通讯作者:方友强,Email:fang1573@126.com
目的 探讨CT 平扫及动态增强扫描在肾血管平滑肌脂肪瘤与肾透明细胞癌鉴别诊断中的临床应用价值。方法 回顾性搜集CT 误诊为肾癌的肾血管平滑肌脂肪瘤(AML)16 例及肾透明细胞癌(ccRCC)30 例患者的CT 平扫及动态增强扫描资料,由2 名影像医师分别独立评价肿瘤形态特征如有无钙化、假包膜、劈裂征、喙征;测量乏脂肪肾血管平滑肌脂肪瘤(fpAML)和(ccRCC)CT 平扫及增强扫描各期的CT 值、计算强化指数,进行独立样本t 检验。结果 平扫fpAML 肿瘤CT值为(44±9)Hu,ccRCC 平扫CT 值为(31±4)Hu,差异有统计学意义(P<0.05),增强扫描各期CT 值两者间差异无统计学意义(P>0.05)。fpAML 与ccRCC 皮质期、实质期、排泄期强化指数比较,差异有统计学意义(P<0.05)。实质期fpAML75% 强化较为均匀一致,而ccRCC 组93.3% 表现为强化不均匀。结论 fpAML 平扫CT 值明显高于ccRCC,增强扫描fpAML 在皮质期、实质期和排泄期强化程度均低于ccRCC,实质期fpAML 强化较为均匀一致,ccRCC 强化不均匀。这三点是fpAML与ccRCC 重要的CT 鉴别诊断要点。
Objective To evaluate the clinical value of CT plain scan and dynamic contrast enhanced scan in the differential diagnosis of renal angiomyolipoma and renal clear cell carcinoma. Methods CT scan and dynamic enhancement scan data were collected from 30 patients with renal clear cell carcinoma (ccRCC) and 16 cases of renal angiomyolipoma which were misdiagnosed as RCC. Two radiologists retrospectively evaluated the morphological features (i.e. split sign, beak sign, with or without pseudocapsule and calcification) and enhancement features (i.e.CT value of ROI in each phase, the enhancement index of each phase. For the parameters that ha d statisticall differences between the two groups, we calculated the P values by using the independent sample t test. Results The CT value of fpAML tumor was (44±9) Hu, and the CT value of renal clear cell carcinoma was (31±4) Hu (P<0.05). The enhancement index of fpAML was less than ccRCC in cortical phase, nephrographic phase and excretory phase(P<0.05). In nephrographic phase,75% of fpAML showed a homogeneous enhancement, while 93.3% of ccRCC showed heterogeneous enhancement. Conclusion In this study, we confirmed common imaging features of fpAML are different with ccRCC:higher attenuation on unenhanced CT sequences; less enhancement on enhanced phases, more uniform enhancement in nephrographic phase.