RT Journal Article SR Electronic T1 Can the Injected Dose Be Reduced in 68Ga-PSMA-11 PET/CT While Maintaining High Image Quality for Lesion Detection? JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 189 OP 193 DO 10.2967/jnumed.119.227207 VO 61 IS 2 A1 Isabel Rauscher A1 Wolfgang P. Fendler A1 Thomas A. Hope A1 Andrew Quon A1 Stephan G. Nekolla A1 Jeremie Calais A1 Antonia Richter A1 Bernhard Haller A1 Ken Herrmann A1 Wolfgang A. Weber A1 Johannes Czernin A1 Matthias Eiber YR 2020 UL http://jnm.snmjournals.org/content/61/2/189.abstract AB Our purpose was to define a clinically useful lower limit of injected dose for 68Ga-prostate-specific membrane antigen (PSMA)-11 PET/CT imaging of prostate cancer. Methods: 68Ga-PSMA-11 PET/CT was performed on 11 patients. PET was acquired in list mode and reconstructed using a 3-min full acquisition, a 2-min acquisition, and a 1-min acquisition to generate images obtained with three thirds (standard dose), two thirds (low dose), and one third (very low dose) of the injected dose, respectively. Overall image quality (5-point scale) was assessed, and the detectability of PSMA-positive lesions was determined by 3 readers and compared with the reference standard. Results: Image quality declined with decreasing dose (mean score of 4.1 ± 0.4 for the standard dose, 3.4 ± 0.7 for the low dose, and 1.9 ± 0.4 for the very low dose; all P < 0.05). Readers 1, 2, and 3 correctly identified the lesions (n = 21) at a rate of 100%, 100%, and 95% with the standard dose; 95%, 81%, and 90% with the low dose; and 71%, 76%, and 59% with the very low dose, respectively. Conclusion: 68Ga-PSMA-11 dose reduction is not feasible without a negative impact on image quality and lesion detectability.