1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference最新文献_第8页

Distortion compensation of electronic endoscope image 电子内窥镜图像的畸变补偿

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.373585

H. Haneishi, Y. Miyake

引用次数: 9

Characterization of sampling schemes for whole body PET imaging 全身PET成像取样方案的特性

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.373614

M. Dahlbom, P. Cutler, W. Digby, W. K. Luk, J. Reed

{"title":"Characterization of sampling schemes for whole body PET imaging","authors":"M. Dahlbom, P. Cutler, W. Digby, W. K. Luk, J. Reed","doi":"10.1109/NSSMIC.1993.373614","DOIUrl":"https://doi.org/10.1109/NSSMIC.1993.373614","url":null,"abstract":"Whole body PET images suffers by relatively high noise levels due to inherent poor counting statistics in the emission data. It is therefore important to optimize the acquisition parameters to minimize any additional noise contamination. It has previously been shown that using a continuous or redundant acquisition scheme, improvements in noise characteristics and image quality are seen. In this work the continuous sampling is further characterized and compared to the conventional step and shoot acquisition. The main sources of noise contamination using conventional sampling is due to the normalization procedure which is applied to the emission data. By using continuous sampling and using a common normalization for all planes, the statistical noise in the normalization is improved by factor close to the number of planes in the scanner. The continuous sampling showed to be less sensitive to small patient movements (<5 mm) compared to conventional scanning. Previously reported problems of data handling have been resolved by rewriting the acquisition firmware to allow on-line addition of the redundant sampled data in hardware.<<ETX>>","PeriodicalId":287813,"journal":{"name":"1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference","volume":"35 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132717292","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}

引用次数: 26

Qualification Of Modern Electrical Products To Original Plant Specifications 现代电器产品按原厂规范进行鉴定

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.701800

C. Thibault, G. L. Hanna

引用次数: 0

New complete-data spaces and faster algorithms for penalized-likelihood emission tomography 新的完整数据空间和更快的惩罚似然发射断层扫描算法

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.373624

J. Fessler, A. Hero

{"title":"New complete-data spaces and faster algorithms for penalized-likelihood emission tomography","authors":"J. Fessler, A. Hero","doi":"10.1109/NSSMIC.1993.373624","DOIUrl":"https://doi.org/10.1109/NSSMIC.1993.373624","url":null,"abstract":"The classical expectation-maximization (EM) algorithm for image reconstruction suffers from particularly slow convergence when additive background effects such as accidental coincidences and scatter are included. In addition, when smoothness penalties are included in the objective function, the M-step of the EM algorithm becomes intractable due to parameter coupling. The authors describe the space-alternating generalized EM (SAGE) algorithm, in which the parameters are updated sequentially using a sequence of small \"hidden\" data spaces rather than one large complete-data space. The sequential update decouples the M-step, so the maximization can typically be performed analytically. By choosing hidden-data spaces with considerably less Fisher information than the conventional complete-data space for Poisson data, the authors obtain significant improvements in convergence rate. This acceleration is due to statistical considerations, not to numerical overrelaxation methods, so monotonic increases in the objective function and global convergence are guaranteed. Due to the space constraints, the authors focus on the unpenalized case in this summary, and they eliminate derivations that are similar to those in Lange and Carson, J. Comput. Assist. Tomography, vol. 8, no. 2, p.306-16 (1984).<<ETX>>","PeriodicalId":287813,"journal":{"name":"1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133010647","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}

引用次数: 16

Simulation and measurement of spatial resolution in detection of annihilation radiation with BGO crystals 用BGO晶体探测湮灭辐射的空间分辨率模拟与测量

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.373590

D. McDaniel, B. D. Johnston, D.C. Wack, J.J. Williams

{"title":"Simulation and measurement of spatial resolution in detection of annihilation radiation with BGO crystals","authors":"D. McDaniel, B. D. Johnston, D.C. Wack, J.J. Williams","doi":"10.1109/NSSMIC.1993.373590","DOIUrl":"https://doi.org/10.1109/NSSMIC.1993.373590","url":null,"abstract":"Spatial resolution performance measurements of PET scanners are sensitive to the long tails of the angular distribution of the annihilation radiation, to a degree not previously appreciated. The non-Gaussian nature of the positron range, angular distribution of annihilation radiation, and scatter-induced spatial distribution of scintillator energy deposition prevents simple (e.g. quadrature-based arguments) methods of performance estimation, and requires full numerical convolution of the 3D spatial profiles. The authors have developed a Monte Carlo simulation of 511 keV gamma ray interactions with scintillator crystals to model the spatial distributions obtained in projection measurements of annihilation radiation from point sources. The authors find good agreement between the simulations and experimental results obtained with BGO-based crystals, both for optically-isolated crystals embedded in a crystal matrix, and for a conventional, Anger-based BGO block detector. There is approximately a 0.3 mm difference in the coincidence response function FWHM between 4 mm isolated and Anger crystals which is reproduced by the Monte Carlo calculations.<<ETX>>","PeriodicalId":287813,"journal":{"name":"1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference","volume":"24 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113959732","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}

引用次数: 2

Non-linear Response In The Scintillation Yield Of Lu/sub 2/ SiO/sub 5/ O:Ce/sup 3+/ Lu/sub 2/ SiO/sub 5/ O:Ce/sup 3+/闪烁产率的非线性响应

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.701745

P. Dorenbos, J. D. de Haas, C. V. van Eijk, C. Melcher, J. Schweitzer

引用次数: 66

Assessment of scatter components in multispectral PET imaging 多光谱PET成像中散射分量的评估

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.373541

M. Bentourkia, P. Msaki, J. Cadorette, R. Lecomte

引用次数: 6

An adaptive Gaussian filter for noise reduction and edge detection 用于降噪和边缘检测的自适应高斯滤波器

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.373563

Guang Deng, L. Cahill

引用次数: 333

Constrained IntraSPECT reconstruction from SPECT projections 从SPECT投影中约束IntraSPECT重建

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.373561

S. Manglos, T. M. Young

引用次数: 33

A multiloop coupled resonator coil design for MRI MRI多回路耦合谐振线圈设计

1993 IEEE Conference Record Nuclear Science Symposium and Medical Imaging Conference Pub Date : 1993-10-31 DOI: 10.1109/NSSMIC.1993.373565

K. Derby

引用次数: 0