Imaging system for obtaining quantative perfusion indices

• US 6,542,769 B2
• Filed: 12/18/2000
• Issued: 04/01/2003
• Est. Priority Date: 12/18/2000
• Status: Expired due to Term

• Current Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Original Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Inventors: Sorensen, A. Gregory, Schwamm, Lee H.
• Primary Examiner(s): Walberg, Teresa
• Assistant Examiner(s): Van, Quang T
• Application Number:
  US09/739,194
• Publication Number:
  US 20020111550A1
• Time in Patent Office: 834 Days
• Field of Search: 600/420, 600/407, 600/410, 600/419, 600/310, 600/317, 600/458, 600/481, 600/504, 600/505
• US Class Current: 600/420
• CPC Class Codes: A61B 5/0263 using NMR
• CPC Class Codes: A61B 5/0275 using tracers, e.g. dye dilution
• CPC Class Codes: A61B 5/4064 Evaluating the brain A61B5/031, A61B5/369, A61B5/14553 take precedence

Abstract

A bolus containing optical and MRI contrast agents is administered to a patient for determining quantitative perfusion indices from perfusion weighted magnetic resonance imaging analysis (PWI). The optical contrast agent time-concentration data, which can be obtained non-invasively, is used to define an arterial input function. The MRI contrast agent time concentration can be non-invasively determined using MRI to define a tissue function. An MRI time-signal curve can be determined by deconvolving the arterial and tissue functions. In one embodiment, SVD is used to determine a residue function from which a flow map can be computed.

Claims

1. A method for determining quantitative blood perfusion indices, comprising:

administering a bolus containing an optical contrast agent and an MRI (Magnetic Resonance Imaging) contrast agent;

determining an arterial input function from optical contrast agent concentration samples after the bolus was administered;

determining a tissue function from MRI contrast agent samples in a tissue volume of interest, wherein the contrast optical agent concentration samples and the MRI contrast agent concentration samples are correlated in time;

determining at least one quantitative perfusion index from the arterial input function and the tissue function.

2. The method according to claim 1, wherein the optical contrast agent includes ICG (Indocyanine Green).

3. The method according to claim 1, wherein the MRI contrast agent includes Gd-DTPA (Gadopentetate dimeglumine pentaacetic acid).

4. The method according to claim 1, further including deconvolving an MR signal-time curve from the arterial input function and the tissue function to derive the at least one quantitative perfusion index.

5. The method according to claim 4, further including using SVD (Singular Value Decomposition) to deconvolve the MR signal time curve.

6. The method according to claim 4, further including computing a flow map or a blood volume map.

7. The method according to claim 6, further including determining a residue function from the arterial input function and the tissue function and using the residue function to compute the flow map.

8. The method according to claim 1, further including using optical densitometry to determine the optical contrast agent concentration.

9. The method according to claim 1, further including taking blood samples to determine the optical contrast agent concentration.

10. A method for determining quantitative perfusion indices, comprising:

administering a bolus containing an optical contrast agent and an MRI (Magnetic Resonance Imaging) contrast agent;

determining an arterial input function C_a(t) from the optical contrast agent;

determining a tissue function C_VOI(t) from the MRI contrast agent;

deconvolving an MR signal-time curve from the arterial input function C_a(t) and the tissue function C_VOI(t) based on $C_{\mathrm{VOI}}<br><br>\left(t\right)=F_t<br><br>{\int <br><br>}_0^t<br><br>C_a<br><br>\left(\mathrm{\tau <br><br>}\right)<br><br>R<br><br>\left(t-\mathrm{\tau <br><br>}\right)<br><br><br><br>\mathrm{\tau <br><br>},$

 

where R(t) is a residue function describing the fraction of MRI contrast agent at time t, and F_t represents tissue flow.

11. The method according to claim 10, further including using SVD (Singular Value Decomposition) to deconvolve the MR signal-time curve.

12. The method according to claim 10, wherein the optical contrast agent includes ICG (Indocyanine Green) and the MRI contrast agent includes GDA (gadopentate dimefluminepentaacetic acid).

13. The method according to claim 10, wherein the bolus comprises about 0.125 mg/ml ICG (Indocyanine Green) and about 457 mg mg/ml GDA (gadopentate dimefluminepentaacetic acid).

14. A bolus solution for intravascular injections comprising:

an optical contrast agent including Idocyanine Green; and

an MRI (Magnetic Resonance Imaging) contrast agent including gadopentate dimegluminepentaacetic acid.

15. The solution according to claim 14, wherein the Indocyanine Green has a concentration ranging from about 0.01 to 50% by weight based on the total weight of the composition.

16. The solution according to claim 14, wherein the gadopentate dimegluminepentaacetic acid has a concentration ranging from about 0.001M to about 0.5M.

17. The solution according to claim 14, wherein the optical contrast agent can provide an arterial input function and the MRI (Magnetic Resonance Imaging) contrast agent can provide a tissue function.