Assessing and Reducing Positron Emission Tomography/Computed Tomography Radiotracer Infiltrations: Lessons in Quality Improvement and Sustainability.

PURPOSE: Accurate administration of radiotracer dose is essential to positron emission tomography (PET) image quality and quantification. Misadministration (infiltration) of the dose can affect PET/computed tomography results and lead to unnecessary or inappropriate treatments and procedures. Quality control efforts ensure accuracy of the administered dose; however, they fail to ensure complete delivery of the dose into the patient's circulation. We used new technology to assess and improve infiltration rates and evaluate sustainability. METHODS: Injection quality was measured, improved, and sustained during our participation in a multicenter quality improvement project using Define, Measure, Analyze, Improve, Control methodology. Five technologists monitored injection quality in the Measure and Improve phases. After seven new technologists joined the team in the Control phase, infiltration rates were recalculated, controlling for technologist- and patient-level correlations, and comparisons were made between these two groups of technologists. RESULTS: In the Measure phase, five technologists monitored 263 injections (13.3% infiltration rate). Nonantecubital fossa injections had a higher probability of infiltration than antecubital fossa injections. After implementing a quality improvement plan (QIP), the same technologists monitored 278 injections in the Improve phase (2.9% infiltration rate). The 78% decrease in infiltration rate was significant (P < .001) as was the decrease in nonantecubital fossa infiltrations (P = .0025). In the Control phase, 12 technologists monitored 1,240 injections (3.1% infiltration rate). The seven new technologists had significantly higher rates of infiltration (P = .017). CONCLUSION: A QIP can significantly improve and sustain injection quality; however, ongoing monitoring is needed as new technologists join the team.

Quality Improvement Initiatives to Assess and Improve PET/CT Injection Infiltration Rates at Multiple Centers.

PET/CT radiotracer infiltration is not uncommon and is often outside the imaging field of view. Infiltration can negatively affect image quality, image quantification, and patient management. Until recently, there has not been a simple way to routinely practice PET radiopharmaceutical administration quality control and quality assurance. Our objectives were to quantify infiltration rates, determine associative factors for infiltration, and assess whether rates could be reduced at multiple centers and then sustained. Methods: A "design, measure, analyze, improve, and control" quality improvement methodology requiring novel technology was used to try to improve PET/CT injection quality. Teams were educated on the importance of quality injections. Baseline infiltration rates were measured, center-specific associative factors were analyzed, team meetings were held, improvement plans were established and executed, and rates remeasured. To ensure that injection-quality gains were retained, real-time feedback and ongoing monitoring were used. Sustainability was assessed. Results: Seven centers and 56 technologists provided data on 5,541 injections. The centers' aggregated baseline infiltration rate was 6.2% (range, 2%-16%). On the basis of their specific associative factors, 4 centers developed improvement plans and reduced their aggregated infiltration rate from 8.9% to 4.6% (P < 0.0001). Ongoing injection monitoring showed sustainability. Significant variation was found in center- and technologist-level infiltration rates (P < 0.0001 and P = 0.0020, respectively). Conclusion: A quality improvement approach with new technology can help centers measure infiltration rates, determine associative factors, implement interventions, and improve and sustain injection quality. Because PET/CT images help guide patient management, the monitoring and improvement of radiotracer injection quality are important.

Technical Note: Characterization of technology to detect residual injection site radioactivity.

PURPOSE: Each year in the United States, approximately 18.5 million nuclear medicine procedures are performed. Various quality control measures are implemented to reduce image errors and improve quantification of radiotracer distribution. However, there is currently no routine or timely feedback about the quality of the radiotracer injection. One potential solution to evaluate the injection quality is to place a topical scintillation sensor near the injection site to record the presence of residual activity. This work investigates a sensor design for identification of injections where the prescribed radioactive activity is not fully delivered into the patient's circulation (an infiltration). METHODS: The sensor consists of a single unshielded bismuth germanate (BGO) crystal (3 mm × 3 mm × 3 mm). Using radioactive sources with gamma energies that span the range commonly used in nuclear medicine, we quantified energy resolution and linearity. Additionally, we computed sensitivity by comparing the calculated incident activity to the activity measured by the sensor. Sensor output linearity was calculated by comparing measured data against the radioactive decay of a source over multiple half-lives. The sensor incorporates internal temperature feedback used to compensate for ambient temperature fluctuations. We investigated the performance of this compensation over the range of 15°C-35°C. RESULTS: Energy spectra from four sensors were used to calculate the energy resolution: 67% for 99m Tc (141 keV), 67% for 133 Ba (344 keV), 42% for 18 F (511 keV), and 32% for 137 Cs (662 keV). Note that the energy used for 133 Ba is a weighted average of the three photon emissions nearest to the most abundant (356 keV). Sensor energy response was linear with a difference of 1%-2% between measured and predicted values. Energy-dependent detector sensitivity, defined as the ratio of measured photons to incident photons for a given isotope, decreased with increasing photon energy from 55.4% for 99m Tc (141 keV) to 3.3% for 137 Cs (662 keV). Without compensation, error due to temperature change was as high as 53%. Temperature compensation reduced the error to less than 1.4%. Sensor output linearity was tested to as high as 210 kcps and the maximum magnitude error was 4%. CONCLUSIONS: The performance of the sensor was adequate for identification of excessive residual activity at an injection site. Its ability to provide feedback may be useful as a quality control measure for nuclear medicine injections.

Usefulness of Topically Applied Sensors to Assess the Quality of 18F-FDG Injections and Validation Against Dynamic Positron Emission Tomography (PET) Images.

Background: Infiltrations of 18F-fluorodeoxyglucose (FDG) injections affect positron emission tomography/computed tomography (PET/CT) image quality and quantification. A device using scintillation sensors (Lucerno Dynamics, Cary, NC) provides dynamic measurements acquired during FDG uptake to identify and characterize radioactivity near the injection site prior to patient imaging. Our aim was to compare sensor measurements against dynamic PET image acquisition, our proposed reference in assessing injection quality during the uptake period. Methods: Subjects undergoing routine FDG PET/CT imaging were eligible for this Institutional Review Board approved prospective study. After providing informed consent, subjects had sensors topically placed on their arms. FDG was injected into subjects' veins directly on the PET imaging table. Dynamic images of the injection site were acquired during 45 min of the uptake period. These dynamic image acquisitions and subjects' routine standard static images were evaluated by nuclear medicine physicians for abnormal FDG accumulation near the injection site. Sensor measurements were interpreted independently by Lucerno staff. Dynamic image acquisition interpretation results were compared to the sensor measurement interpretations and to static image interpretations. Results: Twenty-four subjects were consented and enrolled. Data from 21 subjects were gathered. During dynamic image acquisition review, physicians interpreted 4 subjects with no FDG accumulation at the injection site, whereas 17 showed evidence of accumulation. In 10 of the 17 cases that showed FDG accumulation, the FDG presence at the injection site resolved completely during uptake corresponding to venous stasis, the temporary sequestration of blood from circulation. Static image interpretation agreed with dynamic images interpretation in 11/21 (52%) subjects. Sensor measurement interpretations agreed with the dynamic images interpretations in 18/21 (86%) subjects. Conclusions: Sensor measurements can be an effective way to identify and characterize infiltrations and venous stasis. Comparable to an infiltration, venous stasis may produce spurious and clinically meaningful measurement bias and possibly even scan misinterpretation. Since the quality and quantification of PET/CT studies are of clinical importance, sensor measurements acquired during the FDG uptake may prove to be a useful quality control measure to reduce infiltration rates and potentially improve patient care. Registration: Clinicaltrials.gov, Identifier: NCT03041090.

Novel Method to Detect and Characterize 18F-FDG Infiltration at the Injection Site: A Single-Institution Experience.

A novel quality control and quality assurance device provides time-activity curves that can identify and characterize PET/CT radiotracer infiltration at the injection site during the uptake phase. The purpose of this study was to compare rates of infiltration detected by the device with rates detected by physicians. We also assessed the value of using the device to improve injection results in our center. Methods: 109 subjects consented to the study. All had passive device sensors applied to their skin near the injection site and mirrored on the contralateral arm during the entire uptake period. Nuclear medicine physicians reviewed standard images for the presence of dose infiltration. Sensor-generated time-activity curves were independently examined and then compared with the physician reports. Injection data captured by the software were analyzed, and the results were provided to the technologists. Improvement measures were implemented, and rates were remeasured. Results: Physician review of the initial 40 head-to-toe field-of-view images identified 15 cases (38%) of dose infiltration (9 minor, 5 moderate, and 1 significant). Sensor time-activity curves on these 40 cases independently identified 22 cases (55%) of dose infiltration (16 minor, 5 moderate, and 1 significant). After the time-activity curve results and the contributing factor analysis were shared with technologists, injection techniques were modified and an additional 69 cases were studied. Of these, physician review identified 17 cases (25%) of infiltration (13 minor, 3 moderate, and 1 significant), a 34% decline. Sensor time-activity curves identified 4 cases (6%) of infiltration (2 minor and 2 moderate), an 89% decline. Conclusion: The device provides valuable quality control information for each subject. Time-activity curves can further characterize visible infiltration. Even when the injection site was out of the field of view, the time-activity curves could still detect and characterize infiltration. Our initial experience showed that the quality assurance information obtained from the device helped reduce the rate and severity of infiltration. The device revealed site-specific contributing factors that helped nuclear medicine physicians and technologists customize their quality improvement efforts to these site-specific issues. Reducing infiltration can improve image quality and SUV quantification, as well as the ability to minimize variability in a site's PET/CT results.

Feasibility and Reliability of Pediatric Early Warning Score in the Emergency Department.

Pediatric early warning scores in an emergency department may be used in routine patient evaluation of illness severity and resource allocation, thereby positively impacting quality and safety in pediatric care. This prospective nursing study assessed the feasibility and reliability of pediatric early warning scores in a busy, inner-city, level 1 trauma center pediatric emergency department. The pediatric early warning scores demonstrated high interrater reliability (degree of agreement among scorers) (intraclass correlation coefficient = 0.91) and intrarater reliability (multiple repetitions by a single scorer) (intraclass correlation coefficient = 0.90).

Treatment with adenosine diphosphate receptor inhibitors-longitudinal assessment of treatment patterns and events after acute coronary syndrome (TRANSLATE-ACS) study design: expanding the paradigm of longitudinal observational research.

BACKGROUND: Platelet inhibition is critical in reducing both short- and long-term atherothrombotic risks after acute myocardial infarction (MI), especially among patients managed with percutaneous coronary intervention (PCI). Currently available antiplatelet medications, including adenosine diphosphate (ADP) receptor inhibitors, have demonstrated variability in efficacy and safety in clinical trials, yet few studies have examined contemporary "real-world" approaches to platelet inhibition and associated outcomes. METHODS: TRANSLATE-ACS is a prospective observational study that will track up to 17,000 MI patients managed with PCI, from the inhospital to outpatient settings for up to 12 months postdischarge to provide a comprehensive picture of current treatment patterns and outcomes in routine clinical practice. TRANSLATE-ACS exemplifies a collaborative study design that efficiently builds upon a well-established PCI registry platform, and yet, through a systematic telephone interview follow-up process, provides important longitudinal clinical and economic follow-up capacity through 15 months after initial MI hospitalization. Furthermore, TRANSLATE-ACS incorporates a hospital-level, clustered, randomized substudy to investigate the impact of point-of-care platelet inhibition testing on subsequent patient management. Finally, TRANSLATE-ACS provides feedback through quarterly reports to participating sites on their care practices benchmarked to peer performance to support and promote longitudinal quality of cardiovascular care delivery. CONCLUSION: TRANSLATE-ACS not only addresses important clinical and scientific questions but also includes pioneering design features that will assist in the evolution of clinical registries.

Patterns of cognitive change over time and relationship to age following successful treatment of Cushing's disease.

Chronically elevated levels of cortisol have been associated with changes in cognitive functioning and brain morphology. Using Cushing's disease as a model to assess the effects of high levels of cortisol on cognitive functioning, 27 patients with Cushing's disease were examined at baseline and three successive follow-up periods up to 18 months after successful surgical treatment. At all follow-up periods, patients were administered cognitive tests as well as measures of plasma and urinary free cortisol. Structural MRIs and a depression measure were taken at baseline and one-year follow-up. Results showed that there is a specific pattern of significant cognitive and morphological improvement following successful treatment. Verbal fluency and recall showed recovery, although brief attention did not. Age of participants was a significant factor as to when recovery of function occurred; younger patients regained and sustained their improvement in cognitive functioning more quickly than older participants. Improvement in verbal recall also was associated with a decrease in cortisol levels as well as an increase in hippocampal formation volume one year after treatment. Overall, these findings suggest that at least some of the deleterious effects of prolonged hypercortisolemia on cognitive functioning are potentially reversible, up to at least 18 months post treatment.

Use of male condoms during and after randomized, controlled trial participation in Cameroon.

BACKGROUND AND OBJECTIVE: This study evaluated patterns of long-term use of male condoms among partners of 966 Cameroonian women who received eight intensive, monthly counseling sessions about condoms and sexually transmitted infection testing and treatment. METHOD: An interrupted time-series design was used with study participants reporting condom use and other covariates at enrollment, monthly for 6 months during the randomized, controlled trial, and at approximately 14 months after the trial. RESULTS: Consistent condom use began decreasing while women were still receiving monthly condom use counseling, with every month in the trial associated with an odds ratio of 0.96 (95% confidence interval [CI], 0.94-0.99) of consistent condom use and dropped substantively after the trial with a 0.39 (95% CI, 0.26-0.59) odds ratio in a logistic regression analysis. The incidence of unprotected coital acts as each month passed increased by 3% (95% CI, 1-4%) with no statistically significant change during the condom use follow-up survey as indicated in a zero-inflated Poisson regression model for unprotected coital acts. Condom use in a coital act was 0.84 (95% CI, 0.78-0.92) less likely during the follow-up survey than during the trial. CONCLUSION: Only a few women sustained consistent condom use throughout the study period and for more than 1 year after. It is important to continue documenting the impact of condom promotion in a rigorous manner and to identify content and delivery of counseling that will lead to sustained condom use beyond the intervention period.

Effect of nonoxynol-9 gel on urogenital gonorrhea and chlamydial infection: a randomized controlled trial.

CONTEXT: Nonoxynol-9 has been suggested as a vaginal microbicide to protect against common sexually transmitted infections. OBJECTIVE: To compare nonoxynol-9 gel and condom use (gel group) vs condom use alone (condom group) for the prevention of male-to-female transmission of urogenital gonococcal and chlamydial infection. DESIGN AND SETTING: Randomized controlled trial conducted at 10 community clinics and 10 pharmacies in Yaoundé, Cameroon, between October 1998 and September 2000, with 6 months of follow-up. PARTICIPANTS: High-risk population of 1251 women (excluding sex workers) being treated for or who had symptoms of sexually transmitted infections. Three were excluded from the gel group (0.5%) and 7 from the condom group (1%) because of no follow-up data. INTERVENTIONS: Nonoxynol-9 gel (100 mg) and condoms or condoms only. MAIN OUTCOME MEASURE: A positive test result for gonococcal or chlamydial infection by the ligase chain reaction assay; secondary outcome measure was a positive test result for human immunodeficiency virus (HIV). RESULTS: The rate ratio (RR) for new urogenital infections was 1.2 for the gel group vs condom group (95% confidence interval [CI], 0.9-1.6; P =.21). The gel group had 116 diagnosed gonococcal infections, chlamydial infections, or both for a rate of 43.6 per 100 person-years, and the condom group had 100 infections for a rate of 36.6 per 100 person-years. The RR for gonococcal infection in the gel group vs the condom group was 1.5 (95% CI, 1.0-2.3) and for chlamydial infection was 1.0 (95% CI, 0.7-1.4). There were 5 new cases of HIV infections in the gel group and 4 in the condom group. Three women in each group became pregnant during the study. CONCLUSION: Nonoxynol-9 gel did not protect against urogenital gonococcal or chlamydial infection.