Evaluation of the use of a modular detector system to collect data in real-time data to detect and assess infiltration.

2136 Objectives: valuation of the use of a modular detector system to collect data in real-time data to detect and assess infiltration Intro A modular radiation detector system has been developed by Lucerno Dynamics, LLC. The detector device was developed, and is FDA approved for use in detecting infiltrations of radioactive tracers injected for molecular studies. The current version of this device collects all data during the uptake time and then is uploaded to a server where the data can be visualized and assessed for signs of infiltration. If a severe infiltration were present, the patient would be rescheduled. The objective of this study is to test the feasibility of using this device for real time assessment of the injected dose rather than the current mechanism that allows retrospective analysis of the acquired data. Materials and Methods For this feasibility assessment, seven PET/CT patients were connected to the detector device prior to their FDG injections. Two small detectors were placed on the patients with one on the injection arm distal to the injection site, and the other placed on the opposite arm in the same area to serve as a control. During the delivery of the tracer, counts from seven time points were manually captured from the detector device: 5sec, 10sec, 20sec, 30sec, 40sec, 50sec, and 60sec post-injection. Using this data, predictions were made on whether an infiltration had occurred or not based on how rapidly the counts decreased to typical baseline values of 200-400 counts. The standard automated data collection using the device continued from the time of injection until the completion of the patient uptake time (approximately 60 minutes). The data were then uploaded to the device server to obtain the complete time activity curves. This automated system also calculates a score for each injection which provides a quantitative metric of the degree of infiltration. Manually collected data points were compared to the device-collected curves to assess if the data converged, and if so, how rapidly. Convergence rates were compared to the scoring system to determine if manual predictions were accurate, and at what minimum times could real-time assessments provide a reasonable determination of an infiltration. Results Based on manual, real-time data collection, baseline threshold values were reached within 30 seconds. From manually collected data, we predicted no infiltrations for all seven patients. When compared to the automated device assessment and scoring system, it confirmed that none of the seven patients experienced an infiltration. Conclusions An external detector device may be used to ascertain that an injection is sufficient within only a 30-45 second acquisition. Although less accurate than being able to analyze a longer and more complete set of time activity curves, severe infiltrations would take much longer to reach baseline compared to non-infiltrated injections. The standard method for using this device is to inject the entire patient dose and then assess the injection quality following the full uptake time. If severely infiltrated, the patient must be rescheduled but they still will have received the full radiation burden of the injected PET tracer. This initial analysis suggests that use of a real-time measurement technique can potentially reduce patient dose by enabling an injection of only a small amount of the patient dose to test the IV placement. If the injection site is infiltrated a new IV will be started or the patient rescheduled without having to inject the full patient dose.