羟基磷灰石眼眶植入物纤维血管化进程的MRI研究

MRI Study on the Hydroxyapatite Orbital Implant Fibrovascularization

目的采用MRI检查研究眼眶内植入羟基磷灰石(hydroxyapatite,HA)义眼台术后不同时期MRI表现。资料与方法回顾性分析28例眼眶内植入HA义眼台的MR表现,术后1～14个月至少行1次MR平扫及增强检查。义眼台纤维血管生长程度评价用Gd-DTPA增强SET1WI,按义眼台强化的程度和范围划分为Ⅰ～Ⅴ个等级。结果28例眼眶内植入HA义眼台,4例术后1个月,MR增强仅表现为义眼台边缘强化(Ⅰ级);5例术后2个月,其中4例表现为义眼台周围带状强化而中心未强化(Ⅱ级),1例表现为从义眼台周边至中心都有强化,但呈不均匀分布(Ⅲ级);5例术后3个月,均呈Ⅲ级表现;8例术后4个月病例中,有3例呈Ⅲ级表现,5例表现为整个义眼台较均匀明显强化或稍低(Ⅳ或Ⅴ级);6例术后5～14个月,4例呈Ⅲ级表现,2例为Ⅳ级表现。结论MRI增强扫描可直观、准确地评价义眼台血管化的程度和范围,为临床术后义眼台钻孔、置钉等提供有价值的信息。

Objective To investigate the characteristic of MRI in hydroxyapatite（HA） orbital implants and explore the relationship between the imaging and the vascularization at varying time intervals after implantation. Materials and Methods MR findings of 28 patients with hydroxyapatite（HA） orbital implants were analyzed retrospectively. They were performed with plain MR and enhanced MR at least one time from 1 to 14 months after HA orbital implant. According to the degree of enhancement, grade Ⅰ-Ⅴwas divided. Results MR images obtained 1 months after HA insertion in 4 patients had enhancement limited to the implant rim （Grade Ⅰ or less）. Of 5 patients undergoing MRI 2 months after HA placement, 4 had peripheral foci enhancement （ Grade Ⅱ ）, 1 had foci enhancement extending to the center of the implant （ Grade Ⅲ ）. 3 months after HA placement, all 5 patients had MR manifestations of Grade Ⅲ. 4 months after HA placement in the 8 patients, 3 had Grade Ⅲ, 5 had homogeneous enhancement throughout the implant （ Ⅳor Ⅴ ）. From 5 - 14 months after surgery in 6 patients, 2 had Grade Ⅳ, 4 had Grade Ⅲ. Conclusion Enhanced MR can directly evaluate the degree and extent of fibrovascularization in hydroxyapatite orbital implants, and provide useful information for treatment.