IEEE Nuclear Science Symposuim & Medical Imaging Conference最新文献

{"title":"CaF2(Eu): An “Old” scintillator revisited","authors":"C. Plettner, G. Pausch, F. Scherwinski, C. Herbach, R. Lentering, Y. Kong, K. Romer, J. Stein, T. Szczesniak, M. Grodzicka, J. Iwanowska, M. Moszynski","doi":"10.1088/1748-0221/8/06/P06010","DOIUrl":"https://doi.org/10.1088/1748-0221/8/06/P06010","url":null,"abstract":"Homeland security applications demand high performance Compton-camera systems, with high detector efficiency, good nuclide identification and able to operate in-field conditions. A low-Z scintillator has been proposed and studied as a promising candidate for use in the scattering plane of a scintillator-based Compton camera: CaF2(Eu). All the relevant properties for the application of this scintillator in a mobile Compton camera system have been addressed: the energy resolution and the non-linearity at room temperature and in the temperature range of −20°C to +55°C, the photoelectron yield and the relative light yield in the relevant temperature range. A new method of inferring the relative light output of scintillators as a function of temperature has been proposed.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"227 1","pages":"236-242"},"PeriodicalIF":0.0,"publicationDate":"2013-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77468303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the accuracy and robustness of a motion correction algorithm for PET using a novel phantom approach","authors":"S. Wollenweber, Girish Gopalakrishnan, K. Thielemans, R. Manjeshwar","doi":"10.1109/NSSMIC.2010.5874232","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5874232","url":null,"abstract":"We introduce the use of a novel physical phantom to quantify the performance of a motion-correction algorithm. The goal of the study was to assess a PET-PET image registration, the final output of which is a motion-corrected high-statistics PET image volume, a procedure called Reconstruct, Register and Average (RRA). Methods: A phantom was constructed using 5 ∼2mL Ge-68 filled spheres suspended in a water-filled tank via lightweight fishing line and driven by a periodic motion. Comparison of maximum and mean concentration and sphere volume was performed. Ground truth data were measured using no-motion. With motion, five replicate datasets of 3-minute phase-gated data for each of 3 different periods of motion were acquired. Gated PET images were registered using a multi-resolution level-sets-based non-rigid registration (NRR). The NRR images were then averaged to form a motion-corrected, high-statistics image volume. Spheres from all images were segmented and compared across the imaging conditions. Results: The average center-of-mass range of motion was 7.35, 5.83 and 2.66 mm for the spheres over the three periods of 8, 6 and 4 seconds. The center-of-mass for all spheres in all conditions was corrected to within 1mm on average using NRR as compared to the gated data. For the RRA data, the sphere maximum activity concentration (MAC) was on average 40.2% higher (−4.0% to 116.7%) and sphere volume was on average 12.0% smaller (−8.2% to 28.1%) as compared to the un-gated data with motion. The RRA results for MAC were on average 70% more accurate and for sphere volume 80% more accurate as compared to the un-gated data. Conclusions: The results show that the novel phantom setup and analysis methods are a promising evaluation technique for the assessment of motion correction algorithms. Benefits include the ability to compare against ground truth data without motion but with control of the statistical data quality and background variability. Use of a nonmoving object adjacent to spheres in motion, the spatial extent of the motion correction algorithm was confirmed to be local to the induced motion and to not affect the stationary object. A further benefit of the assessment technique is the use of ground truth data.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"20 1","pages":"2470-2479"},"PeriodicalIF":0.0,"publicationDate":"2012-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79373155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The performance of GridPix detectors","authors":"Y. Bilevych, V. Carballo, M. Fransen, H. van der Graaf, N. de Groot, F. Hartjes, N. Hessey, A. Konig, W. Koppert, M. Rogers, J. Schmitz, R. Schon, J. Timmermans, J. Visschers","doi":"10.1109/NSSMIC.2010.5873901","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5873901","url":null,"abstract":"A GridPix detector is a gaseous detector capable of detecting individual single primary electrons from ionizing particles. Such a detector consists of a pixel chip as active anode covered with a thin layer of silicon rich silicon nitride (SiRN) for protection against discharges, an integrated amplification grid (InGrid), applied on top of the chip by wafer post processing techniques, and a cathode plane. The drift region is between the grid and cathode while the gas gain occurs between the chip and the grid. The discharge quenching properties of the SiRN layer have been determined as well as the relation on grid capacitance, grid voltage and gas mixture. Part of the detectors in this report were of the type Gossip, a GridPix detector with a drift gap of ∼1 mm. Using such thin drift layer, one may consider this detector as a replacement for a silicon pixel detector. The performance of three Gossip detectors has been investigated by measurements in a test beam at CERN.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"58 6 1","pages":"944-948"},"PeriodicalIF":0.0,"publicationDate":"2011-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90682538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of an 8-channel time based readout ASIC for PET applications","authors":"Z. Deng, A. K. Lan, Xishan Sun, C. Bircher, Yinong Liu, Y. Shao","doi":"10.1109/NSSMIC.2010.5874061","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5874061","url":null,"abstract":"An eight-channel readout ASIC has been developed for reading out signals from Silicon Photomultiplier (SiPM) for PET applications. It converts both signal charge and occurring time to digital timing pulses and only needs TDC. It has the advantages of simplified circuit design, reduced power consumption and suitable for large number of readout channels. The ASIC uses a fully current mode preamplifier to obtain high bandwidth (>100MHz) with a few mW/ch power consumption. The dynamic range for charge measurement is adjustable and can be extended up to 103 pC. The chip has been fabricated in 0.35μm 2P4M CMOS technology. A test prototype board for ASIC evaluation has been developed and the preliminary tests show the time jitter is 150ps (rms) by electronics only with injected 30 ns rise time signals, and the coincidence timing is about 1.7 ns (FWHM) for 511 keV photo peak events with LYSO/SiPM detectors. The charge dynamic range is measured to be ∼10bit for electronics only, and better than 1% for detector signals. A simple theoretic analysis shows that the timing and charge resolutions are limited dominately by the detector dark noise in our test and will be studied further. Preliminary evaluations show that the ASIC's functionalities and performance targets have been successfully achieved.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"10 1","pages":"1684-1689"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74267080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FPGA based TDC using Virtex-4 ISERDES blocks","authors":"G. Hegyesi, G. Kalinka, J. Molnár, F. Nagy, J. Imrek, I. Valastyán, Z. Szabó","doi":"10.1109/NSSMIC.2010.5874005","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5874005","url":null,"abstract":"We report on the implementation of an interleaving TDC architecture based on Virtex-4 ISERDES blocks. Multiple ISERDES blocks are used for each input channel in a split-phase arrangement. The architecture has moderate resolution (312 ps in this implementation), it is not sensitive to PVT variations, requires only limited FPGA resources, and thus suitable for high channel counts.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"1 1","pages":"1413-1415"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89388546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy and timing measurement of a PET detector with time-based readout electronics","authors":"Y. Shao, Xishan Sun, K. Lan, C. Bircher, Z. Deng, Yinong Liu","doi":"10.1109/NSSMIC.2010.5874238","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5874238","url":null,"abstract":"New time-based readout (TBR) electronics has been developed and evaluated for its performance and application for PET detectors. It consists of a leading edge (LE) timing threshold for timing pickoff that provides a signal timing t1; a charge integration followed by a constant discharge between two specific timings t2 and t3 that are used to directly measure the signal energy. The timing-walk error caused by LE from signals of different amplitudes can be measured with t1 as a function of different signal amplitudes that is proportional to the time difference between t2 and t3. With this pre-calibration, timing-walk error can be accurately corrected. Therefore, both signal timing and energy can be accurately measured with digital timing signals without using CFD and ADC. These timing signals were controlled and in principle can be measured by an FPGA that can apply many signal logic and data correction algorithms. A single channel discrete component TBR circuit has been implemented in PC board, and 8-channel ASIC chips have been developed for feasibility evaluations and PET detector applications. Initial functionality and performance evaluations have been conducted. Signal amplitude measurement accuracy and linearity are very good; the measured timing accuracy from a pulse is the same as a standard CFD and reaches to ∼100 ps resolution with the test setup. Both suitable energy and coincidence timing resolutions (∼17% and ∼1.0–2.0 ns) were achieved with PMT or Solid-State PM (SSPM) array based PET detectors. Initial studies to acquire flood source crystal identification map has demonstrated the advantages of applying parallel readout with TBR electronics that read out and process signals from each pixel of SSPM array independently. With its relatively simple circuit and low cost, TBR electronics is expected to provide suitable front-end signal readout electronics for compact photon detectors such as SSPM array that require large number of output channels and demand high performance in energy and timing.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"25 1","pages":"2504-2509"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84463309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of equivalence of upslope method-derived myocardial perfusion index and transfer constant based on two-compartment tracer kinetic model","authors":"T. Ichihara, R. George, J. Lima, Y. Ikeda, A. Lardo","doi":"10.1109/NSSMIC.2010.5874200","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5874200","url":null,"abstract":"The purpose of this study was to describe the upslope method-derived myocardial perfusion index using the parameters based on a tracer kinetic model of iodixanol contrast agent and to validate this theoretically derived relationship using an ischemic canine model. The established modified Kety model was used to describe the extravascular diffusion of iodixanol contrast agent, which undergoes no cellular uptake or metabolism. This model consists of two functional compartments, one describing the vascular compartment and the second representing all myocardial capillaries, interstitium, and cells. These compartments are connected by two rate constants, K1 and k2, which represent the first-order transfer constants from the left ventricular (LV) blood to myocardium and from myocardium to the vascular system, respectively. In the early phase after the arrival of contrast agent in the myocardium, the relationship between K1 and the concentrations of iodixanol contrast agent in the myocardium and arterial blood (LV blood) is described by K1 = {dCmyo(tpeak)/dt}/Ca(tpeak) (Eq. 1), where Cmyo(t) is the relative concentration of iodixanol contrast agent in the myocardium at time t, Ca(t) is the relative concentration of iodixanol contrast agent in the LV blood, and tpeak is the time at the peak of Ca(t) and maximum upslope of Cmyo(t). Six canine models of left anterior descending (LAD) artery stenosis were prepared and underwent first-pass contrast-enhanced mult-detector row computed tomography (MDCT) perfusion imaging during adenosine infusion (0.14–0.21 mg/kg/min) to study a wide range of flow rates. K1 was measured using the Patlak plot method and upslope method applied to time-attenuation curve data of the LV blood pool and myocardium. The results were compared against microsphere myocardial blood flow measurements. The Patlak plot-derived K1 and upslope method-derived K1 showed a good linear association. Regional K1 can be measured accurately using the upslope method-derived myocardial perfusion index based on a compartment model.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"14 1","pages":"2330-2333"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78774640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The nanometer beam size monitor (Shintake monitor) at ATF2","authors":"M. Oroku, Y. Yamaguchi, Jaqueline Yan, T. Yamanaka, Y. Kamiya, T. Suehara, S. Komamiya, T. Okugi, N. Terunuma, T. Tauchi, S. Araki, J. Urakawa","doi":"10.1109/NSSMIC.2010.5874041","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5874041","url":null,"abstract":"My presentation focuses on the Shintake (Beamsize) Monitor which can measure nanometer electron beam sizes. The Shintake Monitor is installed in the Accelerator Test Facility 2 (ATF2) at KEK, Japan. ATF2 is a realistic scaled down model of the final focus system for the International Linear Collider. The final focusing scheme named the Local Chromaticity Correction will be tested for the first time in the world. The vertical design beam size at the focal point (virtual interaction point) is 37 nm. Shintake monitor has been designed to measure a beamsize down to 20 nm. It employs the interference pattern made by splitting laser beams and crossing them at the focal point of the electron beam. In their intersecting region, the electromagnetic fields of the two laser beams form a standing wave (interference fringe). The probability of the Compton scattering varies according to the phase of the standing wave where the electrons pass through. Then the total energy of photons from the Compton scattering is measured in a multi-layered ganma ray detector located downstream from the interaction point. This scheme was originally proposed by T. Shintake whose team measured a beamsize of approximately 65 nm with 10 percent resolution at FFTB, SLAC, a former test facility for the ILC. We upgraded this monitor to measure the even smaller beam sizes to be available at ATF2. The laser wavelength has been modified from 1064 nm to 532 nm using a second harmonics generator. The laser optics was newly designed and constructed by implementing a laser wire scheme to measure a larger horizontal beam size, and by enabling different crossing angles of split laser beams to measure a wide (diverse) range of vertical beam sizes. The gamma detector for Shintake monitor has also been newly developed. We evaluated the performance of Shintake monitor with a beam of several microns in size and confirmed its consistency with wire scanner measurements. The expected performance of the Shintake monitor and the current status of the electron beam at ATF, achieved a record in beam size history and near future plan for 37 nm beam size measurement will be mentioned.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"42 1","pages":"1573-1577"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77645738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automation tools in the software development of the TOTEM Detector Control System","authors":"Ivan Atannasov, F. L. Rodríguez, P. Palazzi, F. Ravotti, Sami Stockell, J. Sziklai, V. Tulimaki","doi":"10.1109/NSSMIC.2010.5873774","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5873774","url":null,"abstract":"The TOTEM experiment at the CERN LHC consists of three different subdetectors. Its Detector Control System (DCS) is built with the industry-supplied PVSS system and extended with components developed at CERN through the Joint Controls Project (JCOP). In view of minimizing the development effort and improving reliability, the TOTEM DCS team has developed various technologies to automate the software development process to a large extent. A unified automatic development for all the three subde-tectors of the experiment saves time, produces more reliable software, and makes maintenance less expensive. The automation process described here may be reused in other industrial automation applications.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"124 1","pages":"327-332"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74475195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of the GEANT4 releases 8.2 and 9.2 in terms of a pCT reduced calibration curve","authors":"O. Yevseyeva, Joaquim Teixeira de Assis, E. Milhoretto, I. Evseev, H. Schelin, F. Ahmann, S. Paschuk, J. Setti, V. Denyak, K. S. Diaz, J. M. Hormaza, R. Lopes","doi":"10.1109/NSSMIC.2010.5874220","DOIUrl":"https://doi.org/10.1109/NSSMIC.2010.5874220","url":null,"abstract":"The GEANT4 simulations are essential for the development of medical tomography with proton beams — pCT. In the case of thin absorbers the latest releases of GEANT4 generate very similar final spectra which agree well with the results of other popular Monte Carlo codes like TRIM/SRIM, or MCNPX. For thick absorbers, however, the disagreements became evident. In a part, these disagreements are due to the known contradictions in the NIST PSTAR and SRIM reference data. Therefore, it is interesting to compare the GEANT4 results with each other, with experiment, and with diverse code results in a reduced form, which is free from this kind of doubts. In this work such comparison is done within the Reduced Calibration Curve concept elaborated for the proton beam tomography.","PeriodicalId":13048,"journal":{"name":"IEEE Nuclear Science Symposuim & Medical Imaging Conference","volume":"109 1","pages":"2413-2417"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76875916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}