US3906233A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System and method for administering radiation
Assignee: Varian Medical Systems Inc
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Filing: 1973-10-12
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Granted: 1975-09-16
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Expires: 1993-10-12
Abstract
Abstract A system and method for metering the quantity of radiation administered a subject by a source of radiation movable along a path relative to the subject. The system cumulatively counts the amount of radiation directed toward the subject during each of a succession of increments of motion of the source. When a predetermined amount of radiation is delivered during an increment, the source is disabled until the source passes into the next increment of displacement. The count of radiation is restarted at the instant the source is disabled, to accumulate accurately any added spurious radiation dosage which may occur and to include that dosage in the count of the permitted amount for the next succeeding increment of motion. Several interlocks for disabling the system in response to various malfunctions are included. Means for controlling the speed of movement of the source and/or the dose rate of the source are also included.
Inventors
- 👤 Thomas M Vogel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:51
CPC Classifications
G; G21; G21K; G21K5/00; G21K5/10; A; A61; A61N; A61N5/00; A61N5/01
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
267 words
A system for metering the quantity of radiation of a subject by an apparatus including a radiation source, said system comprising: a. means for causing relative movement between the source and the subject along a path; b. means for sensing the relative movement along traversal of a plurality of increments of the path; c. means for sensing the amount of radiation from the source toward the subject during the traversal of each of said increments; d. means connected to said radiation sensing means for cumulatively counting said sensed amount of radiation from the source toward the subject during the traversal of each of said increments and generating a counting signal which is a function of said counted amount of radiation; e. presetting means generating a radiation limit signal which is a function of a predetermined quantity of radiation to be delivered during each of said increments; f. comparing means connected to said counting and presetting means for producing a stop signal when the amount of radiation counted by said counting means becomes substantially equal to said predetermined amount; g. means connected to said comparing means for disabling the source in response to the production of said stop signal; h. said traversal sensing means producing an enabling signal in response to traversal of said motion across the initial boundary of each of said increments; i. enabling means responsive to the occurrence of said enabling signal for enabling the source to resume emission of radiation; whereby the amount of radiation delivered to the subject during the traversal of each of said increments is substantially limited to said predetermined amount.
Claim 2
Independent Claim
267 words
A system for metering the quantity of radiation of a subject by an apparatus including a radiation source, said system comprising: a. means for causing relative movement between the source and the subject along a path; b. means for sensing the relative movement along traversal of a plurality of increments of the path; c. means for sensing the amount of radiation from the source toward the subject during the traversal of each of said increments; d. means connected to said radiation sensing means for cumulatively counting said sensed amount of radiation from the source toward the subject during the traversal of each of said increments and generating a counting signal which is a function of said counted amount of radiation; e. presetting means generating a radiation limit signal which is a function of a predetermined quantity of radiation to be delivered during each of said increments; f. comparing means connected to said counting and presetting means for producing a stop signal when the amount of radiation counted by said counting means becomes substantially equal to said predetermined amount; g. means connected to said comparing means for disabling the source in response to the production of said stop signal; h. said traversal sensing means producing an enabling signal in response to traversal of said motion across the initial boundary of each of said increments; i. enabling means responsive to the occurrence of said enabling signal for enabling the source to resume emission of radiation; whereby the amount of radiation delivered to the subject during the traversal of each of said increments is substantially limited to said predetermined amount.
Claim 3
Dependent Claim
44 words
The system of claim 1 further comprising counter reset means for resetting said counting means to zero upon the occurrence of said stop signal, whereby any radiation delivered after occurrence of said stop signal is added to the count for the next succeeding increment.
Claim 4
Dependent Claim
23 words
The system of claim 1, in which said path is arcuate, and the center of said arcuate path is proximate to the subject.
Claim 5
Dependent Claim
69 words
The system of claim 1, further comprising: a. supplemental disabling means for disabling the radiation source; and b. additional counter means for counting the radiation delivered by the source, said additional counter means being connected to said supplemental disabling means for actuating said supplemental disabling means upon the emission of a predetermined quantity of radiation by the source during the period between said stop signal and said enabling signal.
Claim 6
Dependent Claim
61 words
The system of claim 1, further comprising: a. supplemental disabling means for disabling the radiation source; and b. timer means connected between said traversal sensing means and said supplemental disabling means for actuating said supplemental disabling means for disabling the source contingent on the failure of the source to traverse any said increments of said path within a predetermined time duration.
Claim 7
Dependent Claim
57 words
The system of claim 5, wherein: a. said path comprises an arc, centered substantially at the location of the subject; b. said increment comprises two degrees of said arc; and c. said timer means is responsive to the lapse of 0.08 minutes during which the source traverses said two degree increment to actuate said supplemental disabling means.
Claim 8
Dependent Claim
71 words
The system of claim 1, further comprising: a. supplemental disabling means for disabling the radiation source; and b. another counter means connected among said comparing means and said means for sensing the traversal of each of said increments and said supplemental disabling means, said another counter means being responsive to the failure of occurrence of said stop signal during the traversal any of said increments to actuate said supplemental disabling means.
Claim 9
Dependent Claim
24 words
The system of claim 4, wherein: said supplemental disabling means comprises cutoff means for interrupting the transmission of high voltage power to said system.
Claim 10
Dependent Claim
24 words
The system of claim 5 wherein: said supplemental disabling means comprises cutoff means for interrupting the transmission of high voltage power to said system.
Claim 11
Dependent Claim
24 words
The system of claim 7, wherein: said supplemental disabling means comprises cutoff means for interrupting the transmission of high voltage power to said system.
Claim 12
Dependent Claim
80 words
The system of claim 1, further comprising; a. speed control means responsive to a speed control signal for governing the speed at which said drive means causes the source to traverse said path, said speed being a function of said speed control signal; and b. decoder means connected between said presetting means and said speed control means and being responsive to the magnitude of said radiation limit signal for generating said speed control signal as a function of said magnitude.
Claim 13
Dependent Claim
14 words
The system of claim 11, wherein said speed control means comprises a programable amplifier.
Claim 14
Dependent Claim
26 words
The system of claim 11, wherein the magnitude of said speed control signal is substantially an inverse function of the magnitude of said radiation limit signal.
Claim 15
Dependent Claim
87 words
The system of claim 1 further comprising: a. position sensing means connected to the source for generating a position signal as a function of the position of the source along said path; b. position preset means for generating a position limit signal which is a function of a predetermined position limit of the source; c. position comparing means connected between said position sensing means and said position preset means for generating an index signal when the position of the source substantially corresponds with said predetermined position limit.
Claim 16
Dependent Claim
22 words
The system of claim 14, further comprising: movement stopping means responsive to the occurrence of said index signal for halting said movement.
Claim 17
Dependent Claim
25 words
The system of claim 14, further comprising: means responsive to the occurrence of said index signal for cutting off high voltage power to said system.
Claim 18
Dependent Claim
85 words
The system of claim 1, further comprising: a. additional counter means for counting the radiation from the source; and b. additional comparing means connected to said presetting means and to said additional counter means for producing a supplemental stop signal if said additional counter means signals the additional comparing means that the radiation delivered for any of said increments is more than was preset in said presetting means; and c. supplemental disabling means for disabling the radiation source in response to said supplemental stop signal.
Claim 19
Dependent Claim
24 words
The system of claim 17 wherein said additional counter means does not count the first two counts it receives for each of said increments.
Claim 20
Dependent Claim
30 words
The system of claim 17 further comprising supplemental means for sensing the amount of radiation from the source, and said additional counter means is connected to said supplemental sensing means.
Claim 21
Dependent Claim
60 words
The system of claim 1, further comprising: a. dose rate control means responsive to a dose rate control signal for governing the dose rate delivered by the source; and b. decoder means connected between said presetting means and said dose rate control means and being responsive to the magnitude of said radiation limit signal as a function of said magnitude.
Claim 22
Dependent Claim
27 words
The system of claim 20 wherein the magnitude of said dose rate control signal is substantially an increasing function of the magnitude of said radiation limit signal.
Claim 23
Independent Claim
241 words
A method for metering the quantity of radiation of a subject delivered by means of an apparatus including a radiation source, means being provided for causing relative movement between the source and the subject over a path, said method comprising the steps of: a. controlledly causing said relative movement along the path; b. sensing the traversal of a plurality of increments along said path; c. sensing the amount of radiation emanating from the source toward the subject during the traversal of each of said increments; d. cumulatively counting said amount of radiation emanated by the source toward the subject during the traversal of each of said increments and generating a counting signal in response thereto, said counting signal being a function of said counted amount of radiation, e. generating a radiation limit signal which is a function of a predetermined desired quantity of radiation emanated by the source toward the subject during each of said increments; f. comparing said radiation limit signal with said counting signal and producing a stop signal when the amount of radiation corresponding to the counting signal substantially equals said predetermined quantity of radiation; g. disabling the source in response to the occurrence of said stop signal; h. producing an enabling signal in response to the passage of said source across the boundary of each of said increments; and i. reenabling the source to resume emission of radiation in response to the occurrence of said enabling signal.
Claim 24
Independent Claim
241 words
A method for metering the quantity of radiation of a subject delivered by means of an apparatus including a radiation source, means being provided for causing relative movement between the source and the subject over a path, said method comprising the steps of: a. controlledly causing said relative movement along the path; b. sensing the traversal of a plurality of increments along said path; c. sensing the amount of radiation emanating from the source toward the subject during the traversal of each of said increments; d. cumulatively counting said amount of radiation emanated by the source toward the subject during the traversal of each of said increments and generating a counting signal in response thereto, said counting signal being a function of said counted amount of radiation, e. generating a radiation limit signal which is a function of a predetermined desired quantity of radiation emanated by the source toward the subject during each of said increments; f. comparing said radiation limit signal with said counting signal and producing a stop signal when the amount of radiation corresponding to the counting signal substantially equals said predetermined quantity of radiation; g. disabling the source in response to the occurrence of said stop signal; h. producing an enabling signal in response to the passage of said source across the boundary of each of said increments; and i. reenabling the source to resume emission of radiation in response to the occurrence of said enabling signal.
Claim 25
Dependent Claim
50 words
The method of claim 22 further comprising the step of reinitiating the counting of said radiation emanating from the source toward the subject upon the occurrence of said stop signal, whereby any radiation delivered after occurrence of said stop signal is added to the count for the next succeeding increment.
Claim 26
Dependent Claim
31 words
The method of claim 22, wherein the step of causing said relative movement along said path comprises driving said source along an arcuate path having its center located proximate the subject.
Claim 27
Dependent Claim
75 words
The method of claim 22, further comprising the steps of: a. further sensing the quantity of radiation emanating from the source toward the subject during said period in which the source is disabled; b. counting said radiation emanating during the period of disablement; and c. actuating a supplemental disabling means for additionally disabling the source upon the emission of a predetermined quantity of radiation by the source during said period of disablement of the source.
Claim 28
Dependent Claim
38 words
The method of claim 22, further comprising the step of; actuating a supplementaL disabling means for disabling the source contingent upon the failure of the source to traverse said increment of said path within a predetermined time duration.
Claim 29
Dependent Claim
67 words
The method of claim 26 wherein: a. said movement causing step comprises moving the source along an arcuate path centered substantially at the location of the subject; b. said increment comprises two degrees of said arc; and c. said step of actuating said supplemental disabling means comprises actuating said supplemental disabling means if 0.08 minutes elapse during the traversal by the source of said two degree increment.
Claim 30
Dependent Claim
43 words
The method of claim 22, further comprising the steps of: a. actuating a supplemental disabling means for disabling the source in response to the failure of occurrence of said stop signal during the traversal by the source of said one increment of motion.
Claim 31
Dependent Claim
46 words
The method of claim 22, further comprising the steps of: a. generating a speed control signal, said speed control signal being a function of said radiation limit signal; and b. controlling the speed of the traversal in response to the value of said speed control signal.
Claim 32
Dependent Claim
63 words
The method of claim 22, further comprising the steps of: a. generating a position signal, said position signal being a function of the position of movement along said path; b. detecting the attainment by said position signal of a predetermined value; and c. generating an index signal in response to the detection of the attainment of said predetermined value by the position signal.
Claim 33
Dependent Claim
30 words
The method of claim 22 further comprising controlling the dose rate delivered by the source and the speed of movement along the path as a function said radiation limit signal.
Claim 34
Independent Claim
113 words
A method for metering the quantity of radiation of a subject delivered by means of an apparatus including a radiation source, the source being selectively movable relative to the subject over a path, said method comprising the steps of: a. controlledly driving the source along the path; b. sensing the traversal by the source of at least one increment of the path; c. sensing the amount of radiation emanating from the source toward the subject during the traversal of said increment; and d. disabling the source from further delivery of radiation in response to the attainment of a predetermined cumulative amount of radiation emanating from the source during the traversal of said increment.
Claim 35
Independent Claim
113 words
A method for metering the quantity of radiation of a subject delivered by means of an apparatus including a radiation source, the source being selectively movable relative to the subject over a path, said method comprising the steps of: a. controlledly driving the source along the path; b. sensing the traversal by the source of at least one increment of the path; c. sensing the amount of radiation emanating from the source toward the subject during the traversal of said increment; and d. disabling the source from further delivery of radiation in response to the attainment of a predetermined cumulative amount of radiation emanating from the source during the traversal of said increment.
Claim 36
Independent Claim
117 words
A system for metering the quantity of radiation of a subject by an apparatus including a radiation source, the source being selectively movable relative to the subject over a path, said system comprising: a. means for driving the source along the path; b. means for sensing the traversal by the source of at least one increment of the path; c. means for sensing the quantity of radiation emanating from the source toward the subject during the traversal of said increment; and d. means responsive to said radiation sensing means for disabling the source in response to the accumulation of a predetermined quantity of radiation emanating from the source toward the subject during the traversal of said increment.
Claim 37
Independent Claim
117 words
A system for metering the quantity of radiation of a subject by an apparatus including a radiation source, the source being selectively movable relative to the subject over a path, said system comprising: a. means for driving the source along the path; b. means for sensing the traversal by the source of at least one increment of the path; c. means for sensing the quantity of radiation emanating from the source toward the subject during the traversal of said increment; and d. means responsive to said radiation sensing means for disabling the source in response to the accumulation of a predetermined quantity of radiation emanating from the source toward the subject during the traversal of said increment.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |