Reference Table NRSI 2007
Search parameters: 0-18 y/o children; ionizing radiation; imaging; past 10 y
Reference (use MEDLINE citation)
Study
Design
Type*
Shannoun F, Zeeb H, Back C, Blettner M
Number
of
Patients
Potential impact of the American College of
Radiology appropriateness criteria on CT for
trauma.
AJR Am J Roentgenol. 2006 Apr;186(4):937-42.
PMID: 16554560
Biju K, Nagarajan PS.
Normalized organ doses and effective doses to a
reference Indian adult male in conventional
medical diagnostic x-ray examinations.
Health Phys. 2006 Mar;90(3):217-22.
PMID: 16505618
Lu ZF, Nickoloff EL, Ruzal-Shapiro CB, So JC,
Dutta AK.
New automated fluoroscopic systems for pediatric
applications.
J Appl Clin Med Phys. 2005 Fall;6(4):88-105.
*Study Design types:
1=Systematic review or meta-analysis of randomized controlled trial
2=Randomized controlled trial
3=Nonrandomized controlled trial
4=Observational (a=cohort, b=cross-sectional, c=case-control study)
Study Objective(s)
>425,000
National (Luxembourg)
evaluation on radiation doses
from diagnostic procedures (xr
and nm)
200
To identify current imaging
utilization patterns at a level 1
trauma center, the radiation dose
and financial costs of this
imaging, and what impact, if any,
the ACR appropriateness criteria
might have on these factors
Medical exposure of the population from
diagnostic use of ionizing radiation in
luxembourg between 1994 and 2002.
Health Phys. 2006 Aug;91(2):154-62.
PMID: 16832196
Hadley JL, Agola J, Wong P.
Kaste SC
Dose computations of 80 kV
diagnostic x-rays made on
mathematical phantom
representing average Indian adult,
since it is felt that results based on
MIRD adult phantom calculations
are not strictly appropriate for the
population in India.
To investigate strategies for
pediatric fluoroscopy in order to
minimize the radiation exposure
to these individuals, while
maintaining effective diagnostic
image quality
5=Non-experimental study
6=Expert opinion
7=General review article
Study Findings
Increase of annual effective dose per capita from 1.59 mSv in
1994 to 1.98 mSv in 2002. Impact of CT to dose received
from medical use of radiation dramatically increased in this
time period. Luxembourg has one of the highest CT
examination rates compared to other health care level I
countries. Proposed measures to minimize medical exposures:
medical physicists should have a more central role in patient
dosimetry in IR and diagnostic radiology, especially CT.
Implementation of electronic "X-ray patient card" for all
irradiated patients--except dental--and use of European
referral criteria that give guidance and recommend
investigations in various clinical settings can both help to
decrease medical radiation exposures.
Total of 660 CT examinations performed for a total charge of
$837,028. Estimated effective dose of 16 mSv sustained by
typical patient in the study. Application of ACR criteria found
to have potential reduction imaging costs by 39% and
estimated radiation dose by 44%. Thus, ACR appropriateness
criteria have potential for strong positive impact on overall
cost of imaging and radiation dose received for patients in
trauma setting.
As external phantom dimensions are nearly the same as 15-yold NRPB pediatric phantom, our results are compared with
those of latter and agreement found to be satisfactory
For pediatric patients, the automated system can employ
additional filtration, special automatic brightness control
curves, pulsed fluoroscopy, and other features to reduce the
patient radiation exposures without significantly
compromising the image quality. Benefits gained from
optimal selection of automated programs and settings for
Reference Table NRSI 2007
Search parameters: 0-18 y/o children; ionizing radiation; imaging; past 10 y
Epub 2005 Nov 21.
PMID: 16421503
Orchard JW, Read JW, Anderson IJ.
7
na
Review
7
Review
Describes system of regulation
and practical guidance that has
been developed in the UK for
implementing the requirement in
the EC Medical Exposure
Directive that all Member States
shall promote the establishment
and use of diagnostic reference
levels (DRLs) for medical X-ray
examinations
The use of diagnostic imaging in sports medicine.
Med J Aust. 2005 Nov 7;183(9):482-6. Review.
PMID: 16274353
Mansson LG, Bath M, Mattsson S.
Priorities in optimisation of medical X-ray
imaging--a contribution to the debate.
Radiat Prot Dosimetry. 2005;114(1-3):298-302.
PMID: 15933125
Wall BF
Implementation of DRLs in the UK.
Radiat Prot Dosimetry. 2005;114(1-3):183-7.
PMID: 15933105
Regulla DF, Eder H.
fluoroscopy include ease of operation, better image quality,
and lower patient radiation exposures
Plain x-ray should still generally be the first imaging
technique; exceptions include some forms of superficial
tendinopathy, in which ultrasound may be more appropriate,
and situations where radiation exposure is contraindicated,
such as in a pregnant patient. The cost of the examination to
the patient and the community should also be considered (eg,
ultrasound v magnetic resonance imaging).
For CT, true optimisation of trade-off between radiation dose
and image quality is more likely to be effective. Both number
of CT examinations per year and effective dose per
examination are increasing from technical advances in CT-jointly leading to steady increase in collective dose from CT.
The smaller influence of anatomical background in CT gives
high correlation between detection tasks and radiation dose.
Thus, a reasonable view on which examinations to optimise is
to give priority to CT examinations. The recommended
distribution of a full working week for optimisation, based on
relative lifetime risk of lethal cancer from diagnostic X rays
and total collective dose from CT, is to use three out of five
days to optimise CT examinations, of which one day should
be devoted to paediatric CT.
Indications in patient dose reduction for some CT
examinations are reported. Progress in formally adopting
numerical values for 'national DRLs', as required by the UK
regulations, and the provision of authoritative guidance on
implementation of DRLs at local level, also discussed.
Exposure data acquired and assessed in Germany for 1997
resulted in mean annual effective dose of 2 +/- 0.5 mSv per
head of the population, thus reaching or exceeding average
level of environmental radiation in many cases. Underlying
frequency of medical X-ray exams was ~136 million, i.e.
approximately 1.7 exams annually per head of population.
Patient exposure in medical X-ray imaging in
Europe.
Radiat Prot Dosimetry. 2005;114(1-3):11-25.
PMID: 15933076
*Study Design types:
1=Systematic review or meta-analysis of randomized controlled trial
2=Randomized controlled trial
3=Nonrandomized controlled trial
4=Observational (a=cohort, b=cross-sectional, c=case-control study)
Kaste SC
5=Non-experimental study
6=Expert opinion
7=General review article
Reference Table NRSI 2007
Search parameters: 0-18 y/o children; ionizing radiation; imaging; past 10 y
Seibert JA.
7
Review
Tradeoffs to be considered
between image quality and
radiation dose, which is the main
topic of this article
phantoms
An experimental study for
optimizing the automatic
exposure control (AEC) for
cardiac angiography.
phantoms
To present a series of tissueequivalent (TE) materials
designed to radiographically
mimic human tissue at diagnostic
photon energies. These tissue
Tradeoffs between image quality and dose.
Pediatr Radiol. 2004 Oct;34 Suppl 3:S183-95;
discussion S234-41. Review.
PMID: 15558260
Onnasch DG, Schemm A, Kramer HH.
Optimization of radiographic parameters for
paediatric cardiac angiography.
Br J Radiol. 2004 Jun;77(918):479-87.
PMID: 15151968
Jones AK, Hintenlang DE, Bolch WE.
Tissue-equivalent materials for construction of
tomographic dosimetry phantoms in pediatric
radiology.
Med Phys. 2003 Aug;30(8):2072-81.
*Study Design types:
1=Systematic review or meta-analysis of randomized controlled trial
2=Randomized controlled trial
3=Nonrandomized controlled trial
4=Observational (a=cohort, b=cross-sectional, c=case-control study)
5=Non-experimental study
6=Expert opinion
7=General review article
Kaste SC
Corresponding data of other countries extracted from
UNSCEAR 2000 report or originating from literature, shows
significant differences in national radiological practices and a
very uneven distribution of patient doses amongst the world
population. Mean annual effective dose per head of
population varies by up to a factor of 60 between health care
level I and IV countries; by a factor of ~6 within health care
level I countries. Pojection radiography succeeded in reducing
dose consumption; CT and IR have given rise to significant
growth of patient exposure; IR can exceed thresholds for
deterministic radiation effects. Patient exposure also results
from misadministration and retakes of X-ray examinations,
usually not registered, and from technical failures of X-ray
facilities, causing significantly enhanced exposure times.
different concepts must be introduced for a better
understanding of the tradeoffs encountered when dealing with
digital radiography and ALARA. In addition, there are many
instances during the image acquisition/display/interpretation
process in which image quality and associated dose can be
compromised. This requires continuous diligence to quality
control and feedback mechanisms to verify that the goals of
image quality, dose and ALARA are achieved
Using a grid, ED increased with increasing object thickness
by a factor of 1.9 to 3.5. At equal voltages, the grid led to
significant image improvements, with SNRb and SNRd
increasing by 27% and 11%, respectively. SNRb and SNRd
are useful descriptors of the image quality in cardiac
angiography. Highest image quality was found with tube
voltages between 55 kV and 77 kV, independently of object
thickness.To minimize dose, the thickness of the copper filter
should be chosen to be as large as possible provided the tube's
power limit allows keeping the voltage below the upper limit.
In view of the substantial image improvement, the use of a
grid is recommended for all patients, even for newborns
For the child/adult TE materials, these same maximal
deviations of mu/rho and mu(en)/rho are from +1.5% to -3%
and from +3% to -3%, respectively. Simple calculations of xray fluence attenuation under narrow-beam geometry using a
66 kVp spectrum typical of newborn CR radiographs indicate
Reference Table NRSI 2007
Search parameters: 0-18 y/o children; ionizing radiation; imaging; past 10 y
PMID: 12945973
Buls N, Pages J, de Mey J, Osteaux M.
Evaluation of patient and staff doses during
various CT fluoroscopy guided interventions.
Health Phys. 2003 Aug;85(2):165-73.
PMID: 12938963
4
Buch B, Fensham R.
82
patients
phantom
To determine whether possible
radiation overdose to sensitive
structures in the head and neck
region occurs with orthodontic
radiographs
phantom
To quantify radiation risks from
medical exposures and formulate
corresponding dose-reduction
strategies.
Orthodontic radiographic procedures--how safe
are they?
SADJ. 2003 Feb;58(1):6-10.
PMID: 12705098
Staton RJ, Pazik FD, Nipper JC, Williams JL,
Bolch WE.
A comparison of newborn stylized and
tomographic models for dose assessment in
*Study Design types:
1=Systematic review or meta-analysis of randomized controlled trial
2=Randomized controlled trial
3=Nonrandomized controlled trial
4=Observational (a=cohort, b=cross-sectional, c=case-control study)
equivalent materials include
STES-NB (newborn soft tissue
substitute), BTES-NB (newborn
bone tissue substitute), LTES
(newborn as well as a child/adult
lung tissue substitute), STES
(child/adult soft tissue substitute),
and BTES (child/adult bone tissue
substitute)
To quantify and to evaluate both
patient and staff doses by direct
thermoluminescent dosimetry
during various clinical CT
fluoroscopy guided procedures.
5=Non-experimental study
6=Expert opinion
7=General review article
Kaste SC
that the tissue-equivalent materials presented here yield
estimates of absorbed dose at depth to within 3.6% for STESNB, 3.2% for BTES-NB, and 1.2% for LTES of the doses
assigned to reference newborn soft, bone, and lung tissue,
respectively
Median values were determined (data per procedure): patient
E (19.7 mSv), patient entrance skin dose (374 mSv), staff
entrance skin dose at eye level (0.21 mSv), thyroid (0.24
mSv), at the left hand (0.18 mSv), and at the right hand (0.76
mSv). The maximum recorded patient entrance skin dose
stayed well below deterministic threshold level of 2 Gy. Poor
correlation between both patient/staff doses and integrated
procedure mAs emphasizes the need for in vivo
measurements. CT fluoroscopy doses are markedly higher
than classic CT-scan doses and are comparable to doses from
other interventional radiological procedures. They
consequently require adequate radiation protection
management. An important potential for dose reduction exists
by limiting the fluoroscopic screening time and by reducing
the tube current (mA) to a level sufficient to provide adequate
image quality
In all cases the readings of each group of 3 TLDs did not vary
by more than 10% on either side of the mean readings. The
TLD readings were then converted by means of a conversion
factor to actual dose measurements. The doses to left and right
eyes and to the thyroid were respectively found to be 0,0151,
0,0222 & 0,0896 mSv for the pantomogram and 0,0351,
0,0183 & 0,0177 mSv for the cephalogram--an almost
insignificant dose in terms of the "background equivalent"
concept.
Sixteen separate radiographs were simulated for each model
at x-ray technique factors typical of newborn examinations:
chest, abdomen, thorax and head views in the AP, PA, left
LAT and right LAT projection orientation. For AP and PA
radiographs of the torso (chest, abdomen and thorax views),
Reference Table NRSI 2007
Search parameters: 0-18 y/o children; ionizing radiation; imaging; past 10 y
paediatric radiology.
Phys Med Biol. 2003 Apr 7;48(7):805-20.
PMID: 12701888
No authors listed
Review
To protect patients against
unnecessary exposure to ionising
radiation. It is organised in a
questions-and-answers format.
3000 pt
doses;
200 XR
To compare all aspects of
paediatric radiological practice at
two specialist and two nonspecialist centres.
Radiation and your patient: a guide for medical
practitioners.
Ann ICRP. 2001;31(4):5-31.
PMID: 12685757
Cook JV, Kyriou JC, Pettet A, Fitzgerald MC,
Shah K, Pablot SM.
Key factors in the optimization of paediatric Xray practice.
Br J Radiol. 2001 Nov;74(887):1032-40.
PMID: 11709469
*Study Design types:
1=Systematic review or meta-analysis of randomized controlled trial
2=Randomized controlled trial
3=Nonrandomized controlled trial
4=Observational (a=cohort, b=cross-sectional, c=case-control study)
5=Non-experimental study
6=Expert opinion
7=General review article
Kaste SC
the effective dose assessed for the tomographic model
exceeds that for the stylized model with per cent differences
ranging from 19% (AP abdominal view) to 43% AP chest
view. In contrast, the effective dose for the stylized model
exceeds that for the tomographic model for all eight lateral
views including those of the head, with per cent differences
ranging from 9% (LLAT chest view) to 51% (RLAT thorax
view). While organ positioning differences do exist between
the models, a major factor contributing to differences in
effective dose is the models' exterior trunk shape. In the
tomographic model, a more elliptical shape is seen thus
providing for less tissue shielding for internal organs in the
AP and PA directions, with corresponding increased tissue
shielding in the lateral directions. This observation is opposite
of that seen in comparisons of stylized and tomographic
models of the adult.
The text provides ample information on opportunities to
minimise doses, and therefore the risk from diagnostic uses of
radiation. This objective may be reached by avoiding
unnecessary (unjustified) examinations, and by optimising the
procedures applied both from the standpoint of diagnostic
quality and in terms of reduction of the excessive doses to
patients. Optimisation of patient protection in radiotherapy
must depend on maintaining sufficiently high doses to
irradiated tumours, securing a high cure rate, while protecting
the healthy tissues to the largest extent possible. Problems
related to special protection of the embryo and fetus in the
course of diagnostic and therapeutic uses of radiation are
presented and practical solutions are recommended. This issue
of the Annals of the ICRP also includes a brief report
concerning Diagnostic Reference Levels in medical imaging:
Review and additional advice.
While all radiographs were found to be diagnostically
acceptable, major differences in technique were evident,
reflecting the disparity in experience between staff at the
specialist and non-specialist centres. The large number of suboptimum films encountered at the latter suggests that there is
a need for specific training of less experienced radiographic
and clinical staff.
Reference Table NRSI 2007
Search parameters: 0-18 y/o children; ionizing radiation; imaging; past 10 y
Huda W, Chamberlain CC, Rosenbaum AE,
Garrisi W.
23
infants
23
‘adult’
Radiation doses to infants and adults undergoing
head CT examinations.
Med Phys. 2001 Mar;28(3):393-9.
PMID: 11318321
Compare the radiation doses of
infant patients aged no more than
two years old, with those of
"adults" defined as any patient
whose weight was greater than 40
kg. Data were obtained for 23
infants, and an equal number of
"adults," who underwent CT head
examinations between May 1997
and March 1998.
No significant correlation between patient effective dose and
patient mass for either the infant (r2 = 0.12) or the "adult"
group of patients (r2= 0.02). Infant doses varied much more
than "adult" doses, primarily because of a wider range of xray technique factors selected and secondarily due to the
variation in infant head size. Observed variability in
computed radiation dose parameters indicates that it should be
possible to reduce infant doses routinely in head CT
examinations without any adverse effect on diagnostic
imaging performance. For such routine head CT scans,
average dose reduction for infants weighing between 4 and 8
kg would be expected to range between 40% and 60%.
Conversion factors, which relate the kerma-area product to
effective dose, have been estimated for paediatric cardiac xray angiography. Monte Carlo techniques have been used to
calculate the conversion factors for a wide range of projection
angles for children of five ages and for adults. Correction
factors are provided so that conversion factors can be adjusted
for different tube potentials and filtrations.
Commentary/Review
An investigation requiring use of ionising radiation can be
justified by showing that its benefits are likely to exceed its
risks. Risks can be estimated from effective dose by using
system recommended by International Commission on
Radiological Protection. Benefits of investigations in
paediatric radiology are currently unquantified. We can
assume some tests have potential benefits so large that further
evaluation is unnecessary. Others have maximum potential
benefit so low that they can be discarded. For most
investigations, however, research into the magnitude of
benefit to the patient is required in order to establish that it is
greater than the magnitude of the radiation risk.
Studies of seizures, primarily those without known
precipitating cause, also exhibit a radiation effect on those
individuals exposed in the first 16 weeks after ovulation.
Cellular and molecular events that subtend these
abnormalities are still largely unknown although some
progress toward an understanding has occurred. For example,
magnetic resonance imaging of the brain of some of the
Schmidt PW, Dance DR, Skinner CL, Smith IA,
McNeill JG.
Conversion factors for the estimation of effective
dose in paediatric cardiac angiography.
Phys Med Biol. 2000 Oct;45(10):3095-107.
PMID: 11049190
Roebuck DJ.
Risk and benefit in paediatric radiology.
Pediatr Radiol. 1999 Aug;29(8):637-40.
PMID: 10415195
7
Schull WJ, Otake M.
7
Review
Review
Cognitive function and prenatal exposure to
ionizing radiation.
Teratology. 1999 Apr;59(4):222-6. Review.
PMID: 10331523
*Study Design types:
1=Systematic review or meta-analysis of randomized controlled trial
2=Randomized controlled trial
3=Nonrandomized controlled trial
4=Observational (a=cohort, b=cross-sectional, c=case-control study)
Kaste SC
5=Non-experimental study
6=Expert opinion
7=General review article
Reference Table NRSI 2007
Search parameters: 0-18 y/o children; ionizing radiation; imaging; past 10 y
Njeh CF, Fuerst T, Hans D, Blake GM, Genant
HK.
7
Radiation exposure in bone mineral density
assessment.
Appl Radiat Isot. 1999 Jan;50(1):215-36. Review.
PMID: 10028639
Goldberg MS, Mayo NE, Levy AR, Scott SC,
Poitras B.
4b
Adverse reproductive outcomes among women
exposed to low levels of ionizing radiation from
diagnostic radiography for adolescent idiopathic
scoliosis.
Epidemiology. 1998 May;9(3):271-8.
PMID: 9583418
*Study Design types:
1=Systematic review or meta-analysis of randomized controlled trial
2=Randomized controlled trial
3=Nonrandomized controlled trial
4=Observational (a=cohort, b=cross-sectional, c=case-control study)
Review
Present an overview of current
techniques for bone mineral
density (BMD) measurements. In
the second section we discuss the
radiation doses incurred in BMD
measurements by patients and
methods for reducing patient and
staff radiation exposure are given.
Estimated risk for unsuccessful
attempts at pregnancy,
spontaneous abortions, low
birthweight (<2,500 gm),
congenital malformations, and
stillbirths according to dose to the
ovaries
5=Non-experimental study
6=Expert opinion
7=General review article
Kaste SC
mentally retarded survivors has revealed a large region of
abnormally situated gray matter, suggesting an abnormality in
neuronal migration, but cell killing could also contribute
importantly to the effects on cognitive function that have been
seen. Retardation of growth in stature observed in individuals
exposed in first and second trimesters of pregnancy suggests
that development of atypically small head size, without
conspicuously impaired cognitive function, may reflect
generalized growth retardation.
Studies of radiation dose to patient from DXA confirms that
patient dose is small (0.08-4.6 muSv) compared to that given
by many other investigations involving ionizing radiation. Fan
beam technology with increased resolution has resulted in
increase patient dose radiation dose (6.7-31 muSv) but this is
still relatively small. Carrying vertebral morphometry using
DXA also incurs less radiation dose (< 60 muSv) than
standard lateral radiographs QCT has radiation dose (25-360
muSv) comparable to simple radiological examination such as
chest X-ray but lower than imaging CT. Radiation dose from
other techniques such as RA and SXA are in the same order
of magnitude as pencil beam DXA. For pencil beam DXA
and SXA systems the time average dose to staff from scatter
is very low even with the operator sitting as close as 1 m from
the patient during measurement. However the scatter dose
from fan beam DXA systems is considerable higher and
approaches limits set by regulator bodies for occupational
exposure.
Risks in the adolescent idiopathic scoliosis cohort were higher
than in the reference group for unsuccessful attempts at
pregnancy [adjusted odds ratio (OR) = 1.33; 95% confidence
interval (CI) = 0.84-2.13], spontaneous abortions (OR = 1.35;
95% CI = 1.06-1.73), and congenital malformations (OR =
1.20; 95% CI = 0.78-1.84), but the odds ratios did not
increase monotonically by dose to the ovaries. There were
fewer stillbirths (OR = 0.38; 95% CI = 0.15-0.97) and lowbirthweight infants in the adolescent idiopathic scoliosis
cohort (OR = 0.84; 95% CI = 0.59-1.21). Nevertheless, when
the analysis of low birthweight was restricted to the
adolescent idiopathic scoliosis cohort, the adjusted odds ratios
Reference Table NRSI 2007
Search parameters: 0-18 y/o children; ionizing radiation; imaging; past 10 y
Ernst M, Freed ME, Zametkin AJ.
7
Health hazards of radiation exposure in the
context of brain imaging research: special
consideration for children.
J Nucl Med. 1998 Apr;39(4):689-98. Review.
PMID: 9544683
*Study Design types:
1=Systematic review or meta-analysis of randomized controlled trial
2=Randomized controlled trial
3=Nonrandomized controlled trial
4=Observational (a=cohort, b=cross-sectional, c=case-control study)
Review
To provide information on health
and biological effects of low-dose
radiation to help institutional
review boards and investigators
make educated assessments of the
risks of low-level radiation
exposure involved in research,
particularly in children.
5=Non-experimental study
6=Expert opinion
7=General review article
Kaste SC
were found to increase by quartiles of dose (median dose of
0.69 cGy): 1; 1.43 (95% CI = 0.54-3.90); 2.24 (95% CI =
0.89-5.94); and 2.34 (95% CI = 1.02-5.62). We also found
that the adjusted mean birthweight decreased with increasing
dose by 37.6 gm per cGy (standard error = 23.5 gm per cGy).
first study in which an association with birthweight has been
found with diagnostic radiography.
Risk of increased rates of cancer after low-level radiation
exposure is not supported by population studies of health
hazards from exposure to background radiation, radon in
homes, radiation in the workplace or radiotherapy. Compared
to frequency of daily spontaneous genetic mutations,
biological effect of low-level radiation at cellular level seems
extremely low. Potentiation of cellular repair mechanisms by
low-level radiation may result in protective effect from
subsequent high-level radiation. Studies approved by
institutional review boards in the U.S. that involve the
exposure of healthy normal children to ionizing radiation
were reviewed. Health risks from low-level radiation could
not be detected above the "noise" of adverse events of
everyday life. No data found that demonstrated higher risks
with younger age at low-level radiation exposure.