Lawrence T. Dauer

Radiation Safety in the Treatment of Patients with Thyroid Diseases by Radioiodine 131I: Practice Recommendations of the American Thyroid Association

BACKGROUND Radiation safety is an essential component in the treatment of patients with thyroid diseases by ¹³¹I. The American Thyroid Association created a task force to develop recommendations that would inform medical professionals about attainment of radiation safety for patients, family members, and the public. The task force was constituted so as to obtain advice, experience, and methods from relevant medical specialties and disciplines. METHODS Reviews of Nuclear Regulatory Commission regulations and International Commission on Radiological Protection [corrected] recommendations formed the basic structure of the recommendations. Members of the task force contributed both ideas and methods that are used at their respective institutions to aid groups responsible for treatments and that instruct patients and caregivers in the attainment of radiation safety. There are insufficient data on long-term outcomes to create evidence-based guidelines. RESULTS The information was used to compile delineations of radiation safety. Factors and situations that govern implementation of safety practices are cited and discussed. Examples of the development of tables to ascertain the number of hours or days (24-hour cycles) of radiation precaution appropriate for individual patients treated with ¹³¹I for hyperthyroidism and thyroid cancer have been provided. Reminders in the form of a checklist are presented to assist in assessing patients while taking into account individual circumstances that would bear on radiation safety. Information is presented to supplement the treating physicians advice to patients and caregivers on precautions to be adopted within and outside the home. CONCLUSION Recommendations, complying with Nuclear Regulatory Commission regulations and consistent with guidelines promulgated by the National Council on Radiation Protection and Measurement (NCRP-155), can help physicians and patients maintain radiation safety after treatment with ¹³¹I of patients with thyroid diseases. Both treating physicians and patients must be informed if radiation safety, an integral part of therapy with ¹³¹I, is to be attained. Based on current regulations and understanding of radiation exposures, recommendations have been made to guide physicians and patients in safe practices after treatment with radioactive iodine.

Review and evaluation of updated research on the health effects associated with low-dose ionising radiation

While radiation health risks at low doses have traditionally been estimated from high-dose studies, we have reviewed recent literature and concluded that the mechanisms of action for many biological endpoints may be different at low doses from those observed at high doses; that acute doses <100 mSv may be too small to allow epidemiological detection of excess cancers given the background of naturally occurring cancers; that low-dose radiation research should use holistic approaches such as systems-based methods to develop models that define the shape of the dose-response relationship; and that these results should be combined with the latest epidemiology to produce a comprehensive understanding of radiation effects that addresses both damage, likely with a linear effect, and response, possibly with non-linear consequences. Continued research is needed to understand how radiobiology and epidemiology advances should be used to effectively model radiation worker risks.

Comparing Strategies for Operator Eye Protection in the Interventional Radiology Suite

PURPOSE To evaluate the impact of common radiation-shielding strategies, used alone and in combination, on scattered dose to the fluoroscopy operators eye. MATERIALS AND METHODS With an operator phantom positioned at the groin, upper abdomen, and neck, posteroanterior low-dose fluoroscopy was performed at the phantom patients upper abdomen. Operator lens radiation dose rate was recorded with a solid-state dosimeter with and without a leaded table skirt, nonleaded and leaded (0.75 mm lead equivalent) eyeglasses, disposable tungsten-antimony drapes (0.25 mm lead equivalent), and suspended and rolling (0.5 mm lead equivalent) transparent leaded shields. Lens dose measurements were also obtained in right and left 15° anterior obliquities with the operator at the upper abdomen and during digital subtraction angiography (two images per second) with the operator at the patients groin. Each strategys shielding efficacy was expressed as a reduction factor of the lens dose rate compared with the unshielded condition. RESULTS Use of leaded glasses alone reduced the lens dose rate by a factor of five to 10; scatter-shielding drapes alone reduced the dose rate by a factor of five to 25. Use of both implements together was always more protective than either used alone, reducing dose rate by a factor of 25 or more. Lens dose was routinely undetectable when a suspended shield was the only barrier during low-dose fluoroscopy. CONCLUSIONS Use of scatter-shielding drapes or leaded glasses decreases operator lens dose by a factor of five to 25, but the use of both barriers together (or use of leaded shields) provides maximal protection to the interventional radiologists eye.

Quality Improvement Guidelines for Recording Patient Radiation Dose in the Medical Record for Fluoroscopically Guided Procedures

ACR American College of Radiology, CRCPD Conference of Radiation Control Program Directors, FDA Food and Drug Administration, ICRU International Commission on Radiation Units and Measurements, IEC International Electrotechnical Commission, IRP interventional reference point, Ka,r total air kerma at the interventional reference point, NCRP National Council on Radiation Protection and Measurements, PKA kerma–area product, PSD peak skin dose, RDSR Radiation Dose Structured Report

Incidence of secondary cancer development after high-dose intensity-modulated radiotherapy and image-guided brachytherapy for the treatment of localized prostate cancer.

PURPOSE To report the incidence and excess risk of second malignancy (SM) development compared with the general population after external beam radiotherapy (EBRT) and brachytherapy to treat prostate cancer. METHODS AND MATERIALS Between 1998 and 2001, 1,310 patients with localized prostate cancer were treated with EBRT (n = 897) or brachytherapy (n = 413). We compared the incidence of SMs in our patients with that of the general population extracted from the National Cancer Institutes Surveillance, Epidemiology, and End Results data set combined with the 2000 census data. RESULTS The 10-year likelihood of SM development was 25% after EBRT and 15% after brachytherapy (p = .02). The corresponding 10-year likelihood for in-field SM development in these groups was 4.9% and 1.6% (p = .24). Multivariate analysis showed that EBRT vs. brachytherapy and older age were the only significant predictors for the development of all SMs (p = .037 and p = .030), with a trend for older patients to develop a SM. The increased incidence of SM for EBRT patients was explained by the greater incidence of skin cancer outside the radiation field compared with that after brachytherapy (10.6% and 3.3%, respectively, p = .004). For the EBRT group, the 5- and 10-year mortality rate was 1.96% and 5.1% from out-of field cancer, respectively; for in-field SM, the corresponding mortality rates were 0.1% and 0.7%. Among the brachytherapy group, the 5- and 10-year mortality rate related to out-of field SM was 0.8% and 2.7%, respectively. Our observed SM rates after prostate RT were not significantly different from the cancer incidence rates in the general population. CONCLUSIONS Using modern sophisticated treatment techniques, we report low rates of in-field bladder and rectal SM risks after prostate cancer RT. Furthermore, the likelihood of mortality secondary to a SM was unusual. The greater rate of SM observed with EBRT vs. brachytherapy was related to a small, but significantly increased, number of skin cancers in the EBRT patients compared with that of the general population.

Fears, feelings, and facts: interactively communicating benefits and risks of medical radiation with patients.

OBJECTIVE As public awareness of medical radiation exposure increases, there has been heightened awareness among patients and physicians of the importance of holistic benefit-and-risk discussions in shared medical decision making. CONCLUSION We examine the rationale for informed consent and risk communication, draw on the literature on the psychology of radiation risk communication to increase understanding, examine methods commonly used to communicate radiation risk, and suggest strategies for improving communication about medical radiation benefits and risk.

Radiation management for interventions using fluoroscopic or computed tomographic guidance during pregnancy: A joint guideline of the Society of Interventional Radiology and the Cardiovascular and Interventional Radiological Society of Europe with endorsement by the Canadian Interventional Radiology Association

Lawrence T. Dauer, PhD, CHP, Raymond H. Thornton, MD, Donald L. Miller, MD, John Damilakis, PhD, Robert G. Dixon, MD, M. Victoria Marx, MD, Beth A. Schueler, PhD, Eliseo Vano, PhD, Aradhana Venkatesan, MD, Gabriel Bartal, MD, Dimitrios Tsetis, MD, PhD, and John F. Cardella, MD, for the Society of Interventional Radiology Safety and Health Committee and the Cardiovascular and Interventional Radiology Society of Europe Standards of Practice Committee

Preparedness and Response for a Nuclear or Radiological Emergency

مملأل ةعارزلاو ةيذغلأا ةمظنم نم ةكرتشم ةياعرب ،ةيرذلا ةقاطلل ةيلودلا ةلاكولاو ،ةدحتملا ،ةيلودلا ةيرحبلا ةمظنملاو ،ةيلودلا لمعلا ةمظنمو ،يلودلا يندملا ناريطلا ةمظنمو ةمظنمل ةعباتلا ةيوونلا ةقاطلا ةلاكوو ،(لوبرتنلإا) ةيئانجلا ةطرشلل ةيلودلا ةمظنملاو لل ةحصلا ةمظنمو ،يداصتقلاا ناديملا يف ةيمنتلاو نواعتلا ةدھاعم ةمظنمو ،ةيكيرملأا نادلب قيسنتل ةدحتملا مملأا بتكمو ،ةئيبلل ةدحتملا مملأا جمانربو ،ةيوونلا براجتلل لماشلا رظحلا ةيناسنلاا نوؤشلا ، ةيوجلا داصرلأل ةيملاعلا ةمظنملاو ،ةيملاعلا ةحصلا ةمظنمو

Safety and efficacy of radioactive seed localization with I-125 prior to lumpectomy and/or excisional biopsy

PURPOSE To evaluate the safety and efficacy of pre-operative I-125 radioactive seed localization (RSL) as an alternative to wire localization (WL). METHODS A waiver was granted by the institutional review board for this HIPAA compliant study. Review of 356 consecutive single site nonpalpable mammographic and ultrasound guided I-125 RSLs done between November 2011 and April 2012 was conducted. Preoperative mammograms and specimen radiographs were reviewed for seed-target distance, lesion location, and target/seed removal. During a brief surgical training period, 35 of 356 women had both RSL and wire localization (WL) of the same lesion. Chi-square and single sample t-tests were used to compare margin status and duration of procedures. RESULTS Of the 356 RSLs, 303 (85.1%) were performed ≥ 1 day before surgery. Mammographic guidance was used in 330 (93%) and ultrasound in 26 (7%). Mean seed to target distance was 1mm (range 0-20mm); all targeted lesions were retrieved. In 31 women in whom mammographic guidance was used for both RSL and WL, median procedure time was not significantly different (RSL 9.0 min; WL 7.0 min; p=0.91), and median seed migration distance was <1mm (range 0-15 mm). No difference was detected between margin status with RSL alone versus WL (p=0.40 and p=0.65 for positive and <1mm margins, respectively). Two adverse events occurred requiring an additional wire/surgery. CONCLUSION RSL ≥ 1 day before surgery is a safe effective procedure for pre-operative localization, with few adverse events and surgical outcomes comparable to those achieved with wire localization.

Unprotected operator eye lens doses in oncologic interventional radiology are clinically significant: estimation from patient kerma-area-product data.

PURPOSE To correlate operator lens dose to patient-delivered kerma-area-product (P(KA)) to evaluate the usefulness of P(KA) as a surrogate for operator eye dose if collar monitor readings are unavailable or deemed unreliable, and to evaluate if unprotected lens dose is clinically significant. MATERIALS AND METHODS A retrospective review of peak skin doses for consecutive interventional radiology procedures performed during 2006 that had P(KA) estimates recorded was performed. Unshielded operator lens dose equivalents (LDE) were obtained from dosimetry monitors worn outside the collar shield of operating interventional radiologists. Operator LDE were correlated with patient P(KA). RESULTS Average LDE for 2006 was 35.7 mSv ± 32.7 (range 5.2-89.9 mSv). Patient-delivered P(KA) correlated directly with LDE, where 1 Gy cm(2) to the patient resulted in an average of 4.2 μSv to the unprotected eyes of the primary operator (r(2) = 0.7). CONCLUSIONS P(KA) may be useful as a surrogate measure of operator LDE if collar monitor readings are unavailable or deemed unreliable. For this study, the dose-effect threshold for cataract formation could be surpassed for some physicians within 11 years if lens dose-mitigating strategies are not routinely employed.