胸腰椎骨纤维结构不良的影像学诊断

Imaging diagnosis of monostotic fibrous dysplasia of thoracic and lumbar spines

[目的]总结胸腰椎骨纤维结构不良的影像学特征,提高对本病的影像学诊断水平。[方法]回顾性分析5例胸腰椎骨纤维结构不良的X线、CT与MR I资料,总结其影像学特征。[结果]胸腰椎骨纤维结构不良X线表现为圆形或椭圆形囊状低密度影,有清晰的硬化带与周围正常骨组织间隔。CT表现为类圆形低密度影,边界清晰,边缘有完整骨质硬化带,骨皮质略微变薄但连续性未有破坏。MR I表现为T1W I中均匀长T1信号,T2W I中病灶呈混杂偏低信号,在T1W I、T2W I及质子像中病灶周围均有较完整的低或极低信号环状带;增强扫描时病灶信号明显强化。[结论]胸腰椎骨纤维结构不良具有独特的影像学特征,完全不同于骨纤维结构不良发生在脊柱以外的影像学表现,掌握这些特征是正确地做出影像学诊断的关键。

[ Objective] To analyse the imaging findings of thoracic and lumbar fibrous dysplasia and evaluate the imaging characteristics. [ Method] Among 5 cases of monostotic fibrous dysplasia of thoracic and lumbar spines, 4 were imaged with CT scarfing, 2 with MRI and 5 with X-ray. All materials were analysed. [ Result] Each X-ray revealed a round or oval radiolucent lesion surrounded by a distinct and thick rim of sclerosis. CT showed a round or oval low-density lesion with a high-density borderline between the lesion and normal vertebral bone tissue. Bone cortex remained intact in all cases. The lesion showed homogeneous long T1 signal on T1WI and hypo-or isointensity signal on T2WI. There was a characteristic hypointensity loop surrounded the lesion on T1WI, T2WI and PdWI. The lesion was demonstrated obviously in the contrast enhancement of scanning. [ Conclusion] Monostotic fibrous dysplasia of thoracic and lumbar spine shows distinctive imaging characteristics that are different from dysplasia of limb bone or skull. These characteristics are decisive in the diagnosis of the lesion.