Review of common occupational hazards and safety concerns for nuclear medicine technologists

The purpose of this article is to address common occupational hazards and safety concerns of nuclear medicine technologists. There are many possible occupational hazards, but this review is intended to concentrate on common hazards and safety concerns. These include radiation safety issues and concerns about the possibility of developing latent diseases, such as eye cataracts or cancer; pregnant workers and radiation safety issues; biohazard concerns associated with patient body fluids; possible low-back pain from moving heavy equipment and performing patient transfers; and possible repetitive trauma disorders, such as carpal tunnel syndrome, from computer work. Suggestions are made regarding how to identify potential hazards and avoid them. After reading this article, nuclear medicine technologists should be able to explain the importance of the as-low-as-reasonably-achievable concept, discuss the possible effects of ionizing radiation on the adult and the developing fetus, list several basic principles to avoid injury to the back, list and describe the more common repetitive trauma disorders or injuries and how to avoid them, and list and describe the biohazard safety issues that nuclear medicine technologists face and how to develop policy to minimize exposure risk.     

A comprehensive approach to CT radiation dose reduction: one institution's experience

OBJECTIVE: The purpose of this article is to review the process of creating and implementing a comprehensive plan to reduce diagnostic radiation exposure at our institution. CONCLUSION: This process, which was initiated by forming a radiation dose reduction committee, addressed several different issues to improve patient safety. These include avoidance of unnecessary CT examinations, adjusting individual scanning parameters, revising protocols, use of shielding and dose monitoring, and implementing computer-based dose modulation software as well as educating referring physicians and radiologic technologists.     

Radiation dose to PET technologists and strategies to lower occupational exposure

OBJECTIVE: The use of PET in Australia has grown rapidly. We conducted a prospective study of the radiation exposure of technologists working in PET and evaluated the occupational radiation dose after implementation of strategies to lower exposure. METHODS: Radiation doses measured by thermoluminescent dosimeters over a 2-y period were reviewed both for technologists working in PET and for technologists working in general nuclear medicine in a busy academic nuclear medicine department. The separate components of the procedures for dose administration and patient monitoring were assessed to identify the areas contributing the most to the dose received. The impact on dose of implementing portable 511-keV syringe shields (primary shields) and larger trolley-mounted shields (secondary shields) was also compared with initial results using no shield. RESULTS: We found that the radiation exposure of PET technologists was higher than that of technologists performing general nuclear medicine studies, with doses averaging 771 +/- 147 and 524 +/- 123 microSv per quarter, respectively (P = 0.01). The estimated dose per PET procedure was 4.1 microSv (11 nSv/MBq). Injection of 18F-FDG contributed the most to radiation exposure. The 511-keV syringe shield reduced the average dose per injection from 2.5 to 1.4 microSv (P < 0.001). For the longer period of dose transportation and injection, the additional use of the secondary shield resulted in a significantly lower dose of radiation than did use of the primary shield alone or no shield (1.9 vs. 3.6 microSv [P = 0.01] and 3.4 microSv [P = 0.03], respectively). CONCLUSION: The radiation doses currently received by technologists working in PET are within accepted occupational health guidelines, but improved shielding can further reduce the dose.     

Radiological technologists view about dose reduction techniques in interventional radiology

We classified radiation exposure in interventional radiology into medical exposure and occupational exposure, and examined dose reduction and optimization from the point of view of radiological technologists. Radiologists and radiological technologists should share knowledge and information about dose reduction for patients and operators, and should maintain good relations and a good environment to further the management of dose reduction in clinical practice.     

Basic review of radiation biology and terminology

OBJECTIVE: The purpose of this paper is to review basic radiation biology and associated terminology to impart a better understanding of the importance of basic concepts of ionizing radiation interactions with living tissue. As health care workers in a field that utilizes ionizing radiation, nuclear medicine technologists are concerned about the possible acute and chronic effects of occupational radiation exposure. Technologists should have a clear understanding of what they are exposed to and how their safety could be affected. Furthermore, technologists should be knowledgeable about radiation effects so that they can adequately assuage possible patient fears about undergoing a nuclear medicine procedure. After reading this article, the nuclear medicine technologist will be familiar with: (a) basic radiation biology concepts; (b) types of interactions of radiation with living tissue, and possible effects from that exposure; (c) theoretical dose-response curves and how they are used in radiation biology; (d) stochastic versus nonstochastic effects of radiation exposure, and what these terms mean in relation to both high- and low-dose radiation exposure; and (e) possible acute and chronic radiation exposure effects.     

Extraneous adult fingers imaged on pediatric chest X-rays.

INTRODUCTION: The medical director of the pediatric intensive care unit (PICU) selected a collection of pediatric chest X-rays for a clinical audit. As an unrelated activity during the performance of this audit, the frequency of adult fingers visualized on the PICU chest X-rays was documented. METHODS: A clinical audit of 439 PICU chest X-rays was performed. The visualization of adult fingers on the radiographs was categorized into those fingers directly in the X-ray beam and those seen only in the partially coned area of the images. RESULTS: There were 43 instances (9.8%) in which adult fingers were directly exposed to the X-ray beam. Additionally, in 23 instances (5.2%), adult fingers were seen only in the partially coned area of the image. DISCUSSION: Professional standards of practice and radiation biology publications support the need to avoid occupational radiation exposure. Occupational health and safety and radiation safety regulations stipulate that operators of an X-ray emitting device, or technologists assisting in the operation of an X-ray emitting device, must distance themselves from the primary beam (minimum of 3 metres) during X-ray exposure. All attempts must be made not to expose other individuals during the acquisition of clinical images. These policies and practice standards must be reinforced to minimize the exposure of medical radiation technologists and other medical staff to radiation.     

Radiation safety precautions in the management of the hospitalized (131)I therapy patient

OBJECTIVES: The patient who has been dosed with therapeutic activities of (131)I for thyroid carcinoma poses a unique set of problems for nuclear medicine technologists in their efforts to reduce personnel exposure and control contamination spread. It is the objective of this article to: (a) review practical radiation safety concerns associated with hospitalized (131)I therapy patients; (b) propose preventative measures that can be taken to minimize potential exposure and contamination problems; and (c) review pertinent federal regulations that apply to patients containing therapeutic levels of radionuclides.     

How patients view the efficient use of diagnostic radiation.

Patients who are subjected to diagnostic x rays sometimes feel victimized by their dependence on large and very complex medical-care systems which treat them with over-all indifference. Some of these individuals are confronted with physicians and dentists who seem to order radiographs without giving reasons, as well as with employers and hospitals who require radiographs without seeming to "need" them. Other patients feel that they are acting as guinea pigs in training programs to technologists who appear to require retakes because they are working in a rapid and slapdash manner. When questioned by patients, personnel who are responsible for ordering or conducting x-ray examinations often inform them that someone else in the system is responsible for any unnecessary radiation exposure. Patients, dentists, physicians, radiologists, technologists, health physicists, and radiation control officers all bear responsibility for the efficient use of diagnostic radiation. People working in these capacities should cooperate more closely in the mutual sharing of responsibility for the well-being of patients.     

Occupational radiation monitoring at a large medical center in Japan

Occupational radiation dose monitoring is a method of ensuring that radiation levels are within the regulatory limits. Our objective in this study was to evaluate the radiation doses experienced by personnel at a radiology facility between 2001 and 2010. Overall, 2418 annual dose records for workers who were categorized into four occupational groups were analyzed. The groups included: (1) radiologists, (2) radiologic technologists, (3) nurses, and (4) other workers, who belong to other hospital departments, but who participate partially in some radiologic procedures. The dose distribution was found to be skewed, with 76 % of personnel having received no measurable doses and almost 2 % having received doses of more than 2 mSv. The weighted-average annual doses ranged from 0.13 to 0.57, 0.9 to 2.12, 0.01 to 0.19, and 0.01 to 0.09 mSv for the radiologists, radiologic technologists, nurses, and the other workers, respectively. The radiologic technologists received the highest radiation exposure among the four groups. It was found that the average annual doses were decreasing over time for the radiologists, radiologic technologists, and others, whereas they were increasing for the nurses. Nurses play an important role in assisting radiologists and patients during various radiologic procedures, which might have increased their average annual dose. During the 10-year period of this study, there was no incidence of a dose exceeding the annual dose limit of 20 mSv. Furthermore, there was no detectable neutron exposure.     

Low-dose radiation use in diagnostic imaging and cancer therapy settings

Current methods of radiation safety are characterized by age-old hypotheses that claim low doses of radiation, such as those received in diagnostic imaging and cancer treatment, increase the risk of cancer. The linear no-threshold hypothesis dates back to 70 years and has not been scientifically validated, yet it remains the driving force behind current regulatory policies concerning radiation exposure. The linear no-threshold hypothesis has birthed the “as low as reasonably achievable” concept that is commonly practiced in medical professions to limit radiation exposure. Both perpetuate an unscientific radiophobia stigma, while undermining the more likely result of stimulation of protective responses from the low doses of radiation. This article serves to reemphasize the fallacies of carcinogenic risk and to highlight the possible benefits of low-dose exposure in hopes of invalidating the concerns of physicians, the diagnostic imaging technologists, and patient populations that are subject to diagnostic imaging and cancer radiation therapies.     

Pediatric radiation protection

Children are more vulnerable to the late somatic effects and genetic effects of radiation than adults; therefore, every effort should be made to keep the dose as low as reasonably achievable, trying to retrieve the best possible information when performing indicated diagnostic tests. Minimizing radiation doses should be a concept applied in a chain of actions, starting from the appropriate choice of modern equipment in the Radiology Department. Pediatric-oriented protocols, especially with regard to CT protocols, regular quality assurance tests, and continuous training of staff involved, are important parts of this chain. Radiation protection rules should be meticulously applied in neonates and children. Justification of requested examinations, vetting of referrals for complex examinations, standardization of techniques and procedures, as well as optimization of protection measures are crucial components for ensuring minimization of radiation exposure. Special considerations include shielding of gonads, thyroid and lens, appropriate collimation, posteroanterior projections in females, added filtration, and grid removal. In addition, short exposure times, immobilization or sedation, entertainment, or distracting devices should be applied to eliminate patient motion. Departments can benefit from self-audits and re-evaluation of their procedures. The learning objectives of this review article comprise becoming familiar with the doses and risks associated with typical X-ray diagnostic examinations carried out in pediatric patients and getting accustomed to radiation protection methods and techniques that may be used to minimize exposure to pediatric patients during diagnostic X-ray examinations.     

Obesity and medical imaging challenges

Obesity is a medical and social condition that can affect radiology in a number of ways. Imaging equipment can be too small or limited in capacity. Determining the appropriate dose of contrast material may be difficult because guidelines do not always specify dose ranges for patients with above-average weight. Because longer exposure to radiation may be necessary to image obese patients, patients and radiologic technologists may be at risk for overexposure. Finally, medical image quality can be compromised by obesity, especially with ultrasonography.     

An examination of factors related to radiation protection practices

BACKGROUND: Radiation protection practices range from strict adherence to safety practices to complacency to unsafe procedures. Variations in compliance with safety practices can result in unnecessary radiation exposure to technologists and patients. OBJECTIVE: The objectives of this study were to advance the education and practice of the radiologic sciences by determining the degree of compliance with radiation safety practices as correlated to professional education, continuing education, years of employment in the radiologic sciences and work site. METHOD: A 32-item questionnaire was mailed to a national random sample of 2000 certified radiologic technologists. A return rate of 23.9% yielded 454 questionnaires suitable for analysis. RESULTS: Mean scores for knowledge of and compliance with safety practices were 82% and 72%, respectively. Performance on individual items ranged from 95% compliance to 34% compliance. Two independent variables (ie, years of employment in the radiologic sciences and work site) were significantly related (P < .05) to adherence to safety practices. CONCLUSION: Results indicated the need for educational and organizational interventions to increase compliance with safety practices.     

Can hand radiation absorbed dose from radiosynomicronvectomy be high?

Preparing and injecting radiopharmaceuticals containing beta emitting radionuclides, for radiosynovectomy (RS), implies the risk of exceeding the upper limit of skin and hand radiation absorbed dose, of 500 mSv/year to both technologists, who prepare and to doctors, who inject these radiopharmacuticals. A high number of RS treatments per day lack of effective radiation protection devices and skin contamination, increase the skin radiation absorbed dose. Pronounced dosimetric and radiation protection data for radionuclides used for RS, like yttrium-90, erbium-169, rhenium-186, dysprosium-165 and holmium-166, indicate the risk and the rationale for minimizing skin radiation doses to the hands of technologists and to doctors. Hands and skin radiation exposure is mainly due to direct beta radiation from yttrium-90 containing syringes. However skin contamination, may increase this dose independently of the radionuclide used for RS. Using a syringe shield with 5 mm perspex and holding the syringe by forceps, especially for the fixation of the needle to the syringe, beta radiation exposure to the finger tips may be reduced effectively. The use of radiation-resistant gloves reduces beta radiation dose to the skin only slightly, but offers a much better protection than Latex gloves for radioactive contamination. In this article we report measurements performed by us, underlining aspects of the most effective syringe shielding applied for RS. For reducing hands beta radiation exposure during RS the following are proposed: a) To use radiation protection devices, like manipulators and perspex syringe shields and b) Special training of the personnel for the proper handling of doses and for the removal of possible contamination from beta-emitting radionuclides and c) To use beta radiation personal ring dosimeters.     

Communicating radiation exposure: a simple approach

OBJECTIVE: The aim of this article is to provide a general method to help explain radiation exposure to patients presenting for nuclear medicine procedures. The concept is to convert the effective dose from any nuclear medicine procedure to the equivalent time in months or years to obtain the same effective dose from background radiation. METHODS: The effective dose of each common diagnostic nuclear medicine procedure was obtained from the literature and the corresponding background equivalent radiation time (BERT) was calculated assuming an average background radiation of 3 mSv/y. RESULTS: A table of the BERT has been compiled for common nuclear medicine procedures. CONCLUSION: The BERT table provides a simple approach to help physicians and technologists effectively communicate radiation exposure information and perhaps potential radiation risk.     

Clinical radiation management for fluoroscopically guided interventional procedures

The primary goal of radiation management in interventional radiology is to minimize the unnecessary use of radiation. Clinical radiation management minimizes radiation risk to the patient without increasing other risks, such as procedural risks. A number of factors are considered when estimating the likelihood and severity of patient radiation effects. These include demographic factors, medical history factors, and procedure factors. Important aspects of the patient's medical history include coexisting diseases and genetic factors, medication use, radiation history, and pregnancy. As appropriate, these are evaluated as part of the preprocedure patient evaluation; radiation risk to the patient is considered along with other procedural risks. Dose optimization is possible through appropriate use of the basic features of interventional fluoroscopic equipment and intelligent use of dose-reducing technology. For all fluoroscopically guided interventional procedures, it is good practice to monitor radiation dose throughout the procedure and record it in the patient's medical record. Patients who have received a clinically significant radiation dose should be followed up after the procedure for possible deterministic effects. The authors recommend including radiation management as part of the departmental quality assurance program.     

Radiation protection in pediatric imaging

The effects of medical radiation exposure in childhood can last a lifetime. As more American children are exposed to repeated diagnostic imaging examinations, concerns have been raised about the potential harm from early medical irradiation. Diagnostic imaging personnel have a responsibility to ensure strict and consistent observance of the "as low as reasonably achievable" (ALARA) principle. Radiation risks are greater for children, which makes strict compliance with radiation protection practices a public health imperative. Radiologic technologists play a central role in radiation protection for children. This Directed Reading reviews the biologic effects and risks of ionizing radiation among children and the use of radiation protection to minimize medical radiation doses in the pediatric population.     

Examination of occupational exposure to medical staff (primarily nurses) during 131I medical treatments

Recently, a new amendment to protect against radiation damage to humans has been enacted based on a 1990 recommendation by the ICRP. Consequently, the dose limits of occupational exposure to medical staff were cut down sharply compared with conventional readjustments. This amended bill, however, may be triggering a reduction in the number of applicants, which hope to engage in radiotherapy. This being the case, we measured the dose levels of the occupational exposure to medical staff (doctor's group, nuclear medicine technologist's group, nurse's group and pharmacist's group) from 1999 to 2002. Moreover, we investigated what the main factor is in nurse's occupational exposure to 131I. The highest doses of occupational exposure were 3.640 mSv to doctors, 7.060 mSv to nuclear medicine technologists, 1.486 mSv to nurses and 0.552 mSv to pharmacists. According to our results, it was clear that the highest doses in each group were far below the legally mandated upper limits of exposure doses. Although we investigated the correlations between the factors of nurse's occupational exposure to 131I with the number of inpatients, the amount of 131I and the number of servicing times for patients, there were no correlations found. Furthermore, to analyzing the factors in detail, it became clear that the main factor in the nurse's occupational exposure was due to the existence of patients who needed many more servicing times for their care than ordinary patients.     

A practical guide for protecting personnel, pregnant personnel, and patients during diagnostic radiography and fluoroscopy.

The following article presents a comprehensive overview of the practical aspects of radiation protection for diagnostic radiology. The topics discussed include background radiation levels, typical exposure levels for radiologic technologists, risk estimates, the relationship between dose and effect, dose limits, personnel monitoring, protective devices, gonadal shielding, and the immobilization of patients. Special attention has been given to the concerns of pregnant personnel and pregnant patients.     

Radiation dose reduction in chest CT—Review of available options

Computed tomography currently accounts for the majority of radiation exposure related to medical imaging. Although technological improvement of CT scanners has reduced the radiation dose of individual examinations, the benefit was overshadowed by the rapid increase in the number of CT examinations. Radiation exposure from CT examination should be kept as low as reasonably possible for patient safety. Measures to avoid inappropriate CT examinations are needed. Principles and information on radiation dose reduction in chest CT are reviewed in this article.