Re: palladium seeds

["Mike Bohan" <mike.bohan@yale.edu>]

        Reply to:   RE>palladium seeds

Hi Elsa,

Palladium-103 has a half life of 16.97 days and decays by electron capture with
the emission of characteristic x-rays of 20-23 keV and Auger electrons.  There
are also a few high energy photons at 359.6 keV but their probability is only
0.03% per decay.   The half-value layer in lead is 0.008 mm and approx. a cm in
tissue.  The typical activity used for permanent implant is about 1 - 2
mCi/seed.  A typical prostate implant requires about 50 - 100 seeds depending
upon the size of the prostate.  Typical dose rates at 30 cm from the abdomen are
less than 1 mR/hr.

These implants do not pose a radiation hazard to others and we normally instruct
the patient to not allow children to sit directly on their laps for extended
periods for the first few months after implant and to watch for dislodged seeds
which may be excreted through the urinary tract.

For additional information, you might try surfing to:
 
http://www.theragenics.com/

This is the web address for the manufacturer of the seeds.

Hope this answers your questions.
<><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><
Michael J. Bohan, RSO   |  e-mail: mike.bohan@yale.edu
Yale-New Haven Hospital |    Tele: (203) 785-2950
Radiological Physics    |     FAX: (203) 737-4252
20 York St. - WWW 204   |    As usual, everything I say may be plausibly
New Haven, CT    06504  |    denied at my employer's convenience ...
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--------------------------------------
Date: 28/05/97 9:29 AM
To: Mike Bohan
From: radsafe@romulus.ehs.uiuc.edu
A friend will have prostate treatment using surgically implanted
palladium seeds.  

I'm looking for some really basic info -- which isotope, info on
activities typically (?) used, anything on initial dose rates at
patient's skin &  at some greater distance, normal precautions patient
must take after implant.

Anyone know any good references or have time to tell a bit about this,
from a radiation safety perspective? 

Thanks,
Elsa Nimmo

nimmo_elsa@measurex.com