Retrobulbar Anesthesia and Retinal Vascular Obstruction

The cases of three patients who developed combined central retinal artery/vein obstruction secondary to retrobulbar anesthesia are presented. In one case the obstruction was presumably present immediately after surgery, while in the other two it was observed to evolve over a period of several days. A dilated optic nerve sheath was demonstrated by contact B-scan ultrasonography in two cases and by computerized tomography in the third case, suggesting intravaginal sheath hemorrhage as a common underlying pathophysiologic process. Partial return of vision was evident in the latter case following orbitotomy with optic nerve sheath decompression.     

Central Retinal Artery Obstruction and Visual Acuity

The records of 72 patients (73 eyes) with acute central retinal arterial obstruction (CRAO) were reviewed. Three eyes (4%) were initially observed to have no light perception vision. However, two of these three were found to have concomitant posterior ciliary circulation defects on fluorescein angiography, and the third had electroretinographic evidence of both outer and inner retinal damage. Previous studies have indicated that a much higher percentage of patients with CRAO present with NLP vision. From the data presented it is the feeling of the authors that cases with obstruction of the central retinal artery alone and NLP acuity in the involved eye are most unusual. If true NLP vision is present, additional complicating factors should be suspected, particularly abnormalities of the choroidal circulation and the optic nerve.     

Neovascular glaucoma following central retinal vein obstruction

The results of a prospective clinical and fluorescein angiographic study of 155 patients with central retinal vein obstruction (CRVO) were analyzed to identify risk factors contributing to the subsequent development of iris neovascularization (NVI) and neovascular glaucoma (NVG). Of 144 untreated eyes, 20% developed NVG. The eyes were classified as having either an ischemic or a hyperpermeable type of CRVO according to the extent of retinal capillary nonperfusion demonstrated by the initial fluorescein angiogram. The risk of developing NVG was found to be approximately 60% in those eyes with extensive retinal ischemia. None of the 22 eyes with an ischemic CRVO treated with panretinal photocoagulation (PRP) prior to the onset of NVI developed NVG.     

Central retinal vein obstruction and carotid artery disease

Thirty-seven consecutive patients (39 eyes) with a central retinal vein obstruction (CRVO) were studied in a cross-sectional fashion with intravenous fluorescein angiography and digitial subtraction carotid angiography. Among the 35 patients (37 eyes) with acceptable studies, 24 eyes, (64%) had an ischemic CRVO, 12 (33%) demonstrated a nonischemic CRVO, and one (3%) was indeterminate. A 17% incidence of ipsilateral atherosclerotic carotid artery obstruction greater than or equal to 50% was associated with both the ischemic (4/24 eyes) and nonischemic (2/12 eyes) groups. Overall, 13 of 35 (37%) patients with CRVO had demonstrable common or internal carotid artery atherosclerosis, an incidence no higher than found in a historical control sample studied postmortem. However, this incidence rose to 50% in patients with an ischemic CRVO and decreased to 17% in those with the nonischemic variety.     

Retinal ischemia and risk of neovascularization following central retinal vein obstruction

The predominant risk factor for the development of neovascular complications involving the retina (NVR), the optic disc (NVD), and iris (NVI) following central retinal vein obstruction (CRVO) is the extent, location, and duration of retinal ischemia (ischemic drive). The extent of retinal capillary nonperfusion (ischemic index) was quantitated by microcomputer analysis of 200 standard fundus-iris fluorescein angiograms. The results were correlated with the development of neovascularization in eyes not receiving prophylactic argon laser panretinal photocoagulation (PRP). Of the 85 eyes with intact capillary perfusion (hyperpermeable group), none developed NVR/NVD and only one eye (1%) developed neovascular glaucoma (NVG). Twenty-nine eyes exhibited moderate degrees of retinal ischemia (indeterminate group), and three eyes (10%) developed NVR/NVD, with two eyes (7%) developing NVG. Of the 86 eyes with extensive retinal capillary nonperfusion (ischemic group), 28 eyes (33%) developed NVR/NVD and NVG occurred in 39 eyes (45%). The inherent difficulties in following high risk patients clinically and angiographically at frequent intervals over extended periods of time, the tendency for rapid progression of early NVI to NVG, and the relatively poor results following treatment in advanced cases make the early recognition of eyes at high risk to develop NVG essential and the initiation of prophylactic PRP as the treatment of choice in this disorder.     

Effects of argon laser photocoagulation on rubeosis iridis and angle neovascularization

Of 93 eyes with proliferative diabetic retinopathy treated by argon laser panretinal photocoagulation, two (2.2%) developed rubeosis. The incidence of rubeosis in five xenon-treated eyes was one (1.9%) and in an untreated group of 52 eyes, two (3.8%) developed rubeosis. The incidence of rubeosis in central retinal vein occlusion demonstrating retinal ischemia on fluorescein angiography was 60%, while in patients with central retinal vein occlusion and good capillary perfusion, the incidence of rubeosis only 1%. Panretinal photocoagulation was more effective in controlling rubeosis in diabetics than in patients with central retinal vein occlusion.     

A randomised prospective study of outpatient haemodilution for central retinal vein obstruction

Purpose: Central retinal vein obstruction (CRVO) has significant visual morbidity. We prospectively evaluated an outpatient haemodilution (HD) regimen for CRVO.
Methods: We recruited 59 patients with CRVO of less than three months' duration and visual acuity (VA) worse than or equal to 6/9.5. Thirty patients underwent HD (packed cell volume of <0.35, 12 weeks); there were 29 controls and follow-up was for six months.
Results: Incidence rates for VA improvement ( P =0.708) and rubeosis iridis ( P =0.619) between the two groups were not different. The incidence rate of VA deterioration was 5.315 times higher with HD ( P =0.035, Cox Proportional analysis).
Conclusion: This data does not support the previous studies on haemodilution.     

Digital subtraction carotid angiography and retinal arterial obstruction

Thirty-one consecutive patients with retinal arterial obstruction were studied with digital subtraction angiography (DSA). Among the 29 patients in whom DSA was technically acceptable, 45% (13/29) demonstrated evidence of carotid stenosis or an atherosclerotic plaque ipsilateral to the eye with the retinal arterial obstruction. In 21% of cases (6/29 patients) the stenosis was 60% or greater. The incidences of carotid atherosclerosis were similar among the central and branch retinal arterial groups.     

Efficacy of Panretinal Photocoagulation in Preventing Neovascular Glaucoma Following Ischemic Central Retinal Vein Obstruction

Ninety-three percent of eyes that develop neovascular glaucoma (NVG) following central retinal vein obstruction (CRVO) have an ischemic index greater than 50%. An ischemic index (percentage of retinal capillary nonperfusion) of 50% represents approximately 10 disc areas of retinal ischemia as determined by computer analysis of standard 30° fluorescein angiograms. The difficulties of following patients clinically and angiographically at frequent intervals over extended periods of time, and the tendency for iris neovascularization (NVI) to develop and to progress rapidly to NVG with painful loss of vision emphasizes the importance of early recognition and treatment of high-risk eyes. In this prospective study (1976–81), 100 consecutive eyes with an ischemic CRVO pattern (average ischemic index 82%) received early argon laser panretinal photocoagulation (PRP) and none developed NVG unless another ischemic event occurred following treatment. Prophylactic PRP in high-risk ischemic CRVO eyes appears to eliminate virtually the devastating complications of NVG.     

The venous closing pressure in central retinal vein obstruction

Objective: To assess the rate of change in the central retinal venous closing pressure in central retinal vein obstruction over time, and its relationship to visual acuity improvement and the development of rubeosis iridis.
Methods: Fifty patients presenting with central retinal vein obstruction of less than three months' duration, between the ages of 40 and 80 years, were reviewed prospectively. The central retinal venous closing pressure was measured by digital ocular compression. Patients were discharged from the study after the six-month visit.
Results: All patients had elevated venous closing pressure at presentation, whereas at six months only 24 patients had persistent elevation. Of 16 patients with lowering of the venous closing pressure within four months of onset of central retinal vein obstruction, 11 (69%) had two or more lines of visual acuity improvement. Only two of 10 patients (20%) developing lowering of the venous closing pressure thereafter had visual improvement. No patient developed rubeosis iridis after the venous closing pressure lowered.
Conclusion: The central retinal venous closing pressure is raised in central retinal vein obstruction to about central retinal arterial diastolic pressure, and is its pathognomonic sign. This sign is easily elicited via digital pressure on the eyelid, and has prognostic significance for visual acuity improvement and the development of rubeosis iridis.     

Evaluation of a Patient with Central Retinal Vein Occlusion

Patients suffering a central retinal vein occlusion should be evaluated for conditions that promote and/or contribute to the formation of a thombosis in the central retinal vein. These conditions include alterations of blood flow, altered viscosity of the blood, abnormalities of coagulation, and abnormalities of vessel walls. Patients with either a partial or complete central retinal vein occlusion have similarities in the age of onset, associated systemic findings, and laboratory data. At the time of onset, 90% of patients are older than 50 years. Seventy-four percent of patients will have symptoms or signs of associated systemic vascular disease (ie, hypertension, arteriosclerotic heart disease, and diabetes mellitus.) The most common laboratory findings include elevated blood lipids, abnormalities of glucose tolerance testing, and abnormalities of protein chemistries. Evaluation should include both a complete ocular and medical examination with appropriate laboratory tests and special studies. Assessment of central retinal venous pressure may be helpful in identifying those patients who have a severe, complete thrombosis and are at significant risk to develop anterior segment neovascularization.     

The clinical features and associations of retinal emboli

A series of 207 patients with retinal emboli is presented with the ocular findings andsystemic associations examined. Emboli were most frequently single, unilateral, crystalline and involved the left eye. Emboli were most frequently observed at the major retinal vascular temporal arcades and posterior pole arterioles, with 40% seen at a bifurcation and 10% at an arteriovenous crossing. Non-crystalline emboli were more likelyto be associated with retinal pathology, such as retinal artery or vein occlusion. Carotid ultrasound was performed in 74 patients: 18% of asymptomatic subjects had internal or common carotid stenosis < 75%; 21% of symptomatic patients had stenosis >75%. In 70%, the stenosis was worse on the side of the embolus. In symptomatic patients, significant stenosis is more likely to be unilateral.     

The vitreomacular interface in retinal vein occlusion

Purpose: To evaluate the posterior vitreous adhesion status in patients with a history of central or branch retinal vein occlusion and to compare the results with the natural time‐course of posterior vitreous detachment in healthy age‐related controls. Methods: A retrospective chart review in terms of the posterior vitreous adhesion status was performed in 132 patients (133 eyes) with a history of a central (CRVO) or branch (BRVO) retinal vein occlusion. All patients underwent vitrectomy. Based on the operation reports, the vitreous adhesion status was classified as attached, partially detached or completely detached. The results were compared to the natural time‐course of posterior vitreous detachment development in healthy age‐related controls. Results: Eighty‐one eyes met the inclusion and exclusion criteria. Fifty‐two eyes (64%) had a history of CRVO and 29 eyes (36%) a history of BRVO, respectively. In the CRVO group, the posterior vitreous was attached in 47 eyes (90%) and completely detached in five eyes (10%). In the BRVO group, the posterior vitreous was attached in 27 eyes (93%), partially detached in 1 eye (3%) and completely detached in another eye (3%). A subdivision into age classes and a comparison with healthy age‐related controls [data by Weber‐Krause & Eckardt (1997) Ophthalmologe, 94, 619–623] showed in patients between 65 and 69 years of age an attached posterior vitreous cortex in 72% in healthy eyes, in 100% in CRVO (p = 0.109) and in 89% in BRVO (p = 0.440), in patients between 70 and 79 years of age an attached posterior vitreous cortex in 56% in healthy eyes, in 86% in CRVO (p = 0.010) and in 100% in BRVO (p = 0.038) and in patients between 80 and 89 years of age an attached posterior vitreous cortex in 43% in healthy eyes, in 100% in CRVO (p = 0.191) and in 67% in BRVO (p = 0.582) (Fisher’s exact t‐test). Conclusion: In patients with a history of CRVO or BRVO, the posterior vitreous cortex stays attached more frequently in all age groups in comparison with the healthy age‐related controls.     

FFA和OCT在诊断视网膜中央动静脉阻塞中的应用价值

目的：探讨荧光素眼底血管造影( fundus fluorescein angiography, FFA )、相干光断层扫描( optical coherent tomography,OCT)在诊断视网膜中央动静脉阻塞中的临床价值。
　　方法：对2012-06/2015-12本院眼科中心收集的47例47眼视网膜中央动静脉阻塞病例进行回顾性分析,根据临床最终确诊结果分为视网膜中央动脉阻塞( central retinal artery occlusion,CRAO)患者21眼、视网膜中央静脉阻塞( central retinal vein occlusion,CRVO)患者26眼,所有患者均于起病2 wk内接受了FFA和OCT检查,对两种检查结果的图像资料进行分析。
　　结果：CRAO组患者的平均黄斑中心小凹厚度、测量角度、充盈时间测定结果均显著低于CRVO组患者的平均值,差异均具有统计学意义(P<0.05)。
　　结论：视网膜中央动静脉阻塞的OCT、FFA图像各具特点,二者结合可以较好地鉴别诊断视网膜中央动静脉阻塞。     

视网膜中央静脉阻塞玻璃体积血合并原发性高血压的手术疗效

目的:分析视网膜中央静脉阻塞玻璃体积血合并原发性高血压的手术疗效.方法:回顾性分析2011-03/2015-03因玻璃体积血在我院行玻璃体切割的原发性高血压患者83例83眼,根据术中所见,其中有28眼玻璃体积血由视网膜中央静脉阻塞引起,术后随访9~36(平均22.4)mo.检查记录患者手术前后最佳矫正视力、术后并发症情况,并进行统计分析.结果:视网膜中央静脉阻塞玻璃体积血合并原发性高血压发生率为33.7%;术后最佳矫正视力3.3~4.5,术后最佳矫正视力提高24眼(86%),视力不变4眼(14%),无视力下降患者,手术前后视力相比差异有统计学意义(P<0.05);术后发生黄斑水肿5眼,发生率18%;所有患者术后均没有发生视网膜脱离及复发玻璃体积血.结论:手术治疗合并原发性高血压的视网膜中央静脉阻塞玻璃体积血疗效好,可减少并发症,提高视力.     

视网膜静脉阻塞眼底血流超声初步研究

目的：观察视网膜静脉阻塞患者视网膜中央血管系统的微循环变化。方法：运用超声多普勒技术对视网膜静脉阻塞患者47眼作视网膜中央动脉（CRA）和视网膜中央静脉（CRV）血流速度的检测。结果：患者CRA,CRV的血流速度下降明显（P＜0.01）,与眼别、年龄、性别无明显差别;舒张末期血流速度（EDV）、收缩期血流加速度（A）反应灵敏,早期 即有变化（P＜0.01）;收缩期峰值血流速度（PSV）下降则相对滞后;阻力指数（RI）变化不大。部分静脉郁滞性视网膜病变（VSR）患者的各测值以后均回升,而出血性网膜病变（HR）者却不变。早期综合治疗对部分VSR患者的预后有利。结论：血流速度超声检测指数敏感地反映了视网膜微循环情况,可作为病情、预后及疗效观察的参考依据。     

Assessment of the spontaneous pulsations of the central retinal vein in daily ophthalmic practice

The purpose of this study is to assess the frequency of eyes with a spontaneous pulsation of the central retinal vein in the setting of a busy daily ophthalmic practice. The clinical observational case-series study included 690 eyes (345 subjects). The optic disc was ophthalmoscopically assessed using a non-contact ophthalmoscopic lens at the slit lamp. Out of the study population, 526 eyes (76.2%) of 265 (76.8%) subjects showed a detected spontaneous pulsation of the central retinal vein (prevalence rate: 76.2 +/- 1.6% [mean +/- standard error] per eye, and 76.8 +/- 2.3% per subject). In univariate analysis, the presence of a detected spontaneous central retinal vein pulsations was statistically associated with systolic systemic blood pressure (P = 0.04) and with the ocular perfusion pressure (P = 0.03). The results suggest that as examined in the setting of a busy daily ophthalmic practice, the central retinal vein was found to show a spontaneous pulsation in about 80% of the subjects.     

Retinal vascular events after intravitreal bevacizumab

Acta Ophthalmol. 2010: 88: 730–735

Abstract.

Purpose: To record retinal vascular events following intravitreal bevacizumab injection. Methods: Collaborative multi‐centre retrospective case series. Results: Eight patients were documented to have central retinal artery occlusion (four patients), branch retinal artery occlusion, capillary occlusion, central retinal vein occlusion and branch retinal vein occlusion (one patient each) within 0–55 days (median 2 weeks) of intravitreal bevacizumab. All patients had several ocular and systemic risk factors for retinal vascular events: elevated intraocular pressure on discharge (four patients), pre‐existent glaucoma (one patient), pre‐existent ischaemic retinal vascular disorder (four patients), systemic hypertension (five patients), diabetes mellitus (three patients), coronary artery disease (four patients), carotid disease (three patients), smoking (two patients) and migraine (one patient). Conclusion: The retinal vascular events may be associated with the underlying ocular disease under treatment or with the underlying systemic disease, may be related to an increased intraocular pressure post‐injection constraining further an already poor retinal perfusion, the vasoconstrictor effect of bevacizumab, or a combination of all three.     

视网膜脱离巩膜扣带术后后极部视网膜定量分析

目的:研究视网膜脱离(retinal detachment,RD)巩膜扣带术后后极部视网膜水肿情况。方法:应用视网膜厚度分析仪(RTA)对38例38眼孔源性RD巩膜扣带术后手术成功眼后极部视网膜厚度进行测量。结果:术后进行RTA测量随访的时间为72.61±57.27d,经RTA测量,RD术后黄斑中心凹平均厚度168.03±38.27μm,与对侧眼比较二者差异无显著性(P>0.05);RD眼术后后极部平均厚度175.50±33.85μm,与对侧眼比较二者差异无显著性(P>0.05),RD眼术后后极部最大厚度(310.18±158.40μm)与对侧眼比较,二者差异有显著性(P<0.01)。结论:通过RTA可精确测量并观察后极部视网膜水肿发生情况,视网膜脱离巩膜扣带术后2mo后极部视网膜局限性水肿仍存在,术后这个时间患者仍存在视物变形与此有关,仍需进行进一步的长期随访观察后极部视网膜水肿消退的时间。而且,在这段时间内考虑给予相应的干预治疗,以改善视功能。     

基于深度学习的视网膜毛细血管无灌注区智能识别定量分析系统在CRVO缺血分型诊断中的应用

目的　探讨一种基于深度学习的视网膜毛细血管无灌注区（NPA）智能识别定量分析系统在视网膜中央静脉阻塞（CRVO）缺血分型诊断中的应用价值。方法　回顾性病例系列研究。选取2017年1月至2018年12月经山西省眼科医院门诊确诊为CRVO并行荧光素眼底血管造影（FFA）检查的343例343眼患者纳入本研究。随访并记录患者自发病起1年内是否发生新生血管并发症。应用人工智能诊断系统计算CRVO患者后极部55°视野范围NPA面积,受试者工作特征曲线（ROC）分析该NPA面积对CRVO发生新生血管并发症的诊断价值。结果　343例CRVO患眼中有26眼发生了新生血管并发症,发病率7.58%。依据NPA面积判断CRVO患者是否发生新生血管并发症的曲线下面积为0.889（95%CI:0.799~0.978,P<0.001）。最佳截断值为20.997视盘面积（DA）,灵敏度为0.808,26眼新生血管并发症患者中有21眼NPA值大于该值;特异度为0.946,317眼无并发症患者中有300眼NPA值小于该值。结论　基于深度学习的NPA智能识别定量分析系统可为CRVO分型诊断提供决策依据。55°视野范围后极部NPA>20 DA可作为CRVO缺血分型的阈值标准。