Method and system for providing tomographic pictures of a patient by using contrast medium injections

• US 20070066892A1
• Filed: 08/31/2006
• Published: 03/22/2007
• Est. Priority Date: 09/01/2005
• Status: Active Grant

• Current Assignee: Siemens Healthcare GMBH (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Haras, Gabriel, Rauscher-Scheibe, Annabella, Mahnken, Andreas
• Granted Patent: US 7,672,711 B2
• Time in Patent Office: Days
• US Class Current: 600/425
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/481 involving the use of contrast agents
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 6/507 for determination of haemodynamic parameters, e.g. perfusion CT
• CPC Class Codes: G01R 33/5601 involving use of a contrast agent for contrast manipulation, e.g. a paramagnetic, super-paramagnetic, ferromagnetic or hyperpolarised contrast agent

Abstract

A method is disclosed for providing tomographic pictures of a patient with the aid of a tomographic system by using contrast medium injections. The patient is firstly injected with a defined test bolus, while the temporal concentration profile of the contrast medium in at least one body region is determined in at least one scanning plane. The functional parameters of a prediction model that maps or at least approximates the relationship between the profile of a contrast medium injection and the temporal profile of the contrast medium concentration in the body region are determined from the measured profile of the contrast medium concentration in relation to the profile of the test bolus injection. After the specification of a desired contrast in the body region, the profile of a contrast medium injection that is required therefore is automatically calculated in temporal relationship with the scan, and the start of the tomographic scan and the start of the contrast medium injection and the profile thereof are started automatically in a fashion temporally tuned to one another.

Claims

1. A method for a tomographic system, the method comprising:

determining, while a patient is injected with a defined test bolus, a temporal concentration profile of the contrast medium in at least one body region is determined in at least one scanning plane;

determining functional parameters, of a prediction model that at least approximates the relationship between the profile of a contrast medium injection and the temporal profile of the contrast medium concentration in the body region, from the measured profile of the contrast medium concentration in relation to the profile of the test bolus injection;

calculating a profile of a contrast medium injection in temporal relationship with the scan, automatically, in accordance with a desired contrast, in the body region; and

starting, automatically, a start of the tomographic scan and a start of the contrast medium injection and the profile thereof, in a fashion temporally tuned to one another.

2. The method as claimed in claim 1, wherein the functional parameters are stored in a patient-specific fashion.

3. The method as claimed in claim 1, wherein the profile of the test bolus injection and the concentration profile of the contrast medium are stored in a patient-specific fashion with designation of the injection site and the measurement site.

4. The method as claimed in claim 1, wherein the functional parameters determined by the test bolus injection are corrected by use of the contrast data determined during the actual contrast medium injection.

5. The method as claimed in claim 4, wherein the corrected functional parameters are stored in a patient-specific fashion.

6. The method as claimed in claim 1, wherein the contrast profile based on a test bolus injection is determined at a number of body regions in a scanning plane, and the optimum profile of the contrast medium injection for the several body regions is determined.

7. The method as claimed in claim 1, wherein the contrast profile based on a test bolus injection is determined at a number of body regions in different scanning planes, and the optimum contrast medium flow profile is determined for the several body regions.

8. The method as claimed in claim 7, wherein, in the case of a CT examination, the several scanning planes are scanned by use, in each case, of one x-ray tube detector system angularly offset from the other.

9. The method as claimed in claim 6, wherein, in order to calculate the optimum contrast medium flow profile minimum values are defined for the contrast that is to be achieved, and a contrast medium profile is determined that fulfills these minimum values in all body regions considered.

10. The method as claimed in claim 6, wherein in order to calculate the optimum contrast medium flow profile minimum values are defined for the duration of the contrast that is to be achieved, and a contrast medium flow profile is determined that fulfills these temporal minimum values in all the body regions considered.

11. The method as claimed in claim 1, wherein the prediction model includes hemodynamic parameters and the parameters are determined with the aid of at least one of the test bolus injection and the contrast medium injection during the examination scan and are output to the operator.

12. The method as claimed in claim 1, wherein the tomographic system includes at least an x-ray tube and an x-ray detector.

13. The method as claimed in in claim 1, wherein the tomographic system includes at least one PET detector.

14. The method as claimed in in claim 1, wherein the tomographic system includes an NMR system.

15. The method as claimed in in claim 1, wherein the patient-specific data are stored on a chip card dedicated to the patient.

16. The method as claimed in claim 1, wherein an upper limit is prescribed directly or indirectly for at least one of the maximum contrast medium flow and the applied contrast medium quantity that is not exceeded during at least one of the automatic calculation and administration.

17. The method as claimed in claim 16, wherein the upper limit is determined on the basis of patient data that are available.

18. The method as claimed in claim 1, wherein the pulse rate is measured at least one of during the scan and during the contrast medium administration, and the contrast medium supply is stopped automatically and as a matter of priority when a maximum rate is reached.

19. The method as claimed in claim 18, wherein the maximum rate is determined on the basis of patient data that are available.

20. A medical system, comprising:

a recording system with a detector;

a controllable contrast medium injector; and

an arithmetic logic and control unit including stored computer programs that, during operation, control the recording system and the contrast medium injector and calculate tomographic images, the computer programs being adapted, when run during operation, to execute the method of claim 1.

21. The medical system as claimed in claim 20, wherein the contrast medium injector is an independent program controlled unit that includes a memory for holding injection parameters that are passed on by the arithmetic logic and control unit.

22. The medical system as claimed in claim 20, wherein the contrast medium injector includes a control connection to the arithmetic logic and control unit, by use of which the contrast medium injector is controlled.

23. The medical system as claimed in claim 20, wherein at least one of a card reader unit and card writer unit is connected for the purpose of transferring and storing patient-specific data.

24. The method as claimed in claim 1, wherein the functional parameters are stored in a patient-specific fashion, in conjunction with the prediction model used, from the test bolus injection.

25. The method as claimed in claim 2, wherein the profile of the test bolus injection and the concentration profile of the contrast medium are stored in a patient-specific fashion with designation of the injection site and the measurement site.

26. The method as claimed in claim 4, wherein the corrected functional parameters are stored in a patient-specific fashion, in conjunction with the prediction model used.

27. The method as claimed in claim 16, wherein the upper limit is determined on the basis of at least one of the size and weight of the patient.

28. The method as claimed in claim 18, wherein the maximum rate is determined on the basis of at least one of the age, size and weight of the patient.

29. The medical system as claimed in claim 21, wherein at least one of a card reader unit and card writer unit is connected for the purpose of transferring and storing patient-specific data.

30. The medical system as claimed in claim 22, wherein at least one of a card reader unit and card writer unit is connected for the purpose of transferring and storing patient-specific data.