Popota, Foteini D.,1980-Aguiar, PabloHerance Camacho, José RaulPareto, DeborahRojas, SantiagoRos, DomènecPavía Segura, JavierGispert López, Juan Domingo2015-09-232015-09-232012Popota, F.D.; Aguiar, P.; Herance, J.R.; Pareto, D.; Rojas, S.; Ros, D. et al. Comparison of the Performance Evaluation of the MicroPET R4 Scanner According to NEMA Standards NU 4-2008 and NU 2-2001. IEEE Trans Nuc Science. 2012;59(5):1879-86. DOI: 10.1109/TNS.2012.22087600018-9499http://hdl.handle.net/10230/24756The purpose of this work was to evaluate the performance of the microPET R4 system for rodents according to the NU 4-2008 standards of the National Electrical Manufacturers Association (NEMA) for small-animal positron emission tomography (PET) systems and to compare it against its previous evaluation according the adapted clinical NEMA NU 2-2001. The performance parameters evaluated here were spatial resolution, sensitivity, scatter fraction, counting rates for rat- and mouse-sized phantoms, and image quality. Spatial resolution and sensitivity were measured with a 22Na point source, while scatter fraction and count rate performance were determined using a mouse and rat phantoms with an 18F line source. The image quality of the system was assessed using the NEMA image quality phantom. Assessment of attenuation correction was performed using γ-ray transmission and computed tomography (CT)-based attenuation correction methods. At the center of the field of view, a spatial resolution of 2.12 mm at full width at half maximum (FWHM) (radial), 2.66 mm FWHM (tangential), and 2.23 mm FWHM (axial) was measured. The absolute sensitivity was found to be 1.9% at the center of the scanner. Scatter fraction for mouse-sized phantoms was 8.5 %, and the peak count rate was 311 kcps at 153.5 MBq. The rat scatter fraction was 22%, and the peak count rate was 117 kcps at 123.24 MBq. Image uniformity showed better results with 2-D filtered back projection (FBP), while an overestimation of the recovery coefficients was observed when using 2-D and 3-D OSEM MAP reconstruction algorithm. All measurements were made for an energy window of 350-650 keV and a coincidence window of 6 ns. Histogramming and reconstruction parameters were used according to the manufacturer's recommendations. The microPET R4 scanner was fully characterized according to the NEMA NU 4-2008 standards. Our results diverge considerably from those previously reported with an adapted version- of the NEMA NU 2-2001 clinical standards. These discrepancies can be attributed to the modifications in NEMA methodology, thereby highlighting the relevance of specific small-animal standards for the performance evaluation of PET systems.application/pdfeng© 2012 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. The final published article can be found at http://dx.doi.org/10.1109/TNS.2012.2208760National Electrical Manufacturers AssociationEspaiRates (Animals de laboratori)info:eu-repo/semantics/articlehttp://dx.doi.org/10.1109/TNS.2012.2208760info:eu-repo/semantics/openAccess