Evaluation of Image Quality and Radiation Dose according to Use of the Tin Filter during CT Examination

The Tin Filter used in CT scans in medical field has the effect of reducing patient exposure without deteriorating the image quality by block in low-energy X-rays (ranging 30-50 keV) generated from CT scanners. In this study, chest low-dose CT scans were performed with the lungman phantom and various low-dose scan protocol. Then, the image quality of acquired images were evaluated by comparing the radiation dose as to the use of tin filter. The performed evaluation showed that when performing CT scans with a Tin filter installed, the exposure dose was considerably reduced by removing low energy X-rays, but SNR and CNR decreased slightly. Therefore, it is significantly considered that the use of a tin filter in CT scans will help reduce the exposure dose as well as the patient dose while maintaining image quality.