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At least 19 recordsLinked to original sources
PubMed2005

[Surgical approach to retinal vein occlusion].

Retinal vein occlusions are the second most common vision threatening retinal vascular disorders. Our therapeutic armamentarium for functional improvement was very limited in the past for all types of retinal vein occlusions (branch, central and hemi-central retinal vein occlusion). Also pathomechanism and risk factors are not completely understood yet. Argon-laser-photocoagulation can prevent the development and treat neovascularizations successfully, but is unable to improve visual function in most cases. Thrombolytic therapy applied systemically is limited due to serious side effects but may be helpful when injected intraocularly. Isovolemic hemodilution may be efficacious in central retinal vein occlusion (CRVO). The creation of a laser-induced chorioretinal venous anastomosis showed serious complications. Since 1999 numerous reports on successful surgical techniques were published. It could be shown that the dissection of the adventitial sheath with separation of the artery from the vein at the arteriovenous crossing where branch retinal vein occlusion occurs can re-establish the retinal blood flow with reduction of macular edema. But it is still unclear which step of the surgery (vitrectomy, ILM-peeling, sheathotomy) is causative for the results. A new surgical approach in CRVO is the radial optic neurotomy (RON). This technique was primarily performed under the hypothesis of decompression of the central vein by cutting the scleral ring. Meanwhile there is some evidence that the formation of chorioretinal shunts may be the decisive factor in cases of successfully performed RON. Due to inconsistent and rare data this surgical procedure needs further evaluation. Another surgical option is the cannulation of the occluded vein. This technique seems to be feasible but the clinical results still have to be proved. Despite several uncertainties and open questions, surgical techniques are likely to overcome the desolate therapeutic situation for retinal vein occlusion of the past.

Angioplasty, Balloon↗
PubMed1992

Retinal vein occlusion.

Retinal vein occlusion is a common form of retinal vascular disease, especially in middle-aged and older individuals. The diagnosis is based on the funduscopic finding of retinal vein dilatation in association with retinal hemorrhages and cotton-wool spots. The pathology can involve the entire venous system or can be limited to a branch of the central retinal vein. Retinal vein occlusion can be distinguished clinically from diabetic retinopathy and other retinal diseases. Treatment for the acute phase of retinal vein occlusion has been disappointing. However, some late complications, such as persistent macular edema and neovascularization of the iris and retina, respond well to retinal photocoagulation. The family physician has an important role in detecting and controlling risk factors for retinal vein occlusion, including hypertension, diabetes mellitus and hyperviscosity syndromes.

Adult↗
PubMed2002

Cardiovascular and thrombophilic risk factors for central retinal vein occlusion.

Retinal vein occlusion (RVO) is a relatively common disease that is often associated with a variety of systemic disorders including arterial hypertension, diabetes mellitus, dyslipidemia, and systemic vasculitis. There are various types of RVO, categorized on the basis of the site of occlusion and on the type of consequent vascular damage. Central retinal vein occlusion (CRVO) is the most frequently occurring and clinically relevant type of RVO. In addition to the well-known classical risk factors, new hemostasis-related ones have been investigated in patients affected by CRVO. The data concerning a number of parameters remain contradictory; yet, high levels of type 1 plasminogen activator inhibitor (PAI-1) and hyperhomocysteinemia appear to play a significant role in the pathogenesis of this disease. Although based on a limited number of studies, this new knowledge could eventually provide important indications regarding prognosis and therapeutic strategies.

Journal Article↗
PubMedDate not supplied

Management of retinal vein occlusion.

Retinal vein occlusion is a common cause of visual loss. The clinical features, pathogenesis, aetiology and management of this condition are presented and discussed. It is an advantage to involve both the physician and the ophthalmologist in the management of the condition.

Comorbidity↗
PubMedDate not supplied

Does type II diabetes predispose to retinal vein occlusion?

Retinal vein occlusion (RVO) not infrequently occurs in diabetic patients. Although the aetiology is unclear, it could relate to the other microvascular complications of diabetes. In the non-diabetic, both the central (CRVO) and branch (BRVO) forms are commonly associated with hypertension and hyperlipidaemia. We have therefore studied fifty type II diabetic patients with RVO compared to a carefully matched diabetic control group (n = 50) to elucidate underlying medical conditions and hence the aetiology of RVO in diabetic patients. The two groups were well matched. Diabetics with RVO showed a strikingly high prevalence of hypertension compared to the controls (72% versus 32%: p < 0.001) and a trend to increased hyperlipidaemia (54% versus 36%). Diabetic microvascular complications were more common in the control group (diabetic retinopathy and proteinuria). No significant differences were observed in mean HbA1 or weight, but current smoking habits and blood pressure levels were increased in the diabetics with RVO. 80% of diabetic patients with the BRVO form, were hypertensive. We conclude that the main underlying medical conditions for RVO in diabetics are hypertension and hyperlipidaemia, and these may be important in the aetiology as in the non-diabetic. RVO is more common in type II rather than type I diabetes, and does not associate with the presence of diabetic microvascular complications. Clinical assessment for hypertension and hyperlipidaemia is therefore important in diabetic patients with RVO, especially if recurrence of the condition and further visual loss is to be prevented.

Adult↗
PubMed1997

Sex hormone preparations and retinal vein occlusion.

Retinal vein occlusion (RVO) is most commonly seen in middle-aged or older patients and is associated with underlying cardiovascular risk factors. It is much less common in younger patients. Use of the oral contraceptive pill (OCP) is known to be a risk factor for cardiovascular and cerebrovascular disease. There have previously been a few isolated case reports of patients sustaining an RVO whilst taking the OCP. The aim of this study was to investigate patients sustaining an RVO whilst taking the OCP or hormone replacement therapy (HRT). From a large series of 588 patients, we found 11 with an RVO associated with sex hormone preparations. Of these, 6 had taken the OCP and 5 were HRT users. From this large group there were only 9 female patients aged under 35 years who sustained an RVO. Of these, 6 were associated with use of the OCP. All patients were investigated for recognised medical risk factors for RVO. None of these factors were identified in the patients who had used the OCP. Of the patients taking HRT, 4 of the 5 had other potential risk factors. From our large series, the prevalence of RVO in female patients under 35 years taking the OCP was 66%. There is a 30% uptake of the OCP in the general population. These data support the view that RVO is a contraindication to the use of the OCP. Additionally, it would appear (albeit from limited data) that patients who sustain RVO may continue with their HRT, as HRT is not a major single risk factor for RVO.

Adult↗
PubMed2003

The platelet glycoprotein Ia/IIa gene polymorphism C807T/G873A: a novel risk factor for retinal vein occlusion.

Retinal vein occlusion (RVO) is associated with hyperhomocysteinaemia and the antiphospholipid syndrome-disorders known to contribute to both arterial and venous thrombosis. In both of these conditions and RVO, platelet activation occurs. Aspirin, not warfarin, is the most effective antithrombotic agent in RVO and, taken together, these observations suggest an important role for platelets in this common ocular thrombotic condition. Platelet glycoprotein Ia/IIa (GpIa/IIa) is an adhesion molecule mediating platelet-collagen interactions and is key to the initiation of thrombosis. Recently, the cellular density of this molecule was shown to be determined by two silent, linked polymorphisms (C807T/G873A) within the GpIa/IIa gene. There is evidence that some of the resulting genotypes are associated with thrombo-embolic disease. This study therefore aimed to establish the prevalence of the GpIa/IIa polymorphisms and the three commonest hereditary thrombophilic disorders (prothrombin gene G20210A (PT) mutation, Factor V Leiden (FVL), and the thermolabile methylene tetrahydrofolate reductase C677T (MTHFR) mutation) in patients with RVO and normal controls. The GpIa/IIa polymorphisms and thrombophilic abnormalities were all identified using the polymerase chain reaction.Our results show that the frequency of the GpIa/IIa polymorphisms was similar in our normal control population to previously published series. Patients with RVO, however, had only a 10% (4/40) frequency of the lowest risk subtype (CC/GG) compared to 37.5% (15/40) in the control group-P 0.0039. The incidence of the PT, FVL, and MTHFR thrombophilic mutations was not different between the two groups, but interestingly none of the 7/40 RVO cases with a PT, FVL, or MTHFR mutation had the low-risk GpIa/IIa genotype while all but one of the controls did-P<0.05. Thus, 17.5% of RVO patients harboured more than one prothrombotic abnormality. The principal difference between the RVO and control group was the very high incidence of the intermediate-risk GpIa/IIa subtype (CT/GA)-82.5 vs 50%, P&<0.05. These results suggest a major role for GpIa/IIa polymorphisms in the pathogenesis of RVO.

Adult↗
PubMed2001

Surgical posterior vitreous detachment combined with gas/air tamponade for treating macular edema associated with branch retinal vein occlusion: retinal tomography and visual outcome.

PURPOSE: To assess the effectiveness of surgical posterior vitreous detachment (PVD) together with gas/air tamponade in treating visual impairment from macular edema associated with branch retinal vein occlusion (BRVO-macular edema). METHODS: A cohort study was conducted. To treat visual disturbance caused by BRVO-macular edema in 19 consecutive patients at a University Hospital, phacoemulsification, intraocular lens implantation, and vitrectomy were performed, together with gas/air tamponade. Patients were followed up postoperatively for 3-18 months. Foveal structure was defined using optical coherence tomography (OCT). Preoperative visual acuity, central retinal thickness, and interval between BRVO onset and operation were compared between patients with postoperative visual improvement and those without improvement. RESULTS: Ten patients recovered normal or near-normal foveal configuration, while nine patients did not. Mean postoperative visual acuity in the former group of patients was significantly higher than in the latter. Mean foveal retinal thickness decreased significantly after the operation. The interval from onset of BRVO until operation was significantly shorter in patients with improved postoperative vision than in other patients, and patients operated on within 11 months had significantly increased postoperative visual acuity. CONCLUSIONS: Surgical PVD and gas/air tamponade appears effective in treating BRVO-macular edema, although relatively short duration from disease onset until operation is critical for improvement of vision. When a good postoperative foveal contour is seen, it seems to be associated with better visual outcome.

Adult↗
PubMed1989

[Role of the vitreous in retinal neovascularization evaluated by a comparison of central retinal vein occlusion and branch retinal vein occlusion].

Thirty three patients (33 eyes) with central retinal vein occlusion (CRVO) and 80 patients (81 eyes) with branch retinal vein occlusion (BRVO) were studied in an attempt to investigate the role of the vitreous in the formation of retinal neovascularization. All these eyes had some areas of capillary nonperfusion confirmed by fluorescein angiography and no scatter photocoagulation before the first examination. The incidence of new vessels at the optic disc (NVD) in CRVO was not significantly different from that in BRVO. However, the incidence of new vessels elsewhere (NVE) in CRVO was significantly less than that in BRVO. Follow-up vitreous examination of 36 cases while they had not developed NVD and/or NVE showed a higher incidence of posterior vitreous detachment from the mid-peripheral retina (MP-PVD) in CRVO than in BRVO. On the other hand, there was no statistically significant difference in the incidence of posterior vitreous detachment from the optic disk (D-PVD) between CRVO and BRVO. The high incidence of MP-PVD in CRVO may explain the low incidence of NVE in CRVO.

Adult↗
PubMed1997

The effect of acute experimental retinal vein occlusion on cat retinal vein pressures.

PURPOSE: Retinal ischemic damage associated with retinal vein occlusion is exacerbated by fluid extravasation and hemorrhage, which may be caused by increased permeability, elevated intravascular pressure, or both. Direct measurement of the retinal vein pressure in the cat after acute experimental retinal vein occlusion may define the role of intravascular pressures in fluid extravasation associated with this condition. METHODS: Intravenous retinal pressure measurements were obtained using a micropipette connected to a servonull device and positioned by a robot micromanipulator, while a major retinal vein near the optic disc was occluded by argon laser radiation delivered through an optical fiber positioned by a manual micromanipulator. After occlusion, retinal vein pressures were measured on both sides of the occlusion site at a controlled intraocular pressure of 20 mm Hg. RESULTS: Upstream of the occlusion site, the retinal vein pressures were not greatly elevated, although they were significantly different from controls. Downstream vein pressures were significantly lower than controls, but vascular collapse near the optic nerve was not observed. CONCLUSIONS: In retinal vein occlusion, venous pressures in a segmental retinal circulatory bed are not substantially elevated, thus implying the presence of a pressure-release mechanism and implicating vascular damage for the increased transvascular fluid flux. The lack of vascular collapse downstream of the occlusion site suggests collateral communication before a large intraocular pressure-dependent resistance segment that lies between the intraocular and extraocular vessels.

Acute Disease↗
PubMedDate not supplied

Activated protein C resistance is a risk factor for central retinal vein occlusion.

Central retinal vein occlusion is one of the most common retinal vascular disorders. Few and contrasting data are available on the prevalence of hemostatic risk factors in patients with central retinal vein occlusion. The aim of this study was to investigate the most common hemostasis-related inherited risk factors for venous thrombosis in a group of 53 central retinal vein occlusion patients (median age 59 years, range 18-77 years) and in 53 comparable control subjects (median age 57 years, range 22-84 years). No difference was found in antithrombin III, protein C and protein S plasma levels between patients and controls. At univariate analysis, activated protein C resistance (odds ratio 5.8) and factor V Leiden (odds ratio 4.4) were significantly associated with central retinal vein occlusion whereas G20210A polymorphism of the prothrombin gene was not. After adjustment for sex, age, and the other classic vascular risk factors (hypertension, diabetes, hypercholesterolemia, smoking) activated protein C resistance remained the only independent risk factor for central retinal vein occlusion (odds ratio 11.5). These data indicate that activated protein C resistance may play a role in the pathophysiology of central retinal vein occlusion.

Activated Protein C Resistance↗
PubMed1984

Characteristics of the hemispheric retinal vein occlusion.

Hemispheric retinal vein occlusions involve the venous return from approximately one-half of the retina and have characteristics of both central retinal vein occlusions and branch retinal vein occlusions. One hundred six such occlusions were studied in 104 patients whose average age was 66 years. The site of the hemispheric vein occlusion was located in a branch retinal vein in 90% of the eyes, and in 10% of the eyes it was located in one of the dual intraneural trunks of the central retinal vein. Of these eyes, 11% developed neovascularization of the disc, 9% developed neovascularization of the retina elsewhere, 9% developed neovascularization of the iris, and 3% developed neovascular glaucoma. Neovascularization was positively correlated with an increasing percentage of capillary nonperfusion (ischemic index) within the area of occlusion. Prophylactic argon laser treatment was effective in reducing the incidence of neovascularization in eyes with significant capillary nonperfusion.

Adult↗
PubMed1989

Differences in contributory factors among hemicentral, central, and branch retinal vein occlusions.

Hemicentral retinal vein occlusion (HRVO) is an anatomic variant of central retinal vein occlusion (CRVO) and thus different from branch retinal vein occlusion (BRVO). Therefore, the risk factors for HRVO should be similar to those of CRVO and different from those of BRVO. To test this, the authors compared 15 demographic and clinical variables of 28 HRVO patients with those of 117 CRVO and 214 BRVO patients. Mean age of onset and sex ratio were not significantly different among the groups. Elevated erythrocyte sedimentation rate (ESR) (P = 0.019) and elevated intraocular pressure (IOP) (P = 0.025) were significantly more prevalent in the HRVO than the BRVO group. In addition, when the authors compared CRVO with BRVO, elevated ESR (P = 0.003), elevated IOP (P = 0.015), and positive purified protein derivative (PPD) (P = 0.003) were significantly more prevalent in the CRVO than the BRVO group, whereas hypertension (P = 0.03) and hyperopia (P = 0.008) were significantly more prevalent in the BRVO group. However, of the variables tested between HRVO and CRVO patients, no significant differences were found.

Adult↗
PubMed2003

Hypercoagulable states and central retinal vein occlusion.

Central retinal vein occlusion is a common cause of permanent visual loss. Work up and laboratory evaluation of patients requires the clinician to rule out hypertension, diabetes, hyperlipidemia, and glaucoma. Patients without an identifiable risk factor are often subject to extensive testing for primary and secondary thrombophilias. The purpose this paper is to review the literature to determine which of these tests is associated with central retinal vein occlusion. Antiphospholipid antibodies and elevated plasma homocysteine levels appear to be the tests associated most commonly in patients with central retinal vein occlusion in most controlled studies. Primary thrombophilias are found rarely when screening patients with central retinal vein occlusion. Extensive testing for thrombophilias is not warranted in the vast majority of patients with central retinal vein occlusion. Older patients with any of the common vascular risk factors do not require thrombophilic screening. By carefully selecting the patients who are evaluated for thrombophilias, the likelihood of finding true-positive tests is increased.

Biomarkers↗
PubMedDate not supplied

Association of systemic diseases with retinal vein occlusive disease.

Retinal vein occlusion (RVO) is the second commonest vascular disease of the eye, second only to Diabetic Retinopathy. The association of the retinal vein occlusion with other systemic disease likes hypertension, diabetes mellitus and others has been well documented. With the increase in persons being affected from these disorders, patients with retinal vein obstruction are also increasing. Hence, a study was designed to evaluate all cases of RVO to find out its association with systemic disorders. A total of 100 patients (106 eyes) were enrolled in the study. Out of which, 66 cases reported to have Brach Retinal Vein Occlusion (BRVO) and rest 34 cases with Central Retinal Vein Occlusion (CRVO). Among the associated systemic diseases, hypertension and diabetes mellitus accounted for 84% cases. Isolated hypertension (54%) was most commonly seen followed by diabetes mellitus (8%). The prevalence of BRVO was almost twice as compared to CRVO. The high association of various systemic disorder especially Hypertension and diabetes further supports the need of early and periodic eye examination for those suffering from these disorders.

Adult↗
PubMed2003

Surgical treatments of central retinal vein occlusion.

Central retinal vein occlusion is a common retinal disease with usually severe complications. At present no safe treatment exists promoting the recovery of lost vision. Several surgical approaches to modify the natural course of the disease have been proposed in recent years. These options include laser-induced chorioretinal venous anastomosis, the injection of tissue plasminogen activator into a retinal vein, optic nerve decompression, and vitrectomy for macular edema. Even though all the proposed treatments have not yet been supported by randomized clinical trials, these techniques can be considered as innovative in an area where no effective treatment is available. Larger clinical trials are required to assess both the effectiveness and complication rate of surgical treatments designed to reverse the natural evolution of central retinal vein occlusion.

Anastomosis, Surgical↗
PubMed1990

Cases from the aerospace medicine residents' teaching file. Case #38. A navigator with nonischemic central retinal vein occlusion progressing to ischemic central retinal vein occlusion.

A case report of a young USAF navigator with nonischemic central retinal vein occlusion progressing to ischemic central retinal vein occlusion is presented. This young man was treated with hyperbaric oxygen therapy early in the course of his disease with complete resolution of his condition. Two years later his vision remained 20/17. This is the first known case of central retinal vein occlusion being treated with hyperbaric oxygen.

Adult↗