Method to measure the molecular diffusion and/or perfusion parameters of live tissue

• US 4,809,701 A
• Filed: 09/23/1987
• Issued: 03/07/1989
• Est. Priority Date: 09/26/1986
• Status: Expired due to Term

• Current Assignee: Thomson Cgr
• Original Assignee: Thomson Cgr
• Inventors: Le Bihan, Denis, Breton, Eric
• Primary Examiner(s): SMITH, RUTH S
• Application Number:
  US07/100,261
• Time in Patent Office: 531 Days
• Field of Search: 128/653, 128/696, 324/307, 324/309, 324/306
• US Class Current: 600/413
• CPC Class Codes: G01R 33/56341 Diffusion imaging
• CPC Class Codes: G01R 33/5673 Gating or triggering based on a physiological signal other than an MR signal, e.g. ECG gating or motion monitoring using optical systems for monitoring the motion of a fiducial marker

Abstract

By synchronizing the radio-frequency excitations of a nuclear magnetic resonance experiment with the heart beat of a patient, notable improvement is obtained in the measurement of the molecular diffusion parameters of the tissues studied. In particular, good images of the brain are obtained in this way: the parameter represented is the molecular diffusion constant.

Claims

1. A method to measure the molecular diffusion parameters of a live and resting tissue of a patient using an NMR experiment, comprising at least one series of radio-frequency excitation sequences of said tissue, each sequence being followed by measurements of a NMR signal resulting from said excitations, said NMR signals being then processed for giving said molecular diffusion parameters, wherein the excitations are synchronized with the cardiac rhythm of the patient.

2. A method according to the claim 1, wherein the measurement comprises an imaging of the parameters.

3. A method according to the claim 1, wherein one of the parameters is the molecular diffusion constant.

4. A method according to the claim 1, wherein the tissue is the tissue of the patient'"'"'s brain.

5. A method according to the claim 1, wherein the excitations are synchronized with selected instants of the patient'"'"'s heart rhythm.

6. A method according to the claim 1 wherein, at the end of a first and second series of excitation sequences, a first image and second image are acquired, a characteristic of the experiment being modified during the second series of the excitation sequence, the molecular diffusion parameters being deduced in a third image of point-to-point comparisons of the first two images.

7. A method to measure the perfusion parameters of a live and resting tissue of a patient using an NMR experiment, comprising at least one series of radio-frequency excitation sequences of said tissue, each sequence being followed by measurements of a NMR signal resulting from said excitations, said NMR signals being then processed for giving said perfusion parameters, wherein the excitations are synchronized with the heart beat of the patient.

8. A method to measure the molecular diffusion and perfusion parameters of a live and resting tissue of a patient using an NMR experiment, comprising at least one series of radio-frequency excitation sequences of said tissue, each sequence being followed by measurements of a NMR signal resulting from said excitations, said NMR signals being then processed for giving said parameters, wherein the excitations are synchronized with the heart beat of the patient.