title: Quality of portal verification images using GLP7 film.
abstract: OBJECTIVE
  To improve portal verification radiographs, we tested the application of GLP7 film.
  
  
  METHODS
  The quality of the portal verification radiograph using the XV cassette-GLP7 film combination and the XL cassette-GLP7 film combination was investigated. The XV cassette-XV2 film combination and the SA cassette-GS screen-XTL film combination also were used for comparison.
  
  
  RESULTS
  The characteristic curves showed that the relative speeds were 0.32 and 0.47 for the XV-GLP7 and XL-GLP7 combinations and that the average gradients were 1.93, 2.14, and 1.32 for the XV-GLP7, XL-GLP7, and XV-XV2 combinations, respectively. In the experiment using Burger's phantom, the smallest visible volumes were 11.8, 11.3, 28.7, and 19.6 mm3 for the XV-GLP7, XL-GLP7, XV-XV2, and SA-GS-XTL combinations, respectively. In the lower dosage treatment in the clinic, there were no marked differences between the GLP7 film and XV2 film. However, in the higher dosage treatment, the GLP7 film had a better quality than did the XV2 film.
  
  
  CONCLUSIONS
  Portal verification radiographs using GLP7 film are of sufficient quality for clinical use.
authors.affiliation: Department of Radiology, Osaka-Prefectural Habikino Hospital, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tada
authors.forename: T
authors.initials: T
authors.lastname: Fujioka
authors.forename: M
authors.initials: M
authors.lastname: Sakurai
authors.forename: R
authors.initials: R
authors.lastname: Yamaguchi
authors.forename: K
authors.initials: K
authors.lastname: Minakuchi
authors.forename: T
authors.initials: T
authors.lastname: Kozuka
authors.forename: T
authors.initials: T
authors.lastname: Nakajima
authors.forename: M
authors.initials: M
authors.lastname: Nishioka
mesh_terms: D006801:Humans; D011168:Portal System / Q000000981:diagnostic imaging*; D011859:Radiography; D013679:Technology, Radiologic; D014962:X-Ray Film