article_image os_neuro1 Anatomický obraz melanomablue Positron Emission Tomography MR Scan (or CT) [USEMAP] n 4DPET_sm 4D-PET-CT_sm melanomablue os_neuro1 article_image MR, CT Anatomie funkce PET/CT [USEMAP] Funkční obrazení Glucose + Isotope (e+) Injection(~2-5mCi) Scan (15-30 minutes) \begin{figure} \centering\leavevmode \hfill \psfig{figure=alb13/Fig15-s.ps,width=3.4in}\hfill\end{figure} [USEMAP] Co je PET? •Isotope production CYCLOTRONS •Tracer production CHEMISTRY SYSTEMS •Imaging SCANNER RW3qtrRsmall [USEMAP] Fyzikální princip n b+ b- ~1-3mm 511KeV 511KeV • Pozitronová dráha 1-3 mm před annihilací (závisí na energii) • Zachování energie a momentu - 511 keV fotony a • Simultánní detekce dvou 511KeV fotonů - výsledek je přímka a současný přichod img004 [USEMAP] n img005 [USEMAP] img007 img006 [USEMAP] n img008 [USEMAP] n img010 [USEMAP] n img013 [USEMAP] Projection Data Collection R PMT PMT COINCIDENCE PROCESSING DETECTOR RING Processing Electronics Processing Electronics Coincidence Processor Data Sorting, Histogram Image Recon Computer Images Basic Principles [USEMAP] DetectorRing RW3qtrRsmall [USEMAP] ex_ani PET Image My Objective è New and better detector design using GEANT4 è Better information to Physicians è Better patient care and treatment [USEMAP] lobe Intra-pulmonary lesion PET-CT fusion localizes PET-CT trauma-r [USEMAP] nPrvní srdce má mykardální infarkt. Šipky ukazují poškozené oblasti (‘smrt tkáně). nDruhé srdce je normální Příklad : Myokardiální nekrózy heart [USEMAP] nPrvní obraz ukazuje maligní nádor, který nebyl diagnostikován běžnými zobrazovacími technikami. (CT, MRI, mammogram) nDruhý obraz již bohužel meta postižení. Příklad: rakovina prsu cancer [USEMAP] Fyzikální princip n b+ b- ~1-3mm 511KeV 511KeV • Simultánní detekce dvou 511KeV fotonů img004 RW3qtrRsmall DetectorRing 18F FDG ( 18F labeled fluorodeoxyglukoza ) PET/CT [USEMAP] image002 n A6MED69 PET-CT2 [USEMAP] Žaludek karcinom [USEMAP] Pankreas - karcinom [USEMAP] Activity A = DN/Dt [s-1] A - activity DN - mean number of radioactive decays Dt - time interval 1 s-1 = 1 Bq (Becquerel) 1 Ci (Curie) = 3.7 x 1010 Bq [USEMAP] Dose D = De/Dm [J.kg-1] D - dose De - mean energy deposited by ionizing radiation to given material Dm - mass of material 1 J.kg-1 = 1 Gy (Gray) 1 rad = 0.01 Gy [USEMAP] Basic principles of radiosurgery The first prototype of the Leksell Gamma Knife was installed in 1968 at Sophiahemmet in Stockholm, Sweden. [USEMAP] Diagram for the decay of 60Co nucleus [USEMAP] Photon depth dose curves [USEMAP] Basic principle of radiosurgery [USEMAP] Dose profiles for the Leksell gamma knife [USEMAP] Physical and technical principles Radiation source: gamma rays from 60Co No. of sources: 201 Collimators: 4, 8, 14, 18, mm Stereotactic target localization: preferably MRI, CT not necessary, angiography Leksell gamma knife [USEMAP] Physical and technical principles Leksell gamma knife [USEMAP] Physical and technical principles Leksell gamma knife 6-LGK_modelC [USEMAP] Physical and technical principles Leksell gamma knife [USEMAP] Physical and technical principles Leksell gamma knife [USEMAP] Physical and technical principles Leksell gamma knife [USEMAP] P7020717 P7020718 P7020716 P7020719 Physical and technical principles Leksell gamma knife 4 mm 8 mm 14 mm 18 mm 14 mm 14 mm 8 mm 8 mm 8 mm 8 mm 4 mm 4 mm [USEMAP] Physical and technical principles Leksell gamma knife [USEMAP] Physical and technical principles Linac radiosurgery or radiotherapy (BrainLAB system) [USEMAP] Physical and technical principles Linac radiosurgery or radiotherapy (BrainLAB system) [USEMAP] Physical and technical principles Linac radiosurgery or radiotherapy (BrainLAB system) [USEMAP] Physical and technical principles Linac radiosurgery or radiotherapy (BrainLAB system) [USEMAP] Clinical applications-acoustic neuroma 3 years after LGK irradiation during LGK irradiation [USEMAP] Clinical applications-metastasis 6 years after LGK irradiation during LGK irradiation [USEMAP] [USEMAP] [USEMAP]