Patent Publication Number: US-2021161484-A1

Title: Display device for reducing radiation exposure to medical personnel

Description:
RELATED APPLICATIONS 
     This application is a continuation of and claims priority to U.S. patent application Ser. No. 16/055,749 filed Aug. 6, 2018 entitled Display Device for Reducing Radiation Exposure to Medical Personnel, which claims benefit of and priority to U.S. Provisional Application Ser. No. 62/541,367 filed Aug. 4, 2017 entitled Display Device for Reducing Radiation Exposure to Medical Personnel, both of which are hereby incorporated herein by reference in its entireties. 
    
    
     BACKGROUND OF THE INVENTION 
     Radiation exposure for healthcare workers in radiology and cardiology interventional laboratories poses a significant health risk. In one study of cardiology healthcare workers stationed in cardiac catheterization laboratories where x-rays are routinely used for medical procedures (such as angiography, heart biopsy, pacemaker placement, transcatheter stent or heart valve placement, radiofrequency ablation of heart rhythm disorders and right heart catheterization), the risk of cancer was found to be increased three-fold compared to similar workers in areas where radiation is not used. These findings are discussed in Andreassi M G, Piccaluga E, Guagliumi G, et al. Occupational health risks in cardiac catheterization laboratory workers. Circ Cardiovasc Interv. 2016; April; 9(4):e003273; and also in Andreassi M G, Piccaluga E, Guagliumi G, et al. Subclinical carotid atherosclerosis and early vascular aging from long-term low-dose ionizing radiation exposure: a genetic, telomere, and vascular ultrasound study in cardiac catheterization laboratory staff. JACC Cardiovasc Interv. 2015 Apr. 20; 8(4):616-27. 
     Devices to shield worker from x-ray photons are widely used. These vary from x-ray blocking garments worn by workers to shields that hang from the ceiling or rails on the x-ray table or are rolled around the room on a trolley. An ideal shield would be easily positioned from within the sterile field to cover the area of the body being accessed by the physician, allow the physician&#39;s hands to work on the body, permit the physician to visually see the operating field, and move with the patient as the table is repositioned. Although many shields are constructed from x-ray blocking material that transmits the visible light spectrum, these shields are usually attached to the ceiling, roll on the floor, or are attached to the fixed portion of the x-ray table (attached to metal rails on the side of the table). As a result, the shield does not move as the mobile part of the x-ray table is repositioned. In addition, it has been virtually impossible to protect physicians doing procedures next to the patient&#39;s chest or at their head while still allowing visualization and access to the operative field. 
     In addition to the above characteristics of an ideal radiation shield, an overlay of data (such as blood pressure, heart rate, arterial oxygen saturation, or electrocardiogram) or images (such as live ultrasound images or x-ray images) would allow the physician to be informed of the condition of the patient without having to look away from the operating field. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     The invention described herein relates to a repositionable radiation shield device that is transparent, allowing the surgeon to view the operating field while the surgeon&#39;s head and upper chest are protected from scatter radiation. This shield may be easily moved into position by the physician or lab staff from within the sterile field to obtain optimal patient visualization and radiation protection based on the anatomy of the patient being accessed and the position of the physician. Attached to the transparent shield is a display that, when activated, may turn from transparent to opaque or partially transparent shield, allowing the superimposition of data, such as images, physiologic parameters, instructions, image guidance for surgery, or other medical information. Alternatively, the shield may have multiple components, with a clear shield component for viewing the patient and separate non-transparent displays arrayed on the shield to provide patient data. Attached to the shield can also be other features that allow the surgeon to view the operating field better or with added information or images. These features include, but are not limited to the following: 
     Lighting is used to illuminate the area being viewed through the shield. The frequency spectrum of the emitted light may vary from infra-red to ultraviolet to illuminate different structures preferentially. 
     A camera attached to the shield display similarly can allow the surgeon to view the field and, in one embodiment, overlay the imaged field on the shield display. The imaging camera can image at varied frequency spectrums, allowing the surgeon to see various aspects of the field, such as bleeding, temperature differences (such as the heat related to bleeding under the skin), arterial and venous blood flow, and surface contamination (such as using ultraviolet imaging). In addition, such imaging display on the shield could be used in conjunction with other methods described previously, such as fluorescein perfusion imaging. 
     The camera display image can also be co-registered to the operating field, such that the image overlays the visual view of the field seen by the operator through the semi-transparent display. Such co-registration can be accomplished by using fiduciary points in the operating field imaged by the camera. The digital image is then manipulated considering the following factors: 
     The position and angle of the shield relative to the operating field. These factors can be calculated from the camera image of fiduciary points in the operating field, where the points have known positions in space relative to each other. This can be accomplished in a number of ways, including placing a sterile set of three or more physically-connected fiduciary points in the field, a similar marking set, where the points in the field independently or together detect the position and transmit it to a computer, or by the operator identifying by a marking device the position of three or more points with a device that transmits to or is detected by as receiving device that then calculates the position of the markers in space. One additional method to establish fiduciary points and to determine the relationship of the shield display to the imaged surface is to project from the shield display light patterns (such as a grid, cross or crosses, or concentric circles). The geometric distortion of the projected objects can then be used to determine the topography of the imaged field relative to the camera on the shield. 
     In addition, a “heads-up” display without the need for a display alternating between transparent and opaque can be employed. In this embodiment, information is displayed onto the shield for use by the operator. The display can be switched off and on and can be moved about the screen using a touch panel control or through standard switches. 
     Control of the shield display in the operating room environment is best accomplished by switches or control mechanisms that cannot be contaminated or that can be easily cleaned. Control can be accomplished by physical switches on the shield, preferably using switches that can be operated though a sterile barrier (such as a clear bag) surrounding the shield display and are easy to wipe clean, such as membrane touch switches. Alternatively, control devices that do not require physical touch can be employed. These include detectors that identify the position of hands (such as ultrasonic, light, capacitive, or magnetic detectors), or any of a variety of touch switches, or a touchscreen membrane that covers the display shield. 
     The table that patients are lying on during the operation is usually moved in order to x-ray image various parts of the body. To keep the shield in position for the surgeon to view the same part of the body, the shield should move with the patient. In one embodiment, the shield display can be attached to a specialized sled on which the patient lays, an operating table, an x-ray table, or other platform where the shield will move with the patient as the table is moved in and out of the x-ray. The sled contains wiring and electrical power to connect to the display on one end and to the image or data source on the other end. The source can be either a communication cable (such as wired or fiber optic cables) or power supply cable, or a combined cable that is connected to the data source directly, or indirectly (such as through a radiofrequency or infrared connection to the data source). 
     An additional feature is a touchscreen control device overlaid on the display screen or the radiation shield directly. The touchscreen can be of any type (such as resistive, capacitive, or ultrasonic) such that the touchscreen passes visible light through all or a portion of the surface. The touchscreen is connected as an input device to other devices. Such devices include computer monitors, telecommunications devices, and imaging systems. 
     An additional modification of the shielding device is to curve the material such that the shield magnifies the operative field. As an example, this would be useful for surgeries involving small devices or small blood vessels. Magnification can be accomplished optically in a number of ways, including through a curved optical medium attached to the display shield, by curving the radiation shield material, or by curving the transparent display material. Magnification can also be accomplished by magnification of the image obtained from the camera and display of that image on the shield display. One advantage of that method is that the amount of magnification can be varied more easily than changing the optical magnification and the field of magnification can be changed without moving the shield. 
     U.S. Pat. No. 10,106,172 to Wilson et al., and incorporated by reference herein, describes a procedure sled in which the patient lies on a foam-filled carbon fiber shell. The sled described by Wilson et al. has, in one embodiment, rails attached to the outer border of the shell, allowing attachment of devices. In one or more embodiments of the device described herein, the device is mountable to the sled described by Wilson et al. and some of the electronic components are contained within, or attached to the sled. 
     It is recognized that the addition of a display system described herein would facilitate medical procedures in other environments where x-ray imaging is not used, such as operating rooms or emergency rooms, and would not require x-ray shielding. The ability, however, to operate a display, control or imaging system in a sterile field environment where the display, control, or imaging system moved with the patient facilitates the ability of medical personnel in several ways. 
     First, the medical personnel would have the ability to read the display and use the control screen while performing surgery on a patient resting on a moving table. Second, the imaging or camera system can maintain a constant view of the imaged field, where the registration of fiduciary points does not change with patient movement. This maintenance of registration permits more accurate image analysis and allows more accurate assessment of the change in the image over time, such as detecting bleeding through changes in skin topography, for example. 
     Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other aspects, features and advantages of which embodiments of the invention are capable of will be apparent and elucidated from the following description of embodiments of the present invention, reference being made to the accompanying drawings, in which 
         FIG. 1  is a front elevation of an embodiment of a device of the invention; 
         FIG. 2  is a rear elevation of an embodiment of a device of the invention; 
         FIG. 3  is a sectional view of the embodiment of  FIG. 1  taken along section lines  3 - 3 ; 
         FIG. 4  is a front elevation of an embodiment of a system of the invention; 
         FIG. 5  is a perspective view of an embodiment of a system of the invention; 
         FIG. 6  is an end elevation of an embodiment of a system of the invention; 
         FIG. 7  is a perspective view of an embodiment of a system of the invention; 
         FIG. 8  is an end elevation of an embodiment of a system of the invention; 
         FIG. 9  is a perspective view of an embodiment of a system of the invention; 
         FIG. 10  is an end elevation of an embodiment of a system of the invention; and, 
         FIG. 11  is a sectional view of the display of  FIG. 10  taken along section lines  11 - 11 . 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Specific embodiments of the invention will now be described with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The terminology used in the detailed description of the embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like numbers refer to like elements. 
     Referring now to the figures, and first to  FIG. 1 , there is shown an embodiment of a shield  10  of the invention. It can be seen that the shield  10  includes a transparent portion  20 , through which the patient can be seen, and a control portion  30  that includes a plurality of control switches  40 . The control switches  40  control whatever features may be included on the shield. By way of non-limiting example, the embodiment shown in  FIG. 1  may includes a display control  42 , a display “on” switch  44 , an fiduciary point control  46 , a field lighting control  48 , a camera switch  50 , and display source selectors  52 ,  54 ,  56  and  58 . The switches and controls may be physical buttons and knobs or other mechanical devices, or the shield may include touchscreen controls, as is known in the art. The shield may also be voice-activated. One skilled in the art will understand that the controls and functions provided with the shield  10  may be customizable to the needs of the user. The shield  10  may be attached to an arm  60  that is connectable to a hospital bed, equipment stand, fluoroscope, or the like.  FIG. 2  is a back view of the shield  10 , and illustrates the transparent properties of the shield  10 . 
       FIG. 3  depicts a sectional view of the embodiment of the shield  10  taken along section lines  3 - 3  of  FIG. 1 . The section view of  FIG. 3  shows the layered construction of the shield  10 , and includes a transparent touchscreen layer  70 , a transparent computer display  72 , and a transparent radiation shield  74 . The transparent computer display layer  72  may be any clear display technology, such as LED or LCD. 
       FIGS. 4 and 5  show an embodiment of a system  100  of the invention. System  100  includes the shield  10  and a patient platform  110 , which in this case includes a mattress  120 , a sled  130  and an x-ray table  140 . The shield  10  is attached to the arm  60 , which may be articulated as shown. The arm  60  is attached to an attachment rail  150  of the sled  130 . 
       FIGS. 6 and 7  show an embodiment of a system  100  of the invention in which the transparent display  72  of the shield  10  is powered on and is displaying an overlay  80  that includes physiologic data. In at least one embodiment, the opacity of the overlay is adjustable such that the user can adjust how easy it is to see the patient through the display. 
       FIGS. 8 and 9  show an embodiment of a system  100  of the invention in which the transparent display  72  of the shield  10  is powered on and is displaying an overlay  80 , including physiologic data, juxtaposed to a second window  82  showing imaging of the patient. 
       FIG. 10  shows an embodiment of a system  100  of the invention in which the shield  10  includes magnification feature  84 . The magnification feature could be provided electronically, via a projected image using the camera and a zoom feature. Alternatively, as shown in  FIG. 11 . The magnification feature  84  includes a curved magnifying lens layer  76  placed onto the display  10 . The transparent magnifying lens layer  76  may be permanently installed onto the display  10 , or may be an adhesive layer applied to the display  10 . It is also envisioned that the magnifying lens layer  76  be a flat Fresnel lens sheet applied to the display  10 .