儿童眼眶转移性神经母细胞瘤和绿色瘤的特征性MR表现

目的 分析儿童眼眶转移性神经母细胞瘤和绿色瘤的特征性MR表现。资料与方法 回顾性分析经手术病理证实的9例儿童眼眶转移性神经母细胞瘤和5例绿色瘤的CT和MRI表现。所有病例均行CT平扫以及MRI平扫和增强扫描。结果 14例CT表现均为眼眶不规则肿块和邻近的眶壁溶骨性骨质破坏，7例骨质破坏区邻近的颅内可见扁平不规则肿块。2例转移性神经母细胞瘤表现为眼眶肌锥外间隙肿块内有与眶外壁垂直的针状高密度影。14例MRI表现为眼眶肌锥外间隙略长T1、略长T2信号不规则软组织影，7例骨质破坏区邻近的颅内硬膜外间隙可见略长T1、略长T2信号扁平不规则肿块，增强后明显强化。14例双侧眶骨及蝶骨大翼，9例斜坡和双侧岩尖及2例双侧颞骨鳞部骨髓腔脂肪高信号影被略长T1、略长T2信号影取代，采用脂肪抑制的增强T1WI显示均有强化，强化程度与眼眶内肿块相似。结论 儿童眼眶转移性神经母细胞瘤和绿色瘤的眶壁和颅面骨MR表现具有特征，有助于诊断和鉴别诊断。

Characteristic MRI Findings of Metastatic Neuroblastoma and Chloroma in the Orbit in Children

Objective To analyze characteristic MRI findings of metastatic neuroblastoma and chloroma in the orbit in children.Materials and Methods The CT and MRI findings of 14 patients (9 metastatic neuroblastomas and 5 chloromas in the orbit) proven pathologically were analyzed retrospectively, all patients were performed with plain CT scan and pre-and postcontrast MRI scan.Results All patients showed a soft tissue mass with lytic bone destruction of orbital walls on CT. Sunburst pattern of periosteal reaction within the soft tissue mass was seen on CT in 2 children with metastatic neuroblastomas. The masses displayed intermediate signal intensity on T_1W images and heterogeneously high signal intensity on T_2W images in 14 cases. With gadolinium, tumors appeared markedly enhancement. Normal hematopoietic elements and fat were replaced by leukemic cells and metastatic cells were identified as diffusely identical signal intensity within the bone marrow of bilateral lateral orbital walls and greater wings of the sphenoid bone on precontrast T_1W images, and postcontrast T_1W images with fat suppression demonstrated extensive high signal intensity in the above regions in all patients.Conclusion Postcontrast T_1W images with fat suppression can demonstrate the characteristic MRI findings of the metastatic neuroblastoma and chloroma in the orbit in children, which can contribute to diagnosis and differential diagnosis. HJ8mm]