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Workshop Summary Workshop Summary Anthony Butler Radiologist and Physicist Disclaimer I have many biases - I am a clinician by job and physicist by hobby - My university has been a member of Medipix since 2006 - I am a founder of MARS Bioimaging Ltd Overview Participants and submissions Context Review of talks Conclusions Disclaimer NZ has a strange view of the world Disclaimer NZ has a strange view of the world Participants Context Review of talks Conclusions Scientific committee Michael Campbell, CERN Anthony Butler, Univ. of Canterbury & MARS Bioimaging Steffen Kappler, Siemens Healthineers Ewald Roessl, Philips Research Laboratories Katsuyuki (Ken) Taguchi, Johns Hopkins University Richard Thompson, Canon Medical Research Brian Yanoff, GE Global Research … with lots of assistance from Patricia Mage-Granados Initiation only for several reasons Participants 119 registrants 2017 => 130 2013 => 102 2015 => 112 2011 => 76 50 Industry; 46 Scientists; 23 Medical >85% are returning guests Participants and submissions Context Review of talks Conclusions Context The electromagnetic spectrum X-ray colour: Wavelength, Frequency, or Energy Context Spectral CT is true colour x-ray imaging Context Hounsfield, Nobel Prize 1979 Computed Tomography is 3D X-rays Context 300,000,000 people per year get a CT Hounsfield, Nobel Prize 1979 Computed Tomography is 3D X-rays Context Rontgen 1895, to CERN technology 2018 Context Before SpecXray Earnest Rutherford: We have no money, therefore we must think Particle physics pushes frontiers of knowledge Context Before SpecXray Early ’80s, direct Si detectors – Erik Heijne, Robert Klanner, Gehard Lutz Their role is recognized by the 2017 High Energy and Particle Physics Prize of EPS Mid ’90s, Medipix – Michael Campbell “Various applications like Medical Imaging should profit” Context SpecXray 2011 Mouse, Mouse, Human, Anthony Butler Ewald Roessel Jerry Arenson MARS, Philips, and GE Healthcare Context 2011 to 2019 PCD 2017 2011 Rajiv Gupta, Mass.Gen.Hosp Context 2011 to 2019 PCD 2017 2011 2013-2017 Rajiv Gupta, Mass.Gen.Hosp Context 2011 to 2019 PCD 2017 2011 2013-2017 2019 Rajiv Gupta, Mass.Gen.Hosp Context The world has changed More focus on value, not excellence … … scanners for emerging markets … United Imaging Ltd … health-pathways and efficient care Radiology market has changed Context The world has changed More focus on value, not excellence … … scanners for emerging markets … United Imaging Ltd … health-pathways and efficient care Earlier decision making… … growth of Urgent and Point-of-Care … Artificial Intelligence Radiology market has changed I’m lucky if I can learn one thing per talk Participants Context Review of talks Conclusions Invited talk A patient in Tuba City, Arizona (Navajo Nation), 5hr drive from Albuquerque Scanners with no moving parts in order to meet the community’s needs Re-imagining the imaging system Rajiv Gupta, Mass.Gen.Hosp Invited talk Image processing is a critical part of the system Reimaging the imaging system Rajiv Gupta, Mass.Gen.Hosp Taking it to humans The world is watching Anthony Butler, Uni. Of Canterbury Taking it to humans Imaging where the clinician wants to see Universal protocols practical for users Strong focus on clinical benefits Cynthia McCollough, Mayo Clinic Clinical applications PCD EID Multiple image metrics showing PCD gives better image quality Photon counting gives better image quality Jayasai Rajagopol, NIH Clinical Centre Clinical applications Image quality = Can I make a diagnosis? Need to assist clinicians Thorsten Fleiter, Uni. of Maryland Clinical applications Iodine and Bismuth used simultaneously ( animal models of tumors ) Multiple contrast agents for radiological surgery William Pritchard, NIH Clinical Centre Clinical applications Structure and mineralization Gout Micro-fractures Lots of easily accessible bone applications Aamir Raja, Uni. of Otago Prototype systems Building systems is hard! Showed complexity of systems Pete Edic, GE Global Research Prototype systems Protocols vary, but potentially big dose advantages PCT allows high resolution and low dose Shuai Leng, Mayo Clinic Prototype systems 2 sources + 2 bin detectors = 4 energies Number of bins and energy separation is critical Shuai Leng, Mayo Clinic Detector systems Gd/Ho K-edges: 6 keV apart Very close materials can be separated Magdalena Bazalova-Carter, Uni. of Victoria Detector systems 1 mm CdTe Internal Escape XRF peak Improved spectral resolution Improved spatial resolution Timepix3 is a REALLY advanced detector Jan Jakubek, ADVACAM Detector systems Singe chip Compton camera for thyroid Jan Jakubek, ADVACAM Detector systems 4 side buttable, 5 energy, high flux Kris also talked about who might benefit from spectral imaging CZT and commercial detectors have improved Kris Iniewski, Redlen Technologies Lots of time for discussion Coppet and its chateau Thanks to Michael and Patricia Detector modelling Charge transport over time Yi Qiang, Cannon Medical Research Simulations and Recon …. may be enough to get good images Just measure co-incident, but don’t correct Scott Hsieh, UCLA Simulations and Recon Spectral phase contrast – an important future Thorsten Sellerer, Technical Uni. Munich Simulations and Recon What is the optimal basis for describing tissues? Spectra -> Eigen-basis -> Materials Eigen-tissue decomposition Mikael Simard, Uni. of Montreal Detectors of HEP Very clear description of LHC, ATLAS, and CMS Walter Snoeys, CERN Molecular imaging Two contrast agents - tumor vascularization - nano-particle distribution Nano-particles are used in cancer research Ananth Annapragada, Baylor College Molecular imaging Ex-vivo imaging means he knows what he wants to see in humans Cardiovascular disease causes 37% of EU deaths Steven Gieseg, Uni. Canterbury Material Decomposition Improvements in projection based MD Artur Sossin, Philips Innovative Technology Material Decomposition More flexible: - apply image constrains - variable energy bins - non-ideal detectors - flux dependent effects - variable input spectra Projections Materials One step reconstruction and MD Taly Schmidt, Marquette Uni. High-Z semi-conductors Instability more noticeable at high energy thresholds Th1 Th2 Th3 Th4 Th5 Stability counts >200 Mcps/mm2 Integrated achievable! High photon flux is a challenge Georgios Prekas, Redlen Technology ASICs Excellent for pushing the limits of spectral x-ray technology 65nm technology Pixel matrix of 512 x 448 pixels (55 µm x 55 µm) Particle identification and tracking (Data driven) Imaging (frame based with CRW sequential readout) Sub-ns time binning ~195ps Max data output ≤163.84 Gbps Energy resolution <1 KeV 4 side buttable due to TSV Timepix4 is almost here Xavi Llopart, CERN ASICs Increase detector area for real clinical CTs TSV New 4 side buttable ASIC for CT Edgar Goederer, Siemens Healthineers ASICs Increase detector area for real clinical CTs New 4 side buttable ASIC for CT Edgar Goederer, Siemens Healthineers ASICs Charging sharing and pulse pile-up are the main challenges Charge sharing correction scheme Pawl Grybos, AGH Uni.of Science and Technology ASICs Want to have: charge sharing correction, pile-up correction, more energies Currently: Future: 2 energies Pile-up rejection Charge sharing correction 256 energy bins-real time 2 side “buttable” Energy resolution 7 to 9% OCR= 8 Mcps/pixel https://ctcicblog.mayo.edu/hubca https://www.nih.gov/news-events/news-releases/nih-uses-photon-counting-ct-scanner-patients-first-time p/our-scanners/ Moving beyond 2 energies for clinical CT Loick Verger, CEA LETI ASICs My favorite talk ! A great review of competing requirements Rafael Ballabriga, CERN Participants Context Review of talks Conclusions Conclusion “This is what happens when you bring people with good ideas together to form a community” Stephan Kappler, Scientific committee Conclusion Looking back what have we learned since 2011? The medical applications of spectral x-ray detectors are: - new information - higher resolution - lower dose Conclusion Looking back what have we learned since 2011? The medical applications of spectral x-ray detectors are: - new information - higher resolution - lower dose 2011 – would any of this work? Conclusion What have we learned in this workshop? Spectral CT is going to happen - all of the challenges are successfully being address - it will reach the clinics (timelines remain uncertain) At least 300,000,000 people per year will benefit Thanks you Michael Campbell, CERN Anthony Butler, Univ. of Canterbury & MARS Bioimaging Steffen Kappler, Siemens Healthineers Ewald Roessl, Philips Research Laboratories Katsuyuki (Ken) Taguchi, Johns Hopkins University Richard Thompson, Canon Medical Research Brian Yanoff, GE Global Research .
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