目的 讨论CT在检查上气道时 应用管电流调制技术以减少辐射剂量的 可行性。方法 选取2014年3月到2015年 2月间于我院住院治疗的阻塞性睡眠呼 吸暂停低通气综合征患者共60例，采用 随机数字表法分为3组，每组20例，均 行上呼吸道CT检查。常规组：管电流 为250mA；Doseright组：管电流选取 系统推荐剂量；Z-DOM组：管电流在人 体Z轴方向自动调节。前两组管电流始 终恒定，Z-DOM组随扫描变化；计算噪 声比(CNR)，正中矢状面所成像质量使 用5分法进行评价。对3组剂量长度乘积 (DLP)、辐射剂量指标CT剂量指数(CTDI) 以及主观评价指标行统计学分析。结 果 三组在辐射剂量方面具有统计学意义 (P＜0.05),Doseright组较常规组高出 15%，Z-DOM组为Doseright组的20%,是常 规组的25%；三组CNR值比较不具备统计 学意义(P＞0.05)；主观评价比较差异具 有统计学意义(P＜0.05)，两两比较，常 规组与Doseright组比较不具有统计学意 义(P＜0.05)，Z-DOM组比其他两组比较 均具有统计学意义。结论 将Z-DOM技术 应用于上气道CT检查中，可大幅度降低 辐射剂量。

Objective To discuss the feasibility to reduce the dose of radiation in CT examination of upper airway by CT current modulation technique. Methods 60 patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) admitted in our hospital from March 2014 and February 2015 were selected as study object, which were randomly divided into three groups, 20 patients in each group, all the patients underwent upper airway CT examination. Conventional Group: tube current of 250mA, Doseright group: tube current used recommended dose from selection system, Z-DOM group: Tube current automatically adjusted in the Z-axis direction of the human body, the tube current were constant in the former groups, the tube current were changed with the scan in Z-DOM group, calculated noise ratio (CNR), the median sagittal image quality used 5 points methods for evaluation (DLP), CT dose index (CTDI) and subjective evaluation index were analyzed statistically. Results There were statistically significant differences in radiation dose among the three groups (P＜0.05), doseright group 15% higher than the conventional group, the Z-DOM group was 20% of the doseright group, 25% of the conventional group, the CNR values of the three groups were not statistically significant (P＞0.05). Subjective evaluation of the difference was statistically significant (P ＜0.05),comparison by two pairs, there was no statistically significant difference between the conventional group and the doseright group (P＜0.05),compared with the other two groups, the Z-DOM group was statistically significant. Conclusion The Z-DOM technology in the upper airway CT examination, can significantly reduce the radiation dose.