优化触发阈值CTA对急性蛛网膜下腔出血的诊断研究

Study on the optimization of minimum excited threshold CTA on the diagnosis of brain with SAH

目的探讨合理的扫描触发阈值,获得满意的颅内动脉图像,以提高疾病检出率。方法将100例患者分为3组行16排螺旋CT颅脑CTA检查(触发阈值分别为110、130、150 Hu),测量右侧颈内动脉C3段,右侧大脑前、中、后动脉中段及直窦CT值,对比3组患者阈值的动静脉CT值差异,并进行主观影像质量评价。结果 3组患者动脉平均CT值与直窦CT值差值差异有统计学意义(P<0.05),主观影像质量评价差异有统计学意义(P<0.05)。结论应用16层螺旋CT行颅脑CTA,在主动脉弓降主动脉侧触发扫描并以130 HU为扫描触发阈值,能够得到满意的颅内动脉图像。

Objective To improve the accuracy of diagnosis on early stage of brain with SAH and achieve the ideal intracranial arterial images,the optimization minimum excited threshold of intracranial reasonable CT was studied. Methods 100 patients were divided into three groups and underwent brain CTA analysis using 16 multi- detector spirals CT（ designed three excited threshold CTA values： 110 HU,130HU,150HU）. C3 and RACA of right internal carotid artery,the right middle cerebral artery,and the straight sinus in the right posterior cerebral artery were measured. The artery CT thresholds and the image quality parameters among the three groups were measured and compared subjectively. Results The artery CT thresholds and the straight sinus CT were significantly different among these three groups by statistical analysis（ P 〈 0. 05）,and the difference were significant with higher image quality subjectivity（ P 〈0. 05）. Conclusion The ideal image quality of brain CTA can be obtained if the scanning is triggered from the aortic arch,the threshold value is set at 130 Hu by using16 multi- detector spiral CT.