Quality Control Procedures for a Whole-Body Counter

Abstract

Variations in design and laboratory use of a whole-body counting instrument require instrument-specific procedures for quality control and maintenance. The whole-body counter at the Mayo Clinic is a low-level counting facility used primarily for determination of total-body potassium and studies of single isotope retention. Maintenance and quality control procedures of this instrument include: (A) daily controls and efforts to maintain a low and constant background counting rate; (B) monitoring the sensitivity and linear response of the detection system by matching photomultiplier tube response; and (C) performance evaluation, such as evaluation of reproducibility and accuracy of measurements. The procedure for counting total-body potassium in a human subject is described in detail.