卵巢畸胎瘤的MRI诊断

MRI diagnosis of ovarian teratomas

目的:分析卵巢畸胎瘤的MRI表现,提高MRI诊断的准确性。方法:搜集经手术和病理证实的68例共70个卵巢畸胎瘤,对其MRI表现作回顾性分析。结果:70个畸胎瘤中,成熟性畸胎瘤65个,未成熟性畸胎瘤4个,卵巢甲状腺肿1个。65个成熟性畸胎瘤均为囊性,其中单房46个(71%),双房11个(17%),多房5个(8%),不完全分隔3个(4%);65个成熟畸胎瘤均见脂肪成分,其中58个(89%)肿瘤以脂肪成分为主,7(11%)个瘤内含少量脂肪成分;38个(58%)见头结节;20个(31%)瘤内见钙化或牙齿;58个(89%)瘤内见碎屑及毛发。增强后囊壁和较大头结节强化。4个未成熟性畸胎瘤均为囊实性,为混杂实性、液性、少量脂肪和钙化信号。1个卵巢甲状腺肿为双房囊性,不含脂肪成分,一分房内T2WI均匀极低信号。术前MRI正确诊断65个(92.9%)。结论:MRI能较好的显示卵巢畸胎瘤内部结构及成分,绝大多数畸胎瘤具有典型表现,脂肪含量少或不含脂肪的畸胎瘤易误诊。

Objective：To analyze MRI manifestations of ovarian teratomas to improve its diagnosis.Methods：MRI findings of 70 pathologically-proved ovarian teratomas in 68 patients were retrospectively analyzed.Results：Of 70 lesions,65 were matured,4 were immatured,and the remaining 1 was struma ovarii.All of the 65 mature teratomas were cystic,of which unilocular cyst was seen in 46（71%）,bilocular cyst in 11（17%）,incompletely separated cyst in 3（4%） and multilocular cyst in 5（8%）.The lipid component was found in all mature teratomas with prominent lipid component in 58 tumors,main aqueous fluid cyst with small fat in 7 tumors.Rokitansky nodule,debris and hair,and calcification or tooth were seen in 38（58%）,58（89%） and 20（31%） mature teratomas respectively.All of the 4 immature teratomas were heterogeneous,predominantly solid lesion with scattered small foci of fat,cystic spaces and calcifications.One struma ovarii demonstrated a bilocular cyst without lipid component,with very low signal in one loculation on T2W imaging.Conclusion：The majority of ovarian teratomas can be diagnosed by its characteristic MRI manifestations,whereas the minority without or with small adipose material can be nonspecific.