Gamma Counters in Nuclear Medicine-Design and Operation

This tutorial, with quiz; is ideal for a Board Certified Nuclear Pharmacist wishing to earn 2 CEU credit.

Proceed to the Tutorial: Gamma Counters in Nuclear Medicine Tutorial

Proceed to the Quiz: Gamma Counter Quiz

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This tutorial gives an overview on Attenuation of Radiation

  1. Summary:This tutorial provides an overview of methods employed for counting gamma ray emissions; discusses the sensitivity of each method; describes the components of a gamma counter; explains what a pulse height analyzer is; describes the spectrum produced and how to identify radioisotopes; discusses energy resolution and the Full Width Half Maximum calculation; explains  how to set energy windows; defines dead time and its impact on counting of samples; lists different types of counting equipment used for gamma ray detection and quantification; and lists the factors affecting detector efficiency.Objectives:At the conclusion of this tutorial, one should be able to:
    1. Describe generalized methods of gamma ray detection;
    2. List the major components of a well-counter and the importance of the NaI(Tl) crystal, the photomultiplier tube, and other components;
    3. Explain how to identify an unknown radioisotope based on its gamma ray spectrum;
    4. Identify the X-ray peak, the backscatter peak, the Compton Edge, and the photopeak in a gamma ray spectrum
    5. Write the formula for calculation of FWHM Energy Resolution of a NaI(Tl) crystal
    6. Explain how to set a window around the photopeak of an isotope;
    7. Define dead time and the problems caused if the value is too high;
    8. Explain the utility and operation of a well counter and a thyroid uptake probe

If you have taken one of the tutorials, received a score of 80% or above, and wish to receive CE credit: Make sure you submit all of the requested information when taking the test. It’s not necessary to send us the score sheets since we receive them electronically when you submit your answers for scoring.

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    If you have any problems with the self-reporting system, please contact the VOICE Coordinator directly at 703 708-9000. ).

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