&lt;title&gt;Image recording system characteristics for radiation therapy: portal localization and verification&lt;/title&gt;

Haus, Arthur G.; Dickerson, Robert E.; Huff, Kenneth E.; Bogucki, Terese M.

doi:10.1117/12.237779

Cited by 2 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A limitation with conventional radiation therapy portal images is low image contrast, due in part to the low attenuation of the exposing radiation by the anatomical parts being imaged and the contrast capabilities of the film or screen-film combination. [1][2][3][4][5][6] The purpose of this study was to design, develop and clinically evaluate a new screen-film combination for portal localization imaging that provides both significantly higher contrast and reduced film granularity, and, therefore, an expected improvement in image quality. 5,6 Comparison phantom and clinical images were made at two radiation oncology facilities with two screen-film combinations currently used for portal localization imaging and two new screen-film combinations.…”

mentioning

confidence: 99%

“…The current, commercially available screen-film combinations were a Kodak X-Omatic L radiation therapy cassette with a 1.0 mm thick copper front screen and a 0.25 mm thick lead back screen used in combination with Kodak T-Mat G/RA film and Kodak X-Omat RP film. [1][2][3][4] With these combinations, the film emulsion is exposed by electrons generated in the metal screens. It has previously been shown that significantly higher contrast can be realized from films exposed to light emission from fluorescent intensifying screens placed in contact with the metal screens.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Evaluation of a cassette‐screen‐film combination for radiation therapy portal localization imaging with improved contrast

et al. 1997

Self Cite

View full text Add to dashboard Cite

A traditional limitation with radiation therapy portal images is low image contrast, due in part to the low attenuation of the exposing radiation by the tissues being imaged, and the contrast capabilities of the image receptor. We have developed, and have clinically evaluated, a cassette-screen-film combination for portal localization imaging, which features a copper front screen plus Gd2O2S:Tb fluorescent screens and a slow-speed, fine grain, film emulsion with inherently high contrast coated on both sides of a 7 mil Estar base. The film can be processed in a conventional rapid-process film processor. Sensitometric data indicate that the film contrast (average gradient) for the new combination is approximately 3.5 times higher than the conventional portal localization systems in current use. The new combination has been clinically compared with two conventional systems. The required monitor unit settings were found to be similar. Initial clinical results indicate portal images made with the new combination are superior to those obtained with the conventional combinations. The images have much higher contrast, subjective impressions of lower noise, show clearer definition of structures, and are much easier to read.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Evaluation of a cassette‐screen‐film combination for radiation therapy portal localization imaging with improved contrast

et al. 1997

Self Cite

View full text Add to dashboard Cite

show abstract

<title>Development of a novel high-contrast cassette/film/screen system for radiation therapy portal localization imaging</title>

1997

View full text Add to dashboard Cite

Radiation therapy portal images have traditionally exhibited poor discrimination ofareas of interest, due to low subject contrast ofanatomical parts being imaged at megavoltage energies, and the contrast capabilities ofthe image receptors. As a result ofthis low contrast, positioning ofthe radiation beam and placement of shielding blocks can be difficult.A novel, high-contrast cassette/film/screen system has been developed and clinically evaluated for portal imaging. This system features a copper front screen, a gadolinium oxysuffide, terbium activated (GdO2S:Th) intensifying screens and a slow speed film with inherently high contrast. Veiy high film contrast is achieved by narrow grain size distribution and metal ion doping ofthe silver halide microczystals. This high-contrast film is exposed by light from the intensifying screen, further increasing contrast. Sensitometric data indicates this new system to have 3.5X greater contrast than conventional portal localization imaging systems at comparable monitor units (dose).Initial clinical evaluation indicates this new system to yield significantly superior images showing clearer definition of structures and was much easier to read and interpret.

show abstract

<title>Image recording system characteristics for radiation therapy: portal localization and verification</title>

Cited by 2 publications

References 0 publications

Evaluation of a cassette‐screen‐film combination for radiation therapy portal localization imaging with improved contrast

Evaluation of a cassette‐screen‐film combination for radiation therapy portal localization imaging with improved contrast

<title>Development of a novel high-contrast cassette/film/screen system for radiation therapy portal localization imaging</title>

Contact Info

Product

Resources

About