Objective To observe the related complications of 23G pars plana vitrectomy (PPV). Methods One hundred and fifteen patients who underwent 23G PPV were enrolled in this study. There were 98 patients (65.3%) with macular diseases, 46 patients (30.7%) with proliferative diabetic retinopathy, four patients (2.7%) with vitreous hemorrhage, one patient (0.7%) with rhegmatogenous retinal detachment, and lens nucleus falling off in cataract surgery in one patient (0.7%). Among 98 patients with macular diseases, 21 patients (21.4%) underwent topical anesthesia, 77 patients (78.6%) underwent retrobulbar anesthesia. DORC "twostep method" was performed in three patients, and Alcon 23G PPV "onestep method" was performed in 147 patients. The operation times ranged from 20 to 100 minutes, with a mean of (51.1±18.9) minutes. The follow-up ranged from three to 12 months. The intraoperative and postoperative complications were observed. Results Intraoperative complications was found in seven patients (4.7%), which included iatrogenic retinal breaks in one patient (0.7%), macular damage in one patient (0.7%), suprachoroidal perfusion in one patient (0.7%), puncture leakage and closure incision in two patients (1.3%), vitreous hemorrhage in one patient (0.7%) and stopper broken off in cannula in one patient (0.7%). Postoperative complications was found in 34 patients (22.7%), which including retinal detachment in one patient (0.7%), vitreous hemorrhage in three patients (2.0%), cataract in three patient (2.0%), intraocular pressure ＜10 mm Hg（1 mm Hg=0.133 kPa） in 20 patient (13.3%), and transient ocular hypertension in seven patients (4.7%). After treatment there was no complication associated with surgery. Conclusion Intraoperative complications related to incision and transient hypotony are mainly complications of 23G PPV.
Objective To observe the incidence of hypotony and its risk factors in the early stage after 23-gauge sutureless microincisional vitrectomy. Methods A retrospective case series. Seventy patients (70 eyes) who had undergone 23-gauge sutureless microincisional vitrectomy were enrolled. There were 41 phakic eyes, 29 eyes with intraocular lens; 68 eyes with a single surgical procedure and 2 eyes with a second surgical procedure; 34 eyes with BSS tamponade and 36 with gas tamponade. Intraocular pressure (IOP) was measured by non-contact tonometry. Hypotony was defined as an IOP of 5 mm Hg (1 mm Hg=0.133 kPa ) or less. The incidence of hypotony and other complications at postoperative day 1, 3 and 7 were observed. The influence of age, sex, side of operation, type of tamponade, status of lens, surgical time on postoperative hypotony was analyzed. Results Hypotony was found in 8 eyes (11.4%) on postoperative day 1 and recovered spontaneously on postoperative day 3. There were no significant differences comparing age (t=1.12), sex (chi;2=2.23) and side of operation (chi;2=2.01) between patients with hypotony and those without it. The patients with hypotony suffered longer surgical time than that of those without hypotony (chi;2=5.48,P＜0.05). The incidence of hypotony in eyes with gas tamponade was significantly lower than that in eyes with BSS tamponade (chi;2=5.48,P＜0.05). The incidence of hypotony in eyes with phakic eyes was lower than that in eyes with intraocular lens (chi;2=4.20,P＜0.05). Hypotony was encountered in the 2 re-operated eyes. Choriodal folds were encountered in 2 eyes, but there was no other complication in other eyes. Conclusions A transient hypotony occurs commonly in first 3 days after 23-gauge sutureless microincisional vitrectomy. Hypotony was significantly influenced by type of tamponade, reoperation and intraoperative lens status.
Objective To investigate the refractive shift after combined surgery （phacoemulsification, intraocular lens implantation and vitrectomy） by comparing the difference between the predictive and postoperative refractive power.Methods The clinical data of 44 patients (48 eyes) underwent combined surgery (combined group) and 30 patients (50 eyes) underwent cataract surgery (cataract group) were retrospective analyzed. Combined group was further divided into two sub-groups by the kind of tamponade: balanced salt solution group and gas group. Before surgery, axial length and corneal curvature were measured, and the predictive spherical equivalent (PSE) was calculated. Axial length, corneal curvature and actual spherical equivalent (ASE) were measured in six months after surgery. The differences between PSE and ASE were compared between combined group and cataract group, balanced salt solution group and gas group.Results In combined group,the mean PSE was (-0.10plusmn;0.42) D and ASE was（-1.00plusmn;1.10） D, and the difference was significant（t=6.687, P＜0.05）. Patients underwent combined surgery showed a statistically significant myopic shift compared with those underwent simple cataract surgery （t=-3.792,P＜0.05）, the refractive shift of balanced salt solution group and gas group were (-0.76plusmn;0.89） and （-1.19plusmn;0.94） D respectively, and there was no significant difference（t=-1.530,P＞0.05）.Conclusion Combined surgery of phacoemulsification and vitrectomy tends to shift the actual refractive status to myopia.
Intravitreal injections of anti-vascular endothelial growth factor (anti-VEGF) drugs, including monoclonal antibodies (such as bevacizumab and ranibizumab) and fusion protein agents (such as aflibercept and conbercept) have been proven to be effective in the treatment of wet age-related macular degeneration (wAMD). However, there are still some patients with poor efficacy, such as no response to initial treatment or poor response, and even relapse during the course of treatment. In view of the different targets and molecular characteristics of anti-VEGF drugs, the switch of anti-VEGF drugs and the adjustment of delivery pattern, dosages and intervals have been the strategies to cope with the poor efficacy in clinic. However, there are some differences in the results of current studies. Overall, the recovery of retinal anatomical outcome achieves more benefits, and it is relatively difficult to improve visual acuity. To determine which regimen would get the biggest benefits, a large number of randomized controlled clinical trials and long study period will be needed.
Accurate collection and preservation of vitreous and retina-related tissue specimens is the basis for clinical diagnosis and rigorous basic research. The clinical uses of vitreous specimens include microbial culture, cytological detection, detection of degenerative diseases, PCR analysis, and cytological detection of cell morphology. The experimental research uses include DNA gene analysis, protein quantitative analysis, metabolite examination, RNA content quantitative analysis, cytokine determination and so on. Retinal specimens collecting was mainly used for PCR analysis of retinal proliferative membrane, immunohistochemical staining, immunofluorescence examination, microvascular density evaluation, cell isolation and culture, etc. Understanding the collection of vitreoretinal surgical specimens and the application of relevant detection techniques and materials can provide a more comprehensive idea for the diagnosis of vitreoretinal diseases and a broader reference for the related basic research.
Objective To observe the effects of dual targets intervention on the expression of vascular endothelial growth factor (VEGF) and connective tissue growth factor (CTGF) in diabetic rat retina. Methods Forty-eight Sprague -Dawley rats were randomly divided into control group (CON1 group) and diabetes mellitus group (DM group). The rats of DM group were induced with streptozotocin injection creating a diabetic model. Retinas were obtained at eight, 10, 12 weeks after DM induction from both groups. CTGF and VEGF mRNA levels were examined by realtime reverse transcriptionpolymerase chain reaction (RT-PCR). Based on the results of above experiments, 60 rats with same conditions were selected. Fifty rats were induced with streptozotocin injection creating a diabetic model, and 10 rats comprised the control group (CON2 group). Then the 50 diabetic rats were randomly divided into ranibizumab and CTGF shRNA dual targets intervention group, ranibizumab singletarget intervention group, CTGF shRNA singletarget intervention group and nonintervention group. Retinas were obtained at one week after intervention from all the groups. CTGF and VEGF mRNA levels were examined by RT-PCR. Results The levels of CTGF mRNA were significantly higher in DM group than that in CON1 group at the 8th weeks after DM induction, and this upregulation was maintained through the 12th week (t=-2.49, -2.67, -2.42;P＜0.05). There was no difference on VEGF mRNA levels between DM group and CON1 group at the 8th weeks after DM induction(t=-0.443,P=0.669). VEGF mRNA levels of DM group started to be significantly elevated over those in the CON1 group at the 10th week, and remained to be higher at the 12th week (t=-2.35, -2.57;P＜0.05). The VEGF mRNA of ranibizumab single-target intervention group was significantly lower than that in non-intervention group (t=-3.44,P=0.014), which was similar to CON2 group (t=-1.37,P＞0.05); however, the CTGF mRNA level was significantly increased as compared to the nonintervention group (t=2.48,P＜0.05). In the CTGF shRNA single-target intervention group, the levels of CTGF and VEGF mRNA were decreased as compared to the non-intervention group (t=0.23, -2.92;P＜0.05). In the ranibizumab and CTGF shRNA dual targets intervention group, the levels of CTGF and VEGF mRNA were decreased as compared to the non-intervention group (t=-6.09, -5.11;P＜0.001), which was similar to CON2 group (t=-1.16, 1.139; P＞0.05). Conclusions Both CTGF and VEGF gene expression are up-regulated in early diabetic rat retina, and the level of CTGF increased earlier than VEGF. Ranibizumab combined with CTGF shRNA could simultaneously reduce the level of CTGF and VEGF mRNA in diabetic rat retina.