Re: ? renal scan dose

[Richard Smart <R.Smart@unsw.edu.au>]

At 06:14 PM 17.7.97 -0500, you wrote:

>
>My limited nuc med references show a typical dose of 20 mCi, with a post
>administration dose rate of 2 mrem/hour at 3 feet.  If this is correct,
>the badges should show less than 10 mrem.
>


There are a number of possible radiopharmaceuticals that could have been
used, each of which has different kinetics within the body.  The most likely
would be:

Tc99m-DTPA      typical activity 10-15 mCi
Tc-99m-MAG3     typical activity  5-8 mCi
Tc-99m-DMSA     typical activity  2-5 mCi

The dose rate at 1 m will vary markedly with time as both DTPA and MAG3 are
excreted via the urine.

As an example, at 30 min post injection after 10 mCi of Tc-99m,  the dose
rate at 1 m is approx. 5 micro Sv/hr (0.5 mrem/hr).

A useful reference is Mountford PJ et al, Radiation dose rates from adult
patients undergoing nuclear medicine investigations. Nuc. Med.
Communications  1991; 12:767-777

Hope this is useful

Richard Smart

Richard Smart PhD
Department of Nuclear Medicine
St. George Hospital
Kogarah, NSW 2217
Australia
Tel:61 2 9350 3112
Fax:61 2 9350 3991
Email:R.Smart@unsw.edu.au