前列腺炎的MRI及MRS初步研究

The Initial Study of MRI and MRS in Prostatitis

目的研究前列腺炎外周带的MRI表现及MR波谱(MRS)特征。资料与方法 21例前列腺炎患者行MRI平扫加MRS成像,观察前列腺外周带的信号形态及信号强度,同时计算感兴趣区的胆碱(Cho)+肌酸(Cre)/枸橼酸盐(Cit)比值。结果 21例前列腺炎患者平均前列腺特异抗原(PSA)水平是31.80 ng/ml。2例呈非结节局灶低信号,10例显示为双侧外周带弥漫低信号,3例显示为一侧外周带弥漫低信号,1例显示为结节状局灶低信号,其余5例没有信号异常。14例MRS谱线示Cho峰升高,Cit峰下降或消失,另7例MRS谱线正常,21例(Cho+Cre)/Cit均值为6.44。结论前列腺炎外周带低信号(T2WI)对前列腺癌并不具有特异性,前列腺炎的MRS谱线可类似于前列腺癌的波谱特征,可导致前列腺癌的假阳性诊断。

Objective To discuss MRI and MRS features of prostatitis in the peripheral zone.Materials and Methods MR imaging and three-dimensional MR spectroscopic imaging were performed retrospectively in 21 patients.The changes of signal intensity（SI）in the peripheral zone of prostate were observed.On MR spectroscopic imaging,ratio of choline plus creatine to citrate was calculated.Results In the 21 patients,mean pretreatment prostate-specific antigen level was 31.80 ng/ml.2 patients had non-nodular focal low SI,10 patient showed diffuse low SI.3 patient showed diffuse low SI in one side,1 patient showed nodular focal low SI.The remaining 5 patients had no abnormal intensity.14 of 21 patients demonstrated elevated choline peak and citrate peak was reduced or disappeared.In 7 patients,the normal MRS findings were seen.The mean value of Cho＋Cre/Cit was 6.44.Conclusion On MR spectroscopic imaging,prostatitis may demonstrate metabolic abnormality that leads to false-positive diagnosis of prostate cancer.The MRI findings in prostatitis are low SI in the peripheral zone,which was not specific for prostate cancer.