Applications of justification and optimization in medical imaging: examples of clinical guidance for computed tomography use in emergency medicine.

Availability, reliability, and technical improvements have led to continued expansion of computed tomography (CT) imaging. During a CT scan, there is substantially more exposure to ionizing radiation than with conventional radiography. This has led to questions and critical conclusions about whether the continuous growth of CT scans should be subjected to review and potentially restraints or, at a minimum, closer investigation.

Summary of workshop on CT in emergency medicine: ensuring appropriate use.

This paper addresses the increasing use of CT in medical radiologic imaging, with a focus on applications in emergency medicine. The rapidly increasing use of CT in medical imaging over the past 3 decades has been a major subject in many recent publications, including a discussion of concerns about patient radiation doses, unnecessary CT examinations, and the costs of CT examinations. One area of these concerns has been the use of CT examinations for triage, selection of treatment options, and release of patients from emergency medical settings.

Panel session on "how to meet the challenges for nuclear power".

This panel session at the 2009 Annual Meeting involved a discussion of views of government, industry, and national research laboratory members on the primary future goals in developing advanced nuclear reactor and nuclear fuel cycle designs, fuel management, and used fuel disposal options. The session at the 2009 NCRP Annual Meeting on "How to Meet the Challenges for Nuclear Power" was chaired by Mary E. Clark of the U.

Perspectives of U.S. government agencies on the potential role of greater scientific understanding of low-dose radiation effects in establishing regulatory health protection guidance.

This paper summarizes the perspectives of three U.S. federal agencies on the potential long-term influence of new findings on the biological and potential health effects of low dose and low dose-rate radiation on regulatory controls placed on exposures in occupational, medical, and public settings.

Magnetically induced electric fields and currents in the circulatory system.

Blood flow in an applied magnetic field gives rise to induced voltages in the aorta and other major arteries of the central circulatory system that can be observed as superimposed electrical signals in the electrocardiogram (ECG). The largest magnetically induced voltage occurs during pulsatile blood flow into the aorta, and results in an increased signal at the location of the T-wave in the ECG. Studies involving the measurement of blood pressure, blood flow rate, heart sounds, and cardiac valve displacements have been conducted with monkeys and dogs exposed to static fields up to 1.

Future role of the NCRP in radiation health protection.

The predecessor organizations of the National Council on Radiation Protection and Measurements (NCRP) were established in 1929 (the U.S. Advisory Committee on X-Ray and Radium Protection) and in 1946 (the National Committee on Radiation Protection and Measurements).

Large-scale purification of 90Sr from nuclear waste materials for production of 90Y, a therapeutic medical radioisotope.

A major limitation on the supply of the short-lived medical isotope 90Y (t1/2 = 64 h) is the available quantity of highly purified 90Sr generator material. A radiochemical production campaign was therefore undertaken to purify 1,500 Ci of 90Sr that had been isolated from fission waste materials. A series of alkaline precipitation steps removed all detectable traces of 137Cs, alpha emitters, and uranium and transuranic elements.

The wonders of magnetism.

In this acceptance address for the Bioelectromagnetics Society's 2001 d'Arsonval Award, Dr. Tenforde reviews the highlights of the nonionizing field aspects of his research and scientific service career. These are focused in four areas: (a).