肾上腺嗜酸细胞腺瘤CT和MRI表现特征分析

The characters of computed tomography and magnetic resonance imaging in adrenal oncoctyoma patients

目的总结肾上腺嗜酸细胞腺瘤（AOC）的CT和MRI表现特征，以提高对AOC的认识。方法回顾性分析2006年3月至2017年8月收治的经手术病理证实的11例AOC患者的临床和影像学资料。男3例，女8例。年龄24～65岁，平均46.8岁。实验室检查示2例皮质醇明显升高。11例均行CT平扫，其中9例行CT增强扫描；8例同时行MRI平扫和增强扫描。分析AOC在CT和MRI检查上的表现特征。结果11例（13枚）中，10例为单发，1例为单侧多发（3枚）。右侧5例，左侧6例。椭圆形10枚，圆形3枚。肿块直径1.4～9.9 cm，平均3.9 cm。13枚瘤灶中，9枚CT平扫表现为密度均匀的软组织肿块影；4枚密度不均匀，CT值32.6～48.6 HU，平均37.9 HU，其中1例内见点状钙化。9例增强扫描表现为轻度至明显不均匀强化（5例呈明显强化，2例轻度强化，2例中度强化），均具有延迟强化的特征。8例MRI平扫在T1WI上呈等信号或等低信号，T2WI压脂相上呈高信号为主混杂信号，反相位信号无明显减低；三期增强扫描均具有不同程度的不均匀延迟强化的特征。瘤周无邻近结构侵犯、淋巴结肿大及脏器转移征象。结论AOC CT平扫常表现为边界清楚的软组织密度影，MRI反相位像上信号无改变；多期增强扫描以明显不均匀延迟强化为特征。

ObjectiveTo summerize computed tomography（CT） and magnetic resonance imaging（MRI） appearances of the adrenal oncoctyoma（AOC）, and to improve the diagnostic accuracy.MethodsThe 11 cases imaging materials of AOC confirmed by pathology from March 2006 to August 2017 were analyzed retrospectively.There were 3 males and 8 females, aged from 24 to 65 years old（mean 46.8 years）. There were 11 cases with CT unenhanced scan in which 9 cases performed enhancing scan, 8 cases underwent unenhanced and enhanced MRI scan.ResultsOf 11 cases （13 lesions）, 10 cases were singular, 1 was unilaterally multiple（3 lesions）. 5 cases were located in the right side, 6 in the left side. 10 lesions presented oval, 3 were round. The diameters of all lesions ranged from 1.4 to 9.9 cm, with a mean of 3.9 cm. All lesions were shown well-defined soft-tissue density on plain CT scan, 69.2%（9/13）of whom were homogeneous, 30.8% were heterogenous. The CT value ranged from 32.6 to 48.6 HU, with a mean of 37.9 HU. In 9 cases, 5 masses were markedly enhanced, 2 were slightly enhanced and 2 were moderately enhanced, and all of them depicted prolongedly enhanced on triple-phase scan. The masses of 8 cases appeared isointensity or slightly hypointensity on T1WI, hyperintesity on fat-suppressed T2WI. The signal did not change on opposed-phase imaging. The lesions demonstrated heterogeneously prolonged enhancement to some degree on enhanced T1WI images. There was no peritumoral adjacent invasion, enlarged lymph nodes and metastasis.ConclusionsAOC usually presents soft-tissue density on unenhanced CT, no changing on MRI opposed-phase images. The tumors are characterized by markedly heterogeneously prolonged enhanced on enhanced CT and MRI.