Bartolozzi C, Caramella D, Zampa V
Dipartimento di Fisiopatologia Clinica, Università degli Studi di Firenze.
Radiol Med. 1991 Sep;82(3):253-9.
Since the impact of MRI on the diagnostic evaluation of renal masses is affected by the intrinsic complexity of the modality, the problems related to the specific knowledge, on the part of the radiologist, of the examination itself to make a correct diagnosis are carefully analyzed. The problems related to the technical features of the equipment are presented as well, with a special emphasis on the still inadequate spatial resolution of MRI, and on its long acquisition time and unfavorable signal-to-noise ratio. On the other hand, its good contrast resolution is mentioned, which will be further improved by the new gradient-echo sequence (GRE) and by the use of paramagnetic contrast media. As for diagnostic problems, the results are analyzed of a series of 62 patients showing US "solid" renal mass. MRI allowed lesion detection in 59/62 cases, with 95.1% sensitivity. False negatives were due solely to the poor image quality determined by motion artifacts. MRI did not provide significant information in the structural evaluation of the lesions when tissue characterization was concerned, but was helpful in the correct assessment of necrotic foci (thus allowing the calculation of viable neoplastic mass) and in the detection of collateral vessels. Finally, the spatial relationships of the mass could be easily assessed by MRI, thanks to both its multiplanarity and to its good capabilities in the visualization of vascular involvement.
由于MRI对肾肿块诊断评估的影响受到该检查方式固有复杂性的制约，因此仔细分析了放射科医生在进行正确诊断时，因对检查本身的专业知识不足而产生的问题。文中还介绍了与设备技术特性相关的问题，特别强调了MRI目前仍存在的空间分辨率不足、采集时间长以及信噪比不佳等问题。另一方面，文中提到了MRI良好的对比度分辨率，新的梯度回波序列（GRE）以及使用顺磁性造影剂将进一步提高这一分辨率。关于诊断问题，分析了62例超声显示为“实性”肾肿块患者的系列研究结果。MRI在59/62例病例中检测到病变，敏感性为95.1%。假阴性仅归因于运动伪影导致的图像质量差。在涉及组织特征描述时，MRI在病变的结构评估中未提供重要信息，但有助于正确评估坏死灶（从而能够计算存活的肿瘤体积）以及检测侧支血管。最后，由于MRI具有多平面成像能力以及在显示血管受累方面的良好表现，能够轻松评估肿块的空间关系。
