Non-Target Activity Detection by Post-Radioembolization Yttrium-90 PET/CT: Image Assessment Technique and Case Examples

Front Oncol. 2014 Feb 3:4:11. doi: 10.3389/fonc.2014.00011. eCollection 2014.


High resolution yttrium-90 ((90)Y) imaging of post-radioembolization microsphere biodistribution may be achieved by conventional positron emission tomography with integrated computed tomography (PET/CT) scanners that have time-of-flight capability. However, reconstructed (90)Y PET/CT images have high background noise, making non-target activity detection technically challenging. This educational article describes our image assessment technique for non-target activity detection by (90)Y PET/CT, which qualitatively overcomes the problem of background noise. We present selected case examples of non-target activity in untargeted liver, stomach, gallbladder, chest wall, and kidney, supported by angiography and (90)Y bremsstrahlung single-photon emission computed tomography with integrated computed tomography (SPECT/CT) or technetium-99m macroaggregated albumin SPECT/CT.

Keywords: SIR-spheres; bremsstrahlung SPECT/CT; diagnostic reporting technique; non-target activity; selective internal radiation therapy; yttrium-90 PET/CT; yttrium-90 radioembolization; yttrium-90 resin microspheres.