节细胞神经瘤的CT及MRI表现

The imaging findings of ganglioneuroma

目的:探讨节细胞神经瘤的CT及MRI表现,旨在提高对该病的影像诊断水平。方法:搜集43例经手术病理证实的节细胞神经瘤的临床及影像资料,患者术前行CT或MRI平扫及多期增强扫描,结合文献回顾性分析其影像特征。结果:后纵隔脊柱旁19例(右侧14例,左侧5例);肾上腺10例(右侧7例,左侧3例);椎管内外多发6例,其中3例合并Ⅰ型神经纤维瘤病;1例合并Ⅱ型神经纤维瘤病;椎管内外单发2例;腹膜后5例。43例均边界清楚,25例呈椭圆形或梭形,9例呈类圆形,9例形态不规则。22例伴有伪足或呈嵌入式生长,13例脊柱旁病灶部分嵌入椎管内,造成相应椎间孔扩大。CT平扫9例出现钙化,30例CT增强扫描,其中22例动脉期及静脉期无明显强化,5例轻度不均匀强化,3例中度强化,9例延迟期可见条片状或絮状强化。MR T_1WI呈等或稍低信号,T_2WI以高信号为主,其中8例可见条索状稍低信号。12例MR增强扫描,其中8例呈轻度斑片状或絮状不均匀强化,1例呈明显不均匀强化。结论:节细胞神经瘤的影像表现具有一定的特征性,若病灶位于后纵隔、腹膜后或肾上腺,边界清楚,形态规则,呈伪足或嵌入式生长,密度/信号均匀,CT可见钙化或MR见漩涡征,增强扫描条索状或絮状轻度强化,应首先考虑诊断节细胞神经瘤。

Objective:The purposes of this study were to investigate the imaging features of ganglioneuroma and to improve the diagnostic accuracy. Methods:The imaging findings of 43 patients with ganglioneuroma confirmed by postoperative histopathology were reviewed retrospectively.Related literature was reviewed. Results:The number of tumors found at the posterior mediastinum was 19 (right 14,left 5),the adrenal gland 10 (right 7,left 3),multiple inside and outside vertebral canal 6,including 3 cases complicated with neurofibromatosis type Ⅰ and one with neurofibromatosis type Ⅱ,internal and external spinal canal 2,retroperitenealcavity 5.All 43 cases had clear margin with round or ellipse shape (n=25),circular (n=9) and irregular (n= 9).22 masses had pseudopodia or embedded growth,and 13 cases involved the intervertebral foramen.9 tumors had calcification on CT.30 cases underwent contrast enhanced CT scan.There were no obvious enhancement on arterial and venous phases in 22 cases,slight uneven enhancement in 5,moderate enhancement in 3,and delayed striped enhancement in 9.The tumor showed isointensity or slightly hypointensity on T 1WI and hyperintensity on T2WI including striped hypointensity in 8 cases.12 cases underwent MR enhanced scan.Slight patchy uneven enhancement were found in 8 cases,and significant uneven enhancement in one case. Conclusion:Ganglioneuroma has some imaging characteristics.The mass boundary is clear and regular when located at the posterior mediastinum,retroperitoneum cavity or adrenal gland with pseudopod or showed as embedded growth.The density/signal is uniform.Calcification can be seen on CT or swirl-like sign can be shown on MR.Tumor with stripe-like or patchy mild enhancement on CT or MR and features mentioned above should be firstly considered the diagnosis of ganglioneuroma.