嗜铬细胞瘤的影像学诊断(附25例分析)

目的　旨在提高嗜铬细胞瘤的影像诊断水平。方法　收集经手术病理证实的嗜铬细胞瘤 2 5例 ,共 2 8个病灶 ,其中 2 5个病灶为肾上腺髓质嗜铬细胞瘤 ,3个病灶为肾上腺外嗜铬细胞瘤 ,即异位嗜铬细胞瘤。 2 4例行B型超声检查 ,17例行CT检查 ,9例行MRI检查 ,回顾性分析其超声、CT或MRI征象。结果　声像图特征 :肿块多呈圆形或椭圆形 ,部分为不规则形有分叶 ,多可见回声明亮的肿瘤边界 ,肿块较小的多为均质的低回声 ,较大的多为实液混合性的高回声。CT表现 :肿块常较大 ,密度不匀 ,强化明显。MRI信号特征 :信号多不均匀 ,T1WI多为低信号 ,T2 WI特征性的表现为高信号 ,增强后明显强化。MRI、CT和B超的定位诊断率分别为 10 0 %、95 %和93% ,三者的诊断符合率分别为 91%、89%和 85 %。结论　嗜铬细胞瘤的B型超声、CT和MRI表现各具有一定的特征 ,结合临床表现多可明确诊断。

Imaging characteristics of pheochromocytoma (report of 25 cases)

Objective To improve the diagnosis accuracy of pheochromocytoma. Methods 25 cases of pheochromocytoma confirmed by pathology were collected and analyzed retrospectively. B-mode ultrasonography (US) was performed in 24 cases and computer tomography (CT) was performed in 17 cases and magnetic resonance imaging (MRI) was performed in 9 cases. 25 of 28 lesions were adrenal pheochromocytoma and the other three were extra-adrenal pheochromocytoma.Results The image characteristics of B-mode ultrasonography showed that the shapes of most masses were round or elliptical or irregular; light-echo zone was seen around the bounder of the mass; the well-distributed lower echo region could be seen in small masses and the high-echo region mixed with liquid and parenchyma could be seen in large masses. On CT, the size of masses was usually large and the density was often irregular and marked enhancement after intravenous contrast material. On MRI, the signal tended to be hypointense on T-1-weighted and hyperintense on T-2-weighed image showed marked enhancement after intravenous contrast material. The location accuracy rate of MRI , CT and US was 100%, 95%, 93%, respectively. The qualitative accuracy rate of MRI , CT and US was 91%, 89%, 85%, respectively. Conclusion The B-mode ultrasonography ,CT and MRI findings of pheochromocytoma carry certain characteristics. For most patients, a reliable diagnosis might be made when combined imaging findings with clinical information.