225Ac-based PSMA-targeted therapy has emerged as promising agent for the treatment of metastatic castration-resistant prostate cancer. Posttherapy image is used for tracer localization and dosimetry. Prior 2 photopeaks of 440 and 218 KeV were reported for posttherapy imaging. Our study of gamma ray spectrum, phantom, and clinical images show that imaging with 3 major photopeaks of 78, 218, and 440 KeV gives better quality images, high count statistics, and higher number of lesion delineations. It is therefore suggested that posttherapy imaging may be carried out using 3 major abundant photopeaks.
From the *Kuwait Cancer Control Centre (KCCC), Kuwait City, Kuwait;
†Government College University, Faisalabad, Pakistan; and
‡Jaber Al-Ahmad Centre for Nuclear Medicine and Molecular Imaging, Kuwait City, Kuwait.
Received for publication October 11, 2018; revision accepted January 25, 2019.
Conflicts of interest and sources of funding: none declared.
Correspondence to: Rashid Rasheed, MS, MBBS, Department of Chemistry, New Campus, Sir Syed Block, Government College University, 38000, Faisalabad, Pakistan. E-mail: firstname.lastname@example.org.