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IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology. RADIATION PROTECTION IN DIAGNOSTIC AND INTERVENTIONAL RADIOLOGY. L 21: Optimization of Protection in Pediatric Radiology. Introduction.

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radiation protection in diagnostic and interventional radiology
IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology

RADIATION PROTECTION INDIAGNOSTIC ANDINTERVENTIONAL RADIOLOGY

L 21: Optimization of Protection in Pediatric Radiology

introduction
Introduction
  • Good radiation protection policy in pediatric radiology is essential.
  • International guidelines are available to assist in optimization of image quality and radiation dose in pediatric imaging

21: Optimization of Protection in Pediatric Radiology

topics
Topics
  • General recommendations
  • Quality criteria for radiographic images (EUR-16261 document)
  • Recommendations for X Ray equipment and rooms for pediatric radiology
  • References

21: Optimization of Protection in Pediatric Radiology

overview
Overview
  • To become familiar with the principles of radiation protection in pediatric radiology, the X Ray systems to be used and the principles of optimization and quality control

21: Optimization of Protection in Pediatric Radiology

part 21 optimization of protection in pediatric radiology
IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology

Part 21: Optimization of Protection in Pediatric Radiology

Topic 1: General recommendations for pediatric radiology

general recommendations for pediatric radiology
General recommendations for pediatric radiology
  • General, equipment and installation considerations
    • The generator should provide short exposure times (3 milliseconds) with sufficient power to obtain appropriate exposure
    • The generator should be high frequency to improve the accuracy and reproducibility of exposures
    • Automatic exposure control (AEC) devices should be used with caution in pediatrics
    • AEC should have specific technical requirements for pediatrics

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology7
General recommendations for pediatric radiology
  • Careful manual selection of exposure factors usually results in lower doses
  • X Ray rooms for pediatrics should be designed for improving the child’s cooperation (control panel within easy reach, etc.)
  • Fast screen-film combinations or digital radiography have advantages (reduction of dose) and limitations
  • Low-absorbing materials in cassettes, table tops, etc. are important in pediatrics radiology

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology8
General recommendations for pediatric radiology
  • Many examinations can be carried out without antiscatter grids (small volume irradiated, less scatter), thereby reducing the dose to the patient by a factor of two or more
  • Antiscatter grids for pediatrics should have specific technical requirements
  • Antiscatter grid should be removable in pediatric equipment, particularly fluoroscopic systems
  • Image intensifiers should have high conversion factors for reducing patient dose in fluoroscopic systems

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology9
General recommendations for pediatric radiology
  • Specific kV-mA dose rate curves for automatic brightness control (ABC) should be used in fluoroscopic systems for pediatrics.
  • There should be a “floor” of 70 kV on fluoro
  • It is preferable not to use the ABC unless there is an automatic cut-off device.
  • Specific protocols should be used for pediatric patients in CT, e.g., lower mAs, lower kVp, etc.

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology10
General recommendations for pediatric radiology
  • Consider the advantages and disadvantages of under-couch and over-couch fluoroscopy units
  • Pulsed fluoroscopy allows for significant patient dose reduction
  • Digital equipment and the use of frame-grab (Last image hold, or LIH) techniques will result pediatric dose reduction
  • The cine playback (digital) and video playback (digital or conventional fluoroscopy) in screening examinations may allow patient dose reductions
  • Additional tube filtration will reduce pediatric dose with no impact on image contrast

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology11
General recommendations for pediatric radiology
  • Reduction of exposure
    • Repeat analysis should be carried out as part of the QC program. Feedback should be provided to the radiographers
    • Immobilization can reduce the repeat rate
    • Immobilization devices should be used. The role of simple aids such as tape, sponge wedges, and sand bags should also be considered.

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology12
General recommendations for pediatric radiology
  • Short exposure times can improve image quality and reduce the number of repeat films
  • The use of mobile X Ray units for pediatrics should be restricted due to the difficulty in obtaining short exposure times
  • Radiographers should have specific training in pediatric radiology
  • Gonadal protection is important in pediatric radiology. Several sizes and types should be available

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology13
General recommendations for pediatric radiology
  • Collimation is important. Every image should be collimated to the body part of interest.
  • The correct patient positioning and collimation is important in pediatrics, particularly for excluding the gonads from the direct beam
  • It is important to establish whether adolescent girls might be pregnant when abdominal examinations are contemplated

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology14
General recommendations for pediatric radiology
  • Motion is a major problem in children and could require specific adjustment of radiographic techniques
  • Proper consultative relationship between the referring physician and the radiologist is especially important in pediatrics
  • Protocols and diagnostic pathways should be promoted

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology15
General recommendations for pediatric radiology
  • Some radiological examinations are of questionable value in children (e.g., follow-up chest radiographs in simple pneumonia, abdominal radiographs in suspected constipation, etc.)
  • The repetition of a radiological examination in pediatrics should be at the discretion of the radiologist.

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology16
General recommendations for pediatric radiology
  • Appropriate projections for minimizing dose in high risk tissues should be used (PA projections should replace AP where possible for spinal examinations)
  • Additional filters should be available to enable them to be easily changed (1 mm Al; 0.1 and 0.2 mm Cu should be available).
  • Shaped filters are available to reduce dose and improve image quality for full spine radiographs

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology17
General recommendations for pediatric radiology
  • Dedicated pediatric room or complete sessions dedicated to pediatric radiography should be available
  • Experienced staff who can obtain the child’s confidence and cooperation in a secure and child-friendly environment are of paramount importance in reducing radiation doses in pediatrics
  • Specific referral criteria for pediatric radiology should be available, e.g., for head injury where the incidence of injury is low

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology18
General recommendations for pediatric radiology
  • Referral criteria for all X Ray examinations of children should be established, especially those which may be age-related, e.g., scaphoid not ossified below age of 6 years; nasal bones cartilaginous below age of 3 years
  • Higher kV techniques should be used when possible in order to reduce pediatric doses.
  • Long focus patient distances could be used to minimize patient entrance dose (with the compromise of appropriate exposure times)

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology19
General recommendations for pediatric radiology
  • Fluoroscopy should not be used for patient positioning.
  • Audit and quality control is essential for optimizing image quality and patient dose

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology20
General recommendations for pediatric radiology

Risk factors

  • Pediatric examinations require special consideration in the justification process since children are at greater risk of incurring stochastic effects,
  • The benefit of high dose, high risk examinations (e.g., computed tomography, IVU, etc.) should be carefully weighed against the increased risk

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology21
General recommendations for pediatric radiology

Risk factors

  • Longer life expectancy in children means a greater potential for manifestation of possible harmful effects of radiation
  • Radiation doses used to examine young children should generally be much lower than those employed in adults
  • Risk factors for cancer induction in children is between 2 and 3 times higher than for adults

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology22
General recommendations for pediatric radiology

Patient dosimetry – Diagnostic Reference Levels (DRLs)

  • Measuring patient doses in pediatrics presents special difficulties (small values)
  • Dosimetric techniques used in pediatrics should be specifically adapted
  • Patient doses are related to patient size

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology23
General recommendations for pediatric radiology
  • DRLs in pediatrics should be related to patient size, not age
  • DRLs presently available for pediatrics are limited (See EUR-16261 and NCRP Report on DRLs, available 2012)

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology24
General recommendations for pediatric radiology

Protection of personnel and parents

  • Parents can cooperate in the radiological examination of their children if they are duly informed and protected
  • Parents’ exposure in this situation can be considered as a medical exposure but optimization criteria must be applied

21: Optimization of Protection in Pediatric Radiology

general recommendations for pediatric radiology25
General recommendations for pediatric radiology
  • Parents or helpers should be duly informed and should know exactly what is required of them
  • Pregnant women should not be allowed to help during pediatric examinations
  • Lead aprons and lead gloves (if the hands are near the direct radiation field) should be used

21: Optimization of Protection in Pediatric Radiology

icrp isr smart message for pediatrics
ICRP-ISR “smart” message for pediatrics

21: Optimization of Protection in Pediatric Radiology

part 21 optimization of protection in pediatric radiology27
IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology

Part 21: Optimization of protection in Pediatric Radiology

Topic 2: Quality criteria for radiographic images (EUR document)

slide28
European Guidelines on Quality Criteria for Diagnostic Radiographic Images in Paediatrics, July 1996.

EUR 16261 EN

Free PDF version available at:

http://www.cordis.lu/fp5-euratom/src/lib_docs.htm

21: Optimization of Protection in Pediatric Radiology

criteria related to images
Criteria related to images
  • The Image Criteria for pediatric patients presented for a particular type of radiograph are those deemed necessary to produce an image of standard quality
  • No attempt has been made to define acceptability for particular clinical indications
  • The image criteria allow an immediate evaluation of the image quality of the respective radiograph. They are appropriate for the most frequent requirements of radiographic imaging of pediatric patients

21: Optimization of Protection in Pediatric Radiology

criteria related to images32
Criteria related to images
  • The anatomical features and body proportions vary due to the developmental process in infancy, childhood and adolescence
  • They are different in the respective age groups and are distinct from those of a mature patient
  • The Guidelines presuppose knowledge of the changing radiographic anatomy of the developing child.
  • The term “consistent with age” indicates that the respective image criteria essentially depend on the age of the patient

21: Optimization of Protection in Pediatric Radiology

criteria related to images33
Criteria related to images
  • The smaller body size
  • The age dependent body composition
  • The lack of co-operation and many functional differences (e.g., higher heart rate, faster respiration, inability to stop breathing on command, increased intestinal gas, etc.)
  • Prevent the production of radiographic images in pediatric patients to which standard adult image criteria can be applied

21: Optimization of Protection in Pediatric Radiology

criteria related to images34
Criteria related to images
  • Correct positioning of pediatric patients will be more difficult than in co-operative adult patients
  • Use of auxiliary devices is essential for effective immobilization
  • Sufficient skill and experience of the imaging staff, and ample time for the particular examination, are necessary to obtain quality images in infants and younger children

21: Optimization of Protection in Pediatric Radiology

criteria related to images35
Criteria related to images
  • Incorrect positioning is the most frequent cause of inadequate image quality in pediatric radiographs
  • Image criteria for the assessment of adequate positioning (symmetry and absence of tilting etc) are much more important in pediatric imaging than in adults
  • A lower level of image quality than in adults may be acceptable for certain clinical indications

21: Optimization of Protection in Pediatric Radiology

criteria related to images36
Criteria related to images
  • A lower quality image cannot be justified unless this has been part of optimization and is associated with a lower radiation dose
  • The fact that the X Ray was taken from of non-cooperative pediatric patient (anxious, crying, heavily resisting) is not an excuse for producing an inferior quality image which is often associated with excessive dose

21: Optimization of Protection in Pediatric Radiology

criteria for radiation dose to the patient
Criteria for Radiation Dose to the Patient
  • DRLs are expressed as the entrance surface dose for a “standard sized” pediatric patient
  • DRLs are only available for the most frequently performed types of examinations for which sufficient data is available

21: Optimization of Protection in Pediatric Radiology

criteria for radiation dose to the patient38
Criteria for Radiation Dose to the Patient
  • Some form of dose measurement is required in order to audit patient doses
  • This requires representative sampling of the patient population
  • A number of dose measurement methods are described in the European Guidelines

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance
General principles associated with good imaging performance

Image Annotation

  • The patient identification, date of examination, position markers, and name of the facility must be present and legible on the image
  • These annotations should not obscure the diagnostically relevant regions of the image
  • Identification of the individual carrying out the examination should be on the film

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance40
General principles associated with good imaging performance

Quality Control of X Ray Imaging Equipment

  • Quality control programs should be in use in every medical X Ray facility and should monitor image quality and patient dose
  • Operating levels and control limits should be established by a medical physicist

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance41
General principles associated with good imaging performance

Low Attenuation Materials

  • Recent developments in materials for cassettes, grids, tabletops and front plates of film-changers using carbon fiber and some new plastics enable significant reduction in patient doses
  • This reduction is most significant in the radiographic voltage range recommended in pediatric patients and may reach 40%. Use of these materials should be encouraged

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance42
General principles associated with good imaging performance

Patient Positioning and Immobilization

  • Patient positioning must be exact whether or not the patient co-operates.
  • For infants, toddlers, and younger children immobilization devices, will help to assure that:
    • the patient does not move
    • the beam can be centered correctly
    • the film is obtained in the proper projection
    • accurate collimation limits the field size exclusively to the required area
    • shielding of the remainder of the body is possible.

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance43
General principles associated with good imaging performance

Patient Positioning and Immobilization

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance44
General principles associated with good imaging performance

Patient Positioning and Immobilization

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance45
General principles associated with good imaging performance

Patient Positioning and Immobilization

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance46
General principles associated with good imaging performance

Patient Positioning and Immobilization

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance47
General principles associated with good imaging performance

Patient Positioning and Immobilization

  • Immobilization devices must be easy to use, and their application atraumatic to the patient.
  • Their usefulness should be explained to the accompanying parent(s).
  • Radiological staff members should only hold a patient under exceptional circumstances
  • Examination time allocation must include the time to explain the procedure not only to the parents but also to the child

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance48
General principles associated with good imaging performance

Field Size and X Ray Beam Limitation

  • Inappropriate field size is the most important fault in pediatric imaging
  • A field which is too small will exclude potentially important information
  • A field which is too large will not only reduce image contrast by increasing the amount of scattered radiation but also result in unnecessary radiation exposure outside the area of interest

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance49
General principles associated with good imaging performance

Field Size and X Ray Beam Limitation

  • Correct beam limitation requires proper knowledge of the external anatomical landmarks by the radiographer
  • These differ with the age of the patient according to the varying proportions of the developing body.
  • In addition, the size of the field of interest depends much more on the nature of the underlying disease in infants and younger children than in adults

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance50
General principles associated with good imaging performance

Field Size and X Ray Beam Limitation

  • A basic knowledge of pediatric pathology is required for radiographers to assure proper beam limitation
  • The acceptable minimal field size is set by the recognizable anatomical landmarks for specific examinations

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance51
General principles associated with good imaging performance

Field Size and X Ray Beam Limitation

  • Beyond the neonatal period, the tolerance for maximal field size should be less than 2 cm greater than the minimal
  • In the neonatal period, the tolerance level should be reduced to 1.0 cm at each edge

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance52
General principles associated with good imaging performance

Field Size and X Ray Beam Limitation

  • In pediatric patients, evidence of the field limits should be apparent by clear areas of the exposed image
  • Beam-limiting devices which automatically adjusting to the cassette size are inappropriate for pediatric patients
  • Discrepancies between the radiation beam and the light beam alignment must be avoided by regular assessment

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance53
General principles associated with good imaging performance

Additional filtration

  • The soft part of the radiation spectrum which is absorbed in the patient is useless for the production of the radiographic image and contributes unnecessarily to the patient dose
  • Part of it is eliminated by the filtration of the tube, tube housing, collimator etc., but this is insufficient
  • Most tubes have a minimum filtration of 2.5 mm Al
  • Additional filtration can further reduce unproductive radiation and thus patient dose
  • 1 to 2 mm, or more, of aluminum can be added without reducing contrast

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance54
General principles associated with good imaging performance

Additional filtration

  • For pediatric patients, total radiation dose must be kept low, particularly when high speed screen-film systems or image intensified techniques are used
  • Not all generators allow the short exposure times that are required for higher kV technique
  • Low radiographic voltage is frequently used for pediatric patients. This results in comparatively higher patient doses.

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance55
General principles associated with good imaging performance

Additional filtration

  • Adequate additional filtration allows the use of higher radiographic voltage with the shortest available exposure times, overcoming the limited short exposure time capability
  • This makes the use of high speed screen-film systems and digital radiography possible

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance56
General principles associated with good imaging performance

Protective Shielding

  • For all examinations of pediatric patients, the examples for “Good Radiographic Technique” include standard equipment of lead-rubber shielding of the body in the immediate proximity of the diagnostic field

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance57
General principles associated with good imaging performance

Protective Shielding

  • For exposures of 70 - 80 kV, maximum gonadal dose reduction of about 30 to 40% can be obtained by shielding with 0.25 mm lead equivalent rubber immediately at the field edge
  • However, this is only true when the protection is placed correctly at the field edge

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance58
General principles associated with good imaging performance

Protective Shielding

  • The gonads in "hot examinations", i.e., when they lie within or close (nearer than 5 cm) to the primary beam, should be protected whenever possible without impairing necessary diagnostic information
  • Various sized gonad shield should be available

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance59
General principles associated with good imaging performance

Protective Shielding

  • By properly adjusting male gonad shields the absorbed dose in the testes can be reduced by up to 95%
  • In girls, shadow masks within the diaphragm of the collimator are as efficient as direct shields. They can be positioned more easily and do not slip as easily as with contact shields
  • When shielding of the female gonads is effective, the reduction of the absorbed dose in the ovaries will be about 50%

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance60
General principles associated with good imaging performance

Protective Shielding

  • There is no reason to include the male gonads within the primary radiation field for radiographs of the abdomen
  • The same applies, usually, for films of the pelvis and micturating cystourethrography. The testis should be protected with male gonad shields, and kept outside the field
  • Gonad protection is not possible for females for abdominal examinations

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance61
General principles associated with good imaging performance

Protective Shielding

  • In practice, the great majority of pelvic films show that female gonad protection is completely ineffective
  • There are justifiable reasons for omitting gonad protection for pelvic films in girls, e.g., trauma, incontinence, abdominal pain, etc.

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance62
General principles associated with good imaging performance

Protective Shielding

  • The eyes should be shielded for X Ray examinations involving high absorbed doses to the eyes, e.g., for conventional tomography of the petrous bone, when patient cooperation permits
  • The absorbed dose to the eyes can be reduced by 50% - 70%
  • In imaging of the skull the use of PA-projection rather than the AP-projection can reduce the absorbed dose in the eyes by 95%

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance63
General principles associated with good imaging performance

Protective Shielding

  • PA-projection, therefore, should be preferred as soon as patient age and co-operation permit prone or erect positioning
  • Developing breast tissue is particularly sensitive to radiation, consequently exposure must be limited
  • The 16 year old’s breast tissue is 16 times more sensitive to cancer induction that the 40 year old’s breast tissue.
  • The most effective method is by using the PA-projection, rather than the AP

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance64
General principles associated with good imaging performance

Protective Shielding

  • While this is well accepted for chest examinations, the greatest risk is during spinal examinations, and here PA examinations must replace AP
  • It should also be remembered that thyroid tissue should be protected, whenever possible, e.g., during dental and facial examinations, and are protected in PA projections

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance65
General principles associated with good imaging performance

Radiographic Exposure Conditions

  • Knowledge and correct use of appropriate radiographic technique factors, e.g., radiographic voltage, nominal focal spot size, filtration, source-to-image distance, due to their impact on patient dose and image quality
  • Permanent characteristics of the equipment such as total tube filtration and grid specifications should also be taken into consideration

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance66
General principles associated with good imaging performance

Automatic Exposure Control

  • Adult patients vary in size, but their variation is minimal compared to the range in pediatric patients from premature infants, weighing considerably less than a thousand grams, to adolescents approaching 70 kg, or more
  • AEC is helpful in obtaining appropriately exposed radiographs in pediatric imaging

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance67
General principles associated with good imaging performance

Automatic Exposure Control

  • Many of the AEC systems commonly available are not satisfactory
  • They have relatively large and fixed ionization chambers. Neither their size, shape, nor position is appropriate for the many variations of body size and proportion in pediatric patients

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance68
General principles associated with good imaging performance

Automatic Exposure Control

  • AEC use may be associated with the use of the grid (where the grid is not removable) which is frequently unnecessary
  • Optimal AEC systems must provide a method to compensate for different speed image receptors.

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance69
General principles associated with good imaging performance

Automatic Exposure Control

  • Image receptors and AEC chambers are energy dependent, particularly at lower radiographic voltage. Adequate compensation must be provided
  • AECs increase the minimal exposure times
  • All these factors must be considered when AECs are used in pediatric patients

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance70
General principles associated with good imaging performance

Automatic Exposure Control

  • Specially designed pediatric AECs have a small, mobile detector for use behind a cassette (without lead backing)
  • The AEC position can be selected with respect to the most important region of interest
  • Positioning is critical and difficult

21: Optimization of Protection in Pediatric Radiology

general principles associated with good imaging performance71
General principles associated with good imaging performance

Automatic brightness control

  • Automatic brightness control (ABC) must be switched off during fluoroscopic examinations where there are relatively large areas of contrast material, to avoid excessive dose rates, e.g., full bladders

21: Optimization of Protection in Pediatric Radiology

guidance on implementation of quality criteria
Guidance on implementation of quality criteria
  • Quality Criteria are presented in the European Guidelines for a number of selected radiographic projections used in the course of routine types of X Ray examination
  • They apply to pediatric patients with the usual presenting symptoms for the type of examination being considered
  • They are to be used by radiologists, radiographers, and medical physicists as a check on the routine performance of the entire imaging process

21: Optimization of Protection in Pediatric Radiology

guidance on implementation of quality criteria73
Guidance on implementation of quality criteria
  • The Quality Criteria cannot be applied to all cases
  • A lower level of image quality may be acceptable for certain clinical indications—

Ideally this should be associated with lower patient dose.

21: Optimization of Protection in Pediatric Radiology

guidance on implementation of quality criteria74
Guidance on implementation of quality criteria

Under no circumstances should an image which fulfils all clinical requirements

but does not meet all image criteria ever be repeated

21: Optimization of Protection in Pediatric Radiology

diagnostic reference levels in pediatrics
Diagnostic Reference Levels in Pediatrics

Examples of Diagnostic Reference Levels in Pediatrics, for standard five-year-old patients, expressed in entrance surface dose per image, for single views (from EUR-16261)

21: Optimization of Protection in Pediatric Radiology

diagnostic reference levels in pediatrics78
Diagnostic Reference Levels in Pediatrics

Examples of Diagnostic Reference Levels in Pediatrics, for standardfive-year-old patients, expressed in entrance surface dose per image,for single views (from EUR-16261)

21: Optimization of Protection in Pediatric Radiology

part 14 1 optimization of protection in pediatric radiography
IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology

Part 14.1: Optimization of Protection in Pediatric Radiography

Topic 3: Recommendations for X Ray room and equipment

recommendations for x ray room and equipment for pediatrics
Recommendations for X Ray room and equipment for pediatrics
  • Visibility of the patient and easy audio communication from the control panel
  • High frequency generators of 600-800 mA with linearity from 50 to120 kV
  • Exposures of 3 ms should be possible. AEC devices should be specifically adapted
  • Different control for the anode rotation and exposure (specially important for chest examinations to avoid respiratory movement)

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recommendations for x ray room and equipment for pediatrics81
Recommendations for X Ray room and equipment for pediatrics
  • Low absorption materials and plastic cassette fronts should be used
  • Antiscatter grid should be removable
  • Grid motion should be rapid to avoid grid artifacts at short exposure times.
  • A 15-cm Image intensifier (I.I.) or flat panel fluoroscopic system is an appropriate size for pediatrics. Larger sizes or multi-mode systems are not needed.

21: Optimization of Protection in Pediatric Radiology

recommendations for x ray room and equipment to be used in pediatrics
Recommendations for X Ray room and equipment to be used in pediatrics
  • The use of additional x-ray beam filtration significantly reduces patient dose
  • Mobile X Ray system for pediatrics should have the high output in order to allow for short exposure times
  • Immobilization devices should be available in pediatric rooms

21: Optimization of Protection in Pediatric Radiology

summary
Summary
  • Particular attention should be paid to technical specifications of X Ray equipment and protocols used in pediatric imaging.
  • Radiologists and radiographers should be specifically trained for pediatric imaging.
  • Increased sensitivity for carcinogenesis of pediatric patients should be taken into account when any decisions are made about equipment and protocols

21: Optimization of Protection in Pediatric Radiology

references
References
  • European guidelines on quality criteria for diagnostic radiographic images in pediatrics, EUR 16261 report, (Luxembourg, EC), 1996. http://www.e-radiography.net/regsetc/European_guide_children_extract.pdf
  • ICRP Publication 34, Protection of the Patient in Diagnostic Radiology. Annals of the ICRP (2/3) 1982.
  • NCRP 68. Radiation protection in pediatric radiology, 1981.
  • Guidelines on education and training in radiation protection for medical exposures. Radiation Protection 116. European Commission 2000. Available at: http://europa.eu.int/comm/environment/radprot

21: Optimization of Protection in Pediatric Radiology

references85
References
  • Guidance on diagnostic reference levels (DRLs) for medical exposures. Radiation Protection 109. European Commission 1999. Available at: http://europa.eu.int/comm/environment/radprot
  • Rational use of diagnostic imaging in pediatrics. WHO, 1987.
  • Diagnostic reference levels for adult and pediatric patients, National Council on Radiation Protection and Measurement (NCRP), Bethesda, MD. In press (available 2012)

21: Optimization of Protection in Pediatric Radiology

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