3.0T动态增强磁共振对卵巢肿瘤的半定量及定量分析研究

目的：探讨动态增强磁共振半定量及定量分析方法在卵巢良、恶性肿瘤中的应用价值。材料与方法收集首诊经病理证实为卵巢恶性肿瘤组17例(包括原发卵巢腺癌9例、卵巢转移腺癌6例、卵巢淋巴瘤2例)，良性肿瘤或正常对照组15例(包括卵巢囊腺瘤5例、正常卵巢8例、卵巢囊肿2例)。均行3.0T 磁共振动态增强扫描，绘制时间强度曲线(time intensity curve，TIC)；并使用SIEMENS TISSUE 4D软件进行图像后处理，测得感兴趣区的Ktrans、Kep、Ve值。对良、恶性组的TIC曲线及定量灌注参数值进行统计学分析。结果卵巢良、恶性组TIC曲线形态存在明显不同(P＜0.05)；良性组均为I型曲线(100%)，恶性组中II型曲线所占比例最高(71%)。以I型曲线作为诊断良性标准，II型曲线作为诊断恶性标准，ROC曲线分析得出曲线下面积AUC为0.856。定量灌注参数值： Ktrans值分别是恶性组(0.166±0.077) min-1、良性组(0.071±0.025) min-1；Kep值分别是(0.455±0.172) min-1、(0.363±0.242) min-1；Ve值分别是(0.438±0.137)、(0.426±0.154)。恶性组平均Ktrans值比良性病变组高，且差异有统计学意义(P=0.000)；恶性组与良性组的平均Kep及Ve值比较差异无有统计学意义(P=0.218、P=0.821)。结论动态增强磁共振成像方法对卵巢良、恶性肿瘤有重要的鉴别诊断价值。良性肿瘤/组织多表现为I型曲线，恶性肿瘤多表现为II型曲线。定量参数Ktrans值对卵巢良、恶性肿瘤具有重要的鉴别诊断意义。

Semi-quantitative and quantitative parametric analysis of 3.0 T dynamic contrast-enhanced magnetic resonance imaging in diagnosing tumors of ovary

Objective:To evaluate the value of 3.0 T DCE-MR in diagnosing tumors of ovary.Materials and Methods:Thirty-two cases of ovarian lesions (17 were malignant, 15 were benign) were evaluated in our study. All cases were received dynamic contrast-enhanced scanning on 3.0 T MR. The raw data was processed by SIEMENS TISSUE 4D software and the signal intensity time curve (TIC) was obtained and analyzed. Pharmacokinetic modeling of Tofts with a modeled vascular input function was used for the quantitative measurements volume: transfer constant (Ktrans), reverse volume transfer constant (Kep), the extravascular extracellular space volume per unit volume of tissue (Ve). The correlation of these measurements at each groups were investigated. Compare TIC curve and the data of perfusion parameters of each groups.Results:Among 17 malignant tumors, 9 were cystadenocarcinoma and 6 were metastatic adenocarcinoma, 2 were lymphoma. 15 benign lesions included 5 cystadenomas, 8 normal ovaries and 2 ovarian cysts. 100% cases of benign lesions belong to Type I curve and 71% cases of malignant tumors belong to Type II curve. There was statistically significant difference in TIC curve between benign and malignant groups (P<0.05). If Type I curve was used as diagnostic criteria for benign and Type II for malignant, ROC resulted the AUC was 0.856. The mean value of perfusion parameters of the two groups were: Ktrans was (0.166±0.077) min-1 in malignant group and (0.071±0.025)min-1 in benign group, Kep was(0.455±0.172)min-1 in malignant group and (0.363±0.242) min-1 in benign group. Ve was(0.438±0.137) in malignant and (0.426±0.154)in benign group. Ktrans was signiifcantly difference between the malignant group and benign group(P=0.000).Conclusion:The Types of TIC and Ktrans value were important criterion in differentiating benign and malignant ovarian tumors in dynamic enhanced MR imaging. These parameters were important supplement for conventional morphology MR diagnosis.