小儿动脉韧带钙化——一个正常的CT征象

Calcification of the Ligamentum Arteriosum in Children:a Normal Finding on CT

目的:胸部CT平扫分析小儿动脉韧带钙化(CLA)的形态特征、发生率及其年龄分布趋势,提高对该征象的正确认识。方法:回顾性分析1200例小儿胸部CT平扫资料,按年龄分为婴儿组、幼儿组、学龄前组、学龄组和青春组五组,观察CLA形态特征,统计各年龄组CLA发生率。结果:小儿CLA常表现为点状及条状及曲线状钙化,CLA发生率19.42%(233/1200),其中幼儿组最高26.46%(59/223)。CLA最小发生年龄为2个月。本组动脉韧带钙化CT值在82～301HU,平均(130.49±47.25)HU;Spearman相关性分析,小儿CLA的CT值(密度)与年龄没有相关性(r=0.007,P=0.912)。各组两两比较发现仅婴儿组与幼儿组CLA发生率差别有统计学意义(χ2=11.174,P=0.001<0.005)。结论:小儿动脉韧带钙化发生与年龄增长没有相关性,正确认识小儿CLA的CT特征及其发生情况,可减少误诊。

Objective：To describe the pattern, frequency and age distribution of calcification of ligamentum arterio- sum （CLA） on unenhanced chest CT in children. Methods： 1200 subjects were retrospectively reviewed on unenhanced chest CT materials. Mean patient age was （4.77%4.32） years,ranging from 1 day-18 years with 463 girls （39%） and 737 boys （61 %）. These subjects were divided into five groups （infants, toddlers, preschoolers, school children and adolescents）. The pattern,size and CT value of CLA were observed and measured on CT. Results：Of 1200 patients,233 （19, 42%） cases pre- sented CLA （female-. 85 （18. 36%） ; male; 148 （20. 08%）. The frequencies of CLA in the five groups were 14. 58%, 26.46 %, 23.02 %, 16.38 % and 17.52 %, respectively. The difference of total frequency among the five groups was signifi- cant （X2= 15. 574, P〈 O. 004-0.05）. No significant difference was found between each two groups except for the groups between infant and toddlers （3（2 =11. 174,P=0. 001）. The CT value of CLA range from 82-301HU and mean CT value was （130.49dz47.25）HU. Spearman correlation analysis showed no significant correlation （r= 0. 007, P=0. 912） between the CT value and age among 233 cases of CLA. The minimum age of calcification appearance was 2 months,63 patients （in- cluding 8 neonates） were younger than 2 months,they did not show CLA. The pattern of calcification was characterized as point-like or punctate （88 cases）,strip-like （84 cases）,curvilinear （46 cases）,funnel-like （12 cases） and nodule-like （3 ca- ses） on axial CT images. Conclusion： CLA is a common finding on unenhanced chest CT in children, which should not be confused with other mediastinal pathologic calcifications. The frequency of CLA is poorly correlated with the age in child- hood. Knowing the characteristic pattern and anatomical position of CLA may be useful for improving clinical diagnosis confidence.