Retrospective SPECT/CT dosimetry following transarterial radioembolization

Transarterial radioembolization (TARE) effectively treats unresectable primary and metastatic liver tumors through intra-arterial injection of Yttrium-90 (90Y) beta particle emitting microspheres which implant around the tumor. Current dosimetry models are highly simplistic there is a large need for an image-based post-TARE, would improve treatment safety efficacy. post-TARE imaging 90Y bremsstrahlung SPECT/CT we study use these images dosimetry. Retrospective image review ten patients having Philips HealthcareTM following TARE SIR-Spheres® implantation. Emission series with attenuation correction were resampled to 3 mm resolution used create dose distributions. Dose distributions analysis performed in MIM Software SurePlanTM utilizing Local Deposition Method (LDM) convolution method (WFBH). We sought implement patient-specific background subtraction prior calculation make noisy SPECT suitable On average percentage mean counts maximum count across all was 9.4 ± 4.9% (maximum = 7.6%, minimum 2.3%). Absolute increased profile line width decreased as value increased. The LDM WFBH methods statistically same. As increased, DVH curves become unrealistic distorted. Background on has effect contour defined provides systematic estimate activity that accounts scanner patient conditions at time easily implemented using commercially available software. Using entire gave most realistic This methodology independent microsphere software manufacturer allowing any products or tools.