Page 43 - 1. kongres program

ving the quality of SPECT have recently become available. These products incorporate sophisticated corrections for scatter and spatial resolution along with noise suppressi- on. This has provided improved spatial resolution with an increased signal-to-noise ra- tio (SNR). Vendors are using the improved image quality to reduce the acquisition time for myocardial perfusion and other SPECT studies by a factor of two. Statistically-based iterative algorithms in PET became feasible with clinically-acceptable reconstruction times and have replaced the 3D FBP. The iterative OSEM algorithm was used initially has been improved. Reconstruction incorporating the PSF is termed High Definition PET or HD∙PET, results in improved intrinsic resolution and uniformity throughout the FOV. HD·PET incorporates millions of accurately measured point spread functions in the reconstruction algorithms, which dramatically reduces blurring and distortion in the image. Ultra HD PET combining HD PET and TOF. The reintroduction of TOF PET results in a further improvement in SNR. Reconstructions algorithm needs to impro- ve: random correct, attenuation correct, scatter correct, model detector performance especially parallax errors and manage motion, detecting small lesions in high-activity background, provide excellent spatial resolution and high contrast. The second part presented are the major benefits and drawbacks of hybrid-imaging devices, a short overview of the radiation dose to which the patient is exposed in the different devices and the diagnostic outcome. In this part also, a comparison to single modality devices is given, including two single acquisitions on two devices for retrospective hybrid ima- ging (Image Fusion). The last part presented are clinical case studies. Here, the major part is also a comparison of single modalities to hybrid imaging. In this part, the presen- ted benefits and drawbacks will be shown on examples of real clinical patients in the daily workflow. The purpose of development and improvements in nuclear medicine are increase SPECT in PET efficiency, improve spatial resolution, better TOF performance in PET, better detector performance and improve handling organ motion effect. E-pošta: sebastijan.rep@guest.arnes.si 41