EP0543468A1
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Magnetic resonance imaging method
Assignee: Koninklijke Philips NV
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Filing: 1992-11-23
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Granted: —
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Expires: 2012-11-23
Abstract
Abstract A magnetic resonance imaging method is proposed for the following of a dynamic process in a body (5), such as perfusion in the brain by means of a contrast agent such as Gd-DTPA, or the effects of a physical stimulus. The dynamic process is followed by way of a multiple-slice MR measurement through, for example, 10 slices. In accordance with the invention, before or after the injection of the contrast agent, high-resolution reference images of the slices are formed, the same slices being measured with a lower resolution during the perfusion of the contrast agent. Substitution of the low-resolution data in data matrices containing high-resolution data produces, after Fourier transformation, images of the slices in which the measured changes in image intensities due to the contrast medium are reproduced in the high-resolution images.
Inventors
- 👤 Hans Hermanus c/o Int. Octrooibur. B.V. Tuithof
- 👤 Johannes J. c/o Int. Octrooibur. B.V. Van Vaals
- 👤 William Thomas c/o Int. Octrooibur. B.V. Dixon
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 17:54
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01R33/48; G01R33/54; G01R33/56; G01R33/563; G01R33/28; G01R33/281; G01R33/561; G01R33/5615; G01R33/5617; G01R33/5619; G01R33/56308
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
173 words
A magnetic resonance imaging method for following a dynamic process in a body, in which method a local modification of magnetic resonance properties is induced in the body for the selective variation of magnetic resonance signals to be generated in the body, magnetic resonance signals being acquired during, or during and after, the realization of the modification by way of a first signal acquisition method in order to form a series of magnetic resonance images of the body enabling the dynamic process to be followed, characterized in that the first signal acquisition method is a low-resolution method, and in that at an appropriate instant, using a second, high-resolution signal acquisition method, magnetic resonance signals are acquired from the body in order to form at least one reference image of the body, signal samples of the magnetic resonance signals acquired by means of the low-resolution method being supplemented, prior to the formation of the series of magnetic resonance images by signal samples of the magnetic resonance signals acquired by means of the high-resolution method.
Claim 2
Dependent Claim
30 words
A magnetic resonance imaging method as claimed in Claim 1, characterized in that an enhancement agent is applied in order to realise the local modification of the magnetic resonance properties.
Claim 3
Dependent Claim
30 words
A magnetic resonance imaging method as claimed in Claim 1, characterized in that a physical stimulus is applied in order to realise the local modification of the magnetic resonance properties.
Claim 4
Dependent Claim
46 words
A magnetic resonance imaging method as claimed in Claim 1, 2 or 3, characterized in that the magnetic resonance signals are acquired by means of the second, high-resolution signal acquisition method after acquisition of the magnetic resonance signals by means of the first signal acquisition method.
Claim 5
Dependent Claim
52 words
A magnetic resonance imaging method as claimed in Claim 1, 2, 3 or 4, characterized in that the reference images are images of slices of a volume part of the body in which the dynamic process takes place, the series of magnetic resonance images comprising a number of images of the slices.
Claim 6
Dependent Claim
72 words
A magnetic resonance imaging method as claimed in Claim 1, 2, 3, 4 or 5, characterized in that the first and the second signal acquisition method are Fourier methods comprising a high-frequency excitation pulse, a phase-encoding gradient and a read-out gradient, the signal samples obtained by means of the high-resolution method being stored in data matrices, the signal samples obtained by means of the low-resolution method being substituted in the data matrices.
Claim 7
Dependent Claim
17 words
A magnetic resonance imaging method as claimed in Claim 6, characterized in that the substitution is symmetrical.
Claim 8
Dependent Claim
17 words
A magnetic resonance imaging method as claimed in Claim 6, characterized in that the substitution is asymmetrical.
Claim 9
Dependent Claim
28 words
A magnetic resonance imaging method as claimed in Claim 1, 2, 3, 4 or 5, characterized in that the first and second signal acquisition methods are echoplanar methods.
Claim 10
Dependent Claim
61 words
A magnetic resonance imaging method as claimed in Claim 1, 2, 3, 4 or 5, characterized in that per reference image the high-resolution method comprises a number of gradient-echo sequences preceded by inversion pulses, signal samples thereof filling data matrices in a mosaic-like manner, the low-resolution method comprising similar sequences, signal samples thereof partly substituting high-resolution data in the data matrices.
Claim 11
Dependent Claim
50 words
A magnetic resonance imaging method as claimed in any one of the preceding Claims, characterized in that the dynamic process is perfusion of an enhancement agent in the brain or the heart in the body or the taking up of an enhancement agent in the mammary tumors in the body.
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