常规MRI及DCE-MRI在卵巢肿瘤及肿瘤样病变诊断中的应用

Application of Conventional MRI and DEC-MRI in Diagnosis of Ovarian Tumors and Tumor Like Lesions

目的:提高常规MRI及DCE-MRI在卵巢肿瘤及肿瘤样病变的诊断准确率。方法:回顾性分析44例我院收治并经手术病理证实为卵巢肿瘤及肿瘤样病变的常规MRI及DCE-MRI影像表现。平扫参考指标:病灶大小(最大径)、形状(规则/不规则)、有无包膜、囊壁/分隔厚度、实性成分比例、T2WI信号、ADC值、盆腔积液;DCE-MRI参考Ktrans、Kep以及Ve值。结果:MRI平扫显示良、恶性肿瘤的病灶大小、形状、实性成分比例、囊壁/分隔厚度、T2WI信号混杂程度、盆腔积液量及ADC值差异有统计学意义(P<0.05);上述7项中ADC值参考价值最大,ADC取1.09×10^-3)mm^2/s为良恶性肿瘤阈值,小于阈值,考虑恶性。DEC-MRI良性肿瘤实性部分Ktrans、Kep以及Ve值显著低于恶性肿瘤,差异有统计学意义(P<0.05),Ktrans值参考价值最大,Ktrans值取0.091/min为良恶性肿瘤阈值,大于阈值,考虑恶性。分别以ADC值及Ktrans值敏感度、特异性、准确度、阳性预测值及阴性预测值代表MRI平扫及DCE-MRI各项指标,得出常规MRI敏感度85.7%、特异性91.3%、准确度88.6%、阳性预测值90.0%、阴性预测值87.5%;DCE-MRI上述各项指标为72.7%、81.8%、77.3%、80.0%、75.0%;常规MRI联合DCE-MRI检查敏感度95.2%,特异性100.0%,准确度97.7%,阳性预测值100.0%,阴性预测值95.8%。结论:常规MRI联合DCE-MRI用于卵巢肿瘤及肿瘤样疾病诊断及鉴别诊断能够提高诊断准确率。

Purpose: To improve the diagnostic accuracy of conventional MRI and DCE-MRI in ovarian tumors and tumor-like lesions.Methods: The routine MRI and DCE-MRI findings of 44 patients with ovarian tumors and tumorlike lesions confirmed by surgery and pathology results were retrospectively analyzed. The conventional MRI features included: lesion size(maximum diameter), shape(regular/irregular), capsular wall/septal thickness, solid component ratio, T2 WI signal intensity, ADC value and pelvic effusion;The DCE-MRI parameters included Ktrans, Kep and Ve value. Results: There were significant differences in size, shape, proportion of solid components, thickness of cyst wall/septum, mixed degree of T2 WI signal, amount of pelvic effusion and ADC value between benign and malignant tumors on plain scan of MRI(P < 0.05). Among the seven items mentioned above, ADC value was most valuable, and ADC value of 1.09 ×10-3 mm2 s-1 was set as the threshold between benign and malignant tumors.The tumor would be considered with malignancy when the ADC value of it was lower than the threshold. The values of Ktrans, Kep and Ve in the solid part of benign tumors on DEC-MRI were significantly lower than those of malignant tumors(P<0.05). The reference value of Ktrans was the largest. The Ktrans value of 0.091 min-1 was set as the threshold between benign and malignant tumors. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of ADC value and Ktrans value were used to represent the indices of conventional MRI and DCE-MRI. The results showed that the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of conventional MRI were 85.7%, 91.3%, 88.6%, 90.0%, 87.5%, and those of DCE-MRI were 72.7%, 81.8%, 77.3%, 80.0%, 75.0%. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of conventional MRI combined with DCEMRI were 95.2%, 100.0%, 97.7%, 100.0% and 95.8%, respectively. Conclusion: Conventional MRI combined with DCE-MRI can improve the diagnostic accuracy in diagnosis and differential diagnosis of ovarian tumors and tumor-like diseases.