直肠癌术前分期:磁共振成像与病理对照研究

MRI Diagnosis of Rectal Carcinoma

目的：分析直肠癌的 ＭＲＩ改变，评价 ＭＲＩ诊断直肠癌的价值。材料和方法：经手术和病理学证实的直肠癌 ２８例。用０．５Ｔ超导ＭＲＩ仪，体部线圈。扫描序列为ＳＥ Ｔ１ＷＩ和 ＦＳＥ Ｔ２ＷＩ。结果：ＭＲＩ检出病变的阳性率为８９．３％，ＭＲＩ确定病变向周围侵犯和淋巴结转移的准确性分别为８２．１％和 ８７．５％，分期的准确性为 ５７．１％。肿瘤ＳＥ Ｔ１ＷＩ呈低信号，ＦＳＥ Ｔ２ＷＩ为高信号，大的肿瘤内有坏死。结论：ＭＲＩ对直肠癌的诊断和分期有较大价值，但不能显示较小的病变，特别是位于直肠前壁下１／３的病变。病变越小ＭＲＩ分期越不准确。

Purpose: To analyse the TRI findings of rectal carcinoma and evaluate its diagnostic value. Materials and Methods: Twenty-eight cases (19 men, 9 women, aged 35-72years) of rectal carcinomas were examined with superconductive MR, body coil. The sequences were SE T1 WI and FSE T2 WI. Results: The positive rate, accuracy rate of perirectal invasion, lymphnode metastasis and staging by MRI in this series were 89.3%, 82.1s%, 89.3% and 57.1% respectively. The tumors were low signal intensity on T2 WI, high signal intensity on T2 WI. There were necrosis in large masses. Conclusions: MRI has high values in the diagnosis and staging of rectal carcinoma, but it may miss the small lesionsare, especially in the antenor 1/3 wall of rectum. The smaller the lesionsare, the more difficulty to stage.