US5644646A
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Vessel enhancement filtering in magnetic resonance angiography
Assignee: University of Utah Research Foundation Inc
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Filing: 1994-08-05
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Granted: 1997-07-01
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Expires: 2014-08-05
Abstract
Abstract An MRI system includes an MR cylinder, a radio frequency (RF) coil (or antenna), preliminary processing circuitry, and a computer processing system. The RF receiver produces an electrical signal to the preliminary processing circuitry representative of the sensed magnetic field. The preliminary processing circuitry provides a measurement data signal S (which is in the frequency domain) to the computer processing system, which includes a computer processor and a memory. The computer processor stores measurement data signal S as a data matrix M 2 in a larger data matrix M 3 that contains zero values in memory locations surrounding data matrix M 2 . This is referred to as zero-padding. The computer processor performs (zero-padded) Fourier transformation on data matrix M 3 to produce an interpolated image data matrix I D . Interpolated image data matrix I D is processed through enhancement filtering to provide an enhanced image data matrix I E that has improved visibility of vessels. The filtering may be performed by a variety of filters including a max-min SD filter or a cross-section filter.
Inventors
- 👤 Yiping Du
- 👤 Dennis L. Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:54
CPC Classifications
G; G06; G06T; G06T5/00; G06T5/90; G06T5/94; G06T5/20; G06T5/50; G06T2200/00; G06T2200/04; G06T2207/00; G06T2207/10; G06T2207/10072; G06T2207/10088; G06T2207/20; G06T2207/20048; G06T2207/20056; G06T2207/30; G06T2207/30004; G06T2207/30101
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
132 words
A system for enhancing lines in images produced from data that represent a structure of anatomy of a subject and that are produced in a magnetic resonance imaging (MRI) device, the system comprising: a detector that detects signals composed of energy passing through and modified by the structure of anatomy and that produces detection signals reflective of the detected modified energy signals; preprocessing circuitry that receives the detection signals and provides preprocessed signals in response thereto; and processing circuitry that receives the preprocessed signals and performs a transformation thereon to provide an interpolated image data matrix I D and that performs a max-min second difference (SD) line enhancing filtering process on the interpolated image data matrix I D to provide an enhanced image data matrix I E in which lines are enhanced.
Claim 2
Independent Claim
132 words
A system for enhancing lines in images produced from data that represent a structure of anatomy of a subject and that are produced in a magnetic resonance imaging (MRI) device, the system comprising: a detector that detects signals composed of energy passing through and modified by the structure of anatomy and that produces detection signals reflective of the detected modified energy signals; preprocessing circuitry that receives the detection signals and provides preprocessed signals in response thereto; and processing circuitry that receives the preprocessed signals and performs a transformation thereon to provide an interpolated image data matrix I D and that performs a max-min second difference (SD) line enhancing filtering process on the interpolated image data matrix I D to provide an enhanced image data matrix I E in which lines are enhanced.
Claim 3
Dependent Claim
43 words
The system of claim 1 in which the filtering process is of the form SD ij =2f(i)-f(i-1)-f(i+1), where f(i) is the image intensity at point i, and f(i-1) and f(i+1) are the image intensity at the neighboring points of f(i) along direction j.
Claim 4
Dependent Claim
19 words
The system of claim 1 in which the filtering process is applied in thirteen directions around every image point.
Claim 5
Dependent Claim
26 words
The system of claim 1 in which the filtering process determines the difference between the maximum SD and the maximum of zero and the minimum SD.
Claim 6
Dependent Claim
16 words
The system of claim 1 in which the filtering process is performed in a hardware filter.
Claim 7
Dependent Claim
14 words
The system of claim 1 in which the transformation is a zero-padded Fourier transformation.
Claim 8
Dependent Claim
22 words
The system of claim 6 in which intermediate processes are performed on the preprocessed data signals prior to the zero-padded Fourier transformation.
Claim 9
Independent Claim
108 words
A system for enhancing lines in images produced from data that represent a structure of anatomy of a subject, the system comprising: a detector that detects signals composed of energy passing through and modified by the structure of anatomy and that produces detection signals reflective of the detected modified energy signals; preprocessing circuitry that receives the detection signals and provides a preprocessed signals in response thereto; and processing circuitry that receives the preprocessed signals and performs a zero-padded transformation thereon to provide interpolated image data and that performs a line enhancing filtering process on the interpolated image data to provide enhanced image data in which lines are enhanced.
Claim 10
Independent Claim
108 words
A system for enhancing lines in images produced from data that represent a structure of anatomy of a subject, the system comprising: a detector that detects signals composed of energy passing through and modified by the structure of anatomy and that produces detection signals reflective of the detected modified energy signals; preprocessing circuitry that receives the detection signals and provides a preprocessed signals in response thereto; and processing circuitry that receives the preprocessed signals and performs a zero-padded transformation thereon to provide interpolated image data and that performs a line enhancing filtering process on the interpolated image data to provide enhanced image data in which lines are enhanced.
Claim 11
Dependent Claim
19 words
The system of claim 8 in which the line enhancing filtering process is a second difference (SD) filtering process.
Claim 12
Dependent Claim
18 words
The system of claim 9 in which the second difference (SD) filtering process is a non-linear filtering process.
Claim 13
Dependent Claim
19 words
The system of claim 9 in which the second difference (SD) filtering process is a max-min SD filtering process.
Claim 14
Dependent Claim
18 words
The system of claim 9 in which the second difference (SD) filtering process is a cross-section filtering process.
Claim 15
Dependent Claim
49 words
The system of claim 10 in which the non-linear filtering process includes a second difference (SD) operation of the form SD ij =2f(i)-f(i-1)-f(i+1), where f(i) is the image intensity at point i, and f(i-1) and f(i+1) are the image intensity at the neighboring points of f(i) along direction j.
Claim 16
Dependent Claim
28 words
The system of claim 11 in which the max-min SD filtering process determines the difference between the maximum SD and the maximum of zero and the minimum SD.
Claim 17
Dependent Claim
18 words
The system of claim 8 in which the line enhancing filtering process is performed in a hardware filter.
Claim 18
Dependent Claim
110 words
A processing system for enhancing lines in images produced from data that represent a structure of anatomy of a subject and that is detected from signals composed of energy passing through and modified by the structure of anatomy and that is preprocessed to produce preprocessed signals, the computer processing system comprising: a receiving port for receiving the preprocessed signals; memory in which the preprocessed signals are zero-padded; and processing circuitry that performs a transformation on the preprocessed signals to produce transformed image data and that performs a multi-directional second difference (SD) line enhancing filtering process on the transformed image data to provide enhanced image data in which lines are enhanced.
Claim 19
Dependent Claim
110 words
A processing system for enhancing lines in images produced from data that represent a structure of anatomy of a subject and that is detected from signals composed of energy passing through and modified by the structure of anatomy and that is preprocessed to produce preprocessed signals, the computer processing system comprising: a receiving port for receiving the preprocessed signals; memory in which the preprocessed signals are zero-padded; and processing circuitry that performs a transformation on the preprocessed signals to produce transformed image data and that performs a multi-directional second difference (SD) line enhancing filtering process on the transformed image data to provide enhanced image data in which lines are enhanced.
Claim 20
Dependent Claim
20 words
The system of claim 16 in which processing circuitry includes a hardware filter to perform the line enhancing filtering process.
Claim 21
Dependent Claim
13 words
The system of claim 16 in which the transformation is a Fourier transformation.
Claim 22
Independent Claim
132 words
A system for enhancing lines in images produced from data that represent a structure of anatomy of a subject and that are produced in a magnetic resonance imaging (MRI) device, the system comprising: a detector that detects signals composed of energy passing through and modified by the structure of anatomy and that produces detection signals reflective of the detected modified energy signals; preprocessing circuitry that receives the detection signals and provides preprocessed signals in response thereto; and processing circuitry that receives the preprocessed signals and performs a transformation thereon to provide an interpolated image data matrix I D and that performs a multi-directional second difference (SD) line enhancing filtering process on the interpolated image data matrix I D to provide an enhanced image data matrix I E in which lines are enhanced.
Claim 23
Independent Claim
132 words
A system for enhancing lines in images produced from data that represent a structure of anatomy of a subject and that are produced in a magnetic resonance imaging (MRI) device, the system comprising: a detector that detects signals composed of energy passing through and modified by the structure of anatomy and that produces detection signals reflective of the detected modified energy signals; preprocessing circuitry that receives the detection signals and provides preprocessed signals in response thereto; and processing circuitry that receives the preprocessed signals and performs a transformation thereon to provide an interpolated image data matrix I D and that performs a multi-directional second difference (SD) line enhancing filtering process on the interpolated image data matrix I D to provide an enhanced image data matrix I E in which lines are enhanced.
Claim 24
Dependent Claim
16 words
The system of claim 19 in which the filtering process is a max-min SD filtering process.
Claim 25
Dependent Claim
15 words
The system of claim 19 in which the filtering process is a cross-section filtering process.
Claim 26
Dependent Claim
14 words
The system of claim 19 in which the transformation is a zero-padded Fourier transformation.
Claim 27
Dependent Claim
44 words
The system of claim 19 in which the filtering process is of the form SD ij =2f(i) -f(i-1)-f(i+1), where f(i) is the image intensity at point i, and f(i-1) and f(i+1) are the image intensity at the neighboring points of f(i) along direction j.
Claim 28
Independent Claim
131 words
A system for enhancing lines in images produced from data that represent a structure of anatomy of a subject and that are produced in a magnetic resonance imaging (MRI) device, the system comprising: a detector that detects signals composed of energy passing through and modified by the structure of anatomy and that produces detection signals reflective of the detected modified energy signals; preprocessing circuitry that receives the detection signals and provides preprocessed signals in response thereto; and a computer processor system that receives the preprocessed signals and performs a transformation thereon to provide an interpolated image data matrix I D and that performs a cross-sectional line enhancing filtering process on the interpolated image data matrix I D to provide an enhanced image data matrix I E in which lines are enhanced.
Claim 29
Independent Claim
131 words
A system for enhancing lines in images produced from data that represent a structure of anatomy of a subject and that are produced in a magnetic resonance imaging (MRI) device, the system comprising: a detector that detects signals composed of energy passing through and modified by the structure of anatomy and that produces detection signals reflective of the detected modified energy signals; preprocessing circuitry that receives the detection signals and provides preprocessed signals in response thereto; and a computer processor system that receives the preprocessed signals and performs a transformation thereon to provide an interpolated image data matrix I D and that performs a cross-sectional line enhancing filtering process on the interpolated image data matrix I D to provide an enhanced image data matrix I E in which lines are enhanced.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-06-30 | 2000-12-30 | 2001-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-06-30 | 2004-12-30 | 2005-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-06-30 | 2008-12-30 | 2009-07-01 | $7700.00 | Window Closed / Lapsed |