The Lucerno Solution
The Lara® System
The Lucerno Lara System is currently listed with the FDA and uses sensors on the patient’s skin to measure the radiation emitted from the areas of interest beneath the sensors.
Prior to the injection, sensors are placed on the patient’s arms, using atraumatic adhesive pads. One sensor captures activity from the radiotracer at the injection site and the second sensor from the other arm, which acts as a control. Lara provides a real time display of injection quality and after a portion of the uptake period, the sensors can be removed and recorded data can be uploaded to the Lucerno Web Application, Ellexa®. Within seconds, Lucerno provides a report.
Since our sensors record the level of radiotracer in the areas of interest during and after the injection, Lucerno provides clinicians with evidence of the presence of radiotracer in the injection area during the uptake process. This information helps clinicians to evaluate the quality of the injection process to determine if an infiltration has occurred. With this information clinicians can assess the amount of unintentional radiation delivered to the patient’s arm tissue and can assess the level of confidence that can be placed in the images used in patient management decision making.
The system is agnostic to the imaging field of view used in each center, the experience of the technologists, the quality of the patient’s injection vein, or if an auto-injector is used.
Lara is easy to use, requires no additional radiotracer, and just adds twenty seconds to the patient experience and one to two minutes to the technologist’s process, but provides the quality control needed to ensure nuclear-medicine scan has not been compromised by an infiltration.
Quality control of injections is especially important in everyday use of PET scans and vital for clinical studies that rely on PET scans as part of the protocol.
The Lucerno graph below shows an ideal injection. It is ideal because the injection arm sensor curve (black line) and the reference arm sensor curve (red line) reach equilibrium within seconds. All nuclear medicine injections should look like this one.
The black line in the Lucerno graph (below left) shows a dramatically high level of radioactivity detected by the injection arm sensor. The red line shows the level of activity from the reference arm sensor. The review of the time-activity curve prior to the patient being imaged, alerted the technologist to ensure the injection site was in the imaging field of view. As a result, this infiltration was confirmed to be significant by the director of the PET center after measuring the remaining activity near the injection site at time of imaging.
A static nuclear medicine image is not enough
From the time-activity curve below, it would appear that by the time of imaging the injection sensor and reference sensor outputs would be very similar. In this situation, the injection site would appear to look normal or at worst have some small trace of radiotracer near the injection site. The static image would not accurately reflect the quality of the injection. By reviewing the time-activity curve, the physician would know that a patient did not receive the entire bolus injection as expected.
While not an infiltration, a prolonged venous stasis may affect the delivery of the radiopharmaceutical. A static image taken of the injection site can lead clinicians to believe the radiopharmaceutical was ideally administered, when in fact, a prolonged venous stasis may have delayed the actual delivery of the radiopharmaceutical. The Lara® System can alert clinicians to the fact that a radiopharmaceutical was not delivered as intended, even though the static image of the injection site suggests the radiopharmaceutical was administered ideally.
Dynamically acquired images (bottom row) taken at various times (blue arrows) during uptake, static image (upper right), and black TAC (top curve) from injection arm sensor all reflect the complete resolution of a prolonged venous stasis. Red TAC reflects uptake captured by reference arm sensor on the non-injection arm during the uptake period. Blue TAC reflects liver uptake. Proximity to injection arm sensor and nature of the liver uptake played some role in injection arm sensor TAC interpretation. Patient was positioned on PET imaging table to ensure the injection site would be located near the caudal edge of the PET imaging bed. Red arrows on dynamic image acquisition frames and static image indicate approximate injection site (right antecubital fossa).
Watch the video to see how a prolonged venous stasis resolves during the uptake period.
In this case below the injection site was out of the imaging field of view, but the patient experienced a significant infiltration that was identified by Lara and confirmed when the patient returned five days later for re-scan. Note the quality of the images taken after the infiltrated injection versus the images taken after an ideal injection. Quantification of these metastatic lesions were understated between 30-70% due to the infiltration.
Lucerno can provide QA/QC for radiopharmaceutical* injections
The Lara System is intended for use in nuclear medicine to provide quality control for radiotracer injections. With the Lara System, clinicians can know, before the uptake period is over, whether the injection was ideal or not.
While it is important to provide quality control for each individual radiotracer injection, the Lara System can provide quality assurance for a nuclear medicine center’s injection process. By using Lara with Lucerno’s proprietary Ellexa® software, centers can identify factors associated with infiltrations, make appropriate adjustments, and improve quality. Through periodic reviews of these associated factors and process improvements, centers can improve patient safety, drive their overall infiltration rate down, and drive their quality indices up.
*Radiopharmaceuticals must include a gamma emission.