Improved dose determination for Molecular Radiotherapy Andrew Robinson Dave Cullen Nuclear Physics Group, The University of Manchester Jill Tipping David Hamilton The Christie NHS Foundation Trust
Christie Research Huddle – 07/04/14
Christie Research Huddle – 07/04/14
Scatter Correction Triple Energy Window Sensitivity Factor Christie Research Huddle – 07/04/14
TRT with 177Lu-DOTATATE 177Lu: t1/2 = 6.647 days bbeta (177Lu) = 100% bgamma (177Hf) = 18% EM SC RAW TEW Clinical problem: First figure Attempting to follow course of therapeutic radionuclide over course of several days Range of activities covered several GBq to few hundred MBq WB Hundred to single finger MBq in tumours Signal to background ratios >20:1 to 3:1 Sizes covered WB, organ size eg liver ( 1700ml) , tumour size few 10s of mls Second figure Scatter look at projection in tomogram in energy window, can use scatter window/s to get estimate of scatter in emission ; scatter component can be significant. 5-10-20% and above Figure three can try and correct for scatter. See affect of correction of scatter on tomographic slice Pictures look better, but how does ability to quantify do over all these conditions? 5000 MBq 300 MBq Day 0 Day 6 Christie Research Huddle – 07/04/14
Simulation - Camera Collimator and touch plate Crystal PMT array Back compartment Shielding Bed and mattress Christie Research Huddle – 07/04/14
Simulation - Phantom Christie Research Huddle – 07/04/14
Simulation - Sources 99mTc T1/2 = 6.0 hrs Bgamma = 0.999963 (140 keV) Bbeta = 0.000037 (112 keV mean energy) 177Lu T1/2 = 6.647 days Bgamma = 0.236 (113, 208 keV daughter nucleus) Bbeta = 1.000 (134.2 keV mean energy) 90Y T1/2 = 64.053 hrs Bgamma = 0.000115 (1.76 MeV daughter nucleus) Bbeta = 1.000 (933 keV mean energy) Bpositron = 0.000032 (daughter nucleus)
Simulation - Sources 99mTc T1/2 = 6.0 hrs Bgamma = 0.999963 (140 keV) Bbeta = 0.000037 (112 keV mean energy) 177Lu T1/2 = 6.647 days Bgamma = 0.236 (113, 208 keV daughter nucleus) Bbeta = 1.000 (134.2 keV mean energy) 90Y T1/2 = 64.053 hrs Bgamma = 0.000115 (1.76 MeV daughter nucleus) Bbeta = 1.000 (933 keV mean energy) Bpositron = 0.000032 (daughter nucleus) Bremsstrahlung
Cluster Gate 6.1 Gate 6.2 Gate 7.0(beta) Geant 4.9.4 Geant 4.9.5 Geant 4.10 (MT) Christie Research Huddle – 07/04/14
Cluster 264 cores 76 TB storage nucpc76.ph.man.ac.uk FASTPC2 x2 Xeon E5520 @ 2.27GHz 8 Cores (16 with Hyper Threading) nucpc90.ph.man.ac.uk FASTPC3 x2 Xeon E5620 @ 2.4GHz 8 Cores (16 with Hyper Threading) nucpc91.ph.man.ac.uk FASTPC4 x2 Xeon E5620 @ 2.4GHz 8 Cores (16 with Hyper Threading) 264 cores 76 TB storage nucpc96.ph.man.ac.uk FASTPC5 x2 Xeon E5620 @ 2.4GHz 8 Cores (16 with Hyper Threading) nucpc97.ph.man.ac.uk FASTPC6 x4 AMD Opteron 6176 @ 2.3GHz 48 Cores nucpc108.ph.man.ac.uk FASTPC8 x4 AMD Opteron 6274 @ 2.2GHz 64 Cores nucpc115.ph.man.ac.uk FASTPC9 x4 AMD Opteron 6274 @ 2.2GHz 64 Cores nucpc116.ph.man.ac.uk FASTPC10 x4 AMD Opteron 6274 @ 2.2GHz 64 Cores
Improved Scatter Correction “Is it possible to have a scatter correction method which provides accurate quantification and improved image quality which is applicable in ALL conditions? Quantification Image Quality
Triple Energy Window Correction Infinia Hawkeye Simulation (all events) Unscattered events ICMP 2013 – Brighton (4th September)
Triple Energy Window Correction Infinia Hawkeye Simulation (all events) Unscattered events EM1 EM2 K. Ogawa et al, IEEE Trans. Med. Imaging, 10, 408-412 (1991) Scat
Pre reconstruction TEW Whole Image Christie Research Huddle – 07/04/14
Pre reconstruction TEW Whole Image Christie Research Huddle – 07/04/14
3D Printing Use 3D printing to produce phantom inserts based on CT images. Sensitivity Factor Partial Volume effects Patient specific measurements Christie Research Huddle – 07/04/14
3D Printing Christie Research Huddle – 07/04/14
3D Printing Christie Research Huddle – 07/04/14
3D Printing Christie Research Huddle – 07/04/14