Objective To summarize the visual outcome of patients with severe ocular trauma treated with vitreous surgery. Methods Clinical data of 188(191 eyes) with severe ocular trauma treated with vitreous surgery in a period from November 1996 to April 1998 were analysed retrospectively. Results The study included penetrating injury in 56 eyes, foreign bodies in the posterior segment in 70 eyes, blunt injury in 41 eyes , and globe rupture in 24 eyes. Main complications included endophthalmitis in 35 eyes, choroidal bleeding in 20 eyes, retinal detachment in 60 eyes, and vitreous hemorrhage in 97 eyes. Post-opera-tively, out of 188 eyes, except for 3 of patients too young to examine, visual acuity improved in 133(70.7%), including 85(45.2%) with visal acuity 0.02-1.0, 46(24.5%) remained unchanged; and 9(4.8%) had worse vision. Among 34 with no-light-perception, 12 had light-perception or over. Conclusion A majority of severe trauma eyes can be salvaged with considerable visual recovery after adequate and timely vitreous surgery. (Chin J Ocul Fundus Dis,1999,15:4-6)
Objective To evaluate the curative effects of vitreoctomy or simple scleral buckling on retinal multiple-tear detachment associated with tracted anterior flap. Methods The clinical data of 89 eyes in 89 patients with retinal multiple-tear detachment associated with tracted anterior flap diagnosed in Jan, 1999-Jan, 2002 were retrospectively analyzed. In the 89 patients, 41 had undergone vitreoctomy and 48 had undergone scleral buckling without vitrectomy. In the duration of 2- to 36-month follow-up with the mean of (11.02±7.90) months, visual acuity, retinal reattached rate and postoperative complication were examined and the results in the 2 groups were compared. Results In 41 eyes underwent vitreocotmy, successful reattachment was found in 38 (92.7% ); visual acuity increased in 33 (80.5%), didn′t change in 6 (14.6%), and decreased in 2 (4.9%); leakage of flocculent membrane in anterior chamber occured was found in 2 (4.9%), complicated cataract in 3 (7.3%),and severe proliferative vitreoretinopathy (PVR) in 3 (7.3%). In 48 eyes underwent scleral buckling, 41 (85.4%) had success reattachment; visual acuity increased in 36 (75.0%), didn′t change in 4 (8.3%), and decreased in 8 (16.7%); leakage of flocculent membrane in anterior chamber was found in 6 (12.5%), complicated cataract in 9 (18.8 %), and severe PVR in 8 (16.7%). Conclusion There isn′t any difference of the success rate of the surgery between vitrectomy and scleral buckling for retinal multiple-tear detachment associated with tracted anterior flap.The better visual acuity and less complications are found in the vitrectomy gro up than those in the scleral buckling group. (Chin J Ocul Fundus Dis，2004，20：209-211)
Objective To observe the therapeutic effect of poly tetrahydrofurfuryl co-lactic acid(copolymer C4) as the biodegradable vitreous substitutes on rhegmatogenous retinal detachment.Methods Vitreoretinal surgery with copolymer C4 tamponades was performed on 32 pigmented rabbits (64eyes) with rhegmatogenous retinal detachment. The rate of reattached retina and the post operative cornplications were observed.Results Three months after the operation, reattached retina was found in 96. 4%, glaucoma in 5.5%, cataract in 10.9%, and copolymer emulsion in 10.2% of all the eyes.Conclusion copolymer C4 may withstand the retinal tear effectively for 3 months, and can be a valuable vitreous substitutes. (Chin J Ocul Fundus Dis，2004，20：27-28)
Objective To analyze the clinical risk factors of the occurrence of severe proliferative vitreoretinopathy (PVR) after scleral reattachment surgery. Methods A total of 4031 eyes of 4031 consecutive patients with reghmatogenous retinal detachment (RRD) and PVR (grade C1 or less), on whom the scleral buckling was performed, were retrospectively studied. Twenty-two clinical charac teristics of the patients (including the ocular tension, condition of lens and vitreous, characte ristics of retinal detachment, whether or not with choroidal detachment, et al) were recorded.In 4031 patients, 2660 were followed up for more than 3 months, and 72 (in PVR group) of the 2660 patients underwent the second surgery (vitre oretinal surgery) because of the occurrence of postoperative seve re PVR; in the other 2588 patients, 72 (72 eyes) with retinal reattachment for more than 3 months were selected randomly as the control. The data were analyzed in SPSS (10.0) software. Results Logistic regression analysis revealed that the significant risk factors for PVR were incomplete posterior vitreous detachment ( P＜0.001), intraocular pressure lt;7 mm Hg（1 mm Hg=0.133 kPa, P＜0.002）, and large retinal tear (gt;2 DD,P＜0.005). Conclusion Incomplete posterior vitreous detachment, intraocular pressure lt;7 mm Hg and large retinal tear of the patient with RRD may be the major risk factors for PVR. (Chin J Ocul Fundus Dis，2003，19：141-143)
Objective To examine the expression of proliferating cell nuclear antigen (PCNA) of retinal pigment epithelial (RPE) cells, thus assessing the role of mechanism of contact inhibition playing in the process of experimental retinal detachment and reattachemnt.Methods Retinal detachment was produced in 72 cats by subretinal injection of 0.25% solution of healon through a micropipette three weeks after extracapsular lens extraction and vitrectomy. Some of the detached retinae were reattached 24 hours later. At different time, the cats were killed and eye globes were fixed and embeded in paraffin. Histologic sections were processed for immunohistochemistry examination using an antibody to detect PCNA protein. Labeled RPE cells were identified, and the proliferation was quantified in detached and un-detached retinae of detachment group, and also in reattached retinae of reattachment group. The comparsion of PCNA-labeled RPE cells in different groups were analyzed by ANOVA. Results In detached regions of detachment group, PCNA-expression of RPE cells occured within 24 hours, and reached a maximum after 5-6 days, then gradually declined to barely detectable levels after 20 days. Similar tendency was found in reattached retinae, but the number of PCNA-labeled RPE cells was obviously small. Fewer PCNA-labeled RPE cells were found in regions of un-detached retinae in detachment group. The difference of these three groups was significant.Conclusion Proliferation of RPE cells is induced when they lose contact with neural retina, but inhibited after neural retina reattached to RPE cells. It suggests that the mechanism of contact inhibition plays a role in the proliferative process after retinal detachment and reattachment. (Chin J Ocul Fundus Dis，2003，19：20-23)
Objective To investigate the technique of drain-air, cryotherapy, and explant (DACE) of operation for superior bullous retinal detachment (SBRD).Methods In the DACE procedure, drainage and air or balanced salt soultion (BSS) injection were carried out first, with the intention of flattening the retina before localization of retinal hole, cryotherapy out of choroid and scleral buckling.Results In 42 SBRD eyes, 40 underwent the operation with DACE technique. In 23 eyes injected with BSS instead of air, 5 should be injected air due to no avail for flattening deeply retinal detachment, and 1 needed scleral buckling due to new retinal tear after DACE procedure two weeks. During the follow-up, all retinae attached. Conclusions The DACE technique is very useful and effective in upper ballooned retinal detachment due to single hole or breaks localized in small area between the 10 and 2 o′clock meridiant. BSS instead of air injection can eliminate the difficulty of observation of retinal breaks from the presence of air in some cases. (Chin J Ocul Fundus Dis，2003，19：11-13)
Objective To investigate the correlation factors of macular pucker after vitrectomy, and compare the surgical effect between secondary and idiopathic epiretinal macular membrane.Methods A study of 26 consecutive patients (26 eyes), in which 18 were diagnosed as secondary epiretinal macular membranes and 8 as idiopathic epiretinal macular membranes, underwent par plana vitrectomy, vitreous cortex separation, and peeling off of the epiretinal macular membrane. The follow-up period was within 3~12 months. Preoperative and postoperative examination included visual acuity, fundus photography, and optical coherence tomography in some patients.Results Among the 18 patients with secondary epiretinal macular membranes, 9 (50.0%) were related to vitreous surgery. There was statistical difference between cryoretinopexy to giant retinal tear and endolaser （χ2=12.24，P＜0.05). Eleven patients (61.1%) with secondary epiretinal macular membranes were related to vitreous hemorrhage before or after surgery. We found all macular puckers removed in post-operative examination. The metamorphopsia disappears after 3 months in 8 patients (30.8%), and the situation was better in 18 (69.2%). The visual acuity of the patients with idiopathic epiretinal macular membranes improved 3 lines averagely after operation, and the best-corrected visual acuity was 0.8. The patients with secondary epiretinal macular membranes improved 1.33 lines averagely after vitreous and retinal surgery, and the best-corrected visual acuity was 0.6. Conclusion Cryoretinopexy to giant retinal tear and vitreous hemorrhage before or after surgery are the risk factors of secondary epiretinal macular membranes. Idiopathic epiretinal macular membrane has a better surgical effect than secondary one. (Chin J Ocul Fundus Dis，2003，19：90-92)
Objective To evaluate the therapeutic effect of encircling scleral buckling surgery in rhegmatogenous retinal detachement (RRD) with vitrectomy. Methods The records of a series of 118 consecutive patients with RRD undergone encircling scleral buckling surgery and vitrectomy between 1995-1999 were reviewed. All of the patients underwent an onece vitrectomy, and they consisted of with encircling scleral buckling group and without encircling scleral buckling group. The difference of rate of retinal reattachment, and the relationship between the reattachment rate and the grade of PVR, position of retinal tear and the different intraocular tamponade substitute in both groups were analysed and compared. The average follow-up period was 6.5 mons (1.5 mons-3 ys). Results The rate of retinal reattachment in this series of 118 cases was 81.4% (96/118) in which the encircling scleral buckling group accounted for 44.7% and the group without encircling scleral buckling accounted for 55.3%. There was no statistical difference of rate of retinal reattachment between both groups with PVR C, different intraocular tamponade and various positions of retinal tears, while the rate of retinal reattachment in cases of PVR D and retinal tears posterior to equator in group without encircling scleral buckling was significanthy higher than that in encircling scleral buckling group (Plt;0.05). Conclusion The encircling scleral buckling procedure may be unprofitable in increasing the rate of retinal reattachment in vitrectomy for RRD. (Chin J Ocul Fundus Dis, 2002, 18: 212-214)