In the paper,we study the strong uniform consistency for the kernal estimates of random window w■th of density function and its derivatives under the condition that the sequence{X_n}of the ■ are the identically Φ-m...In the paper,we study the strong uniform consistency for the kernal estimates of random window w■th of density function and its derivatives under the condition that the sequence{X_n}of the ■ are the identically Φ-mixing random variabks.展开更多
目的:探讨CT血管造影(CTangiography,CTA)后处理技术容积重建(volumerendering,VR)中阈值、最大密度投影(maximum intensity projection,MIP)中窗宽及窗位、视野(Field of view,FOV)对血管管径测量的影响及相关关系。方法:建立9个不同...目的:探讨CT血管造影(CTangiography,CTA)后处理技术容积重建(volumerendering,VR)中阈值、最大密度投影(maximum intensity projection,MIP)中窗宽及窗位、视野(Field of view,FOV)对血管管径测量的影响及相关关系。方法:建立9个不同密度的血管模型,使用不同的FOV、阈值(VR)、窗宽(MIP)测量不同密度血管模型管径,分析标准阈值、窗宽与血管模型管径的关系,并与CT值进行相关性分析。统计临床脑血管CTA MIP重建病例30例的窗宽及窗位,与实验结果进行比较。结果:VR重建,阈值和血管模型管径呈明显负相关(r=-0.847,P=0.000);MIP重建,窗宽和血管模型管径呈明显正相关(r=0.983,P=0.000);FOV和血管模型管径无相关性(r=-0.042,P=0.381)。临床脑血管CTAMIP重建窗宽明显增宽,夸大了血管真实管径。结论:CTA血管管径测量的准确性受VR重建阈值、MIP重建窗宽窗位的影响,根据血管内对比剂密度对这些参数进行调整,保证测量血管管径的可靠性和准确性。展开更多
基金supported by Natural Science Foun■ion of Henan P■visial Commission of Bdusation
文摘In the paper,we study the strong uniform consistency for the kernal estimates of random window w■th of density function and its derivatives under the condition that the sequence{X_n}of the ■ are the identically Φ-mixing random variabks.
