System and method of generating a color-coded image demonstrating blood flow

Abstract

A method and a system of generating a color-coded image demonstrating blood flow in a chosen area in a patient, specifically for diagnosing medical conditions like ischemia, strokes and infarcts. A plurality of images, preferably 3, are taken at different points in time that are a few seconds apart, and colorized by different colors, preferably a first image red, a second image blue and a third image green. These colorized images are then aligned and summated to create a multicolor image that time encodes perfusion of blood. Preferably, said method is performed after injection of a contrast agent.

Claims

1. A method of generating a color-coded multicolor image demonstrating blood flow in a chosen area in a patient, said method comprising: i) taking a first image at a first point in time; ii) taking a second image at a second point in time that is later than the first point in time; iii) coloring the first image by a first color to create a first colorized image; iv) coloring the second image by a second color to create a second colorized image; v) aligning the first and the second colorized images so that the first and second colorized images are congruent; vi) summating the congruently aligned first and second colorized images to create a multicolor image showing colors created by the summation of the first and second color.

2. The method according to claim 1, further comprising: vii) taking a third image at a third point in time that is later than the second point in time; viii) coloring the third image by a third color to create a third colorized image; ix) aligning the first, second and third colorized images so that the first, second and third colorized images are congruent; x) summating the congruently aligned first, second and third colorized images to create a multicolor image showing colors created by the summation of the first, second and third colors.

3. The method according to claim 1, wherein the first color is red and the second color is blue.

4. The method according to claim 2, wherein the first color is red, the second color is blue, and the third color is green.

5. The method according to claim 4, wherein no additional images beyond the first, second and third colorized images are summated.

6. The method according to claim 1, wherein the entire respective images are colorized by the respective colors.

7. The method according to claim 1, wherein the summation of the colorized images is a plain summation without applying any other mathematical algorithms such as calculation of histograms, deconvolution, or application of calculus.

8. The method according to claim 1, wherein the images are taken at subsequent points in time that are between 1 and 10 seconds apart from each other.

9. The method according to claim 1, further comprising injection of a contrast agent prior to performing any of the steps i) through x).

10. The method according to claim 9, wherein the method is applied in one of a group consisting of: CT angiograms, catheter angiograms, MR angiograms, barium studies, interventional fluoroscopic procedures that use contrast, and ultrasound with the use of ultrasound contrast.

11. The method according to claim 1, wherein the method is an interventional fluoroscopic procedure including devices that are visible on X-ray.

12. The method according to claim 1, wherein the method is an ultrasound procedure in connection with motion.

13. The method according to claim 1, wherein the method is applied in dynamic systems that do not use injected contrast agents.

14. The method according to claim 13, wherein the method is applied in MRI techniques making moving blood or CSF visible.

15. The method according to claim 10, wherein the method is applied to a gray scale image where each gray pixel is created by subpixels of red, green, and blue light of different intensity levels of less than 100 percent luminosity resulting in gray rather than white as would be the case if all intensities are set at a 100 percent luminosity, wherein for coloring the first image red, a computer program coloring algorithm turns off the blue and green subpixels by setting blue and green subpixel light intensities to zero; for coloring the second image blue, a computer program coloring algorithm turns off the red and green subpixels by setting red and green subpixel light intensities to zero; and for coloring the third image green, a computer program coloring algorithm turns off the red and blue subpixels by setting red and blue subpixel light intensities to zero.

16. A system for taking and processing images for demonstrating blood flow in a chosen area in a patient by generating a color-coded multicolor image demonstrating such blood flow, said system comprising: an imaging device configured to take images of the chosen area in a patient including at least a first image at a first point in time and a second image at a second point in time, wherein the first and second points in time are set apart by 1 s-10 s; a computer programmed to: color the first image with a first color to create a first colorized image and the second image with a second color to create a second colorized image; align the first and the second colorized images so that the first and second colorized images are congruent; and summate the congruently aligned first and second colorized images generating a multicolor image showing colors created by the summation of the first and second color; and a display device displaying the multicolor image.

17. The system according to claim 16, wherein said imaging device is configured to take a third image at a third point in time that is set apart from second point in time by 1 s-10 s; and said computer is further programmed to: color the third image with a third color to create a third colorized image; align the first, second and third colorized images so that all 3 images are congruent; and summate the congruently aligned 3 colorized images generating a multicolor image showing the first, second and third colors and colors created by the summation.

18. The system according to claim 16, wherein the computer is programmed to color the first image red and the second image blue.

19. The system according to claim 17, wherein the computer is programmed to color the first image red, the second image blue and the third image green.

20. The system according to claim 19, wherein the computer is programmed to summate just the first, second and third colorized images and no additional images and to color all three images in their entirety by the respective colors.

21. The system according to claim 16, wherein the summation of the colorized images is a plain summation without applying any other mathematical algorithms such as calculation of histograms, deconvolution, or application of calculus.

22. The system according to claim 16, further comprising an injection apparatus configured to inject a contrast agent into the patient prior to taking images by the imaging device.

23. The system according to claim 22, wherein the imaging device is one of a group consisting of: CT angiogram imaging device, catheter angiogram imaging device, MR angiogram imaging device, barium studies imaging device, interventional fluoroscopic procedures imaging device that use contrast, and ultrasound imaging device with the use of ultrasound contrast.

24. The system according to claim 16, wherein the imaging device is an interventional fluoroscopic procedure imaging device including devices that are visible on X-ray.

25. The system according to claim 16, wherein the imaging device is an ultrasound procedure imaging device configured to image in connection with motion.

26. The system according to claim 16, wherein the imaging device is applied in dynamic systems that do not use injected contrast agents.

27. The system according to claim 26, wherein the imaging device is an MRI imaging device configured to making moving blood or CSF visible.

28. The system according to claim 19, wherein the method is applied to a gray scale image where each gray pixel is created by subpixels of red, green, and blue light of different intensity levels of less than 100 percent luminosity resulting in gray rather than white as would be the case if all intensities are set at a 100 percent luminosity, wherein the computer is further programmed to perform a computer program coloring algorithm for coloring said first, second and third images by: for coloring the first image red, said computer program coloring algorithm turning off the blue and green subpixels by setting blue and green subpixel light intensities to zero; for coloring the second image blue, said computer program coloring algorithm turning off the red and green subpixels by setting red and green subpixel light intensities to zero; and for coloring the third image green, said computer program coloring algorithm turning off the red and blue subpixels by setting red and blue subpixel light intensities to zero.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] FIG. 1 demonstrates generating a multicolor image generated according to the invention to color an area where a stroke happened;

[0046] FIG. 2 shows a block diagram demonstrating the method according to the invention applying 2 colors;

[0047] FIG. 3 shows a block diagram demonstrating the method according to the invention applying 2 colors;

[0048] FIG. 4 depicts the principle of color summation and the resulting colors generated; and

[0049] FIG. 5 is a schematic diagram of a system for generating a multicolor image generated according to the invention for visualizing blood flow in a patient.

DETAILED DESCRIPTION OF THE DRAWINGS

[0050] FIG. 1 shows how this color summation principle demonstrated in FIG. 4 is applied according to the invention on coloring a CT for demonstrating blood flow in a brain 2 of a patient, specifically a patient who has suffered a stroke. After injection of a contrast agent, at a first point in time t.sub.0 a first image 1 is generated by the CT scan. CT scans generate gray scale images. The outer white rim shows the skull 3 white due to comprising dens bone.

[0051] After a delay t.sub.1 a second image 4 is taken at the point in time t.sub.1=t.sub.0+t.sub.1, like all CT images in gray scale. As the blood marked by the contrast agent perfuses through the brain, the image 4 differs from the image 1 in that the blood flow has meanwhile progressed during the time t.sub.1 that has lapsed between the point in time t.sub.0 when the first image 1 was taken and point in time t.sub.1 when the second image 4 was taken.

[0052] Finally, at the point in time t.sub.2=t.sub.1+t.sub.2 a third image 5 was taken after a second delay in time t.sub.2. t.sub.2 could be equal to t.sub.1, longer than t.sub.1 or shorter than t.sub.1. However, both t.sub.1 and t.sub.2 are in a range of a few seconds, for example 3 seconds, for capturing the progress of the perfusion.

[0053] Coloring the first image 1 red generates the red colored image 6. The red color is coded by a first hatching 7 demonstrating the color red.

[0054] Coloring the second image 2 blue generates the blue colored image 8. The blue color is coded by a second hatching 9 demonstrating the color blue.

[0055] Coloring the third image 5 green generates the green colored image 10. The blue color is coded by a third hatching 14, which is a crosshatching, demonstrating the color green.

[0056] Next, the colored images 6, 8 and 10 are summated, resulting in the multicolor image 11. An area where the blood flow arrives last shows predominantly or exclusively green, namely blood that only arrived in the respective area at the last point in time, denoted by reference numeral 12. The remaining area shows typically in some shade of purple generated by the summation of the colors red and blue, meaning that the blood arrived in these areas 13 sooner than in the area 12. Although the resulting multicolor image 11 should show all 3 hatchings (vertical hatching, horizontal hatching and crosshatching), demonstrating all 3 colors at different intensities in different areas in the multicolor image 11, for simplicity only the green hatching is shown, showing the area 13 where the blood flow arrived last and which might indicate ischemia or stroke. The general concept of color summation is demonstrated in FIG. 4. Notably, the colorized images 6 and 8 colorized red and blue do not show any hatchings in the area designated 12 in the multicolor image 11 showing green. In an embodiment where a contrast agent is used, this contrast agent has not or has only insufficiently arrived at the area 12 at the times t.sub.0 and t.sub.1, and substantially arrived there at the time t.sub.2, which is color-coded green. If by the time t.sub.2 all the contrast agent that was present at time t.sub.0 and t.sub.1 has vanished, then only the area 12 shows green and should show crosshatching in the colorized image 10, like in the multicolor image 11. In case there is some overlap, meaning some of the contrast agent present at respective areas at the times t.sub.0 and t.sub.1 is still present at time t.sub.2, a resulting mixed color would show in such areas. FIG. 1 is a simplified depiction for demonstrating the main effects that are accomplished by the colorizing and color summation, but it needs to be understood that in practical applications, several different color shades show throughout the multicolor image 11, not just in one area 12 that is green or predominantly green as in the discussed embodiment.

[0057] The image 11 allows the doctor or other medical technician to identify problematic areas, for example ischemic tissue or tissue where a stroke has happened. In contrast, if no medical condition is present, the color is balanced.

[0058] Of note, the skull 3 shows white also in the multicolor image 11 due to the high bone density of the skull, hiding the contrast agent that would otherwise show in the skull area and demonstrate blood flow in the skull marrow.

[0059] FIG. 2 shows a flowchart listing the steps for combining two images to generate a color-coded multicolor image demonstrating blood flow in a chosen area in a patient, according to method 200.

[0060] In step 202, a first image 1, 501 may be taken at a first point in time.

[0061] In step 204, a second image 4, 504 may be taken at a second point in time that is later than the first point in time.

[0062] In step 206, the first image 1, 501 may be colored a first color, thereby creating a first colorized image 6, 506.

[0063] In step 208, the second image 4, 504 may be colored a second color, thereby creating a second colorized image 8, 508.

[0064] In step 210, the first colorized image 6, 506 and the second colorized image 8, 508 may be aligned so that the first colorized image 6, 506 and second colorized image 8, 508 are congruent.

[0065] In step 212, the congruently aligned first colorized image 6, 506 and second colorized image 8, 508 may be summated to create a multicolor image 11, 511 showing colors created by the summation of the first color and second color. In areas where the intensity of the second color is zero, the color created by the color summation is the first color, which conversely, in areas where the intensity of the first color is zero, the color created by the color summation is the second color.

[0066] FIG. 3 shows a flowchart listing the steps for combining three images to generate a color-coded multicolor image demonstrating blood flow in a chosen area in a patient, according to method 300.

[0067] In step 302, a first image 1, 501 may be taken at a first point in time.

[0068] In step 304, a second image 4, 504 may be taken at a second point in time that is later than the first point in time.

[0069] In step 306, a third image 5, 505 may be taken at a third point in time that is later than the second point in time.

[0070] In step 308, the first image 1, 501 may be colored a first color, thereby creating a first colorized image 6, 506.

[0071] In step 310, the second image 4, 504 may be colored a second color, thereby creating a second colorized image 8, 508.

[0072] In step 312, the third image 5, 505 may be colored a third color, thereby creating a third colorized image 10, 510.

[0073] In step 314, the first colorized image 6, 506, the second colorized image 8, 508, and the third colorized image 10, 510 may be aligned so that the first colorized image 6, 506, the second colorized image 8, 508, and the third colorized image 10, 510 are congruent.

[0074] In step 316, the congruently aligned first colorized image 6, 506, second colorized image 8, 508, and third colorized image 10, 510 may be summated to create a multicolor image 11, 511 showing colors created by the summation of the first, second, and third colors. In areas where the intensities of the first and second color are zero, the color created by the color summationas perceived by the retina of the human eyeis the third color. In areas where the intensities of the second and third colors are zero, the color created by the color summation is the first color. Finally, in areas where the intensities of the first and third colors are zero, the color created by the color summation is the second color. However, it is possible that some level of intensities of all three colors are present in all areas, in which case the pure first, second and third colors do not show in the multicolor image created by color summation, just mixed colors throughout the multicolor image, including the color white in areas where all 3 colors are present at the same intensities.

[0075] FIG. 4 depicts the principle of color summation and the resulting colors generated. As shown in FIG. 4, it is assumed that the light intensity of all three colors red, green and blue are approximately the same. Superimposing green and blue light at approximately the same light intensities creates the color cyan, red and blue the color magenta, and green and red the color yellow. Summating all three colors at approximately the same light intensities creates the color white. In FIG. 4, the white area in the middle should show the hatchings demonstrating all three colors by vertical hatching, horizontal hatching and crosshatching, but it is left white for better demonstration of the color white.

[0076] FIG. 5 shows system 500 for taking and processing images for demonstrating blood flow in a chosen area in a patient by generating a color-coded multicolor image 511 demonstrating such blood flow. The system 500 may include an imaging device 520 configured to capture a plurality of images, for instance a first image 501, a second image 504, and a third image 505. In a preferred embodiment, the imaging device 520 is a computed tomography (CT) scanner configured to obtain detailed internal images of a patient's body. However, the imaging device 520 may alternatively be any imaging apparatus suitable for imaging relevant parameters of a body.

[0077] The plurality of images 501, 504, 505 is taken at temporally-spaced intervals, for example with intervening time delays between one second and ten seconds, but for certain applications a greater or lesser time delay may be advantageous. Each of the images 501, 504, 505 captures the same area of the patient's body, such that the images 501, 504, 505 may subsequently overlaid in order to visually represent changes over time.

[0078] The plurality of images 501, 504, 505 may be transmitted from the imaging device 520 to a computer 530 in a conventional manner. The computer 530 may be configured to perform a sequence of functions on the images received from the imaging device 520. First, the computer 530 may colorize each of the images with a respective color. The first image 501 may for instance be colorized red (denoted by a dot pattern), thereby generating a first colorized image 506. The second image 504 may for instance be colorized blue (denoted by a plaid pattern), thereby generating a second colorized image 508. The third image 505 may for instance be colorized green (denoted by a diagonal stripe pattern), thereby generating a third colorized image 510. Next, the first colorized image 506, the second colorized image 508, the third colorized image 510 are overlaid such that common elements between the images are aligned. Subsequently, a multicolor image 511 is generated by summating the respective colorized images 506, 508, 510.

[0079] The multicolor image 511 may be transmitted from the computer 530 to a display device 540 in a conventional manner. The multicolor image 511 may be displayed on the display device 540, where it may for instance be viewed and analyzed by a healthcare professional.

[0080] In the following, additional embodiments of the invention are described:

[0081] Embodiment 1. An embodiment of a method of generating a color-coded multicolor image demonstrating blood flow in a chosen area in a patient, said method comprising: [0082] i) taking a first image 1, 501 at a first point in time to; [0083] ii) taking a second image 4, 504 at a second point in time t.sub.1 that is later than the first point in time to; [0084] iii) coloring the first image 1, 501 by a first color to create a first colorized image 6, 506; [0085] iv) coloring the second image 4, 504 by a second color to create a second colorized image 8, 508; [0086] v) aligning the first and the second colorized images 6, 8 so that the first and second colorized images 6, 506; 8, 508 are congruent; [0087] vi) summating the congruently aligned first and second colorized images 6, 506; 8, 508 to create a multicolor image 11, 511 showing the first color, second color, and colors created by the summation of the first and second color.

[0088] Embodiment 2. The method according to embodiment 1, further comprising: [0089] vii) taking a third image 5, 505 at a third point in time t.sub.2 that is later than the second point in time t.sub.1; [0090] viii) coloring the third image 5, 505 by a third color to create a third colorized image 10; [0091] ix) aligning the first, second and third colorized images 6, 506; 8, 508; 10, 510 so that the first, second and third colorized images 6, 506; 8, 508; 10, 510 are congruent; [0092] x) summating the congruently aligned first, second and third colorized images 6, 506; 8, 508; 10, 510 to create a multicolor image 11, 511 showing the first color, second color, third color and colors created by the summation of the first, second and third colors.

[0093] Embodiment 3. The method according to embodiment 1, wherein the first color is red and the second color is blue.

[0094] Embodiment 4. The method according to embodiment 2, wherein the first color is red, the second color is blue, and the third color is green.

[0095] Embodiment 5. The method according to embodiment 4, wherein no additional images beyond the first, second and third colorized images 6, 506; 8, 508; 10, 510 are summated.

[0096] Embodiment 6. The method according to any one of embodiments 1-5, wherein the entire respective images are colorized by the respective colors.

[0097] Embodiment 7. The method according to any one of embodiments 1-6, wherein the summation of the colorized images 6, 8, 10 is a plain summation without applying any other mathematical algorithms such as calculation of histograms, deconvolution, or application of calculus.

[0098] Embodiment 8. The method according to any one of embodiments 1-7, wherein the images are taken at subsequent points in time that are between 1 and 10 seconds apart from each other.

[0099] Embodiment 9. The method according to any one of embodiments 1-8, further comprising injection of a contrast agent prior to performing any of the steps i) through x).

[0100] Embodiment 10. The method according to embodiment 9, wherein the method is applied in one of a group consisting of: CT angiograms, catheter angiograms, MR angiograms, barium studies, interventional fluoroscopic procedures that use contrast, and ultrasound with the use of ultrasound contrast.

[0101] Embodiment 11. The method according to any one of embodiments 1-8, wherein the method is an interventional fluoroscopic procedure including devices that are visible on X-ray.

[0102] Embodiment 12. The method according to any one of embodiments 1-8, wherein the method is an ultrasound procedure in connection with motion.

[0103] Embodiment 13. The method according to any one of embodiments 1-8, wherein the method is applied in dynamic systems that do not use injected contrast agents.

[0104] Embodiment 14. The method according to embodiment 13, wherein the method is applied in MRI techniques making moving blood or CSF visible.

[0105] Embodiment 15. The method according to embodiment 10, wherein [0106] the method is applied to a gray scale image where each gray pixel is created by subpixels of red, green, and blue light of different intensity levels of less than 100 percent luminosity resulting in gray rather than white as would be the case if all intensities are set at a 100 percent luminosity, wherein [0107] for coloring the first image 1, 501 red, a computer program coloring algorithm turns off the blue and green subpixels by setting blue and green subpixel light intensities to zero; [0108] for coloring the second image 4, 504 blue, a computer program coloring algorithm turns off the red and green subpixels by setting red and green subpixel light intensities to zero; and [0109] for coloring the third image 5, 505 green, a computer program coloring algorithm turns off the red and blue subpixels by setting red and blue subpixel light intensities to zero.

[0110] Embodiment 16. A system for taking and processing images for demonstrating blood flow in a chosen area in a patient by generating a color-coded multicolor image demonstrating such blood flow, said system comprising: [0111] an imaging device 520 configured to take images of the chosen area in a patient including at least a first image 1, 501 at a first point in time to and a second image 4, 504 at a second point in time t.sub.1, wherein the first and second points in time are set apart by 1 s-10 s; [0112] a computer 530 programmed to: [0113] color the first image 1, 501 with a first color to create a first colorized image 6, 506 and the second image 4, 504 with a second color to create a second colorized image; [0114] align the first and second colorized images so that the first and second colorized images 6, 506; 8, 508 are congruent; and [0115] summate the congruently aligned first and second colorized images 6, 506; 8, 508 generating a multicolor image 11, 511 showing the first color, second color, and colors created by the summation of the first and second color; and [0116] a display device 540 displaying the multicolor image 11, 511.

[0117] Embodiment 17. The system according to embodiment 16, wherein [0118] said imaging device 520 is configured to take a third image 5, 505 at a third point in time t.sub.2 that is set apart from second point in time t.sub.1 by 1 s-10 s; and [0119] said computer 530 is further programmed to: [0120] color the third image 5, 505 with a third color to create a third colorized image 10; [0121] align the first, second and third colorized images 6, 506; 8, 508; 10, 510 so that all 3 images are congruent; and [0122] summate the congruently aligned 3 colorized images generating a multicolor image showing the first, second and third colors and colors created by the summation.

[0123] Embodiment 18. The system according to embodiment 16, wherein the computer 530 is programmed to color the first image 1, 501 red and the second image 4, 504 blue.

[0124] Embodiment 19. The system according to embodiment 17, wherein the computer 530 is programmed to color the first image 1, 501 red, the second image 4, 504 blue and the third image 5, 505 green.

[0125] Embodiment 20. The system according to embodiment 19, wherein the computer 530 is programmed to summate just the first, second and third colorized images 6, 506; 8, 508; 10, 510 and no additional images and to color all three images in their entirety by the respective colors.

[0126] Embodiment 21. The system according to any one of embodiments 16-20, wherein the summation of the colorized images is a plain summation without applying any other mathematical algorithms such as calculation of histograms, deconvolution, or application of calculus.

[0127] Embodiment 22. The system according to any one of embodiments 16-21, further comprising an injection apparatus configured to inject a contrast agent into the patient prior to taking images by the imaging device 520.

[0128] Embodiment 23. The system according to embodiment 22, wherein the imaging device 520 is one of a group consisting of: CT angiogram imaging device, catheter angiogram imaging device, MR angiogram imaging device, barium studies imaging device, interventional fluoroscopic procedures imaging device that use contrast, and ultrasound imaging device with the use of ultrasound contrast.

[0129] Embodiment 24. The system according to any one of embodiments 16-21, wherein the imaging device 520 is an interventional fluoroscopic procedure imaging device including devices that are visible on X-ray.

[0130] Embodiment 25. The system according to any one of embodiments 16-21, wherein the imaging device 520 is an ultrasound procedure imaging device configured to image in connection with motion.

[0131] Embodiment 26. The system according to any one of embodiments 16-21, wherein the imaging device 520 is applied in dynamic systems that do not use injected contrast agents.

[0132] Embodiment 27. The system according to embodiment 26, wherein the imaging device 520 is an MRI imaging device configured to making moving blood or CSF visible.

[0133] Embodiment 28. The system according to any one of embodiments 19-23, wherein [0134] the method is applied to a gray scale image where each gray pixel is created by subpixels of red, green, and blue light of different intensity levels of less than 100 percent luminosity resulting in gray rather than white as would be the case if all intensities are set at a 100 percent luminosity, wherein [0135] the computer 530 is further programmed to perform a computer program coloring algorithm for coloring said first, second and third images by: [0136] for coloring the first image 1, 501 red, said computer program coloring algorithm turning off the blue and green subpixels by setting blue and green subpixel light intensities to zero; [0137] for coloring the second image 4, 504 blue, said computer program coloring algorithm turning off the red and green subpixels by setting red and green subpixel light intensities to zero; and [0138] for coloring the third image green, said computer program coloring algorithm turning off the red and blue subpixels by setting red and blue subpixel light intensities to zero.

[0139] The following is a list of reference numerals as shown in the drawings: [0140] 1 first image [0141] 2 brain [0142] 3 skull [0143] 4 second image [0144] 5 third image [0145] 6 first colorized image [0146] 7 first hatching [0147] 8 second colorized image [0148] 9 second hatching [0149] 10 third colorized image [0150] 11 multicolor image [0151] 12 first area [0152] 13 second area [0153] 14 third hatching [0154] 200 method [0155] 202 method step [0156] 204 method step [0157] 206 method step [0158] 208 method step [0159] 210 method step [0160] 212 method step [0161] 300 method [0162] 302 method step [0163] 304 method step [0164] 306 method step [0165] 308 method step [0166] 310 method step [0167] 312 method step [0168] 314 method step [0169] 316 method step [0170] 318 method step [0171] 500 system [0172] 501 first image [0173] 504 second image [0174] 505 third image [0175] 506 first colorized image [0176] 508 second colorized image [0177] 510 third colorized image [0178] 511 multicolor image [0179] 520 imaging device [0180] 530 computer [0181] 540 display device