Radiological protection in paediatric diagnostic and interventional radiology

Page/Line

Comment

4/

Introduction

The fact that this ICRP publication focuses on radiation protection for CHILDREN is not mentioned until page 4 paragraph (4). We therefore suggest deleting the first three paragraphs of the introduction entirely (as they are not relevant for this ICRP report) and starting the introduction as follows (slightly altered):

"Diagnostic radiological examinations carry HIGH risk per unit of radiation dose for the development of cancer in infants and children compared to adults."

4/54

The following should be added after the quotation of Brenner (Brenner, et al. 2007) in former paragraph (6):
"A recent study revealed that the number of CT scans performed on pediatric patients in the U.S. has increased fivefold over a 13-year period ending in 2008 (Larson, et al. 2011).”

Larson D.B., Johnson L. W., Schnell, B. M., Goske, M. J., Salisbury S. R., & Forman H. P., 2011. Rising use of CT in child visits to the emergency department in the United States, 1995-2008, Radiology 259, 793-801.

7/135-138

In order to highlight the difference to the use of an effective dose, it should be inserted that risk estimates depend on the mean absorbed dose /equiv. dose, for example:

For these reasons, risk assessment for medical uses of ionising radiation is best evaluated using appropriate risk values estimates, depending on mean absorbed dose or equivalent dose, for the individual tissues at risk, and for the age and sex distribution (and health status if known) of the individuals undergoing the medical procedures (ICRP 103, 2007)."

10/211-212

The uses this statement refers to should be clearly stated here.

"The probability of such effects is increased when ionising radiation is used in medical therapeutic or interventional procedures."

14/318

WHO report 757 should be included in chapter 3.1 as an additional reference.

World Health Organisation – Study Group, 1987, Rational use of diagnostic imaging in paediatrics. WHO Technical Report Series 757, Geneva.

17/403

Horwitz et al. should be included as a reference for checking that X-ray beams and light beams are coincident:

"…light beam localization system (Horwitz, et al., 1993)"

Horwitz A.E., Schweighofer-Berberich K., Schneider K., Kohn M.M., Bakowski C., Stein E., Freidhof C., Fendel H., 1993. Selected image quality parameter in a survey using a test phantom in radiological departments and offices in the FRG. Radiat. Protect. Dosim. 49, 79-82.

17/418-420

We recommend indicating 0.2 mm Cu as an additional filter, as it is generally used.

17/421

As there is also generator pulsing we propose deleting the following:

"…specially grid controlled, last image hold…"

18/439

We suggest the following change:

"in a range of institutions"à "in more than 100 childrens hospitals headed by paediatric radiologists (Schneider, et al. 1992; Schneider, et al. 1998; Perlmutter, et al, 1998; )"

Schneider K., Fendel H., Bakowski C., Stein E., Kohn M.M., Kellner M, Schweighofer K., Cartagena G., Padovani R., Panzer W., Scheurer C., Wall B.F.,1992. Results of a Dosimetry Study in the European Community on Frequent X-ray Examinations in Infants. Radiat. Protect. Dosimetry 43, 31-36.

Schneider K., Kohn M.M., Ernst G., 1998. The derivation of reference dose values to chest X-rays in paediatric radiography 80, 199- 202.

Perlmutter N., Arthur R., Beluffi G., Cook V., Horwitz A.E., Kramer P., Montagne J.P., Thomas P. Schneider K., 1998. The quality criteria for diagnostic radiographic images in paediatrics. Radiat. Protect. Dosimetry 80, 45-48.

20/471

Delete (Kohn 1996) in Table 3 and add the European Guidelines as well as the following two publications

Schneider K., Fendel H., Bakowski C., Stein E., Kohn M.M., Kellner M, Schweighofer K., Cartagena G., Padovani R., Panzer W., Scheurer C., Wall B.F.,1992. Results of a Dosimetry Study in the European Community on Frequent X-ray Examinations in Infants. Radiat. Protect. Dosimetry 43, 31-36.

Perlmutter N., Arthur R., Beluffi G., Cook V., Horwitz A.E., Kramer P., Montagne J.P., Thomas P. Schneider K., 1998. The quality criteria for diagnostic radiographic images in paediatrics. Radiat. Protect. Dosimetry 80, 45-48.

20/480

We suggest adding the following references:

"…implementation of quality criteria (Schneider, et al., 1993; Schneide,r et al. 1995)"

Schneider K., Kohn M.M., Bakowski C., Stein E., Freidhof C., Horwitz A.E., Padovani R., Wall B., Panzer W., Fendel H., 1993. Impact of radiographic imaging criteria on dose and image quality in infants in an EC-wide survey. Radiat. Protect. Dosim. 49, 73-76.

Schneider K., 1995. Evolution of Quality Assurance in Paediatric Radiology. Radiat. Protect. Dosim. 57, 119-123.

22/525

The publication by Kohn and the European Guidelines are identical, therefore Kohn should be deleted.

24/581-584

We propose adding the following to the text:

 "Videos, written materials or details of the procedure available for the viewing by the children […] which are specifically designed for children and parents viewing can also […]"

24/597-600

We propose deleting the following text to avoid confusion, and adding the following to the text:

"The size of the field of interest is more dependent on the underlying disease.  infants and younger children compared to adults due to more marked deformation of the normal anatomy with disease. Thus basic knowledge of paediatric anatomy and age specific disorders is also required from the radiographers to ensure proper beam limitation in all age groups."

25/627

The following sentences should be added after "[...] friendly and durable.": "The lead equivalent of lead-free protective clothing, however, depends on the radiation quality, i.e., tube voltage and filtration. Therefore, stating a single value for x-ray-protective clothing does not reveal the protective efficacy for the complete range of radiation quality. The energy dependent attenuation, which is measured in a broad beam geometry accounting for scattered radiation, characterises the radiation protection much more precisely (Eder, et al. 2005)."

Eder H., Panzer W., Schöfer H., 2005. Ist der Bleigleichwert zur Beurteilung der Schutzwirkung bleifreier Röntgenschutzkleidung geeignet? RöFo 177, 399-404.

26/643

We propose changing or adding the following sentences: „If feasible and if the examination as well as the diagnosis is not affected, the eyes should be shielded with […] volume. Lead-equivalent eyeglasses  should be used with caution, however, as the radiation protection rating of lead-equivalent eye-glasses is not internationally standardised, so far.“ 

26/668-669

„Knowledge […] of appropriate radiographic exposure factors, i.e. …“: The tube current-exposure time product (tube voltage, mAs-product) is missing in the list following the quote above.

27/671

„total“à „inherent“. Additional filters may actually be used to modify total filtration.

27/678

IEC standards (e.g. IEC 62220-1) indicate a maximum focal spot value of 1.2. Therefore, the following should be added:

„…(IEC62220-1 requires a focal spot value of 1.2)”

27/691

We suggest the following addition:

„Additional filters […] with except of neonates or very small infants.“

27/695

Include reference:

„…higher patient doses (Fendel, et al. 1989)“

Fendel H., Schneider K., Kohn M.M., Bakowski C., 1989. Optimization of Image Quality and Patient Dose - Paediatric Radiology. In: Optimization of Image Quality and Patient Exposure in Diagnostic Radiology. Editors: Moores B.M., Wall B.F., Eriskat H. & Schibilla H. Brit. Institute of Radiology. BIR Report 20, 91-101

28/714

We propose deleting the following text:

“When anti-scatter measures are necessary, grid ratios of eight and line numbers of 40/cm (moving grid) are usually sufficient even at higher radiographic voltage.”

28/716-718

The following sentence presents a problem: "However, in newer …..increase in dose." Paediatric radiologists (in Europe) believe that no grid is necessary for fluoroscopy for children under 8, if collimated precisely. In our publication (Schneider et al. 2000) it is clearly demonstrated that the use of grids on babies greatly increases the dose without improving the quality of images at all. Furthermore, this is the only study which has been carried out in 12 European childrens hospitals, led by a paediatric radiologist, and in which fluoroscopy examination parameters (kV, filtration, grid), dose and image quality could be evaluated.

Schneider K., Perlmutter N., Arthur R., Cook V., Horwitz A.E., Thomas P. Kramer P., Montagne J.P., Ernst G., Kohn M.M., Panzer W., Wall B.,2000. Micturition cysturethrography in paediatric patients in selected children´s hospitals in Europe: evaluation of fluoroscopy technique, image quality and dose. Radiat Prot Dosim 90, 197-201.

28/731

„should patients“ à „patients should“

30/776

47/1297

48/1322

These statements refer to the patients size, not age:

"patient age" à "patient size"

"patient weight or age" à " weight or patient size"

"depending on age of patient" à " depending on size of patient "

30/771

1 mGy is too high, therefore change to: 

"fraction of 1 mGy" à "range of 1 to 10 µGy"

30/783-785

Here a reference to the need of paediatric curves should be included:

"Special paediatric characteristic operational curves should be available in the fluoroscopic equipment."

30/795

"...such as 12 pulse and ..." should be deleted as these generators are no longer the state of the art.

31/801

Add reference to the publication by Fendel, et al. at the end of the sentence.

"… or more (Fendel, et al., 1998)."

Fendel H., Schneider K., Kohn M.M., Bakowski C., 1989. Optimization of Image Quality and Patient Dose - Paediatric Radiology. In: Optimization of Image Quality and Patient Exposure in Diagnostic Radiology. Editors: Moores B.M., Wall B.F., Eriskat H. & Schibilla H. Brit. Institute of Radiology. BIR Report 20, 91-101.

31/815

"because"à "due to"

31/821

The distance should be specified:

"A recommended minimal distance should be 1.5 meters."

33/870

This sentence should be updated:

"…like detail of the peripheral skeleton, speed classes of 200 – 400 can be used, for all other purposes, speed classes of 400 – 800 must be preferred."

33/889

The following should be added to the sentence on pulsed units:

""… by  using  reduction  in  the  number  of  exposures  per  second.  Today, generator pulsed and grid-controlled fluoroscopy systems are available. Grid-controlled units use a negatively charged grid interposed between the cathode and the anode of the X-ray tube."

34/896

The following should be deleted:

„grid controlled“

34/898

The following should be added to the quotation of references:

Schneider K., Perlmutter N., Arthur R., Cook V., Horwitz A.E., Thomas P. Kramer P., Montagne J.P., Ernst G., Kohn M.M., Panzer W., Wall B.,2000. Micturition cysturethrography in paediatric patients in selected children´s hospitals in Europe: evaluation of fluoroscopy technique, image quality and dose. Radiat Prot Dosim 90, 197-201.

34/907

The second part of the sentence should be deleted as it is not coherent with the rest: „The image intensifier should be as close to the patient as possible (to maximize […] on the one hand and to improve image quality through improvement of resolution).“ 

35/932

The measurement of air kerma should be deleted as it is not implemented and therefore cannot be required and the DAP should be added: 

“KA,R (total air kerma at the reference point) or PKA (air kerma x X-ray beam area, also known as dose area product = DAP) for the procedure should be recorded and compared with benchmark figures …”

37/1002

The following should be added to this sentence:

A unique feature in paediatric fluoroscopic diagnostic and intervention is the large size of the image intensifiers relative to the infant size.”

44/1176

The following should be changed for ethical reasons:

"poor prognosis" à"higher risk of disease related mortality"

46/1252

"a factor or two" à "a factor of two"

47/1287

The word "differences" can be deleted.

48/1314

It should be added that this refers to the diameter of the phantom:

"28 cm diameter".

49/Tabelle

The table is confusing, units are missing, some of the values are too high; DLP is missing for some measurements, which is why a revised table should used. Dr. Frush should be contacted to this end.

50/1358

"8-64 detector rows" à "4 detector rows or more"

51/1409

"4-6 mm" à "3-5 mm"

52/1421

"left to right" à "lateral" (analogous to a.p.)

52/1435

"a number" à "A few"

58/1617-1621

We suggest the following new phrasing:

"In cases of abnormal head appearance e.g. hydrocephalus with open fontanel, ultrasound is indicated. In cases of craniosynostosis or other severe malformations of the head and neck 3-D reconstruction prior to cranial surgery which necessitates a CT examination. For possible shunt malfunction in operated hydrocephalus, radiography of the whole valve system is indicated."

58/1626

"CT" à "Low dose CT"

59/1631

"…while MRI radiography or CT are indicated only…"

59/1634

"Ultrasound or MRI is indicated"