NMR methods for monitoring blood clot formation
The invention features a method of monitoring a clotting process by measuring a signal characteristic of the NMR relaxation of water in a sample undergoing clotting to produce NMR relaxation data and determining from the NMR relaxation data a magnetic resonance parameter of water in the sample characteristic of the clots being formed.
1. A method of assessing platelet activity comprising:
(i) providing isolated and washed platelets;
(ii) combining said isolated and washed platelets with platelet poor plasma comprising a predetermined minimum level of fibrinogen to form a test sample;
(iii) initiating a clotting process by adding a clotting initiator to said test sample;
(iv) making a series of magnetic resonance relaxation rate measurements of water in said test sample;
(v) transforming said measurements using an algorithm that distinguishes two or more separate water populations within said test sample, wherein each separate water population is characterized by one or more magnetic resonance parameters having one or more values; and
(vi) on the basis of the results of step (v), assessing said platelet activity.
2. The method of claim 1 , wherein said clotting initiator is a combination of RF and AA.
3. The method of claim 1 , further comprising measuring the test sample in the presence of a platelet activator and in the absence of a platelet activator.
4. The method of claim 2 , further comprising measuring the test sample in the presence of a platelet activator and in the absence of a platelet activator.