Open Ocular Trauma Associated With Retinal Detachment Experimental Study On The Development Of Early Proliferative Vitreoretinopathy

Background:Open globe trauma refers to the destruction of the whole layer integrity of the eyeball wall and is an important part of the blindness in China.Severe open globe trauma often involves multiple intraocular tissues,and complex injury is often difficult to treat and having a poor prognosis.Correct treatment of open globe trauma is essential for achieving good anatomical and functional outcomes.Vitrectomy has become an important treatment for open globe trauma with retinal detachment.But the choice of surgical timing is controversial.In this experiment observation,we will reference other scholars findings to discuss the timing of the second stage vitreous surgery with open retinal detachment.Objections:To observe the occurrence and development of early proliferative retinopathy of severe ocular trauma with retinal detachment through animal experiments,and to provide reference for the choice of surgical timing in patients with severe ocular trauma with retinal detachment.Methods:The experimental animals(rabbits)were randomly divided into the experimental group which is made the open ocular trauma model with retinal detachment,and the control group which is made the open ocular trauma model without retinal detachment.The rabbit eye was using direct ophthalmoscope,slit lamp microscope and front mirror to observed.And the fundus was photographed.The PVR degree is graded by the Weiss rating method.The animals were killed 2,4,6,10,14 days after operation,the eyeball was removed,routine pathological sections and immunohistochemical(CK-7.GFAP)staining were carried out.Results:(1)On the second day after open globe trauma,We used direct ophthalmoscope to observe the vitreous cavity and retina of rabbit eye.The experimental group can be seen anterior chamber hemorrhage,about 1-2mm.The vitreous body is foggy and turbid,which did no observed proliferation.Retinal detachment was seen in the experimental group.In control group,the anterior chamber hemorrhage and vitreous exudation were similar to those in the experimental group.The retinal is flat.PVR grade between the two groups is 0.And we used light microscope to observe the pathological section,we find that a large number of lymphocytes and neutrophils infiltrated in the experimental group and the control group before retina,and scattered in most small inflammatory exudates.(2)On the fourth day after open globe injury,the experimental group and the control group had blood accumulation in the anterior chamber,and the vitreous exudation was absorbed to varying degrees.Neither group found significant fiber proliferation.Using light microscope we fund that the inflammatory infiltration and exudation in the two groups were less than those in the second day after injury.(3)On the sixth day after open globe trauma,the rabbit’s eyes of the experimental group all showed the formation of proliferative bundles of different thickness.In the control group,only a few rabbit eyes the formation of fine proliferative bundles.There were significant differences between the two groups(P<0.05)and the experimental group was higher than the control group.Neovascularization and fiber proliferation were observed in the experimental group before retina under light microscope,but not in the control group.(4)On the tenth day after open globe trauma,the rabbit eye of the experimental group could see the formation of small proliferative bands,and the control group could only see the formation of small proliferative bundles in the rabbit eye vitreous cavity.There were significant differences between the two groups(P<0.05)and the experimental group was higher than the control group.Fibrous proliferative membrane was formed in the experimental group before retina under light microscope.(5)On the forteenth day after open globe trauma,different thickness of proliferative strips were found in the vitreous cavity of the experimental group,and the proliferative bundles in the vitreous cavity of the control group did not develop into proliferative strips.There were significant differences between the two groups(P<0.05)and the experimental group was higher than the control group.Under the light microscope,fiber proliferation was seen in front of the retina in the experimental group,which is enclosing red blood cells,spindle cells and glial cells.(6)Immunohistochemistry showed that there were some cells which are marked by CK and GFAP in the experimental group,in the second day,forth day and sixth days after injury.But the number those cells was small,which could not fully confirm whether they were RPE cells or glial cells.Also it suggests that open eye trauma with retinal detachment may migrate RPE cells or glial cells in the early stages of injury.Conclusion:Severe eye trauma with retinal detachment showed obvious cell proliferation on the sixth day after open globe trauma.At the same time point,severe eye trauma with retinal detachment was more likely to occur than simple open eye trauma PVR.PVR grade in experimental group which has an open ocular trauma with retinal detachment was more serious than simple open globe trauma.This experiment can provide a reference for the choice of surgical timing for severe ocular trauma with retinal detachment.