2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)最新文献

{"title":"The dynamic digital radiography system design and data calibration method for monitoring the running aero-engine","authors":"Ming Chang, Yongshun Xiao, Zhiqiang Chen","doi":"10.1109/NSSMIC.2014.7431132","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7431132","url":null,"abstract":"To improve the aerodynamic performance and efficiency, monitoring the exact geometry and position information of the internal structure with the aero-engine under various operational statuses is a very important and meaningful job task. First, a dynamic digital radiography system is designed for the data acquisition in this paper. However the exposure time of each frame is limited by the rapid rotating speed of the aero-engine, which eventually leads to a high noise level and the loss of low-contrast structures in the acquired image. Therefore the average of multi-frame images, with the aero-engine under a stable operation state, is needed and a synchronization device is used to control the accelerator x-ray source in the system. Second, the body vibration of the running aero-engine often results in the blurs of the averaging image. The marker based data calibration and correction method is presented. Three steel balls are used as the markers to estimate the vibration parameters and data calibrations. The dynamic digital radiography model is built with such parameters to recover a clear image from the images of multi-frames. Finally, experiments are carried out to demonstrate the effectiveness and feasibility of the proposed system design and corresponding data calibration methods.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127769308","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":"Validation of convolution based forced detection SIMIND with analytical collimator response modeling using GATE","authors":"M. I. Karamat, T. Farncombe","doi":"10.1109/NSSMIC.2014.7430827","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7430827","url":null,"abstract":"Monte Carlo is an important and well established research tool in emission tomography. While used extensively in research applications, Monte Carlo techniques are not typically implemented clinically due to is its low detection efficiency and resultant long acquisition times. In order to make this notoriously slow computational tool faster, variance reduction techniques known as convolution based forced detection (CFD) have previously been implemented into SIMIND MC code (CFD-SIMIND) by our group. In this method, at each interaction site within the object, photons are forced to travel in a direction perpendicular to the detector and are convolved with a Gaussian blurring kernel based on the collimator response. This study focuses on the feasibility of using CFD-SIMIND in the absence of septal penetration and collimator scatter modeling for low and medium energy isotopes. In this study, the results of CFD-SIMIND have been compared with GATE Monte Carlo in order to validate the CFD-SIMIND results. For this purpose a number of point source simulations were performed using CFD-SIMIND and GATE with low and medium energy isotopes (i.e. 99mTc and 111In respectively). 99mTc point source data (with low and medium energy collimator) and 111In (with medium energy collimator) at different source to collimator distances in air and water was acquired. The point source data was then used for the validation of CFD-SIMIND in terms of spatial resolution, sensitivity, image profiles and energy spectra. In order to validate the results for extended source distribution and non-uniform attenuation media, XCAT phantom simulations are being performed. The 99mTc data with low energy collimator, available so far, has also been presented in the study. A comparison similar to point source data obtained in water was also performed in this case. It has been observed that CFD-SIMIND correlates well with GATE for simple point source simulation data in the case of 99mTc and 111In even in the absence of collimator scatter and septal penetration modeling. Point source as well as XCAT phantom data for 99mTc with low energy collimator showed that the use of CFD-SIMIND is valid for the isotope/collimator combination. In order to generalize the results, further simulation studies for other isotope/collimator pairs, used in point source simulations, are being performed for XCAT phantom.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126378905","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":"Mobile outdoor SuperMISTI Compton imager","authors":"E. Wulf, A. Hutcheson, L. Mitchell, R. Woolf, B. Phlips","doi":"10.1109/NSSMIC.2014.7431108","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7431108","url":null,"abstract":"The SuperMISTI coded aperture imager trailer has been modified as a Compton imager with a 5 × 5 array of either NaI or plastic detectors and a 6 × 13 array of NaI detectors separated by 1.66 m. Gamma-ray sources were located by both the NaI-NaI and the Plastic-NaI imagers at 10s of meters standoff distances. The results from the new Compton cameras are compared to the coded aperture imager that also utilizes the 6 × 13 array of NaI detectors.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125674606","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 X'tal cube PET detector of isotropic (0.8 mm)3 crystal segments","authors":"M. Nitta, N. Inadama, Y. Hirano, F. Nishikido, E. Yoshida, H. Tashima, H. Kawai, T. Yamaya","doi":"10.1109/NSSMIC.2014.7430754","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7430754","url":null,"abstract":"Depth-of-interaction measurement is essential for PET to reduce the parallax error, resulting in improved spatial resolution with maintaining sensitivity. One of ultimate goals of improvement in DOI detectors is achieving isotopic spatial resolution. For this purpose, we have developed an isotropic 3D position sensitive PET detector named X'tal cube. The X'tal cube is composed of a scintillation crystal block segmented into cubes. Arrays of multi pixel photon detectors (MPPCs) cover all surfaces of the crystal block. In our previous study, we achieved 1.0 mm isotropic spatial resolution. In this study, we finally succeeded to develop the X'tal cube with (0.8 mm)3 isotropic segments. The scintillation crystal block was a 13.6 × 13.6 × 13.6 mm3 monolithic LYSO. 3D segmentation of 17 × 17 × 17 array of 0.8 mm × 0.8 mm × 0.8 mm grids was made by the laser processing. We used 96 MPPCs (S12642-0404PB-50(X)). For each face of the crystal block, monolithic 4 × 4 array of MPPCs with about 0.2 mm gaps was coupled. The position histograms were made by the 3D Anger-type calculation from uniform irradiation data, which showed good identification of each segments. We obtained 9.0% energy resolution for the central part of the crystal block. In conclusion, we succeeded to develop a prototype PET detector with the world's finest segments of (0.8 mm)3 grids.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125782177","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":"Radiation damage of the multi-pixel photon counter to be used for in-beam PET in carbon therapy","authors":"F. Nishikido, Y. Hirano, A. Mohammadi, T. Yamaya","doi":"10.1109/NSSMIC.2014.7430978","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7430978","url":null,"abstract":"We are developing the OpenPET for in-beam imaging in carbon ion therapy. We have succeeded in showing a proof-of-concept by developing small OpenPET prototypes that we used in the HIMAC. One of the major issues to realize the OpenPET is radiation damage to detectors because a number of fragmented particles are incident on the detectors located downstream from the target. While we are currently using photo-multiplier tubes in the OpenPET, some groups reported feasibility of use of a semiconductor photo-detector in hadron therapy. In this paper, therefore, we tested radiation hardness of the multi-pixel photon counter (MPPC) to show feasibility of its use in the OpenPET for carbon ion therapy. We used a single pixel MPPC (S10931-050) to evaluate radiation hardness. The experiment was performed in the PH2 course of the HIMAC. The energy of the 12C beam was 290MeV/u and beam intensity was 1.6 × 109 particles per second (pps) which was ten times higher than the typical clinical beam intensity. The carbon ions entered and stopped in a water phantom (10 × 10 × 20 mm3). The MPPC was 30 cm from the back end of the water phantom at an angle of 30 degrees. We measured the energy spectrum for 22Na point source and the dark count spectrum before and after 10, 20, 30, 40, 50, 70 min irradiations. We found pulse height and energy resolution of the energy spectra were degraded as the irradiation time was increased.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127929204","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":"CCD-based diagnostics for pulsed MeV photon beams","authors":"Yigong Zhang, B. Quiter, P. Barton, B. Plimley, K. Vetter, C. Geddes","doi":"10.1109/NSSMIC.2014.7431240","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7431240","url":null,"abstract":"Narrow bandwidth, MeV-level photon beams can be generated by Thomson scattering of laser light from fast electrons. Intense photon sources (> 1 MeV, 108 photons/shot) from laser plasma accelerated GeV electrons present the possibility for compact active interrogation devices. However, the characterization of such intense photon beams is inherently challenging due to mm-scale focusing and fs-scale pulse duration. A solution to the characterization of both spatial and energy distributions of each shot is to employ a low mass scattering material and track the scattered Compton electron's direction and energy. Following previous work at UC Berkeley with electron track Compton imaging in fully-depleted silicon CCDs, we present a measurement scheme for the shot-by-shot measurement of MeV photon beam position and energy.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121758155","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":"A dedicated analog digital converter for silicon photomultiplier readout","authors":"W. Shen, K. Briggl, Huangshan Chen, H. Schultz-Coulon","doi":"10.1109/NSSMIC.2014.7431044","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7431044","url":null,"abstract":"The analog digital converter (ADC) designed in UMC 0.18 μm CMOS technology is dedicated to the SiPM analog readout frontend “KLauS” developed before for the international linear collider (ILC) scintillator-based analog hadron calorimeter (AHCal). In order to make the carlorimeter as compact as possible, an extremly low power consumption is required by the AHCal such that active cooling can be avoided in the system. The upper limit of the power consumption is set to only 25 μW per channel with a 1% occupancy in the power pulsing mode. An 10-bit successive approximation register (SAR) structure is chosen for this application. The SAR structure with a capacitive digital-analog-converter (DAC) array promises a rather low power consumption. Moreover, a 10-bit resolution can be achieved without any digital calibration method and is sufficient for the minimum ionizing particle (MIP) response in the AHCal as well. For the special calibration mode of the AHCal operation, where SiPM single photon spectra are required for the pixel gain calculation, another pipelined stage can be attached to the SAR ADC such that a 12-bit resolution can be achieved. In addition to these, a peak-sensing track and hold unit is also implemented in front of the SAR ADC, the error for the self-held voltage is simulated to be less than 0.5 LSB in the 10-bit SAR ADC for an input voltage amplitude from 10 mV to 1 V. By using the peak-sensing method, the sampling frequency of the ADC is also reduced down to 2 MHz, which is still larger than the expected maximum event rate in the AHCal. The simulated DNL is less than 0.5 LSB in the worst case for the 10-bit SAR module and less than 0.3 LSB after calibration for the pipelined 12-bit module. The total power consumption of the nominal MIP operation mode is less than 600μW for an event rate of 2 MHz without any power pulsing techniques. The design details and the simulation results are presented.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131374350","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":"A digital system for artificial generation of images from radiation detectors","authors":"F. Caponio, A. Abba, N. Lusardi, A. Geraci","doi":"10.1109/NSSMIC.2014.7431136","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7431136","url":null,"abstract":"We present the progress performed in the development of a digital fully programmable emulator of radiation detectors and front-end electronics of image acquisition systems. The instrument has 64 independent channels with the capability of growing an image that has been a-priori programmed. The growth faithfully emulates the real-time behavior of an acquisition array constituted by 64 detectors, also based on photomultipliers, that are exposed to a source spatially distributed. The emulation process achieves the performance of 3□106 counts per second, i.e. emulated samples of generated charge. The instrument has also the features of adding spatial and temporal pile-up and noise with fully programmable characteristics. The presence of DACs clocked at 140 MSPS makes available the output stream also in analog format.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131925789","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":"CT density driven continuous bed motion acquisition","authors":"V. Panin, H. Bal, M. Casey","doi":"10.1109/NSSMIC.2014.7431030","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7431030","url":null,"abstract":"Constant velocity continuous bed motion (CBM) and constant time per bed step and shoot acquisitions result in axially non-uniform noise distribution over the whole body image. The effect is largely due to the axially variable patient attenuation. With the addition of variable bed speed capabilities, CBM becomes an acquisition generalization tool for axial sensitivity modeling; therefore a flexible tool in local image quality adjustment. The variance introduced through the CBM sensitivity profile can diminish noise nonuniformity that occurs due to patient attenuation.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132521948","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":"Improving lesion detectability in low uptake 18 F-FDG breast cancer by optimizing PET imaging time","authors":"K. Wangerin, M. Muzi, L. Peterson, Finbarr O 'sullivan, H. Linden, D. Mankoff, Paul Kinahan","doi":"10.1109/NSSMIC.2014.7430811","DOIUrl":"https://doi.org/10.1109/NSSMIC.2014.7430811","url":null,"abstract":"There have been anecdotal reports that delayed FDG-PET oncology imaging can improve the SNR for known lesions. Our goal was to evaluate if it is possible to optimize lesion detectability by adjusting the duration between FDG injection and image acquisition. Methods: We combined three components: a kinetic model of 18FFDG radiotracer uptake, a forward model of PET data acquisition, and observer models to estimate lesion detectability. Model parameters and arterial input functions were estimated from dynamic PET studies of patients with early-stage breast cancer. These were used to generate time-activity curves (TACs). For each TAC, realistic PET sinograms were simulated, and images were reconstructed using OSEM. There were 600 i.i.d. realizations for each case. Both nonprewhitening matched filter (NPWMF) and channelized Hoteling observer (CHO) statistics were used to generate receiver operating characteristic (ROC) curves, which were summarized using the area under the curve (AUC). Results: The AUC increased for several hours past the current standard post-injection imaging window of one hour. This improvement is driven by the continued accumulation of FDG in the tumor before the impact of increased noise due to radiotracer decay begins to dominate. Conclusion: These results imply that delayed PET imaging may reveal low-conspicuity lesions in patients that would have otherwise gone undetected. However, further validation of this approach is needed.","PeriodicalId":144711,"journal":{"name":"2014 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131507009","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}