The Experts below are selected from a list of 3848022 Experts worldwide ranked by ideXlab platform
Albert Macovski - One of the best experts on this subject based on the ideXlab platform.
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rapid fully automatic arbitrary volume In Vivo shimmIng
Magnetic Resonance in Medicine, 1991Co-Authors: Peter Webb, Albert MacovskiAbstract:MR spectroscopy and many MR imagIng methods benefit from a well-shimmed magnet. We have developed a pulse sequence which enables fast and accurate measurement of three-dimensional field maps In Vivo, and a data analysis package that allows calculation of shim currents to optimally shim arbitrary selected volumes. A data lInk to the shim power supply allows automatic update of currents. No Intervention by the operator is required. Typical In Vivo shimmIng time is less than 5 mIn. Performance analysis, phantom, and In Vivo results are presented. © 1991 Academic Press, Inc.
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Rapid, fully automatic, arbitrary‐volume In Vivo shimmIng
Magnetic Resonance in Medicine, 1991Co-Authors: Peter Webb, Albert MacovskiAbstract:MR spectroscopy and many MR imagIng methods benefit from a well-shimmed magnet. We have developed a pulse sequence which enables fast and accurate measurement of three-dimensional field maps In Vivo, and a data analysis package that allows calculation of shim currents to optimally shim arbitrary selected volumes. A data lInk to the shim power supply allows automatic update of currents. No Intervention by the operator is required. Typical In Vivo shimmIng time is less than 5 mIn. Performance analysis, phantom, and In Vivo results are presented. © 1991 Academic Press, Inc.
Peter Webb - One of the best experts on this subject based on the ideXlab platform.
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rapid fully automatic arbitrary volume In Vivo shimmIng
Magnetic Resonance in Medicine, 1991Co-Authors: Peter Webb, Albert MacovskiAbstract:MR spectroscopy and many MR imagIng methods benefit from a well-shimmed magnet. We have developed a pulse sequence which enables fast and accurate measurement of three-dimensional field maps In Vivo, and a data analysis package that allows calculation of shim currents to optimally shim arbitrary selected volumes. A data lInk to the shim power supply allows automatic update of currents. No Intervention by the operator is required. Typical In Vivo shimmIng time is less than 5 mIn. Performance analysis, phantom, and In Vivo results are presented. © 1991 Academic Press, Inc.
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Rapid, fully automatic, arbitrary‐volume In Vivo shimmIng
Magnetic Resonance in Medicine, 1991Co-Authors: Peter Webb, Albert MacovskiAbstract:MR spectroscopy and many MR imagIng methods benefit from a well-shimmed magnet. We have developed a pulse sequence which enables fast and accurate measurement of three-dimensional field maps In Vivo, and a data analysis package that allows calculation of shim currents to optimally shim arbitrary selected volumes. A data lInk to the shim power supply allows automatic update of currents. No Intervention by the operator is required. Typical In Vivo shimmIng time is less than 5 mIn. Performance analysis, phantom, and In Vivo results are presented. © 1991 Academic Press, Inc.
A Heerschap - One of the best experts on this subject based on the ideXlab platform.
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Current status of human In Vivo NMR spectroscopy.
European journal of radiology, 1992Co-Authors: A HeerschapAbstract:Various aspects of the In Vivo NMR spectroscopic approach to elucidate metabolic processes In humans are summarized. This Includes the In Vivo quantities that can be observed by this method, technical and methodological development (such as localization, spectral editIng and quantitation) and the scope of current human In Vivo NMR spectroscopy.
B.j. Mijnheer - One of the best experts on this subject based on the ideXlab platform.
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automatic In Vivo portal dosimetry of all treatments
Physics in Medicine and Biology, 2013Co-Authors: I Olacireguiruiz, B.j. Mijnheer, R Rozendaal, M Van Herk, A MansAbstract:At our Institution EPID (electronic portal imagIng device) dosimetry is routInely applied to perform In Vivo dose verification of all patient treatments with curative Intent sInce January 2008. The major impediment of the method has been the amount of work required to produce and Inspect the In Vivo dosimetry reports (a time-consumIng and labor-Intensive process). In this paper we present an overview of the actions performed to implement an automated In Vivo dosimetry solution clInically. We reimplemented the EPID dosimetry software and modified the acquisition software. Furthermore, we Introduced new tools to periodically Inspect the record-and-verify database and automatically run the EPID dosimetry software when needed. In 2012, 95% of our 3839 treatments scheduled for In Vivo dosimetry were analyzed automatically (27,633 portal images of Intensity-modulated radiotherapy (IMRT) fields, 5551 portal image data of VMAT arcs, and 2003 portal images of non-IMRT fields). The In Vivo dosimetry verification results are available a few mInutes after delivery and alerts are immediately raised when deviations outside tolerance levels are detected. After the clInical Introduction of this automated solution, Inspection of the detected deviations is the only remaInIng work. These newly developed tools are a major step forward towards full Integration of In Vivo EPID dosimetry In radiation oncology practice.
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The role of In Vivo dosimetry
Radiotherapy and Oncology, 1993Co-Authors: G. Garavaglia, Karl-axel Johansson, G. Leunens, B.j. MijnheerAbstract:In recent years, numerous publications have shown the feasibility and usefulness of In Vivo dosimetry as an essential tool of quality assurance programs In radiotherapy [ 1,3,6,11]. In the context of this meetIng on high dose/high precision radiotherapy, the presentations and discussions on In Vivo dosimetry centred on its value for InvestigatIng the quality of specific treatment techniques: accuracy and reproducibility In dose delivery, benchmark role of In Vivo dosimetyy, frequency of In Vivo measurements and action levels for corrective actions.
H J Ahr - One of the best experts on this subject based on the ideXlab platform.
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CiprofloxacIn: In Vivo genotoxicity studies.
Mutation research, 2001Co-Authors: B A Herbold, S Y Brendler-schwaab, H J AhrAbstract:The fluoroquInolone ciprofloxacIn is widely used In antimicrobial therapy. It Inhibits the bacterial gyrase and In high concentrations In vitro also the functionally related eukaryotic topoisomerase-II, which resulted In genotoxic effects In several In vitro tests. In order to evaluate the relevance of these fIndIngs, ciprofloxacIn was tested In Vivo for genotoxic activity usIng the followIng test systems: micronucleus test In bone marrow of mice, cytogenetic chromosome analysis In ChInese hamster, domInant lethal assay In male mice and UDS tests In primary rat and mouse hepatocytes In Vivo. These results are compared with already published In vitro and In Vivo studies with ciprofloxacIn. All In Vivo genotoxicity revealed no genotoxic effect for ciprofloxacIn. In addition, ciprofloxacIn was found to be non-carcInogenic In two rodent long-term bioassays. Therefore, ciprofloxacIn is considered to be safe for therapeutic use.
