双源CT超低管电压结合迭代重建技术在婴幼儿肺静脉异位引流术前评估中应用价值

目的比较双源CT(dual-source computed tomography, DSCT)超低管电压结合迭代重建技术与经胸超声心动图(trans-thoracic echocardiography, TTE)检查对婴幼儿复杂先天性心脏病肺静脉异位引流(anomalous pulmonary venous connection, APVC)的诊断准确率,探讨DSCT超低管电压结合迭代重建技术对婴幼儿APVC的诊断价值。方法拟诊APVC患儿46例,均行姑息或根治手术,术前1周内行心脏大血管DSCT造影和TTE检查。DSCT采用Flash-70kV超低管电压结合SAFIRE迭代重建技术,评价DSCT图像质量并计算扫描剂量,以手术结果为金标准,比较DSCT与TTE检查诊断APVC的准确率。结果 DSCT图像质量优25例,良19例,差2例;患儿有效辐射剂量为(0.20±0.07)mSv。46例患儿经手术证实均为完全性APVC(total APVC, TAPVC),其中心上型16例,心内型18例,心下型6例,混合型6例,共152支畸形引流肺静脉,合并其他畸形82处。DSCT发现146支畸形引流肺静脉,诊断准确率为96.1%(146/152);发现其他合并畸形78处,诊断准确率为95.1%(78/82),除2例混合型TAPVC误诊为单纯心上型外,其余分型诊断正确。TTE检查发现130支畸形引流肺静脉,诊断准确率为85.5%(130/152);发现其他合并畸形80处,诊断准确率为97.6%(80/82),漏诊1例合并多种复杂畸形的TAPVC患儿,3例心下型TAPVC不能明确分型,6例混合型TAPVC均误诊为单纯型TAPVC,其余分型诊断正确。DSCT对异常引流肺静脉的诊断准确率(96.1%)及在心下型、混合型TAPVC的分型诊断准确率(100.0%、66.7%)高于TTE(85.5%、50.0%、0)(P<0.05)。结论与TTE检查相比,DSCT Flash-70kV超低管电压结合SFIRE迭代重建技术对婴幼儿TAPVC的诊断准确率高,具有较高诊断价值。

Application of dual-source CT ultra-low tube voltage technique combined with iterative reconstruction in assessing infant anomalous pulmonary venous connection

Objective To compare the accuracies of dual-source computed tomography(DSCT) with ultra-low tube voltage SAFIRE iterative reconstruction algorithm technology and trans-thoracic echocardiography(TTE) in the diagnosis of infants anomalous pulmonary venous connection(APVC), and to investigate the value of DSCT with ultra-low tube voltage SAFIRE iterative reconstruction algorithm technology to the diagnosis of APVC in infants. Methods Forty-six infants with suspected APVC received palliative or radical surgery. DSCT and TTE were performed one week before surgery. DSCT adopted Flash-70 kV voltage tube technique combination SAFIRE iterative reconstruction algorithm technology to evaluate DSCT image quality and calculate radiation dose. Taking the surgical outcome as gold standard, the accuracies of DSCT and TTE on APVC were compared. Results The image quality of DSCT was excellent in 25 patients, good in 19, and poor in 2. The effective radiation dose was(0.20±0.07) mSv. All these 46 cases were confirmed total APVC(TAPVC) by surgery, including 16 cases of supracardiac type, 18 cases of intracardiac type, 6 cases of infracardiac type and 6 cases of mixed type. There were 152 total anomalous drainage pulmonary veins and 82 malformations. DSCT found 146 anomalous drainage pulmonary veins, with a diagnostic rate of 96.1%(146/152), and 78 other concomitant abnormalities, with a diagnostic rate of 95.1%(78/82);all diagnoses were correct except 2 cases of mixed TAPVC misdiagnosed as pure intracardiac type. TTE found 130 malformed drainage pulmonary veins, with a diagnosis rate of 85.5%(130/152), and 80 other malformations, with a diagnosis rate of 97.6%(80/82);one child with multiple complex malformations of TAPVC was missed diagnosed, 3 cases of subcardiac TAPVC were not clearly classified, 6 cases of mixed TAPVC were misdiagnosed as simple TAPVC, and the rest diagnoses were correct. The diagnostic rate of DSCT for the number of anomalous drainage pulmonary veins(96.1%)and the classification accuracies of infracardiac and mixed TAPVC(100.0%,66.7%)were higher than those of TTE(85.5%,50.0%,0)(P<0.05).Conclusion Compared with TTE,DSCT Flash-70 kV voltage tube technique combined with SAFIRE iterative reconstruction algorithm technology has higher diagnostic accuracy and diagnostic value.