Objective To explore the correlation between retinal extracellular edema and vitreous contraction in rabbits. Methods Seventeen pigmented rabbit models with retinal vein occlusion (RVO)was set up by laser photocoagulation. Retinal vascularity area was pathologically examined 1 month later.The vitreous gellength under the gravity condition and the percentage of its weight in the rabbits with extraeellular edema was observed. The mechanisms were investigated by Western immunoblotting of type II collagen.Results Extracellular edema was found in 13 experimental eyes 1 month after the formation of RVO (76.5~) with contracted vitreous gel and released watery liquid, and the a component of type II collagen was cross-linked together to form high-molecular-weight components of 1] and 7, which weakened the stability of collagen net structure.Conclusions Vitreous contraction and retinal extracellular edemawere correlated. The main reason may be the cross-links of vitreous collagen that damages the stability of collagen structure. (Chin J Ocul Fundus Dis，2004，20：2-32)
Diabetic macular edema (DME) is the most common retinopathy that seriously threatens the visual function of diabetic patients, and it represents a major cause of blindness especially among people in working age. Ocular VEGF inhibitors are most often used as a first line therapy for DME, and have revolutionary significance in improving visual outcomes. However, there remain 30%-50% patients who fail to respond to anti-VEGF treatment, and the need for frequent injections brings a substantial treatment burden to patients and society. Novel therapeutic strategies include improving efficacy and duration of anti-VEGF drugs, targeting inflammation, the plasma kallikrein–kinin system, the angiopoietin-Tie2 system, neurodegeneration and other alternative pathways, as well as using subthreshold and targeted laser therapy. It is still challenging in the individualized management of DME to identify non-responders to anti-VEGF drugs and to establish a standardized regimen for the switch from anti-VEGF therapy to anti-inflammatory or other alternative treatment. Further research and development of new therapies, as well as preventive and screening strategies, are needed to reduce the impact of diabetic retinopathy and DME on public health.
Retinal vein occlusion (RVO) is one of the most common retinal vascular diseases causing blindness, macular edema (ME) is often secondary to it, which causes serious visual impairment to patients. Imaging biomarkers in the changes of retina and choroid of ME secondary to RVO (RVO-ME) have important clinical value in the evaluation of condition, curative effect and visual acuity prediction of patients with RVO-ME. Among them, the disorganization of the retinal inner layers, the integrity of external limiting membrane and ellipsoid zone, and the change of central macular thickness are reliable indexes to evaluate the prognosis of visual acuity; hyperreflective foci, subretinal fluid and intraretinal fluid can be used as important parameters to reflect the level of inflammation; prominent middle limiting membrane and paracentral acute middle maculopathy are the objective basis for judging the degree of retinal ischemia; the changes of choroidal vascular index and choroidal thickness also have potential advantages in evaluating the progress of the disease. Accurately grasp the characteristics of biological markers of RVO-ME related optical coherence tomography is conducive to its reasonable and accurate use in the clinical diagnosis and treatment of RVO-ME, and helpful to further explore the pathogenesis of the disease.
Objective To observe the therapeutic effect of radial optic neurotomy (RON) for ischemic central retinal vein occlusion (CRVO) with macular edema. Methods The clinical data of 6 patients with ischemic CRVO combined with macular edema who had been treated with vitrectomy and radial optic neurotomy were retrospectively analyzed. The pre- and post-operative visual acuity, results of fundus fluorescein angiography (FFA) and optic coherence tomography (OCT), including the macular thickness, fluorescein filling in retinal veins, retinal hemorrhages and papilloedema were analyzed and compared. Results In the 6 patients, the visual acuity increased in different degrees and retinal hemorrhages decreased evidently. Macular edema was alleviative in 5 patients, retinal vein dilatation meliorated in 4, and papilloedema disappeared in 2. Conclusion RON may alleviate macular edema in patients with ischemic CRVO, but the relation of the therapeutic effect and vitrectomy can not be eliminated. (Chin J Ocul Fundus Dis, 2005,21:3-5)
ObjectiveTo evaluate the effect of intravitreous injection with triamcinolone acetonide (TA) on macular edema.MothodHaving been examined by ophthalmoscopy, optic coherent tomography (OCT), retinal thickness analyzer (RTA), and fundus fluorescein angiography (FFA), 33 patients (37 eyes) with diffused and (or) cystoid macular edema caused by diabetes and retinal venous occlusion were intravitreously injected with 0.1 ml triamcinolone acetonide (40 mg/ml). During 1-9 month followup period, the visual acuity, intraocular pressure, inflammatory extent, manifestation of lens and fundus were observed, the retinal thickness was examined by OCT and RTA, and vascular leakage were detected by FFA.ResultsMacular thickness was (244.07±118.80), (195.53±57.70), and (181.42±54.79) μm respectively 1, 2, 3 months after treatment; while macular thickness was (724.35±227.41) μm before the treatment. The difference was statistically significant （t =10.72, 12.84, 13.90; P lt;0.001）. The visual acuity was 0.39±0.19, 0.45±0.24, and 0.43±0.21 respectively, comparing with the visual acuity before the treatment (0.20±0.16), the difference was statistically significant （t =4.445, 4.349, 3.474; P lt;0.001, lt;0.001, 0.03）；The result of FFA showed less leakage of fluorescein and proliferative lesion. Four pateints had the ocular pressure ≥25 mm Hg (1 mm Hg=0.133 kPa) in 9 who had ≥20 mm Hg. Recurrence of macular edema was found in 4 eyes of 3 patients 4 and 6 months after the treatment, respectively. No infection or aggravation of lenticular turbidness occurred.ConclusionIntravitreous injection with TA can be used to treat macular edema due to diabetes and retinal venous occlusion, and recurrence of macular edema or increase of intraocular pressure may occur in some patients.(Chin J Ocul Fundus Dis, 2005,21:205-208)
ObjectiveTo investigate the correlation of visual sensitivity, best corrected visual acuity (BCVA) and central retinal thickness (CRT) in diabetic macular edema (DME).MethodsA retrospectives study. Forty-five eyes of 30 patients in DME were included. There were 20 eyes of 16 males, 25 eyes of 14 females, with an average age of 54.49±7.45 years. All the patients had type 2 diabetes; the average duration of diabetes was over 10 years. The BCVA examination was performed using the international standard visual acuity chart, which was converted into logarithmic logarithm (logMAR) visual acuity. The following parameters provided by the MAIA microperimetric device were evaluated, including average threshold (AT), macular integrity index (MI), fixation indexes (P1 and P2), bivariate contour ellipse area (BCEA) for 63% and 95% of points, and horizontal and vertical axes of the ellipse of fixation (H63, H95, V63, V95). The CRT was measured and the integrity of the ellipsoidal band was observed by optical coherence tomography (OCT). The integrity of the ellipsoid band was divided into continuous smooth (group A): fully visible; part of the light band was interrupted (B group): not completely visible; missing light band (C group): completely invisible. Pearson correlation analysis was used to analyze the correlation between the factors; non-parametric tests were used to compare the logMAR BCVA, AT, and CRT between the different ellipsoid zone integrity groups; multiple linear regression analysis was used to analyze factors related to AT.ResultsPearson correlation analysis showed that the logMAR BCVA was positively correlated with MI (r=0.303, P=0.04) and CRT (r=0.342, P=0.02), negatively correlated with AT (r=?0.59, P=0.00) and P1 (r=?0.38, P=0.01). There was negative correlation between AT and MI (r=?0.55, P=0.00). The result of multivariate linear regression analysis showed that the logMAR BCVA is inversely correlated with AT (t=?3.53, P=0.001). Group A, B and C were 23, 17 and 5 eyes in the 45 eyes, respectively. There were significant differences in logMAR BCVA, AT, and CRT between the three groups of eyes (P=0.045, 0.049, 0.018).ConclusionsIn DME patients, the logMAR BCVA was positively correlated with CRT, negatively correlated with AT and P1. The logMAR BCVA is inversely correlated with AT. Microperimetry combined with OCT and visual acuity can be used to assess the visual function of patients with DME.
The prevalence of diabetes mellitus in adults of China has reached 12.8%. Diabetic retinopathy (DR) accounts for approximately 1/4-1/3 of the diabetic population. Several millions of people are estimated suffering the advanced stage of DR, including severe non-proliferative DR (NPDR), proliferative DR (PDR) and diabetic macular edema (DME), which seriously threat to the patients’ vision. On the basis of systematic prevention and control of diabetes and its complications, prevention of the moderate and high-risk NPDR from progressing to the advanced stage is the final efforts to avoid diabetic blindness. The implementation of the DR severity scale is helpful to assess the severity, risk factors for its progression, treatment efficacy and prognosis. In the eyes with vision-threatening DR, early application of biotherapy of anti-vascular endothelial growth factor can improve DR with regression of retinal neovascularization, but whether it is possible to induce capillary re-canalization in the non-perfusion area needs more investigation. Laser photocoagulation remains the mainstay treatment for non-center-involved DME and PDR.
Objective To observe the short-term effect of changing the sequence of PRP and MLP on the pre-proliferative or proliferative diabetic retinopathy patients with clinical significant macular edema (CSEM). Methods Sixty-three consecutive pre-proliferative or proliferative diabetic retinopathy outpatients (103 eyes) with clinical significant macular edema were selected and divided into two groups: 54 eyes in patients of group A accepted MLP one month prior to PRP and 49 eyes in patients of group B accepted the photocoagulative therapies in a contrary sequence. All the patients were followed up for 3 to 13 months and visual acuity. Light sensitivity of 5deg;macular threshold, and FFA were performed pre- and post-photocoagution. Results The improvement of visual acuity was found to be better in group A than that of group B (Plt;0.01) 2 months after the therapy, since then, there was no significant defference (Pgt;0.05) in both groups. Three and 4 months after the treatment, there was no significant difference in change of light sensitivity of 5deg;macular threshold in both groups. The macular leakages of 59 eyes, 32 ingroup A and 27 in group B, were well controlled. Conclusion Among the pre-proliferative or proliferative diabetic retinopathy patients with CSEM, visual acuity of those who accept MLP prior to PRP more rapidly than those who accept contrary sequence of photocoagulation, but the changing of therapeutic sequence might have no dramatic influence on light sensilivity of 5deg;macular threshold. (Chin J Ocul Fundus Dis,2000,16:150-152)
Objective To expolre the factors which affect the size of diabetic,macular fobeal avascss scular zone(FAZ). Methods Making ten years of duration of diabetes a limit,79 nonproliferative and early proliferative diabetic patients were divided into 2 groups.Diabetic retinopathy severity level was diveided into 4 stages,and the macular edema was subdivided into focal、diffuse and cystoid according to fluorescein leakage of foveomacular region.All patients were measured FAZ with Heidelberg scanning laser fluoresceion angiography system and then compaired the size of FAZ of patients with different duration of diabetes、diabetic retinopathy severity level and macular edema status.The results were performed analysis of variance and t test. ResultsThe study shown the size of FAZ was not directly related to the duration of diabetes(t=1.3854,Pgt;0.1);There were significant differences about the size of FAZ of patients with different diabetic retinopathy severity level(F=7.6251,P＜0.01)and macular edema status(F=5.4369,P＜0.01)． Conclusion The size of FAZ was significantly increased in diabetic patients.It was enlarged with the development of diabetic retinopathy severity level,but it was not related to duration of diabetes. (Chin J Ocul Fundus Dis,2000,16:155-156)
Objective To evaluate the therapeutic effect of laser-induced chorioretinal venous anastomosis on macular edema of non-ischemic retinal vein occlusion. Methods Thirty-seven eyes of 37 cases of non-ischemic retinal vein occlusion received the treatment of laserinduced chorioretinal venous anastomosis and were followed up for 6～12 months. All affected eyes underwent the clinical examinations of visual acuity, ocular fundus photography, fundus fluoreceine angoigraphy (FFA) and light sensitivity of central 5 degree of the retina, and the pre- and post-operative clinical materials were analyzed. Results Successful chorioretinal venous anastomosis was formed in 18 eyes (48.6%) within 2 months after laser photocoaglation, with the mean best improved corrected visual acuity of (4.25±0.46) lines, while the mean best corrected visual acuity of the other 19 eyes with unsuccessful anastomosis decreased (0.20±0.54) lines（P＜0.001）. The light sensitivity of central 5 degree of the 18 eyes with successful anastomosis improved（P＜0.001）, with resolution of macular edema in 16 eyes, although cystoid macular edema in 2 eyes remained no change. The light sensitivity of central 5 degree of the 19 eyes with unsuccessful anastomosis have decreased（P＜0.05）, with aggrevation of the macular edema. Conclusion Successful laser-induced chorioretinal anastomosis can resolute the macular edema caused by retinal vein occlusion, especially for diffused macular edema caused by early retinal vein occlusion. (Chin J Ocul Fundus Dis,2002,18:10-12)