椎动脉增强磁共振血管造影少量对比剂预注射试验分析

目的验证能否通过年龄、体重、心率等推测对比剂峰值时间,评价少量对比剂预注射试验的应用价值.方法搜集55例椎动脉增强MR血管造影（CEMRA）前少量对比剂预注射试验的有关数据,包括年龄、体重、心率、到达时间、峰值时间、持续时间、峰值信号等,所得数据利用SPSS软件进行直线相关和回归分析.结果年龄（55例,平均年龄62岁,中位年龄59岁）、体重（55例,平均体重63kg）、心率（40例,平均心率73次/min）与对比剂峰值时间（55例,平均峰值时间17.5 s）之间的相关度在α=0.05水平差异没有统计学意义（相关系数r分别为0.231、0.118、-0.046,t值分别为1.728、0.865、-0.284,P值分别为0.090、0.392、0.776）.峰值时间与峰值信号（55例,平均峰值信号472）有显著的负相关（r=-0.322,t=2.56,P=0.016）而与持续时间（49例,平均持续时间10.35 s）有显著的正相关（r=0.658,t=5.99,P=0.000）,峰值信号与体重呈显著负相关（r=-0.356,t=2.77,P=0.008）.峰值信号与峰值时间、体重的直线回归分析结果中,其标准化回归系数b分别为-0.284和-0.322,t值分别为-2.285和-2.590,P值分别为0.026和0.012.结论通过年龄、体重、心率推测对比剂峰值时间不可靠;通过少量对比剂预注射试验,能获得合适的正式扫描延迟时间,并能对正式扫描时对比剂注射流率作及时调整.

A study on pre-injection test with mini-dose contrast medium in contrast-enhanced magnetic resonance angiography of vertebral artery

Objective To evaluate mini-dose pre-injection test in the use of contrast-enhanced magnetic resonance angiography (CEMRA), and to inspect the possibility of contrast medium peak-time prediction by age, body weight and heart rate.Methods The data from mini-dose pre-injection test of contrast medium before vertebral artery CEMRA were retrospectively reviewed in 55 patients. The linear correlation and regression of the data including age, body weight, heart rate, and the reaching-time, peak-value-time, duration and peak-value-signal of contrast medium was performed by using SPSS software.Results The age (n=55, =62 years old, M=59 years old), body weight (n=55, = 63 kg), heart rate (n=40, =73 beats per minute), peak-value-time (n=55,=17.5 seconds), peak signal intensity (n=55,=472), and duration of contrast (n=49,=10.35 seconds)were analyzed. No statistically significant correlation existed between peak-value-time of contrast medium and the age (r=0.231, t=1.728, P=0.090), body weight (r=0.118, t=0.865, P=0.392), and heart rate (r= -0.046, t=-0.284, P=0.776). The peak-value-time correlated negatively with peak signal intensity (r=-0.322, t=-2.56, P=0.016)and positively with duration of contrast (r=0.658, t=5.99, P=0.000). The peak signal intensity was negatively correlated with body weight(r=-0.356, t=-2.77, P=0.008). The linear regression analysis show b=-0.284, t=-2.285, P=0.026 between peak-value-signal and peak-value-time, b=-0.322, t=2.590, P=0.012 between peak-value-signal and body weight.Conclusion Mini-dose pre-injection test was more helpful to adjust the rate of contrast medium injection and determine the time delay during scanning. But the prediction of contrast peak-time based on age, body weight and heart rate was unreliable.