脊柱旁髓外造血:临床特征及MDCT表现

Extramedullary Haematopoiesis in the Thorax: Tumor Characteristics and Multidetector-Row Computed Tomographic Manifestations

目的探讨胸廓内髓外造血（EMH）的临床表现和MDCT特征。方法回顾性分析2001年1月到2012年12月期间7例经病理确诊为胸廓内EMH患者的临床资料及影像学特征,包括病变位置、数目、大小、形态、内部密度、强化方式及有无坏死、脂肪、钙化和出血等。结果 7例胸廓内EMH患者实验室检测均发现血液系统异常;MDCT最典型特征：双侧脊柱旁沟多发圆形或类圆形等密度结节、肿块（与同层面相邻的肌肉组织相比）,无邻近骨质破坏,无脂肪变、钙化或出血;所有EMH均见强化（2例轻度强化、4例中度强化、1例明显强化）;5例EMH显示＂血管穿行征＂。胸廓内EMH典型的MDCT特征为双侧脊柱旁沟多发软组织肿块、无邻近骨质破坏,增强扫描常见＂血管穿行征＂。结论熟悉EMH典型影像学特征,结合相关血液系统疾病有助于后纵隔病变的鉴别诊断。

Objective The purpose of this article was to present the clinic manifestations and multidetector-row computed tomographic（ MDCT） features of the Extramedullary hematopoiesis（ EMH） in the thorax. Methods The clinical data and imaging features of 7 patients with pathologically proven EMH of the thorax between January 2001 and December 2012 were retrospectively analyzed by 2 radiologists. The masses were analyzed for location,number,size,external configuration,internal architecture,enhancement pattern,presence of necrosis,fat,calcification and bleeding. Results The salient clinical manifestations of EMH in the thorax were abnormal in the laboratory tests. The most typical findings on the MDCT scans were multiple paravertebral round or similar round isodense masses with a well-defined margin compared with the adjacent muscle tissue on both sides,but the absence of bone destruction. Adipose tissue did not exhibit necrosis,calcification or bleedings. All lesions demonstrated a certain extent of enhancement（ mild,2 cases; moderate,4 cases and marked,1 case）. An penetrated enhanced vessel was found in five cases on the enhancement MDCT images（ 5/7,accounting for 71. 4%）. Well-defined and bilateral paravertebral multiple soft masses with the absence of bone destruction,and with the ＂vessel-penetrating sign＂are characteristic findings of EMH of the thorax on MDCT. Conclusion The typical imaging features may be helpful in the differential diagnosis of posterior mediastinal masses in the thorax,when these characteristics are correlated with underlying blood diseases.