Kilickesmez Ozgur, Inci Ercan, Atilla Serhan, Tasdelen Neslihan, Yetimoğlu Burcu, Yencilek Faruk, Gurmen Nevzat
Department of Radiology, School of Medicine, Yeditepe University, Istanbul, Turkey.
J Comput Assist Tomogr. 2009 Nov-Dec;33(6):828-33. doi: 10.1097/RCT.0b013e31819f1b83.
The purpose of this study was to calculate the apparent diffusion coefficient (ADC) values of different renal and adrenal lesions to evaluate the ability of diffusion-weighted imaging in characterizing masses and determining malignancy.
A total of 52 patients consisting of 67 renal lesions and 28 patients with 33 adrenal lesions in addition to 50 healthy controls with normal kidneys were enrolled in the study. Diffusion-weighted imaging was performed with b factors of 0, 500, and 1000 s/mm2, and the ADCs of the normal kidney and renal and adrenal lesions were calculated.
The mean (SD) ADCs of the renal cortex and medulla of the control group were 2.08 (0.22) x 10(-3) and 1.94 (0.18) x 10(-3) mm2/s, respectively. Focal renal lesions were as follows: simple cysts (2.94 [0.20] x 10(-3) mm2/s), hemorrhagic cysts (1.71 [0.38] x 10(-3) mm2/s), angiomyolipomas (1.40 [0.21] x 10(-3) mm2/s), renal cell carcinomas (1.06 [0.39] x 10(-3) mm2/s), metastases (1.50 [0.13] x 10(-3) mm2/s), and hydronephrosis (1.54 [0.25] x 10(-3) mm2/s). The mean ADCs of all these pathologies were significantly different when compared with normal parenchyma. Diffusion-weighted imaging was also able to differentiate angiomyolipomas and hemorrhagic cysts from renal cell carcinomas. Adrenal lesions were subgrouped as adenomas (1.41 [0.27] x M10(-3) mm2/s), nonadenomatous solid masses (1.08 [0.28] x 10(-3) mm2/s), and cysts (2.82 [0.24] x 10(-3) mm2/s). The mean ADCs of adenomas were significantly different when compared with nonadenomatous solid masses and cysts.
Our findings show that ADC measurement has a potential ability to differentiate benign and malignant focal renal and adrenal lesions with the guidance of conventional sequences. When used alone, diffusion-weighted imaging may lead to misdiagnoses due to overlapping ADCs of the lesions.
本研究旨在计算不同肾脏及肾上腺病变的表观扩散系数（ADC）值，以评估扩散加权成像在肿块特征化及判断恶性程度方面的能力。
本研究共纳入52例患者，包括67个肾脏病变、28例伴有33个肾上腺病变的患者，以及50例肾脏正常的健康对照者。采用b值为0、500和1000 s/mm²进行扩散加权成像，并计算正常肾脏、肾脏及肾上腺病变的ADC值。
对照组肾皮质和髓质的平均（标准差）ADC值分别为2.08（0.22）×10⁻³和1.94（0.18）×10⁻³mm²/s。局灶性肾脏病变如下：单纯囊肿（2.94 [0.20]×10⁻³mm²/s）、出血性囊肿（1.7¹ [0.38]×10⁻³mm²/s）、血管平滑肌脂肪瘤（1.40 [0.21]×10⁻³mm²/s）、肾细胞癌（1.06 [0.39]×10⁻³mm²/s）、转移瘤（1.50 [0.13]×10⁻³mm²/s）及肾积水（1.54 [0.25]×10⁻³mm²/s）。与正常肾实质相比，所有这些病变的平均ADC值均有显著差异。扩散加权成像还能够区分血管平滑肌脂肪瘤和出血性囊肿与肾细胞癌。肾上腺病变分为腺瘤（1.4¹ [0.²7]×10⁻³mm²/s）、非腺瘤实性肿块（1.08 [0.28]×10⁻³mm²/s）和囊肿（2.82 [0.24]×10⁻³mm²/s）。腺瘤的平均ADC值与非腺瘤实性肿块及囊肿相比有显著差异。
我们的研究结果表明，在传统序列的引导下，ADC测量有区分肾脏及肾上腺局灶性良性和恶性病变的潜在能力。单独使用时，由于病变的ADC值重叠，扩散加权成像可能导致误诊。
