小肾癌的MRI诊断

目的:探讨小肾癌的MRI表现。方法:21例手术病理证实的小肾癌患者,肿瘤直径均为1.3～3.0cm,术前1个半月内行MRI检查,对MRI表现进行对比。结果:21例患者均被MRI检出,16例边界清楚,5例部分边界不清。18例病理检查有假包膜,MRI显示假包膜16例(16/18,88.89%)。平扫信号无特征性。11例MRI增强扫描中,4例不均匀强化,其增强程度低于肾实质;6例未见明显强化;1例为囊性,增强后囊壁及分隔有强化。MRI分期诊断准确率为80.95%(17/21)。结论:小肾癌MRI的信号复杂多变,假包膜的出现有助于诊断,静脉增强扫描信号取决于肿瘤血供。MRI有利于小肾癌的检出和分期。

MRI Diagnosis of Small Kidney Neoplasms

Objective:To study the MRI features of small kidney neoplasms(diameter<3cm).Methods:21 patients with pathologically proved small kidney neoplasms were examined by MRI in one month and a half before surgery of nephrectomy.The MRI appearances were nanalysed.Results:All small kidney neoplasms were detected by MRI images.16 cases had clearly boundary and 5 had not.16 cases had pseudocapsule in MRI(16/18,88.89%).Signal intensities of small kidney neoplasms had not characteristic in plain scan,included renal deformation,cortex-medulla demarcation disappearance,and the presence of pseudocapsule.After intravenous administration of contrastmedia in 11 cases,the signal intensities were as following:4 were in asymmetrically enhanced and less than that of the normal renal substance;6 were not enhanced obviously;1 cysts were enhanced in the regions of the cystic wall and the septum.Compared with the surgical results,the accuracy rate of MR in staging of small kidney neoplasms was 80.95%(17/21).Conclusion:The focal signals of small kidney neoplasms are diverse and complicated,and the findings of dynamic enhanced scanning are related to the blood supply.The presence of pseudocapsule is helpful in the diagnosis of small kidney neoplasms.MRI is useful in the detection and staging of small kidney neoplasms.