增强核磁共振成像观察兔眼羟基磷灰石义眼座的纤维血管化过程研究

Studies on the hydroxyapatite orbital implants fibrovascularization with enhanced MRI

目的应用增强核磁共振(MRI)动态显像技术监测兔眼羟基磷灰石(HA)义眼座完成纤维血管化的时间,以证实MRI在评价HA义眼座纤维血管化程度方面的临床应用价值。方法健康清洁级新西兰大白兔30只,随机分为6组,均行单眼眼内容物剜出术及多孔巩膜壳内HA义眼座植入术,术后第1、2、3、4、5、6周进行增强MRI的相关检查并计算MRI图像中VE/VHA比值(VE为义眼座强化区体积,VHA为义眼座体积),于每周扫描完毕后处死1组兔,取出HA义眼座进行病理组织学的对照观察。结果兔眼HA植入后前4周间依次比较MRI图像中VE/VHA比值显著增加,而第4周后不再增加;兔眼HA病理检查也发现术后第4周全部植入HA义眼座均完成纤维血管化,HE染色可见致密的胶原纤维形成,以及内含红细胞的新生血管,并且无明显炎症细胞浸润。结论MRI可作为HA义眼座术后血管化程度监测的影像学依据。健康兔眼眶内植入直径12mm的HA义眼座在4周后可达到完全纤维血管化。

Objective To evaluate the clinical worth of application by investigating the characteristic of imaging in rabbits hydroxyapatite orbital implants fibrovascularization with MRI and exploring the relation between time and vascularization of the orbital implants. Methods 30 New Zealand white rabbits＇ right orbits with the same surgery procedure were divided randomly into 6 groups. At 1 week, and next six weeks postoperatively, imaging in rabbits hydroxyapatite orbital implants fibrovascularization were measured with MPd, and VE/VHA were calculated. One of groups＇ hydroxyapatite orbital implants were observed by HE stain. Results Before the 4th week, the average VE/VHA of the HA orbital implants in rabbits added up weekly, while the average VE/VHA of 5w and 6w are almost the same, all the HA orbital implants had accomplished fibrovascularization at the 4th week. Conclusion MRI is a way to detect hydroxyapatite orbital implants fibrovascularization; 12 mm HA orbital implants in rabbits had accomplished fibrovascularization at the 4th week.