骨纤维结构不良继发动脉瘤样骨囊肿影像诊断

Imaging diagnosis of aneurysmal bone cyst secondary to fibrous dysplasia of bone

目的探讨CT与MRI对骨纤维结构不良继发动脉瘤样骨囊肿的诊断价值。方法对12例病理证实的骨纤维结构不良继发动脉瘤样骨囊肿CT及MRI资料进行回顾性分析。其中6例行CT检查,4例行MRI检查,另有2例分别行CT及MRI检查。结果单骨型11例,其中股骨5例,肱骨4例,腓骨1例及桡骨1例;多骨型1例,同时累及髋臼、坐骨支及股骨。在CT上可见病变不同程度膨胀,5例成单囊状或多囊状改变,3例成囊实性改变,实性部分呈磨玻璃样改变。在MRI上,6例均呈囊实性改变,实性部分在T1WI上呈均匀或不均匀低、等信号,在T2WI上呈均匀或不均匀低、等或高信号,增强扫描后呈轻或中度强化,其囊性部分呈T1WI低信号及T2WI高信号改变,骨皮质变薄,3例囊内见分隔,1例见液-液平面,增强扫描后仅有囊壁及囊内分隔强化。结论 MRI对骨纤维结构不良继发动脉瘤样骨囊肿诊断比CT有优势,但作出准确的术前诊断仍需结合X线或CT。

Objective To investigate the values of CT and MRI in diagnosis of aneurysmal bone cyst secondary to fibrous dysplasia of bone. Methods CT and MRI appearances of 12 cases were retrospectively analyzed, which were pathologically confirmed to be aneurysmal bone cyst secondary to fibrous dysplasia of bone. Among all patients, 6 cases underwent CT scanning, 4 cases were examined by MRI, another 2 cases underwent both CT scanning and MRI examination. Results In all cases, 11 cases were found being monostotic lesion, which included 5 cases involving in femurs, 4 cases involving in hu- merus, 1 case involving in fibula, and 1 case involving in radius. 1 case was found being polyostotic lesion with acetabular, sciatic branch and femur being involved. On CT, this lesions were shown bone swelling of different degree, 5 cases ap- peared single or multiple cysts, 3 cases appeared cysts or solid masses with solid part presenting ground glass opacity. 6 cases showed cysts and solid masses on MRI, the solid masses appeared homogeneous or heterogeneous signals with hy- pointensities or isointensities on T1 wigthed imaging and appaered homogeneous or heterogeneous signals with hypointensi- ties, isointensities or hyperintense on T2 wigthed imaging. On enhancement scanning, the solid masses were shown slight- ly or moderately enhancement. The cyst parts were shown hypointensities on T1 wigthed imaging and hyperintense on Tz wigthed imaging, cortical bones appaered thinning, 3 cases showed intracystic septa, 1 case showed fluid-fluid level in le- sion, enhancement of the capsule walls and septations were observed. Conclusion MRI has more advantages than CT in diagnosing of aneurysmal bone cyst secondary to fibrous dysplasia of bone, but it is still necessary to be combined with X- ray or CT for an accurate preoperative diagnosis.