Objective To observe the relationship between the suturing patterns to close the scleral incision and postoperative intraocular pressure (IOP) in 23G minimally invasive vitrectomy. Methods Eighty eyes of 80 patients with vitreoretinal diseases, who were treated with primary 23G minimally invasive vitrectomy, were enrolled in this prospective clinical study. Patients with poor closed scleral incision which need suturing were excluded from this study. The corrected visual acuity ranged from hand movement to 0.2. The IOP ranged from 7.9 to 19.8 mm Hg (1 mm Hg=0.133 kPa), with the mean of (13.9plusmn;1.8) mm Hg. The eyes were randomly divided into three groups: group A (20 eyes), suturing all three scleral puncture after vitrectomy; group B (20 eyes), suturing only two upper scleral puncture, but not the lower infusion puncture after vitrectomy; group C (40 eyes), no suturing for all 3 scleral puncture after vitrectomy. All patients underwent 23G vitrectomy only. The corrected visual acuity and IOP were observed after surgery. Results The corrected visual acuity were 0.1 -0.3, 0.2- 0.5, 0.3 -0.8 in one, seven and 14 days after surgery, respectively. No one in group A, B experienced hypotony in one, three, seven and 14 days after surgery. Thirteen (32.5%), five (12.5 %), two eyes (5.0%) in group C experienced hypotony in one, three and seven days after surgery. Seven eyes (17.5%) experienced severe hypotony (＜5 mm Hg) in 14 day after surgery in group C. The difference was statistically significant compared the incidence of hypotony in group C with group A, B respectively at different time points after surgery (chi;2= 16.82,P=0.007). The difference was statistically significant compared the incidence of hypotony in group C at different time points after surgery (chi;2=11.64,P=0.003). The difference was no significant compared the IOP between group A and B at different time points after surgery (F=1.618,P=0.205). Compared the IOP of group C to group A and B, the difference was statistically significant in one and three days after vitrectomy (F=9.351,P=0.000); but not statistically significant in seven and 14 days after vitrectomy(F=0.460,P=0.633). Conclusions Whether or not suturing the scleral punctures is closely related to postoperative hypotony in 23G vitrectomy. Suturing only the two upper scleral punctures can reduce the occurrence of postoperative hypotony.
Objective To observe the expression of related proteins of retina after subretinal implantation with inactive chips.Methods A total of 27 healthy adult New Zealand white rabbits were randomly divided into three groups: operation group (12 rabbits) in which the rabbits were implanted with inactive chips into the interspace beneath retina;shamoperation group (12 rabbits) in which the rabbits were implanted with inactive chips into the interspace beneath retina which was taken out immediately;the control group (3 rabbits). Animals were sacrified for immunohistological study 7,15,30 and 60 days after surgery.The rabbits in control group group were sacrified for immunohistological study after bred for 30 days.The expressions of glial fibrillary acidic protein (GFAP) and brain derived neurotrophic facor (BDNF) were observed.Results In operation group, the outer nulear layer of retina thinned, and the cells in the inner nulear layer was disorganized 7,15,and 30 days after the surgery;glial cells proliferated 60 days after surgery; the positive expression of BDNF and GFAP was more than that in the shamoperation and control group.In shamoperation group, the positive expression of BDNF and GFAP was more than that in the control group.No obvious difference of expression of BDNF and GFAP between each time point groups was found.Conclusions The expression of neroprotective related proteins increased after subretinal implantation with inactive chips suggests that limited neuroprotective effects might be led by the implantation.