低剂量头颅CT检查在高原山地藏区武警新兵体检中的应用价值

Application value of low dose head CT scan in physical examination of the Armed Police Force new recruits in Tibetan mountainous area

目的探讨低剂量头颅CT检查在高原山地藏区武警新兵体检中的应用价值。方法2013-2015年3年间，在新兵体检中随机抽取152名临床医生建议行头颅CT检查的新兵，行常规头颅CT和低剂量（120mAs）头颅cT扫描，每次扫描完成记录其CT剂量容积（CTDIvol）和剂量长度乘积（DLP）。再在此152人中随机抽取20人，对比其常规组及低剂量组图像，对图像质量进行评分。最后由两名高年资放射科医师对152人图像进行双盲诊断。比较常规组与低剂量组的CTDIvol、DLP，对两组图像质量得分和阳性检出率统计分析。结果低剂量组扫描CTDIvol均数加减标准差为（22．05±1．56）mGy，是常规组[（45．04±1．12）mGy]的48．9％。低剂量组的DLP均数为（255．26±26．39）mGy．cm，为常规组[（524．42±40．13）mGy．cm]的49．4％低剂量组图像质量得分（38．53±2．12），显著低于常规组[（42．35±2．13），t=6．289，P〈0．01]。常规组与低剂量组两组检出率差异无统计学意义意义。结论高原山地藏区新兵体检工作中行低剂量头颅CT是可行的，有价值的方法。

Objective To discuss the application value of low dose head CT scan in physical examination of the Armed Police Force new recruits from Tibetan mountainous area. Methods During the 3 times of physical examination 2013 to 2015, 152 new recruits who needed head CT scan examination underwent head scan with both routine dose and low dose respectively. The CT dose index volume （CTDIvol） and dose-length volume product （DLP） of each scanning waere recorded. Twenty cases were randomly selected from theses 152 recruits to evaluate the quality of scan. Numbers of cases of different intracranial diseases were compared between these 2 groups. Results The CTDIvol level of the low dose scan group was （22.05± 1.56） mGy, being 48.9% of that of the rountine dose group [（45.04± 1.12） mGy]. The DLP level of the low dose scan group was （255.26±26.39） mGy.cm, being 49.4% of that of the routine dose group [（524.42± 40.13） mGy.Cm]. The image quality score of the low dose group was （38.53±2.12）, significantly lower than that of the routine dose group [（42.35 ±2.13）, t=6.289 P〈0.01]. There were not significant differences in the detection rates of different intraeranial diseasesa between these 2 groups. Conclusion It is feasible and valuable to use the low dose head CT scan in physical examination of the Armed Police Force new recruits from Tibetan mountainous area.