婴幼儿支气管异物CT扫描方案的优化

Optimization of CT scanning program for infants with bronchial foreign body

目的通过调整CT扫描方案,探讨降低诊断婴幼儿支气管异物CT检查辐射剂量的可行性。方法收集拟诊为支气管异物的患儿62例,按就诊顺序分别采用CARE Dose 4D常规CT扫描和新型CT扫描方案进行扫描。常规CT扫描方案先行定位像扫描确定扫描范围,后行螺旋扫描,管电压为100kV,有效管电流为39～52mAs;新型CT扫描方案以激光定位扫描范围,管电压为80kV,有效管电流设为[体质量(kg)+20]mAs。比较两种扫描方案的有效辐射剂量、图像质量以及诊断准确率。结果新型CT扫描方案有效辐射剂量低于常规扫描(P<0.05);新型扫描方案的图像诊断满意度、空间分辨力及伪影水平评分略低于常规扫描,但差异无统计学意义(P均>0.05);常规和新型CT扫描方案的诊断准确率分别为96.77%(30/31)和93.55%(29/31),差异无统计学意义(P>0.05)。结论新型CT扫描方案可明显降低辐射剂量,图像质量能够满足婴幼儿支气管异物的诊断要求,具备一定临床应用价值。

Objective To explore the feasibility of reducing radiation dose through adjustment of the scanning program in CT scanning for diagnosis of bronchial foreign in infants.Methods Sixty-two infants with suspected bronchial foreign body underwent CT scanning of CARE Dose 4D routine and new program according to the visiting sequence,respectively.In routine scanning,positioning imaging was carried on,followed by spiral scanning with tube voltage of 100 kV and effective mAs（eff mAs） of 39—52.In new program scanning,laser was used for location instead of positioning imaging,the voltage was 80 kV,and eff mAs was defined as（weight ＋20）.The effective radiation dosage,quality of image and diagnostic accuracy of the two scanning programs were compared.Results The effective dose in CT scanning of new program scanning was significantly lower than that in routine program scanning（P0.05）.The scoring of diagnostic satisfaction degree,resolution and artifacts in new program scanning were lower than routing CT scan,but the difference was not statistical（all P0.05）.The diagnostic accuracy of routing and new program CT scanning was 96.77%（30/31） and 93.55%（29/31）,respectively（all P0.05）.Conclusion The radiation dose of CT scanning can be significantly decreased using new scanning program with satisfactory quality of image meeting the diagnostic demand,which has certain clinical application value.