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 observe the efficacy of vitreoretinal surgery in the treatment of early traumatized eyes with no light perception. Methods We performed vitreoretinal surgery on 17 eyes of early traumatized eyes with no light perception.The patients were followed up for 2～14 months. Results Retinal reattachment was achieved in 11 eyes after srugery.8 eyes got visual acuity better than light perception postoperatively.Visual acuities of 5 eyes were better than 0.05 and the best one reached to 0.2. Conclusion Timely vitreoretinal surgery is valuable to the early traumatized eyes with no light perception.Retinal reattachment is the most important thing for the treatment of this kind of cases. (Chin J Ocul Fundus Dis，2000，16：213-284)
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)
Objective To investigate the effect of long-term intraocular retention of domestic perfluorocarbon liquid (PFCL) on morphology and histology of ocular tissues. Methods A total of 18 New-Zealand rabbits were randomly divided into 3 experimental groups, whose left eyes underwent intraocular injection with 0.3, 0.6, and 1.0 ml PFCL, respectively. All of the right eyes of the rabbits were in the control group. The morphological, electrophysiological and histological changes of the ocular tissue were observed 4, 8, and 12 weeks after the injection. Results No clinically significant retinopathy but only mild morphological changes were found in group 1 and 2, while obvious morphological and histological changes were found in group 3. Mild morphological and histological changes were found in all of the rabbits 4-8 weeks after the injection while significant ones were found 8-12 weeks after the injection. The results of electroretinography indicated a statistically significant decline of amplitude of b wave in group 3. Conclusions Long-term intraocular retention of few PFCL may cause mild histological changes but not affect the clinical function. Plentiful PFCL remains in eyes may lead to toxic reaction to the ocular tissue. (Chin J Ocul Fundus Dis, 2006, 22: 128-130)
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)
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 effect of vitrectomy on traumatic retinal detachment combined with choroidal damage. Methods The data of 1075 traumatic eyes which underwent vitrectomy from 1995 to 2005 were retrospectively analyzed. Forty-one patients (41eyes, 3.8%) with different kinds of choroidal injuries, including traumatic retinal detachment combined with serous choroidal detachment, hemorrhagic choroidal detachment (including traum atic separation of choroid and sclera) or subretinal hemorrhage, underwent closed vitrectomy. The operative prognosis in different groups were analyzed statisti cally. Results The retina reattached in 38 eyes （92.7％）, in cluding 10 with the final visual acuity gt; 0.1（24.4％）；the visual acuity improved postoperatively in 29 (70.7％)，including 14 in subretinal hemorrhage group （87.5％, 14/16），12 in serous choroidal detachment group（75.0%, 12/16）and 3 in hemorrhagic choroidal detachment（33.3%, 3/9） (chi;2＝8.394, P＝0.015); amaurosis was found in 6 eyes, all of which were with hemorrhagic choroidal deta chment preoperatively. In 17 eyes with ocular hypotension, a persistent silicone oil tamponade was needed in 8（47.1％）, in which 5 were in the hemorrhagic choroidal detachement group (55.6％, 5/9). Conclusions Appropriate vitrectomy is helpful for traumatic retinal detachment combined with choroidal damage, and the operative prognosis of the patients combined with subretinal hemorrhage is good. The operative prognosis of hemorrhagic choroidal detachment is worse than that of the serous choroidal detachment. However, it doesnprime;t mean that all the hemorrhagic choroidal detachment eyes need ocular enucleation. The prognosis of eyes with severe traumatic choroidal detachment was poor, and the eyes are with ocular hypotension which needs a long-term silicone oil tamponade. (Chin J Ocul Fundus Dis, 2006, 22:295-298)
Purpose To explore the role of scanning laser tomography in the assessment of macular hole surgery. Methods Fifteen eyes of 14 patients with macular holes underwent scanning of their affected macular area using the Heidelberg retina tomograph (HRT). The significance of topographic changes postoperatively were determined in eleven eyes which received vitrectomy surgery. The scan field was set at 15°of the retina and the depth was set to 1.5 mm or 2.0 mm. All the measurements were taken for 3 times and the average value of the 3 measurements was used. Results The average hole area was (0.499±0.34) mm 2 and the maximal depth of the hole was (0.284±0.11) mm. Topographic difference analysis of the eleven eyes showed a significant reduction in the height of the retina after vitrectomy. The maximal depth of the hole was (0.063±0.04) mm postoperatively. Conclusion Scanning laser tomography provides an objective evaluation of the anatomic outcome of the macular hole surgery. (Chin J Ocul Fundus Dis, 2002, 18: 125-127)
OBJECTIVE:To verify the safe dose of cephradine in intravitreal injection. METHODS:After injecting different doses of cephradine(100mu;g,200mu;g,250mu;g,300mu;g,400mu;g)into vitreous cavity of different group of rabbits the activities of the retinal enzymes (SDH,LDH )on different time (Id,3d, 7d ) were determined respectively, and the histological and ultrastructural changes of retinas were also observed simuhaneously. RESULTS:The activity of rellnal SDH and LDH was found to be decreased gradually with tbe icreasing of the dosage of intravitreal cephradine. The activities of SDH and LDH were found in the lowest level on tile 3rd and lsl day,but they recover to normal levels on tile 7th day after intravitreal in}eetion in 100mu;g,200mu;g groups,and still lower tban normal in the other groups. Histologically,retinal edema was found both in 100mu;g and 200mu;g groups,but degradation of retinal cells,and loss of cones and rods were round in the 250mu;g, 300mu;g and 400mu;g groups. CONCLUSION: The safe dose of intravitreal injection of cepbradlnc is 200mu;g. （Chin J Ocul Fundus Dis,1997,13:139-142 ）
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）