Retinal Venous Occlusive Disease Research Articles

SCOREing in Retinal Venous Occlusive Disease

SCOREing in Retinal Venous Occlusive Disease

Artery, Vein, Neither, Both?

Combined central retinal vein and central retinal artery occlusion is a rare complication of compressive or infiltrative optic nerve disease. In this case combined retinal arterial and venous occlusive disease was the presenting sign of metastatic adenocarcinoma to the optic nerve sheath. An optic nerve sheath biopsy led to the diagnosis. Clinicians should be aware that retinal vascular disease can be due to optic nerve disorders including metastatic carcinoma.

Increased plasma asymmetric dimethylarginine (ADMA) levels in retinal venous occlusive disease

We investigated the levels of the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA), as well as homocysteine and cysteine thiols, in a cohort of subjects affected by retinal vein occlusion (RVO) disease. Capillary electrophoresis analysis was performed in both RVO subjects (n=54) and in a control group (n=32). No differences were found between controls and patients; however, after categorisation for RVO type, central RVO (CRVO) patients showed higher levels of ADMA (0.710+/-0.139 micromol/L) than controls (0.635+/-0.117 micromol/L) and branch RVO patients (0.642+/-0.096 micromol/L). Moreover, cysteine plasma levels were also significantly higher in CRVO patients than in controls (265.8+/-46.9 vs. 226.7+/-51.9 micromol/L, p<0.01), while homocysteine plasma concentration was more or less identical in all groups. We hypothesise that the elevated levels of cysteine in CRVO patients may post-translationally inhibit dimethylarginine dimethylaminohydrolase enzyme activity, as already described for homocysteine, thus contributing to the accumulation of ADMA in this patient group.

Plasma methionine determination by capillary electrophoresis–UV assay: Application on patients affected by retinal venous occlusive disease

Methionine is an important amino acid involved in protein synthesis and transmethylation reactions. It is also the precursor of homocysteine and cysteine, two important risk factors for cardiovascular diseases. As homocysteine research has gained impulsion, the evaluation of plasma methionine concentrations has acquired importance. Methionine measurement generally has been performed by HPLC after o-phthalaldehyde derivatization. Its separation from other amino acids is time-consuming. We set up a new specific capillary electrophoresis method in which analyte derivatization was avoided by sample concentration before analysis. Methionine was detected by UV absorbance at 204 nm with a detection limit of 0.5 μmol/L. By a capillary with an effective length of 50 cm filled with 125 mmol/L Tris phosphate buffer at pH 2.3, the separation occurred in less than 14 min. Precision tests indicated a good test repeatability for both migration times (coefficient of variation [CV] < 0.3%) and areas (CV < 2.0%). Moreover, a good reproducibility of intraassay and interassay tests was obtained (CV < 2.9% and CV < 3.5%, respectively). The Passing–Bablok regression and the Bland–Altman test for methods comparison suggest that the data obtained by our method and by a reference HPLC assay are similar. Assay performance was evaluated measuring methionine concentrations in retinal venous occlusive disease.

Potential future treatment strategies for retinal vein occlusion

Our understanding of the pathophysiology of retinal venous occlusive disease is limited and the number of proven therapies is even more so. As a result, there is a growing number of unproven treatment strategies. The majority of these unproven treatments attempt to reduce the macular edema, which is a consequence of the vein occlusion, but few attempt to improve the underlying retinal venous outflow, retinal perfusion and oxygenation. A more thorough knowledge of the natural history is needed to better determine any actual therapeutic benefit of these current treatments. A greater knowledge of the molecular and hemodynamic pathophysiology is also required to allow the development of future treatment strategies. In this article, pharmacological and surgical treatment strategies are reviewed, as well as selected ongoing clinical trials for retinal venous occlusions.

The Antiphospholipid Antibody Syndrome Research in Patients with Retinal Venous Occlusion

The antiphospholipid antibody syndrome (APAS) is a condition associated with abnormal thrombosis and the presence of anticardiolipin antibodies (aCL). Thirty-two patients (20 male and 12 female) aged between 29 and 75 years (mean +/- SD: 56.4 +/- 12.34) with retinal venous occlusive disease were studied. All patients with a history of venous occlusive disease within the previous 8 months were included in the study. Diagnoses were made by fundus examination and fundus fluorescein angiography (FFA). Anticardiolipin IgM and IgG antibodies, antinuclear antibodies (ANA), and IL-1beta were investigated in all patients. Neither aCL-IgM nor aCL-IgG was observed as positive in this group. Only four patients were found to be ANA positive. However, serum levels of IL-1beta were higher than those of controls (p <0.001). Mean IL-1beta was found to be 18.06 +/- 3.39 pg/mL (mean +/- SE), respectively. IL-1beta levels were found to be significantly different from those of controls (2.7 +/- 0.68 pg/mL) (p <0.001). In this study, antiphospholipid antibody positivity was not determined in any patients. As a result, IL-1beta level appears higher in retinal venous occlusive disease. This cytokine measurement might be used as a diagnostic indicator for venous occlusive disease.

Controversy in the Management of Retinal Venous Occlusive Disease

Controversy in the Management of Retinal Venous Occlusive Disease

Retinal and optic nerve diseases.

A variety of disease processes can affect the retina and/or the optic nerve, including vascular or ischemic disease, inflammatory or infectious disease, and degenerative disease. These disease processes may selectively damage certain parts of the retina or optic nerve, and the specific areas that are damaged may have implications for the design of potential therapeutic visual prosthetic devices. Outer retinal diseases include age-related macular degeneration, pathologic myopia, and retinitis pigmentosa. Although the retinal photoreceptors may be lost, the inner retina is relatively well-preserved in these diseases and may be a target for retinal prosthetic devices. Inner retinal diseases include retinal vascular diseases such as diabetic retinopathy, retinal venous occlusive disease, and retinopathy of prematurity. Other retinal diseases such as ocular infections (retinitis, endophthalmitis) may affect all retinal layers. Because the inner retinal cells, including the retinal ganglion cells, may be destroyed in these diseases (inner retinal or whole retinal), prosthetic devices that stimulate the inner retina may not be effective. Common optic nerve diseases include glaucoma, optic neuritis, and ischemic optic neuropathy. Because the ganglion cell nerve fibers themselves are damaged, visual prosthetics for these diseases will need to target more distal portions of the visual pathway, such as the visual cortex. Clearly, a sound understanding of retinal and optic nerve disease pathophysiology is critical for designing and choosing the optimal visual prosthetic device.

Anticardiolipin antibodies in patients with retinal vein occlusion and no risk factors: a prospective study.

Several reports have described the association between antiphospholipid antibodies (APAs) and retinal venous occlusive (RVO) disease. The purpose of this study was to look at the prevalence of these antibodies in patients with RVO disease and no conventional risk factors. We specifically examined how APAs may affect the course of this disease. Twenty-four patients with the diagnosis of RVO disease were screened prospectively for APAs. All were free from risk factors for retinal vein thrombosis and other immunologic conditions. Patients were observed for a period of 3 to 12 months. Lupus anticoagulant was negative in all 24 patients. Ten (43%) of 24 patients had anticardiolipin antibodies (ACAs). All patients with ACAs were younger than 45 years of age, with an average age of 33 years. The average age of patients with no ACAs was 66 years. Comparison of the average age of the two groups showed a statistically significant difference. There was no statistical significance between the two groups for development of neovascular disease. Seropositive patients who developed neovascularization had elevated titers for an average of 11.8 weeks versus 3.3 weeks for those who did not have neovascularization. Neovascular complications generally began several weeks after the titers became negative. There was a significant prevalence of ACAs in young patients with RVO disease and no associated systemic risk factors. Seropositive patients who developed neovascular disease had elevated titers for more than 6 weeks. However, the role of these transient ACAs in retinal vein occlusion is still not clear and merits further study.

Homocysteine: a risk factor for retinal venous occlusive disease 1,2

Purpose Recent studies have shown a relationship between elevated levels of homocysteine and vascular disease including cerebrovascular accidents and myocardial infarctions. We evaluated patients with a recent retinal vein occlusion to determine if there was an associated elevation of homocysteine. Design Age and gender matched case-controlled study. Participants Twenty patients with retinal venous occlusive disease within the previous 6-month period and 40 control patients without retinal venous occlusive disease were enrolled in the study. Methods Twenty patients with a history of retinal vein occlusion underwent laboratory testing to determine serum homocysteine levels. In addition, a health survey was completed and several laboratory tests relating to vascular disease including cholesterol were checked. Two control groups were selected. The first group included patients with diabetes and no history of retinal vascular occlusive disease. The second control group included nondiabetic patients who also had no prior history of retinal vascular occlusive disease. Main outcome measures The main parameter measured in this study is fasting homocysteine. Results Fifteen of 20 patients (75%) with retinal vein occlusion disease had an elevated fasting serum homocysteine level, whereas only 5 of 40 control patients (13%) had an abnormal homocysteine level ( P < 0.0005). Conclusions Patients with retinal venous occlusive disease have higher levels of homocysteine, which may serve as a modifiable risk factor.

Structural Changes of the Retina in Retinal Vein Occlusion-Imaging and Quantification With Optical Coherence Tomography

To evaluate the potential of optical coherence tomography (OCT) for imaging and quantifying structural changes in the retinal architecture following venous occlusive disease. We studied 20 patients with retinal venous occlusive disease: 5 patients suffered from branch retinal vein occlusion (BRVO), and 15 from central retinal vein occlusion (CRVO). Patients with CRVO were studied within 72 hours after the first onset of symptoms. Patients were examined by OCT after a complete ophthalmologic examination including fluorescein angiography. A standard set of linear scans through the center of fixation and individual scans over areas of special interest were performed. Scans were qualitatively evaluated and quantitative measurements were performed on single A-scans at 5 locations of linear scans. Measurements were taken in the center of fixation, at the foveal rim, and at the edge of the scan. We measured total retinal thickness, thickness of cystoid spaces, and thickness of the highly reflective outer band. OCT produced detailed images of retinal thickening, intra- and subretinal hemorrhage, intra- and subretinal fluid accumulation, and formation of intraretinal cystoid spaces. Quantitative evaluation revealed a mean central retinal thickness of 274 +/- 181 microm (72-760 microm) in patients with central retinal vein occlusion. Visual acuity did not correlate with central or extrafoveal retinal thickness. Optical coherence tomography is a useful imaging technique for studying changes of retinal architecture following venous occlusive disease. Even minor changes like localized subretinal fluid accumulation or beginning epiretinal membrane formation can be visualized in detail. In contrast to other diseases like diabetic maculopathy, quantitative assessment of macular thickness does not correlate to visual acuity. Nevertheless, because of detailed imaging, OCT might become a useful tool in the follow-up and treatment of individual patients.

Retinal Venous Occlusive Disease

Retinal Venous Occlusive Disease

Visual Symptoms Associated with the Presence of a Lupus Anticoagulant

The lupus anticoagulant is an acquired serum immunoglobulin that prolongs several coagulation parameters, most notably the partial thromboplastin time (PTT), Most commonly, this condition is found in association with systemic lupus erythematosus (SLE) but may be seen with other collagen-vascular diseases and in otherwise healthy individuals. Despite the laboratory tests suggesting impaired coagulation, clinically the lupus anticoagulant has been associated with thrombosis. The authors present five patients with the lupus anticoagulant who came to medical attention because of branch retinal artery occlusion, ischemic optic neuropathy, transient visual loss, transient diplopia, or vertebrobasilar insufficiency. Eleven previously reported patients with the lupus anticoagulant and disturbed vision are also reviewed with additional findings of retinal venous occlusive disease and homonymous visual field loss. The relationship of these findings to retinopathy in SLE is discussed. Patients with the lupus anticoagulant (with or without SLE) may develop disturbances in vision due to thrombosis from a hypercoagulable state. We recommended obtaining a PTT, VDRL, and the more sensitive anticardiolipin antibody in patients with unexplained visual symptoms.

Clinical application of the laser Doppler technique for retinal blood flow studies.

The newly developed laser Doppler technique was used to measure retinal blood flow characteristics in patients with forms of central retinal venous occlusive disease. The measurements were consistent with the expected reduced retinal blood flow in these disease processes.

Retinal neovascularization after retinal vaso-obliteration. Frequency--origin--morphology.

Retinal neovascularization (NV) was found microscopically in 76% of 74 eyes with neovascular glaucoma after retinal vaso-obliteration, and in 75% or more of eyes with any type of retinal vascular occlusive disease. Preretinal NV was encountered in 47% and prepapillary NV in 49%. Retinal arterial occlusive disease was more often an underlying condition (81%) than retinal venous occlusive disease (49%). Morphological stages of retinal NV in adults are (1) insudation and/or transudation of vessel walls (100%) with endothelial proliferation (97%) and (2) capillary formation (76%). The latter takes place via intramural capillaries (31%) and endothelial plexuses (24%), and from pre-existent capillaries. New capillaries arise from arterioles, venules and capillaries. Hyalinization can be found in any retinal vessel type. Retinal NV is primarily induced by retinal hypoxia.

The Natural Course of Central Retinal Vein Occlusion

Thirty-five patients with central retinal vein occlusion had an extensive medical and laboratory evaluation to identify possible etiologic factors. We describe the natural course of the two forms of retinal venous occlusive disease, hemorrhagic retinopathy and venous stasis retinopathy, by observing a group of 25 untreated patients from one to eight years. Systemic vascular disease was most commonly associated with retinal venous occlusive disease. The visual prognosis is favorable in venous stasis retinopathy and extremely poor in hemorrhagic retinopathy. However, two of ten patients with venous stasis retinopathy developed hemorrhagic retinopathy with poor visual outcome.

Photocoagulation in Venous Occlusive Disease

Fifty-one eyes with branch or tributary retinal venous occlusive disease underwent photocoagulation (1970-1973) after certain criteria were met: reduced visual acutity, fluorescein angiographic documentation of vessel permeability changes, and either dye leakage into the macula or neovascularization of the retina, or both. Eighty-four percent of the eyes responded to treatment with an improvement or stabilization in visual acuity, a reduction in collateral vessel caliber and permeability, and reduced dye accumlation in the macular area and increased fluorescein transit time. Photocoagulation is an affective means of reducing macular edema resulting from vascular compensatory changes following venous occlusion and decreases the risk of vitreous hemorrhage from sites of retinal neovascularization.