低场磁共振在膝关节骨挫伤中的诊断价值

The Value of Low Field MRI in Diagnosis of the Bone Contusions of Knee Joint

目的:探讨低场磁共振在外伤性膝关节骨挫伤中的临床诊断价值。方法:对35例膝关节骨挫伤的患者X线平片、CT及低场强(0.35T)MR I检查资料进行回顾性分析。结果:本组35例X线平片均未见骨折征象,CT检查亦无明显骨折征象,仅见周围软组织肿胀和关节腔积液,MR I检查均显示有骨小梁骨折、骨髓水肿及小出血点的异常信号改变。在SE序列上表现为不规则片状T1W I低信号、T2W I高信号、STIR高亮信号的异常信号灶,所有病例骨皮质及骨轮廓均未发生变化,都有不同程度软组织损伤和关节腔积液。结论:低场强MR I能准确地显示不同部位骨挫伤的病变、范围和形态,清楚地显示膝关节骨挫伤的病变特点及严重程度,是检查膝关节骨挫伤有效的检查方法,为临床的诊治及预后评估提供有力的证据。

Objective： To investigate the value of low field MR/ in diagnosis of the bone contusions of knee joint. Methods： Imaging data of X-ray,CT and low field（0.35T） MR/ of 35 cases with bone contusions of knee joint were analyzed retrospectively. Results： No fracture of all patients was found on plain film. CT scanning showed there were only surrounding soft tissue swelling and liquid of articular capsule, and no obvious fracture. The result of MRI shows fractured trabecula, medullary edema and that the abnormal signal of small blood source has been altered. It shows anomalous sheet T1WI low signal, T2WI high signal, abnormal signal focus of STIR high bright singal in SE series. Neither disruption of cortical bone nor change of configuration was observed in all the cases, but there were soft tissue swelling and liquid of the knee joint cavity to varying degrees. Conclusion： Low field MRI had an ability to delineate accurately the location, extent and appearance of bone contusion, and accurately showed the features and assess the severity of the bone contusions of the knee joint. It is the best modality to evaluate the diagnosis of the bone contusions of the knee joint. Additional contusion and intemal derangements can be shown at the sametime. It provides more useful information for the treatment and prediction.