呼吸导航与心电触发对兔肝脏磁共振成像应用比较

目的 比较1.5T磁共振扫描仪(Avanto)在呼吸导航技术和心电触发技术配合下对兔肝脏扫描成像质量的优劣.方法 分别应用呼吸导航技术和心电触发技术配合1.5T磁共振扫描仪对10只新西兰大白兔进行肝脏扫描,在保证图像平均信噪比(SNR)在1±0.1状态下,比较每种检查图像的优劣.扫描序列分别为TSE序列T_1加权、脂肪抑制T_1加权平扫及增强、T_2加权和脂肪抑制质子加权.结果 在心电触发配合下各个序列扫描图像质量均优于在呼吸导航下扫描所得图像,主要表现为前者受运动伪影干扰明显少于后者.结论 在SNR为1±0.1状态下.1.5T磁共振采用心电触发技术扫描兔肝脏所得图像质量优于采用呼吸导航时相同序列扫描所得图像,原因可能和兔的生理特点及2种不同门控方法的敏感度差异有关.

Comparative Study on Respiratory Navigator Echo and EGG Triggering for Liver MR Imaging in Rabbits

Objective To evaluate the predominant in the rabbits' liver MR imaging at Siemens 1. 5 T general MR scanner with respiratory navigator echo or EGG triggering. Methods 10 New Zealand rabbits underwent MR imaging under respiratory navigator echo and EGG triggering respectively , the sequences included Turbo spin-echo T_1 -weighted, fat suppress Turbo T_1 - weighted, Turbo spin-echoT_2 -weighted, fat suppress Turbo T_1 -weighted and fat suppress Turbo Proton-weighted. The image quality under both respiratory navigator and EGG triggering was compared with the signal to noise ratio (SNR) was keeping at 1±0.1. Results The image quality under EGG triggering was predominant to those under respiratory navigator echo in all sequences, the remarkable was that the disturbance by moving in imaging under EGG triggering was less than that using respiratory navigator echo. Conclusion Due to the physical characters of rabbits and the difference in sensitivity of the two gating methods, MR image quality under EGG triggering is superior to those under respiratory navigator echo at 1. 5T MR scanner with SNR is keeping at 1±0. 1.