Patent Publication Number: US-11647971-B2

Title: Lighting arrangement for a medical imaging system

Description:
TECHNICAL FIELD 
     Aspects of the present invention relate to a lighting arrangement for illuminating a patient tunnel of a medical imaging system, and more particularly, to a lighting arrangement that includes a transparent wall section formed in a wall of the imaging system and a lighting device located adjacent an outer surface of the transparent wall section wherein light emitted by the lighting device is transmitted through the transparent wall section in a direction orthogonal to a longitudinal axis of the tunnel to circumferentially illuminate the tunnel. 
     BACKGROUND 
     Medical imaging systems include a patient bore that receives a patient to be imaged or scanned. The bore is typically elongated and forms a cylindrically shaped patient tunnel through which the patient is moved in a longitudinal direction along a longitudinal axis of the tunnel. The tunnel may be imposing or intimidating to those that are either young or for adults who suffer from claustrophobia, for example. This effect is becoming more pronounced as the average bore length of medical imaging systems, such as positron-emission tomography/computed tomography (PET/CT) systems, is trending longer. In particular, imaging systems having extended axial field-of-views (FoVs), coupled with bore diameters that have remained largely unchanged, have made PET systems less appealing since patients frequently experience a “closed-space feeling” or claustrophobia when located in the tunnel. This is especially true in imaging systems having even longer tunnels such as MR-PET imaging systems and imaging systems having FoVs that are a meter long or more. 
     The addition of light in the tunnel ameliorates the look and feel of the system and gives the tunnel an appearance of being spacious, thus lessening the effects of claustrophobia. For example, lights may be incorporated into the front and back covers of the tunnel. In addition, light projectors located on the longitudinal axis of the tunnel may be used to direct light in a longitudinal direction through the tunnel. 
     SUMMARY OF THE INVENTION 
     A lighting arrangement for a medical imaging system is disclosed wherein the imaging system includes a cylindrical wall that forms a tunnel that receives a patient to be scanned. The lighting arrangement includes a transparent wall section formed in the wall, wherein the transparent wall section extends along a transparent portion of a wall circumference. The imaging system also includes a lighting device located adjacent an outer surface of the transparent wall section. The lighting device extends along a device portion of a wall circumference corresponding to the transparent portion wherein light emitted by the lighting device is transmitted through the transparent wall section in a direction substantially orthogonal to a longitudinal axis of the tunnel to circumferentially illuminate the tunnel. In addition, a system status is indicated by a color of light emitted by the LEDs. Further, light emitted by the lighting device varies in intensity to indicate a changing count rate. 
     In addition, a method of illuminating a tunnel of a medical imaging system is disclosed wherein the imaging system includes a cylindrical wall that forms the tunnel wherein the tunnel receives a patient to be scanned. The method includes providing a transparent wall section in the wall, wherein the transparent wall section extends along a transparent portion of a wall circumference. The method also includes locating a lighting device adjacent an outer surface of the transparent wall section, wherein the lighting device extends along a device portion of a wall circumference corresponding to the transparent portion. Further, the method includes transmitting light emitted by the lighting device through the transparent wall section in a direction substantially orthogonal to a longitudinal axis of the tunnel and circumferentially illuminating the tunnel. In addition, the method includes transmitting a color of light that is indicative of a system status. 
     Those skilled in the art may apply the respective features of the present invention jointly or severally in any combination or sub-combination. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The exemplary embodiments of the invention are further described in the following detailed description in conjunction with the accompanying drawings, in which: 
         FIG.  1    depicts a medical imaging system in accordance with an aspect of the invention. 
         FIG.  2 A  depicts a lighting arrangement in accordance with an aspect of the invention. 
         FIG.  2 B  is an enlarged view of region  2 B of  FIG.  2 A . 
         FIG.  3    is a perspective view of a wall and a lighting device. 
         FIG.  4    depicts a lighting arrangement in accordance with an alternate embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     Although various embodiments that incorporate the teachings of the present disclosure have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings. The scope of the disclosure is not limited in its application to the exemplary embodiment details of construction and the arrangement of components set forth in the description or illustrated in the drawings. The disclosure encompasses other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. 
     Referring to  FIG.  1   , a view of an exemplary medical imaging system  10  in accordance with an aspect of the invention is shown. The invention may be used in conjunction with any medical imaging system  10  having a patient tunnel for receiving a patient such as a magnetic resonance imaging (MRI) system, a positron emission tomography (PET) system, a single-photon emission computed tomography (SPECT) system, a PET/MRI system, an X-ray computed tomography (CT) system, a PET/CT system, a SPECT/CT system and others. For purposes of illustration, the invention will be described in connection with a PET/CT imaging system  12  having a CT portion  14  and a PET portion  16 . The CT portion  14  includes a recording unit, comprising an X-ray source  18  and an X-ray detector  20 . The recording unit rotates about a longitudinal axis  22  during the recording of a tomographic image, and the X-ray source  18  emits X-rays  24  during a recording. While an image is being recorded a patient  26  lies on a patient bed  28 . The bed  28  is connected to a table base  30  such that it supports the bed  28  bearing the patient  26 . The bed  28  is designed to move the patient  26  along a recording direction through an opening or tunnel  32  of a gantry  34  of the system  12 . The table base  30  includes a control unit  34  connected to a computer  36  to exchange data. In the example shown in  FIG.  1   , a medical diagnostic or therapeutic unit is designed in the form of a system  12  by a determination unit  38  in the form of a stored computer program that can be executed on the computer  36 . The computer  36  is connected to an output unit  40  and an input unit  42 . The output unit  40  is, for example, one (or more) liquid crystal display (LCD) or plasma screen(s). An output  44  on the output unit  40  comprises, for example, a graphical user interface for actuating the individual units of the system  12  and the control unit  34 . Furthermore, different views of the recorded data can be displayed on the output unit  40 . The input unit  42  is for example a keyboard, mouse, touch screen or a microphone for speech input. 
       FIG.  2 A  depicts a schematic cross-sectional side view of the tunnel  32 . The tunnel  32  is defined by a substantially cylindrical tunnel wall  46  having outer  48  and inner  50  surfaces. The CT portion  14  includes a CT field of view  52  having a first width  54  and the PET portion  16  includes a PET field of view  56  having a second width  58 . The CT  14  and PET  16  portions are sensitive to X-rays and gamma rays, respectively, via the CT  52  and PET  56  fields of view, respectively. In accordance with an aspect of the invention, a lighting device  60  is located adjacent to or on the outer surface  48  of the wall  46  and between the CT  52  and PET  56  fields of view. The lighting device  60  is also located outside of the first  54  and second  58  widths of the CT  52  and PET  56  fields of view, respectively, so that X-rays and gamma rays generated by the system  12  are not affected by the lighting device  60 .  FIG.  3    is a perspective view of the wall  46  and the lighting device  60 . Referring to  FIG.  3    in conjunction with  FIG.  2 A , the lighting device  60  may extend around an entire circumference of the outer surface  48  of the wall  46  to form a substantially ring-shaped configuration around the wall  46  having a central angle of 360 degrees. Alternatively, the lighting device  60  may extend only partially around the circumference of the outer surface  48  to form a semicircular (i.e. approximately 180 degrees) shape or an arc shape of either more or less than 180 approximately degrees. 
       FIG.  2 B  is an enlarged view of region  2 B of  FIG.  2 A . Referring  FIGS.  2 A and  2 B , the lighting device  60  includes a light source  62  located between first  64  and second  66  reflector elements that extend toward the outer surface  48  and contact the outer surface  48 . The first  64  and second  66  reflector elements include first  68  and second  70  mirror surfaces, respectively, located to reflect light emitted by the light source  62 . In an alternate embodiment, additional or fewer reflector elements and/or mirror surfaces may be used. The wall  46  includes a window or transparent wall section  72  having transparent outer  74  and inner  76  surfaces. In accordance with an aspect of the invention, the transparent inner surface  76  is aligned with the inner surface  50  of the wall  46  to form a continuously smooth inner surface. This reduces the likelihood that the patient  26  is caught or snagged when the patient  26  is moved in and out of the tunnel  32  and facilitates equipment hygiene. The transparent wall section  72  is aligned with the lighting device  60  to form a lighting arrangement  78  for illuminating the tunnel  32 . In an embodiment, a light diffuser may be used instead of, or in addition to, the transparent wall section  72 . 
     Light  80  emitted by the light source  62  travels toward the transparent wall section  72  and is reflected by the first  68  and second  70  mirror surfaces toward the transparent wall section  72 . Light  80  is then transmitted through the transparent wall section  72  in a direction substantially orthogonal to the longitudinal axis  22  and into the tunnel  32  to illuminate the tunnel  32 . Alternatively, light  80  may be oriented at an angle other than an orthogonal angle relative to the longitudinal axis  22 . The light source  62  may be a strip of lights, a fiber optic light rope or a strip of red, green, blue (RGB) light emitting diodes (LEDs) or other light source that emits a broad light spectrum. 
     In an embodiment, the transparent wall section  72  corresponds to the circumferential shape of the lighting device  60 . For example, the transparent wall section  72  and the lighting device  60  may both be ring-shaped such that light is transmitted through the entire circumference (i.e. 360 degrees) and into the tunnel  32  to circumferentially illuminate the tunnel  32 . In an embodiment, the first  64  and second  66  reflector elements are sloped away from each other in order to provide a relatively wide-angle light beam in the tunnel  32 . Alternatively, the first  64  and second  66  reflector elements may be oriented to provide other beam angles as desired, such as a relatively narrow beam angle. 
     Illumination of the tunnel  32  ameliorates the look and feel of the tunnel  32  and gives the tunnel  32  an appearance of being spacious to the patient  26 , thus lessening the effects of claustrophobia and calming the patient  26 . Further, the lighting arrangement  78  is located outside of both the CT  52  and PET  56  fields of view (i.e. outside of an imaging volume) and thus does not influence the X-rays or gamma rays generated by the system  12  and avoids attenuation and scatter of the signals. 
     In addition to illuminating the tunnel  32 , the lighting arrangement  78  may be used to generate light that serves as a parameter indicator for a clinician or operator so that the operator is able to readily observe a status of the system  12  without having to be located at terminal or output unit  40  of the system  12 . In accordance with an aspect of the invention, lighting in the tunnel  32  may be varied in intensity according to an amount of activity measured by the PET portion  16  such as a changing count rate. In addition, the lighting device  60  may provide color lighting indicative of a system status or mode to indicate that the system is on, idling, running, that the bed  28  or a patient handling system is in motion and others. 
     Different color lighting may be used to indicate the health of the system. For example, upon startup of the system  12 , green lighting may be used to indicate a normal system operating status (i.e. ready to scan, no system issue detected and others), yellow lighting to indicate a system warning that needs attention, red lighting to indicate a system failure that needs to be resolved and blue lighting to indicate that the system  12  is in a power save mode. Further, different color lighting may be used to indicate a message or instruction to the patient. For example, a first color may be used to indicate to the patient to hold their breath, a second color to indicate to the patient that they should breathe and other colors may be used to indicate other messages. In addition, the light source  62  may be arranged in a panel configuration to form separate LEDs that each serve as pixels on a text screen. This enables the display of messages on the screen that are helpful to a patient  26  that has hearing loss or useful for studying a patient&#39;s auditory system response. For example, the messages indicating a patient instruction such as “breathe”, “stop breathing”, or a message indicating scan time, remaining scan time and others may be displayed on the screen. The computer  36  may be used to control activation and operation of the light source  62 . 
     Referring to  FIG.  4   , a lighting arrangement  82  for illuminating the tunnel  32  in accordance with an alternate embodiment of the invention is shown. Lighting device  84  includes at least one lighting element  86  inserted into a rope or light strip  88  of substantially transparent fiber optic material. In an embodiment, the lighting element  86  includes at least one RGB LED or other light source that emits different color light. The strip  88  is located on the transparent outer surface  74  and may extend around the entire circumference of the transparent outer surface  74  of the transparent wall section  72  to form a ring-shaped configuration having a central angle of 360 degrees around the wall  46 . Alternatively, the strip  88  may extend only partially around the circumference of the transparent outer surface  74  to form a semicircular (i.e. approximately 180 degrees) shape or an arc shape of either more or less than 180 approximately degrees. More than one strip  88  may be positioned around the circumference of the transparent outer surface  74  such that the strips  88  are positioned side by side on the transparent outer surface  74  to a desired width. The strips  88  are located outside of the first  54  and second  58  widths of the CT  52  and PET  56  fields of view, respectively, so that X-rays and gamma rays generated by the system  12  are not affected by the strips  88 . In an embodiment, light  80  emitted by the lighting device  84  is transmitted through the transparent wall section  72  in a direction substantially orthogonal to the longitudinal axis  22  such that light is transmitted through the entire circumference (i.e. 360 degrees) and into the tunnel  32  to circumferentially illuminate the tunnel  32 . Alternatively, light  80  may be oriented at an angle other than an orthogonal angle relative to the longitudinal axis  22 . 
     While particular embodiments of the present disclosure have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the disclosure. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this disclosure.