The Experimental Study On Suprachoroidal Hemorrhage

Background and objectiveSuprachoroidal Expulsive hemorrhage is a very rare, but one of the most serious complications of intraoperative ophthalmopathy. the incidence varied from 0.03% ~ 6.2% . It not only happen to patients such as cataract,glaucoma and retina vitrousbody's operating but also to other ophthamopathy else, incloding penetrating corneal transplantation eye trauma and so on. The precise mechanism have not be clarified, up to now. The study on Suprachoroidal Expulsive haemorrhage is only limited in clinical case report, there is no related report in basic study, pathology change, prognosis and transformation, with regard to distinct periods at home and abroad.The primary cause is not success in seeking a suitable model.In order to investigate the clinical features and the development of freeing from affection of the different periods , try to find out the cause of the SEH and risk factors,probe the histopathology change ,provide the scientific and systematic theory basis for clinic, direct the clinical practice , raise us the recognition level, avoid this complication occurring , protect the patients vision try our best. Materials and MethodsAll fifteen health rabbits, weight 2.0-2.5kg of both sexes, were randomly divided into three groups.All animals were offered by Animal Department of medicine Shandong University (Jinan,China).The experiment was performed in accordance with Zanberman animal model of suprachoroidal explusive haemorrhage in research. ° All eyes were given 0.25% chloromycetin eyedrops for 3 days before surgery. The rabbits were anesthetized intramusculary with 25mg chlorpromazine hydrochloride and lOOmg ketamine hydrochloride. Topical anethesia with 0.5% dicaine eye drops was induced in the eyes immediately before surgery.All rabbits were ivdriped with 0.9%NS 250ml quickly in anesthesia, by tieing up ligation of vouticose veins, impeling the introocalar pressure rised rapidly, then simulating operativeincision, leading to intraocular pressure went down suddenly, bring out the model <> according to the distinct periods, we divided into three groups at randomly, including one week group, two weeks group,four weeks group.We performed the examination respectively ,the immediateiy after operation ,postoperation one week.two week .four week in terms of plan . the main indexes as follow:? The B-ultrasonographyStandardied echography of the B -scan ultrasonography can help establish an accurate diagnosis.Echography can determine the location and extent of expulsive hemorrhage, as well as determine the status of the retina and vitreous.Furthremore differentiation between hemorrhagic choridal detachment and serous choroidal effusion can be made oniy by B-scan.Through B-scan,we can follow up the assimilate status of liquefied gore and the atrophy situation of the eyeball.(DFVEP(flash Visual evoked potential)Aim at watching the eyesight of operated eye by incubation period length and wave amplitude lower.At last, the animal were killed respectively, after the operation one week, two weeks, four weekso We examed terms as follow(1) The SOD concentrations of retina tissue.It reflected retina damage condition in terms of biochemical metabolism.? General section preparation staining, as a whole,viewing the change of suprachoroidal explusive haemorrhage.(5) Electron microscopic observation on retina ultrastructure pathology change. Results(1) The improved model of SEH were successful in this experiment.(2) B-ultrasonography examination verified the condition of choroids effusion, choroidal hemorrhage, choroid retinodialysis. with the follow-up prolonging after operation, It showed absorption of heamorrhage progressively, but incidence of eyeball atrophy are significant different in 4W periods.(3) FVEP PI wave incubation period were lengthen lightiy and wave amplitude lower slightiy immediately after SHE,.There were no statistically significantly difference than normal control group o from 1W to 4W, LP1 and APlchanged evidently, there were significant different(p<0.01)o(4) SOD concentration in retina tissue were significantly lower than normal control group(P<0.01).(5) Under the light microscope, Bruch membrane and retinal pigmentary layer broke. Lots of RBC get into the upper cavity of choroids, subretinal cavity and vitreous body.(6) Electron microscopic observation indicated that the vascular occlusiono endothelialcel come off nuclearless and swollen> from dissolution to disappear in perichoroid, a lot of collagenous fibers heaped up, the rod outer segments connected loosely even breakdown with the rod inner segment., manyvacuoles and ecstatic endoplasmic reticulums mitochondrial crista decrease significantly, the retinal pigment epithelium put in disorder, pigment cell arrange scattered ? synapsis of nerve cell come off and head up pilus cilium coherence become rarefaction and breakdown, while time>2W.postoperative edema lighten gradually, there is proliferative change. Conclusion1 SEH Model of improved Zauberman's in this study was successful completely, It is a very good method for making model of SEH.2 SEH is the most serious disease, it leaded to damage to eyeball structure and vision, the change of histopathology^ physicology> biochemicology were all damage after SEH.3 The prevention of SEH is the most important, it need study on treating chance of SEH.