Optimization of mandibular CT scanning / 中华放射医学与防护杂志

ABSTRACT

Objective To Optimize the mandibular CT scanning methods with changing the scanning position,to reduce the radiation dosage.Methods Totally 50 consecutive patients with mandibular CT examination were enrolled in the study and divided into position-optimized group and routine group (n =25,respectively) randomly.The image quality,volume CT-dose index (CTDIvol),scanning length,and dose length product (DLP) were compared.Results There was no significant difference in subjective image quality and CTDIvol between two groups.But the scanning length and DLP in positionoptimized group were significantly reduced by about 20 ％ (t =4.986,P ＜ 0.05) and 16％ (t =3.682,P ＜0.05) compared with routine group.The lens were out of scanning field with the position-optimized protocol.Conclusions The scanning length would be efficiently reduced and the lens avoided with the position-optimized protocol,which would subsequently reduce the effective radiation dose.