骨内脂肪瘤的影像学诊断

Imaging Features of Intraosseous Lipoma

目的讨论骨内脂肪瘤的发病机制、临床特征、影像表现、诊断及鉴别诊断。方法回顾性分析经手术病理证实的11例骨内脂肪瘤的临床及影像资料,11例均行X线、CT检查,2例行MRI检查。结果X线平片表现边界清晰的不规则形透亮区,可伴硬化缘。CT上病灶为类圆形或不规则形的脂肪密度区,CT值-55^-120HU,病灶边界不规则,伴有厚薄不一的硬化缘,5个病灶中心可见结节状钙化灶。MRI表现为T1WI高信号,T2WI稍高信号,脂肪抑制序列病灶信号受抑变低,边缘见长T1短T2信号,其内见线条状长T1短T2信号的纤维分隔及长T1长T2的液性囊腔。结论结合发病年龄、病变部位、临床症状和影像学表现,对本病可作出正确的术前诊断,可避免不必要的穿刺活检和CT、MRI的重复检查。

Objective：To investigate the clinical and imaging manifestations of intraosseous lipoma. Methods：Clinical and imaging features of 11 cases with intraosseous lipoma （7 men, 4 women;mean age 65.4 years） were retrospectively analyzed. All patients had radiography and CT examinations, 2 cases had MRI additionally. Results： All of the lesions showed as a well-defined, irregular radiolucent area with a sclerotic rim on X-ray film. Oval or irregular shaped adipose attenuated area （CT value：-55-- 120HU） with thin or thick sclerotic rim was showed on CT images, intralesional calcification in the center of the focus was present in 5 lesions. MRI imaging demonstrated high signal intensity on T1WI and T2 WI as well as hypointensity on fat suppression sequence （STIR）. Fibrous septa and fluid filled cystic area within the lesion showed long T1 and short T2 and long T2, long T2 signal respectively. Conclusion：The age of patient, location of lesion, clinical and imaging manifestations provides important information for the diagnosis of intraosseous lipoma, unnecessary biopsy and followup CT/MRI could be prevented.