两种脂肪抑制技术在肝脏T2WI序列扫描中的比较

目的比较精准频率反转恢复(SPAIR)和频率选择饱和(FS)两种脂肪抑制技术的肝脏T2WI序列(结合BLADE和呼吸门控技术)的图像质量,探讨更适合该序列的抑脂技术。方法回顾性的分析25例正常肝脏T2WI-BLADE-Resp/Trigger抑脂序列的图像,每例均用SPAIR和FS两种脂肪抑制技术扫描,其它参数一致。测量并统计腹部皮下脂肪的均值M、变异系数CV、肝脏的信噪比SNR、肝脏与脾脏及肝脏与脑脊液的对比噪声比CNR1,CNR2。结果 SPAIR抑脂序列图像的腹部皮下脂肪均值M(30.58±8.05),变异系数CV(0.46±0.11)分别小于FS抑脂序列,其差异有统计学意义(P<0.05);肝脏的信噪比SNR(69.20±16.75)、肝脏与脾脏的对比噪声CNR1(81.60±17.86),肝脏与脑脊液的对比噪声比CNR2(181.90±39.80)分别高于FS抑脂序列,其差异有统计学意义(P<0.05)。结论 SPAIR抑脂序列图像的脂肪抑制程度、均匀性好,信噪比和对比噪声比高,是肝脏T2WI-BLADE-Resp/Trigger抑脂序列的首选抑脂技术。

Comparison of two kinds of fat suppression techniques in T2-weighted-imaging sequence of liver

Objective To compare the imaging quality and adaptability between two kinds of fat suppression techniques,SPAIR(Spectral Attenuated Inversion Recovery) and FS(frequency selective presatuation) in T2-weighted-imaging of liver. Methods Retrospectively evaluated T2WI-BLADE-Resp/Trigger with both SPAIR and FS techniques in 25 normal liver cases.Measured and calculated the M(mean value) and CV(coefficient of variance) in abdominal subcutaneous fat,SNR(signal-to-noise ratio) in liver tissue,CNR(contrast-to-noise ratio) between liver and spleen/cerebrospinal fluid. Results The data showed M(30.58±8.05) and CV(0.46±0.11) in SPAIR group were lower than those in FS group(P<0.05),SNR(69.20±16.75)in liver tissue,CNR between liver and spleen(81.60±17.86)/cerebrospinal fluid(181.90±39.80)(P<0.05). Conclusions The homogeneity and the degree of fat suppression with SPAIR is better than that with FS,could be the first choice in T2WI-BLADE-Resp/Trigger of liver.