低场磁共振成像对卵巢巧克力囊肿与囊性畸胎瘤鉴别诊断价值的研究

目的 探讨低场磁共振成像(MRI)在卵巢巧克力囊肿与囊性畸胎瘤临床鉴别诊断中的价值.方法 回顾性分析经手术及病理证实的卵巢巧克力囊肿22例,囊性畸胎瘤13例,分析各自的MRI表现特点.结果 22例巧克力囊肿术前诊断正确19例,其中3例术前诊断为囊性畸胎瘤,MRI诊断符合率86％(19/22)；13例囊性畸胎瘤术前诊断正确12例,1例术前判断为巧克力囊肿,符合率92％(12/13).所有巧克力囊肿和畸胎瘤病例在SET1WI序列下均可见到病灶内高信号区.当使用短时间反转恢复序列(STIR)脂肪抑制序列时,所有高信号区可见不同程度信号减低；当使用GRE同、反相位T1加权成像时,畸胎瘤内的T1WI高信号病灶在反相位图像上会出现明显信号减低区,而巧克力囊肿不会出现信号减低区.结论 卵巢巧克力囊肿与囊性畸胎瘤MRI诊断准确性较高.使用GRE同、反相位T1加权成像对两者的鉴别诊断有特殊价值.

Value of low-field MRI in differential diagnosis of chocolate cyst of ovary and cystic teratoma

Objective To discuss the value of low field MR] in differential diagnosis of the chocolate cyst of ovary and the cystic teratom. Methods MRI findings of 22 cases with chocolate cyst of ovary and 13 cases with cystic teratoma confirmed by surgery and pathology were retrospectively analyzed. Results Among 22 cases, 19 cases were correctly diagnosed with chocolate cyst of ovary preoperatively, while 3 eases were diagnosed with cystic teratoma .The diagnostic accordance rate of MRI in chocolate cyst of ovary was 86%（19/22）. Meanwhile,12 cases of cystic teratoma were diagtlosed preoperatively, while 1 case was misdiagnosed as chocolate cyst of ovary .The diagnostic accordance rate of MR I in cystic teratoma was 92%（ 12/13 ）. In SE T~WI sequence, all the chocolate cyst and teratoma can be seen high signal area in the nidus. When using STIR fat suppression sequences, all high signal reduce visible in different degree. When using GRE in-phased and oppose-phased %WI, in oppose-phased image, it has signal reduce obvious within the high signal area in teratoma, but it did not occur of this phenomenon in chocolate cyst. Conclusion MRI has a high aecuracy in diagnosis of chocolate cyst of ovary and cystic teratoma, f/sing GRE in-phased and oppose-phased TjWI plays an important role in the differential diagnosis of chocolate cyst of ovary and cystic teratoma.