Comparative Analysis of Quality Control Tests of Traditional PET/CT scanner vs Total Body PET/CT Scanner

3067 Objectives: A thorough Quality Assurance program consists of tests for quality control (QC) and calibration defined by the manufacturer, along with additional tests to be periodically completed based on National Electrical Manufacturer Association (NEMA) to document system performance. Many of the QC and calibration protocols use phantoms that are manufacturer, and often scanner, specific. For PET/CT, these tests should be conducted, recorded, and monitored consistently, so that any drift or change in the system can be corrected prior to having any effect on the clinical diagnosis of patients. The objective of this work is to describe the QC program developed at UC Davis for the uExplorer total-body PET/CT system and to compare that with other QC programs implemented for traditional PET/CT scanners having an axial length ~15 cm.\n Methods: The quality control tests of a GE DISCOVERY 690 PET/CT scanner with an axial FOV of 157 mm was compared to a uExplorer PET/CT scanner with an axial FOV of 1940 mm. Daily, Weekly, Quarterly, Semi-Annual and Annual Quality Control tests were performed using NEMA and manufacturer recommended standards. QC tests including Sensitivity, System Spatial Resolution, ACR Image Quality, and Normalization calibration were evaluated and compared, based on completion time, methodology used, and protocol.\n Results: Time of completion and methodology were similar between the uExplorer and the GE Discovery for Daily and Weekly QC tests. Sensitivity, System Spatial Resolution, ACR Image Quality and Normalization calibration with uExplorer require testing at multiple locations along the axial FOV due to the extended length, which increases the overall time required for scanning, though many of the testing methodologies remains similar. When compared to a traditional PET scanner, calibration methods for uExplorer are more challenging due to the significantly elongated phantom geometries, which can be difficult to fill and are cumbersome to transport and position. Discussion: With the addition of a newly manufactured Total Body PET/CT scanner, consideration in the length of time and periodicity of recommended tests should be evaluated in order to organize a thorough Quality Assurance Program. A list of tests that are to be done can be scheduled accordingly with respect to clinical workflow.\n Conclusions: The extended Axial FOV of a Total Body PET/CT scanner does not increase scan time of daily and weekly QC and are comparable to a traditional PET/CT scanner. Calibrations prove to be more challenging due to having to test the full length of the extended FOV. However, due to the more modern design of the uExplorer scanner compared to the DISCOVERY 690, the manufacturer recommends less frequent calibrations.