1. Prof. Stefaan Vandenberghe Enrico Clementel
MEDISIP
Prof. Stefaan Vandenberghe
Enrico Clementel

2. NEUROLOGY EEG MR NEUROLOGY UROLOGY NUCLEAR MEDICINE ONCOLOGY NEUROLOGY
Spike detection
NEUROLOGY
EEG
Artefact removal
Dipole localisation MR
Reconstruction
Spectroscopy
Diffusion imaging
NEUROLOGY
UROLOGY
NUCLEAR
MEDICINE
Reconstruction
Hardware
Simulations
ONCOLOGY
NEUROLOGY
CARDIOLOGY
– Medical Genetics meeting – 4/7/2007

3. Related expertise for this project build up in other projects
– Medical Genetics meeting – 4/7/2007

4. Monte Carlo simulations
Medisip-UGent: OpenGate collaboratie ( > 30 universities), simulation code based on GEANT4
Accurate simulation source, object, PET/SPECT system
Belang
Development of new prototypes
Study of image degrading effects
– Medical Genetics meeting – 4/7/2007

5. Monte Carlo simulations: Image reconstruction
The final main track is image reconstruction. We provide state-of-the-art image reconstruction packages for SPECT and PET. Mainly also using Monte Carlo simulated system matrices. This is important for quantification, dosimetry, and radionuclide therapy.
– MIT – 8/10/2007
– Medical Genetics meeting – 4/7/2007 5 5

6. Hyperimage: simulation of PET/MR test systems
Build-up of a PET system based on modular detector approach of WP1
PET-Detector simulation
System design and development
PET-compatible animal and whole body RF coils and RF shielding
Minimization of the interference between the two modalities, to facilitate simultaneous image acquisition

7. Hyperimage: Novel Algorithms for Motion and Attenuation Correction
Improvement of the PET image quality by using concurrently acquired MR image data for patient motion correction
Integration of motion correction with the acquisition of complementary functional information from PET and MR
Investigation of robust PET attenuation correction methods based on MR data
Development of data analysis and visualization for multidimensional PET/MR data

8. PET systems with better image quality
DT = 500 ps
~ 7.5 cm
DT = 4 ns
non-TOF
TOF CT
– Medical Genetics meeting – 4/7/2007

9. Commercial system (collaboration with Karp/Surti UPENN)
PET scanner
LYSO : 4 x 4 x 22 mm3
28,338 crystals, 420 PMTs
70-cm bore, 18-cm axial FOV
CT scanner
Brilliance 16-slice
Philips Gemini TF
Energy resolution: 11.5% fwhm, Timing resolution: 585 ps
NEMA NU-2
Spatial resolution: 4.8 mm at 1cm
Sensitivity: 6.6 cps/kBq
Scatter fraction at 440 keV: 27% for 20-cm x 70-cm
Peak NEC: mCi/ml

10. Fast reconstruction with SSRB-TOF
this term adds a TOF based correction
to Single Slice ReBinning (SSRB)
FORE-TOF also possible: Michel Defrise, PMB 2005

11. 20 mm spheres 10 mm spheres SSRB-TOF (424 ps) 3D listmode SSRB-TOF
1. Introduction
2. TOF-PET
3. TOF reconstruction
4. Image quality gain
5. Conclusions
SSRB-TOF
20 mm spheres
SSRB
10 mm spheres
3D listmode
SSRB-TOF
SSRB
25 cm

12. SSRB-TOF:axial resolution loss
1. Introduction
2. TOF-PET
3. TOF reconstruction
4. Image quality gain
5. Conclusions

13. determine position in histoprojection
Mashing
Mashing =
Reducing number of
projection angles
by combining
close LORs
1. Introduction
2. TOF-PET
3. TOF reconstruction
4. Image quality gain
5. Conclusions
TOF-Mashing
makes use of the
most likely point to
determine position in histoprojection
*Fast reconstruction of 3D TOF PET data by axial rebinning and transverse mashing S.Vandenberghe et al., Phys. Med. Biol. 51 No ,

14. Filtered Backprojection of PET-data
Mashing
20 angles
Filtered Backprojection of
PET-data
40 angles
1. Introduction
2. TOF-PET
3. TOF reconstruction
4. Image quality gain
5. Conclusions
Confidence Weighted Backprojection of TOF PET 300 ps = 45 mm
5 angles
8 angles
3 angles

15. kernel truncation (used for speedup recon)

16. steven.staelens@ugent.be – Medical Genetics meeting – 4/7/2007

17. TOF resolution depends on countrate !
Clinical range
Measurements Ugent-UCL

18. Correct TOF resolution needed for correct recon !
Phantom
Simulations Ugent, presented at IEEE MIC 2007

20. steven.staelens@ugent.be – Medical Genetics meeting – 4/7/2007

21. Proposal of Ugent tasks in Envision
Simulations of best geometry (limited angle or axially tilted) Corrections in software (time offsets, poster Enrico Clementel) Reconstruction of limited angle data (system matrix based) Physics PhD candidate from US interested for Envision
– Medical Genetics meeting – 4/7/2007