ObjectiveTo observe the clinical effect of microincision vitreoretinal surgery (VRS) assisted with intravitreal injection of ranibizumab (IVR) in severe proliferative diabetic retinopathy (PDR) treatment. MethodsThis is a prospective non-randomized controlled clinical study. A total of 60 patients (70 eyes) with severe PDR diagnosed were enrolled and divided into IVR group (31 patients, 35 eyes) and control group (29 patients, 35 eyes). IVR group patients received an intravitreal injection of 0.05 ml ranibizumab solution (10 mg/ml) first, and 3 or 4 days later they received 23G microincision VRS. Control group patients only received 23G microincision VRS. The follow-up time was 3 to 12 months with an average of (4.5±1.8) months. The logarithm of the minimal angle of resolution (logMAR) best corrected visual acuity (BCVA), intraocular pressure, the central retinal thickness (CRT) and retinal reattachment, and the incidence of postoperative complications were comparatively analyzed. ResultsThere was no topical and systemic adverse reactions associated with the drug after injection in IVR group. The incidence of post-operative vitreous hemorrhage (VH) in IVR group and control group was 8.6% and 28.6% at 1 week after surgery, 0.0% and 17.1% at 1 month after surgery, 0.0% and 8.6% at 3 month after surgery respectively. The differences were statistically significant for 1 week (χ2=4.63, P < 0.05) and 1 month (χ2=4.56, P < 0.05), but was not statistically significant for 3 months (χ2=0.24, P > 0.05). The mean post-operative logMAR BCVA of IVR group (0.81±0.40) and control group (1.05±0.42) have all improved than their pre-operative BCVA, the difference was statistically significant (t=12.78, 4.39; P < 0.05). The mean logMAR BCVA of IVR group is higher than BCVA of control group, the difference was statistically significant (t=-2.36, P < 0.05). The average post-operative CRT in IVR group was thinner than that of control group, the difference was statistically significant (t=-2.53, P < 0.05). The incidence of a transient high intraocular pressure in IVR group (14.3%) was lower than that in control group (34.3%), the difference was statistically significant (t=4.79, P < 0.05). The incidence of retinal reattachment (t=0.35), epiretinal membrane (χ2=0.97), neovascular glaucoma (χ2=0.51) was no difference between these two groups (P > 0.05). ConclusionThe minimally invasive VRS assisted by IVR treatment for severe PDR can effectively prevent postoperative VH, reduce CRT and improve visual acuity.
ObjectiveTo observe the effects on the function and structure of retina in diabetic rats by intravitreal transplantation of retinal nerve stem cells (NSC) differentiated from human umbilical cord mesenchymal stem cells (hUCMSCs). MethodsFifty clean male Sprague-Dawley rats were randomly divided into normal control with 9 rats (group A) and diabetes mellitus (DM) group with 31 rats. The DM models were induced by intraperitoneal injection of streptozocin. The rats of DM group were randomly divided into four groups after 10 weeks: rats with DM only (group B), diabetic rats with saline intravitreal injection (group C), diabetic rats with NSC intravitreal injection (group D), and 9 rats for each. The rats in the group A and B received no treatment. The retinal function was examined by the flash-electroretinogram on 2, 4, 6 weeks after intervention, the latency and amplitude of a-wave, b-wave of Rod, a-wave, b-wave of Max reactions (Max-R) and the total amplitudes of OPs were recorded. The morphological changes of retina were observed by hematoxylin-eosin staining. ResultsOn 2 and 4 weeks after the intervention, the differences of latency and amplitude of b-wave of Rod, a-wave, b-wave of Max-R and the total amplitudes of OPs among group A-D were significant (P<0.05). Compared group D with group B, C, the amplitude of b-wave of Rod, Max-R and the total amplitudes of OPs were increased (P<0.05); latency of b-wave of Max-R was decreased (P<0.05). On 6 weeks after the intervention, the amplitude of b-wave of Rod and the amplitude of a-wave, b-wave of Max-R and the total amplitudes of OPs in group D were increased compared with group B and C (P<0.05), the latency of b-wave of Rod and Max-R in group D were decreased compared with group C (P<0.05). On 10 weeks after molding, each retinal layers were disordered in diabetes mellitus group. On 2 weeks after the intervention, the number of cells in the retinal layers in group B and C were reduced compared with group A, and the structure was more disorder. On 4 weeks after the intervention, the structure of each retina layer in group D arranged less disordered, and the number of retinal ganglion cells was more than group B and C. It was also found that the retinal vascular endothelial expanded and retinal blood vessels cells proliferated. ConclusionThe function of retina in diabetes mellitus rats is improved by intravitreal injection of retinal NSCs differentiated from hUCMSCs.