化学位移成像和反转恢复快速自旋回波成像在肝脏的应用价值

Evaluation of Chemical Shift Imaging and IR-HASTE Sequence in Hepatic Imaging

目的 评价化学位移成像和反转恢复快速自旋回波成像对肝脏病变的检出能力。材料与方法 45例肝脏病变患者在进行常规SET1WI和半傅立叶采集单次激发快速自旋回波 (half Fourieracquisitionsingle shotturbospin echo ,HASTE)T2 WI的同时 ,加用化学位移成像T1WI和反转恢复HASTE(IR HASTE)T2 WI。比较图像的信噪比 (SNR)、肝脾对比噪声比 (L SCNR)、病灶对比噪声比(CNR)及病灶检出率。结果 化学位移成像T1WI的SNR、L SCNR及CNR与SET1WI均无显著性差异 (P >0 .0 5 ) ,但却能检出SET1WI无法显示的局灶性脂肪浸润和脂肪肝。IR HASTE的SNR与HASTE相近 (P >0 .0 5 ) ,前者的L SCNR及实性病灶的CNR均显著高于后者 (P <0 .0 5 ) ,特别是对较小的实质性病灶。结论 化学位移成像T1WI能提高肝脂肪成分的检出率 ,IR HASTE能提高肝实性病变的检出率 ,两种成像方法可作为常规肝脏检查方法的有力补充。

Objective To evaluate the chemical shift imaging and IR HASTE sequence in the detection of hepatic lesions.Materials and Methods Conventional SE T 1WI, IR HASTE T 2WI, chemical shift imaging and IR HASTE sequences were performed in 45 patients. The signal to noise ratio (SNR), liver to spleen contrast to noise (L S CNR), lesion CNR and detection ratio of lesions were measured.Results SNR, L S CNR and CNR of chemical shift imaging were not significantly higher than those of SE T 1WI (P>0.05). The fatty infiltration of liver could be detected on chemical shift imaging, but couldn't be detected on SE T 1WI. The SNR of IR HASTE sequence was similar to that of HASTE (P>0.05), but the L S CNR and CNR of solid lesions, especially of small solid lesions, with IR HASTE sequence were significantly higher than that with HASTE (P<0.05).Conclusion Chemical shift imaging can increase the detection rate of hepatic fatty infiltration, while IR HASTE sequences can increase the detection rate of solid lesions. Both techniques may be regarded as a powerful complement to the conventional imaging.