Comparison of 90Y and 177Lu measurement capability in UK and European hospitals

•90Y and 177Lu measurement accuracy in UK and European hospitals is presented.•40% of participants are able to measure 90Y to within 5%.•81% of participants are able to measure 177Lu to within 5%.•Geometry dependence is identified in radionuclide calibrator measurements of 90Y.

Comparison exercises involving 90Y and 177Lu were performed during 2009 and 2012, respectively, to assess the measurement capability of hospitals in the UK and Europe. The results from the measurement of a typical liquid solution of 90Y show that only 40% of participants could measure the solution to within 5% of the certificated value and that a significant −6% bias was present due to the use of non-standard geometries for the calibration of equipment. The results from the measurement of a standard liquid solution of 177Lu show that 81% of participants could measure to within 5% of the certificated value and in fact 65% of these results were within 2% of the certificated value, showing administered activities can be far more accurately measured for 177Lu than for 90Y and that 177Lu has a far smaller geometry dependence. These studies were performed to identify specific measurement issues in the user community and to identify areas where future research should be focused. In addition to this the work allows the participants to adjust measurement practice and identify key measurement issues.