Retinal function and PKC alpha expression after focal laser photocoagulation

Purpose

To examine the effects of focal laser photocoagulation on general and local retinal function and to relate electrophysiological findings with changes in protein kinase C (PKC) alpha expression.

Methods

Twelve rabbits were treated with 70 spots of laser photocoagulation in the central cone-rich retina. The operated eyes were investigated with electroretinography (full-field ERG and multifocal electroretinography, mfERG) preoperatively and at 1, 3, and 5 weeks after surgery. The expression of PKC alpha was examined at all three time points using immunohistochemistry, and PKC alpha mRNA levels were quantified using real-time polymerase chain reaction (PCR). Immunohistochemistry for glial fibrillary acidic protein (GFAP) and hematoxylin and eosin staining was employed to monitor the extent and dynamics of the morphological response.

Results

The full-field ERG revealed a significant increase in b-wave amplitudes derived from the isolated rod response (blue light) at all three time points after surgery (p?Conclusions Focal laser treatment in the rabbit eye induces local and wide-spread alterations in both rod- and cone-mediated retinal function in the form of supernormal b-wave amplitudes in the full-field ERG and increased latency in the mfERG. The electrophysiological abnormalities are accompanied by a progressive down-regulation of the PKC alpha isoenzyme in rod bipolar cells, reaching far beyond the treated area. PKC alpha is down-regulated directly by impaired protein synthesis, and also possibly indirectly by protein consumption related to GFAP up-regulation. The results indicate that focal laser photocoagulation interferes with PKC-alpha-mediated inhibitory regulation of inner retinal signal transmission.     

白内障摘除人工晶状体植入术后的糖尿病视网膜病变激光治疗

目的:观察白内障人工晶状体植入术后糖尿病视网膜病变(DR)的氩激光光凝治疗效果及光凝后的远期效果,探讨光凝治疗的时机及影响光凝的因素.方法:采用Zeiss Visulas氩离子眼科激光治疗仪对36例58眼的光凝术方法及治疗效果进行回顾性分析.结果:42眼行广泛视网膜光凝术,16眼行局部视网膜光凝术,其中6眼伴有人工晶状体后囊混浊,先期行Nd:YAG激光切开后囊膜.24眼视力提高1～2行,占42%,其中BDR 16眼,PPDR 8眼;28眼视力无变化,占48%,其中PP-DR24眼,PDR 4眼;6眼视力下降,占10%,均为PDR.3mo后行荧光素眼底血管造影(FFA)检查,新生血管大部萎缩,视网膜水肿消退.结论:适时的白内障摘除联合IOL植入,合理及时的激光治疗,是控制糖尿病患者眼底病变继续恶化的重要手段.FFA是进行正确有效激光治疗的重要参考依据,而放置大直径IOL又是完善眼底激光治疗的先决条件.     

氩激光光凝结合活血化淤中药治疗糖尿病视网膜病变

目的比较氩激光光凝结合活血化淤中药与单纯视网膜光凝治疗糖尿病视网膜病变的疗效.方法观察了68例(124眼)糖尿病视网膜病变患者.其中40例(73眼)光凝结合中药;28例(51眼)单纯光凝.观察2组治疗后的视力、眼底变化及血液流变特性.结果光凝结合中药组达到最佳视力的时间,眼底出血、水肿吸收的时间较单纯光凝组明显缩短(P＜0.05),其血液的高黏、凝、聚状态明显改善.结论氩激光光凝结合活血化淤中药治疗糖尿病视网膜病变的疗效优于单纯氩激光光凝.     

灯盏细辛联合激光光凝治疗糖尿病视网膜病变

目的:探讨灯盏细辛注射液联合视网膜激光光凝术治疗糖尿病视网膜病变的临床效果。 方法:糖尿病视网膜病变患者50例用灯盏细辛注射液联合视网膜激光光凝术治疗,对照组患者50例单纯采用羟苯磺酸胶囊口服,观察治疗前后的眼底改善和视力提高情况及血液流变学的改变。 结果:糖尿病视网膜病变患者用灯盏细辛注射液联合视网膜激光光凝术治疗后,能明显提高糖尿病视网膜病变患者的视力,明显改善患者眼部微循环,总有效率达90％,与对照组相比,差异有统计学意义（P<0.05）。 结论:灯盏细辛注射液联合视网膜激光光凝术治疗糖尿病视网膜病变,具有良好的临床疗效,能更好改善糖尿病视网膜病变的微循环状态,并延缓和改善糖尿病视网膜病变。     

Recovery of the electroretinogram in rabbits after argon laser photocoagulation

Argon laser is widely used to coagulate the diabetic retina in order to inhibit the proliferative stage of diabetic retinopathy. Ten pigmented rabbits underwent retinal photocoagulation with argon laser. Retinal function was assessed electroretinographically before treatment and at different time intervals after treatment. The ERG responses measured 4-7 days after treatment were reduced in amplitude by a degree which was proportional to the number of laser applications. In five eyes that were treated with at least 1000 applications the ERG responses were very small when measured 4 days post-treatment. However, a gradual recovery was observed and within 2 months the ERG responses approached the normal pretreatment amplitudes. Histological findings from light and electron-microscopy suggested that the ERG recovery could not be solely explained by healing of the coagulated areas. Structural differences were seen in the pigment epithelial layer between a retina obtained immediately after treatment and one studied after ERG recovery. It is suggested that changes in the electrical resistance of the pigment epithelium may contribute to the ERG reduction seen immediately after laser treatment in the rabbit and to the increase in the ERG amplitude observed during the apparent functional recovery of the retina.     

532nm激光治疗糖尿病视网膜病变的临床观察

目的:评估532nm激光治疗糖尿病视网膜病变(diabetic retinopathy,DR)的治疗效果。方法:应用532nm激光对糖尿病患者48例96眼[包括增殖前期糖尿病视网膜病变(PPDR)54眼,增殖期糖尿病视网膜病变(PDR)42眼(包括高危PDR20眼,非高危PDR22眼),合并黄斑水肿21眼]行视网膜光凝术。根据DR分期及病变严重程度行次全视网膜光凝(Sub-PRP)、标准全视网膜光凝(S-PRP)和超全视网膜光凝(E-PRP)及局限光凝和格栅样光凝,随访3mo～4a,观察视力和视网膜病变进展情况。必要时再补充激光治疗。结果:视力:提高或不变为有效,其中PPDR组有效45眼(83%),非高危PDR组有效18眼(82%),高危PDR组有效12眼(60%)。视网膜病变进展情况:视网膜水肿、渗出、出血部吸收,视网膜新生血管部分或全部消退为有效,其中PPDR组有效50眼(93%),非高危PDR组有效19眼(86%),高危PDR组有效13眼(65%)。结论:倍频532nm激光治疗DR安全有效,早期病变治疗效果好。及早发现和治疗病变,注意光凝方法和技巧,以及随访和跟踪治疗,是提高视网膜光凝疗效的关键。     

577nm激光光凝联合芪明颗粒治疗糖尿病视网膜病变Ⅲ期

目的:探讨眼底激光联合芪明颗粒治疗糖尿病视网膜病变Ⅲ期的疗效观察。方法:将2017-12/2018-06在我院眼科需要行眼底激光治疗的56例糖尿病视网膜病变Ⅲ期患者随机分为两组:试验组(芪明颗粒联合眼底激光治疗)28例,对照组(眼底激光治疗)28例。观察两组治疗后视力(BCVA),平均视野缺损(MD),黄斑中心厚度(CMT)的改变,观察时间为6mo。结果:治疗后1、3、6mo试验组、对照组患眼平均BCVA、MD值、CMT值与治疗前比较均有差异(P<0.05)。治疗后1、3mo两组患眼平均BCVA、MD值、CMT值比较均有差异(P<0.05);治疗后6mo均无差异(P>0.05)。结论:芪明颗粒短期内可减轻激光光凝对视网膜功能损害程度,促使激光损伤的快速修复,减轻糖尿病性黄斑水肿。     

Results of laser photocoagulation in patients with diabetic retinopathy developed as a complication of diabetes type 2

PURPOSE: Laser photocoagulation is a widely used method of treatment of diabetic retinopathy. The purpose of the work was to analyze the results of laser photocoagulation of the retina in patients with diabetic retinopathy, as a result of diabetes type 2. MATERIAL AND METHODS: The examined group consisted of 129 patients with diabetes type 2, treated in the Regional Centre of Diabetology and Metabolic Diseases in Lód?, who underwent laser photocoagulations as a treatment of diabetic retinopathy. Patients age were 30 to 82 years old (mean age 61), had been treated for diabetes from 1 year to 47 years (mean 17 years). Laser photocoagulations were performed in 258 eyes. The evaluation of results was based on 6 months follow-up examinations after laser treatment and comprised functional results and condition of the eye fundus. RESULTS: In the examined groups simple non proliferative diabetic retinopathy was recognized in 36 eyes (13.95%), preproliferative retinopathy in 158 eyes (61.24%) and proliferative retinopathy in 64 eyes (24.8%). Focal photocoagulations were performed in 103 eyes. Improvement in visual acuity was noted in 82 eyes (79.61%) and stabilization or improvement in the state of the eye fundus in 92 eyes (89.32%). "Grid" photocoagulation was carried out in 73 eyes, improvement in visual acuity was noted in 53 eyes (72.60%) and stabilization or improvement in the state of the eye fundus in 58 eyes (79.45%). Panretinal photocoagulation was performed in 82 eyes. Improvement or stabilization of visual acuity was observed in 46 eyes (46.10%) and stabilization of state of the eye fundus in 54 eyes (65.85%). In cases of patients with non proliferative diabetic retinopathy stabilization of visual acuity was observed in 86.11% of eyes and stabilization of the eye fundus in 94.44% of eyes. In patients with preproliferative diabetic retinopathy stabilization of visual acuity was found in 71.52% of eyes and stabilization of state of the eye fundus in 80.38% of eyes. In cases of patients with proliferative retinopathy the percentages amounted to 57.81% and 67.19%, respectively. CONCLUSIONS: The best functional results of laser photocoagulations, as well as stabilization of state of the eye fundus were achieved in patients with non proliferative retinopathy and after focal laser photocoagulations. The least favourable results were achieved in patients with proliferative diabetic retinopathy and in patients after panretinal photocoagulations. It probably results from the intensity of retinal lesions, which were an indication for these types of photocoagulations. The achieved improvement was greater regarding anatomical results, when compared to functional results. In order, to prevent the development of diabetic lesions in the eye fundus, it is necessary to carry out regular ophthalmologic check-ups, to qualify patients for laser photocoagulations, as early as possible.     

多波长氪离子激光治疗糖尿病视网膜病变疗效观察

目的观察多波长氪离子激光对116例(182眼)糖尿病视网膜病变(DR)的疗效。方法根据患者病变性质、部位、分期和屈光间质情况分组,选择不同波长激光进行不同方法视网膜光凝。局部光凝组124眼,全视网膜光凝组58眼,术前均行视力、检眼镜、裂隙灯显微镜加三面镜和荧光素眼底血管造影检查,术后随访1～1.5年。结果局部光凝组病变较轻40眼,病变较重84眼,治疗1次后随访显示二者疗效有显著性差异(P<0.05)。全视网膜光凝组,其中增生前期DR26眼,光凝后有效22眼(85%)、无效4眼(15%)。增生期DR32眼,光凝后有效20眼(63%)、无效12眼(37%)。结论多波长氪离子激光是治疗DR的有效方法,依据病变情况使用不同波长扩大了治疗DR的适应证。早期进行局部光凝治疗DR可减少治疗次数和并发症。     

氩离子激光光凝前后糖尿病大鼠眼内组织中色素上皮衍生因子的表达

目的:观察氩离子激光视网膜光凝后糖尿病大鼠眼玻璃体及视网膜组织内色素上皮衍生因子(pigment epithelium-derived factor,PEDF)蛋白质表达的变化。方法:选用先天性糖尿病GK大鼠20只,对所有大鼠左眼施行氩离子激光视网膜光凝,右眼不进行光凝,作为自体对照。激光光凝后3d处死动物,取出眼球,WesternBlot和免疫组织化学染色检测玻璃体和视网膜组织中PEDF蛋白质表达的变化。结果:氩离子激光视网膜光凝后糖尿病大鼠玻璃体和视网膜中PEDF蛋白的表达均明显升高(P<0.01);且PEDF蛋白主要存在于RPE细胞层、光感受器细胞层、外核层和神经节细胞层,内核层表达的强度低于上述4层。结论:氩离子激光光凝可以上调糖尿病大鼠玻璃体和视网膜组织PEDF表达,抑制新生血管形成,达到治疗的目的。     

白内障术后糖尿病视网膜病变的光凝治疗

观察白内障术后糖尿病视网膜病变的光凝治疗效果及光凝后的远期复明效果 ,探讨光凝治疗的时机 ,影响光凝的因素。方法 :对我院 5年来行白内障手术的伴有糖尿病视网膜病变且具有光凝指征的病人 ,将其分为两组 ,白内障术后行光凝治疗组5 3例 ,未行光凝治疗组 45例。结果 :白内障术后早期光凝治疗的病人 ,糖尿病视网膜病变稳定 ,黄斑水肿消褪或减轻 ,视力保持稳定。未行光凝治疗的病人 ,视网膜病变加重 ,视力下降甚至失明。结论 :伴有糖尿病视网膜病变的白内障病人行白内障手术后 ,如有光凝指征 ,应尽早行光凝治疗。这对于控制或延缓糖尿病视网膜病变的进展 ,稳定病人视力 ,提高这些白内障病人的远期复明效果 ,有重要意义。     

玻璃体手术中超全视网膜光凝对增生性糖尿病视网膜病变疗效影响

目的：探讨玻璃体手术中超全视网膜光凝对增生性糖尿病视网膜病变(proliferative diabetic retinopathy, PDR)疗效的影响。

方法： 回顾性分析2011-03/2013-03因玻璃体积血或玻璃体视网膜牵拉改变在我院接受玻璃体手术的糖尿病视网膜病变患者70例70眼,根据患者视网膜光凝范围不同将其分为超全视网膜光凝组40眼和全视网膜光凝组30眼,分别观察两组患者的最佳矫正视力、眼压及视网膜血管变化等情况,并对结果进行统计学分析。

结果：两组患者术前眼部状况、术后3mo最佳矫正视力及眼压,差异均无统计学意义(均P>0.05)。两组患者视网膜血管渗漏、后极部硬性渗出和后极部出血点的发生率比较,差异有统计学意义(均P<0.05)。两组患者视网膜无灌注区、视盘血管渗漏的发生率比较,超全视网膜光凝组均优于全视网膜光凝组,差异有统计学意义(P=0.04、0.02)。术后两组患者黄斑水肿发生情况比较,差异无统计学意义(P=1.00),黄斑水肿消失时间比较,超全视网膜光凝组优于全视网膜光凝组,差异有统计学意义(P<0.05)。

结论：治疗PDR患者时,在玻璃体手术中采用超全视网膜光凝在视网膜无灌注区、视网膜血管渗漏、视盘血管渗漏等方面的疗效好于全视网膜光凝,但过量的视网膜光凝对视网膜及脉络膜有明显的损伤,因此治疗过程中在尽可能覆盖视网膜病变区的同时,掌握好激光能量及光斑数量对预防并发症的发生同样重要。     

Combined modified grid and panretinal photocoagulation for diffuse diabetic macular edema and proliferative diabetic retinopathy

PURPOSE: To determine the effectiveness of combined macular modified grid and peripheral panretinal photocoagulation in diabetic eyes with both macular edema and proliferative retinopathy. MATERIAL AND METHODS: We evaluated 52 eyes with diffuse diabetic macular edema and proliferative diabetic retinopathy. Treatment was performed in two sessions consisting of initial modified grid to the macula and panretinal photocoagulation to the inferior half of the peripheral retina, followed 2 to 4 weeks later by panretinal photocoagulation to the superior half. RESULTS: At one year, visual acuity was improved in 8%, stable in 79%, and worse in 13%. At two years, visual acuity was improved in 4%, stable in 72%, and worse in 24%. Macular edema resolved in 43 of 46 eyes (93%), and proliferative retinopathy was reduced in 25 of 29 eyes (86%) at last examination. CONCLUSION: Combined macular modified grid and peripheral panretinal photocoagulation is an effective treatment approach in diabetic eyes with both macular edema and proliferative retinopathy. Laser photocoagulation in those diabetic eyes with diffuse diabetic macular edema and proliferative diabetic retinopathy can be completed in less number of treatment sessions with this method, compared to conventional treatment techniques.     

Retinopathy risk factor regression after laser panretinal photocoagulation for proliferative diabetic retinopathy

Fifty eyes of patients with proliferative diabetic retinopathy were followed at frequent intervals to determine the rapidity and stability of retinopathy risk factor regression after argon laser panretinal photocoagulation. Retinopathy risk factors regress rapidly after laser photocoagulation. The incidence of eyes at high risk for severe visual loss (eyes with 3 or more retinopathy risk factors) decreased from 100% prior to treatment to 28% three weeks after treatment. The early response to treatment was a good prognostic indicator of longer term results. Seventy-two percent of eyes which improved from a high- to a low-risk category by three weeks continued to remain at low risk at six months. Sixty-four percent of eyes which failed to improve to a low-risk category by three weeks continued to remain at high risk at six months. The early response to laser panretinal ablation may be used to predict longer-term results.     

Macular oedema and retinal neovascularisation in juvenile diabetics

Thirteen young diabetic patients with peripheral capillary non perfusion who presented with symptoms of mild maculopathy were reviewed retrospectively. In this group, peripheral retinal ischaemia was often overlooked and a rapidly progressive proliferative retinopathy developed. Fluorescein angiography of the peripheral retina showed capillary closure, but with preservation of arterioles and venules.In this series, half of the eyes lost vision. In seven eyes where the peripheral ischaemia was treated by pan retinal photocoagulation, the maculopathy resolved without any specific laser treatment to the macula.In young diabetics presenting with maculopathy, the peripheral retina should be examined for ischaemia, and if present, pan retinal laser photocoagulation should be performed. Focal treatment for the macular disease can be delayed until after the peripheral photocoagulation, as the maculopathy may remit.     

眼底激光联合玻璃体腔注药治疗合并黄斑水肿的糖尿病性视网膜病变的临床观察

目的:探讨全视网膜光凝术联合玻璃体腔注药术治疗合并黄斑水肿的糖尿病性视网膜病变的效果。方法:应用532半导体绿激光治疗机对视网膜病变达Ⅲ期以上同时合并黄斑水肿的糖尿病性视网膜病变患者,行全视网膜光凝术,术后1wk行曲安奈德玻璃体腔注射。结果:治疗后241眼中视力提高及无下降者218眼,有效率占90.5%,视力下降及玻璃体出血23眼,占9.5%,治疗前后有非常显著的临床意义。结论:全视网膜光凝术联合玻璃体腔注药术治疗合并黄斑水肿的糖尿病性视网膜病变安全有效。     

行全视网膜光凝时不同象限顺序对治疗效果影响的临床研究

目的:利用光学相干断层扫描仪(OCT)视网膜地形图,探讨糖尿病性视网膜病变患者行不同顺序全视网膜光凝术前后对黄斑水肿的影响。方法:随机选择发生糖尿病性视网膜病变Ⅲ和Ⅳ期患者共19例(30眼),按不同象限顺序行全视网膜光凝。分成3组,每组10眼。第1组光凝顺序鼻侧、下方、上方、颞侧象限;第2组下方、鼻侧、上方、颞侧象限;第3组颞侧、下方、鼻侧、上方象限。每周一个象限,共4周完成。分别在术前、术后1,2,3,4,8wk测量视网膜地形图,比较各组间黄斑水肿程度及视力有无差异。结果:第1组和第2组术后8wk视力较术前轻度提高,第3组术后8wk视力较术前轻度下降,差异无统计学意义(P>0.05);第1组和第2组术后4wk黄斑视网膜厚度较术前增加,差异有统计学意义(P<0.05);第3组术后4wk黄斑视网膜厚度较术前增加,差异有统计学意义(P<0.01);术后8wk3组黄斑视网膜厚度均较术前变薄,前两组比第3组减轻幅度大,第1组、第2组在中心环处视网膜水肿减轻同术前比差异有统计学意义(P<0.05),第3组中心环处视网膜厚度同术前相比差异无统计学意义(P>0.05),余各处3组较术前相比差异均无统计学意义(P>0.05)。结论:对于Ⅲ期和Ⅳ期糖尿病性视网膜病变全视网膜光凝时,第2组获得较好视力,引起黄斑水肿较轻;通过OCT检查视网膜地形图是观察糖尿病性视网膜病变激光手术前后黄斑水肿的一种有效、敏感方法。     

高原地区糖尿病性视网膜病变激光光凝治疗的疗效观察

目的:观察氩激光视网膜光凝(panretinal photocoagulation,PRP)治疗高原地区糖尿病视网膜病变(diabetic retinopathy,DR)的临床疗效。方法:根据眼底荧光血管造影(fundus fluorescence angio-graphy,FFA)的结果,对176例257眼分别为增殖前期糖尿病性视网膜病变(preproliferative diabetic retinopathy,PPDR)62眼、增殖期糖尿病性视网膜病变(proliferative diabetic retinopathy,PDR)195眼进行氩激光视网膜光凝治疗。治疗前、完成最后一次光凝后3mo分别对患者的视力、眼底、FFA进行检查并追踪观察6mo～2a。结果:本组257眼经视网膜光凝治疗后215眼有效,总有效率为83.7%。其中PPDR62眼,有效57眼(91.9%);PDR195眼,有效158眼(81.0%),经统计学检验,两者有显著差异(P<0.01)。光凝治疗后视力提高有59眼(23.0%);155眼视力稳定不变(60.3%);视力下降43眼(16.7%)。本组病例治疗后有28眼(10.9%)出现黄斑水肿加重,视力下降,经2～3wk后均恢复至光凝治疗前水平。结论:氩激光视网膜光凝术治疗DR是安全、有效的方法,尽早行氩激光视网膜光凝治疗,对于控制或延缓DR的进展,稳定患者视力有重要意义,并可以有效防止DR致盲。     

Development of glutamate receptor subunit 2 immunoreactivity in postnatal rat retina

Previous studies have shown that the expression of glutamate receptor subunits is developmentally regulated and have been implicated in processes of cell differentiation during postnatal life. The tissue localization and developmental pattern of the glutamate receptor 2 subunit of the alpha-amino-3-hydroxy-5-methyl-4-isoxazoleproprionate (AMPA) receptor were investigated by means of immunohistochemistry and immunoblotting. Labeling of amacrine and ganglion cells and the inner plexiform layer appeared early during development, while glutamate receptor 2 subunit expression in the outer plexiform layer started after the first postnatal week. The distribution of labeling within the inner plexiform layer changed from nonorganized to laminated appearance prior to eye-opening. There was an increasing number of positive amacrine and ganglion cell somata during the first 2 weeks, but their number decreased considerably as the retina matured and were seen at least up to 35 days of postnatal development. Little labeling was found in the ganglion cell layer and in the inner plexiform layer of late postnatal and adult retina. Labeling in the outer plexiform layer and of bipolar cell somata appeared to increase in the developing retina. Glur2 labeling of these cells and the outer plexiform layer became discernible during the second postnatal week, and this labeling was present in the adult as well. Immunoblotting showed that GluR2 protein levels were similar at postnatal days 7 and 10, but slightly decreased between the second and fourth postnatal weeks. Our data imply that the immunological expression of glutamate receptor 2 subunit in the inner plexiform layer decreases as a function of age, and is correlated with developmental event(s) in the postnatal retina.     

Photocoagulation given additional benefit by calciumdobesilate (author's transl)]

52 patients with diabetic retinopathy stade III or IV (after Thiel) received on both eyes a photocoagulation treatment. 26 patients received subsequently Calciumdobesilate for 5 to 68 months. It could be shown, that the effect of photocoagulation treatment on alterations of the retina in diabetic patients was clearly enhanced by Calciumdobesilate.