# US 2018/0024216 A1 · Method and system for susceptibility weighted magnetic resonance imaging

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- Number: US 2018/0024216 A1
- Document ID: US20180024216A1
- Status: Published application
- Kind: A1
- Application number: 15/547,557
- Filed: 2016-01-29
- Published: 2018-01-25
- Earliest claimed: 2015-02-03
- Assignees: Koninklijke Philips N.V.
- Applicants: Koninklijke Philips N.V.
- Inventors: GUILLAUME GILBERT; ZHAOLIN CHEN
- Web page: https://patentgrep.com/patent/US20180024216A1

## CPC

- G01R 33/5635: {Angiography, e.g. contrast-enhanced angiography [CE-MRA] or time-of-flight angiography [TOF-MRA]}
- A61B 5/02: Detecting, measuring or recording for evaluating the cardiovascular system, e.g. pulse, heart rate, blood pressure or blood flow
- A61B 5/489: {Blood vessels}
- G01R 33/5608: {Data processing and visualization specially adapted for MR, e.g. for feature analysis and pattern recognition on the basis of measured MR data, segmentation of measured MR data, edge contour detection on the basis of measured MR data, for enhancing measured MR data in terms of signal-to-noise ratio by means of noise filtering or apodization, for enhancing measured MR data in terms of resolution by means for deblurring, windowing, zero filling, or generation of gray-scaled images, colour-coded images or images displaying vectors instead of pixels (image data processing or generation, in general G06T)}
- A61B 2576/02: specially adapted for a particular organ or body part
- G01R 33/5616: {using gradient refocusing, e.g. EPI}
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D)

## Abstract

Method for susceptibility weighted magnetic resonance imaging of vasculature, the method comprising the following steps: —acquiring multi-echo data containing a time-of-flight signal in at least the first echo (S1); —identifying voxels belonging to arteries from the data (S2); and —generating corresponding information on artery presence (S3); The invention further relates to a corresponding system (10) for susceptibility weighted magnetic resonance imaging of vasculature.

## Claims

### Claim 1

A method for susceptibility weighted magnetic resonance imaging of vasculature, the method comprising:
acquiring multi-echo data containing a time-of-flight signal in at least the first echo;
identifying voxels belonging to arteries from the data; and
generating corresponding information on artery presence;
wherein the method further comprises an echo combination step or an echo combination step in combination with a phase masking step; and
wherein said information on artery presence is used to put emphasis on an artery appearance during said echo combination and/or to prevent an inclusion of voxels belonging to arteries in the phase masking step.

### Claim 2 (depends on 1)

The method according to claim 1, wherein an arterial image AI is created and the voxels belonging to arteries are identified in said arterial image.

### Claim 3 (depends on 2)

The method according to claim 2, wherein the arterial image is an image based on first echo data or a combination of the first few echoes, or by calculating a normalized residual of the linear fit of the phase as a function of the echo time.

### Claim 4 (depends on 3)

The method according to claim 3, wherein the arterial image is created using the following approach:
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wherein IEcho1 is the magnitude signal from the first echo or a combination of the first few echoes and |IEcho1| is a low-pass filtered version of the magnitude signal from the first echo or a combination of the first few echoes.

### Claim 5 (depends on 2)

The method according to claim 2, wherein in the echo combination step the magnitude information from the echoes is combined using the following non-linear combination:
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### Claim 6 (depends on 1)

The method according to claim 1, wherein arteries are identified by looking at voxels for which the phase evolution as a function of the echo time is not linear.

### Claim 7 (depends on 2)

The method according to claim 2, wherein the phase masking is applied to the combined magnitude images using the PADRE algorithm.

### Claim 8 (depends on 7)

The method according to claim 7, wherein the Padre mask of the PADRE algorithm is defined as:
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### Claim 9

A computer program product for executing a method comprising:
identifying voxels belonging to arteries from multi-echo data containing a time-of-flight signal in at least the first echo; and
generating corresponding information on artery presence;
wherein the method further comprises an echo combination step or an echo combination step in combination with a phase masking step; and wherein said information on artery presence is used to put emphasis on an artery appearance during said echo combination and/or to prevent an inclusion of voxels belonging to arteries in the phase masking step.

### Claim 10

A system for susceptibility weighted magnetic resonance imaging of vasculature, the system comprising:
a magnetic resonance device comprising:
a pulse generator module configured to generate an excitation signal; and
a data acquirer module, communicatively coupled with the pulse generator module and configured to acquire multi-echo data containing a time-of-flight signal in at least the first echo; and
a post-processor module, communicatively coupled with the magnetic resonance device and configured:
to post-process the data including an echo combination step and/or a phase masking step,
to identify voxels belonging to arteries from the data; and
to generate corresponding information on artery presence, wherein said information on artery presence is used to guide the echo combination and/or phase masking step.

### Claim 11 (depends on 10)

The system according to claim 10, configured to perform the method.

### Claim 12 (depends on 10)

The system according to claim 10, wherein the post-processor module is configured to generate an image of the vasculature from the post-processed data.

### Claim 13 (depends on 10)

The system according to claim 10, further comprising a display generator module, communicatively coupled with the post-processor module and configured to display the image of the vasculature generated from the post-processed data