膝关节色素沉着绒毛结节性滑膜炎病理与MRI表现

目的探讨膝关节色素沉着绒毛结节滑膜炎(PVNS)的MRI表现与病理变化的关系.方法对21例膝关节PVNS进行回顾分析,并与手术病理结果对照.结果21例PVNS,20例为弥漫型,1例为局限型,均可见到数量不等的增生滑膜绒毛结节,多数在T1WI呈等或低信号,T2WI呈低信号,其中10例患者的部分结节在T1WI呈低信号,T2WI呈高信号.2例绒毛结节内可见脂肪组织;16例关节内外脂肪受累;18例均为程度不同软骨或骨受侵;膝关节均可见不同程度的积液;半月板及交叉韧带受累各1例.结论滑膜绒毛结节内含铁血黄素沉着导致T1WI等或低信号,T2WI低信号是膝关节PVNS特征性的MRI表现.MR检查对PVNS的诊断具有重要价值.

MRI manifestation and pathologic changes of pigmented villonodular synovitis of the knee joint

Objective To study the MRI features and the pathologic changes of pigmented villonodular synovitis (PVNS) of knee joint. Methods MRI in 21 cases with PVNS of the knee joint were retrospectively studied, and were compared with surgical and pathological findings. Results Twenty cases of PVNS were in diffuse form and one case was in localized form. Thickened villonodular were found in all cases, most of them were iso- to hypointense on T1WI, and hypointense on T2WI; hypointense on T1WI and hyperintense on T2WI in 10 cases. Fat signal within villonodular was found in 2 cases. Fat of the Knee joint was involved in 16 cases, and erosion of cartilage and bone was seen in18 cases. Effusion of joint was seen in all cases, while involvement of cruciate ligament and meniscus were found in 2 cases. Conclusion The iso- to hypointense on T1WI and hypointense on T2WI, which resulted from deposition of hemosiderin within villonodules, is the characteristic sign on MRI. MRI is a valuable technique in the diagnosis of PVNS.