Journal of Medical Physics
 Home | Search | Ahead of print | Current Issue | Archives | Instructions | Subscription | Login  The official journal of AMPI, IOMP and AFOMP      
 Users online: 293  Home  EMail this page Print this page Decrease font size Default font size Increase font size 
Year : 2007  |  Volume : 32  |  Issue : 4  |  Page : 175-184

Computer simulations and models for the performance characteristics of spectrally equivalent X-ray beams in medical diagnostic radiology

Department of Physics, Obafemi Awolowo University 220005, Ile-Ife Osun, Nigeria

Correspondence Address:
Akintunde A Okunade
Department of Physics, Obafemi Awolowo University 220005, Ile-Ife Osun
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0971-6203.37483

Rights and Permissions

In order to achieve uniformity in radiological imaging, it is recommended that the concept of equivalence in shape (quality) and size (quantity) of clinical X-ray beams should be used for carrying out the comparative evaluation of image and patient dose. When used under the same irradiation geometry, X-ray beams that are strictly or relatively equivalent in terms of shape and size will produce identical or relatively identical image quality and patient dose. Simple mathematical models and software program EQSPECT.FOR were developed for the comparative evaluation of the performance characteristics in terms of contrast (C), contrast-to-noise ratio (CNR) and figure-of-merit (FOM = CNR 2 /DOSE) for spectrally equivalent beams transmitted through filter materials referred to as conventional and k-edged. At the same value of operating potential (kVp), results show that spectrally equivalent beam transmitted through conventional filter with higher atomic number ( Z -value) in comparison with that transmitted through conventional filter with lower Z -value resulted in the same value of C and FOM. However, in comparison with the spectrally equivalent beam transmitted through filter of lower Z -value, the beam through filter of higher Z -value produced higher value of CNR and DOSE at equal tube loading (mAs) and kVp. Under the condition of equivalence of spectrum, at scaled (or reduced) tube loading and same kVp, filter materials of higher Z -values can produce the same values of C, CNR, DOSE and FOM as filter materials of lower Z -value. Unlike the case of comparison of spectrally equivalent beam transmitted through one conventional filter and that through another conventional filter, it is not possible to derive simple mathematical formulations for the relative performance of spectrally equivalent beam transmitted through a given conventional filter material and that through k-edge filter material.

Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)

 Article Access Statistics
    PDF Downloaded270    
    Comments [Add]    

Recommend this journal