Children may get too much radiation in CT scan

["Sandy Perle" <sandyfl@earthlink.net>]

My personal observations:

(1) There is not one mention of any actual dose values. This 
information would be helpful to put some of the many insinuations 
into perspective.

(2) The term "overdoses" always irks me. Since medical radiation 
exposure is basically not regulated, are these researchers taking 
license in comparing the CT scan dose to the permissible dose to 
minors, as found in 10CFR20? A minor is permitted to receive 500 
mrem/year (5.00 mSv/year). Is any dose  above this value what 
they deem to be an over-exposure?

(3) 500 cancer deaths a year? Any scientific studies to validate 
these claims?  How many of these children already have cancer, 
or, are in a pre-cancerous condition, which is only detected after 
the scan, and then the assumption si that the scan is the 
causative factor?

Comments on the article would be appreciated.
--------------

Children may get too much radiation in CT scan

WASHINGTON, Jan 22 (Reuters) - Children who get CT scans -- a 
kind of X-ray that can be used to make a more three-dimensional 
image of the body -- may be getting overdoses of radiation, 
researchers said on Monday. 

And up to 500 children a year in the United States alone could die 
from cancer because of it, a second team of researchers said. 

Some children who get computed tomography (CT) scans are 
getting doses at least five times greater than necessary, Dr. Lane 
Donnelly at Cincinnati Children's Hospital Medical Center and 
colleagues found. X-rays and similar forms of radiation can cause 
cancer. 

This could add up to extra cases of cancer, because so many CT 
scans are done in the United States, Dr. David Brenner and 
colleagues at Columbia University in New York added. 

"The larger doses and increased lifetime radiation risks in children 
produce a sharp increase, relative to adults, in estimates risk from 
CT," Brenner and colleagues wrote on the February edition of the 
American Journal of Roentgenology. 

"In the United States, of approximately 600,000 abdominal and 
head CT examinations annually performed in children under the age 
of 15 years, a rough estimate is that 500 of these individuals might 
ultimately die from cancer attributable to the CT radiation." 

The researchers said radiologists could turn down the X-rays 
without losing quality, and thus expose the children to less 
potentially cancer-causing radiation. 

"CT is often a necessary part of the evaluation of children with 
suspected illness," Donnelly, whose study is published in the 
same journal, said in a statement. 

"The benefit from the information obtained by the CT greatly 
outweighs the radiation risk. However ... it's not only imperative to 
make an accurate diagnosis, but also to strive to make the risks 
as minimal as possible." 

CT is a radiologist's first choice in diagnosing children with 
abdominal pain, suspected appendicitis, abdominal trauma, a 
suspected mass, or complicated pneumonias. 

It is used in about 4 percent of medical X-ray examinations, but it 
contributes to an estimated 40 percent of the total radiation dose to 
the population. 

This is especially true in children because all the guidelines on how 
much radiation to use are based on studies that used adults, said 
Dr. Kathleen Emery, a staff radiologist who worked on the study. 

"It began to bother us that we used parameters based on adult 
studies," she said. "Unlike general radiography, there is no penalty 
for using a higher dose of radiation, whereas in regular X-rays, too 
high a dose would result in a black picture." 
----------------------------------------------------------------------------------
Sandy Perle					Tel:(714) 545-0100 / (800) 548-5100   				    	
Director, Technical				Extension 2306 				     	
ICN Worldwide Dosimetry Service		Fax:(714) 668-3149 	                   		    
ICN Pharmaceuticals, Inc.			E-Mail: sandyfl@earthlink.net 				                           
ICN Plaza, 3300 Hyland Avenue  		E-Mail: sperle@icnpharm.com          	          
Costa Mesa, CA 92626

Personal Website: http://sandyfl.nukeworker.net
ICN Worldwide Dosimetry Website: http://www.dosimetry.com
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