FORECAST OF MRI IMAGES BY MEANS OF A FORECAST MODEL TRAINED BY SUPERVISED LEARNING

Abstract

The present disclosure deals with the quickening of MRI examinations. Subjects of the present disclosure are a method, a system, a computer program product, a use, a contrast agent for use and a kit.

Claims

1. A computer-implemented method comprising: receiving a plurality of MRI images, at least some of the MRI images showing an examination region during a first time span after administering a contrast agent, feeding the plurality of MRI images to a prediction model, the prediction model having been trained by means of supervised learning to predict, on the basis of MRI images, at least some of which show an examination region during a first time span after administering a contrast agent, one or more MRI images showing the examination region during a second time span, the second time span following the first time span chronologically, generating one or more predicted MRI images showing the examination region during a second time span by means of the prediction model, the second time span following the first time span chronologically, and displaying and/or outputting the one or more predicted MRI images and/or storing the one or more predicted MRI images in a data storage medium.

2. The method of claim 1, wherein at least one received MRI image shows the examination region before administering the contrast agent and at least one received MRI image shows the examination region after administering the contrast agent.

3. The method of claim 1, wherein the examination region is a liver or a portion of a liver of a mammal, preferably a human.

4. The method of claim 3, wherein the first time span is chosen such that it shows the examination region in different phases, wherein the phases comprise a native phase, an arterial phase, a portal-vein phase and a late phase, wherein at least one MRI image is received which shows the examination region in the native phase, and at least one MRI image is received which shows the examination region during the arterial phase, and at least one MRI image is received which shows the examination region in the portal-vein phase, and at least one MRI image is received which shows the examination region in the late phase.

5. The method of claim 1, wherein the plurality of MRI images show a liver or a portion of a liver of a mammal prior to a time point TP0 and during a time span from TP0 to TP1 and/or during a time span from TP1 to TP2 and/or during a time span from TP2 to TP3 and/or during a time span from TP3 to TP4, at time point TP0 the contrast agent being administered intravenously as a bolus and then reaching liver cells via liver arteries and liver veins, at time point TP1 the contrast agent in the liver arteries reaching a maximum concentration, at time point TP2 a signal intensity generated in the liver veins by the contrast agent assuming a value which is the same size as a value of a signal intensity generated in the liver arteries by the contrast agent, at time point TP3 the contrast agent in the liver veins reaching a maximum concentration, at time point TP4 a signal intensity generated in the liver cells by the contrast agent assuming a value which is the same size as a value of a signal intensity generated in the liver veins by the contrast agent.

6. The method of claim 1, wherein the first time span starts within a time span of from one minute to one second before the administration of the contrast agent or with the administration of the contrast agent, and lasts for a time span of from 2 minutes to 15 minutes, preferably 2 minutes to 13 minutes, yet more preferably 3 minutes to 10 minutes, from the administration of the contrast agent.

7. The method of claim 1, wherein the second time span is within a hepatobiliary phase.

8. The method of claim 1, wherein the second time span starts at least 10 minutes after administration of the contrast agent, preferably at least 20 minutes after administration of the contrast agent.

9. The method of claim 1, wherein the prediction model is an artificial neural network.

10. The method of claim 1, wherein the contrast agent is a hepatobiliary contrast agent, preferably Gd-EOB-DTPA or Gd-BOPTA.

11. A system comprising: a receiving unit, a control and calculation unit, and an output unit, wherein the control and calculation unit being configured to prompt the receiving unit to receive a plurality of MRI images, at least some of the MRI images showing an examination region during a first time span after administering a contrast agent, the control and calculation unit being configured to predict one or more MRI images on the basis of the received MRI images, the one or more predicted MRI images showing the examination region during a second time span, the second time span following the first time span chronologically, and the control and calculation unit being configured to prompt the output unit to display the one or more predicted MRI images, to output them or to store them in a data storage medium.

12. A computer program product comprising a computer program which can be loaded into a memory of a computer system, where it prompts the computer system to execute the following: receiving a plurality of MRI images, at least some of the MRI images showing an examination region during a first time span after administering a contrast agent, feeding the plurality of MRI images to a prediction model, the prediction model having been trained by means of supervised learning to predict, on the basis of MRI images, at least some of which show an examination region during a first time span after administering a contrast agent, one or more MRI images showing the examination region during a second time span, the second time span following the first time span chronologically, generating one or more predicted MRI images showing the examination region during a second time span by means of the prediction model, the second time span following the first time span chronologically, and displaying and/or outputting the one or more predicted MRI images and/or storing the one or more predicted MRI images in a data storage medium.

13. Use of a contrast agent in an MRI method, the MRI method comprising the following: administering the contrast agent, the contrast agent spreading in an examination region, generating a plurality of MRI images of the examination region during a first time span, feeding the generated MRI images to a prediction model, the prediction model having been trained by means of supervised learning to predict, on the basis of MRI images showing an examination region during a first time span, one or more MRI images showing the examination region during a second time span, the second time span following the first time span chronologically, receiving one or more predicted MRI images showing the examination region during a second time span, as output from the prediction model, the second time span following the first time span chronologically, and displaying and/or outputting the one or more predicted MRI images and/or storing the one or more predicted MRI images in a data storage medium.

14. (canceled)

15. A kit comprising a contrast agent as claimed in claim 13, and a computer program product as claimed in claim 12.

16. The use of a contrast agent in the MRI method of claim 13, wherein the contrast agent is preferably a substance or a substance mixture with gadoxetic acid or a gadoxetic acid salt as contrast-enhancing active substance, preferably Gd-EOB-DTPA disodium.

17. The computer program product of claim 12, wherein the first time span is chosen such that it shows the examination region in different phases, wherein the phases comprise a native phase, an arterial phase, a portal-vein phase and a late phase, wherein at least one MRI image is received which shows the examination region in the native phase, and at least one MRI image is received which shows the examination region during the arterial phase, and at least one MRI image is received which shows the examination region in the portal-vein phase, and at least one MRI image is received which shows the examination region in the late phase.

18. The computer program product of claim 12, wherein the plurality of MRI images show a liver or a portion of a liver of a mammal prior to a time point TP0 and during a time span from TP0 to TP1 and/or during a time span from TP1 to TP2 and/or during a time span from TP2 to TP3 and/or during a time span from TP3 to TP4, at time point TP0 the contrast agent being administered intravenously as a bolus and then reaching liver cells via liver arteries and liver veins, at time point TP1 the contrast agent in the liver arteries reaching a maximum concentration, at time point TP2 a signal intensity generated in the liver veins by the contrast agent assuming a value which is the same size as a value of a signal intensity generated in the liver arteries by the contrast agent, at time point TP3 the contrast agent in the liver veins reaching a maximum concentration, at time point TP4 a signal intensity generated in the liver cells by the contrast agent assuming a value which is the same size as a value of a signal intensity generated in the liver veins by the contrast agent.

19. The computer program product of claim 12, wherein the first time span starts within a time span of from one minute to one second before the administration of the contrast agent or with the administration of the contrast agent, and lasts for a time span of from 2 minutes to 15 minutes, preferably 2 minutes to 13 minutes, yet more preferably 3 minutes to 10 minutes, from the administration of the contrast agent.

20. The computer program product of claim 12, wherein the second time span is within a hepatobiliary phase.

21. The computer program product of claim 12, wherein the prediction model is an artificial neural network.

Description

[0121] The disclosure is more particularly elucidated below with reference to figures, without wishing to restrict the disclosure to the features or combinations of features that are shown in the figures, where:

[0122] FIG. 1 shows schematically the temporal profile of the concentrations of contrast agent in the liver arteries (A), the liver veins (V) and the liver cells (P) and has already been described in detail above.

[0123] FIG. 2 shows schematically a preferred embodiment of the system according to the disclosure. The system (10) comprises a receiving unit (11), a control and calculation unit (12) and an output unit (13).

[0124] FIG. 3 shows schematically and exemplarily one embodiment of the method according to the disclosure. The method (100) comprises the steps:

[0125] (110) receiving a plurality of first MRI images, at least some of the first MRI images showing an examination region during a first time span after administering a contrast agent, [0126] (120) feeding the plurality of first MRI images to a prediction model, the prediction model having been trained on the basis of reference MRI images by means of supervised learning to predict, from first reference MRI images showing an examination region during a first time span, one or more second reference MRI images showing the examination region during a second time span, the second time span following the first time span chronologically, [0127] (130) generating one or more predicted MRI images showing the examination region during a second time span by means of the prediction model, the second time span following the first time span chronologically, [0128] (140) displaying and/or outputting the one or more predicted MRI images and/or storing the one or more predicted MRI images in a data storage medium.

[0129] FIG. 4 shows schematically and exemplarily a plurality of MRI images of the liver during the dynamic and the hepatobiliary phase. In FIGS. 4(a), 4(b), 4(c), 4(d), 4(e) and 4(f), the same cross section through the liver at different time points is always depicted. The reference signs entered in FIGS. 4(a), 4(b), 4(d) and 4(f) apply to all of FIGS. 4(a), 4(b), 4(c), 4(d), 4(e) and 4(f); they are each entered only once merely for the sake of clarity.

[0130] FIG. 4(a) shows the cross section through the liver (L) before the intravenous administration of a hepatobiliary contrast agent. At a time point between the time points depicted by FIGS. 4(a) and 4(b), a hepatobiliary contrast agent was administered intravenously as a bolus. This reaches the liver via the liver artery (A) in FIG. 4(b). Accordingly, the liver artery is depicted with signal enhancement (arterial phase). A tumour (T), which is supplied with blood mainly via arteries, likewise stands out from the liver-cell tissue as a lighter (signal-enhanced) region. At the time point depicted in FIG. 4(c), the contrast agent reaches the liver via the veins. In FIG. 4(d), the venous blood vessels (V) stand out from the liver tissue as light (signal-enhanced) regions (venous phase). At the same time, the signal intensity in the healthy liver cells, which are supplied with contrast agent mainly via the veins, continuously rises (FIG. 4(c).fwdarw.4(d).fwdarw.4(e).fwdarw.4(f)). In the hepatobiliary phase depicted in FIG. 4(f), the liver cells (P) are depicted with signal enhancement; the blood vessels and the tumour no longer have contrast agent and are accordingly depicted darkly.

[0131] FIG. 5 shows exemplarily and schematically how three MRI images (1), (2) and (3) showing a liver in a first time span are fed to a prediction model (PM). The prediction model calculates from the three MRI images (1), (2) and (3) an MRI image (4) showing the liver in a second time span. The MRI images (1), (2) and (3) can, for example, show the MRI images shown in FIGS. 4(b), 4(c) and 4(d), The MRI image (4) can, for example, be the MRI image shown in FIG. 4(f).