Syringe shape and positioning relative to efficiency volume inside dose calibrators and its role in nuclear medicine quality assurance programs.

A careful analysis of geometry and source positioning influence in the activity measurement outcome of a nuclear medicine dose calibrator is presented for (99m)Tc. The implementation of a quasi-point source apparent activity curve measurement is proposed for an accurate correction of the activity inside several syringes, and compared with a theoretical geometric efficiency model. Additionally, new geometrical parameters are proposed to test and verify the correct positioning of the syringes as part of acceptance testing and quality control procedures.