US5412702A
Expired / Lapsed
US
⏱️ 0.0 years remaining
X-ray computerized tomographic imaging method and imaging system capable of forming scanogram data from helically scanned data
Assignee: Toshiba Corp
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Filing: 1992-09-11
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Granted: 1995-05-02
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Expires: 2012-09-11
Abstract
Abstract In an X-ray CT (computerized tomographic) imaging method, scano data is produced from X-ray projection image data about a helically-scanned biological body under medical examination. The X-ray projection image data are acquired only at a predetermined projection angle such as 0° during a helical scanning operation. Accordingly, no X-ray projection to acquire the scano data is required to reduce X-ray dose given to the biological body. The X-ray CT imaging method comprises the steps of: scanning a biological body under medical examination in a helical scanning mode, while relatively rotating an X-ray tube and an X-ray detector around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body; selecting only X-ray projection image data acquired at a predetermined projection angle from the entire X-ray projection image data obtained at the helical-scanning step; processing said selected X-ray projection image data to produce a scanogram of said helically-scanned biological body; and reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data, whereby both of said scanogram and said X-ray CT image are substantially simultaneously displayed.
Inventors
- 👤 Shingo Sata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 23:12
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/02; A61B6/03; A61B6/032; A61B6/027
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
130 words
An X-ray CT (computerized tomographic) imaging method comprising the steps of: scanning a biological body under medical examination in a helical scanning mode, while relatively rotating an X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body; selecting only X-ray projection image data acquired by an X-ray detector at a predetermined projection angle from the entire X-ray projection image data obtained at the helical-scanning step; processing said selected X-ray projection image data to produce a scanogram of said helically-scanned biological body; and reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data, whereby both of said scanogram and said X-ray CT image are substantially simultaneously displayed.
Claim 2
Dependent Claim
130 words
An X-ray CT (computerized tomographic) imaging method comprising the steps of: scanning a biological body under medical examination in a helical scanning mode, while relatively rotating an X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body; selecting only X-ray projection image data acquired by an X-ray detector at a predetermined projection angle from the entire X-ray projection image data obtained at the helical-scanning step; processing said selected X-ray projection image data to produce a scanogram of said helically-scanned biological body; and reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data, whereby both of said scanogram and said X-ray CT image are substantially simultaneously displayed.
Claim 3
Dependent Claim
44 words
An X-ray CT imaging method as claimed in claim 1, wherein said predetermined projection angle is selected from any one of 0°, 90° and 180° with respect to a base line located within a plane perpendicular to said longitudinal axis of the biological body.
Claim 4
Dependent Claim
101 words
An X-ray CT imaging method as claimed in claim 1, wherein said processing step includes the steps of: executing a curved plane/flat plane transformation with regard to said selected X-ray projection image data acquired at said predetermined projection angle to obtain plane-transformed X-ray projection image data; executing a highpass filtering operation with respect to the plane-transformed X-ray projection image data to obtain filtered X-ray projection image data; and executing a density conversion with regard to the filtered X-ray projection image data to obtain density-converted X-ray projection image data, whereby said scanogram is produced based upon the density-converted X-ray projection image data.
Claim 5
Dependent Claim
67 words
An X-ray CT imaging method as claimed in claim 3, wherein said processing step further includes the step of: rearranging the plane-transformed X-ray projection image data when being acquired at a second projection angle opposite to said predetermined projection angle, whereby the rearranged X-ray projection image data acquired at said second projection angle correspond to the plane-transformed X-ray projection image data acquired at said predetermined projection angle.
Claim 6
Dependent Claim
136 words
An X-ray CT (computerized tomographic) imaging method comprising the steps of: scanning a biological body under medical examination in a helical scanning mode, while relatively rotating an X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body; selecting only X-ray projection image data acquired by an X-ray detector at first and second projection angles from the entire X-ray projection image data obtained at the helical-scanning step; processing said selected X-ray projection image data to produce first and second scanograms of said helically-scanned biological body; and reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data, whereby both of said first and second scanograms and said X-ray CT image are substantially simultaneously displayed.
Claim 7
Dependent Claim
136 words
An X-ray CT (computerized tomographic) imaging method comprising the steps of: scanning a biological body under medical examination in a helical scanning mode, while relatively rotating an X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body; selecting only X-ray projection image data acquired by an X-ray detector at first and second projection angles from the entire X-ray projection image data obtained at the helical-scanning step; processing said selected X-ray projection image data to produce first and second scanograms of said helically-scanned biological body; and reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data, whereby both of said first and second scanograms and said X-ray CT image are substantially simultaneously displayed.
Claim 8
Dependent Claim
60 words
An X-ray CT imaging method as claimed in claim 5, wherein said first and second projection angles are 0° and 90° with respect to a base line located within a plane perpendicular to said longitudinal axis of the biological body, whereby a top-viewed scanogram is obtained as said first scanogram and a side-viewed scanogram is obtained as said second scanogram.
Claim 9
Dependent Claim
201 words
An X-ray CT (computerized tomographic) imaging method comprising the steps of: scanning a first portion of a biological body under medical examination by continuously projecting an X-ray beam to the first portion in a helical scanning mode, while relatively rotating an X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire first X-ray projection image data about the helically-scanned first portion of the biological body by means of an X-ray detector; scanning a second portion of said biological body under medical examination by intermittently projecting an X-ray beam to the second portion of the biological body at a predetermined projection angle from the X-ray tube, to acquire second X-ray projection image data about the scanned second portion of the biological body; processing said second X-ray projection image data to produce a scanogram of said scanned second portion of the biological body by selecting only X-ray projection image data acquired at a predetermined projection angle from the entire X-ray projection image data; and reconstructing an X-ray CT image of said helically-scanned biological body based upon said first X-ray projection image data, whereby both of said scanogram and said X-ray CT image are substantially simultaneously displayed.
Claim 10
Dependent Claim
201 words
An X-ray CT (computerized tomographic) imaging method comprising the steps of: scanning a first portion of a biological body under medical examination by continuously projecting an X-ray beam to the first portion in a helical scanning mode, while relatively rotating an X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire first X-ray projection image data about the helically-scanned first portion of the biological body by means of an X-ray detector; scanning a second portion of said biological body under medical examination by intermittently projecting an X-ray beam to the second portion of the biological body at a predetermined projection angle from the X-ray tube, to acquire second X-ray projection image data about the scanned second portion of the biological body; processing said second X-ray projection image data to produce a scanogram of said scanned second portion of the biological body by selecting only X-ray projection image data acquired at a predetermined projection angle from the entire X-ray projection image data; and reconstructing an X-ray CT image of said helically-scanned biological body based upon said first X-ray projection image data, whereby both of said scanogram and said X-ray CT image are substantially simultaneously displayed.
Claim 11
Dependent Claim
44 words
An X-ray CT imaging method as claimed in claim 7, wherein said predetermined projection angle is selected from any one of 0°, 90° and 180° with respect to a base line located within a plane perpendicular to said longitudinal axis of the biological body.
Claim 12
Dependent Claim
46 words
An X-ray CT imaging method as claimed in claim 7, wherein said predetermined projection angle is selected from any two combined angles of 0°, 90° and 180° with respect to a base line located within a plane perpendicular to said longitudinal axis of the biological body.
Claim 13
Dependent Claim
101 words
An X-ray CT imaging method as claimed in claim 9, wherein said processing step includes the steps of: executing a curved plane/flat plane transformation with regard to said selected X-ray projection image data acquired at said predetermined projection angle to obtain plane-transformed X-ray projection image data; executing a highpass filtering operation with respect to the plane-transformed X-ray projection image data to obtain filtered X-ray projection image data; and executing a density conversion with regard to the filtered X-ray projection image data to obtain density-converted X-ray projection image data, whereby said scanogram is produced based upon the density-converted X-ray projection image data.
Claim 14
Dependent Claim
67 words
An X-ray CT imaging method as claimed in claim 10, wherein said processing step further includes the step of: rearranging the plane-transformed X-ray projection image data when being acquired at a second projection angle opposite to said predetermined projection angle, whereby the rearranged X-ray projection image data acquired at said second projection angle correspond to the plane-transformed X-ray projection image data acquired at said predetermined projection angle.
Claim 15
Dependent Claim
166 words
An X-ray CT (computerized tomographic) imaging system comprising: scanning means including an X-ray source and an X-ray detector, for scanning a biological body under medical examination in a helical scanning mode, while relatively rotating said X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body; scano data processing means for selecting only X-ray projection image data acquired by said X-ray detector at a predetermined projection angle from the entire X-ray projection image data, and for processing said selected X-ray projection image data to produce a scanogram of said helically-scanned biological body by selecting only X-ray projection image data acquired at a predetermined projection angle from the entire X-ray projection image data; CT image reconstructing means for reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data; and display means for substantially simultaneously displaying both of said scanogram and said X-ray CT image.
Claim 16
Dependent Claim
166 words
An X-ray CT (computerized tomographic) imaging system comprising: scanning means including an X-ray source and an X-ray detector, for scanning a biological body under medical examination in a helical scanning mode, while relatively rotating said X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body; scano data processing means for selecting only X-ray projection image data acquired by said X-ray detector at a predetermined projection angle from the entire X-ray projection image data, and for processing said selected X-ray projection image data to produce a scanogram of said helically-scanned biological body by selecting only X-ray projection image data acquired at a predetermined projection angle from the entire X-ray projection image data; CT image reconstructing means for reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data; and display means for substantially simultaneously displaying both of said scanogram and said X-ray CT image.
Claim 17
Dependent Claim
106 words
An X-ray CT imaging system as claimed in claim 12, wherein said scano data processing means includes: means for executing a curved plane/flat plane transformation with regard to said selected X-ray projection image data acquired at said predetermined projection angle to obtain plane-transformed X-ray projection image data; means for executing a highpass filtering operation with respect to the plane-transformed X-ray projection image data to obtain filtered X-ray projection image data; and means for executing a density conversion with regard to the filtered X-ray projection image data to obtain density-converted X-ray projection image data, whereby said scanogram is produced based upon the density-converted X-ray projection image data.
Claim 18
Dependent Claim
68 words
An X-ray CT imaging system as claimed in claim 13, wherein said scano data processing means further includes: means for rearranging the plane-transformed X-ray projection image data when being acquired at a second projection angle opposite to said predetermined projection angle, whereby the rearranged X-ray projection image data acquired at said second projection angle correspond to the plane-transformed X-ray projection image data acquired at said predetermined projection angle.
Claim 19
Dependent Claim
71 words
An X-ray CT imaging system as claimed in claim 12, further comprising: preprocessing means for preprocessing said X-ray projection image data obtained from said scanning means to produce the preprocessed X-ray projection image data to be supplied to both of said scano data processing means and said CT image reconstructing means; and synthesizing means for synthesizing said scanogram and said X-ray CT image to be substantially displayed on said display means.
Claim 20
Dependent Claim
44 words
An X-ray CT imaging system as claimed in claim 12, wherein said predetermined projection angle is selected from any one of 0°, 90° and 180° with respect to a base line located within a plane perpendicular to said longitudinal axis of the biological body.
Claim 21
Dependent Claim
157 words
An X-ray CT imaging system comprising: scanning means including an X-ray source and an X-ray detector, for scanning a biological body under medical examination in a helical scanning mode, while relatively rotating said X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body by means of said X-ray detector; scano data processing means for selecting only X-ray projection image data acquired at first and second projection angles from the entire X-ray projection image data obtained from said scanning means, and for processing said selected X-ray projection image data to produce first and second scanograms of said helically-scanned biological body; CT image reconstructing means for reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data; and display means for substantially simultaneously displaying both of said first and second scanograms and said X-ray CT image.
Claim 22
Dependent Claim
157 words
An X-ray CT imaging system comprising: scanning means including an X-ray source and an X-ray detector, for scanning a biological body under medical examination in a helical scanning mode, while relatively rotating said X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire X-ray projection image data about the helically-scanned biological body by means of said X-ray detector; scano data processing means for selecting only X-ray projection image data acquired at first and second projection angles from the entire X-ray projection image data obtained from said scanning means, and for processing said selected X-ray projection image data to produce first and second scanograms of said helically-scanned biological body; CT image reconstructing means for reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data; and display means for substantially simultaneously displaying both of said first and second scanograms and said X-ray CT image.
Claim 23
Dependent Claim
64 words
An X-ray CT imaging system as claimed in claim 17, wherein said first and second projection angles are 0° and 90° with respect to a base line located within a plane perpendicular to said longitudinal axis of the biological body, whereby a top-viewed scanogram is displayed as said first scanogram and a side-viewed scanogram is displayed as said second scanogram on said display means.
Claim 24
Dependent Claim
106 words
An X-ray CT imaging system as claimed in claim 17, wherein said scano data processing means includes: means for executing a curved plane/flat plane transformation with regard to said selected X-ray projection image data acquired at said predetermined projection angle to obtain plane-transformed X-ray projection image data; means for executing a highpass filtering operation with respect to the plane-transformed X-ray projection image data to obtain filtered X-ray projection image data; and means for executing a density conversion with regard to the filtered X-ray projection image data to obtain density-converted X-ray projection image data, whereby said scanogram is produced based upon the density-converted X-ray projection image data.
Claim 25
Dependent Claim
68 words
An X-ray CT imaging system as claimed in claim 19, wherein said scano data processing means further includes: means for rearranging the plane-transformed X-ray projection image data when being acquired at a second projection angle opposite to said predetermined projection angle, whereby the rearranged X-ray projection image data acquired at said second projection angle correspond to the plane-transformed X-ray projection image data acquired at said predetermined projection angle.
Claim 26
Dependent Claim
71 words
An X-ray CT imaging system as claimed in claim 17, further comprising: preprocessing means for preprocessing said X-ray projection image data obtained from said scanning means to produce the preprocessed X-ray projection image data to be supplied to both of said scano data processing means and said CT image reconstructing means; and synthesizing means for synthesizing said scanogram and said X-ray CT image to be substantially displayed on said display means.
Claim 27
Dependent Claim
202 words
An X-ray CT imaging system comprising: scanning means including an X-ray source and an X-ray detector, for continuously scanning a first portion of a biological body under medical examination in a helical scanning mode, while relatively rotating said X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire first X-ray projection image data about the helically-scanned first portion of the biological body by said X-ray detector, and also for scanning a second portion of said biological body by intermittently projecting an X-ray beam of said X-ray source to the second portion of the biological body, to acquire second X-ray projection image data about the scanned second portion of the biological body; scano data processing means for processing said second X-ray projection image data to produce a scanogram of said scanned second portion of the biological body by selecting only X-ray projection image data acquired at a predetermined projection angle from the entire X-ray projection image data; CT image reconstructing means for reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data; and display means for substantially simultaneously displaying both of said scanogram and said X-ray CT image.
Claim 28
Dependent Claim
202 words
An X-ray CT imaging system comprising: scanning means including an X-ray source and an X-ray detector, for continuously scanning a first portion of a biological body under medical examination in a helical scanning mode, while relatively rotating said X-ray source around the biological body translated along a longitudinal axis of the biological body, to acquire first X-ray projection image data about the helically-scanned first portion of the biological body by said X-ray detector, and also for scanning a second portion of said biological body by intermittently projecting an X-ray beam of said X-ray source to the second portion of the biological body, to acquire second X-ray projection image data about the scanned second portion of the biological body; scano data processing means for processing said second X-ray projection image data to produce a scanogram of said scanned second portion of the biological body by selecting only X-ray projection image data acquired at a predetermined projection angle from the entire X-ray projection image data; CT image reconstructing means for reconstructing an X-ray CT image of said helically-scanned biological body based upon said entire X-ray projection image data; and display means for substantially simultaneously displaying both of said scanogram and said X-ray CT image.
Claim 29
Dependent Claim
44 words
An X-ray CT imaging system as claimed in claim 22, wherein said predetermined projection angle is selected from any one of 0°, 90° and 180° with respect to a base line located within a plane perpendicular to said longitudinal axis of the biological body.
Claim 30
Dependent Claim
106 words
An X-ray CT imaging system as claimed in claim 22, wherein said scano data processing means includes: means for executing a curved plane/flat plane transformation with regard to said selected X-ray projection image data acquired at said predetermined projection angle to obtain plane-transformed X-ray projection image data; means for executing a highpass filtering operation with respect to the plane-transformed X-ray projection image data to obtain filtered X-ray projection image data; and means for executing a density conversion with regard to the filtered X-ray projection image data to obtain density-converted X-ray projection image data, whereby said scanogram is produced based upon the density-converted X-ray projection image data.
Claim 31
Dependent Claim
68 words
An X-ray CT imaging system as claimed in claim 24, wherein said scano data processing means further includes: means for rearranging the plane-transformed X-ray projection image data when being acquired at a second projection angle opposite to said predetermined projection angle, whereby the rearranged X-ray projection image data acquired at said second projection angle correspond to the plane-transformed X-ray projection image data acquired at said predetermined projection angle.
Claim 32
Dependent Claim
71 words
An X-ray CT imaging system as claimed in claim 22, further comprising: preprocessing means for preprocessing said X-ray projection image data obtained from said scanning means to produce the preprocessed X-ray projection image data to be supplied to both of said scano data processing means and said CT image reconstructing means; and synthesizing means for synthesizing said scanogram and said X-ray CT image to be substantially displayed on said display means.
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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) | 1998-05-01 | 1998-10-31 | 1999-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-05-01 | 2002-10-31 | 2003-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-05-01 | 2006-10-31 | 2007-05-02 | $7700.00 | Window Closed / Lapsed |