The value of yttrium-90 PET/CT after hepatic radioembolization: a pictorial essay

Introduction Distribution of microspheres after radioembolization can be accurately visualized using PET/CT. In this pictorial essay, we aim to demonstrate the value of 90 Y-PET/CT after radioembolization. Methods 90 Y-PET/CT imaging was routinely performed after radioembolization at our institute. Patients were scanned the same day or the day after treatment, using a scanner with time-of-flight technology. We retrospectively reviewed all 90 Y-PET/CTs from patients treated with radioembolization (both glass and resin microspheres) between January 2011 and January 2019. Five cases were selected that are illustrative of the added value of PET/CT after radioembolization. Results 90 Y-PET/CT allows for distribution assessment and dosimetry of 90 Y-microspheres. It was used for the assessment of treatment success by visualization of tumor targeting, quantification of the absorbed dose, prediction of complications such as radioembolization-induced liver disease, and determining the required dosage for retreatment. Conclusion PET/CT is an excellent modality for post-treatment imaging of 90 Y-microspheres and could lead to improved dose planning and more personalized treatment.