儿童肾母细胞瘤的MSCT诊断

目的探讨儿童肾母细胞瘤的MSCT表现特点,以期提高影像诊断准确率。方法回顾性分析45例经手术及病理证实为肾母细胞瘤的患儿资料,男23例,女22例,最小年儿童肾母细胞瘤多见于4岁以下儿童,最小年龄为3个月,最大年龄为11岁,平均2.9岁;采用Philips Brilliance 16,先予平扫,再使用2ml/kg造影剂欧乃派克静脉团注后立即扫描,并行多平面重建（MPR）及最大密度投影（MIP）重建。结果全部为密度不均匀肿块,单侧多见,上极多于下极,肿瘤不均匀强化,常伴坏死、出血,少数有钙化;残存肾呈新月形强化为典型CT表现,肿块可跨过中线,但不包绕腹膜后大血管;腹膜后、膈脚后淋巴结转移最多见。MPR、MIP重建可清晰显示血管受累情况。结论儿童肾母细胞瘤多见于4岁以下儿童,MSCT表现有一定的特点,肿瘤呈不均匀强化,残存肾呈新月形强化为其典型表现,有助于本病的诊断。

MSCT Diagnosis of Nephroblastoma in Children

Objective To analyze the MSCT features of nephroblastoma （Wilms＇ tumor）, and to improve the diagnostic accuracy of nephroblastoma. Methods Imaging studies of 45 patients with proven nephroblastoma by surgery and histopathology were reviewed, including 22 females and 23 male, and the mean age was 2.9 years old. The Philips Brilliance 16-slice CT was used with the following acquisition parameters： 5-mm slice thickness, and 5-mm slice interval. Enhanced scanning was performed after high-pressure injection of 2ml/kg （300 mg/ml） non-ionic contrast agent. The images were reprocessed by multiplanar reformation （MPR） and maximum density projection （MIP） reconstruction. Results All lesions in our study presented masses of heterogeneous density. Most tumors were unilatera. There were more tumors appear in the upper pole of kidney than that in the lower pole. The masses showed uneven enhancement, often with necrosis, hemorrhage and cystic changes, and few tumors had calcification. Typical radiographic findings in patients with nephroblastoma were that the remaining kidney presented crescent-shaped enhancement. Most masses crossed the body center line, but none crossed around the main blood vessel in retroperitoneum. The metastatic lymph nodes were mostly seen in retroperitoneal or posterior to diaphragmatic crus. The performance of the vascular involvement was displayed clearly through MPR and MIP reconstruction. Conclusion The nephroblastoma often occur in children under the age of four. The manifestations of nephroblastoma in MSCT had certain characteristics. The masses could have uneven enhancement and the presence of crescent-shaped enhancement can be contribute to the diagnosis of nephroblastoma.