C Paraskevopoulou | PubMed Health

PubMed2006

Technique charts for Kodak EC-L film screen system for portal localization in a 6MV X-ray beam.

Port films are used in radiotherapy for visual evaluation of the radiation fields and subsequent quantitative analysis. Common port films suffer from poor image quality compared to the simulator-diagnostic films and is desirable to determine the appropriate exposure required for the best image contrast. The aim of this work is to generate technique charts for the Kodak EC-L film screen system for use in a 6MV x-ray beam. Three homogeneous water phantoms were used to simulate head-neck, thorax and abdomen dimensions of adult human, correspondingly. The film screen system was calibrated in a 6MV x-ray beam and under various irradiation conditions. The film screen system behavior was studied as a function of phantom thickness, field size and air gap between the phantom and the film screen system. In each case the optimum film exposure which produces the maximum image contrast was determined. The generated technique charts for the EC-L film screen system and for a 6 MV x-ray beam are used in our radiotherapy department for daily quality assurance of the radiotherapy procedure.

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PubMed1993

Indications for laparotomy after hydrostatic reduction for intussusception.

A criterion for successful hydrostatic reduction of intussusception is reflux into the terminal ileum. In our practice, absence of reflux into the terminal ileum is not an indication for laparotomy if the radiographic appearances suggest edema of the ileocecal valve. The aim of this study was to validate our approach. We reviewed the case notes of patients with a diagnosis of intussusception (n = 107; age 11.74 +/- 1.48 months; mean +/- SEM) treated from 1987 to 1991. Eleven required primary laparotomy for peritonitis. Ninety-six patients who had a contrast enema were studied. Edema of the ileocecal valve was defined as a persistent filling defect in the cecum after apparently complete hydrostatic reduction, without reflux of contrast into the distal small bowel. In 59 patients hydrostatic reduction was successful: 11 (18.6%) had edema of the ileocecal valve and no reflux contrast into the terminal ileum (group B). All improved clinically after the enema and needed no further treatment. In 37 patients hydrostatic reduction of the intussusception was unsuccessful and an operation was performed: 26 (70.3%) required manual reduction of the intussusception (group C) and 11 (29.7%) underwent bowel resection (group D). None of the patients with edema of ileocecal valve required further treatment or developed recurrent intussusception. In none of the patients who had an operation was the intussusception found to have been reduced by the contrast enema. There were no deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

Barium Sulfate↗