CT Image Quality and Dose Reduction Management

Abstract

Medical imaging is characterized by tremendous and undeniable benefits for patients in recent health care. Combining two imaging methodologies into a single examination, such as SPECT/ CT and PET/CT, so-called hybrid imaging, is also increased. Many factors may affect the image quality. Different CT protocols are designed to perform high-quality examination at low radiation dose. The present study is focused on the assessment of the performance of image quality for fifteen CT scanners with different scan mode (from 2slice to 320 slice) at 80, 100 and 120 kV with tube current of 50–250 mA to optimize the radiation dose. Also, the uniformity was examined as part of the quality control tests. The results showed that, the 320 slice CT scanner delivered the minimal radiation dose compared with the 16 and 64 slice CT scanners which mostly applied in Egyptian centers (governmental and private). Both 16 and 64 slice CT scanners produce acceptable image quality but with associated high absorbed dose. These results give a further support to the priority of the 320 slice CT scanner to be applied. Field uniformity measurements were adopted and the difference in the calculated values for different protocols was precisely evaluated and discussed.