BJR
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS

British Journal of Radiology (2005) 78, 810-815
© 2005 British Institute of Radiology
doi: 10.1259/bjr/74823655

This Article
Right arrow Abstract Freely available
Right arrow Full Text
Right arrow Full Text (PDF)
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Poletti, J L
Right arrow Articles by Mclean, D
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Poletti, J L
Right arrow Articles by Mclean, D

The effect of source to image-receptor distance on effective dose for some common X-ray projections

J L Poletti, MSc 1,2 and D Mclean, PhD 2,3

1 Unitec New Zealand, Private Bag 92025, Auckland, New Zealand, 2 School of Medical Radiation Science, Cumberland Campus, University of Sydney and 3 Medical Physics Department, Westmead Hospital, Sydney, Australia



View larger version (35K):

[in a new window]
 
Figure 1. The three cases considered by Welander and Wickman, collimation to (a) image receptor, (b) central region of interest (ROI) and (c) entrance surface. The arrows indicate the size and position of the beam area.

 


View larger version (17K):

[in a new window]
 
Figure 2. Theoretical normalized energy imparted as source-to-image distance (SID) is changed, for collimation to image receptor, central region of interest (ROI) and entrance surface.

 


View larger version (11K):

[in a new window]
 
Figure 3. (a) Dependence of effective dose on source to image distance (SID) for the lateral chest projection for three collimation cases. (b) Dependence of effective dose on SID for the lateral lumbar-spinal joint (LSJ) projection for extended SID up to 10.0 m. Collimation is to a central ROI. The line of best fit is for SID of 2.0–10.0 m.

 


View larger version (33K):

[in a new window]
 
Figure 4. Collimation to a fixed beam size at the entrance surface, showing the cut-off of tissue at greater source-to-image distances (SIDs). In practice, if the SID is increased, the light-field dimensions have to be increased also so as to avoid this cut-off.

 





HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
BJR DMFR IMAGING  ALL BIR JOURNALS 
Copyright © 2005 by the British Institute of Radiology.