摘要
目的探讨脑动、静脉增强曲线最高值及增强峰值对 CT 灌注参数及其图像信噪比(SNR)的影响。方法 17例患者行多层螺旋 CT(MSCT)脑灌注扫描后经灌注软件后处理,每一病例处理6次,生成不同的动、静脉增强曲线。记录每次生成的动、静脉曲线最高值和增强峰值及同侧脑白质、灰质感兴趣区(ROI)内灌注参数,即脑血流量(CBF)、脑血容量(cBV)、平均通过时间(MTT)和表面通透性(PS)的平均值,并由参数平均值除以相应标准差,计算相应 SNR。应用 SPSS 10.0软件包对数据进行 Pearson 相关分析及配对 t 检验。结果 (1)白质平均 SNR_(CBF)为1.61±0.36,灰质为3.01±1.14;白质平均 SNR_(CBV)为2.47±0.66,灰质为3.68±1.12;白质平均 SNR_(MTT)为1.54±0.33,灰质为2.53±0.84;白质平均 SNR_(ps)为0.50±0.16,灰质为0.62±0.21。动、静脉曲线最高值及增强峰值与白质和灰质平均 SNR_(CBF)、SNR(CBV) 及 SNR_(MTT) 值(r 值介于0.332～0.922,P 值均<0.01),以及静脉曲线最高值与白质平均 SNR_(ps)值(r=0.256,P<0.05)之间呈正相关;动脉曲线最高值、增强峰值及静脉增强峰值与白质和灰质平均 SNR_(ps)值,以及静脉曲线最高值与灰质平均 SNR_(ps)值之间无明显相关性(r 值介于-0.058～0.210,P 值均>0.05)。(2)高、低静脉组之间平均 CBF、CBV 及 PS 值的差异均有统计学意义(t 值介于3.830～5.337,P 值均<0.01);高、低静脉组之间平均 MTF 值(白质 t=-0.277,灰质 t=0.329,P 值均>0.05)及高、低动脉组之间所有灌注参数平均值( t 值介于-0.987～1.197,P 值均>0.05)差异均无统计学意义。结论动、静脉曲线最高值及增强峰值对脑CT 灌注图像 SNR 的影响具有统计学意义;静脉曲线最高值及增强峰值对灌注参数平均值的影响具有统计学意义;图像后处理时应该将动、静脉曲线调高以提高灌注参数的准确性及图像 SNR。
Objective To explore the influence of the maximal value and peak enhancement value of arterial and venous enhancement curve on CT perfusion parameters and signal-to-noise ratio （SNR）. Methods Seventeen patients underwent brain CT perfusion scanning. All row data were analyzed with perfusion software for 6 times, and get different arterial and venous enhancement curves for each patient. The maximal values and peak enhancement values of each arterial and venous enhancement curves, as well as mean perfusion parameters including cerebral blood flow （CBF） ,cerebral blood volume （CBV） ,mean transit time （MTF）, permeability surface area product （PS）, and their standard deviations （SD） in homolateral white and gray matter were measured and recorded. SNR was calculated by dividing the mean perfusion parameter value by its SD. Pearson correlation analysis and two-tailed paired Student t test were used for statistics. Results The maximal values and peak enhancement values of arterial and venous curves were correlated with mean SNRcbf, SNRcbv and SNRmtt in both white matter and gray matters （ r value range： 0.332-0.922, P 〈0.01）. The maximal value of venous curve was also correlated with SNRps in white matter （ r=0.256, P 〈0.05）. No correlation was found either between SNRps （ in both white matter and gray matters ） and arterial peak enhancement values, the maximal values and venous peak enhancement values, or between SNRps （in gray matter）and the maximal values of venous curve（ r value range： -0.058-0.210,P 〉0.05）. （2） Mean CBF, CBV and PS values in the group with low venous peak enhancement values were significantly different from the group with high venous peak enhancement values in both white and gray matters （t value range： 3.830-5.337,P 〈 0.01 ）, but no significant difference in mean MTF values. There were no significant differences for all mean perfusion parameter values in both the low and high arterial peak enhancement values groups （ t value range
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2007年第7期687-691,共5页
Chinese Journal of Radiology
关键词
脑血管循环
体层摄影术
X线计算机
灌注
局部
因素分析
统计学
Cerebrovascular circulation
Tomography, X-ray computed
Perfusion, regional
Factor analysis, statistical
