磁共振3种T_2加权成像序列在胃癌中的成像质量对比

目的对1.5T磁共振（MRI）3种T2加权成像（T2WI）序列在胃癌中的成像质量进行分析评价,比较不同序列胃癌图像质量分级,以优化合适的1.5T MRI胃癌成像序列。方法经胃镜病理证实的18例胃癌患者进行术前MRI检查行快速恢复快速自旋回波（FRFSE）、脂肪抑制快速自旋回波（FS-FSE）和单次激发快速自旋回波（SSFSE）3个T2WI序列进行图像质量分析,比较各序列信噪比（SNR）、对比噪声比（CNR）间的差异;并对3个序列在胃癌的图像质量分级进行比较,分析各序列在胃癌MRI成像中的应用价值。结果 3种T2WI序列间的图像质量分级差异有统计学意义（P〈0.01）;FRFSE与SSFSE序列的信噪比及对比噪声比明显高于FS-FSE序列（P均〈0.05）;而FRFSE与SSFSE序列间信噪比及对比噪声差异无统计学意义（P〉0.05）;FRFSE与SSFSE序列明显优于FSFSE序列。结论 1.5T MRI进行胃癌检查时,T2WI序列可显示胃壁分层结构及可以鉴别病变内部组织成分,因而是胃癌MRI检查的重要的成像检查序列。分析各序列在胃癌MRI成像中的应用价值,有助于优化合适的成像序列。

Comparison of imaging quality among three kinds of MRI T2-weighted imaging sequences in gastric cancer

Objective To analyze and evaluate the imaging quality of three kinds of magnetic resonance （MRI）T2- weighted imaging （T2WI）sequences in gastric cancer and compare the picture quality grading in order to optimize the appropriate MRI imaging sequences for gastric cancer. Methods Collecting preoperative MRI pictures of eighteen patients with gastric cancer confirmed by endoscopy and pathology, the imaging qualities of its three kinds of T2 WI sequence including fast recovery fast spin echo （ FRFSE ）, fat-suppressed fast spin echo （FS-FSE） and single shot fast spin echo （SSFSE） were analyzed to compare the differences between signal-noise ratio（SNR） and contrast noise ratio（ CNR）, and the applied values of various sequences in MRI imaging of gastric cancer were analyzed. Results There was statistical difference in picture quality grading of the three sequences（ P 〈 O. O1 ）. The SNR and CNR of FRFSE and SSFSE sequences were all significantly higher than that of FS-FSE sequence（ all P 〈 O. 05 ）, while there was no significant difference between FRFSE and SSFSE sequences （ P 〉 O. 05 ）. The FRFSE and SSFSE sequences were obvious superior to FS-FSE. Conclusions For MRI imaging of gastric cancer,the T2WI sequences can show the layering structure of gastric wall and identify tissues components in the interior of lesions, so T2WI sequences are the important imaging sequences for MRI examination of gastric cancer. The analysis on applied value of various sequences in MRI imaging of gastric cancer will help to optimize appropriate imaging sequences.