肾嗜酸细胞瘤的MRI表现

目的提高肾嗜酸性细胞腺瘤的影像诊断水平。方法回顾性分析6例经手术病理证实的肾嗜酸细胞瘤患者的MR表现。结果5例为单发肿瘤，1例并发肾透明细胞癌。肿瘤呈圆形或类圆形。直径1．5～3．8cm，境界清晰，均位于肾皮质区，向肾外突出。MR平扫，3例T1WI呈等信号，3例呈等低信号，其中1例中央可见裂隙状瘢痕更低信号；T2WI上3例呈等低信号，肿瘤内有混杂稍高信号，1例呈等稍低信号，中央瘢痕呈裂隙状高信号，2例呈低信号。动态增强扫描3例呈明显均匀强化；1例呈不均匀强化，但肿瘤实质部分强化均匀，中央瘢痕大部分延迟强化，少部分无强化；2例动脉期及静脉期扫描均呈“轮辐”状强化。结论MR检查能很好地显示肾嗜酸性细胞瘤，对临床诊断有帮助。

MRI manifestations of renal oncocytoma

Objective To analyze the MRI findings of renal oncocytoma, and to improve the ability for the diagnosis. Methods We retrospectively review MRI findings of 6 cases of renal oncocytoma which proved by pathology. Results Six cases had solitary lesion in each, and 1 of them accompanied with renal clear-cell carcinoma. Tumors appeared as round with diameter 1.5 to 3.8 cm, and well-defined margin. On T1WI, 3 tumors showed hypo-intensity, and 3 had iso-intensity. On T2WI, 3 tumors were iso- to hypo-intensity mixed with slightly hyperintensity, 1 tumor was iso- to hypo-intensity with center star-like high signal, and Low signal was detected in 2 tumors. Dynamic scan demonstrated that homogenous enhancement in the 3 tumors, heterogenous enhancement in 1 tumor, with parenchyma part of tumors with homogenous enhancement , and center scar delayed enhancement. Another 2 tumors were showed as spoke-like enhancement . Conclusion MR could demonstrate renal oncocytoma and it could be helpful to the diagnosis.