Background: Septal penetration causes collimator-dependent differences in the heart-to-mediastinum (H/M) ratio in I-metaiodobenzylguanidine (MIBG) cardiac imaging. We investigated generally applicable methods to correct such differences.
Methods And Results: Four hours after I-MIBG injection, 40 patients underwent anterior chest imaging successively with medium-energy (ME) and various non-ME collimators. The H/M ratios obtained with the non-ME collimators before and after I-dual-window penetration correction were compared with the ME-derived standard values to determine patient-based conversion equations for empiric and combined corrections, respectively. A I point source was imaged with various collimators, and the central ratio, the ratio of count in a small central region of interest to count in a large one, was calculated. The method of predicting the conversion equations from the central ratios was determined. Correction using the patient-based conversion equations removed systematic underestimation of the H/M ratios obtained with the non-ME collimators, and combined correction depressed residual random errors to some degree. Point-source-based equations yielded results comparable to the patient-based equations.
Conclusions: Empiric and combined corrections effectively reduce collimator-dependent differences in the H/M ratio. The conversion equations can be predicted from simple point-source imaging, which would allow to apply these corrections to data obtained with various collimators.
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http://dx.doi.org/10.1007/s12350-016-0546-8 | DOI Listing |
J Environ Manage
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School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China. Electronic address:
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United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
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Smart Forming Process Group, Korea Institute of Industrial Technology, Ulsan 44776, Republic of Korea.
For allowable defect analyses, the fracture toughness of materials needs to be accurately predicted. In this regard, a lower fluctuation of fracture toughness can lead to reduction in safety and economic risks. Crack tip opening displacement (CTOD), which is the representative parameter for fracture toughness, can be measured by various methods, such as the δ5, the J-conversion method, the single clip gauge method, and the double clip gauge method.
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Laboratory for Heteroepitaxial Growth of Functional Materials & Devices, Department of Chemical & Biological Engineering, State University of New York (SUNY) at Buffalo, Buffalo, NY 14260, USA.
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View Article and Find Full Text PDFMembranes (Basel)
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Department of Biophysics, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, 19 H. Jordan Str., 41-808 Zabrze, Poland.
One of the most important formalisms used to describe membrane transport is Onsager-Peusner thermodynamics (TOP). Within the TOP framework, a procedure has been developed for the transformation of the Kedem-Katchalsky (K-K) equations for the transport of binary electrolytic solutions across a membrane into the Kedem-Katchalsky-Peusner (K-K-P) equations. The membrane system with an Ultra Flo 145 Dialyser membrane used for hemodialysis and aqueous NaCl solutions was used as experimental setup.
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