Yamashita Y, Miyazaki T, Hatanaka Y, Takahashi M
Department of Radiology, Kumamoto University School of Medicine, Japan.
J Comput Assist Tomogr. 1995 Sep-Oct;19(5):759-65. doi: 10.1097/00004728-199509000-00012.
To evaluate the appearance of contrast-enhanced dynamic MRI of small renal cell carcinoma (RCC) (< 3 cm diameter).
Twenty-seven patients with 28 small RCCs were studied by both conventional spin echo and contrast-enhanced dynamic MRI for tumor detection and characterization. All tumors were detected by contrast-enhanced CT and confirmed by operation. Dynamic MRI was performed using a breath-hold fast low angle shot technique after rapid injection of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA). Characterization of a renal mass was done by the visual analysis of tumor vascularity as well as quantitative assessment of the contrast noise ratio (CNR) and degree of enhancement.
With conventional spin echo MR and dynamic MR, 18 and 26 of 28 small RCCs were detected, respectively. In the dynamic study the tumor/renal medulla contrast was marked at 90-120 s after administration of Gd-DTPA (CNR:15.1). The tumor/renal medulla contrast in the dynamic study was more marked than that of postcontrast T1-weighted imaging (CNR, -0.25); T2-weighted imaging (CNR, 3.1); and T1-weighted imaging (CNR, -0.76).
Contrast-enhanced dynamic MRI is a useful technique for the diagnosis of small RCC especially in a patient with renal insufficiency or allergy to iodinated contrast material.
评估小肾癌（直径<3 cm）的对比增强动态磁共振成像（MRI）表现。
对27例患有28个小肾癌的患者进行了传统自旋回波和对比增强动态MRI检查，以检测肿瘤并进行特征分析。所有肿瘤均通过对比增强CT检测到，并经手术证实。在快速注射钆喷酸葡胺（Gd-DTPA）后，采用屏气快速低角度激发技术进行动态MRI检查。通过对肿瘤血管的视觉分析以及对对比噪声比（CNR）和增强程度的定量评估来对肾肿块进行特征分析。
分别通过传统自旋回波MR和动态MR检测到28个小肾癌中的18个和26个。在动态研究中，注射Gd-DTPA后90 - 120秒时肿瘤/肾髓质对比明显（CNR：15.1）。动态研究中的肿瘤/肾髓质对比比对比增强T1加权成像（CNR，-0.25）、T2加权成像（CNR，3.1）和T1加权成像（CNR，-0.76）更明显。
对比增强动态MRI是诊断小肾癌的一种有用技术，尤其适用于肾功能不全或对碘造影剂过敏的患者。
