比较新型3D-T2 FLAIR序列与传统SE T1W、3D-SPGR、2D-T2 FLAIR序列的强化效果

目的 分析比较新型三维容积液体衰减反转恢复(3D-T2 FLAIR)序列与传统自旋回波T1加权(SE T1W)序列、三维容积扰相梯度回波(3D-SPGR)序列、二维液体衰减反转恢复(2D-T2 FLAIR)序列在不同浓度对比剂时的强化效果。 方法 将10只装有不同浓度对比剂的塑料试管按浓度由低到高顺序排列,在相同扫描序列和参数下采集10只试管和10名志愿者的头颅图像。计算图像信号的增强对比度(CER)、信号增强程度(SED)以及信号增强率(SER),绘制浓度-信号增强对比度关系曲线、浓度-信号增强程度关系曲线及浓度-信号增强率关系曲线。分析比较各个序列在不同浓度对比剂时的强化效果。 结果 新型3D-T2 FLAIR序列的CER及SED在低浓度的对比剂时较传统SE T1W、3D-SPGR、2D-T2 FLAIR序列高,而在高浓度时CER及SED较传统SE T1W、3D-SPGR、2D-T2 FLAIR序列低;新型3D-T2 FLAIR序列的SER较传统SE T1W、3D-SPGR、2D-T2 FLAIR序列低。 结论 新型3D-T2 FLAIR序列在常规剂量及更低剂量扫描中具有较大的临床应用价值,但肉眼观察对于新型3D-T2 FLAIR序列增强效果的敏感性较低。

Comparing the enhancement effect of new 3D-T2 FLAIR sequence with conventional SE T1W, 3D-SPGR and 2D-T2 FLAIR sequences

Objective To compare the enhancement effect of the new three dimensional fluid-attenuated inversion recovery (3D-T2 FLAIR) sequence with conventional spin echo T1 weighted (SE T1W), three dimensional spoiled gradient recalled (3D-SPGR) and two dimensional fluid-attenuated inversion recovery (2D-T2 FLAIR) sequences at different concentrations of contrast agent. Methods Ten plastic tubes filling with gadopentetate dimeglumine (Gd-DTPA) in different concentrations were prepared and arranged according to different concentrations. Ten plastic tubes and volunteers were scanned with the same sequence and parameters. Images' contrast enhancement ratio (CER), single enhancement degree (SED) and single enhancement rate (SER) were calculated, then concentrations-contrast enhancement ratio curve, concentrations-signal enhancement degree curve, concentrations-signal enhancement rate curve were drawed and the contrast enhancement effect of each sequences at different concentrations were analyzed. Results CER and SED of the new 3D-T2 FLAIR sequence were higher than conventional SE T1W, 3D-SPGR, 2D-T2 FLAIR sequences at lower dose, but were lower than those of conventional SE T1W, 3D-SPGR, 2D-T2 FLAIR sequences at higher dose. SER of the new 3D-T2 FLAIR sequence was lower than conventional SE T1W, 3D-SPGR and 2D-T2 FLAIR sequences at any concentrations. Conclusion New 3D-T2 FLAIR sequence has great potential value in clinical practice at conventional dose and lower, but with a less sensitivity with naked eye.