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目的探讨低场磁共振液体衰减反转恢复(FLAIR)序列T2WI成像参数的变化对脑脊液（CSF）内钆浓度检出的影响，为临床应用提供依据。方法分别采用新鲜熟蛋清模拟正常脑实质、浓度在0~8 mmol/L之间的钆喷替酸葡甲胺（Gd-DTPA）人工CSF溶液模拟CSF内不同的强化水平，使用0.35T机型，对样本行不同参数的FLAIR序列T2WI扫描，以明确各成像参数变化对CSF内钆浓度检出的影响。结果TEeff固定为150 ms，当TR从5000 ms延长到20000 ms（其TI随之从1600 ms延长至2800 ms）时，但其所能检出的最低钆浓度无变化，均约为0.0078 mmol/L。当TR和TI分别固定为7079 ms、2000 ms， TEeff从20 ms延长至280 ms时，其所能识别的钆剂浓度从0.0625 mmol/L降为0.002 mmol/L（P＜0.0001）。结论在0.35T场强的FLAIR序列T2W上，当TR超过5000 ms时，采用的TEeff越长，对CSF内钆剂的检出浓度越低，而延长TR/TI对其检出几乎无影响。“,”Objective To evaluate the effects of different fluid-attenuated inversion recovery (FLAIR) sequences on the detection of gadolinium concentration in artificial cerebrospinal fluid (CSF) at low field MRI. Methods Brain parenchyma and different enhancement in CSF were simulated with fresh hard-boiled egg whites and mixtures of artificial CSF and gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA), with the concentration ranging from 0 mmol/L to 8 mmol/L. Turbo FLAIR MR sequences at different values of repetition time (TR), inversion time(TI), and effective echo time (TEeff) were performed at 0.35-T MR scanner. The influence of the imaging parameters on the detection of gadolinium concentration in the artificial CSF was defined. Results At a fixed TEeff of 150 ms, when the TR were increased from 5000 ms to 20000 ms (thus the TI increased from 1600 ms to 2800 ms), the detectability for gadolinium concentration was about 0.0078 mmol/L and unchanged. At a fixed TR of 7079 ms and TI of 2000 ms, the discriminable gadolinium concentration was decreased from 0.0625 mmol/L to 0.002 mmol/L as the TEeff increased from 20 ms to 280 ms(P<0.0001). Conclusion When the TR is longer than 5000 ms in the T2-weighted FLAIR sequence at 0.35-T, the discriminable gadolinium concentration in CSF decreases with the increase of TEeff and is nearly unaffected by TR (TI) used.