Assessment of coronary artery by prospective ECG-triggered 256 multi-slice CT on children with congenital heart diseases / 中华放射医学与防护杂志

ABSTRACT

Objective To investigate the image quality and radiation dosage of the prospective ECG-triggered 256 multi-slice computer tomography (MSCT) angiography in accessing coronary artery (CA) on children.Methods Coronary arteries of ninety-three children were evaluated using prospective ECG-triggered 256-MSCT with the same system setting.Seventy-four patients had the heart rate records and a four-point scoring system was applied to study the capability of MSCT in detecting CA.The signal,noise and contrast-to-noise ratio (CNR) were analyzed to investigate the association of image quality with age (n =74).Then volumetric CT dose index (CTDIvol),dose-length product (DLP) and effective dose (E) were utilized to study the association of radiation dosage with age (n =93).Results On 74 patients with heart records,the detection rate for original,proximal,middle,distal and all 11 segments of CA was 100％,97％,92％,78％ and 91％,respectively.No influence of age was found on their detection (all P＞0.05).E of group A,B,C and D were 1.8,1.3,0.8 and 0.7 mSv,respectively.A strong negative correlation was found between E and age (r =-0.803,P ＜ 0.01).Higher DLP was found on elder patients,though no correlation was found between ages vs.DLP(r =0.124,P ＞ 0.05).No correlation was found between noise vs.age (r =0.041,P ＞ 0.05).Significantly larger signals,CNR and E(t =3.386,2.073,3.825,P ＜ 0.05) were found on younger patients (age ＜ 3 years).Conclusions Prospective ECG-triggered 256-MSCT has considerable performance for the evaluation of coronary arteries on children.However,children under the age of 3 are not recommended for this examinary,but for examination on children ≥ 8-year old,the tube current could be further needed.