两种快速T_2WI在胎儿异常诊断中的比较研究

Comparison of two kind of Fast T_2W MRI Sequences in the Diagnosis of Fetal Abnormalities

目的比较两种快速T2W序列行胎儿MRI扫描的理想程度。资料与方法对31例胎儿进行快速稳态进动采集(FIESTA)及单激发快速自旋回波(SSFSE)序列扫描,记录扫描时自动产生的特异性吸收率(SAR),并对图像清晰度分级。分别进行统计学检验,并将两种序列的诊断结果与产后比较。结果FIESTA及SSFSE序列的SAR值分别为2.81±0.09及2.60±0.22。图像优良率分别为71%及42%。诊断正确率分别为93.5%(29/31)和80.6%(25/31)。结论FIESTA序列在显示胎儿病变方面比SSFSE序列更为理想。

Objective To compare the two kind of T2 W sequences in the diagnosis of fetal abnormalities. Materials and Methods Two kind of T2 weighted images included fast-imaging employing steady-state acquisition （FIESTA） and single-shot fast spin echo （SSFSE） were applied for MR examination. Specific absorption rate （SAR） and the image definition were recorded classified. MR results were compared with the clinical findings after birth. Results The SAR of FIESTA and SSFSE were 2.81±0.09 and 2.60 ±0.22. The image definition of FIESTA and SSFSE were 71% and 42%. The diagnostic correctness of FIESTA and SSFSE were 93.5 % （ 29/31 ） and 80.6% （ 25/31 ） respectively. Conclusion When SAR value is controlled under 3.0W/KG, FIESTA can show fetal abnormalities more clearly than SSFSE sequence.