Quantification of Lu-177 on a Cadnium Zinc Telluride Gamma Camera

Abstract

Solid state gamma cameras with Cadmium Zinc Telluride (CZT) detectors provide improved spectral resolution and improved count-rate performance compared to conventional scintillation cameras. This project will explore how these differences influence the accuracy of Lu-177 quantification in post-therapy patient imaging. Monte Carlo methods will be used to model the CZT detector and appropriate sources of Lu-177. The model will be validated against experimental data acquired on a CZT camera. Experimental work on the CZT camera will include basic camera characterisation using sources of Lu-177, according to the NEMA specifications. Phantom studies designed to simulate realistic patient scatter conditions will be conducted. Analysis will be used to determine optimal acquisition and post-processing parameters. The optimised imaging parameters and sensitivity factor calculated will be implemented for patient imaging, in order to calculate the activity within regions of Lu-177 uptake. 10 patients will have quantification carried out on their Lu-177 DOTATATE post-therapy SPECT/CT to calculate the activity within target lesions and organs at risk across their 4 treatment cycles, so that lesion doses can be calculated. Improved quantification accuracy of Lu-177 imaging will allow improved accuracy of dosimetry for Lu-177 DOTATATE and Lu-177 PSMA therapies. This will allow a potential for personalised Lu-177 DOTATATE and PSMA activity prescriptions giving the patient a better chance of the treatment working for them.

Outputs

None – only just started.