Radiotherapy verification film for estimating cumulative entrance skin exposure for fluoroscopic examinations

Journal Article · Sat Sep 01 04:00:00 EDT 1990 · Health Physics; (USA)

DOI:https://doi.org/10.1097/00004032-199009000-00004· OSTI ID:6509377

Geise, R A; Ansel, H J ^[1]

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1. Univ. of Minnesota, Minneapolis (USA)

Measurement of skin entrance exposures during fluoroscopic procedures is complicated by the use of automatic exposure control devices and the presence of contrast media. Due to variability in positioning spot films from patient to patient, standard dosimeters, such as thermoluminescent, cannot be properly placed on the skin prior to examination. Prepackaged film of the type used for portal verification in radiation therapy held next to the patient's skin in a specially modified patient examination gown was found to be useful for determining the entrance skin exposure from both fluoroscopy and spot films during air contrast barium enema exams. The usable sensitivity range of this film has been found satisfactory for exposure measurements at exposures and kVps typically used for gastrointestinal fluoroscopic procedures. Errors in exposure estimates due to changes in film speed and contrast with kVp are less than 5% for the range of kVps used. Errors from variations in beam quality due to the adjacency of scattering material are approximately 5%. Entrance exposures determined with film agreed with those determined from TLD measurements to within 21%, with an average difference of 9%.

• OSTI ID: 6509377
• Journal Information: Health Physics; (USA), Journal Name: Health Physics; (USA) Vol. 59:3; ISSN 0017-9078; ISSN HLTPA
• Country of Publication: United States
• Language: English

Related Subjects

560151* -- Radiation Effects on Animals-- Man
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOMEDICAL RADIOGRAPHY
BODY
DATA COVARIANCES
DIAGNOSTIC TECHNIQUES
DIGESTIVE SYSTEM
DOSEMETERS
DOSES
DOSIMETRY
FILM DOSIMETRY
GASTROINTESTINAL TRACT
LUMINESCENT DOSEMETERS
MEASURING INSTRUMENTS
MEDICINE
NUCLEAR MEDICINE
ORGANS
RADIATION DOSES
RADIOLOGY
SKIN
THERMOLUMINESCENT DOSEMETERS