US5984853A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Miniaturized source of ionizing radiation and method of delivering same
Assignee: Radi Medical Technologies AB
•
Filing: 1997-02-25
•
Granted: 1999-11-16
•
Expires: 2017-02-25
Abstract
Abstract A method and apparatus of creating a miniaturized source of radiation and delivering radiation to a location such as therapy location. The radiation source comprises a member made of a material emitting electrons when energy is supplied to the member. There is an electron retarding member disposed opposite the electron emitting member, and the electron retarding member is made of a material emitting ionizing radiation when electrons are retarded therein. The radiation source is further provided on an elongated member in the distal region thereof, and the elongated member is insertable into the body.
Inventors
- 👤 Leif Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:57
CPC Classifications
A; A61; A61N; A61N5/00; A61N5/10; A61N5/1001; H; H01; H01J; H01J35/00; H01J35/32
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
102 words
The method of invasively delivering radiation to a therapy location in a living body, comprising: a) forming a miniaturized source of ionizing radiation on a support comprising at least one plate member, including a pair of electrodes in the form of an anode and a cathode on the support; b) inserting the source into a living body and directing the source at the therapy location; and c) activating the source of ionizing radiation by selectively energizing and deenergizing the source so as to direct a highly accelerated electron emission from the cathode to the anode in the vicinity of the therapy location.
Claim 2
Independent Claim
102 words
The method of invasively delivering radiation to a therapy location in a living body, comprising: a) forming a miniaturized source of ionizing radiation on a support comprising at least one plate member, including a pair of electrodes in the form of an anode and a cathode on the support; b) inserting the source into a living body and directing the source at the therapy location; and c) activating the source of ionizing radiation by selectively energizing and deenergizing the source so as to direct a highly accelerated electron emission from the cathode to the anode in the vicinity of the therapy location.
Claim 3
Dependent Claim
29 words
The method of claim 1, wherein the high electron emission is created by applying a positive voltage on the anode to cause electrons to be emitted from the cathode.
Claim 4
Dependent Claim
12 words
The method of claim 2, wherein the voltage is in kV range.
Claim 5
Dependent Claim
30 words
The method of claim 1, wherein the high electron emission is created by heating the cathode to a high temperature, giving rise to thermal emission of electrons toward the anode.
Claim 6
Dependent Claim
15 words
The method of claim 1, including, retarding the electron emission by impact at the anode.
Claim 7
Dependent Claim
23 words
The method of claim 1, including forming the anode of a metal selected from a group consisting of tungsten, molybdenum, cobalt and aluminium.
Claim 8
Dependent Claim
19 words
The method of claim 1, including forming the anode of a metal having an atomic number higher than 50.
Claim 9
Dependent Claim
22 words
The method of claim 7, including depositing the anode metal in the form of a thin film on a first plate member.
Claim 10
Dependent Claim
27 words
The method of claim 8, including forming the cathode with a thin deposited film of a material having a low work function on a second plate member.
Claim 11
Dependent Claim
15 words
The method of claim 9, including forming a miniature platform formed by the plate members.
Claim 12
Dependent Claim
20 words
The method of claim 10, including connecting the anode and cathode to a voltage source by deposition of metallic strips.
Claim 13
Dependent Claim
16 words
The method of claim 1 wherein the support includes a first plate and a second plate.
Claim 14
Dependent Claim
36 words
The method of claim 12, including forming the first and second plates of a semiconductor material and doping leads therein, and connecting the anode and cathode to a voltage source by doping leads onto the semiconductor.
Claim 15
Dependent Claim
33 words
The method of claim 12, including forming a microcavity in one of the first and second plates, and forming at least the cathode in the microcavity and the anode on the other plate.
Claim 16
Dependent Claim
21 words
The method of claim 12, including forming the microcavity by etching off a sacrificial layer between the first and second plates.
Claim 17
Dependent Claim
16 words
The method of claim 12, including adhesively bonding adjoining surfaces of the first and second plates.
Claim 18
Dependent Claim
20 words
The method of claim 12, including forming at least one of the first and second plates of simple crystalline silicone.
Claim 19
Dependent Claim
22 words
The method of claim 1, including forming the anode at least partly of a metal having an atomic number greater than 20.
Claim 20
Dependent Claim
27 words
The method of claim 1, including forming a third electrode in the form of a gate within the microcavity, controlling the electronic current emitted toward the anode.
Claim 21
Dependent Claim
16 words
The method of claim 1, including isolating the electrodes to prevent short circuits and current leakage.
Claim 22
Dependent Claim
20 words
The method of claim 1, including forming a sharp tip in the microcavity and forming the cathode on the tip.
Claim 23
Dependent Claim
26 words
The method of claim 1, including determining a desired radiation level and duration of radiation, and energizing the source to achieve the desired level and duration.
Claim 24
Dependent Claim
16 words
The method of claim 22, including deenergizing the source and withdrawing the source from the location.
Claim 25
Dependent Claim
24 words
The method of claim 22, including repeating the steps of inserting the source, deenergizing the source and withdrawing the source at selected time intervals.
Claim 26
Dependent Claim
36 words
The method of claim 1, including encompassing the source within a cannula element comprising material transparent to emitted radiation, penetrating tissue of the living body and directing the source in the cannula to the therapy location.
Claim 27
Dependent Claim
32 words
The method of claim 25, including connecting electrical leads to the anode and the cathode, connecting insulated wires to the leads and extending the wires through the cannula to a power source.
Claim 28
Dependent Claim
16 words
The method of claim 1, including mounting the source near a distal end of a wire.
Claim 29
Dependent Claim
25 words
The method of claim 27, including inserting a catheter into body tissue, and directing the source and wire through the catheter to the therapy location.
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) | 2002-11-15 | 2003-05-17 | 2003-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-11-15 | 2007-05-17 | 2007-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-11-15 | 2011-05-17 | 2011-11-16 | $7700.00 | Window Closed / Lapsed |