NEMA NU 2-2000 performance measurements on an ADAC MCD camera

The clinically oriented NEMA-NU2 performance standards have been performed on an ADAC MCD dual head camera. At 1 cm radius the transverse resolution FWHM (FWTM) was measured to be 5.2 (10.0) mm and the axial was 5.0 (10.6) mm. At 10 cm radius the transverse radial resolution was 4.7 (7.4) mm and the transverse tangential was 8.5 (20.9) mm. The axial resolution was 14.0 (41.1) mm. The peak true count rate was 4365 counts/sec at a concentration of 4.3 kBq/ml. The peak noise equivalent count rate (NECR) was 1617 count/sec at 2.9 kBq/ml. The system scatter fraction was 48%. The maximum relative count rate error observed at the NECR peak was -42%. The sensitivity was 1014 cts/sec/MBq in the centre and 867 cts/sec/MBq at an offset of 10 cm. The contrast for the hot spheres ranged from 18.5 (11.6)% to 11.6 (7.9)% for the contrast ratio of 8:1 (4:1). For the cold spheres it ranged from 41% to 25% with an overall background variability of 7%. The residual error in scatter and attenuation correction was approximately 50%. All measurements were performed at the maximum allowed crystal-to-crystal distance of 810 mm.