Calibration and evaluation of a transportable in vivo monitoring system for accident monitoring of internal contamination

Youngman, M. J.

doi:10.1093/oxfordjournals.rpd.a006399

Cited by 8 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The following phantom ages were selected for the measurements: 3 months old, 8 and 12 years old and adult [9]. This range of ages not only represents the likely casualties in a radiological incident, but also enabled the optimal measurement geometry on the gamma camera for each age group to be determined.…”

Section: Gamma Camera Physical Calibrationsmentioning

confidence: 99%

Adapting clinical gamma cameras for body monitoring in the event of a large-scale radiological incident

et al. 2016

View full text Add to dashboard Cite

After a release of radionuclides, accidental or otherwise, there will be an urgent need to identify members of the general public who have received a significant intake of radioactive material, sufficient to require medical treatment or further investigation. A large number of people could be contaminated in such an incident. For gamma-ray emitting radionuclides this screening could be carried out using gamma camera medical imaging systems, such as those that are present in many large UK hospital sites. By making a number of simple reversible changes such as removal of collimators, these cameras could be employed as useful additional screening instruments as well as an aid in contamination control. A study was carried out to investigate which systems were present in sufficient number to offer wide scale coverage of UK population centres. Nine gamma cameras (eight dual head and one single head) were assessed using point source and bottle mannequin (BOMAB) phantom measurements so that a mathematical model could be developed for use with the MCNPX Monte Carlo radiation transport code. The gamma camera models were assessed for practical seated and supine geometries to give calibration factors for a list of target radionuclides that could be released in a radiological incident. The minimum detectable activities (MDAs) that were achieved for a five minute measurement demonstrated that these systems are sufficiently sensitive to be used for screening of the general public and are comparable to other body monitoring facilities. While gamma cameras have on-board software that are designed for imaging and provide for a gamma-ray energy range suitable for radionuclides for diagnostic imaging (such as Tc), they are not as versatile as custom-built body monitoring systems.

show abstract

Section: Gamma Camera Physical Calibrationsmentioning

confidence: 99%

Adapting clinical gamma cameras for body monitoring in the event of a large-scale radiological incident

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Besides detecting very high activities for orientation, monitoring portals do not seem to be the right screening equipment to decide meaningfully on the indication of a decorporation treatment. For that purpose whole-body counters seem to be required [ 44 ].…”

Section: Resultsmentioning

confidence: 99%

Preparing for a “dirty bomb” attack: the optimum mix of medical countermeasure resources

et al. 2021

View full text Add to dashboard Cite

Background In radiological emergencies with radionuclide incorporation, decorporation treatment is particularly effective if started early. Treating all people potentially contaminated (“urgent treatment”) may require large antidote stockpiles. An efficacious way to reduce antidote requirements is by using radioactivity screening equipment. We analyzed the suitability of such equipment for triage purposes and determined the most efficient mix of screening units and antidote daily doses. Methods The committed effective doses corresponding to activities within the detection limits of monitoring portals and mobile whole-body counters were used to assess their usefulness as triage tools. To determine the optimal resource mix, we departed from a large-scale scenario (60,000 victims) and based on purchase prices of antidotes and screening equipment in Germany, we calculated efficiencies of different combinations of medical countermeasure resources by data envelopment analysis. Cost-effectiveness was expressed as the costs per life year saved and compared to risk reduction opportunities in other sectors of society as well as the values of a statistical life. Results Monitoring portals are adequate instruments for a sensitive triage after cesium-137 exposure with a high screening throughput. For the detection of americium-241 whole-body counters with a lower daily screening capacity per unit are needed. Assuming that 1% of the potentially contaminated patients actually need decorporation treatment, an efficient resource mix includes 6 monitoring portals and 25 mobile whole-body counters. The optimum mix depends on price discounts and in particular the fraction of victims actually needing treatment. The cost-effectiveness of preparedness for a “dirty bomb” attack is less than for common health care, but costs for a life year saved are less than for many risk-reduction interventions in the environmental sector. Conclusion To achieve economic efficiency a high daily screening capacity is of major importance to substantially decrease the required amount of antidote doses. Among the determinants of the number of equipment units needed, the fraction of the potentially contaminated victims that actually needs treatment is the most difficult to assess. Judging cost-effectiveness of the preparedness for “dirty bomb” attacks is an issue of principle that must be dealt with by political leaders.

show abstract

“…Details of other shielded NaI(Tl) detector based systems with similar characteristics to those described above have been published by Dantas et al (2010), Mizushita (1977) and Summering (1980). The National Radiological Protection Board (now part of PHE) developed and built a transportable whole body monitoring system (Youngman 2001). This system is unusual as two hyper-pure Germanium (HPGe) detectors were used (figure 3).…”

Section: Shielded Systemsmentioning

confidence: 99%

“…The DL for 137 Cs for a 10 min count time is 200 Bq. Detection Limits for other radionuclides with gamma emissions above 100 keV and at least one gamma emission probability of over 10% correspond to effective doses of small fractions of a milli-Sievert (Youngman 2001). Other systems using HPGe detectors have also been described in the literature.…”

Section: Shielded Systemsmentioning

confidence: 99%

Review of methods to measure internal contamination in an emergency

Youngman

2015

J. Radiol. Prot.

View full text Add to dashboard Cite

In the event of a radiation emergency, people close to the site of the incident may be exposed to radiation by external exposure, or as a result of intakes of radioactive material. For these incidents it may be necessary to monitor members of the public both for external and internal contamination. This work reviews currently available equipment for the assessment of internal exposure following an emergency. It concentrates on incidents involving the spread of radioactive material and on contamination by radionuclides which emit penetrating radiation. It is essential that this monitoring is carried out as soon as possible so that people who have been exposed at a level which could have an effect on health can be identified and receive prompt medical assessment. Proposed action levels to identify people who need medical attention are reviewed to determine the required sensitivity of monitoring equipment. For releases containing gamma-ray emitting radionuclides the best means of measuring internal contamination is to use detectors placed close to the body (whole body or partial body monitoring). Laboratory based whole body monitors could be used but these may well be inconveniently located and so equipment which can be deployed to the site of an incident has been developed and these are described. The need for rapid selection and prioritisation of people for monitoring, methods to deal with potentially high numbers of contaminated people and the requirement for a means of rapidly interpreting monitoring information are also discussed.It has been found that for many types of incidents and scenarios, systems based on unshielded high-resolution detectors and hand-held instruments do have the required sensitivity to identify people who require medical assessment.

show abstract

Calibration and evaluation of a transportable in vivo monitoring system for accident monitoring of internal contamination

Cited by 8 publications

References 0 publications

Adapting clinical gamma cameras for body monitoring in the event of a large-scale radiological incident

Adapting clinical gamma cameras for body monitoring in the event of a large-scale radiological incident

Preparing for a “dirty bomb” attack: the optimum mix of medical countermeasure resources

Review of methods to measure internal contamination in an emergency

Contact Info

Product

Resources

About