Abstract
The radiobiologic level from an average direct-exposure, fine-grain mammograph approaches 4000 millirads. Copying reduced-exposure mammographs onto high gradient films yields a method of reducing radiation to the patient by a factor of 2. A mathematically based tone-reproduction system was developed in an attempt to produce acceptable facsimile images from a series of reduced-exposure mammographs. Acceptability was tested by radiologists using a sensitometric phantum. The radiologists were asked to quality rank a full exposure mammograph, facsimile mammographs, and a film-screen mammograph in terms of detectability of size and number of calcifications. Based on evidence, there is reason to believe that a facsimile mammograph produced with 50 percent normal radiation is diagnostically equivalent to a film/screen mammograph. However, even with this reduction in photographic and radiobiologic exposure, film/screen combination mammographs result in approximately 500 millirads, thus making them superior in terms of patient irradiation.
Library of Congress Subject Headings
Radiography
Publication Date
1977
Document Type
Thesis
Student Type
Graduate
Department, Program, or Center
School of Photographic Arts and Sciences (CIAS)
Advisor
Schumann, Gerhard
Recommended Citation
Richer, Stuart, "Increasing Visual Detectability in Reduced Exposure Mammography by Contrast Adjustment" (1977). Thesis. Rochester Institute of Technology. Accessed from
https://repository.rit.edu/theses/6743
Campus
RIT – Main Campus
Comments
Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014. Physical copy available through RIT's The Wallace Library at: RJ496.I6 D46 2009