间接视神经损伤动物模型的研制.doc

间接视神经损伤动物模型的研制间接视神经损伤动物模型的研制更新日期：2010-11-13 王一周继红许立军马志中刘杰 【摘要】目的研制接近临床状态的间接视神经损伤动物模型。方法选日本大耳白兔,全麻后手术显露两侧眶上缘切迹和眶壁，咬除眶壁(深78 mm,宽6 mm),头放在致伤管下,将自制致伤卡头置于视神经孔上方眶板上,致伤球(45 g)从致伤管上端自由落下(管长2 m),击于致伤卡头,经骨板将力传递至视神经孔致伤神经,一侧不打击作对照。致伤后瞳孔散大固定，直接光反射消失为致伤成功。结果视神经损伤发生率76.7%，合并视神经孔骨折80，神经鞘膜出血53，鞘膜下血肿26.7%，视神经断裂10。结论本模型制作方法简单易行，成功率高，骨折及鞘膜下血肿发生率与临床视神经损伤时合并情况接近，有明确的神经损伤的临床特征，是目前最接近临床损伤特征的间接视神经损伤动物模型。 【关键词】视神经创伤和损伤模型 Preparation of Animal Model with Indirect Optic Nerve Injury WANG Yi, ZHOU Jihong, XU Lijun, et al. Dept. of Ophthalmology, Southwestern Hospital, Third Military Medical University, Chongqing 400038 【Abstract】ObjectiveVision is often seriously damaged in optic nerve injury. Most cases seen in clinics are indirect injuries. But animal model approaching the clinical features of indirect optic nerve injury has not been reported at home and abroad. Accordingly it is an urgent need to prepare an animal model for elucidation of the pathological course and for direction of clinical treatment of indirect optic nerve injury. Methods Under general anesthesia, the bilateral supra-orbital noches and orbital walls were surgically exposed. A rectangular gap on either side of orbital walls was made by excision of a portion of orbital lamina (7-8mm deep and 6 mm wide) from supra-orbital notch downwards to the optic foramen, so the underlying optic nerve was left intact. Then a self-made traumatic clamp was clamped on the upper margin of the remained orbital lamina above the optic foramen. A traumatic tube (length, 2m; inner diameter, 25mm) was perpendicalarly placed 25 mm above the traumatic clamp. Lastly, a rustless steel ball, (weight, 45 g; diameter, 22.25 mm) was dropped freely from the upper orifice of the traumatic tube and hit upon the upper surface of traumatic clamp. Occurrence of fixed pupil dilatation in company with loss of direct light reflex immediately after the struck were takenas criteria for a successful trauma. The optic nerve on the control side was not struck. ResultsIncidence of optic nerve injury was 76.7%. Gross anatomy, bone fractures of optic foramen 80%, hemorrhage of neurilemma 53%, subneurilemma hematoma 26% and separation of optic nerve 10%. Conclusions The method to prepare this model is simple, easy to use and of high success rate. The model, having incidence of bone fractures and subpial hematoma, similar to complications of clinical nerve injuries and definite clinical criteria for diagnosis of nerve injury, is therefore one of the most approaching clinical features of indirect optic nerve injury. 【Key words】 Optic nerveWounds and injuries Animal model 临床最常见的视神经损伤为间接损伤，目前对视神经损伤研究采用的致伤方法主要为钳夹、牵拉、冷冻，气囊压迫和切断等1-4，所造成的视神经损伤与临床间接视神经损伤特征存在较大差异，不能满足临床研究需要。为此，我们设计研制出接近临床状态的间接视神经损伤动物模型，为系统研究奠定基础。 材料与方法 一、 实验动物 日本纯种大耳白兔60只，体重2.02.5 kg，分为两组，每组30只。 二、 动物模型的制作 1模型制作方法之一：闭合式打击法。（1）致伤设备：装置如图1，为自由落体原理。主要有底座、工作台、可调滑动杆和打击锤4部分组成。致伤强度可调节。本实验致伤冲量1.30 kg*m。（2）动物模型制作：选取致伤眼眶上缘切迹内、后各0.5 cm为打击点，用龙胆紫标记，以标记点为中心用一相配的聚乙烯板（35 mm25 mm2 mm）保护，兔头置于工作台园孔窗下，打击点为中心点，用1.30 kg*m致伤冲量，对标记点打击，打击后的兔子喂养观察。 图1闭合式打击法致伤装置示意图 图2开放式打击法致伤装置示意图 2 模型制作方法之二：开放式打击法。（1）致伤设备：装置如图2，由以下几部分构成：致伤管（长2 m、内径25 mm)、致伤球(45 g)、致伤卡头(上方直径30 mm圆盘，下方为直径5 mm、长40 mm圆杆，杆的顶端为3 mm方形头，中央为宽1.5 mm、深1 mm槽），致伤冲量为重量乘以管的长度，本实验致伤冲量为0.09 kg*m。（2）动物模型制作：质量浓度为30 g/L的戊巴比妥钠（30 mg/kg）耳缘静脉注射麻醉。手术显露两侧的眶上缘切迹和眶壁。用咬骨钳经两侧眶上缘切迹处向视神经管方向咬除部分眶壁骨板（深78mm、宽6mm），保持硬脑膜和眶骨膜的完整性及视神经管的完整性。兔头放在致伤管下，将致伤卡头卡在一侧视神经孔上方的眶板上，调整卡头和兔头角度（兔头右侧斜15），使卡头与致伤管成一线，球从管上端自由落下击于卡头。对侧不打击作对照，缝合伤口，喂养观察。 3 视神经