肾上腺神经节细胞瘤的影像特征表现

Imaging features of primary adrenal ganglioneuroma

目的分析肾上腺神经节细胞瘤(adrenal ganglioneuroma,AGN)的CT及MRI特征表现,提高对AGN影像特征的认识。方法回顾性分析经病理证实的29例AGN患者的影像学特点,28(28/29)例行CT检查,8(8/29)例行MRI检查,7(7/29)例同时行CT、MRI检查。结果29例均为单侧发病,位于左侧10例、右侧19例。肿瘤最大径1.9~12.5 cm,平均(5.0±3.0)cm,12例形态不规则呈水滴状生长,3例多囊样改变,其中1例跨中线生长,对侧肾上腺受压推移。CT表现:平扫密度均匀17例,因囊变、钙化和含脂而密度不均11例,CT值21.9~43.4 HU,平均(32.4±6.2)HU;增强后轻中重度强化22例,无强化6例,动脉期CT值22.9~59.2 HU,平均(37.7±8.5)HU,动脉期平均增幅为(5.3±5.9)HU;静脉期CT值24.1~65.8 HU,平均(46.6±10.4)HU,静脉期平均增幅为(14.2±9.3)HU。MRI表现:8例实性部分表现为等T_(1)等长T_(2)信号,4例行DWI序列检查,未见明显弥散受限,ADC平均值为(1.55±0.11)×10^(-3) mm^(2)/s,6例增强检查,5例条片状或条索状强化,1例无强化。结论AGN影像表现具有一定特征性:CT密度均匀,偶见囊变,部分呈多囊样改变,较大者呈水滴样生长且可跨中线生长,增强静脉期强化较明显;MRI弥散不受限,条片状强化有一定特征性。

Objective To discuss the imaging features of CT and MR of adrenal ganglioneuroma(adrenal ganglioneuroma,AGN)and to improve the imaging diagnostic level of adrenal ganglioneuroma.Methods The imaging features of 29 patients with biopsy or pathology confirmed AGN were retrospectively analiezed.28(28/29)patients underwent CT examination,8(8/29)patients underwent MR examination,and 7(7/29)patients underwent both CT and MR exminations.Results All of 29 cases were unilateral(19 on the right,10 on the left).The maximum diameters ranged from 1.9 cm to 12.5 cm(M±SD 5.0±3.0 cm).12 cases were irregular teardrop-shaped,3 cases presented with polycystic change,1 case appeared cross-neutral growth,with compression of the contralateral adrenal gland.CT imaging 17 case showed homogeneous density,11 cases were heterogeneous on plain scan with cystic change,fat or calcification.The CT values ranged from 21.9 to 43.4 Hounsfield units(HU,mean 32.4±6.2)HU,22.9 to 59.2 HU(mean 37.7±8.5)HU and 24.1 to 65.8 HU(mean 46.6±10.4)HU.22 cases were mild or moderate enhancemen,and 6 case were no enhancement.MR imaging the solid parts of 8 AGNs were iso-signal intensity in T_(1)WI and hyper-signal intensity in T_(2)WI;4 patients underwent DWI examination,no significant diffusion limited,the average value of ADC was(1.55±0.11)×10^(-3) mm^(2)/s,6 patients underwent MR enhancement,5(5/6)cases shwoed sheetlike reinforcing cords,1(1/6)case had no enhancement.Conclusion AGN imaging findings have a certain characteristic.CT showed homogeneous density,occasionally cystic and polycystic change;drop-like growth is greater and grows across the line;venous phase is progressing enhancement;MRI diffusion is not limited,and a sheet-like reinforcing strip has a certain characteristic.