Diabetic retinopathy (DR) is one of the microvascular complications of diabetes mellitus (DM). Like other macrovascular complications of DM, the development and progression of DR is influenced by a variety of systemic and local factors. It is essential to understand the importance of multidisciplinary collaboration. Systemic risk fators such as hyperglycemia, hypertension, dyslipidemia and diabetic nephropathy should be treated before effective DR management can be implemented. Through multidisciplinary collaboration, we can prevent the development of DR, slow the progression of DR, and improve the safety of perioperative care. Thereby enhancing the level of prevention and control of DM complications, including DR.
Diabetic retinopathy is a serious complication of diabetes and is the leading cause of blindness in people with diabetes. At present, there are many views on the pathogenesis of diabetic retinopathy, including the changes of retinal microenvironment caused by high glucose, the formation of advanced glycation end products, oxidative stress injury, inflammatory reaction and angiogenesis factor. These mechanisms produce a common pathway that leads to retinal degeneration and microvascular injury in the retina. In recent years, cell regeneration therapy plays an increasingly important role in the process of repairing diseases. Different types of stem cells have neurological and vascular protection for the retina, but the focus of the target is different. It has been reported that stem cells can regulate the retinal microenvironment and protect the retinal nerve cells by paracrine production, and can also reduce immune damage through potential immunoregulation, and can also differentiate into damaged cells by regenerative function. Combined with the above characteristics, stem cells show the potential for the repair of diabetic retinopathy, this stem cell-based regenerative therapy for clinical application provides a pre-based evident. However, in the process of stem cell transplantation, homogeneity of stem cells, cell delivery, effective homing and transplantation to damaged tissue is still a problem of cell therapy.
Objective To observe the functional and morphological changes of macular after panretinal photocoagulation（PRP）in the patients with diabetic retinopathy（DR）.Methods A total of 57 eyes of 34 patients with DR undergoing PRP were enrolled in this prospective and self-reflection study. Comparatively analyze the changes of the best visual acuity（BCVA）, optical coherence tomography (OCT) and multi-focal electroretinography (mfERG) before PRP,20 days, 3 months and more than 9 months after PRP. Statistical analyses were performed by wilcoxon, chisquare, Dunnett-t, LSD-t tests and spearman related analyses. The changes of macular function and foveal retinal thickness before and after PRP were comparatively analyzed.Results BCVA of all patients reduced at 9 months after PRP（P=0.022）.The amplitude density of mfERG P1 of ring 2 decreased at 20 days after PRP（P=0.039）,then recovered at 3 months and decreased again at 9 months（P=0.014）.The amplitude density of mfERG P1 of ring 3-5 decreased at 20 days,3 months and more than 9 months after PRP（20 days: ring 3: P=0.000,ring 4: P=0.001, ring 5: P=0.000；3 months: ring 3:P=0.000, ring 4: P=0.006, ring 5: P=0.001; more than 9 months: ring 3: P=0.000,ring 4: P=0.000, ring 5: P=0.000）. The amplitude density of mfERG P1 of ring 1 was significantly lower at 9 months after PRP（P=0.050）. The foveal retinal thickness increased at 20 days after PRP(P=0.007), then recovered at 3 months or later. Cystoid macular degeneration was found in 6 eyes(10.5%) at 20 days after PRP.Conclusions After the treatment of PRP, there were some extend reduction of the macular function, a transient increase on foveal retinal thickness. Combined mfERG and OCT can be a comprehensively and objectively assessment of macular function and morphology.
Objective To compare the therapeutic effects of 577 nm laser and 532 nm laser panretinal photocoagulation (PRP) in the treatment of non-proliferative diabetic retinopathy (NPDR). Methods This is a prospective controlled study. A total of 23 patients (41 eyes) with clinically diagnosed severe NPDR were randomly divided into two groups including 577 nm group (11 patients, 20 eyes) and the 532 nm group (12 patients, 21 eyes). 577 nm group and 532 nm group received 3 - 4 times PRP with single-point mode. The laser energy and the number of laser spots were compared, and the laser energy density was calculated. Before treatment and 1 day, 1, 3, 6 and 12 months after treatment, the changes of best corrected visual acuity (BCVA), average threshold sensitivity, a/b-wave amplitude of flash ERG (F-ERG) in the 30° - 60° visual field, and fundus fluorescein angiography (FFA) were compared between two groups. Results The response rate was 85.0% and 23.8%, respectively in the 577 nm and 532 nm group, the difference was statistically significant (χ2=15.43，P < 0.05).Compare to the pre-treatment measurement, the average threshold sensitivity, a/b wave amplitude of F-ERG and the 30° - 60°visual field were reduced at 1 day after treatment both in the 577 nm and 532 nm group, the difference were statistically significant (F=8.68, 7.57, 4.52; P < 0.05). The average threshold sensitivity (t=2.41, 3.48, 1.23), a/b wave amplitude (a wave: t=5.82, 4.45, 7.83；b wave: t=5.40, 3.23, 4.67) of F-ERG were different between 577 nm and 532 nm group at 3 , 6 and 12 months after treatment (P < 0.05). There was no retinal neovascularization and non-perfusion region in two groups at 6 months after treatment. The average laser power were (436.25±54.65) and (446.43±35.61) mW, number of laser spots were (1952.95±299.09) and (2119.05±302.69) spots, energy density were (7.60±1.30) and (7.60±3.00) mW×ms/μm2 in the 577 nm group and 532 nm group, respectively. There was no difference in average laser power (t=1.35), number of laser spots (t=2.85) and energy density (t=1.99) between two groups (P > 0.05). Conclusion Compared with the 532 nm laser, 577 nm laser treatment has better visual outcomes for NPDR patients.
Objective To observe the influence of rAAV-mediated antisense vascular endothelial growth factor (rAAV-aVEGF165) on the expression of retinal VEGF in diabetic rats. Methods 40 Sprague-Dawley rats induced diabetic rat model by intraperitoneal injection with streptozotocin (STZ). 32 rats were involved in study besides death and blood sugar recovery in experimental process, 16 spragud-Dawleg (SD) rats were received intravitreal injection with rAAV-aVEGF165 (1010 pfu) as experimental group, another group of Sprague-Dawleg (SD) rats were injected with phosphate buffered saline (PBS) as control group. One and five month after model establishment, the expression of retinal VEGF was evaluate by immunhistochemistry and Western blot; the retinal vasular was examined by transmission electron microscopy. Results On 1 month,the expression of retinal VEGF was lowest in each group. On 5 month, the expression of retinal VEGF was decreased in experimental group which compared to control, the difference are statistically significant （t=23.87,Plt;0.01）. The transmission electron microscopy results showed that retina has no obvious chages in experimental group, however,contral group showed fragmental thickening and splitting of basement membrane, swelling and deformation of endothelia cells,fingerlike prcess into the capillary cavity,and uneven distibution of heterochromatin in pericytes. Conclusion rAAV-aVEGF165 can reduce the expression of retinal VEGF thereby preventing occurrence and development of diabetic retinopathy. rAAV is an effective vectors of eye antisense gene. （Chin J Ocul Fundus Dis，2008，24：255-258）
Objective Methods Ninety male Wister rats were randomly divided into normal control group, diabetic group and FTY720 group, thirty rats in each group. Diabetes was induced by giving a single intraperitoneal injection of streptozocin. FTY720 group was administered with FTY720 at a dose of 0.3 mg/kg by oral gavage daily for 3 months after establishment of diabetes. All rats were used for experiments following intervention for 3 months in FTY720 group. Immunohistochemical staining was used to observe the expression and distribution of intercellular adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1), and the positive cells were counted. Real-time reverse transcription PCR was used to measure mRNA expression of ICAM-1 and VCAM-1. Fluorescein isothiocyanate-Concanavalin A perfusion was used to detect retinal leukocytes adhesion. Evans blue (EB) perfusion was used to analyze retinal vascular permeability. Immunofluorescence staining was used to detect retinal inflammatory cells infiltration. Results In diabetic group, both ICAM-1(t=12.81) and VCAM-1 (t=11.75) positive cells as well as their mRNA expression (t=16.14, 9.59) were increased compared with normal control group, with statistical significance (P < 0.05). In FTY720 group, both ICAM-1(t=-9.93) and VCAM-1 (t=-6.61) positive cells as well as their mRNA expression (t=-15.28, -6.10) were decreased compared with diabetic group, with statistical significance (P < 0.05). Retinal leukocytes adhesion (t=16.32) and EB permeability (t=17.83) were increased in diabetic group compared with normal control group, while they were decreased in FTY720 group compared with diabetic group(t=-9.93, -11.82),with statistical significance (P < 0.05). There were many CD45 positive leukocytes infiltration in retina of diabetic group, including CD11b positive macrophage/activated microglia, while both of them were little in FTY720 group. Conclusions FTY720 can decrease retinal leukocytes adhesion, reduce retinal vascular permeability and inflammatory cells infiltration, which is associated with down-regulation of ICAM-1 and VCAM-1.
ObjectivesTo evaluate the effect of peeling of internal limiting membrane (ILM) on the postoperative visual acuity in patients with diabetic macular edema, and to detect the role indocyanine green (ICG) plays in the surgery of peeling of ILM. MethodsThirty patients (31 eyes) with diabetic retinopathy at proliferative stage with macular edema underwent vitrectomy. The patients were randomly divided into two groups: 16 eyes in group A underwent single vitrectomy with panretinal photocoagulation and ocular filling with 20% SF6; 15 eyes in group B underwent vitrectomy and peeling of ILM after the posterior pole was stained with ICG. All of the patients were asked to keep the posture of facing down for 10-14 days. The follow-up lasted 3-12 months.ResultsIn 16 eyes in group A, the visual acuity increase of 2 or more lines in 10 (62.5%) and alleviation of macular edema in 9 (56.2%) were found; the postoperative average macular retinal thickness examined by optic coherence tomography (OCT) was 393 μm. In 15 eyes in group B, the visual acuity increase of 2 or more lines in 14 (93.3%) and alleviation of macular edema in 14 (93.3%) were found; the postoperative average macular retinal thickness was 319 μm. The postoperative improvement of visual acuity in group B was much better than that in group A (X2=4.210, P=0.05), while the postoperative macular retinal thickness in group B was obviously lower than that in group A (P＜0.01). The operative sample was proved to be the ILM. ConclusionsVitrectomy is effective for diabetic macular edema and the curative effect may be improved by peeling of ILM; ICG can dye ILM well, which ensures the safe and accurate peeling of ILM.(Chin J Ocul Fundus Dis, 2005,21:138-141)