眶眼区钝挫性外伤的数值模拟分析

发布时间：2019-06-05 17:15

【摘要】：眼是人类重要的器官，人类90%的信息都是通过眼的采集而传入大脑的。目前，眼外伤已经成为影响视觉健康的主要原因之一。当碰撞物体大于眼眶口时，碰撞所造成的眶眼部损伤称为钝性外伤。损伤情况与碰撞的力量大小、方向有很大的关系，轻则引起眼睑软组织水肿、出血；眼球上的组织损伤；严重的导致眼眶壁的破裂、眼球的移位、运动功能损伤甚至眼球破裂等。研究外力对于眶眼区的作用、导致的损伤后果以及产生这些后果的力学机制，有重要的学术价值和临床意义。本文利用螺旋CT图像进行眶眼部各组织CT值的测量,通过经验公式获得了眶骨外侧壁、内侧壁、上壁和下壁等生物材料的材料常数。建立了同时过眼球中心和眼轴线的轴向断层与矢向断层的二维模型以及过视神经孔和眼眶内筛骨的轴向断层模型。二维模型虽简单，但有限元分析结果仍有一定意义。静力载荷施于眼睑软组织上，约束眶壁外边界线的前后向的位移，有限元分析的结果表明：1.眶内侧壁比眶外侧壁变形大；眶下壁较眶上壁变形大，这与临床资料的“内壁和下壁损伤最为多见，上壁和外壁较为少见”结果相符。2.眼球后半部分与视神经接触处的等效应力与等效应变相对较大，提示该处是较易受到损伤的地方。本文还以连续冠向断层图为基础，建立了眶眼区的三维模型，模型包括眶骨、眼球壳和眼内容物，以及眶内软组织。约束眶骨边界面的前后向位移，在眼睑和眶缘上施正压力，有限元分析结果也显示：1.眶内侧壁与眶下壁在钝性力作用下较其它两壁容易骨折；2.从眼球的变形情况分析，眼球上的易受损组织为虹膜根部、房角和晶状体等眼球前半部份的组织；3.眶内易受损组织还包括在眼球与眶内侧壁和下壁之间、控制眼球运动的下直肌、内直肌和下斜肌。这些都与临床资料相符，可以给临床医师提供一定参考，提示医师在检查病人时应该侧重检查的部位，以免漏诊外伤患者的伤情。
[Abstract]:The eye is an important organ of human beings, 90% of the information is transmitted to the brain through the collection of the eye. At present, eye trauma has become one of the main causes of visual health. When the colliding object is larger than the orbital orifice, the orbital injury caused by the collision is called blunt trauma. The injury is closely related to the strength and direction of the collision, but the soft tissue edema and bleeding of the eyelid are caused by the light injury, and the tissue damage on the eyeball is caused by the light injury of the soft tissue of the eyelid. It leads to the rupture of orbital wall, displacement of eyeball, injury of motor function and even rupture of eyeball. It is of great academic and clinical significance to study the effect of external force on orbital region, the consequences of injury and the mechanical mechanism of these consequences. In this paper, the CT values of orbital tissues were measured by spiral CT images, and the material constant of biomaterials such as lateral wall, medial wall, superior wall and inferior wall of orbital bone were obtained by empirical formula. A two-dimensional model of axial and sagittal tomography passing through the center of the eye and the axis of the eye, as well as the axial tomography model of the optic nerve foramen and the ethmoid bone in the orbit, were established. Although the two-dimensional model is simple, the finite element analysis results still have certain significance. The static load applied to the soft tissue of eyelid restricts the forward and backward displacement of the outer boundary line of orbital wall. The results of finite element analysis show that: 1. The deformation of the medial wall of the orbit is larger than that of the lateral wall of the orbit, and the deformation of the suborbital wall is larger than that of the supraorbital wall, which is consistent with the results of "the injury of the inner wall and the inferior wall is the most common, and the upper wall and the outer wall are rare". The equivalent stress and equivalent effect at the contact between the posterior part of the eyeball and the optic nerve became relatively large, suggesting that the posterior part of the eyeball was more vulnerable to injury. On the basis of continuous crown tomography, a three-dimensional model of orbital region was established, which included orbital bone, eyeball shell and eye contents, as well as orbital soft tissue. The forward and backward displacement of the orbital edge interface is constrained, and the positive pressure is applied to the eyelid and orbital margin. The results of finite element analysis also show that: 1. The medial orbital wall and the suborbital wall were more likely to fracture than the other two walls under the action of blunt force. From the analysis of the deformation of the eyeball, the vulnerable tissues on the eyeball were the iris root, the angle of the chamber and the anterior part of the lens. Orbital vulnerable tissue also includes the inferior rectus muscle, internal rectus muscle and inferior oblique muscle, which control the movement of the eyeball between the eyeball and the medial and inferior walls of the orbit. These are consistent with the clinical data, which can provide some reference for clinicians, suggesting that doctors should pay attention to the location of examination when examining patients, so as not to miss the injury of trauma patients.
【学位授予单位】：福州大学
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：R779.1

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