Source of Support: None, Conflict of Interest: None
One of the physical factors affecting SPECT's images is the extremely low frequency electromagnetic fields (ELF) radiated from electrical devices. To create ELF we connected 8 serially combined solenoids to the mains supply (220 Volts, 50 Hz) with 4 amperes current flowing through them. The solenoids were moved along the vertical plane below the face of the detector to change the ELF intensity. The magnetic
flux density of the created ELF was found to be between 0.05 mT and 1.2 rnT at the center of the detector. We found that ELF had exponentially decreased the count rates of a 99mTc point source by diverting the electrons in the phototubes from their course. We deduce that ELF affects the routine quality control test results of SPECT and deteriorate the images.