VESSEL SIZE IMAGING FOR ANTIANGIOGENIC THERAPY

• US 20080294035A1
• Filed: 05/21/2008
• Published: 11/27/2008
• Est. Priority Date: 05/23/2007
• Status: Active Grant

• Current Assignee: Siemens Healthcare GMBH (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Schmidt, Sebastian, Hengerer, Arne, Strecker, Ralph, Kiessling, Fabian, Zwick, Stefan
• Granted Patent: US 8,195,275 B2
• Time in Patent Office: Days
• US Class Current: 600/420
• CPC Class Codes: A61B 5/0515 Magnetic particle imaging
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/4833 Assessment of subject's compliance to treatment
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes

Abstract

A system and method of evaluating the effectiveness of antiangionetic therapy is described. A patient or test animal is treated with an antiangionetic substance. Magnetic resonance imaging data is obtained prior to and subsequent to the treatment. The parameters of the imaging process are configured so that, by administering a intravascular contrast agent, the relative size of the microvascular and the total vascular volumes in a region of interest may be obtained, so as to form a vascular size index. The value of the vascular size index and other pharmacokinetic data obtained by the administration of a diffusible contrast agent are used to assess the efficacy of the treatment or the antiangionetic substance being studied.

Claims

1. A method of assessing angiographic therapy, the method comprising:

placing a subject in a magnetic resonance imaging (MRI) device;

administering a blood pool contrast agent;

obtaining a MRI image sequence data set; and

determining a vessel size index value.

2. The method of claim 1, wherein the volume of blood pool contrast agent administered is proportional to the subject body weight.

3. The method of claim 1, wherein a dynamic contrast enhanced (DCE) MRI data set is obtained prior to the step of obtaining the MRI image sequence data set.

4. The method of claim 1, wherein the blood pool contrast agent comprises nanoparticles.

5. The method of claim 1, wherein the blood pool contrast agent comprises macromolecules.

6. The method of claim 3, further comprising the administration of a diffusible contrast agent when obtaining the DCE MRI data set.

7. The method of claim 3, wherein evaluation of the DCE MRI data set comprises the application of pharmacokinetic models to the data set.

8. The method of claim 1, wherein the vessel size index value is parametric in the ratio of the change in the T₂* weighted image relaxation rate to the change in the T₂ spin echo image relaxation rate.

9. The method of claim 1, wherein during acquisition of the data set transversal relaxation rates R₂ and R₂* are measured before and after contrast agent administration.

10. The method of claim 1, wherein the vessel size value obtained before and after therapy with a therapeutic agent is used to assess the relative effectiveness of the therapeutic agent.

11. The method of claim 3, wherein the DCI MRI and the vessel size index value are used to evaluate the effectiveness of the therapy.

12. A system for treating a patient, comprising:

a magnetic resonance imaging (MRI) device; and

a catheter;

wherein the catheter is used to administer an intravascular contrast agent, and the magnetic resonance imaging device obtains images suitable for performing vascular size imaging analysis.

13. The system of claim 12, further comprising a computer configured to perform vascular size imaging, the vascular size imaging comprising measuring a first parameter proportional to a volume of the microvascular network in a region of interest and a second parameter proportional to a volume of all of the blood vessels in the region of interest.

14. The system of claim 13, where an effectiveness of the treatment of the patient is based on the ratio of the first parameter to the second parameter.

15. A computer system comprising:

a control unit for controlling a magnetic resonance imaging device and obtaining image data sets;

a database having a plurality of records, the records containing magnetic resonance image data sets; and

a user interface allowing evaluation of image data sets stored in the database,

wherein at least some of the magnetic imaging data sets are obtained using an intravascular contrast agent, the evaluation resulting in a vessel size index value.

16. The computer system of claim 15, wherein the database is accessible over a network.

17. The computer system of claim 16, wherein the magnetic imaging data sets are compatible with DIOCM (digital communications in medicine).

18. A computer program product comprising

a computer-readable medium having computer-readable program code embodied thereon, the program code executable on a computer to process image data by:

applying pharmacokinetic models to a first type of image data so as to calculate parameters with relevant physiological information;

calculating a vessel size index value characterizing a second type of image data; and

presenting the physiological information and the vessel size index value at a user interface.

19. The computer program product of claim 18, further comprising software for causing the computer to:

associate a plurality of records of image data so as to relate the image data with a project or a patient; and

accept data input at a data interface to control an evaluation of the image data.