Objective To explore the correlation between retinal extracellular edema and vitreous contraction in rabbits. Methods Seventeen pigmented rabbit models with retinal vein occlusion (RVO)was set up by laser photocoagulation. Retinal vascularity area was pathologically examined 1 month later.The vitreous gellength under the gravity condition and the percentage of its weight in the rabbits with extraeellular edema was observed. The mechanisms were investigated by Western immunoblotting of type II collagen.Results Extracellular edema was found in 13 experimental eyes 1 month after the formation of RVO (76.5~) with contracted vitreous gel and released watery liquid, and the a component of type II collagen was cross-linked together to form high-molecular-weight components of 1] and 7, which weakened the stability of collagen net structure.Conclusions Vitreous contraction and retinal extracellular edemawere correlated. The main reason may be the cross-links of vitreous collagen that damages the stability of collagen structure. (Chin J Ocul Fundus Dis，2004，20：2-32)
Objective To investigate the retinal toxicity and verify the safe dose of intravitreal injection of nonsteroid anti-inflamatory drug,diclofenac sodium.Methods Twenty-eight healthy adult white rabbits were divided at random into 7 groups and received in every right eye the intravitreal injection of a single dose of diclofenac sodium solution ranging from 0.4-0.1 mg/0.1ml respectively ,the left eyes were regarded as conreol ones.Before injection and on the 1st,3rd,7th,14th,21st,and 28th day after injection the electroretinography on both eyes was examined.On the 28th day after injection the retinas of two rabbits of every group were examined by using light microscopy.On the 10th and 30th day after injection the retinal tissues around the optic nerve sisk of two eyes from every group at random were tested by using transmission electron microscopy.Results The retio of amplitude ofb wave of electroretinography in 0.4mg and 0.5mg groups had no sighnificant difference from groups before injection,the retinal tissues showed no structural changes in light and ecectron microscopy examination.The ratio of amplitude ofb wave of photoptic electroretinogrphy in 0.6mg groups in the early stage after injection was markedly reduced（P＜0.05）and returned to that before injection with time,reversible change of the edematou retina was discovered.The ratio of amplitude of b wave of electroretinography in 0.7-1.0mg groups was distinctly descreaded after injection（P＜0.05 or P＜0.01）,the cells of all the retinal layer revealed apparent and irreversible damage.Conclusion The largest dose of safety of intravitreal diclofenac sodium should be not more than 0.6mg.The toxic effect of intravitreal diclofenac sodium on retina is concerned mostly to cones and rods.
Objective To evaluate the indications, effectiveness and complications of vitreoretinal surgery using the 25G transconjunctival sutureless vitrectomy system (TSV25G) under the topical anesthesia. Methods The clinical and follow-up data of 22 eyes of 22 patients undergone vitreo-retinal surgery using TSV25G under the topical anesthesia were retrospectively analyzed. All of the patients were monocular sickened, including idiopathic macular hole in 10 eyes, idiopathic macular pucker in 6, vitreoretinal traction syndrome in 4, and vitreous hemorrhage associated with branch retinal vein occlusion in 2. Peeling of epiretinal membrane and/or internal limiting membrane, intra ocular laser coagulation, air-fluid exchange and tamponiding of C3F8 were performed according to the condition of diseases. The postoperative follow-up was 1-11 months, with the mean duration of 6.4 months. The effect of analgesia, cooperation with the patients, operative effect and complications in and after the surgery were observed. Results The operations finished successfully in all of the eyes under the topical anesthesia. The operation duration ranged from 20 to 25 minutes with average of 22 minutes. The patients cooperated with the doctor well without any discomfort. Two days after the surgery, edema of the wounded conjunctiva was found, and recovered 7 days later. A light pigment dot on the surface of the sclera could be seen at the first month. The complic ations included transient increasing of intraocular pressure in 2 eyes, feather-like opacity of lens in 5 eyes, vitreous hemorrhage in 1 eye, and air-bleb under conjunctiva in 2 eyes. No other complications related with the cut were fo und. The macular hole closed in 9 eyes with idiopathic macular hole, and the other 1 had the smaller but not closed hole. Idiopathic macular pucker, vitreoretinal traction syndrome, and vitreous hemorrhage associated with branch retinal vein occlusion were cured successfully. Conclusions Vitreoretinal surgery using the TSV25G under the topical anesthesia has many advantages such as simple procedure, short operation time, micro-invasion, less complications and rapid revovery, and mainly serves simple manipulation in some simple diseases such as idiopathic macular hole, vitreo-retinal traction syndrome, and simple hemorrhage. (Chin J Ocul Fundus Dis，2004，20：133-136)
ObjectiveTo analyse the effect of vitrectomy in diagnosing and treating endogenous endophthalmitis. MethodsThe effects of treatment, prognosis and the final follow-up visual acuity of 22 patients (30 eyes) with endogenous endophthalmitis diagnosed in our hospital from Jan 2000 to Dec 2003 were retrospectively reviewed.ResultsIn 21 patients who underwent blood or vitreous body smear and culture, 18 (86%) had a positive result, including bacteria in 6, fungi in 11, and mixed infection in 1. In 16 patients who had complete follow-up data, successful vitrectomy were performed on 13 (81.3%) including 6 with functional success.ConclusionVitrectomy may improve the positive rate of culture and vision prognosis in patients with endogenous endophthalmitis.(Chin J Ocul Fundus Dis, 2005,21:142-144)
Objective To reveal the fibrillar network in vitreous and the effect of plasmin on this network.Methods 20 vitreous gels of freshly slaughtered pigs were divided into 2 groups, the gels in first group were digested by 3 Uplasmin (3 U/ml) at 37c for 24 hours respectively, the second group received the same PBS as control. After digestion, gels were fixed in neutral buffered formalin solution. Samples from vitreous base, cortex and the central region were observed by the technique of freeze etching electron microscopy.Results In vitreous collagen fibril network was in a three-dimensional array, collagen fibril density showed marked differences, central vitreous had the sparse fibril density, the cortex denser and the basal vitreous densest. After digestion by plasmin, the collagen fibrillar network was destructed.Conclusion Collagen fibrils in vitreous present spatial arrangement regularly, plasmin can lead to destruction of the fibrillar network.(Chin J Ocul Fundus Dis，2003，19：179-181)
Objective To review the distribution and shifting trends of cultured bacteria from the aqueous humor and the vitreous body. Methods A retrospective analysis on distribution of Gram′s stain, the distribution and change of isolates was performed in 522 specimens (aqueous humor,261 and vitreous body,261) of patients with suspected endophthalmitis during a 10-year period (1989-1998). Results The positive cultures were 119 (aqueous humor,44 and vitreous body,75) of 522 specimens. The average positive rate was 22.8%. Gram-positive cocci constituting 45.4%(54) of total isolates followed by Gram-negative bacilli,34.5%(41);Gram-positive bacilli, 20.2%(24). In the positive bacterial cultures, enterobacteriaceae was the most common isolate, 18.5%, and the next was micrococcus, 16.0%; coagulase-negative staphylococcus,12.6%; and pseudomonas,10.9%.Comparing the data from 1989 through 1993 with the data from 1994 through 1998, the frequency of Gram-positive cocci had no significant change, while the frequency of Gram-positive bacilli was decreased and the percentage of Gram′s-negative bacilli was increased. Conclusions Gram-positive cocci and Gram-negative bacilli are the predominant pathogens of bacterial endophthalmitis. The percentage of Gram′s-negative bacilli has increased for 5 years. It is very important to comprehend the distribution and shifting trends of these pathogenic bacteria for diagnosis, prevention and treatment of bacterial endophthalmitis. (Chin J Ocul Fundus Dis, 2002, 18: 104-105)
Objective To prepare a new glycoproteinopticin specific antibody and to explore the distribution of opticin in human eye. Methods Firstly, take the opticin specific antibody to compound a synthetic peptide chain（CLPRLPIGRFT）, and then get the opticin antibody. To verify the availability of antibody through the western blot for human vitreous extract, to test the distribution of opticin in human eye by immunohistochemistry. Results Through the western blot for human vitreous extract, we can see a band with wild range at molecular weight 45times;103~50 times;103. We find that opticin exact in retina, vitreous and non-pigmented epithelium of ciliary body which distributes along the collagen fibrils in vitreous. Conclusion The availability of the antibody was confirmed by western blot. Opticin are mainly in retina, vitreous and nonpigmented epithelium of ciliary body. Opticin distributes along the collagen fibrils which may be related to the stability of vitreous. （Chin J Ocul Fundus Dis，2008，24：286-288）
Objectivｅ To investigate the histopathologic charact eristic of the vitreous herniation out of sclerotomy site during vitrectomy. Methods Twenty specimens of tissues herniated at vitrectomy site were collected. The paraffin sections or fresh smears were stained with hematoxylineosin and examined under light microscope. The specimens were collected from the affected eyes with rhegmatogenous retinal detachment (9 cases), traumatic retinal detachment (1 case), miscellaneous vitreous hemorrhage (6 cases) and intraocular foreign body (4 cases). Results The herniated tissues were found to be retina in 4 cases, ciliary tissue in 1 case, retina and ciliary tissue in 1 case, uvea in 1 case, and hyaloid tissue in 13 cases. Conclusion There were not only vitreous, ciliary epithelial cells and pigment containe depithelia, but also ciliary body, retina and uvea in the prolapsed tissues of sclerotomy site, which might be related to the occurence of some clinical complications. (Chin J Ocul Fundus Dis,2001,17:99-101)
Purpose To evaluate the surgical effect of idiopathic macular hole (IMH)，with optical coherence tomography (OCT)． Methods To measure the diameter of holes and hole halos，the thickness of hole in edge，the changes of hole pattern in 19 cases (19 eyes) with IMH using OCT． Results By quantitatively measuring，OCT showed that after surgery the mean hole diameter lessened from （570．95plusmn;264．59 ）mu;m to （337．05plusmn;335．95）mu;m．The mean diameter of hole halo lessened from （1043．53plusmn;278．80）mu;m to （695．00plusmn;483．00）mu;m and the mean thickness of the hole edge thinned from （389．78plusmn;60．58）mu;m to （298．78plusmn;109．80）mu;m．In 17 eyes the holes become closed or reduced in size or the hole halo，and thinned in hole edge．The anatomic successful rate of the surgery is 89%． Conclusion OCT can objectively，accurately and effectively judge the anatomic effect of IMH surgery． (Chin J Ocul Fundus Dis，2000，16：71-138)