Radiation Protection Dosimetry Advance Access published April 5, 2015 Radiation Protection Dosimetry (2015), pp. 1–4
doi:10.1093/rpd/ncv105
ROMANIAN MEDICAL EXPOSURE TO IONISING RADIATION IN 2012 O. Girjoaba* and A. Cucu National Institute of Public Health, 1-3 Dr. A. Leonte Street, Bucharest 050463, Romania *Corresponding author: [email protected]
INTRODUCTION Medical exposure, the main source of artificial exposure, shows an increasing trend in the last years, manifested both by increasing the number of examinations with ionising radiation and by increasing the patient dose level. National legal framework harmonised with the community provisions stipulates the obligation and responsibility of the public health network to ensure the radiological protection of the patient during the medical exposures to ionising radiation. In this respect, Ministry of Health (MoH) promoted Order no. 1542/2006(1) and Order no. 1003/2008,(2) which ensured a system concerning the registration, centralisation and reporting of patient doses on medical exposures to ionising radiation, at the national level, involving in this process all the diagnostic radiology and nuclear medicine departments. Annual results obtained for medical exposure to ionising radiation based on the data collected from Romanian hospitals are useful for the update of the national database and optimisation of diagnostic procedures. Medical exposure level is expressed in terms of annual collective dose and is estimated from annual frequencies and the mean effective dose per procedure for different types of radiological and nuclear medicine procedures. METHOD According to the legally binding provisions, the recording system at the hospital level shall include at
least patient data (name, personal identification number, gender, height and weight) and the information relevant for dose assessment (examination type, projection, procedure code, focus –film distance, field size, kV, mAs, values of dose–area product (DAP) or dose length product (DLP) for CT examinations and activity in MBq for nuclear medicine). The centralised data, at the hospital level, are reported quarterly to Radiation Hygiene Laboratory of the Public Health Departments, depending on the territorial assignation. The reporting forms of the centralised data have to contain the exam type, procedure code, total number per exam type and its distributions on age groups and gender groups. Dose information should be also available, in terms of DAP-meter values, ESD (entrance surface dose) or DLP indication for CT examinations and activity (MBq) for nuclear medicine procedures. MoH, through the National Institute of Public Health—Bucharest Regional Centre for Public Health, centralises the data of medical exposure to ionising radiation reported by Radiation Hygiene Laboratories of the local Public Health Departments from counties and Bucharest and elaborates an annual report. The actual study is based on the data received by the National Institute of Public Health—Regional Centre for Public Health, concerning the conventional radiology and CT procedures, but also nuclear medicine procedures performed during the year 2012. Conversion coefficients used for relating measured values of DAP/DLP indications to effective doses are estimated by the NRPB R262(3), and for nuclear medicine procedures, the conversion coefficients used
# The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected]
Downloaded from http://rpd.oxfordjournals.org/ at University of Sheffield on September 11, 2015
Medical exposure, the main source of artificial exposure, shows an increasing trend in the last years, manifested both by increasing the number of examinations with ionising radiation and by increasing the patient dose level. Annual results obtained for medical exposure to ionising radiation based on the data collected from Romanian hospitals are useful for the update of the national database and optimisation of diagnostic procedures in radiology and nuclear medicine. Medical exposure level is expressed in terms of annual collective dose and is evaluated from annual frequencies and the average effective dose per procedure for different types of radiological and nuclear medicine procedures. The Romanian hospitals reported during 2012 a number of 5 505 792 radiological examinations and 17 088 diagnostic procedures of nuclear medicine. Based on the data reported, the average effective doses and their contributions to the collective dose were evaluated. The main contributions to the collective dose of the radiological procedures are registered for CT abdomen and pelvis region, followed by thorax CT and head CT examinations. The next positions are fluoroscopic examination of the thorax and gastrointestinal disease and radiographic examination of the lumbar spine and thorax, which in spite of their low effective dose have an important contribution to the collective dose due to the large number of examinations. For nuclear medicine procedures, major contributions to collective dose are given by bone scintigraphy, followed by PET-CT and thyroid scintigraphy.
O. GIRJOABA AND A. CUCU
are from ICRP Publication 80 ‘Radiation Dose to Patients from Radiopharmaceuticals’(4). The estimated number of one type examination (used for the estimation of the annual collective effective dose per 1000 population) at national level is as follows: c¼m
N M
Table 1. Mean effective dose for main conventional radiology procedures.
RESULTS
Examination type
The distribution of radiological examinations reported shows that conventional radiography represents 73.02 % of the total radiological examinations, dental radiography 11.25 %, fluoroscopic examinations 8.43 %, computed tomography 6.96 and angiographic examinations are ,0.5 % of all radiological examinations reported. A total number of 4 020 145 of radiographic examinations and 464 267 fluoroscopic examinations were reported; the mean effective doses and also their contribution to the collective dose were estimated. Analysis of the distribution of annual consumption by the type of radiological examination reveals that both thorax radiography (25.9 %) and radiography of limbs and joints (22.5 %) remain exposures to ionising radiation with the highest frequency. These are followed at distance by thorax fluoroscopy (7.8 %) and lumbar spine, pelvis, cervical spine and head radiographic examinations, with similar percentages (4.6–4.8 %). For computed tomography, the sample data correspond to the main seven categories of exposure (head, cervical spine, lumbar spine, thorax, abdomen, pelvis and extremities), and other CT procedures not encoded by the MoH order, comprising a total of 383 034 examinations reported. Regarding the contribution of each type of exposure, it is found that the head CT examinations were most common, accounting for 48 % of all CT examinations, followed at distance by the CT scan of the abdomen (18 %). Note that the frequency of CT examinations by age group is the
Head Thorax Abdomen Pelvis and hip Arms and legs Cervical spine Lumbar spine Thoracic spine Breast Thorax (fluoroscopy) Ba-meal (fluoroscopy) Ba-emena (fluoroscopy)
Mean effective dose (mSv) 0.058+0.016 0.126+0.034 (AP) 0.138+0.037 (LAT) 0.371+0.100 0.466+0.126 0.015+0.004 0.110+0.030 0.344+0.093 (AP) 0.447+0.121 (LAT) 0.254+0.069 (AP) 0.267+0.072 (LAT) 0.234+0.119 (CC) 0.250+0.128 (MLO) 0.558+0.151 2.156+1.100 1.576+0.804
Table 2. Mean effective dose for main computed tomography procedures. Examination type Head Thorax Abdomen Pelvis and hip Arms and legs Cervical spine Lumbar spine
Page 2 of 4
Mean effective dose (mSv) 3.1+1.6 11.0+5.6 22.9+11.7 19.4+9.9 8.7+4.4 3.9+2.0 9.7+5.0
Downloaded from http://rpd.oxfordjournals.org/ at University of Sheffield on September 11, 2015
where m is the total number of reported examinations for a number M of X-ray equipment and N is the number of X-ray equipment at the national level. The study was performed from the data reported by the 38 territorial Radiation Hygiene Laboratories from counties and Bucharest from a total number of 41, representing 59.4 % from the total number of X-ray and nuclear medicine equipments. The number of X-ray examinations reported in 2012 were 5 505 792 for all X-ray-based radiology and 17 088 for diagnostic nuclear medicine. Mean effective doses per exam type and their contributions to the collective dose were estimated on a sample of 56 % of those reported.
highest for adults over 40 y, regardless of location. For the age group 0–15 y, there is a relative higher frequency in CT examinations of the limbs and joints (8.6 %), head (4.3 %) and cervical spine (3.5 %). Regarding the distribution of CT examinations according to the sex of the patient reveals a balanced frequency, except abdomen and pelvis examinations where women hold 66.9 % of these exams. The mean effective doses per main conventional radiology and computed tomography procedures are presented in Tables 1 and 2. In 2012 were reported a total of 18 867 interventional radiology procedures. From examinations’ frequency analysis, it resulted that the largest share is angiography with almost 51 % of reported examinations, followed by coronary angioplasty (23.5 %), cerebral angiography (7 %), lower limb angiography (5.5 %) and abdominal angiography (4.8 %). From the reported data prevalent are exposures for age group of .40 y. It can be remarked for the 16- to 40-y age group, of all examinations for each type of angiographic procedure, a rate
ROMANIAN MEDICAL EXPOSURE Table 3. Mean effective dose for main interventional radiology procedures. Examination type
6.9+3.5 9.0+4.6 3.8+1.9 8.4+4.3 4.1+2.1 3.4+1.8 3.7+1.9 21.7+11.1 6.3+3.2 6.1+3.1 4.8+2.4
of almost 20 % for cerebral angiography and a rate of 18 % for pelvic angiography. The mean effective doses for interventional radiology procedures are presented in Table 3. A total of 619 479 dental radiological examinations were reported, which are classified as intraoral, panoramic and general examinations. It can be noticed a high frequency for intraoral dental radiographies, representing 75 % of reported examinations. In terms of distribution of dental radiological examinations of patients according to age, there is a slightly higher frequency for the age group of 16– 40 y compared with the age group of .40 y. Based on the data reported, collective effective doses were estimated for major radiological procedures, as well as their contributions to the total collective dose. From the analysis of contributions to the collective effective dose (Figure 1), the largest share is registered in the CT abdomen and pelvis region, followed by thorax CT and head CTexaminations. The following positions are fluoroscopic examinations of the thorax and gastrointestinal disease and also radiographic examination of the lumbar spine and thorax. For nuclear medicine, 17 088 diagnostic procedures were reported in 2012. Analysing the percentage distribution of frequencies, it can be observed that bone scintigraphy holds .50 % of all diagnostic procedures of nuclear medicine performed, followed by thyroid scintigraphy, PET-CT, renal scintigraphy and scintigraphy of thyroid function. From the point of view of the main contributions to nuclear medicine diagnostic procedures in collective effective dose (Figure 2), bone scintigraphy is the first, followed by PET-CT and thyroid scintigraphy. The annual collective effective dose per 1000 population for all X-ray-based radiology without dental radiology is 370 mSv per 1000 capita (371 mSv per 1000 capita with dental radiology) and 373.5 mSv per 1000 capita for all diagnostic procedures (including radiology and nuclear medicine).
Figure
1. Contributions to collective effective dose estimated for the main radiological procedures.
Figure 2. Contributions to collective effective dose estimated for the main nuclear medicine procedures.
CONCLUSIONS The main contributions to the collective dose of the radiological procedures are registered for CT abdomen and pelvis region, followed by thorax and head CT examinations. The radiographic examinations of the lumbar spine and thorax have an important contribution to the collective dose due to the large number of examinations
Page 3 of 4
Downloaded from http://rpd.oxfordjournals.org/ at University of Sheffield on September 11, 2015
Cardiac angiography Cerebral angiography Carotid angiography Abdominal angiography Pelvic angiography Lower limb angiography Upper limb angiography PTCA Carotid angioplasty Peripheral angioplasty Renal angioplasty
Mean effective dose (mSv)
O. GIRJOABA AND A. CUCU
REFERENCES 1. Order of the Health Ministry no. 1542/2006 concerning the registration and reporting patient doses. Official Gazette from Romania. Part I no. 1042 (2006). 2. Order of the Health Ministry no. 1003/2008 for approving the use of registration forms and reporting data on medical exposures to ionizing radiation. Official Gazette from Romania. Part I no. 393 (2008). 3. Hart, D., Jones, D. G. and Wall, B. F. Estimation of effective dose in diagnostic radiology from entrance surface dose and dose area product measurements. NRPB-R262, National Radiological Protection Board (1994). 4. International Commission of Radiological Protection. Radiation dose to patients from radiopharmaceuticals. ICRP Publication 80, 28(3) (1998).
Page 4 of 4
Downloaded from http://rpd.oxfordjournals.org/ at University of Sheffield on September 11, 2015
although they have relatively low effective dose per procedure. The contribution of interventional radiology to collective effective dose is not very important due to the low examination frequency. A major contribution to collective effective dose estimated for nuclear medicine diagnostic procedures is given by bone scintigraphy and PET-CT. The data regarding the dose received by the patients are incompletely reported for some CTexaminations (for example, Abdomen&Pelvis or Trunk) because legislation does not mention these exam types. As a result, the contributions to collective effective dose might change. The specific regulations must be improved.
doi:10.1093/rpd/ncv105
ROMANIAN MEDICAL EXPOSURE TO IONISING RADIATION IN 2012 O. Girjoaba* and A. Cucu National Institute of Public Health, 1-3 Dr. A. Leonte Street, Bucharest 050463, Romania *Corresponding author: [email protected]
INTRODUCTION Medical exposure, the main source of artificial exposure, shows an increasing trend in the last years, manifested both by increasing the number of examinations with ionising radiation and by increasing the patient dose level. National legal framework harmonised with the community provisions stipulates the obligation and responsibility of the public health network to ensure the radiological protection of the patient during the medical exposures to ionising radiation. In this respect, Ministry of Health (MoH) promoted Order no. 1542/2006(1) and Order no. 1003/2008,(2) which ensured a system concerning the registration, centralisation and reporting of patient doses on medical exposures to ionising radiation, at the national level, involving in this process all the diagnostic radiology and nuclear medicine departments. Annual results obtained for medical exposure to ionising radiation based on the data collected from Romanian hospitals are useful for the update of the national database and optimisation of diagnostic procedures. Medical exposure level is expressed in terms of annual collective dose and is estimated from annual frequencies and the mean effective dose per procedure for different types of radiological and nuclear medicine procedures. METHOD According to the legally binding provisions, the recording system at the hospital level shall include at
least patient data (name, personal identification number, gender, height and weight) and the information relevant for dose assessment (examination type, projection, procedure code, focus –film distance, field size, kV, mAs, values of dose–area product (DAP) or dose length product (DLP) for CT examinations and activity in MBq for nuclear medicine). The centralised data, at the hospital level, are reported quarterly to Radiation Hygiene Laboratory of the Public Health Departments, depending on the territorial assignation. The reporting forms of the centralised data have to contain the exam type, procedure code, total number per exam type and its distributions on age groups and gender groups. Dose information should be also available, in terms of DAP-meter values, ESD (entrance surface dose) or DLP indication for CT examinations and activity (MBq) for nuclear medicine procedures. MoH, through the National Institute of Public Health—Bucharest Regional Centre for Public Health, centralises the data of medical exposure to ionising radiation reported by Radiation Hygiene Laboratories of the local Public Health Departments from counties and Bucharest and elaborates an annual report. The actual study is based on the data received by the National Institute of Public Health—Regional Centre for Public Health, concerning the conventional radiology and CT procedures, but also nuclear medicine procedures performed during the year 2012. Conversion coefficients used for relating measured values of DAP/DLP indications to effective doses are estimated by the NRPB R262(3), and for nuclear medicine procedures, the conversion coefficients used
# The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: [email protected]
Downloaded from http://rpd.oxfordjournals.org/ at University of Sheffield on September 11, 2015
Medical exposure, the main source of artificial exposure, shows an increasing trend in the last years, manifested both by increasing the number of examinations with ionising radiation and by increasing the patient dose level. Annual results obtained for medical exposure to ionising radiation based on the data collected from Romanian hospitals are useful for the update of the national database and optimisation of diagnostic procedures in radiology and nuclear medicine. Medical exposure level is expressed in terms of annual collective dose and is evaluated from annual frequencies and the average effective dose per procedure for different types of radiological and nuclear medicine procedures. The Romanian hospitals reported during 2012 a number of 5 505 792 radiological examinations and 17 088 diagnostic procedures of nuclear medicine. Based on the data reported, the average effective doses and their contributions to the collective dose were evaluated. The main contributions to the collective dose of the radiological procedures are registered for CT abdomen and pelvis region, followed by thorax CT and head CT examinations. The next positions are fluoroscopic examination of the thorax and gastrointestinal disease and radiographic examination of the lumbar spine and thorax, which in spite of their low effective dose have an important contribution to the collective dose due to the large number of examinations. For nuclear medicine procedures, major contributions to collective dose are given by bone scintigraphy, followed by PET-CT and thyroid scintigraphy.
O. GIRJOABA AND A. CUCU
are from ICRP Publication 80 ‘Radiation Dose to Patients from Radiopharmaceuticals’(4). The estimated number of one type examination (used for the estimation of the annual collective effective dose per 1000 population) at national level is as follows: c¼m
N M
Table 1. Mean effective dose for main conventional radiology procedures.
RESULTS
Examination type
The distribution of radiological examinations reported shows that conventional radiography represents 73.02 % of the total radiological examinations, dental radiography 11.25 %, fluoroscopic examinations 8.43 %, computed tomography 6.96 and angiographic examinations are ,0.5 % of all radiological examinations reported. A total number of 4 020 145 of radiographic examinations and 464 267 fluoroscopic examinations were reported; the mean effective doses and also their contribution to the collective dose were estimated. Analysis of the distribution of annual consumption by the type of radiological examination reveals that both thorax radiography (25.9 %) and radiography of limbs and joints (22.5 %) remain exposures to ionising radiation with the highest frequency. These are followed at distance by thorax fluoroscopy (7.8 %) and lumbar spine, pelvis, cervical spine and head radiographic examinations, with similar percentages (4.6–4.8 %). For computed tomography, the sample data correspond to the main seven categories of exposure (head, cervical spine, lumbar spine, thorax, abdomen, pelvis and extremities), and other CT procedures not encoded by the MoH order, comprising a total of 383 034 examinations reported. Regarding the contribution of each type of exposure, it is found that the head CT examinations were most common, accounting for 48 % of all CT examinations, followed at distance by the CT scan of the abdomen (18 %). Note that the frequency of CT examinations by age group is the
Head Thorax Abdomen Pelvis and hip Arms and legs Cervical spine Lumbar spine Thoracic spine Breast Thorax (fluoroscopy) Ba-meal (fluoroscopy) Ba-emena (fluoroscopy)
Mean effective dose (mSv) 0.058+0.016 0.126+0.034 (AP) 0.138+0.037 (LAT) 0.371+0.100 0.466+0.126 0.015+0.004 0.110+0.030 0.344+0.093 (AP) 0.447+0.121 (LAT) 0.254+0.069 (AP) 0.267+0.072 (LAT) 0.234+0.119 (CC) 0.250+0.128 (MLO) 0.558+0.151 2.156+1.100 1.576+0.804
Table 2. Mean effective dose for main computed tomography procedures. Examination type Head Thorax Abdomen Pelvis and hip Arms and legs Cervical spine Lumbar spine
Page 2 of 4
Mean effective dose (mSv) 3.1+1.6 11.0+5.6 22.9+11.7 19.4+9.9 8.7+4.4 3.9+2.0 9.7+5.0
Downloaded from http://rpd.oxfordjournals.org/ at University of Sheffield on September 11, 2015
where m is the total number of reported examinations for a number M of X-ray equipment and N is the number of X-ray equipment at the national level. The study was performed from the data reported by the 38 territorial Radiation Hygiene Laboratories from counties and Bucharest from a total number of 41, representing 59.4 % from the total number of X-ray and nuclear medicine equipments. The number of X-ray examinations reported in 2012 were 5 505 792 for all X-ray-based radiology and 17 088 for diagnostic nuclear medicine. Mean effective doses per exam type and their contributions to the collective dose were estimated on a sample of 56 % of those reported.
highest for adults over 40 y, regardless of location. For the age group 0–15 y, there is a relative higher frequency in CT examinations of the limbs and joints (8.6 %), head (4.3 %) and cervical spine (3.5 %). Regarding the distribution of CT examinations according to the sex of the patient reveals a balanced frequency, except abdomen and pelvis examinations where women hold 66.9 % of these exams. The mean effective doses per main conventional radiology and computed tomography procedures are presented in Tables 1 and 2. In 2012 were reported a total of 18 867 interventional radiology procedures. From examinations’ frequency analysis, it resulted that the largest share is angiography with almost 51 % of reported examinations, followed by coronary angioplasty (23.5 %), cerebral angiography (7 %), lower limb angiography (5.5 %) and abdominal angiography (4.8 %). From the reported data prevalent are exposures for age group of .40 y. It can be remarked for the 16- to 40-y age group, of all examinations for each type of angiographic procedure, a rate
ROMANIAN MEDICAL EXPOSURE Table 3. Mean effective dose for main interventional radiology procedures. Examination type
6.9+3.5 9.0+4.6 3.8+1.9 8.4+4.3 4.1+2.1 3.4+1.8 3.7+1.9 21.7+11.1 6.3+3.2 6.1+3.1 4.8+2.4
of almost 20 % for cerebral angiography and a rate of 18 % for pelvic angiography. The mean effective doses for interventional radiology procedures are presented in Table 3. A total of 619 479 dental radiological examinations were reported, which are classified as intraoral, panoramic and general examinations. It can be noticed a high frequency for intraoral dental radiographies, representing 75 % of reported examinations. In terms of distribution of dental radiological examinations of patients according to age, there is a slightly higher frequency for the age group of 16– 40 y compared with the age group of .40 y. Based on the data reported, collective effective doses were estimated for major radiological procedures, as well as their contributions to the total collective dose. From the analysis of contributions to the collective effective dose (Figure 1), the largest share is registered in the CT abdomen and pelvis region, followed by thorax CT and head CTexaminations. The following positions are fluoroscopic examinations of the thorax and gastrointestinal disease and also radiographic examination of the lumbar spine and thorax. For nuclear medicine, 17 088 diagnostic procedures were reported in 2012. Analysing the percentage distribution of frequencies, it can be observed that bone scintigraphy holds .50 % of all diagnostic procedures of nuclear medicine performed, followed by thyroid scintigraphy, PET-CT, renal scintigraphy and scintigraphy of thyroid function. From the point of view of the main contributions to nuclear medicine diagnostic procedures in collective effective dose (Figure 2), bone scintigraphy is the first, followed by PET-CT and thyroid scintigraphy. The annual collective effective dose per 1000 population for all X-ray-based radiology without dental radiology is 370 mSv per 1000 capita (371 mSv per 1000 capita with dental radiology) and 373.5 mSv per 1000 capita for all diagnostic procedures (including radiology and nuclear medicine).
Figure
1. Contributions to collective effective dose estimated for the main radiological procedures.
Figure 2. Contributions to collective effective dose estimated for the main nuclear medicine procedures.
CONCLUSIONS The main contributions to the collective dose of the radiological procedures are registered for CT abdomen and pelvis region, followed by thorax and head CT examinations. The radiographic examinations of the lumbar spine and thorax have an important contribution to the collective dose due to the large number of examinations
Page 3 of 4
Downloaded from http://rpd.oxfordjournals.org/ at University of Sheffield on September 11, 2015
Cardiac angiography Cerebral angiography Carotid angiography Abdominal angiography Pelvic angiography Lower limb angiography Upper limb angiography PTCA Carotid angioplasty Peripheral angioplasty Renal angioplasty
Mean effective dose (mSv)
O. GIRJOABA AND A. CUCU
REFERENCES 1. Order of the Health Ministry no. 1542/2006 concerning the registration and reporting patient doses. Official Gazette from Romania. Part I no. 1042 (2006). 2. Order of the Health Ministry no. 1003/2008 for approving the use of registration forms and reporting data on medical exposures to ionizing radiation. Official Gazette from Romania. Part I no. 393 (2008). 3. Hart, D., Jones, D. G. and Wall, B. F. Estimation of effective dose in diagnostic radiology from entrance surface dose and dose area product measurements. NRPB-R262, National Radiological Protection Board (1994). 4. International Commission of Radiological Protection. Radiation dose to patients from radiopharmaceuticals. ICRP Publication 80, 28(3) (1998).
Page 4 of 4
Downloaded from http://rpd.oxfordjournals.org/ at University of Sheffield on September 11, 2015
although they have relatively low effective dose per procedure. The contribution of interventional radiology to collective effective dose is not very important due to the low examination frequency. A major contribution to collective effective dose estimated for nuclear medicine diagnostic procedures is given by bone scintigraphy and PET-CT. The data regarding the dose received by the patients are incompletely reported for some CTexaminations (for example, Abdomen&Pelvis or Trunk) because legislation does not mention these exam types. As a result, the contributions to collective effective dose might change. The specific regulations must be improved.
