两种脂肪抑制技术在肝脏T_2WI序列扫描中的比较

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

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。

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 eases. Measured and cal- culated 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/cere- brospinal 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 homogenei- ty 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.