outlet duct (233o) for circulating coolant fluid, at least one of the further dissipators (239) being arranged to dissipate heat generated by the acquisition unit (209).

10. The imaging head (139) according to any one of claims 1 to 9, wherein The dissipator (221) comprises a further opening (315) provided with a grommet (318) for sealing the passage of at least one cable (321) connected to the lighting unit (206).

11. A fluorescence imaging device (100) for imaging a body part of a patient in a medical imaging application, wherein: The fluorescent imaging device (100) comprises an imaging head (139) according to any one of claims 1 to 10 and a suspension structure (136) for suspending the imaging head (100) above a patient.

12. The fluorescence imaging device (100) according to claim 11, characterized in that The fluorescence imaging apparatus (100) comprises a heat exchanger (169) for cooling coolant fluid exiting from an imaging head (139), a further inlet conduit (172i) for supplying coolant fluid from the heat exchanger (169) to an inlet conduit (233i), and a further outlet conduit (172o) for returning coolant fluid from an outlet conduit (233o) to the heat exchanger (169).

13. The fluorescence imaging device (100) according to claim 11 or 12 when comprising an imaging head (139) according to any one of claims 3 to 10, characterized in that The fluorescent imaging device (100) includes a control unit (109) coupled to the sensors (303a, 303b) for receiving an indication of a sensed coolant fluid leak, the control unit (109) being configured to enter an alarm state in response to the sensed coolant fluid leak.

14. Fluorescence imaging device (100) according to claim 13 when dependent on claim 12, characterized in that The control unit (109) is configured to stop the supply of the coolant fluid from the heat exchanger (169) to the inlet pipe (233i) and / or shut down the power supply to the imaging head (139) in an alarm state.

15. The fluorescence imaging device (100) according to claim 13 or 14 when comprising an imaging head (139) according to any one of claims 5 to 10, characterized in that The suspension structure (136) includes one or more joints (163i, 163o) for rotating the imaging head (139) around a lateral axis perpendicular to the longitudinal axis of the imaging head, and the sensors (303a, 303b) extend along a sensing direction perpendicular to the lateral axis.

16. A method for imaging a body part of a patient in a medical imaging application, characterized in that The method comprises: acquiring one or more fluorescent images of the body part using an imaging head according to any one of claims 1 to 10, and A representation of the body part based on the fluorescent image is output.

17. A medical method comprising: imaging a body part of a patient using the method of claim 16, and A medical procedure associated with the body part is performed based on the representation of the body part.

18. The medical method according to claim 17, characterized in that The medical procedure is a surgical procedure.

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