梯度回波化学位移成像用于诊断腹腔含脂病变的价值

Gradient-echo chemical shift imaging in detection of lipid-containing abdominal lesions

目的 评价梯度回波化学位移成像诊断腹腔含有脂质病变的价值。方法 把 35例腹腔病变分成含脂病变组和非含脂病变组。均行梯度回波同相 (in phase,IP)和反相 (opposed phase ,OP)扫描 ,观察这些病灶在IP和OP像上的显示情况 ;测定其信号强度 ,计算IP和OP像上信号强度变化率 ,并作非参数统计检验。结果 腹腔内含脂病灶在OP像上信号强度较IP像有明显下降 ,其信号强度变化率的中位数为 37.1% ,而非含脂病灶信号强度变化不大 ,中位数为 3.3 % ,两组差异有显著性意义 (u =4.5 6 ,P <0 .0 1)。结论 梯度回波化学位移成像简单实用 ,对检测腹部病变是否含有脂质有一定帮助。

Objective To evaluate the value of gradient echo chemical shift imaging in detection of lipid containing abdominal lesions. Methods 35 patients with abdominal lesions were divided into 2 groups according to whether or not they contained lipid. Breath hold in phase(IP) and opposed phase(OP) acquisitions were performed. The demonstration of these lesions on IP and OP was compared. The signal intensity of these lesions on both images was measured. The percentage of signal intensity variation on IP and OP was calculated and statistically analyzed with non parametric method between the 2 groups. Results For lesions containing lipid, the signal intensity dropped significantly from IP to OP, with median value of signal intensity variation attaining 37 1%. On the other hand, for lesions not containing lipid, the signal intensity did not change obviously between IP and OP, whose median value of signal intensity variation was 3.3%. The difference between the 2 groups was statistically significant ( u =4.56, P <0.01). Conclusion Gradient echo chemical shift imaging is an easy and practical way, helpful to detection of lipid component within abdominal lesions.