Radiation Protection Dosimetry Advance Access published April 5, 2015 Radiation Protection Dosimetry (2015), pp. 1–4
doi:10.1093/rpd/ncv121
COLLECTIVE EFFECTIVE DOSE FROM DIAGNOSTIC RADIOLOGY IN UKRAINE L. Stadnyk*, O. Shalopa and O. Nosyk Central Laboratory of Radiation Hygiene of Medical Staff and Patients, Grigoriev Institute for Medical Radiology, Kharkov, Ukraine *Corresponding author: [email protected]
INTRODUCTION Medical exposure in diagnostic radiology is the main man-made source of radiation. During the past decades, both individual patient doses and frequency of examinations have significantly increased worldwide(1). For comparison between different sources of exposure in terms of additional radiation cancer risk, the concept of collective effective dose (CED) is used(1). More than 40 million X-ray diagnostic examinations are carried out annually in Ukraine for a population of about 46 million. Diagnostic radiology is the largest man-made radiation source, contributing to up to 80 % of the CED of the Ukrainian population from man-made sources. Till now, the typical effective doses from different types of X-ray diagnostic examinations were estimated using tabulated data, provided in the Order of Ministry of Health ~ 295 from 18 July 2001(2). These estimates were taken from the literature and did not reflect the current practice in the X-ray departments in the country. According to the recommendations published by the European Commission (EC), the assessment of CEDs should be based on effective doses calculated from the results of measurements performed in the X-ray facilities in the country(3). Patient dose measurements, together with the introduction of quality control programme, should be used as a tool for optimisation, as recommended by the International Commission on Radiological Protection (ICRP)(4).
The purpose of this study was to estimate the annual CED of Ukrainian population from the most common X-ray diagnostic procedures and to assess the additional cancer risk due to medical diagnostic exposure. MATERIALS AND METHODS The frequencies and effective doses for the most common X-ray diagnostic examinations in Ukraine were assessed in the frame of the EC Study on European Population Doses from Medical Exposure (Dose Datamed 2—DDM2, http://ddmed.eu/). According to the EC Guidance RP154, the ‘TOP 20 exams’ include 20 types of X-ray diagnostic examinations or procedures that give the highest contribution to the total CED(3). Data about the frequency of X-ray diagnostic examinations or procedures in all regions of Ukraine were collected in 2009–2012 by means of questionnaire prepared by the Grigoriev Institute for Medical Radiology (GIMR). For regions not responding to the GIMR survey, the information of the Medical Statistic Centre of the Ministry of Health has been used. The questionnaire on structure of X-ray procedures in medical institutions (hospitals) was intended to study the distribution of the following X-ray examinations: fluorography, radiography, fluoroscopy, mammography, dental radiography, computed tomography (CT), angiography and interventional radiology procedures.
# The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected]
Downloaded from http://rpd.oxfordjournals.org/ at Simon Fraser University on June 6, 2015
The frequencies and effective doses for the most common X-ray diagnostic examinations in Ukraine were assessed in the frame of the European Commission (EC) Study on European Population Doses from Medical Exposure (Dose Datamed 2). The average effective doses for all radiographic procedures were estimated using the ODS-60 software (Finland). The estimation of the effective doses for the chest film fluorography was carried out from the results of own representative measurements with thermoluminescent (TL) dosimetry and a standard Alderson-Rando phantom. The effective doses for fluoroscopy procedures were assessed using the Russian guidelines for estimation of effective doses. For all other X-ray examinations and procedures [computed tomography (CT), angiography and interventional procedures], typical effective dose values were taken from the EC Guidance RP154. The most frequently performed in Ukraine is chest film fluorography, with 389 examinations per 1000 population annually, reflecting in the greatest contribution to the total collective effective dose (CED) of 428 mSv per 1000 population (44 %). The total frequency and CED from all X-ray diagnostic examinations and procedures were estimated to be 1218 examinations and 1060 mSv per 1000 populations, respectively. The expected additional cancer risk from X-ray diagnostic examinations and interventional procedures is 2680 cases per year, with 1200 of them due to the contribution of chest fluorography. The main important action in radiation protection of patients in diagnostic radiology is the organisation of the monitoring of patient doses for different types of X-ray diagnostic examinations and replacement of chest film fluorography with digital X-ray systems.
L. STADNYK ET AL.
The assessment of cancer radiation risks from X-ray diagnostic exposure was performed applying the ICRP cancer risk coefficient (6): R ¼ Eeff k; where Eeff is the annual CED, man-mSv, and k ¼ 5.5` 1022 Sv21 is the cancer risk coefficient.
RESULTS Table 1 presents data for the annual frequency of the most common X-ray examinations, the average effective dose per procedure, the CEDs per 1000 population and the total annual CEDs. Twenty-two X-ray procedures were selected for this analysis, including the ‘TOP 20 exams’ from the EC project DDM2, plus chest fluorography (separately for film and digital imaging). The chest fluorography was added as this examination performed for mass tuberculosis screening in Ukraine is the most frequently performed type of X-ray examinations, whereas it is not performed at a routine basis in other European countries participating in the DDM2 survey. The chest fluorography
Table 1. CEDs for most common X-ray procedures in Ukraine. X-ray procedures
Film fluorography (screening) Digital radiography of chest (screening) Chest/thorax Cervical spine Thoracic spine Lumbar spine Mammography Abdomen Pelvis and hip Barium meal (Ba meal) Barium enema (Ba enema) Barium follow-through (Ba follow-through) Intravenous urography (IVU) CT head CT neck CT chest CT spine CT abdomen CT pelvis CT trunk Coronary dilatation/stenting (PTCA) Angiography Total
Total number per year (thousand)
Annual frequency per 1000 pop
Average effective dose per examination (mSv)
Annual CED per 1000 pop (mSv)
Annual CED (manmSv)
17 857.0 5036.0
389.05 109.73
1.1 0.2
428.0 21.9
19 643.0 1007.0
6517.0 1188.0 905.0 2269.0 591.0 1344.0 1080.0 335.0 108.0 49.4
141.99 25.90 19.72 49.45 12.89 29.29 23.55 7.31 2.37 1.08
0.1 0.7 2.0 2.5 0.4 1.8 1.6 12.0 12.5 26.0
14.2 18.1 39.4 123.6 5.2 52.7 37.7 87.8 29.6 26.4
652.0 832.2 1810.4 5674.3 236.7 2420.3 1729.3 4029.0 1358.0 1284.0
99.4 154.0 5.1 60.9 25.7 65.9 12.8 2.5 5.4
2.17 0.81 3.36 0.11 1.33 0.56 1.44 0.28 0.06
3.5 2.4 2.8 8.2 6.0 13.5 8.8 24.4 15.4
7.6 8.1 0.3 10.9 3.4 19.4 2.5 1.4 1.8
348.0 370.2 14.4 500.0 154.2 890.0 113.1 62.7 82.6
37.1 32 718.0
0.12 1000.0
8.6 —
6.9 947.0
319.0 43 530.0
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Downloaded from http://rpd.oxfordjournals.org/ at Simon Fraser University on June 6, 2015
More than 40 types of diagnostic procedures were included in this questionnaire. Twenty-four regions of Ukraine (90 %) responded to the survey. The average effective doses for radiographic procedures were estimated using the ODS-60 software (Rados Technology, Finland). Effective dose for chest film fluorography was estimated from the results of own representative measurements with thermoluminescent (TL) dosimetry and a standard Alderson-Rando phantom. This phantom has 39 layers with holes for location of 255 TL detectors thus allowing to determine the absorbed doses in 17 organs and tissues. For estimation of effective dose, the tissue weighting factors from the ICRP Publication 60 were applied(4). Assessment of patient doses from fluoroscopy procedures has not been carried out in Ukraine. The effective doses were assessed using the Russian guidelines for dose estimation in diagnostic radiology, considering the equipment and fluoroscopy procedures in Ukraine are similar to those in Russia(5). For all other X-ray examinations and procedures (CT, angiography and interventional procedures), typical effective dose values were taken from the EC Guidance RP154(3).
COLLECTIVE EFFECTIVE DOSE FROM DIAGNOSTIC RADIOLOGY
Figure 3. Distribution of the CED for fluoroscopy examinations. Figure 2. Distribution of the CED for plain radiography.
has the highest contribution to the CED of 428 mSv per 1000 population (44 %). The highest individual effective doses, from 12 to 26 mSv, were found for contract fluoroscopy examinations and for CT, as well as for interventional procedures in the range of 9–15 mSv. Figure 1 shows the distribution of the CEDs for the main types of X-ray examinations. The largest contributions of 44 % has the film chest fluorography, followed by radiography of the lumbar spine of 12 % and the contract examinations of the abdomen, stomach, intestines and Barium enema of 15.0 %. Despite the high effective doses, the contribution of CT and interventional procedures to the total CED is still low: 4 % for CT and 1 % for interventional procedures, due to their relatively low frequency.
Figure 4. Distribution of the CED for CT examinations.
The distributions of the annual CEDs for the radiographic, fluoroscopic and CT examinations are presented in Figures 2–4. The largest contribution to the
Page 3 of 4
Downloaded from http://rpd.oxfordjournals.org/ at Simon Fraser University on June 6, 2015
Figure 1. Contribution of different X-ray examinations to the total CED.
L. STADNYK ET AL. Table 2. Correction factors to estimate overall total frequencies and CEDs from the results evaluated by ‘TOP 20 exams’ approach. Parameter
Correction factors, overall total/‘TOP 20’ total Plain radiography
Fluoroscopy
CT
Interventional radiology
2.25 1.12
2.04 1.40
1.13 1.23
3.23 2.97
Frequency CED
Table 3. Overall frequency and CED per 1000 population for the main groups of X-ray procedures. Plain radiography
Fluoroscopy
CT
Interventional radiology
Total (per 1000 pop)
1181.2 777.2
28.1 221.5
8.0 56.3
0.4 5.3
1218.0 1060.4
Frequency CED (mSv)
CED from plain radiography comes from the examinations of lumbar spine (43 %), from the Barium meal (56 %) for fluoroscopy procedures and from CT of abdomen (42 %). The total frequency and CED from all types of X-ray diagnostic examinations and procedures were assessed by applying the correction factors (Table 2) established from the EC project Dose Datamed 2. The total frequency of X-ray diagnostic examinations and procedures was estimated to be 1218 examinations per 1000 population (Table 3). The total CED for all X-ray diagnostic examinations and procedures was 1060 mSv per 1000 population (1.06 mSv per capita). The total CED from conventional X-ray procedures (plain radiography and fluoroscopy) was 998.7 mSv per 1000 population, whereas CED from CT and interventional procedures together was 61.6 mSv. The expected additional cancer risk from medical X-ray diagnostic examinations and interventional procedures is 2680 cases per year, with 1200 of them due to the contribution of chest fluorography. CONCLUSIONS The total frequency of all X-ray procedures per 1000 Ukrainian population was estimated to 1218 examinations per year, and the corresponding total CED per capita was 1.06 mSv. The most frequently performed examination in Ukraine is chest film fluorography, with 389 examinations per 1000 population annually, reflecting in the highest contribution to the total CED of 428 mSv per 1000 population (44 %).
The expected additional cancer risk from X-ray diagnostic examinations and interventional procedures is 2680 cases per year, with 1200 of them due to the contribution of chest fluorography. The results of this study call for urgent actions needed to implement regular monitoring of patient doses in diagnostic radiology and replacement of old chest film-based fluorography systems with digital equipment. Actions are needed to justify the future need of mass chest screening in Ukraine.
REFERENCES 1. UNSCEAR. Sources and Effects of Ionizing Radiation. United Nations scientific committee on the effects of atomic radiation report to the general assembly with scientific annexes. Vol. I– II: Effects (2000). 2. Order of Health Ministry ~ 295 from 7/18/2001 on the establishment of monitoring and recording of individual doses to the population in radiological procedures. [Electronic recourse.] Mode of access: http://www.uazakov.com/big/ text1093/pg1. 3. European Commission. Radiation Protection 154: European Guidance on Estimating Population Doses from Medical X-Ray Procedures (2008). 4. ICRP. Recommendations of the International Commission on Radiological Protection. ICRP Publication 60. Ann. ICRP 21 (1– 3) (1991). 5. Federal Centre for Sanitary Inspection of Russia Health Ministry. Control of Patient Effective Dose in Medical X-Ray Examinations: Methodical Guidelines (2004). 6. ICRP. Recommendations of the International Commission on Radiological Protection. ICRP Publication 103. Ann. ICRP 37 (2–4) (2008).
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Parameter
doi:10.1093/rpd/ncv121
COLLECTIVE EFFECTIVE DOSE FROM DIAGNOSTIC RADIOLOGY IN UKRAINE L. Stadnyk*, O. Shalopa and O. Nosyk Central Laboratory of Radiation Hygiene of Medical Staff and Patients, Grigoriev Institute for Medical Radiology, Kharkov, Ukraine *Corresponding author: [email protected]
INTRODUCTION Medical exposure in diagnostic radiology is the main man-made source of radiation. During the past decades, both individual patient doses and frequency of examinations have significantly increased worldwide(1). For comparison between different sources of exposure in terms of additional radiation cancer risk, the concept of collective effective dose (CED) is used(1). More than 40 million X-ray diagnostic examinations are carried out annually in Ukraine for a population of about 46 million. Diagnostic radiology is the largest man-made radiation source, contributing to up to 80 % of the CED of the Ukrainian population from man-made sources. Till now, the typical effective doses from different types of X-ray diagnostic examinations were estimated using tabulated data, provided in the Order of Ministry of Health ~ 295 from 18 July 2001(2). These estimates were taken from the literature and did not reflect the current practice in the X-ray departments in the country. According to the recommendations published by the European Commission (EC), the assessment of CEDs should be based on effective doses calculated from the results of measurements performed in the X-ray facilities in the country(3). Patient dose measurements, together with the introduction of quality control programme, should be used as a tool for optimisation, as recommended by the International Commission on Radiological Protection (ICRP)(4).
The purpose of this study was to estimate the annual CED of Ukrainian population from the most common X-ray diagnostic procedures and to assess the additional cancer risk due to medical diagnostic exposure. MATERIALS AND METHODS The frequencies and effective doses for the most common X-ray diagnostic examinations in Ukraine were assessed in the frame of the EC Study on European Population Doses from Medical Exposure (Dose Datamed 2—DDM2, http://ddmed.eu/). According to the EC Guidance RP154, the ‘TOP 20 exams’ include 20 types of X-ray diagnostic examinations or procedures that give the highest contribution to the total CED(3). Data about the frequency of X-ray diagnostic examinations or procedures in all regions of Ukraine were collected in 2009–2012 by means of questionnaire prepared by the Grigoriev Institute for Medical Radiology (GIMR). For regions not responding to the GIMR survey, the information of the Medical Statistic Centre of the Ministry of Health has been used. The questionnaire on structure of X-ray procedures in medical institutions (hospitals) was intended to study the distribution of the following X-ray examinations: fluorography, radiography, fluoroscopy, mammography, dental radiography, computed tomography (CT), angiography and interventional radiology procedures.
# The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected]
Downloaded from http://rpd.oxfordjournals.org/ at Simon Fraser University on June 6, 2015
The frequencies and effective doses for the most common X-ray diagnostic examinations in Ukraine were assessed in the frame of the European Commission (EC) Study on European Population Doses from Medical Exposure (Dose Datamed 2). The average effective doses for all radiographic procedures were estimated using the ODS-60 software (Finland). The estimation of the effective doses for the chest film fluorography was carried out from the results of own representative measurements with thermoluminescent (TL) dosimetry and a standard Alderson-Rando phantom. The effective doses for fluoroscopy procedures were assessed using the Russian guidelines for estimation of effective doses. For all other X-ray examinations and procedures [computed tomography (CT), angiography and interventional procedures], typical effective dose values were taken from the EC Guidance RP154. The most frequently performed in Ukraine is chest film fluorography, with 389 examinations per 1000 population annually, reflecting in the greatest contribution to the total collective effective dose (CED) of 428 mSv per 1000 population (44 %). The total frequency and CED from all X-ray diagnostic examinations and procedures were estimated to be 1218 examinations and 1060 mSv per 1000 populations, respectively. The expected additional cancer risk from X-ray diagnostic examinations and interventional procedures is 2680 cases per year, with 1200 of them due to the contribution of chest fluorography. The main important action in radiation protection of patients in diagnostic radiology is the organisation of the monitoring of patient doses for different types of X-ray diagnostic examinations and replacement of chest film fluorography with digital X-ray systems.
L. STADNYK ET AL.
The assessment of cancer radiation risks from X-ray diagnostic exposure was performed applying the ICRP cancer risk coefficient (6): R ¼ Eeff k; where Eeff is the annual CED, man-mSv, and k ¼ 5.5` 1022 Sv21 is the cancer risk coefficient.
RESULTS Table 1 presents data for the annual frequency of the most common X-ray examinations, the average effective dose per procedure, the CEDs per 1000 population and the total annual CEDs. Twenty-two X-ray procedures were selected for this analysis, including the ‘TOP 20 exams’ from the EC project DDM2, plus chest fluorography (separately for film and digital imaging). The chest fluorography was added as this examination performed for mass tuberculosis screening in Ukraine is the most frequently performed type of X-ray examinations, whereas it is not performed at a routine basis in other European countries participating in the DDM2 survey. The chest fluorography
Table 1. CEDs for most common X-ray procedures in Ukraine. X-ray procedures
Film fluorography (screening) Digital radiography of chest (screening) Chest/thorax Cervical spine Thoracic spine Lumbar spine Mammography Abdomen Pelvis and hip Barium meal (Ba meal) Barium enema (Ba enema) Barium follow-through (Ba follow-through) Intravenous urography (IVU) CT head CT neck CT chest CT spine CT abdomen CT pelvis CT trunk Coronary dilatation/stenting (PTCA) Angiography Total
Total number per year (thousand)
Annual frequency per 1000 pop
Average effective dose per examination (mSv)
Annual CED per 1000 pop (mSv)
Annual CED (manmSv)
17 857.0 5036.0
389.05 109.73
1.1 0.2
428.0 21.9
19 643.0 1007.0
6517.0 1188.0 905.0 2269.0 591.0 1344.0 1080.0 335.0 108.0 49.4
141.99 25.90 19.72 49.45 12.89 29.29 23.55 7.31 2.37 1.08
0.1 0.7 2.0 2.5 0.4 1.8 1.6 12.0 12.5 26.0
14.2 18.1 39.4 123.6 5.2 52.7 37.7 87.8 29.6 26.4
652.0 832.2 1810.4 5674.3 236.7 2420.3 1729.3 4029.0 1358.0 1284.0
99.4 154.0 5.1 60.9 25.7 65.9 12.8 2.5 5.4
2.17 0.81 3.36 0.11 1.33 0.56 1.44 0.28 0.06
3.5 2.4 2.8 8.2 6.0 13.5 8.8 24.4 15.4
7.6 8.1 0.3 10.9 3.4 19.4 2.5 1.4 1.8
348.0 370.2 14.4 500.0 154.2 890.0 113.1 62.7 82.6
37.1 32 718.0
0.12 1000.0
8.6 —
6.9 947.0
319.0 43 530.0
Page 2 of 4
Downloaded from http://rpd.oxfordjournals.org/ at Simon Fraser University on June 6, 2015
More than 40 types of diagnostic procedures were included in this questionnaire. Twenty-four regions of Ukraine (90 %) responded to the survey. The average effective doses for radiographic procedures were estimated using the ODS-60 software (Rados Technology, Finland). Effective dose for chest film fluorography was estimated from the results of own representative measurements with thermoluminescent (TL) dosimetry and a standard Alderson-Rando phantom. This phantom has 39 layers with holes for location of 255 TL detectors thus allowing to determine the absorbed doses in 17 organs and tissues. For estimation of effective dose, the tissue weighting factors from the ICRP Publication 60 were applied(4). Assessment of patient doses from fluoroscopy procedures has not been carried out in Ukraine. The effective doses were assessed using the Russian guidelines for dose estimation in diagnostic radiology, considering the equipment and fluoroscopy procedures in Ukraine are similar to those in Russia(5). For all other X-ray examinations and procedures (CT, angiography and interventional procedures), typical effective dose values were taken from the EC Guidance RP154(3).
COLLECTIVE EFFECTIVE DOSE FROM DIAGNOSTIC RADIOLOGY
Figure 3. Distribution of the CED for fluoroscopy examinations. Figure 2. Distribution of the CED for plain radiography.
has the highest contribution to the CED of 428 mSv per 1000 population (44 %). The highest individual effective doses, from 12 to 26 mSv, were found for contract fluoroscopy examinations and for CT, as well as for interventional procedures in the range of 9–15 mSv. Figure 1 shows the distribution of the CEDs for the main types of X-ray examinations. The largest contributions of 44 % has the film chest fluorography, followed by radiography of the lumbar spine of 12 % and the contract examinations of the abdomen, stomach, intestines and Barium enema of 15.0 %. Despite the high effective doses, the contribution of CT and interventional procedures to the total CED is still low: 4 % for CT and 1 % for interventional procedures, due to their relatively low frequency.
Figure 4. Distribution of the CED for CT examinations.
The distributions of the annual CEDs for the radiographic, fluoroscopic and CT examinations are presented in Figures 2–4. The largest contribution to the
Page 3 of 4
Downloaded from http://rpd.oxfordjournals.org/ at Simon Fraser University on June 6, 2015
Figure 1. Contribution of different X-ray examinations to the total CED.
L. STADNYK ET AL. Table 2. Correction factors to estimate overall total frequencies and CEDs from the results evaluated by ‘TOP 20 exams’ approach. Parameter
Correction factors, overall total/‘TOP 20’ total Plain radiography
Fluoroscopy
CT
Interventional radiology
2.25 1.12
2.04 1.40
1.13 1.23
3.23 2.97
Frequency CED
Table 3. Overall frequency and CED per 1000 population for the main groups of X-ray procedures. Plain radiography
Fluoroscopy
CT
Interventional radiology
Total (per 1000 pop)
1181.2 777.2
28.1 221.5
8.0 56.3
0.4 5.3
1218.0 1060.4
Frequency CED (mSv)
CED from plain radiography comes from the examinations of lumbar spine (43 %), from the Barium meal (56 %) for fluoroscopy procedures and from CT of abdomen (42 %). The total frequency and CED from all types of X-ray diagnostic examinations and procedures were assessed by applying the correction factors (Table 2) established from the EC project Dose Datamed 2. The total frequency of X-ray diagnostic examinations and procedures was estimated to be 1218 examinations per 1000 population (Table 3). The total CED for all X-ray diagnostic examinations and procedures was 1060 mSv per 1000 population (1.06 mSv per capita). The total CED from conventional X-ray procedures (plain radiography and fluoroscopy) was 998.7 mSv per 1000 population, whereas CED from CT and interventional procedures together was 61.6 mSv. The expected additional cancer risk from medical X-ray diagnostic examinations and interventional procedures is 2680 cases per year, with 1200 of them due to the contribution of chest fluorography. CONCLUSIONS The total frequency of all X-ray procedures per 1000 Ukrainian population was estimated to 1218 examinations per year, and the corresponding total CED per capita was 1.06 mSv. The most frequently performed examination in Ukraine is chest film fluorography, with 389 examinations per 1000 population annually, reflecting in the highest contribution to the total CED of 428 mSv per 1000 population (44 %).
The expected additional cancer risk from X-ray diagnostic examinations and interventional procedures is 2680 cases per year, with 1200 of them due to the contribution of chest fluorography. The results of this study call for urgent actions needed to implement regular monitoring of patient doses in diagnostic radiology and replacement of old chest film-based fluorography systems with digital equipment. Actions are needed to justify the future need of mass chest screening in Ukraine.
REFERENCES 1. UNSCEAR. Sources and Effects of Ionizing Radiation. United Nations scientific committee on the effects of atomic radiation report to the general assembly with scientific annexes. Vol. I– II: Effects (2000). 2. Order of Health Ministry ~ 295 from 7/18/2001 on the establishment of monitoring and recording of individual doses to the population in radiological procedures. [Electronic recourse.] Mode of access: http://www.uazakov.com/big/ text1093/pg1. 3. European Commission. Radiation Protection 154: European Guidance on Estimating Population Doses from Medical X-Ray Procedures (2008). 4. ICRP. Recommendations of the International Commission on Radiological Protection. ICRP Publication 60. Ann. ICRP 21 (1– 3) (1991). 5. Federal Centre for Sanitary Inspection of Russia Health Ministry. Control of Patient Effective Dose in Medical X-Ray Examinations: Methodical Guidelines (2004). 6. ICRP. Recommendations of the International Commission on Radiological Protection. ICRP Publication 103. Ann. ICRP 37 (2–4) (2008).
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Parameter
