Method for determining the effectiveness of a medical therapy by analysis of collateral vessels

• US 7,195,598 B2
• Filed: 05/23/2003
• Issued: 03/27/2007
• Est. Priority Date: 05/23/2003
• Status: Expired due to Fees

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Kuth, Rainer, Fuchs, Friedrich
• Primary Examiner(s): Nasser; Robert L.
• Application Number:
  US10/444,280
• Publication Number:
  US 20040236234A1
• Time in Patent Office: 1,404 Days
• Field of Search: 600/500
• US Class Current: 600/504
• CPC Class Codes: A61B 5/0263 using NMR
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00

Abstract

In a method for determining the effectiveness of a therapy for alleviating a constriction in a blood vessel, the functioning of collateral vessels naturally formed at the constriction is analyzed. The analysis takes place by making a blood flow measurement at the vessel in which the constriction is present, or at a complementary vessel, with the patient experiencing two different stress conditions. The flow measurement can ensue by magnetic resonance or using ultrasound. Comparison of the stress-dependent blood flow to a reference is then undertaken to determine whether the collateral vessels are functioning effectively, and thus whether the treatment for alleviating the constriction is effective.

Claims

1. A method for analyzing functioning of a collateral vessel formed at a constriction in a blood vessel of a living subject, comprising the steps of:

determining blood flow in said collateral vessel of said living subject at a measuring location selected from the group consisting of in the proximity of said constriction and in a complementary blood vessel to the blood vessel containing the constriction, with said living subject in at least two different stress conditions; and

evaluating said functioning of said collateral vessel dependent on said blood flow relative to stress.

2. A method as claimed in claim 1 comprising determining said functioning of said collateral vessel by a comparison of said blood flow relative to stress with respect to a reference value.

3. A method as claimed in claim 2 comprising obtaining said reference value by making a blood flow measurement at a blood vessel disposed at an opposite side of said living subject from said blood vessel containing said constriction.

4. A method as claimed in claim 2 comprising obtaining said reference value from a table of stress-dependent blood flow values on a group of subjects comparable to said living subject.

5. A method as claimed in claim 1 comprising inducing said stress conditions by administering medication to said living subject.

6. A method as claimed in claim 1 comprising inducing said stress conditions by said living subject undergoing physical activity.

7. A method as claimed in claim 6 wherein at least one of said stress conditions is a static stress condition.

8. A method as claimed in claim 7 wherein another of said stress conditions is a dynamic stress condition.

9. A method as claimed in claim 1 comprising measuring said blood flow by magnetic resonance.

10. A method as claimed in claim 1 comprising measuring said blood flow by an ultrasound measurement.

11. A method as claimed in claim 1 comprising the additional step of evaluating effectiveness of a treatment for alleviating said constriction, administered to said living subject, from said criterion for the functioning of said collateral vessel.