The Effect of Pattern Scan Laser Photocoagulation on Peripapillary Retinal Nerve Fiber Layer Thickness and Optic Nerve Morphology in Diabetic Retinopathy

Purpose

To evaluate the effect of pattern scan laser (PASCAL) photocoagulation on peripapillary retinal nerve fiber layer (RNFL) thickness, central macular thickness (CMT), and optic nerve morphology in patients with diabetic retinopathy.

Methods

Subjects included 35 eyes for the PASCAL group and 49 eyes for a control group. Peripapillary RNFL thickness, cup-disc area ratio and CMT were measured before PASCAL photocoagulation and at 2 and 6 months after PASCAL photocoagulation in the PASCAL or control groups.

Results

The average RNFL thickness had increased by 0.84 µm two months after and decreased by 0.4 µm six months after PASCAL photocoagulation compared to baseline, but these changes were not significant (p = 0.83, 0.39). The cup-disc area ratio was unchanged after PASCAL photocoagulation. CMT increased by 18.11 µm (p = 0.048) at two months compared to baseline thickness, and partially recovered to 11.82 µm (p = 0.11) at six months in the PASCAL group.

Conclusions

PASCAL photocoagulation may not cause significant change in the peripapillary RNFL thickness, CMT, and optic nerve morphology in patients with diabetic retinopathy.     

Changes in Peripapillary Retinal Nerve Fiber Layer Thickness after Pattern Scanning Laser Photocoagulation in Patients with Diabetic Retinopathy

Purpose

To examine the effects of panretinal photocoagulation (PRP) using a pattern scanning laser (PASCAL) system on the retinal nerve fiber layer (RNFL) thickness in patients with diabetic retinopathy.

Methods

This retrospective study included 105 eyes with diabetic retinopathy, which consisted of three groups: the PASCAL group that underwent PRP with the PASCAL method (33 eyes), the conventional group that underwent conventional PRP treatment (34 eyes), and the control group that did not receive PRP (38 eyes). The peripapillary RNFL thickness was measured by optical coherence tomography before, six months, and one year after PRP to evaluate the changes in peripapillary RNFL.

Results

The RNFL thickness in the PASCAL group did not show a significant difference after six months (average 3.7 times, p = 0.15) or one year after the PRP (average 3.7 times, p = 0.086), whereas that in the conventional group decreased significantly after six months (average 3.4 times, p < 0.001) and one year after PRP (average 3.4 times, p < 0.001).

Conclusions

The results of this study suggest that the PASCAL system may protect against RNFL loss by using less energy than conventional PRP.     

中度非增殖期糖尿病视网膜病变个体化激光光凝术应用分析

目的 探讨以FFA(眼底血管荧光造影)计算机图像信息为引导进行早期糖尿病视网膜病变个体化激光光凝术对视网膜功能的影响.方法 筛选出符合中度非增殖期糖尿病视网膜病变患者60例(110只眼),根据激光治疗的方式不同随机分成两组,以FFA计算机信息为引导个体化治疗组(实验组)和传统FFA图片下行全视网膜光凝治疗组(对照组),每组30例;随访24周.激光治疗后主要临床观察指标:术后视野光敏度变化、黄斑水肿、中心视力、毛细血管无灌注区、微血管瘤及新生血管等,以视网膜光敏度变化评价视网膜损害程度.结果 两组术后视网膜光敏度下降,实验组下降(1.23±0.47)Db,对照组下降(2.88±0.68)Db,下降程度试验组明显低于对照组(P＜0.05);与激光术前相比实验组差异无统计学意义(P＞0.05),对照组差异有统计学意义(P＜0.05).随访24周,持续性黄斑水肿8眼其中实验组3眼,对照组5眼;中心视力改变、毛细血管无灌注区、微血管瘤消退、新生血管等两组差异均无统计学意义(P＞0.05).结论 个体化激光治疗方案能有效达到视网膜光凝治疗目的,而视网膜功能损伤明显小于全视网膜光凝治疗组;应用个体化激光治疗方案短期内无明显增加中度非增殖期糖尿病视网膜病变视力丧失和其他并发症的风险.

Abstract：

Objective To explore the effects of retinal function with individualized diabetic retinopathy laser photocoagulation which guided by the FFA (Fundus fluorescein angiography) computer image information. Methods Sixty cases (110eyes) with indications of laser therapy moderate non-proliferative diabetic retinopathy according to the different methods were randomly divided into two groups, each group had 30 cases. Individualized laser photocoagulation with guided by the FFA computer image information was performed on the experimental group and pan retinal photocoagulation (PRP) by the traditional FFA image was performed on the control group. The follow-up was 24 weeks. Evaluation of degree of retinal damage was performed by retinal light sensitivity changes. Results Retinal light sensitivity was reduced by laser photocoagulation in the experimental group and control group. It was significantly lower in the experimental group that decreased 1.23± 0.47dB than in the control group (P＜0.05) that decreased 2.88± 0.68 dB. There was no significant difference on macular edema, neovascularization, visual acuity, capillary nonperfusion, postoperative complications between two groups in follow-up (P＞0.05). Conclusions Individual methods can effectively achieve the purpose of retinal laser photocoagulation therapy and the retinal dysfunction significantly less than the PRP group. Application of individualized laser photocoagulation treatments has no significant increase the risk of visual loss and other complications in the short term in moderate nonproliferative diabetic retinopathy.     

Associations Between Peripapillary Retinal Nerve Fiber Layer and Choroidal Thickness With the Development and Progression of Diabetic Retinopathy

PurposeTo evaluate the role of the peripapillary retinal nerve fiber layer (pRNFL) and peripapillary choroidal thickness (pCT) in the development and progression of diabetic retinopathy (DR).MethodsThis is a cohort study based on the baseline and 2-year follow-up data of the Guangzhou Diabetic Eye Study. Patients with type 2 diabetes mellitus between the ages of 30 and 80 years were recruited from communities in Guangzhou. DR was graded by seven-field fundus photography after dilation of the pupil. pRNFL and pCT were measured via swept-source optical coherence tomography.ResultsA total of 895 patients were included in the study; of these, 748 did not have DR at baseline and 147 had DR at baseline. During the 2-year follow-up, 80 developed DR (10.7%), and 11 experienced DR progression (7.5%). After adjusting for confounding factors, a higher risk of incident DR was strongly associated with a lower average thickness of the pRNFL (risk ratio [RR] per 1 SD, 0.55; 95% confidence interval [CI], 0.42–0.72; P < 0.001) and average pCT (RR per 1 SD, 0.49; 95% CI, 0.34–0.70; P < 0.001). Adding both metrics to the DR prediction model significantly improved the discriminant ability of the model for incidences of DR (area under the curve increased by 15.38% from 0.673 to 0.777; P < 0.001).ConclusionsNeurodegeneration shown by the thinning of pRNFL and impaired choroidal circulation shown by the thinning of pCT are independently associated with DR onset, and assessing both metrics can improve the risk assessment for DR incidences.     

Sight-threatening Diabetic Retinopathy at Presentation to Screening Services in Fiji

Purpose: To report the spectrum of retinopathy at first presentation to photoscreening services, to determine the proportion of patients that present with sight-threatening diabetic retinopathy (STDR), and to raise awareness of the burden of diabetic eye disease in Fiji.

Methods: This retrospective observational cohort study used data from the initial visit of all new patients presenting to the diabetes retinal screening service at the Pacific Eye Institute in Fiji over the 3-month period between July and September 2012. Patients were assessed using a detailed questionnaire regarding diabetes type, duration of disease, medications, complications and co-morbidities, and blood sugar control. Patients subsequently underwent non-mydriatic fundus photography according to Pacific diabetes retinal screening guidelines. Images were graded at the time of acquisition, and data were entered onto a computerized database. For the purposes of this study, information regarding retinopathy grading, visual acuity and patient demographics was used.

Results: A total of 522 new patients were screened over the 3-month period. STDR was observed in 27% of patients, with 15% observed to have bilateral STDR. Diabetes control was generally poor. Blindness and visual impairment were observed in 2.7% and 6.7% of the cohort, respectively.

Conclusion: Severe and advanced diabetic retinopathy was present in this population presenting to screening. This was observed 4 years after the formal expansion of the screening services and reflects the high prevalence of diabetes in the population. The need for increased public awareness and greater resource allocation into diabetes and its complications is emphasized.     

蚕食式膜切除术在糖尿病视网膜病变中的应用

目的:从术中术后并发症的发生率评价蚕食式膜切除术在糖尿病视网膜病变中的作用。方法:对比分析了行普通撕膜技术的31例(34只眼)和行蚕食式膜切除术的52例(58只眼)术中术后并发症的发生率。结果:蚕食式膜切除术组发生医源性视网膜裂孔2只眼,普通手术组7例(P<0.05);蚕食式膜切除术组术中出血4只眼,普通手术组15只眼(P<0.01);蚕食式膜切除术组术后有6只眼发生Ⅲ级反应,普通手术组有5只眼(P>0.05)。结论:糖尿病视网膜病变中使用蚕食式膜切除术剥膜比较安全,能减少手术中及手术后并发症。     

激光治疗糖尿病视网膜病变的疗效观察

目的 探讨激光治疗糖尿病视网膜病变的效果.方法 根据DRPSG(Diabetic Retinopathy Photocoagulation Study Group)制定的治疗技术规定,对280例365只眼分别为增殖前期糖尿病视网膜病变(Preproliferative diabetic retinopathy,PPDR)、增殖期糖尿病视网膜病变(Proliferative diabetic retinopathy,PDR)及糖尿病性黄斑水肿(Diabetic macular edema,DME)患者,分别行标准全视网膜光凝(S-PRP)、超全视网膜光凝(E-PRP)、局限或格栅光凝.术后3、6、12个月行FFA及彩色眼底像,新生血管未消退者和无灌注区尚存者追加光凝,随访3～36个月.结果 355只眼行全视网膜光凝,新生血管或无灌注区全部或部分消退256只眼,有效率为72.1%:视力不变和增进292只眼,占82.3%;35只黄斑水肿眼局限或格栅光凝后,26只眼水肿减轻或消失,有效率74.3%.结论 激光治疗糖尿病性视网膜病变安全有效.     

氪红激光凝治疗增殖型糖尿病性视网膜病变

目的;观察氪红激光光凝治疗增殖型糖尿病性视网膜病变的疗效。方法：对患有增殖型糖尿病性视网膜病变伴有屈光间质混浊或轻度玻璃体积血的147例209眼进行了氪红激光全视网膜光凝治疗。结果：患者治疗前和治疗后视力无明显差异（P＞0．05）。全视网膜光凝术后视盘和视网膜的新生血管部分消退。结论：氪激光光凝对于那些氩激光无法治疗的伴有屈光间质混浊或轻度玻璃体积血的增殖型糖尿病性视网膜病变是有效的治疗方法,可使新生血管消退,有效地防止再出血的发生。     

Photocoagulation Treatment of Proliferative Diabetic Retinopathy: Clinical Application of Diabetic Retinopathy Study (DRS) Findings,DRS Report Number 8

Additional follow-up confirms previous reports^1–4 from the Diabetic Retinopathy Study (DRS) that photocoagulation, as used in the study, reduces the risk of severe visual loss by 50% or more. Decreases of visual acuity of one or more lines and constriction of peripheral visual field due to treatment were also observed in some eyes. These harmful effects were more frequent and more severe following the DRS xenon technique.^3,4 The two-year risk of severe visual loss without treatment outweighs the risk of harmful treatment effects for two groups of eyes: (1) eyes with new vessels and preretinal or vitreous hemorrhage; and (2) eyes with new vessels on or within one disc diameter of the optic disc (NVD) equaling or exceeding 1/4 to 1/3 disc area in extent, (Fig 1), even in the absence of preretinal or vitreous hemorrhage. For eyes with these characteristics, prompt treatment is usually advisable. For eyes with less severe retinopathy, DRS findings do not provide a clear choice between prompt treatment or deferral unless progression to these more severe stages occurs.     

Panrefinal Photocoagulation Influence on Vitrectomy Results for Complications of Diabetic Retinopathy

Despite panretinal photocoagulation (PRP), some diabetic eyes develop complications that are correctable with vitrectomy. The results of vitrectomy performed on 80 eyes having previtrectomy PRP are compared with 402 eyes without photocoagulation. The preoperative findings and operative procedures were almost identical, except the PRP cases had a slightly higher incidence of preoperative iris rubeosis and traction macular detachments, and more surgical membrane peeling. Six months after vitrectomy, the PRP eyes had slightly better visual acuities and fewer detached maculas, but were otherwise almost identical to the non-photocoagulated eyes. There was no evidence that pre-vitrectomy PRP prevents postoperative iris rubeosis.     

Overview of Epidemiologic Studies of Diabetic Retinopathy

Diabetic retinopathy has been an important cause of blindness in young and middle age adults in the United States. Epidemiologic studies have quantitated the risk and have described potentially causal factors associated with many ocular complications of diabetes and other facets of this disease. A review of recent advances in diagnosis, treatment, temporal trends, and health care for diabetic retinopathy was conducted. Since the early 1980's, there have been studies of the variability of diabetic retinopathy in populations around the world and subpopulations in the United States which have demonstrated the high prevalences and incidences of this condition. Observational studies and clinical trials have documented the importance of glycemic and blood pressure control in the development and progression of this disease. There are some differences in the importance of confounders in different populations. Epidemiologic data have helped understand the importance of health care and health education in prevention and treatment of this condition. Observational studies have documented the importance of this disease on quality of life. Although there have been advances in understanding the distribution, causes, and severity of diabetic retinopathy, this is ever changing and requires continued monitoring. This is important because the increasing burden of diabetes will place a greater burden on the population and the medical care systems that will be caring for them.     

Diabetic Retinopathy Risk Factors: Plasma Erythropoietin as a Risk Factor for Proliferative Diabetic Retinopathy

Purpose

The purpose of this study was to evaluate whether any stage of diabetic retinopathy (DR) is associated with levels of plasma erythropoietin and other plasma parameters.

Methods

It was examined a representative sample of 180 type 2 diabetes patients aged 40 to 79 years. Ophthalmic examination including a funduscopic examination, performed by an experienced ophthalmologist and the retinal finding were classified according to the grading system for diabetic retinopathy of ETDRS (Early Treatment Diabetic Retinopathy Study). It was measured the levels of plasma erythropoietin, cholesterol, triglyceride, apolipoproteins A and B, C-reactive protein, fasting blood glucose and hemoglobin A1C (HbA1C) in 88 DR patients and 92 controls without DR. Risk factors correlated with DR were compared between groups.

Results

The study group of 180 patients included 72 males and 108 females. The mean age of the patients with and without DR was 57.36 ± 8.87 years and 55.33 ± 8.28 years, respectively. Of the 88 patients with DR, only 9 (10%) had proliferative DR and the rest suffered from non-proliferative DR. The mean plasma levels of erythropoietin in proliferative DR group showed a significant difference in comparison to other groups. The mean plasma levels of cholesterol, triglyceride, apolipoproteins A and B, C-reactive protein, and fasting blood glucose were not significantly different in the three groups except for HbA1C. The absolute relative risk (ARR) also showed that erythropoietin was an increasing risk for proliferative DR (ARR, 1.17; 95% confidence interval, 1.060 to 1.420; odds ratio,1.060).

Conclusions

Of the factors studied, erythropoietin level showed significant increase in proliferative DR group. The stepwise raised in mean plasma erythropoietin level which demonstrates significant correlation with proliferative DR versus remaining two groups, will be an indication of its role in proliferative DR.     

糖尿病视网膜病变光凝术的并发症与处理

目的 探讨糖尿病视网膜病变(DR)光凝术常见与少见严重并发症的发生机制及处理方法.方法 对PPDR、早期PDR、高危PDR患者77例132只眼,实施次全、标准及超全视网膜光凝,有临床意义的黄斑水肿则联合局部光凝.观察术中、术后3个月内并发症的发生并给予相应处理.结果(1)55只眼(41.67%)无并发症发生,病情稳定.(2)29只眼(21.97%)刺、胀痛,多可以忍受,未作特殊处理.(3)16只眼(12.12%)中心视力下降,其中9只眼为黄斑水肿加重,5只眼为调节性视力下降,2眼白内障加重.对有临床意义的黄斑水肿先行局部光凝、延长光凝间隔时间及服用一些中药,有利于黄斑水肿消退.(4)10只眼(7.58%)玻璃体出血,其中2只眼行激光追加;6只眼行玻切手术;2只眼放弃治疗;(5)9只眼(6.82%)感幌眼不能视物,20min内恢复.(6)4只眼(3.03%)急性结膜,加强消毒杀菌可杜绝;3眼(2.27%)急性眼压、血压升高并光感消失,对症急救后视力恢复;1眼睫状体脉络膜水肿伴前房消失,后期瞳孔后粘连,继发青光眼;另有1单眼患者等待光凝术时发生低血糖性短暂晕厥,给予低血糖抢救后好转.结论 熟练掌握DR光凝术的技术特点,通晓各种并发症的发生机制和处理原则;严格无菌操作;熟悉患者眼前后节及全身病情;准确判定和快速处理有助于减少严重后果的发生.     

Retinal Sensitivity Correlates With the Superficial Vessel Density and Inner Layer Thickness in Diabetic Retinopathy

PurposeThe purpose of this paper was to present our study on the relationship between the parafoveal sensitivity measured using microperimetry and the vessel density (VD) assessed by optical coherence tomography-angiography (OCT-A) in eyes with diabetic retinopathy (DR).MethodsThe observational case series was conducted in a tertiary ophthalmology center. Eyes with DR and without macular edema were consecutively included. All eyes underwent microperimetry and OCT-A. The correlation between the regional retinal sensitivity and the corresponding local capillary changes and structural alterations seen on OCT-A was assessed in each retinal quadrant.ResultsThirty-seven eyes of 21 patients were included. The mean retinal sensitivity was 28.7 ± 2 decibel (dB). The mean parafoveal VD was 43.2 ± 4.2% in the superficial capillary plexus (SCP) and 48.1 ± 3.3% in the deep capillary complex (DCC). In the multivariate linear regression model, the mean retinal sensitivity was positively correlated with the VD in the SCP in the parafoveal ring (P = 0.01) and with the inner nuclear layer (INL) thickness (P = 0.01). The qualitative analysis of each quadrant showed the presence of areas of capillary dropout with a normal sensitivity. Conversely, all areas of decreased sensitivity (<25 dB) were associated with a decreased VD in the SCP and the DCC.ConclusionsThe parafoveal sensitivity positively correlated with the VD in the SCP in DR eyes. Areas with a low retinal sensitivity were always co-located with a loss of capillaries in the SCP and the DCC despite preserved outer retinal layers.     

Vitrectomy in the Management of Diabetic Retinopathy

According to the Early Treatment Diabetic Retinopathy Study, at least 5% of eyes receiving optimal medical treatment will still have progressive retinopathy that requires laser treatment and pars plana vitrectomy. During the past decade, improvements in instrumentation and surgical techniques have allowed more difficult cases of diabetic retinopathy to be candidates for vitrectomy. However, although the thresholds for performing surgery within established indicated situations have been lowered, only a few additional indications have been established. Although vitrectomy improves the prognosis for a favorable visual outcome, preventive measures, such as improved control of glucose levels and timely application of panretinal photocoagulation, produce better results. The authors review the indications, techniques, and results of vitrectomy in the management of diabetic retinopathy.     

Ultrawide-field Fluorescein Angiography for Evaluation of Diabetic Retinopathy

Purpose

To investigate the advantages of ultrawide-field fluorescein angiography (FA) over the standard fundus examination in the evaluation of diabetic retinopathy (DR).

Methods

Ultrawide-field FAs were obtained in 118 eyes of 59 diabetic patients; 11 eyes with no DR, 71 eyes with nonproliferative diabetic retinopathy (NPDR), and 36 eyes with proliferative diabetic retinopathy (PDR), diagnosed by the standard method. The presence of peripheral abnormal lesions beyond the standard seven fields was examined.

Results

Ultrawide-field FA images demonstrated peripheral microaneurysms in six (54.5%) of 11 eyes with no DR and all eyes with moderate to severe NPDR and PDR. Peripheral retinal neovascularizations were detected in three (4.2%) of 71 eyes with NPDR and in 13 (36.1%) of 36 eyes with PDR. Peripheral vascular nonperfusion and vascular leakage were found in two-thirds of eyes with severe NPDR and PDR.

Conclusions

Ultrawide-field FA demonstrates peripheral lesions beyond standard fields, which can allow early detection and a close evaluation of DR.     

Genetics of Diabetic Retinopathy

Abstract

Multiple studies have shown that genetic factors may play an important role in determining an individual’s risk for the development of diabetic retinopathy (DR) and progression to proliferative DR. However, consistent and definitive genetic associations with DR across broad populations have been not been established. Numerous genes have been studied for their association with DR and the results of these investigations have most specifically pointed to three specific genes that are likely involved in DR development and progression. The gene coding for vascular endothelial growth factor, aldose reductase, and the receptor for advanced glycation end products have been extensively evaluated, and specific polymorphisms of these genes have been suggested to potentially increase the risk of DR development. In this paper, we have reviewed the published literature on the genetics of DR and the potential implications for DR development and progression.     

视网膜激光治疗糖尿病性视网膜病变的临床观察

目的观察倍频532nm激光视网膜光凝术治疗糖尿病性视网膜病（DR）的疗效。方法用倍频532nm激光对298例（568只眼）增生前期和增生早期DR患者进行视网膜光凝治疗。光凝3～6次,术后平均随访9个月。结果治疗后182只眼（32%）视力提高,视力无变化352只眼（62%）,视力下降34只眼（6%）。随病变程度增加疗效降低（P〈0.01）。荧光素眼底血管造影（FFA）及相干光断层扫描（OCT）检查,有黄斑水肿的272只眼中,光凝后水肿完全消退者142只眼（52%）,部分消退者122只眼（45%）,不变者82只眼（3%）。结论倍频532nm激光视网膜光凝术治疗DR有效,在增生前期治疗效果好。     

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。