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Objective: To evaluate the efficacy of 5-fluorouracil polyactic acid microsphere in prevention of proliferative vitreoretinopathy (PVR)., Methods: 5-fluorouracil polyactic acid microsphere or 5-fluorouracil were used to implant into rabbits vitreous cavity. 48 healthy rabbits were divided into 3 groups: rabbits in Group 1 received implantation of 5-fluorouracil polyactic acid microsphere; rabbits Group 2 served as polyactic acid microsphere control; rabbits in Group 3 received only 5-fluorouracil powder. Macrophages were injected into vitreous cavity of rabbit to induce PVR. 0.2 ml BSS containing 25 mg microsphere with 2.6 mg 5-fluorouracil was injected into vitreous cavity of two eyes in Group 1. 0.2 ml BSS containing 25 mg microsphere without medicine and 0.2 ml BSS containing 2.6 mg 5-fluorouracil were injected into rabbits vitreous cavity in Group 2 and 3 respectively, Drug content in aqueous humor was measured regularly. Release feature of 5-fluorouracil polyactic acid microsphere in vivo was observed. The efficacy of the inhibition of PVR was evaluated according to Ryan's grade of proliferative vitreoretinopathy., Results: The releasing time of 5-fluorouracil polyactic acid microsphere was much longer than 5-fluorouracil powder. Its half life T(1/2) was 379.05 h with low clearance rate. The attack rate of retinal detachment in Group 2 was 62.5% and 71.9% on the 21st and 28th day respectively. The attack rate of retinal detachment in Group 3 was 64.3% and 78.6% whereas that of Group 1 was 13.3% and 13.3% on the 21st and 28th day. There was statistical difference in retinal detachment rate in Group 1 and 2 or 3 (P < 0.01). No differences was found in retinal detachment ration in Group 2 and 3 (P > 0.05)., Conclusion: Implantation of 5-fluorouracil polyactic acid microsphere into vitreous cavity can effectively prevent proliferative vitreoretinopathy induced by macrophages in rabbit model.

Purpose: To probe the results of trabeculectomy with human amniotic membrane (HAM) or mitomycin(MMC) in the treatment of glaucoma., Methods: In a randomized control clinical trial, 48 eyes of 28 glaucoma patients were divided into two groups, each group has 24 eyes, and each group was divided into two sub-groups according to the age. The former was underwent trabeculectomy with HAM transplanted, the later was administrated intra operatively with MMC, 0.2-0.4mg/ml, for 2-4 minutes, the follow-up was 6 months., Results: The operation success rate of both groups was higher than the standard trabeculectomy, and the difference between the two groups was not significant. Complications induced by HAM were mainly shallow anterior chamber, whereas by MMC were thin wall bleb, bleb leaking, persistent hypotony and hypotonous maculopathy., Conclusion: Application properly HAM or MMC can improved the operation success rate, maintain the functional bleb long time and decreased the complications.

Purpose: To investigate the anti-fibroplastic effect of the preserved human amniotic membrane by transplanting on animals in glaucomatous surgery., Methods: Trabeculectomy were performed on 48 eyes of 24 rabbits which were divided into 3 groups: group A was treated with the amniotic transplantation under sclerotic flap, group B was performed trabeculectomy using MMC (0.25mg/ml) under sclerotic flap and group C played the role of control which had surgery only. postoperative examinations including the intraocular pressure (IOP) , filtering bleb, reaction of the anterior chamber and complications were performed on 1, 2, 3, 7, 14, 28, 60 days after surgery respectively. A rabbit selected randomly in the three groups was killed in 1, 2, 3, 4, 8 week after operation and extirpated the eyeball to observe the time of decomposition of the amniotic membrane in pathologic tissue slice, counted the number of fibroblast and inflammatory cells with computer and compare their difference., Results: There were not significant difference of IOP among the three groups except observed on the first day after operations (P > 0.05); Comparing with group B and group C, the complications of group A ( amniotic membrane) didn't increased. The duration of the existing time of the filtering blebs was about 1 month. The decomposed time of the amniotic membrane was about 3-4 weeks, after 4 weeks it was substituted by fibroblast and inflammatory cells. The number of fibroblast counted by computer showed significant difference between group A (0.0205+/-0.01235) and group C (0.0673+/-0.03830) (P=0.017 < 0.05), and no obvious difference with group B. The inflammatory cells of group A (0.4402+/-0.1708) increased greatly in comparison with group B (0.0407+/-0213) and group C (0.0294+/-08876); (t=5.67, P=0.002 < 0.05, t=4.81, P=0.004 < 0.05 respectively)., Conclusion: The decomposed time of the amniotic membrane is about 3-4 weeks in trabeculectomy. Amniotic membrane has a restraint effect on fibroblast and it can enhance the effect of surgery to lower the IOP in trabeculectomy as well as has less complication. The inflammation reaction in the operation area of the group A is heavier than the others which may be caused by repellent reaction between different species.

Objective: To study the proliferating status of pterygium and the drug's influence on it., Method: Fifty four patients with pterygium were randomly assigned into three groups: Before the surgical excision of the pterygium, group 1 (18 cases) had received no drug, group 2 (16 cases) received local dexamethasone treatment, and group 3 (20 cases), local homoharringtonine and dexamethasone treatment. The immunohistochemical study on proliferating cell nuclear antigen (PCNA) was performed on the surgical specimens of the pterygium., Result: The PCNA positive rate was (11.53 +/- 3.62)% in the untreated group, (10.28 +/- 4.18)% in the dexamethasone group (P > 0.05), and (5.59 +/- 3.82)% in the homoharringtonine and dexamethasone group (P < 0.01). The PCNA positive rate was higher in the younger patients (< 60 years) with progressive type of the disease than that in the elder patients (>or= 60 years) with quiet type., Conclusions: There are cell proliferation and PCNA expression in pterygium. The homoharringtonine and dexamethasone local injection before the excision of pterygium can effectively decrease the PCNA expression and recurrence rate of pterygium. Local injection of dexamethasone before surgical excision has no influence on the PCNA expression of pterygium.

Objective: To report four acute lymphoblastic leukemia(ALL) patients who developed tumor lysis syndrome(TLS) after initial chemotherapy., Methods: The clinical features and blood biochemical changes of four patients with TLS were analysed., Results: TLS was characterized by hyperuricemia, hyperkalemia, hyperphosphatemia and hypocalcemia. Three cases had renal dysfunction and the other died of acute renal failure. After allopurinol therapy and alkalinization of urine, the blood biochemical parameter became normalization in all the three cases., Conclusions: TLS can be effectively controlled by early recognition and administration of allopurinol therapy and alkalinization of urine.

Objective: A prospective randomized and placebo-controlled study was performed to evaluate the effect and toxicity of injectable bioerodible polymer with 5-fluorouracil (5-Fu) on the filtration surgery in rabbits., Methods: Posterior lip sclerectomies were performed on both eyes of 23 rabbits. Injectable bioerodible polymer impregnated with 2.5% 5-Fu 10 mg was injected subconjunctivally in 16 eyes, and 2.5% 5-Fu 10 mg was injected subconjunctivally in 14 eyes every other day for three times in the first week and every two days for three times in the second week post-operatively. Another 16 eyes received the drug-free polymer after surgery and served as controls., Results: The bleb in the eyes treated with drug-free polymer failed in the postoperative 7 days and the bleb in the eyes treated with 5-Fu injection failed in 20-30 days, while the bleb in the eyes treated with 5-Fu polymer remained successful throughout the experimental period. From 7 to 30 postoperative days, the rate of scleral fistula occlusion was 6.7% in the eyes treated with 5-Fu polymer, 41.7% in the eyes treated with 5-Fu injection and 100% in the eyes treated with drug-free polymer. Corneal epithelial defects appeared in 3 eyes treated with 5-Fu polymer, in 8 eyes treated with 5-Fu injection and in 2 eyes treated with drug-free polymer., Conclusion: Injectable bioerodible polymer with 5-Fu may significantly prevent bleb scarring and subsequent blockage of the filtering tract, enhance success rate of filtering surgery in rabbits and reduce the toxicity of 5-Fu. This drug delivery system has considerable value for clinical use.

To improve the function of filtering blebs after trabeculectomy, we divided randomly 44 patients (60 eyes) with moderate or late glaucoma into mitomycin C and control groups (30 eyes per group). Two small surgical sponges were soaked with 0.2 mg.ml-1 mitomycin C solution. One sponge was put on the top of the superficial scleral flap, the other was placed underneath the scleral flap and contacted with the bed of the scleral flap. After 5 minutes the wound was then irrigated with normal saline. All patients were followed up from 1 to 12 months (7.9 +/- 4.0 months). We found that: (1) functional filtering blebs were 92.9% in the mitomycin C group and 55.2% in the control group (P < 0.01), (2) the decreasing percentage of intraocular pressure (IOP) in the mitomycin C group was much more than that in the control group (P < 0.05), (3) the successful rates of the operation in MMC group were higher than that of the control group, and the visual field was effectively maintained in MMC group.

To prevent the cicatrization of filtering blebs after glaucoma filtering surgery, subconjunctival injections of low dosage homoharringtonine were administered to 22 glaucomatous eyes (20 patients) postoperatively. The percentage of functional filtering blebs was 90.9% and the mean postoperative IOP was 2.04 +/- 0.68 kPa (1 kPa = 7.5 mmHg). In comparison with the control group, the differences were very significant (P < or = 0.01). The results suggest that the toxicity of low dosage of homoharringtonine be very low, it inhibit fibroblast proliferation and play important roles in the formation of the functional filtering blebs and elevation of the success rate of filtration operation.