Patent US5612985A successfully refreshed from Google Patents.
US5612985A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Computer tomography apparatus
Assignee: Toshiba Corp
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Filing: 1995-10-24
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Granted: 1997-03-18
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Expires: 2015-10-24
Abstract
Abstract A computer tomography apparatus of the present invention can select one of an ON state in which X-ray radiation is performed to continuously acquire projection data and an OFF state in which acquisition of projection data is stopped, and even in the OFF state, rotation of an X-ray tube is continued, thus allowing quick switching from the OFF state to the ON state.
Inventors
- 👤 Yusuke Toki
- 👤 Manabu Hiraoka
- 👤 Ichiro Yamagishi
- 👤 Hiroyuki Onuki
- 👤 Tatsuya Ban
- 👤 Tetsuro Hada
- 👤 Takeo Nabatame
- 👤 Masao Yamahana
- 👤 Masakuni Fujise
- 👤 Yoshihiko Aochi
- 👤 Makoto Hayashibara
- 👤 Masahiro Ozaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:28
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/48; A61B6/481; A61B5/00; A61B5/24; A61B5/316; A61B5/318; A61B5/346; A61B5/349; A61B5/352; A61B6/02; A61B6/03; A61B6/032; A61B6/46; A61B6/461; A61B6/463; A61B6/482; A61B6/488; A61B6/50; A61B6/504; A61B6/027; A61B6/54; A61B6/541
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
214 words
A computer tomography apparatus which can perform an angiography, comprising: an X-ray tube which is supported to be continuously rotatable around an object to be examined; rotation control means for controlling rotation of said X-ray tube; X-ray control means for controlling X-ray radiation from said X-ray tube; data acquisition means, arranged to face said X-ray tube to sandwich the object to be examined therebetween, for acquiring projection data on the basis of an X-ray transmitted through the object to be examined; re-construction means for re-constructing tomographic image data on the basis of the projection data acquired by said data acquisition means; display means for displaying the re-constructed tomographic image data; and control means for controlling said rotation control means, said X-ray control means, said data acquisition means, and couch control means to execute a pre-scan at a first scan position, and controlling said rotation control means, said X-ray control means, said data acquisition means, and the couch control means to execute a main scan at a second scan position at a downstream of the first scan position, in which said control means starts the main scan after an elapse of a time required for a blood flow to reach the second scan position from the first scan position after the end of the pre-scan.
Claim 2
Dependent Claim
214 words
A computer tomography apparatus which can perform an angiography, comprising: an X-ray tube which is supported to be continuously rotatable around an object to be examined; rotation control means for controlling rotation of said X-ray tube; X-ray control means for controlling X-ray radiation from said X-ray tube; data acquisition means, arranged to face said X-ray tube to sandwich the object to be examined therebetween, for acquiring projection data on the basis of an X-ray transmitted through the object to be examined; re-construction means for re-constructing tomographic image data on the basis of the projection data acquired by said data acquisition means; display means for displaying the re-constructed tomographic image data; and control means for controlling said rotation control means, said X-ray control means, said data acquisition means, and couch control means to execute a pre-scan at a first scan position, and controlling said rotation control means, said X-ray control means, said data acquisition means, and the couch control means to execute a main scan at a second scan position at a downstream of the first scan position, in which said control means starts the main scan after an elapse of a time required for a blood flow to reach the second scan position from the first scan position after the end of the pre-scan.
Claim 3
Dependent Claim
31 words
An apparatus according to claim 1, in which said control means controls said rotation control means to continue rotation of said X-ray tube until the pre-scan and the main scan end.
Claim 4
Dependent Claim
51 words
An apparatus according to claim 1, further comprising: graph generation means for generating a graph representing a change in density in an ROI of the tomographic image data over time during the pre-scan, in which said display means displays the graph on a single screen together with the tomographic image data.
Claim 5
Dependent Claim
42 words
An apparatus according to claim 1, further comprising: input means for instructing end of the pre-scan when an operator determines that a density of a contrast medium has reached a predetermined density while observing a tomographic image displayed on said display means.
Claim 6
Dependent Claim
56 words
An apparatus according to claim 1, further comprising: discrimination means for discriminating if a density in an ROI of the tomographic image data reaches a predetermined density during the pre-scan, in which said control means controls said X-ray control means and said data acquisition means to end the pre-scan when said discrimination means makes the discrimination.
Claim 7
Dependent Claim
30 words
An apparatus according to claim 5, in which said discrimination means discriminates whether or not a total value of a plurality of pixels in the ROI reaches the predetermined density.
Claim 8
Dependent Claim
59 words
An apparatus according to claim 5, further comprising: graph generation means for generating a graph representing a change in density in the ROI of the tomographic image data over time during the pre-scan, in which said discrimination means discriminates whether or not an inclination of a tangent to the graph reaches a predetermined inclination corresponding to the predetermined density.
Claim 9
Dependent Claim
67 words
An apparatus according to claim 5, in which said control means controls said X-ray control means to radiate an X-ray only when said X-ray tube is at a specific angle, and said discrimination means discriminates whether or not a difference value between projection data obtained at the specific angle before the angiography and projection data obtained at the specific angle after the angiography reaches the predetermined density.
Claim 10
Dependent Claim
36 words
An apparatus according to claim 5, in which said discrimination means discriminates whether or not a difference value between tomographic image data before the angiography and tomographic image data after the angiography reaches the predetermined density.
Claim 11
Dependent Claim
75 words
A computer tomography apparatus according to claim 1, further comprising: measuring means for measuring one of a heartbeat waveform signal and a respiration waveform signal of the object to be examined; and second control means for controlling said rotation control means to continuously rotate said X-ray tube, and controlling said X-ray control means to radiate an X-ray in a specific phase in association with one of the heartbeat waveform signal and the respiration waveform signal.
Claim 12
Dependent Claim
50 words
An apparatus according to claim 10, in which said re-construction means re-constructs the tomographic data each time projection data required for re-constructing single tomographic image data are acquired, and said display means displays the tomographic image data after an elapse of a predetermined time from acquisition of the projection data.
Claim 13
Dependent Claim
35 words
An apparatus according to claim 10, in which said second control means controls said X-ray control means to continue X-ray radiation until projection data required for re-constructing at least one tomographic image data are acquired.
Claim 14
Dependent Claim
38 words
An apparatus according to claim 10, in which said second control means discriminates the specific phase by comparing an amplitude value of one of the heartbeat waveform signal and the respiration waveform signal with a predetermined threshold value.
Claim 15
Dependent Claim
47 words
A computer tomography apparatus according to claim 1, further comprising: remaining time calculation means for calculating a remaining time until said X-ray tube reaches a limit heat capacity when X-ray radiation is continued with a current X-ray energy; and second display means for displaying the remaining time.
Claim 16
Dependent Claim
26 words
An apparatus according to claim 14, further comprising: means for starting display of the remaining time when the remaining time becomes shorter than a predetermined time.
Claim 17
Dependent Claim
47 words
An apparatus according to claim 14, further comprising: alarm means for turning on a lamp or generating a tone; and control means for controlling said alarm means to turn on the light or to generate the tone when the remaining time becomes shorter than a predetermined time.
Claim 18
Dependent Claim
52 words
An apparatus according to claim 14, further comprising: control means for controlling said second display means to display a first message when the remaining time becomes shorter than a first time, and to display a second message when the remaining time becomes shorter than a second time shorter than the first time.
Claim 19
Dependent Claim
26 words
An apparatus according to claim 14, which said remaining time calculation means calculates the time remaining at the time of display on said second display means.
Claim 20
Dependent Claim
47 words
An apparatus according to claim 14, in which said remaining time calculation means calculates the remaining time corresponding to the current X-ray energy and another remaining time corresponding to another X-ray energy, and said second display means displays both the remaining time and the other remaining time.
Claim 21
Dependent Claim
180 words
A computer tomography apparatus according to claim 1, wherein said X-ray tube radiates a cone-shaped X-ray beam, further comprising: a two-dimensional detector array comprising a plurality of acquisition elements arranged to face said X-ray tube with the object to be examined sandwiched between said array and said X-ray tube, said acquisition elements acquiring projection data on the basis of an X-ray transmitted through the object to be examined; and second control means for executing a first mode for imaging a scanogram and a second mode for executing a scan in turn, for controlling said rotation control means to rotate said X-ray tube and controlling said X-ray control means to radiate the X-ray when said X-ray tube is at a specific angle in the first mode, for controlling said rotation control means to rotate said X-ray tube and controlling said X-ray control means to continuously radiate the X-ray in the second mode, and for controlling said rotation control means to continue rotation of said X-ray tube even while an operation mode is switched from the first mode to the second mode.
Claim 22
Dependent Claim
139 words
An apparatus according to claim 20, further comprising: a couch for slidably supporting a top plate on which the object to be examined is placed; and couch control means for controlling a sliding operation of said top plate; said second control means, when operating in the first mode, obtaining a plurality of scanograms by controlling said rotation control means to continuously rotate said X-ray tube, controlling said X-ray control means to repeat X-ray radiation when said X-ray tube is at the specific angle, and controlling said couch control means to intermittently move said top plate by a predetermined distance equal to a slice width of said two-dimensional detector array in synchronism with the X-ray radiation to obtain said plurality of scanograms, Which are coupled to said display means; and said display means displaying the coupled scanograms as one scanogram.
Claim 23
Dependent Claim
45 words
A apparatus according to claim 21, wherein said second control means controls said couch control means so that said top plate completes a sliding operation of the predetermined distance while said X-ray tube completes one revolution to have the specific angle as a start point.
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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) | 2000-03-17 | 2000-09-16 | 2001-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-03-17 | 2004-09-16 | 2005-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-03-17 | 2008-09-16 | 2009-03-18 | $7700.00 | Window Closed / Lapsed |