Patent US5063583A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5063583A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for testing radiographic film processors

Assignee: Thomas Jefferson University
•
Filing: 1989-11-24
•
Granted: 1991-11-05
•
Expires: 2009-11-24
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Methods and apparatus for determining film processor performance. Films for use in radiographic imaging, adapted to evaluate performance of a film processor which develops an image of a structure of interest on the films are provided. The films have exposable areas for radiographically imaging the structure of interest, and test means integrally located on the exposable areas for determining the performance of the processor which develops the radiographic image on the film. Additionally, methods of determining performance of film processors which develop radiographic images of structures of interest on films comprise the steps of shielding a first portion of the film from radiographic imaging of the structure of interest, imaging radiographically the structure of interest on a second portion of the film, impressing a test pattern on the first portion of the film, processing the film to develop the test pattern on the first portion of a film and the radiographic image of the structure of interest on the second portion of the film, and determining the performance of the film processor by visually comparing the test pattern to a control pattern. Methods and apparatus provided in accordance with the present invention eliminate the need for independent calibration of film processors that develop radiographic images on X-ray films and are particularly useful for determining the effect of the film processor on the diagnostic quality of mammograms.

Inventors

  • 👤 Benjamin M. Galkin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 09:51
CPC Classifications
G; G03; G03D; G03D13/00; G03D13/007; G03B; G03B42/00; G03B42/02; G03B42/04; G03B42/047; H; H05; H05G; H05G1/00; H05G1/08; H05G1/26; A; A61; A61B; A61B6/00; A61B6/58; A61B6/582; A61B6/583

Claims Analysis

Total Claims: 29
Claim 1
Independent Claim 309 words
A method of determining performance of a film processor which develops a radiographic image of a structure of interest on a film having an emulsion, comprising the steps of: shielding a first portion of the film along one edge of the film from x-ray energy used for imaging of the structure of interest, which edge is furthest from the structure of interest; impressing a first calibrated test pattern on the first portion of the film, said first pattern comprising a first calibrated graded stepwise density pattern having density positions, said density pattern produced by visible light, and a first plurality of symbols, located adjacent said first calibrated graded density pattern, wherein each symbol indicates the magnitude of one of said density positions; providing a control film of similar emulsion as the emulsion of said film; impressing a second calibrated test pattern along one edge of said control film said second calibrated test pattern comprising a second calibrated graded stepwise density pattern having density positions, said density pattern produced by visible light, and a second plurality of symbols, located adjacent said second calibrated graded density pattern, wherein each symbol indicates the magnitude of one of said density positions, wherein the step of impressing said first calibrated test pattern and said second calibrated test pattern are identical; processing the film in a film processor to develop the first calibrated test pattern on the first portion of the film and the radiographic image of the structure of interest on the second portion of the film; processing said control film to develop the second calibrated test pattern; and measuring the performance of the film processor used to develope the film by visually comparing and noting the symbols associated with those density positions between the first calibrated test pattern on the film and the second calibrated test pattern on the control film which match.
Claim 2
Independent Claim 309 words
A method of determining performance of a film processor which develops a radiographic image of a structure of interest on a film having an emulsion, comprising the steps of: shielding a first portion of the film along one edge of the film from x-ray energy used for imaging of the structure of interest, which edge is furthest from the structure of interest; impressing a first calibrated test pattern on the first portion of the film, said first pattern comprising a first calibrated graded stepwise density pattern having density positions, said density pattern produced by visible light, and a first plurality of symbols, located adjacent said first calibrated graded density pattern, wherein each symbol indicates the magnitude of one of said density positions; providing a control film of similar emulsion as the emulsion of said film; impressing a second calibrated test pattern along one edge of said control film said second calibrated test pattern comprising a second calibrated graded stepwise density pattern having density positions, said density pattern produced by visible light, and a second plurality of symbols, located adjacent said second calibrated graded density pattern, wherein each symbol indicates the magnitude of one of said density positions, wherein the step of impressing said first calibrated test pattern and said second calibrated test pattern are identical; processing the film in a film processor to develop the first calibrated test pattern on the first portion of the film and the radiographic image of the structure of interest on the second portion of the film; processing said control film to develop the second calibrated test pattern; and measuring the performance of the film processor used to develope the film by visually comparing and noting the symbols associated with those density positions between the first calibrated test pattern on the film and the second calibrated test pattern on the control film which match.
Claim 3
Dependent Claim 22 words
The method recited in claim 1 further comprising the step of coding the film on the first portion to identify the patient.
Claim 4
Dependent Claim 15 words
The method recited in claim 2 wherein the coding step is a photographic coding step.
Claim 5
Dependent Claim 21 words
The method recited in claim 1 wherein the second calibrated density pattern is precalibrated in terms of a plurality of parameters.
Claim 6
Dependent Claim 16 words
The method recited in claim 4 wherein the plurality of parameters is determined by densitometric analysis.
Claim 7
Dependent Claim 20 words
The method recited in claim 5 further comprising the step of identifying the film type and the control film type.
Claim 8
Dependent Claim 52 words
The method recited in claim 6 wherein the identifying step further comprises the steps of: comparing a first means for identifying film type formed on the film with a second means for identifying film type formed on the control film to ensure that the film and control film are of similar emulsion.
Claim 9
Dependent Claim 33 words
The method recited in claim 7 wherein the first means for identifying film type and the second means for identifying film type comprise at least one notch each oriented in a preferred direction.
Claim 10
Dependent Claim 13 words
The method recited in claim 7 wherein the radiographic image is a mammogram.
Claim 11
Independent Claim 123 words
A system for evaluating the performance of a radiographic imaging film processor, said system comprising: a radiographic imaging film of a first emulsion, comprising an exposable area for imaging a structure of interest using x-rays and a first calibrated graded density pattern impressed by light on a second area of said film, said second area being shielded from the effects of x-rays during imaging of the structure of interest; and a control film of a second emulsion, wherein said first and second emulsions are identical, said control film having a light induced second calibrated control density pattern, wherein the performance of the film processor which develops the radiographic image on the film is measured by comparing said first and second calibrated density patterns.
Claim 12
Independent Claim 123 words
A system for evaluating the performance of a radiographic imaging film processor, said system comprising: a radiographic imaging film of a first emulsion, comprising an exposable area for imaging a structure of interest using x-rays and a first calibrated graded density pattern impressed by light on a second area of said film, said second area being shielded from the effects of x-rays during imaging of the structure of interest; and a control film of a second emulsion, wherein said first and second emulsions are identical, said control film having a light induced second calibrated control density pattern, wherein the performance of the film processor which develops the radiographic image on the film is measured by comparing said first and second calibrated density patterns.
Claim 13
Dependent Claim 22 words
The system recited in claim 10 wherein the first calibrated graded density pattern is created from modulated light of known spectral characteristics.
Claim 14
Dependent Claim 19 words
The system recited in claim 10 wherein the calibrated control density pattern is photographically imaged on the control film.
Claim 15
Dependent Claim 21 words
The system recited in claim 12 wherein the calibrated control density pattern is precalibrated in terms of a plurality of parameters.
Claim 16
Dependent Claim 16 words
The system recited in claim 13 wherein the plurality of parameters is determined by densitometric analysis.
Claim 17
Dependent Claim 57 words
The system recited in claim 12 wherein the radiographic imaging film further comprises a first identifying means for identifying film type and wherein the control film further comprises second identifying means for identifying film type wherein said first and second identifying means serve to ensure that the film and the control film are of a same type.
Claim 18
Dependent Claim 136 words
A single emulsion film for use in mammography and adapted to evaluate changes in film fog, speed or contrast resulting from changes in the performance of a film processor which develops said film, said film comprising: a first area for imaging a structure of interest using x-rays; and calibrated test means, integrally located in a second area shielded from x-rays, for measuring the performance of the film processor which develops a radiographic image on the film, wherein said second area is located along an edge of said film and wherein said calibrated test means comprises a calibrated graded density pattern produced by visible light and positioned along said edge and a plurality of symbols, located adjacent said calibrated graded density pattern, wherein each symbol indicates the magnitude of a portion of said calibrated graded density pattern.
Claim 19
Dependent Claim 136 words
A single emulsion film for use in mammography and adapted to evaluate changes in film fog, speed or contrast resulting from changes in the performance of a film processor which develops said film, said film comprising: a first area for imaging a structure of interest using x-rays; and calibrated test means, integrally located in a second area shielded from x-rays, for measuring the performance of the film processor which develops a radiographic image on the film, wherein said second area is located along an edge of said film and wherein said calibrated test means comprises a calibrated graded density pattern produced by visible light and positioned along said edge and a plurality of symbols, located adjacent said calibrated graded density pattern, wherein each symbol indicates the magnitude of a portion of said calibrated graded density pattern.
Claim 20
Dependent Claim 23 words
The film recited in claim 16, wherein the calibrated test means is impressed on said second area by visible light from a sensitometer.
Claim 21
Dependent Claim 27 words
The film of claim 16, further comprising at least one notch cut in said film in a predetermined orientation to identify type of emulsion of said film.
Claim 22
Dependent Claim 193 words
A cassette for housing a single emulsion film during exposure to x-radiation in mammography to image a structure of interest on said film, said cassette comprising: a housing, having a front tube side and a back side; a single emulsion film disposed within the housing adjacent to said front tube side, wherein said single emulsion defines an emulsion surface, said film having a calibrated graded density pattern and a plurality of symbols located adjacent said calibrated graded density pattern impressed by light in a first film portion along one edge of said film, wherein each symbol indicates the magnitude of a part of said calibrated graded density pattern, said edge being farthest from the structure of interest during exposure; a single intensifying screen, disposed within said housing, said screen facing and pressed against said emulsion surface, for irradiating a second film portion with florescent energy induced by x-ray energy, thereby impressing an image of the structure of interest on the second film portion; first means for blocking x-ray energy from reaching said first film portion; and second means for maintaining the film in contact with said intensifying screen when said cassette is closed.
Claim 23
Dependent Claim 193 words
A cassette for housing a single emulsion film during exposure to x-radiation in mammography to image a structure of interest on said film, said cassette comprising: a housing, having a front tube side and a back side; a single emulsion film disposed within the housing adjacent to said front tube side, wherein said single emulsion defines an emulsion surface, said film having a calibrated graded density pattern and a plurality of symbols located adjacent said calibrated graded density pattern impressed by light in a first film portion along one edge of said film, wherein each symbol indicates the magnitude of a part of said calibrated graded density pattern, said edge being farthest from the structure of interest during exposure; a single intensifying screen, disposed within said housing, said screen facing and pressed against said emulsion surface, for irradiating a second film portion with florescent energy induced by x-ray energy, thereby impressing an image of the structure of interest on the second film portion; first means for blocking x-ray energy from reaching said first film portion; and second means for maintaining the film in contact with said intensifying screen when said cassette is closed.
Claim 24
Dependent Claim 29 words
The cassette recited in claim 19 wherein the intensifying screen further allows the calibrated graded density pattern to be impressed by light on the first portion of the film.
Claim 25
Dependent Claim 27 words
The cassette of claim 19, wherein said first means for blocking x-ray energy, blocks x-ray energy from reaching a portion of one edge of the intensifying screen.
Claim 26
Dependent Claim 41 words
The cassette of claim 19, wherein said housing, said intensifying screen and said film are rectangularly shaped and wherein said first film portion is located along a long edge of said film, said edge being furthest from the structure of interest.
Claim 27
Dependent Claim 15 words
The cassette of claim 22, wherein said intensifying screen is substantially co-extensive with said film.
Claim 28
Dependent Claim 32 words
The cassette of claim 22, wherein the area of said intensifying screen is smaller than said film so as to prevent production of florescent radiation that could reach said first film portion.
Claim 29
Dependent Claim 37 words
The cassette of claim 22, wherein the single intensifying screen further comprising an opaque strip located along a long edge of said screen to block florescent energy, induced by x-ray energy, from reaching said first film portion.

References Cited (Backward Citations)

US1973906A Cited
US2505562A Cited
DE2104252A1 Cited
US3864038A Cited
US4095111A Cited
US4860330A Cited
US4718757A Cited
US4788707A Cited
US4764948A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-11-04 1995-05-06 1995-11-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-11-04 1999-05-06 1999-11-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-11-04 2003-05-06 2003-11-05 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag