Influential Factors in the Preparation of 68Ga-DOTATATE.

Acceptable and reproducible radiochemical purity (RP) for 68Ga-DOTATATE was difficult to obtain with the NETSPOT kit because the manufacturer instructions lacked details on the heater or needles used. Methods: The drug was prepared in an International Organization for Standardization (ISO) 5 environment. Multiple dry baths and needle types were used to investigate the effects of reaction temperature and metal contamination, respectively. Temperature curves were obtained with a calibrated thermocouple. The influence of the accuracy of the NETSPOT reagent volume and its effect on outcome were investigated. Results: The AccuBlock dry bath required recalibration for the ISO 5 environment; after calibration, the temperature was stable (only ±0.1°C from the set point). When we followed package insert recommendations (dry bath temperature set to 98°C, reaction time of 8 min), the reaction temperature was 90.6°C. When Becton Dickinson needles were used for reconstitution, 15 of 18 runs (83%) did not meet the RP specification. However, B. Braun Medical needles achieved satisfactory and stable RP. When the 68Ga generator was eluted with 5.0 mL of 0.1 M hydrochloric acid (HCl), only 3.8-3.9 mL of eluate reached the reaction vial; this volume did not impact labeling (final pH was 3.8). The labeling success rate increased markedly if the 68Ga eluate was passed through a conditioned silica gel cartridge or if no cartridge was used; then, RP was more than 99%. HCl contact with the septum of the labeling vial reduced RP. Conclusion: The needle type and the temperature setting of the dry bath have critical roles in 68Ga-DOTATATE preparation. The AccuBlock dry bath has excellent stability and accuracy and can be used for reliable preparation. By using a conditioned silica gel cartridge or by eliminating the cartridge altogether, the RP is reliably high and stable.

Non-invasive visualization of tumor infiltrating lymphocytes in patients with metastatic melanoma undergoing immune checkpoint inhibitor therapy: a pilot study.

Early in the course of immunotherapy there is frequently a transient enlargement of tumor masses (pseudo-progression) due to tumor infiltration by TILs. Current clinical imaging modalities are not able to distinguished pseudo-progression from true tumor progression. Thus, patients often remain on treatment 4-8 weeks longer to confirm disease progression. Nuclear medicine offers the possibility to image immune cells and potentially discriminate pseudo-progression and progression. We conducted a pilot study in patients with metastatic melanoma receiving ipilimumab (IPI) or pembrolizumab (PEMBRO) to assess safety and feasibility of SPECT/CT imaging with 99mTc- interleukin-2 (99mTc-HYNIC-IL2) to detect TILs and distinguish between true progression from pseudo- progression. Scans were performed prior to and after 12w treatment. After labelling,99mTc-HYNIC-IL2 was purified and diluted in 10 mL of 5% glucose with 0.1% human serum albumin. Of the 5 patients (2 treated with IPI and 3 with PEMBRO) enrolled, two failed to complete the second scan as they discontinued IPI due grade 3 colitis (1 patient) or patient refusal after developing multiple toxicities attributed to IPI (1 patient). Following the first scan, one patient reported to have a grade 1 pruritus with grade 1 pain. No other toxicities attributed to the radiopharmaceutical infusion were reported. Metastatic lesions could be visualized by 99mTc-IL2 imaging and there was positive correlation between size and 99mTc-HYNIC-IL2 uptake, both before and after 12 weeks of therapy. The results of this pilot study demonstrate the safety and feasibility of 99mTc-IL2 imaging and has led to a number of hypotheses to be tested in future studies.

Rapid Instant Thin-Layer Chromatography System for Determining the Radiochemical Purity of 68Ga-DOTATATE.

The objective of this study was to develop instant thin-layer chromatography (ITLC) conditions for the determination of radiochemical purity of 68Ga-DOTATATE in a shorter time period than those stated in the NETSPOT (Advanced Accelerator Applications, Saint-Genis-Pouilly, France; AAA) kit package insert (PI). A faster ITLC system is needed to reduce the 48- to 50-min development time so that more radioactivity is available for single patient use and wait times are shorter in the event of kit failure. Methods: Variations of the PI mobile system were evaluated with microfiber chromatography paper impregnated with silica gel (ITLC-SG). After a more suitable mobile system was identified, evaluation began by attempting to shorten the 10-cm development distance to 7, 8, and 9 cm. Results: Experiments using variations of PI mobile phase showed that increasing the proportion of methanol in the mobile phase decreased development time. Additionally, if the ratio of 1 M ammonium acetate was reduced to 10% or less, retention factor values fall outside specification. Reducing the development distance shortened development time as expected; however, it also affected the resolution aspect of the radiochromatogram. Conclusion: The fastest developing ITLC system, which maintained resolution and peak shape, was methanol:1 M ammonium acetate (80:20 V/V) with ITLC-SG using a development distance of 8 cm.

Interventional Pain Management for Sacroiliac Tumors in the Oncologic Population: A Case Series and Paradigm Approach.

Introduction: Tumors invading the sacrum and/or ilium often represent incurable metastatic disease, and treatment is targeted toward palliation of symptoms and control of pain. As systemic opioid therapy is frequently inadequate and limited by side effects, a variety of interventional techniques are available to better optimize analgesia. Using six patients as a paradigm for interventional approaches to pain relief, we present a therapeutic algorithm for treating sacroiliac tumor-related pain in the oncologic population. Methods: We describe the use of ultrasound-guided proximal sacroiliac joint corticosteroid injection, sacroiliac lateral branch radiofrequency ablation, percutaneous sacroplasty, and implantable neuraxial drug delivery devices to treat malignant sacroiliac pain in six patients. Pre- and postprocedure numerical rating scale (NRS) pain scores, duration of pain relief, and postprocedure pain medication requirements were studied for each patient. Results: Each patient had marked improvement in their pain based on an average postprocedure NRS difference of six points. The average duration of pain relief was eight months. In all cases, opioid requirements decreased after the intervention. Discussion: Depending on tumor location, burden of disease, and patient preference, patients suffering from metastatic disease to the sacrum may find benefit from use of ultrasound-guided proximal sacroiliac joint corticosteroid injection, sacroiliac lateral branch radiofrequency ablation, percutaneous sacroplasty, dorsal column stimulator leads, and/or implantable neuraxial drug delivery devices. We provide a paradigm for treatment in this patient population.

Potential Ways to Address Shortage Situations of 99Mo/99mTc.

99mTc, the most common radioisotope used in nuclear medicine, is produced in a nuclear reactor from the decay of 99Mo. There are only a few aging nuclear reactors around the world that produce 99Mo, and one of the major contributors, the National Research Universal (Canada), ceased production on October 31, 2016. The National Research Universal produced approximately 40% of the world's 99Mo supply, so with its shut down, shortages of 99Mo/99mTc are expected. Methods: Nuclear pharmacies and nuclear medicine departments throughout the United States were contacted and asked to provide their strategies for coping with a shortage of 99Mo/99mTc. Each of these strategies was evaluated on the basis of its effectiveness for conserving 99mTc while still meeting the needs of the patients. Results: From the responses, the following 6 categories of strategies, in order of importance, were compiled: contractual agreements with commercial nuclear pharmacies, alternative imaging protocols, changes in imaging schedules, software use, generator management, and reduction of ordered doses or elimination of backup doses. Conclusion: The supply chain of 99Mo/99mTc is quite fragile; therefore, being aware of the most appropriate coping strategies is crucial. It is essential to build a strong collaboration between the nuclear pharmacy and nuclear medicine department during a shortage situation. With both nuclear medicine departments and nuclear pharmacies implementing viable strategies, such as the ones proposed, the amount of 99mTc available during a shortage situation can be maximized.

Ultrasound-Guided Serratus Plane Block for Treatment of Postmastectomy Pain Syndromes in Breast Cancer Patients: A Case Series.

Postmastectomy pain syndrome is common after surgical treatment for breast cancer and may be challenging to manage. Currently, there are a wide variety of approaches to treat this type of pain, including medications, physical therapy, and interventional procedures. However, because of the complexity of innervation of the breast, the serratus plane block may better target the web of nerves innervating the anterior chest wall including the breast. We present a case series of 8 patients who were successfully treated with serratus plane block for pain after treatment for breast cancer. We feel that this particular application for the serratus plane block deserves further investigation, as it is relatively easy to perform and has good clinical utility for this type of pain.

A retrospective review and treatment paradigm of interventional therapies for patients suffering from intractable thoracic chest wall pain in the oncologic population.

INTRODUCTION: Tumors invading the chest wall and pleura are often incurable, and treatment is targeted toward palliation of symptoms and control of pain. When patients develop tolerance or side effects to systemic opioid therapy, interventional techniques can better optimize a patient's pain. We performed a retrospective review of 146 patients from April 2004 to January 2014 who underwent diagnostic and therapeutic procedures for pain relief. Using four patients as a paradigm for neurolytic approaches to pain relief, we present a therapeutic algorithm for treating patients with intractable thoracic chest wall pain in the oncologic population. MATERIAL AND METHODS: For each patient, we describe the use of intercostal/paravertebral nerve blocks and neurolysis, pulsed radiofrequency ablation (PRFA) of the thoracic nerve roots, or intrathecal pump placement to successfully treat the patient's chest wall pain. Analysis of 146 patient charts is also performed to assess effectiveness of therapy. RESULTS: Seventy-nine percent of patients undergoing an intercostal nerve diagnostic blockade (with local anesthetic and steroid) stated that they had improved pain relief with 22% having prolonged pain relief (average of 21.5 days). Only 32% of successful diagnostic blockade patients elected to proceed to neurolysis, with a 62% success rate. Seven patients elected to proceed to intrathecal drug delivery. DISCUSSION: Intercostal nerve diagnostic blockade with local anesthetic and steroid may lead to prolonged pain relief in this population. Furthermore, depending on tumor location, we have developed a paradigm for the treatment of thoracic chest wall pain in the oncologic population.

Neurolytic transversus abdominal plane block with alcohol for long-term malignancy related pain control.

There have been several case reports in the literature of neurolytic transversus abdominis plane (TAP) blocks being used for malignant abdominal wall pain. However, most used phenol as a neurolytic agent. We found only a single case report by Sakamoto using alcohol for TAP neurolysis. Unfortunately this patient passed away only 5 days after performance of the block. We attempt to extend upon the existing literature by describing neurolytic TAP blockade outcomes using alcohol on 3 cancer patients with metastatic disease to the abdominal wall. Two of our 3 patients had colorectal cancer invading the abdominal musculature. The third patient had a metastatic neuroendocrine nodule in the left rectus muscle. In our case series, all 3 patients had sustained and significant (greater than 50%) relief of abdominal wall pain after performing TAP neurolysis using alcohol. Ultrasound guidance was used for all blocks. The concentration of alcohol used varied from 33% to 77% between patients. Duration of relief lasted between 17 days and 6 months. Opioid use either decreased or remained relatively stable for prolonged periods of time after neurolysis. Other than one patient with transient post-procedure pain related to alcohol injection, there were no significant complications. Addition of a depo steroid for diagnostic TAP blockade prior to neurolysis did not appear to extend or provide additional analgesia. Based on our observations, TAP neurolysis using alcohol also offers a feasible option for long-term control of malignant abdominal wall pain. Further investigation is needed to determine if alcohol offers any significant advantage compared with phenol.

Particle-size and radiochemical purity evaluations of filtered 99mTc-sulfur colloid prepared with different heating times.

UNLABELLED: Sentinel node lymphoscintigraphy using colloidal particles has become common practice at many institutions. The ideal particle size for colloids such as filtered (99m)Tc-sulfur colloid ((99m)Tc-FSC) in sentinel node studies is 15-100 nm. It is reported that the use of a reduced heating time during the reconstitution process results in an increased number of smaller particles (<30 nm). However, it is unclear whether these smaller particles (>15 nm) would be of benefit in sentinel node studies. This study sought to better define particle size by using electron microscopy, as well as to evaluate the radiochemical purity (RCP) of (99m)Tc-FSC at various time points after filtration. METHODS: One group of (99m)Tc-sulfur colloid ((99m)Tc-SC) preparations was reconstituted using the standard heating time of 5 min, and another group was prepared using a reduced heating time of 3 min. The (99m)Tc-SC preparations were passed through a 0.2-µm filter, and retained filter activity was measured. RCP values were collected at 0, 1, 3, and 6 h after filtration, and the particle sizes were measured at 0 and 6 h after filtration. RESULTS: Average RCP values (± SD) for (99m)Tc-FSC with 5-min heating were 98.4% ± 3.0% and 98.3% ± 1.8% for 0 h and 6 h, respectively (n = 6). Average RCP values for (99m)Tc-FSC with 3-min heating were 98.4% ± 4.1% and 96.9% ± 3.1% for 0 h and 6 h, respectively (n = 6). Electron microscopy data showed that median particle sizes for the 3-min heating at 0 and 6 h were 24 and 35 nm, respectively. Median particle sizes for the 5-min heating at 0 and 6 h were 29 and 27 nm, respectively. The proportion of particles within the ideal range for sentinel node lymphoscintigraphy was similar between the heating methods (91.1% for 3-min heating at 0 h and 88.8% for 5-min heating at 0 h, P = 0.1851). CONCLUSION: Our results indicate that although there are slight significant differences in RCP value, particle size, and particle number for (99m)Tc-FSC prepared using either a standard or a reduced heating time, both methods produce particles within the optimum range for sentinel node studies.

Bringing New PET drugs to clinical practice - a regulatory perspective.

The regulatory framework for radioactive drugs, in particular those used in positron emission tomography (PET) scans, has been gradually established since the release of the Food and Drug Administration Modernization Act in 1997. Various guidances specially tailored to accommodate special properties of PET drugs have been issued by the Food and Drug Administration (FDA) in order to ensure this valuable technology (i.e., PET molecular imaging) will continue to be available to patients and yet the safety and efficacy of PET drugs are well regulated so that public health will be protected. This article presents several key elements of this regulatory framework for PET drugs. New regulatory avenues proposed by the FDA to facilitate the research and development process to bring more new PET drugs to clinical practice, as well as to foster the opportunity of using "orphan" PET drugs in clinical practice are also discussed in this paper.

Comparison of FASTlab 18F-FDG production using phosphate and citrate buffer cassettes.

UNLABELLED: The objective of this research is to determine whether there are significant differences in the (18)F-FDG produced by either the phosphate or the citrate buffer cassettes in the FASTlab synthesizer. METHODS: Forty batches of (18)F-FDG were produced with each cassette and analyzed retrospectively. The analysis consisted of determining the mean radiochemical yield (RCY)-uncorrected and corrected for decay-radiochemical purity (RCP), pH, and residual solvent content (ethanol and acetonitrile). An independent t test (alpha error [α], 0.05) was performed to determine whether the differences were statistically significant. RESULTS: The mean decay-corrected RCYs for (18)F-FDG produced by phosphate and citrate cassettes were 82.9% ± 17.4% and 79.2% ± 5.0%, respectively. The uncorrected RCY was 57.5% ± 16.7% for phosphate- and 58.8% ± 6.0% for citrate-buffered (18)F-FDG, leading to a difference of 4.4% and P value of 0.11 for corrected RCY and a difference of 2.2% and P value of 0.32 for uncorrected RCY. Thus, the RCY differences are neither statistically nor clinically significant. The mean RCPs were 99.4% ± 0.2% for the phosphate-buffered (18)F-FDG and 99.0% ± 1.1% for the citrate-buffered (18)F-FDG. There was a 0.5% difference and a P value of 0.021, meaning that the difference was statistically significant. The average pHs for (18)F-FDG produced by phosphate and citrate buffer cassettes were 5.9 ± 0.1 and 5.3 ± 0.2, respectively, resulting in a 9.6% difference and a P value close to zero (2.6 × 10(-19))-a statistically significant difference. The difference between ethanol content was also dramatic. Phosphate-buffered (18)F-FDG contained 0.08% ± 0.02% ethanol, whereas the citrate-buffered (18)F-FDG contained 0.20% ± 0.07%. No difference was found in the acetonitrile content of the 2 cassettes. CONCLUSION: The differences in yield between cassettes are due to statistical variability. The results confirm our hypothesis that there is no significant difference in RCY. The differences seen in the statistically significant data (those with a P value > 0.05) turn out to be insignificant in a real-world setting because all values fell within the limits set by the United States Pharmacopeia and Food and Drug Administration. Therefore, determining which cassette to use is a matter of the preference of the institution.

Operational characteristics of (11)c-choline positron emission tomography/computerized tomography for prostate cancer with biochemical recurrence after initial treatment.

PURPOSE: We examined the performance of (11)C-choline positron emission tomography/computerized tomography for its ability to delineate prostate cancer distribution and extent after initial therapy. MATERIALS AND METHODS: A consecutive series retrospective review was performed of all patients with prostate cancer who were evaluated using (11)C-choline positron emission tomography/computerized tomography from September 2007 to November 2010 at the Mayo Clinic. Statistical analysis was performed to determine the sensitivity, specificity, positive predictive value, negative predictive value and prostate specific antigen threshold for the detection of recurrent lesions. RESULTS: In the study period 176 patients with biochemical recurrence after primary treatment failure underwent (11)C-choline positron emission tomography/computerized tomography. Using patient based analysis (11)C-choline positron emission tomography yielded a sensitivity, specificity, positive predictive value and negative predictive value of 93%, 76%, 91% and 81%, respectively. Of the 176 positron emission tomography/computerized tomography scans performed 56 (32%) were deemed clinically useful as defined by the ability to identify lesions not delineated using conventional imaging, thereby prompting changes in clinical management. The optimal prostate specific antigen for lesion detection was 2.0 ng/ml. On multivariate analysis prostate specific antigen at positron emission tomography (HR 1.37, p = 0.04) and clinical stage at initial diagnosis of prostate cancer (HR 5.19, p = 0.0035) were significant predictors of positive (11)C-choline positron emission tomography/computerized tomography. CONCLUSIONS: (11)C-choline positron emission tomography/computerized tomography performs well in men with biochemical recurrence after primary treatment failure. The optimal prostate specific antigen value for lesion detection is approximately 2.0 ng/ml. We found that (11)C-choline positron emission tomography/computerized tomography substantially enhances the rate of prostate cancer lesion detection by approximately 32% beyond what can be garnered using conventional imaging techniques and at a lower prostate specific antigen value.

Minimizing human error in radiopharmaceutical preparation and administration via a bar code-enhanced nuclear pharmacy management system.

UNLABELLED: The objective of this project was to ensure correct radiopharmaceutical administration through the use of a bar code system that links patient and drug profiles with on-site information management systems. This new combined system would minimize the amount of manual human manipulation, which has proven to be a primary source of error. The most common reason for dosing errors is improper patient identification when a dose is obtained from the nuclear pharmacy or when a dose is administered. A standardized electronic transfer of information from radiopharmaceutical preparation to injection will further reduce the risk of misadministration. METHODS: Value stream maps showing the flow of the patient dose information, as well as potential points of human error, were developed. Next, a future-state map was created that included proposed corrections for the most common critical sites of error. Transitioning the current process to the future state will require solutions that address these sites. To optimize the future-state process, a bar code system that links the on-site radiology management system with the nuclear pharmacy management system was proposed. A bar-coded wristband connects the patient directly to the electronic information systems. RESULTS: The bar code-enhanced process linking the patient dose with the electronic information reduces the number of crucial points for human error and provides a framework to ensure that the prepared dose reaches the correct patient. Although the proposed flowchart is designed for a site with an in-house central nuclear pharmacy, much of the framework could be applied by nuclear medicine facilities using unit doses. CONCLUSION: An electronic connection between information management systems to allow the tracking of a radiopharmaceutical from preparation to administration can be a useful tool in preventing the mistakes that are an unfortunate reality for any facility.

Evaluation of compatibility and stability of filtered 99mTc-sulfur colloid when combined with fluorescent indocyanine green dye.

UNLABELLED: It is a common practice to administer dyes and radiopharmaceuticals separately for the localization of sentinel nodes in patients with biliary tract malignancies. The objective of this study was to evaluate the chemical properties and particle size of filtered (99m)Tc-sulfur colloid before and after it is combined with indocyanine green for injection. This study also evaluated the compatibility and stability of the two when combined, for the possibility of a single injection. METHODS: (99m)Tc-sulfur colloid was prepared according to the package insert, and the final preparation was passed through a sterile 0.2-µm filter. Green dye was also prepared as per the package insert. In a sterile syringe, 0.25 mL of 14.8-MBq (400-µCi) filtered (99m)Tc-sulfur colloid was mixed with 0.25 mL of 1.25-mg green dye in a 1:1 proportion for a total volume of 0.50 mL. The radiochemical purity and pH of filtered (99m)Tc-sulfur colloid were obtained immediately and at 1 and 2 h after preparation. Particle size was analyzed using an electron microscope immediately and at 2 h. RESULTS: The average radiochemical purity was 97.6% ± 2.0% (n = 51). The average pH was 5.56 ± 0.26 (n = 51). Evaluation of the particle size of filtered (99m)Tc-sulfur colloid with the green dye was determined by electron microscopy to be an average of 53 ± 30 nm (n = 365) at 0 h and 60 ± 35 nm (n = 303) at 2 h. This was compared with filtered (99m)Tc-sulfur colloid without the green dye, which averaged 71 ± 41 nm (n = 41). Measurements of unfiltered (99m)Tc-sulfur colloid were recorded at 253 ± 192 nm (n = 21) for additional comparisons. CONCLUSION: The chemical properties and particle size of filtered (99m)Tc-sulfur colloid were not affected by the addition of the green dye; thus, combination of filtered (99m)Tc-sulfur colloid and green dye in the same syringe for administration is suitable.

Stability evaluation of (18)F-FDG at high radioactive concentrations.

UNLABELLED: The objective of our study was to determine the concentration of ethanol, a known radiolytic stabilizer, needed to maintain stability for 12 h at an (18)F-FDG concentration of 19.7-22.6 GBq/mL (533-610 mCi/mL) at the end of synthesis (EOS). METHODS: (18)F(-) was formed by the (18)O(p, n)(18)F reaction using 16.5-MeV protons on a cyclotron. (18)F-FDG was synthesized using a synthesis platform. The final product was formulated in 15 mL of phosphate buffer. The synthesis took 22 min, delivering up to 336.7 GBq (9.1 Ci) of (18)F-FDG at the EOS. A series of 9 runs, 19.7-22.6 GBq/mL (533-610 mCi/mL), was completed. Three runs were doped with 0.1% ethanol, 3 with 0.2% ethanol, and 3 with no ethanol added. The radiochemical purity (RCP) was tested at about 1-h increments over a 12-h period. RCP was found by radio-thin-layer chromatography using aluminum-backed silica gel plates, acetonitrile, and water 90:10. An (18)F-FDG standard of 1 mg/mL was used to confirm radiochemical identity. The chromatography plates were analyzed on a radio-thin-layer chromatograph using a ß-detector. Residual solvents were also tested using gas chromatography with flame ionization detection and a capillary column. Other quality control measurements performed were pH and appearance. RESULTS: The 3 runs doped with 0.1% ethanol failed RCP after 5 h. The 3 runs using an ethanol concentration of 0.2% maintained stability through 12 h beyond the EOS. For these 3 runs, the radiolytic impurities were relatively constant at 6.1% ± 0.7% after 3 h. The runs using no ethanol failed RCP at 1 h. The pH varied between 5.3 and 6.1. Visual inspection was always clear and particulate-free. For the runs with 0.2% and 0.1% ethanol, the residual solvents were 0.21% ± 0.02% and 0.10% ± 0.02%, respectively. Regardless of ethanol concentration, chemical purity and identity passed quality control measurements. CONCLUSION: With the addition of 0.2% ethanol, (18)F-FDG (19.7-22.6 GBq/mL [533-610 mCi/mL]) kept stability through 12 h beyond the EOS. Each run passed stability parameters related to radiolysis-that is, radiochemical identity and RCP, chemical purity and identity, appearance, pH, and residual solvents.

A rapid radiochemical purity testing method for 99mTc-tetrofosmin.

UNLABELLED: The standard radiochemical purity (RCP) testing method for (99m)Tc-tetrofosmin as described in the package insert requires extensive time (20-30 min) and considerable skill to achieve accurate results. Additionally, the instant thin-layer chromatography strip impregnated with silica gel (2x20 cm) used in the standard method will not be commercially available in the future. The purpose of this study was to evaluate whether a method developed by our laboratory for RCP testing of (99m)Tc-sestamibi could also be used as an alternative method for the RCP assay of (99m)Tc-tetrofosmin. METHODS: The alternative RCP testing system consisted of a precut paper strip (1x8.5 cm) from solvent saturation pads (Pall Corp.) as the stationary phase, with 1:1 chloroform:tetrahydrofuran used as the mobile phase. To validate the reliability of the alternative method, RCP values from 17 kit preparations were compared with the 2 methods. Kits were reconstituted according to the package insert instructions, and 4 additions of (99m)Tc-sodium pertechnetate were purposely added to create trials with RCP values below the accepted limit of 90% purity. RESULTS: Two hundred four trials (100 of which were replicated) were run from the 17 kit preparations. Sixty-four (31%) of the 204 trials were below 90% purity based on the standard method. The overall agreement between the standard and alternative methods was 94% (192/204). The sensitivity of the alternative method for unacceptable RCP limits was 86% (55/64), and the specificity for acceptable RCP values was 98% (137/140). The agreement between the replicated trials of the alternative method was 99% (99/100), and for the standard method it was 92% (92/100). CONCLUSION: The standard method proved to be a much slower method and requires much more precision and attention. The alternative method is much faster, is easier, requires less attention to the solvent-development process, and can be used for RCP testing of both (99m)Tc-tetrofosmin and (99m)Tc-sestamibi. Furthermore, the stationary phase is much more readily available, is not moisture-sensitive, and is less susceptible to operator technique. Our method is accurate in determining the RCP value of (99m)Tc-tetrofosmin and is a better RCP testing method for (99m)Tc-tetrofosmin.

Mayo Clinic approaches to meet United States Pharmacopeia <797> requirements for facility design and environmental controls of nuclear pharmacy.

UNLABELLED: According to the United States Pharmacopeia (USP) General Chapter <797> (USP <797>), "Pharmaceutical Compounding-Sterile Preparations," the compounding facility must be physically designed and environmentally controlled to minimize airborne contamination from contacting critical sites. The goal of the project was to evaluate the appropriateness and effectiveness of our approaches in meeting <797> requirements. METHODS: USP <797> standards, radiation safety concerns, and work-flow patterns were the focal points in our assessment of 4 laboratories: 2 nuclear pharmacy laboratories that engage in preparing sterile (low-, medium-, and high-risk levels), nonsterile, or possible hazardous radioactive drugs and 2 other laboratories in which only low-risk-level preparations are involved. RESULTS: Each laboratory was constructed with a physically separated International Organization for Standardization Class 7 anteroom and clean room to allow us to maintain an appropriate air quality, a consistent operation, and a desirable flexibility. An isolated area within the laboratory was designated for preparing nonsterile products. Higher air change per hour was used in the areas with higher traffic or smaller space. Lead-lined biological safety cabinets (BSCs) were segregated and used depending on the risk category of the preparations. In 1 laboratory, the exhaust flow for the BSC was too great, and a lead-lined compounding aseptic containment isolator (CACI) was installed. Air in the BSC and CACI was 100% exhausted to the atmosphere. 99Mo/99mTc generators were placed in the negative-pressure clean room to ensure a more efficient operation and cleaner air environment. Clean-room equipment (i.e., keyboards, printers, and telephones) was installed, and refrigerators or freezers and the central-processing unit of each computer were placed outside clean room. CONCLUSION: Our wide-range preparations of sterile, nonsterile, or potential hazardous radiopharmaceuticals, coupled with the limited space of each laboratory and existing antiquated mechanical systems, presented a challenge. Nevertheless, we successfully remodeled each nuclear pharmacy laboratory to meet USP <797> requirements for facility design and environmental controls.

Comparison of the EZ-Cap recapper with the Mayo recapper for the prevention of needlesticks.

UNLABELLED: The purpose of this project was the development of a device that improves the design of our current capping block, the Mayo recapper. The major challenges for design and improvement included creating a device that is simple to use and can be applied throughout our department. We wanted a recapper device that increased safety and minimized the potential for needlesticks. Simplicity was another important factor, along with versatility and low cost. A new recapper, called EZ-Cap, was developed, and a comparison study was conducted to evaluate the pros and cons of the EZ-Cap recapper and the Mayo recapper. METHODS: Nuclear medicine technologists (n = 10) in our department used each device when administering patient injections. At the conclusion of their patient injection rotation, they recorded on a survey sheet the pros and cons of each device. The results of this survey were used to evaluate the effectiveness, comfort level during use, and safety of each recapping device. We used a 2-level scoring system to help determine which device was more favorable. The first level focused on comfort and convenience and was given a score of +1 or -1. The second level focused on safety and was given a score of +2 or -2. Because we believed that safety was a high priority for our capping blocks, this level received a higher score than the first level. RESULTS: The Mayo recapper was the device preferred by 9 of 10 technologists surveyed. The EZ-Cap recapper had several technical issues that made it difficult to use and that could potentially lead to safety concerns. According to our scoring system, the Mayo recapper received a score of +9 for its pros and -4 for its cons. By comparison, the EZ-Cap recapper received a score of +7 for its pros and -16 for its cons. CONCLUSION: Our results show that the Mayo recapper was the device of choice because its pros outweighed its cons. However, we will continually improve the effectiveness of the Mayo recapper to prevent needlesticks.

Safety devices for delivery of radioactive iodine.

For clinical applications, liquid 131I is more cost-effective and flexible than capsules for diagnostic and therapeutic dosing of the thyroid gland. However, the liquid is potentially a contamination hazard because of possible spilling by a patient or staff member. The objective of this study was to design a safety system for delivering therapeutic doses of liquid 131I that would not only minimize potential contamination spill hazards but also reduce radiation exposure to patients and staff during the therapeutic dosing process. A plastic vial with a secured top and tube to allow drinking was placed in a lead container with a screw-on lid. A dosing tray holds the lead-encased vial directly in front of the patient, further reducing the risk of spillage. The tray has a peripheral lip to contain any liquid that might spill. This height-adjustable tray is temporarily fastened to the chair's armrest. After the dose is administered, 20 mL of distilled water is injected into the shielded vial through a 1.5-mm orifice in the cap. The orifice is a vent to eliminate any vacuum created while drinking. The water rinses the vial so the patient receives the entire dose after the second drink. Our shielded spill-proof safety cup effectively seals the contents, reducing the risk of spillage and minimizing radiation exposure to patients and staff. Impact testing demonstrated only minimal leakage when the cup was dropped from a 1-m height. Our shielded cup and tray assembly could be implemented efficiently and economically into the clinical setting with minimal expense.