EYE LENS EXPOSURE TO MEDICAL STAFF PERFORMING ELECTROPHYSIOLOGY PROCEDURES: DOSE ASSESSMENT AND CORRELATION TO PATIENT DOSE.

The purpose of this study was to assess the patient exposure and staff eye dose levels during implantation procedures for all types of pacemaker therapy devices performed under fluoroscopic guidance and to investigate potential correlation between patients and staff dose levels. The mean eye dose during pacemaker/defibrillator implementation was 12 µSv for the first operator, 8.7 µSv for the second operator/nurse and 0.50 µSv for radiographer. Corresponding values for cardiac resynchronisation therapy procedures were 30, 26 and 2.0 µSv, respectively. Significant (p < 0.01) correlation between the eye dose and the kerma-area product was found for the first operator and radiographers, but not for other staff categories. The study revealed eye dose per procedure and eye dose normalised to patient dose indices for different staff categories and provided an input for radiation protection in electrophysiology procedures.

HAND DOSE EVALUATION OF OCCUPATIONALLY EXPOSED STAFF IN NUCLEAR MEDICINE.

Manipulation of unsealed radiation sources in nuclear medicine (NM) departments involves non-uniform exposure to staff and high skin doses to the upper extremities from direct and scattered radiations. Conducted studies have shown that the annual dose limits could be exceeded and the continuous dose monitoring of NM worker's hands is needed. The aim of this article is to show results of hand dose monitoring in terms of operational quantity Hp(0.07) for occupationally exposed NM workers to beta and gamma radiations in the largest NM centre in Serbia. Dose assessment was done by means of thermoluminescent ring dosemeters DXT-RAD (LiF:Mg,Ti). Monthly and annual doses were evaluated for a 5-y period (2010-14). Monitored NM staff was categorised according to the type of work, as nurses, radiographers, laboratory technicians and radiochemists. Performed evaluation showed that annual hand doses were within the annual limit for all staff categories, but further optimisation of working practice is needed.

Radiation exposure during X-ray examinations in a large paediatric hospital in Serbia.

Objective of this work is to evaluate radiation exposure from X-ray examinations in a large paediatric hospital in Serbia, including radiographic, fluoroscopic and computed tomography (CT) examinations in four age groups: 0-1, 1-5, 5-10 and 10-15 y. Incident air kerma was assessed for the following radiographies: chest (AP, PA, LAT), spine (AP, LAT), pelvis (AP), urinary tract (AP, PA) and skull (AP, PA, LAT). Kerma-area product was measured for the fluoroscopy examinations: barium swallow, barium meal, barium enema and micturating cystography. Dose in CT was assessed in terms of volume CT dose index and dose-length product for examinations of the head, chest and abdomen. The collected data were compared with other similar studies, which indicated a need to expand such survey to other paediatric hospitals in Serbia.

Performance of radiation survey meters in X- and gamma-radiation fields.

The aim of this work was to investigate the different types of radiation detectors commonly used for radiation protection purposes as survey meters. The study was performed on survey meters that use different detectors as ionisation chamber, Geiger Mueller (GM) counter and scintillation detector. For each survey meter, energy dependence and angular response in X- and gamma-radiation fields was tested. The following commercially available survey meters were investigated: ionisation chambers Victoreen 451P, Babyline 31 and VA-J-15A, Geiger counter MRK-M87, 6150 AD6 and FAG FH 40F2 and scintillation counter 6150 ADB. As a source of gamma radiation, (137)Cs and (60)Co were used whereas X-ray radiation fields were generated using an X-ray unit. The radiation characteristics of the survey meters were mostly in compliance with references estimated by standard IEC 1017-2. However, some of them showed larger deviation at lower energies. GM counters exhibit strong energy dependence for low-energy photons.

Radiation doses in adult computed tomography practice in Serbia: initial results.

This work presents initial data on radiation doses in adult computed tomography (CT) in Serbia. Data were collected in terms of CT dose index (CTDIvol) and dose length product (DLP) values for head, chest and abdomen examination. The range of CTDIvol values was found to be 53-98, 11-34 and 8.5-227 mGy whereas for DLP was 803-1066, 350-845 and 1066-3078 mGy cm(-1) for head, chest and abdomen examination, respectively. Except for abdomen on one CT unit, all estimated values were in line with the reported data. This work also presents simple method on how to reduce radiation doses when scanning head. Using axial (step-and-shot) instead of helical mode and decreasing tube current-time product leads to significant dose reduction. CTDIvol was decreased by 20 % whereas DLP was reduced for a factor 2.

IAEA survey of paediatric computed tomography practice in 40 countries in Asia, Europe, Latin America and Africa: procedures and protocols.

OBJECTIVE: To survey procedures and protocols in paediatric computed tomography (CT) in 40 less resourced countries. METHODS: Under a project of the International Atomic Energy Agency, 146 CT facilities in 40 countries of Africa, Asia, Europe and Latin America responded to an electronic survey of CT technology, exposure parameters, CT protocols and doses. RESULTS: Modern MDCT systems are available in 77 % of the facilities surveyed with dedicated paediatric CT protocols available in 94 %. However, protocols for some age groups were unavailable in around 50 % of the facilities surveyed. Indication-based protocols were used in 57 % of facilities. Estimates of radiation dose using CTDI or DLP from standard CT protocols demonstrated wide variation up to a factor of 100. CTDI(vol) values for the head and chest were between two and five times those for an adult at some sites. Sedation and use of shielding were frequently reported; immobilisation was not. Records of exposure factors were kept at 49 % of sites. CONCLUSION: There is significant potential for improvement in CT practice and protocol use for children in less resourced countries. Dose estimates for young children varied widely. This survey provides critical baseline data for ongoing quality improvement efforts by the IAEA.

Screen-film versus digital radiography of sacroiliac joints: evaluation of image quality and dose to patients.

The purpose of this paper is to evaluate the image quality and dose to patients in the radiography of sacroiliac joints and to perform a clinical comparative study of digital and conventional screen-film radiography. Routine radiography of sacroiliac joint was performed in 60 patients using digital and screen-film radiography. The visibility of five anatomical regions and the overall image quality were rated by experienced radiologists. Patient dose assessment in terms of entrance surface air kerma (ESAK) was performed. The digital system showed slightly improved visualisation of specific anatomical structures. Overall image quality was significantly better in the digital when compared with the screen-film imaging system. The average ESAK was 2.4 mGy in screen-film and 3.6 mGy in digital radiography. The digital radiography provided equal or better visibility of anatomical details and overall image quality, but on higher dose levels. Therefore, the practice on digital systems must be optimised.

IAEA survey of pediatric CT practice in 40 countries in Asia, Europe, Latin America, and Africa: Part 1, frequency and appropriateness.

OBJECTIVE: The purpose of this study was to assess the frequency of pediatric CT in 40 less-resourced countries and to determine the level of appropriateness in CT use. MATERIALS AND METHODS: Data on the increase in the number of CT examinations during 2007 and 2009 and appropriate use of CT examinations were collected, using standard forms, from 146 CT facilities at 126 hospitals. RESULTS: The lowest frequency of pediatric CT examinations in 2009 was in European facilities (4.3%), and frequencies in Asia (12.2%) and Africa (7.8%) were twice as high. Head CT is the most common CT examination in children, amounting to nearly 75% of all pediatric CT examinations. Although regulations in many countries assign radiologists with the main responsibility of deciding whether a radiologic examination should be performed, in fact, radiologists alone were responsible for only 6.3% of situations. Written referral guidelines for imaging were not available in almost one half of the CT facilities. Appropriateness criteria for CT examinations in children did not always follow guidelines set by agencies, in particular, for patients with accidental head trauma, infants with congenital torticollis, children with possible ventriculoperitoneal shunt malfunction, and young children (< 5 years old) with acute sinusitis. In about one third of situations, nonavailability of previous images and records on previously received patient doses have the potential to lead to unnecessary examinations and radiation doses. CONCLUSION: With increasing use of CT in children and a lack of use of appropriateness criteria, there is a strong need to implement guidelines to avoid unnecessary radiation doses to children.

Good reasons to implement quality assurance in nationwide breast cancer screening programs in Croatia and Serbia: results from a pilot study.

The purpose of this study is to investigate the need for and the possible achievements of a comprehensive QA programme and to look at effects of simple corrective actions on image quality in Croatia and in Serbia. The paper focuses on activities related to the technical and radiological aspects of QA. The methodology consisted of two phases. The aim of the first phase was the initial assessment of mammography practice in terms of image quality, patient dose and equipment performance in selected number of mammography units in Croatia and Serbia. Subsequently, corrective actions were suggested and implemented. Then the same parameters were re-assessed. Most of the suggested corrective actions were simple, low-cost and possible to implement immediately, as these were related to working habits in mammography units, such as film processing and darkroom conditions. It has been demonstrated how simple quantitative assessment of image quality can be used for optimisation purposes. Analysis of image quality parameters as OD, gradient and contrast demonstrated general similarities between mammography practices in Croatia and Serbia. The applied methodology should be expanded to larger number of hospitals and applied on a regular basis.

A radiological incident with a radioactive lightning rod source found in a vehicle used by film crewmembers: a case study.

An overview of radiological incident involving radiation source from a lightning rod (152Eu/154Eu), together with dose estimation for individuals exposed to ionising radiation is given in the paper. The cause of the incident was an orphaned source from a lightning rod. The dose received by individuals was assessed using a retrospective dosimetry technique, based on the information on behaviour of individuals and results of dose rate measurements in the vicinity of the source. Several people have been exposed to relatively high dose rates for an extended period of time. The conservatively estimated cumulative dose values for two categories of individuals were 50 and 40 mSv, respectively, which are significantly higher than annual dose limit for public exposure of 1 mSv. The need to identify radioactive sources incorporated in radioactive lightning rods, to maintain control and accountability and to remove and dispose of them properly along with appropriate record keeping in Serbia was highlighted. These activities would reduce the probability of occurrence of radiation incidents in Serbia.

Mammography radiation dose: initial results from Serbia based on mean glandular dose assessment for phantoms and patients.

The primary objective of this study is to investigate the actual mammography dose levels in Serbia and establish a baseline dose database for the future screening programme. The mean glandular dose (MGD) was assessed for standard size breast substituted by 45 mm polymethyl methacrylate (PMMA) phantom and imaged under typical clinical conditions at 30 screen-film mammography facilities. Average MGD was (1.9 +/- 1.0) mGy, with a range of 0.12-5.2 mGy. These results were used for the calculation of the initial diagnostic reference levels in mammography in Serbia, which was set to 2.1 mGy for a standard breast. At some facilities, high doses were observed and the assessed MGD was supplemented by a patient dose survey. MGD was measured for 53 women having a diagnostic mammography in cranio-caudal (CC) and mediolateral oblique (MLO) projections at the largest mammography facilities in Serbia. The parameters recorded were: age, compressed breast thickness, tube potential (in kV), tube loading (in mAs) and the MLO projection angle. The average MGD per image was 2.8 mGy for the CC projection and 4.3 mGy for the MLO projection. Dose to breast was compared with dose for PMMA phantoms of various sizes, assessed at the same facilities. The results have indicated that phantom dose values can assist in setting optimisation activities in mammography. Both phantom and patient dose values indicated unnecessary high doses in facilities with an extremely high mammography workload. For these facilities, urgent dose-reduction measures and follow-up actions were recommended.