90Y-Labeled Resin Microsphere Spills: A Pilot Study to Determine Efficient Cleanup Practices.

90Y-labeled resin microspheres (RMs) are selective internal radiation therapy agents encased in microscopic resin spheres and then suspended in water for injection. The 90Y-RM package insert includes a recommended cleanup procedure for contamination spills. However, after a local hospital recently experienced a clinical incident, we explored the efficiency of the recommended cleanup procedure. The aim of this investigation was to demonstrate the effectiveness of different cleaning procedures and compare these with the recommended procedure. Methods: Controlled spills of 90Y-RMs were placed in the middle of 10 independent 0.09 m2 (1 ft2) tile sections of an existing vinyl tile floor. Each 0.09 m2 (1 ft2) area was surrounded by absorbent pads and was further contained within 0.28 m2 (3 ft2) 1.9-cm (¾ in)-thick plywood box enclosures. Three cleaning methods were implemented: damp paper towels (recommended procedure), adhesive paper, and a Swiffer wet mop (SWM). A calibrated Geiger counter was used to determine the maximum precleaning and maximum postcleaning exposure within the tile sections. Percentage exposure reduction was calculated for each cleaning trial, and because of the low sample size, nonparametric exact Kruskal-Wallis tests were used to determine differences in percentage exposure reduction among cleaning types. All statistical tests were conducted assuming a 5% chance of a type 1 error. Results: Both damp paper towels and the SWM were superior to adhesive paper (P = 0.0006 and P = 0.0005, respectively). There was no difference between damp paper towels and the SWM, nor did the variability of the cleanup methods differ (P = 0.6826 and P = 0.2501, respectively). Conclusion: Damp paper towels and the SWM decontaminated the controlled spills equally. This finding indicates that the SWM can effectively clean up 90Y contamination.

Radiation Hormesis: Historical and Current Perspectives.

The purpose of this article is to provide the reader with a better understanding of radiation hormesis, the investigational research that supports or does not support the theory, and the relationship between the theory and current radiation safety guidelines and practices. The concept of radiation hormesis is known to nuclear medicine technologists, but understanding its complexities and the historical development of the theory may bring about a better understanding of radiation safety and regulations.

Assessment of 99mTc-succimer residual activity using inert nonreactive syringes.

UNLABELLED: It has been widely reported that (99m)Tc-succimer adsorbs to plastic syringes significantly (up to 50%), often resulting in a lower administered dose than intended or inaccurate dosing. This adsorption rate is especially problematic in the pediatric population. To improve (99m)Tc-succimer dosing, we compared the adsorption of (99m)Tc-succimer with 2 types of syringes: silicone-coated syringes with nonlatex rubber on the plunger and inert nonreactive syringes with no silicone coating and no rubber on the plunger. METHODS: (99m)Tc-succimer kits were compounded according to the manufacturer's instructions. (99m)Tc-succimer doses (37-185 MBq) were drawn into 3-mL (silicone-coated or inert nonreactive) syringes in a 1-mL volume. Thirty min, 1 h, 2 h, and 4 h later, the syringes were assayed in a dose calibrator and assayed again after being emptied and rinsed with saline. In addition, we examined the data collected from 129 (99m)Tc-succimer doses administered in a pediatric department, in which 52 were dispensed in silicone-coated syringes and 77 were dispensed in inert nonreactive syringes. The doses were assayed immediately before and after injection. The syringes were flushed with normal saline. RESULTS: The labeling efficiency of the (99m)Tc-succimer kits was more than 95%. Residual activity left in the inert nonreactive syringes was 0.73% (SD, ±0.18%), which was significantly lower than the activity left in the silicone-coated syringes, 20.9% (SD, ±5.6%; P < 0.0001). The extent of adsorption did not change significantly between 30 min and 4 h of incubation. The clinical data showed that the residual activity was 30.6% (SD, ±12.5%) from doses dispensed in silicone-coated syringes and 6.38% (SD, ±2.95%) from doses dispensed in inert nonreactive syringes (P < 0.001). CONCLUSION: The inert nonreactive syringes had significantly less residual of (99m)Tc-succimer than silicone-based syringes, making it possible to accurately administer calculated doses of (99m)Tc-succimer to pediatric patients.

Extrinsic Versus Intrinsic Uniformity Correction for γ-cameras.

UNLABELLED: SPECT produces nuclear medicine images using a 3-dimensional diagnostic tool that eliminates the superimposition of adjacent structures, thus providing improved disease localization. Another method of uniformity correction-to use the complete capabilities of this tool-is discussed and evaluated in this article. The conventional method of intrinsic uniformity correction accounts only for nonuniformities within the γ-camera, excluding the collimator. If SPECT image quality is related to overall camera performance, then using an extrinsic uniformity correction method rather than an intrinsic method will improve image quality. METHODS: SPECT uniformity images were obtained using a SPECT phantom with application of intrinsic and extrinsic uniformity correction tables with 2 different γ-imaging systems. The image results were qualitatively assessed. RESULTS: Even with acceptable nonuniformity analyses, significant ring artifacts within the intrinsic uniformity-corrected images are observed, whereas the artifacts are considerably less significant with the extrinsic uniformity correction and disappear completely in some of these images. CONCLUSION: Extrinsic uniformity correction may significantly improve the overall image quality by taking into account nonuniformities that arise from the collimator. This method will result in fewer image artifacts and improved image quality, thereby improving patient care.

Exposure to technologists from preparing and administering therapeutic 131I: how frequently should we bioassay?

UNLABELLED: It is common for nuclear medicine technologists to perform procedures involving the preparation and administration of therapeutic levels of (131)I-sodium iodide. This small study looked at the question of how much internal exposure a technologist receives, on average, while preparing and administering a therapeutic dose of (131)I. METHODS: The study estimated technologists' intake of airborne (131)I by measuring air concentrations in their breathing zone during therapeutic procedures using (131)I capsules. The measurement was made by determining the radioactivity collected on a charcoal filter contained within a personal air sampler. The radioactivity captured by the charcoal filter was assessed in a well counter. RESULTS: Given these data, we were able to estimate the average (131)I intake of a technologist working in a general nuclear medicine department over a period of 1 y: about 19.2 kBq (0.52 µCi). CONCLUSION: The NRC requirement is to monitor workers who could inhale or ingest more than 185 kBq (5 µCi) of (131)I in 1 y. The results of this small study suggest internal exposure rates that are well below the annual Nuclear Regulatory Commission trigger limits for individual bioassay.

The effectiveness of decontamination products in the nuclear medicine department.

UNLABELLED: This study assesses the effectiveness of using everyday cleaning agents for the radioactive decontamination of wet (99m)Tc-pertechnetate spills in the nuclear medicine department. METHODS: Six cleaning agents (water, water and soap, alcohol, bleach, a commercial glass cleaner, and a commercial decontaminating agent) were analyzed for decontamination effectiveness for a wide range of surfaces (Formica, vinyl, vinyl-polyester, plastic, rubber, and polyester). RESULTS: Within the experiment, the contamination was removed to radioactivity levels of less than 1% of the original contamination level. CONCLUSION: The results indicate that for a range of surfaces, the investigated commercially available cleaning agents had little or no benefit over plain tap water when used to decontaminate (99m)Tc-pertechnetate spills.

Enhancing laboratory activities in nuclear medicine education.

Hands-on or active learning is important in nuclear medicine education. As more curricula start to require greater standards and as distance education expands, the effective use of laboratories in nuclear medicine education remains important in physics, instrumentation, and imaging but is often overlooked or underutilized. Laboratory exercises are a unique opportunity for nuclear medicine educators to facilitate students' critical thinking and problem-solving skills in a manner that often cannot occur in lectures or during online education. Given the lack of current laboratory tools and publications, there exists a requirement for nuclear medicine educators to develop, enhance, and monitor educational tools for laboratory exercises. Expanding technologies, variations in imaging and measurement systems, and the need to ensure that the taught technology is relevant to nuclear medicine students are issues faced by nuclear medicine educators. This article, based on principles of instructional design, focuses on the components and development of effective and enhanced nuclear medicine laboratories in our current educational environment.

Determination of hemolytic anemia through the study of (51)Cr red cell survival and splenic sequestration.

The use of (51)Cr-labeled red blood cells to determine erythrocyte survival in circulation is not a routine procedure. Data are acquired by frequent counting of small-volume blood samples to determine the rate of red cell survival over time. Results are entirely quantitative and can involve semilogarithmic graphing techniques. An accurate study can positively identify hemolytic anemia, a disorder characterized by premature destruction of erythrocytes. Additionally, anatomic sites of premature hemolysis will demonstrate a higher radioactive count than the background organ. This procedure review presents a dual survival and sequestration study positive for hemolytic anemia and hypersplenism in an 83-y-old man with systemic lupus erythematosus. (51)Cr red cell survival and splenic sequestration studies may be considered when clinical history and laboratory studies cannot establish a definitive diagnosis.

Technical review and considerations for a cerebrospinal fluid leakage study.

Within the past decade, published diagnostic algorithms for cerebrospinal fluid (CSF) leakage have included beta-2-transferrin analysis, rigid nasal endoscopy, high-resolution CT, CT cisternography, CT fluorescein lumbar puncture, and MRI but have not included the nuclear medicine CSF leakage study. However, some physicians still use this study today. This case report reviews the procedure and data calculations for the study. The presented case demonstrates how patient ingenuity in maintaining a compromised pledget for counting after sneezing contributed to the final diagnostic outcome. The patient was a 58-y-old man who presented with persistent nasal drainage and headaches, with no history of previous head trauma or surgery. The patient was referred to the nuclear medicine department for a CSF leakage study, which had positive findings and led to a final diagnosis of a large dural and skull defect posteriorly over the ethmoid sinuses.

Using personality type to improve clinical education effectiveness.

Many nuclear medicine technologists become clinical educators by chance, with little introduction to teaching methodologies and student learning styles. This means that most technologists teach students in the clinic by modeling the way in which they were taught in nuclear medicine school, a method that may not be effective for every student encountered. The purpose of this article is to examine how personality type can be used to improve clinical education effectiveness.