卵巢卵泡膜细胞瘤磁共振影像特征的分析

Magnetic Resonance Imaging Features of Ovarian Thecoma

目的探讨卵巢卵泡膜细胞瘤的磁共振成像(MRI)表现,提高该病术前MRI诊断准确率。方法回顾性分析经手术病理证实的48例卵巢卵泡膜细胞瘤患者资料,根据病灶最大径分为≥5 cm和<5 cm组,重点分析病灶的部位、大小、形态、边界、囊变坏死、T1WI、T2WI平扫信号、DWI特征、强化特征、盆腔积液情况。并通过MRI影像表现进行诊断分数评价(最高为6分)。结果48例病灶均为单发。≥5 cm组39例:边界清晰37例,不清晰2例;囊变坏死35例;T1WI呈等信号23例,等低信号16例;T2WI呈等信号7例,等低信号23例,稍高信号9例;DWI呈高信号23例,混杂高信号16例;动态增强扫描均呈轻度强化;33例见不同程度盆腔积液。分数评价:6分33例,5分2例,4分2例,3分2例。<5 cm组9例:边界均清晰;囊变坏死3例;T1WI呈等信号3例,等低信号6例;T2WI呈等信号2例,等低信号4例,稍高信号3例;DWI均呈高信号;8例病灶动态增强扫描呈轻度强化,1例呈明显强化;4例见少量盆腔积液。分数评价:6分3例,5分1例,4分4例,3分1例。≥5 cm组盆腔积液(χ^2=6.680,P=0.010)和囊变坏死(χ^2=14.109,P<0.001)的发生率明显高于<5 cm组。病灶囊变患者中雌激素水平升高的人数明显多于未发生病灶囊变的患者(χ^2=5.847,P=0.016;列联系数=0.330)。结论卵巢卵泡膜细胞瘤较大的病灶DWI呈高或混杂高信号,多合并盆腔积液及囊变坏死,囊变坏死多见且范围较小。较小的病灶DWI呈高信号,囊变坏死少见。MRI分数评价结合患者年龄等因素有助于提高术前诊断准确率。

Objective To investigate the magnetic resonance imaging(MRI)findings of ovarian thecomas and improve the accuracy of preoperative MRI diagnosis of the disease.Methods A retrospective analysis of 48 patients with ovarian thecoma confirmed by operation and pathology was performed.According to the maximum diameter,the lesions were divided into≥5 cm and<5 cm groups and analyzed in terms of location,size,shape,boundary,cystic necrosis,T1WI/T2WI signals,DWI characteristics,enhancement features,and pelvic effusion.The diagnostic score was evaluated by MRI(the highest score was 6 points).Results All the 48 lesions were single.In the≥5 cm group(n=39),the tumor boundary was clear in 37 cases and unclear in 2 cases;necrosis was found in 35 cases;T1WI showed equal signals in 23 cases and equal low signals in 16 cases;T2WI showed equal signals in 7 cases,equal low signals in 23 cases,and slightly higher signals in 9 cases;DWI showed high signals in 23 cases and mixed high signals in 16 cases;dynamic enhanced scans showed slight enhancement in all cases;33 patients had different degrees of pelvic fluid;score evaluation showed 6 points in 33 cases,5 points in 2 cases,4 points in 2 cases,and 3 points in 2 cases.In the<5 cm group(n=9),all lesions had clear boundaries;cystic necrosis was seen in 3 cases;T1WI showed equal signals in 3 cases and equal low signals in 6 cases;T2WI showed equal signals in 2 cases,equal low signals in 4 cases,and slightly higher signal in 3 cases;DWI showed high signals;the dynamic enhancement of the lesions showed slight enhancement in 8 cases and significant enhancement in one case;a small amount of pelvic fluid was seen in 4 cases;score evaluation revealed 6 points in 3 cases,5 points in 1 case,4 points in 4 cases,and 3 points in 1 case.The incidences of pelvic effusion(χ^2=6.680,P=0.010)and cyst necrosis(χ^2=14.109,P<0.001)in the≥5 cm group were significantly higher than those in the<5 cm group.The number of patients with cystic lesions with elevated estrogen levels was significantly higher than that of patients without cystic lesions(χ^2=5.847,P=0.016;contingency coefficeient=0.330).Conclusions Large ovarian thecomas have high or mixed high signals on DWI;they are often accompanied by pelvic fluid and cystic necrosis,and the cystic necrosis is common and has small involvement.For small ovarian thecomas,DWI often reveals high signals,and cystic necrosis is rare.MRI score evaluation combined with patient’s age and other factors is helpful to improve the accuracy of preoperative diagnosis.