眼眶横纹肌肉瘤的临床特点及影像学评价

Clinical and Imaging Features of Orbital Rhabdomyosarcoma

目的 探讨眼眶横纹肌肉瘤的临床特点及影像学表现。材料与方法 结合 16例经病理证实的眼眶横纹肌肉瘤的临床特点 ,回顾性分析其B超、CT和MRI特征。结果 眼眶横纹肌肉瘤主要临床特点为发展迅速的进行性眼球突出 ,眼眶内上象限为其好发部位。B超检查显示肿瘤为低或无回声区。 16例CT平扫 ,14例与眼外肌呈均匀的等密度 ,边缘清楚。 10例行增强扫描 ,明显强化 4例 ,中等强化 5例。骨质破坏 5例。 9例行MRI检查 ,T1 WI肿瘤与眼外肌呈等信号或略低信号 ,T2 WI呈高信号 ;6例行增强扫描 ,4例中等度强化 ,2例明显强化。在脂肪抑制和增强T1 WI上呈高信号。结论 超声、CT和MRI,尤其CT和MRI能较准确的显示横纹肌肉瘤的部位、形态和内部结构 ,结合临床特征 ,能较准确作出定性诊断 ,对临床选择治疗方案有重要价值。

Objective To discuss the clinical and imaging features of orbital rhabdomyosarcoma.Materials and Methods The clinical manifestations and imaging findings (CT, MRI, ultrasonography) in 16 patients with pathologically proved orbital rhabdomyosarcoma were retrospectively analyzed.Results The main clinical manifestation of orbital rhabdomyosarcoma was rapid progressive proptosis. The tumors were most commonly located at medial upper quadrant of the orbit. On sonogram, the lesions were manifested as low echo or echoless areas. On plain CT scan, the tumors were isodense in contrast with the muscles (n=14), and erosion of the adjacent bone was seen in 5 cases. Enhanced CT scan was performed in 10 cases. The lesions showed moderate enhancement in 5 and marked enhancement in 4 cases. The tumors displayed as iso or slightly hypo signal intensity in contrast to muscles on T 1WI, and hyper signal intensity on T 2WI. On post contrast fat suppression T 1WI, the tumors showed mild to moderate enhancement.Conclusion CT, MRI and ultrasonography can accurately demonstrate the location, inner structure and extent of the rhabdomyosarcoma, which is of great value for clinical management.