The U.S. food and drug administration’s role in improving radiation dose management for medical x-ray imaging devices

2021 ◽  
pp. 20210373
Author(s):  
Donald L. Miller ◽  
Smita Kakar ◽  
Lu Jiang ◽  
David C. Spelic ◽  
Laurel Burk

The U.S. Food and Drug Administration (FDA) has been concerned with minimizing the unnecessary radiation exposure of people for half a century. Manufacturers of medical X-ray imaging devices are important partners in this effort. Medical X-ray imaging devices are regulated under both FDA’s electronic product regulations and FDA’s medical device regulations. FDA also publishes guidance documents that represent FDA’s current thinking on a topic and provide a suggested or recommended approach to meet the requirements of a regulation or statute. FDA encourages manufacturers to develop medical devices that conform to voluntary consensus standards. Use of these standards is a central element of FDA’s system to ensure that all medical devices marketed in the U.S. meet safety and effectiveness requirements. FDA staff participate actively in the development and maintenance of these standards, often advancing or introducing new safety and dose management requirements. Use of voluntary consensus standards reduces the amount of time necessary to evaluate a premarket submission and reduces the burden on manufacturers. FDA interacts with industry and other stakeholders through meetings with industry groups, public meetings, public communications, and through the development of voluntary consensus standards. In these interactions, FDA staff introduce new concepts for improving the safety of these devices and provide support for similar initiatives from professional organizations. FDA works with all stakeholders to achieve its mission of protecting and promoting the public health.

RSC Advances ◽  
2015 ◽  
Vol 5 (102) ◽  
pp. 84125-84133 ◽  
Author(s):  
Rémi Samuel ◽  
Edouard Girard ◽  
Grégory Chagnon ◽  
Stéphane Dejean ◽  
Denis Favier ◽  
...  

A family of radiopaque PCL, poly(ε-caprolactone-co-α-triiodobenzoate-ε-caprolactone), has been designed, used and evaluated as macromolecular contrast agent for X-ray imaging of implantable polymeric biomaterials.


1985 ◽  
Vol 19 (1) ◽  
pp. 68-71
Author(s):  
K. Tanaka

Hinotori observed 720 flares through its operation February 1981-October 1981. General discussions of the results were given in two symposia: the Hinotori Symposium (ISAS 1982) and the U.S.-Japan Seminar (de Jager & Švestka 1983). The hard x-ray imaging made at the effective energy 20-35 keV showed a wide variety of morphology. Many flares (22 out of 30 events) showed single source structure, either compact (12) or extended (10) in the spatial resolution of 15 arc sec (Takakura et al. 1983a, Ohki et al. 1983, Takakura 1984). Evidences are given in some limb events that the main source is located in the high corona (1-4 x 104 km) (Takakura et al. 1983b). The extended single source could be the whole coronal loops which may include footpoints, but the maximum brightness is near the loop top. In some events (8 out of 30), weak subsource(s) which sould be identified with the footpoint(s) appear intermittently (Tsuneta et al. 1983). Takakura et al. (1984) found that the extended single source becomes compact and slightly shifts to higher altitudes in later phases of the impulsive burst (5 out of 10 events). Tanaka (1984), Takakura (1984), and Tanaka S Zirin (1984) argued that the hard x-ray morphology of the impulsive burst is consistent with the non-thermal electron beam model in high density corona. Sakurai (1983) investigated magnetic field structures of the hard x-ray sources based on the potential field calculations. Timing between the hard x-ray and microwave in the impulsive bursts was examined by Takakura et al. (1983c), who found correlated subsecond time structures and also by Takakura et al. (1983d), who found a long (5-10 s) delay of the peaks at 17 GHz and E > 300 keV to the peak at E < 100 keV. Kurokawa (1983) showed detailed coincidence between the hard x-ray spikes and Hα brightenings.


Author(s):  
M.G. Baldini ◽  
S. Morinaga ◽  
D. Minasian ◽  
R. Feder ◽  
D. Sayre ◽  
...  

Contact X-ray imaging is presently developing as an important imaging technique in cell biology. Our recent studies on human platelets have demonstrated that the cytoskeleton of these cells contains photondense structures which can preferentially be imaged by soft X-ray imaging. Our present research has dealt with platelet activation, i.e., the complex phenomena which precede platelet appregation and are associated with profound changes in platelet cytoskeleton. Human platelets suspended in plasma were used. Whole cell mounts were fixed and dehydrated, then exposed to a stationary source of soft X-rays as previously described. Developed replicas and respective grids were studied by scanning electron microscopy (SEM).


Author(s):  
James F. Mancuso ◽  
William B. Maxwell ◽  
Russell E. Camp ◽  
Mark H. Ellisman

The imaging requirements for 1000 line CCD camera systems include resolution, sensitivity, and field of view. In electronic camera systems these characteristics are determined primarily by the performance of the electro-optic interface. This component converts the electron image into a light image which is ultimately received by a camera sensor.Light production in the interface occurs when high energy electrons strike a phosphor or scintillator. Resolution is limited by electron scattering and absorption. For a constant resolution, more energy deposition occurs in denser phosphors (Figure 1). In this respect, high density x-ray phosphors such as Gd2O2S are better than ZnS based cathode ray tube phosphors. Scintillating fiber optics can be used instead of a discrete phosphor layer. The resolution of scintillating fiber optics that are used in x-ray imaging exceed 20 1p/mm and can be made very large. An example of a digital TEM image using a scintillating fiber optic plate is shown in Figure 2.


Author(s):  
Ann LeFurgey ◽  
Peter Ingram ◽  
J.J. Blum ◽  
M.C. Carney ◽  
L.A. Hawkey ◽  
...  

Subcellular compartments commonly identified and analyzed by high resolution electron probe x-ray microanalysis (EPXMA) include mitochondria, cytoplasm and endoplasmic or sarcoplasmic reticulum. These organelles and cell regions are of primary importance in regulation of cell ionic homeostasis. Correlative structural-functional studies, based on the static probe method of EPXMA combined with biochemical and electrophysiological techniques, have focused on the role of these organelles, for example, in maintaining cell calcium homeostasis or in control of excitation-contraction coupling. New methods of real time quantitative x-ray imaging permit simultaneous examination of multiple cell compartments, especially those areas for which both membrane transport properties and element content are less well defined, e.g. nuclei including euchromatin and heterochromatin, lysosomes, mucous granules, storage vacuoles, microvilli. Investigations currently in progress have examined the role of Zn-containing polyphosphate vacuoles in the metabolism of Leishmania major, the distribution of Na, K, S and other elements during anoxia in kidney cell nuclel and lysosomes; the content and distribution of S and Ca in mucous granules of cystic fibrosis (CF) nasal epithelia; the uptake of cationic probes by mltochondria in cultured heart ceils; and the junctional sarcoplasmic retlculum (JSR) in frog skeletal muscle.


2000 ◽  
Vol 10 (PR9) ◽  
pp. Pr9-583-Pr9-588 ◽  
Author(s):  
W. A. Gooch ◽  
M. S. Burkins ◽  
G. Hauver ◽  
P. Netherwood ◽  
R. Benck
Keyword(s):  
X Ray ◽  

2020 ◽  
Author(s):  
Keyword(s):  
X Ray ◽  

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