99mTc-MAA/90Y-Bremsstrahlung SPECT/CT after simultaneous Tc-MAA/90Y-microsphere injection for immediate treatment monitoring and further therapy planning for radioembolization

Abstract

Combining RE and Re-MAA is feasible in appropriately selected patients.

90Y PET-based dosimetry after selective internal radiotherapy treatments

“…At present, biodistribution of 90 Y after treatment is generally assessed through Bremsstrahlung SPECT [12] or 99m Tc SPECT [13] images if during therapy MAA particles are administered after microsphere injection. Nevertheless, both techniques present important drawbacks.…”

Theranostic Imaging of Yttrium-90

“…The radioembolized left renal mass and bilateral lungs demonstrated 90 Y radioactivity on posttherapy bremsstrahlung imaging and the bilateral lung radioactivity was presumed arteriovenous shunting of microspheres through the tumor and then trapped in the lungs. Subsequently, others have described posttherapy planar bremsstrahlung imaging for patients following direct injection of 90 Y (e.g., radiosynovectomy) [5, 6], intravenous administration of 90 Y-labeled RIT [26], and intra-arterial administration of 90 Y-labeled microspheres [27–31]. In addition, one study demonstrated the capability for planar bremsstrahlung imaging to detect focal 90 Y radioactivity using a phantom model simulating soft tissue extravasation of an intravenous 90 Y dose [32].…”

“…Subsequently several other clinical studies have described posttherapy SPECT and/or SPECT/CT bremsstrahlung imaging for patients following direct injection of 90 Y [47], intravenous administration of 90 Y-labeled RIT [2, 26] and PRRT [47], and intra-arterial administration of 90 Y-labeled microspheres (resin [14, 29–31, 44, 48–59], glass [54, 60–63], or not specified [64]). Table 1 lists the previously reported image acquisition settings used for clinical 90 Y bremsstrahlung planar and SPECT imaging.…”

From the Angio Suite to the γ-Camera: Vascular Mapping and 99mTc-MAA Hepatic Perfusion Imaging Before Liver Radioembolization—A Comprehensive Pictorial Review

“…A medium-energy collimator, instead of a low-energy all-purpose collimator, will optimize imaging of the 140-keV photons of 99m Tc-MAA by eliminating most of the higher-energy photons of the bremsstrahlung radiation. A low-energy high-resolution collimator can also be used (31). Narrowing the energy window to 10% will further reduce the amount of scattered bremsstrahlung photons reaching the detectors.…”