A Study on Novel Scintillators for Interventional Multimodal X-ray and Scintigraphy Imaging

Le résumé fourni par la source

Multimodal imaging systems are beneficial for the treatment of cancer with radionuclides, because they provide anatomical and nuclear information at the same time. With the combination of scintigraphy and fluoroscopic X-ray imaging, the hospital logistics and patient burden of e.g. radioembolization procedures could be reduced. One approach is to mount the gamma camera directly behind a flat-panel X-ray detector on a clinical C-arm. A compact design and a naturally good image alignment is obtained. However, several shortcomings still need to be addressed, especially the X-ray induced blinding effects in the gamma camera. To this day, most clinical gamma cameras use NaI(Tl) as the scintillator. NaI(Tl) has a relatively high afterglow, which gives rise to a background signal following each X-ray pulse. This high background obscures the signals generated by the gamma photons emitted by the radionuclide. This research focuses on finding a scintillator with similar properties as NaI(Tl), but with lower afterglow. GATE simulations of the interventional X-ray and scintigraphy imaging detector (IXSI) were performed. The most promising candidates were further studied in our lab. The selection was done using the simulated signal-to-background ratio at 100 ms after the X-ray pulse. For the in-lab measurements, afterglow, energy-resolution, non-proportionality and light yield were evaluated. Initial measurements are consistent with our simulation. The study includes novel compounds like NaI(Tl,Sr), CsI(Tl,Sb,Bi) and the most promising low-afterglow candidate so far, NaI(Tl,Sr,Y).

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.