US4539987A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for coagulation by heat radiation
Assignee: Individual
•
Filing: 1984-06-04
•
Granted: 1985-09-10
•
Expires: 2004-06-04
Abstract
Abstract In a radiation coagulator having an electric incandescent lamp, in particular a tungsten-halogen low-voltage lamp, as radiation source, and a tissue contact element of a crystalline dielectric material transmissive to the radiation, forming a contact surface to be pressed against living body tissue, the temperature conductivity (reciprocal of the temperature resistance), the heat capacity of the contact element, possibly in combination with a heat sink attached thereto, is so great that the heat generated in the tissue in contact with said surface is derived in substantial measure from the tissue contact element. This prevents an over-rapid and over-intense temperature rise at the surface of the tissue, leading to a considerable improvement in coagulability, especially for severe parenchymatous hemorrhages, and to lessened adhesion to the contact surface, and permitting a gentle coagulation, extending into depth if desired. Besides, the tissue contact element is free from any exposed sharp edges that might cut into the tissue and injure it or cause an excessive concentration of radiation. A preferred material for the tissue contact element is monocrystalline sapphire; other suitable materials are beryllium or magnesium oxide, or monocrystalline quartz.
Inventors
- 👤 Gunther Nath
- 👤 Albert Kreitmair
- 👤 Vincent Jaeger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:31
CPC Classifications
A; A61; A61B; A61B18/00; A61B18/04; A61B18/08; A61B18/082; A61B18/18; A61B18/20; A61B18/22; A61B18/28; A61B2018/00005; A61B2018/00011; A61B2018/1807
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
150 words
In a radiation coagulation apparatus for applying radiation to a limited area of living tissue by direct contact of said apparatus therewith, said coagulation apparatus comprising an incandescent electric filament as a source of heat radiation, a housing enclosing said electric filament, and a radiation exit system including a tissue contact element of a crystalline dielectric material transmissive to the radiation forming a contact surface to be applied against said body tissue through which said radiation traverses, the improvement wherein said tissue contact element is comprised of sapphire, and has a radiation entrance surface facing said electric filament, and has an average thickness of at least 4 mm measured between the radiation entrance surface and the tissue contact surface in the direction of the radiation; and the radiation output density of said radiation source at the tissue contact surface of said contact element is at most 150 watts/cm 2 .
Claim 2
Dependent Claim
150 words
In a radiation coagulation apparatus for applying radiation to a limited area of living tissue by direct contact of said apparatus therewith, said coagulation apparatus comprising an incandescent electric filament as a source of heat radiation, a housing enclosing said electric filament, and a radiation exit system including a tissue contact element of a crystalline dielectric material transmissive to the radiation forming a contact surface to be applied against said body tissue through which said radiation traverses, the improvement wherein said tissue contact element is comprised of sapphire, and has a radiation entrance surface facing said electric filament, and has an average thickness of at least 4 mm measured between the radiation entrance surface and the tissue contact surface in the direction of the radiation; and the radiation output density of said radiation source at the tissue contact surface of said contact element is at most 150 watts/cm 2 .
Claim 3
Dependent Claim
62 words
A radiation coagulator according to claim 1, wherein the specific heat capacity and thermal conductivity of said radiation exit system each have a relatively high value such that the temperature at the contact surface of said contact element, while adjacent to body tissue and traversed by the radiation from the heat radiation source, will increase at most 50° C. with 2 seconds.
Claim 4
Dependent Claim
33 words
A radiation coagulator according to claim 1 or 2, wherein the tissue contact element has a relatively smooth surface and wherein the edges that can come into contact with body tissue are rounded.
Claim 5
Dependent Claim
39 words
A radiation coagulator according to claim 1 or 2 further including a heat sink, and wherein the side of a portion of said tissue contact element traversed by the radiation is in good heat-conductive communication with said heat sink.
Claim 6
Dependent Claim
55 words
A radiation coagulator according to claim 1, wherein the tissue contact element, at least adjacent to the radiation entrance surface facing said electric filament, is round in cross section with a diameter of at least 4 mm and is at least 6 mm in length in the direction of the radiation through the contact element.
Claim 7
Dependent Claim
45 words
A radiation coagulator according to claim 1, wherein the source of heat radiation is an electric incandescent lamp and wherein the region of said contact element adjoining said radiation source is cylindrical for at least 5 mm in length in the direction of the radiation.
Claim 8
Dependent Claim
43 words
A radiation coagulator according to claim 6, wherein the incandescent filament is substantially surrounded by an envelope, and the radiation entrance surface of said contact element is spaced apart from, but at most 10 mm distant from, the envelope of the incandescent filament.
Claim 9
Dependent Claim
19 words
A radiation coagulator according to claim 7, wherein the tissue contact element is at least 10 mm in length.
Claim 10
Dependent Claim
24 words
A radiation coagulator according to claim 8, wherein the contact element comprises a tip of diminishing cross section away from the source of radiation.
Claim 11
Dependent Claim
13 words
A radiation coagulator according to claim 9, wherein the diminishing tip is wedge-shaped.
Claim 12
Dependent Claim
32 words
A radiation coagulator according to claim 7, wherein the housing enclosing said incandescent filament includes a subtantially ellipsoidal reflector at a radial distance of at most 5 mm from said incandescent filament.
Claim 13
Dependent Claim
30 words
A radiation coagulator according to claim 6, wherein the lamp has a rating of 150 W and the diameter of the cylindrical region of said contact element is 12 mm.
Claim 14
Dependent Claim
30 words
A radiation coagulator according to claim 6, wherein the lamp has a rating of 250 W and the diameter of the cylindrical region of said contact element is 16 mm.
Claim 15
Dependent Claim
30 words
A radiation coagulator according to claim 6, wherein the lamp has a rating of 400 W and the diameter of the cylindrical region of said contact element is 25 mm.
Claim 16
Dependent Claim
15 words
A radiation coagulator according to claim 1, wherein the tissue contact element is a monocrystal.
Claim 17
Dependent Claim
29 words
A radiation coagulator according to claim 1, wherein the tissue contact element contains a material imparting an increased absorption thereto in the green and blue band of the spectrum.
Claim 18
Dependent Claim
33 words
A radiation coagulator according to claim 1, wherein an optical filter having a pass band from about 0.6μ to about 1.4μ is arranged between the source of radiation and the tissue contact element.
Claim 19
Dependent Claim
26 words
A radiation coagulator according to claim 1, wherein the source of radiation is an incandescent lamp having an electric power rating of at least 100 W.
Claim 20
Dependent Claim
27 words
A radiation coagulator according to claim 1, wherein the output density of the incoherent radiation is at least 10 watts per square centimeter at the contact surface.
Claim 21
Dependent Claim
18 words
A radiation coagulator according to claim 1, wherein the output density is at most 100 watts/cm 2 .
Claim 22
Dependent Claim
24 words
A radiation coagulator according to claim 1, wherein the tissue contact element has a disc shape and is optically polished on its circumferential surface.
Claim 23
Dependent Claim
24 words
A radiation coagulator according to claim 1 further including a generally cylindrical tube member which encircles the tissue contact element, to thereby reduce glare.
Claim 24
Dependent Claim
15 words
A radiation coagulator according to claim 1 wherein said housing comprises a generally cylindrical tube.
Claim 25
Dependent Claim
13 words
A radiation coagulator according to claim 23, wherein said tube is generally straight.
Claim 26
Dependent Claim
19 words
A radiation coagulator according to claim 23, wherein said tube has a bend of about 45° in its middle.
Claim 27
Dependent Claim
33 words
A radiation coagulator according to claim 23, wherein said tissue contact element is mounted at the end of the tube so that the radiation path is generally coaxial with the cylindrical tube's axis.
References Cited (Backward Citations)
DE2717421A1
Cited
US4233493A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-09 | 1989-03-11 | 1989-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-09 | 1993-03-11 | 1993-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-09 | 1997-03-11 | 1997-09-10 | $7700.00 | Window Closed / Lapsed |