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Purpose: To describe a case of ocular decompression syndrome in a patient after trabeculectomy with mitomycin C for neovascular glaucoma., Results: Diffuse retinal hemorrhages developed in the posterior pole of a patient with neovascular glaucoma after he underwent trabeculectomy with mitomycin C. The hemorrhages persisted for less than 9 months., Conclusions: Acute decompression of the eye in patients with high intraocular pressure can lead to the development of posterior pole hemorrhages. The course of this rare syndrome is relatively benign.

Vitreous surgery with retinal vein cannulation and injection of tissue plasminogen activator was performed in 8 eyes of 8 patients with longstanding visual loss secondary to central retinal vein occlusion. A modest improvement in visual acuity was demonstrated in 4 of the 8 eyes, and 3 of the 8 eyes maintained the preoperative vision. Retinal vein cannulation may offer a new treatment option for patients with central retinal vein occlusion.

The paper reviews the actual therapeutical means in a severe invalid eye disease. The treatment is not able to improve the retinal blood flow, being more effective on the main symptoms and complications. The isovolumetric hemodilution method as an up-to-date method in the treatment of central retinal vein occlusion, appears to bring better recuperation hopes, by a higher improvement of the local anatomical and hemodynamical factors. That is the reason why we shall expose it widely in our paper. Unfortunately, despite its complexity, the treatment of central retinal vein occlusion is not satisfactory from the point of view of the high number of patients that remain with a low visual acuity. The main goal of the therapy is the recovery of visual function, but a few aspects and especially the late presentation for ophthalmological examination, reduce the objective of treatment to prevent complications.

Promoting the formation of new collateral vessels in ischemic tissues using angiogenic growth factors (therapeutic angiogenesis) is a an exciting frontier of cardiovascular medicine. Conversely, inhibition of the action of key regulators of angiogenesis, such as VEGF, constitutes a promising approach for the treatment of solid tumors and intraocular neovascular syndromes. These concepts are being tested now in clinical trials.

Purpose: The development of extended territories of nonperfused capillaries after branch vein occlusion (b.v.o.) is correlated to the secondary constriction of the arteriole crossing the occluded territory. Local NO release is impaired soon after b.v.o. and accounts for the secondary arteriolar constriction. In this report we present evidences showing that administration of an NO donor can reverse the secondary arteriolar vasoconstriction observed after b.v.o., Material and Methods: Simultaneous preretinal NO profiles and arteriolar diameter measurements were performed in miniature pigs after experimental b.v.o. The effect of preretinal microinjections of the NO-donor Sodium Nitroprusside on the arteriolar diameter was studied., Results: A significant arteriolar vasoconstriction occurring in parallel with a preretinal [NO] decrease was observed 4 hours after b.v.o. Microinjection of the NO-donor SNP caused a segmental, reversible arteriolar dilatation., Conclusion: The present results, suggest that local NO supply in the first hours following b.v.o. may contribute to protect the retina against ischemic injury.

Purpose: To report a case of bilateral panuveitis associated with diffuse infiltrative lymphocytosis syndrome (DILS)., Methods: Case report. A 35-year-old woman with known human immunodeficiency virus (HIV) infection developed bilateral uveitis with retinal periphlebitis in association with diffuse infiltrative lymphocytosis syndrome., Results: Detailed comprehensive examination and investigations were performed and recognized causes of panuveitis excluded., Conclusion: To the best of our knowledge, we report the first case of retinal findings associated with diffuse infiltrative lymphocytosis syndrome.

Purpose: To report the injection of tissue plasminogen activator into a retinal vein to treat central retinal vein occlusion., Methods: An 81-year-old woman with visual loss of the right eye secondary to central retinal vein occlusion developed central retinal vein occlusion and visual loss in her left eye. Treatment of her left eye with topical ocular hypotensive medications, pentoxifylline, and laser chorioretinal anastomosis was without benefit. Thereafter, she underwent vitreoretinal surgery, including tissue plasminogen activator injection into a branch retinal vein of her left eye., Results: The patient reported subjective improvement in the vision of her left eye. Ophthalmoscopic and fluorescein angiographic improvement were also noted., Conclusion: The feasibility of cannulating a retinal vein for treatment has been demonstrated.

Purpose: To determine the short- and long-term effects of betaxolol and timolol on human retinal circulation., Methods: In a double-masked, randomised, placebo-controlled study we evaluated the effects of both a one-drop application and a twice-daily 2-week application of either topical 0.5% betaxolol hydrochloride or topical 0.5% timolol maleate on the retinal circulation in 12 healthy volunteers. Laser Doppler velocimetry was used to detect changes in the retinal venous blood flow., Results: In both betaxolol- and timolol-treated eyes, intraocular pressure decreased significantly compared with baseline values after both 90 min and 2 weeks. In betaxolol-treated eyes, retinal blood flow did not change significantly after 90 min, but increased significantly (14 +/- 9%; p = 0.02) compared with baseline after 2 weeks. In timolol-treated eyes, retinal blood flow decreased significantly (18 +/- 5%: p = 0.04) compared with baseline after 90 min, and also decreased significantly (14 +/- 6%; p = 0.04) compared with baseline after 2 weeks., Conclusions: Retinal blood flow increases as a long-term effect of betaxolol and decreases as both a short- and long-term effects of timolol.

Background: Fluorescein angiography with a scanning laser ophthalmoscope allows the quantification of morphologic and dynamic changes in the retina. In two patients with central retinal vein occlusion we monitored the progression of the cystoid macular edema (CME) and changes of microcirculation with a follow up of 4 to 6 months., Materials and Methods: Two patients with central retinal vein occlusion and CME were examined by means of digital fluorescein angiography. Arteriovenous passage times and macular capillary blood velocities in combination with quantifications of the macular angioarchitecture and the extent of the CME were evaluated., Results: Hemodilution therapy improved retinal circulation, whereas macular circulation and the severity of the CME remained unchanged. With persisting CME oral acetazolamid therapy was initiated. Oral Acetazolamide led to resorption of the cystoid edema in tandem with improved macular circulation. The capillary density was altered but remained unchanged over time., Conclusions: By means of digital analysis of fluorescein angiograms a detailed monitoring and retinal and macular dynamics, macular morphology is possible. In these two cases CME improved after Acetazolamide and moreover retinal circulation returned to normal conditions.

Purpose: This is the first report of the monitoring of the clinical progress of a central retinal vein occlusion by measuring the retinal venous collapse pressure using ophthalmodynamometry., Method: A 38-year-old woman with a nonischaemic central retinal vein occlusion received systemic prednisone. The dose of prednisone was increased and decreased both abruptly and gradually. The response was monitored by weekly measurements of visual acuity, retinal appearance and retinal venous collapse pressure. The retinal appearance was assessed by comparison of repeated stereo colour photographs and fluorescein angiographs. Retinal venous collapse pressure was estimated by taking the mean of four or more ophthalmodynamometric measurements., Results: An inverse relationship between the ophthalmodynamometric retinal venous collapse pressure and systemic prednisone dosage was observed. The visual acuity and retinal appearance remained unchanged throughout the follow-up., Conclusions: Ophthalmodynamometry in this case was a useful method of quantitatively monitoring the response of central retinal vein occlusion to systemic prednisone. The response would not have been detected if only visual acuity and retinal appearance were used to monitor the progress.

In 18 patients with retinal vein occlusion the authors used Pentoxifylline in droplet infusion for an increased deformation of erythrocytes. In all the patients they observed a substantial improvement of all physiological parameters of the visual system.

Recent studies have found basic fibroblast growth factor (bFGF), an angiogenic peptide, in retina and have suggested that bFGF is responsible for retinal vascular proliferation. To test the hypothesis that bFGF stimulates 3H-thymidine uptake in retinal vascular cells in vivo, we injected bFGF (100 ng) into the vitreous cavity of six cats at 0 hr and again at 24 hr. Eight control eyes received boiled bFGF or no injection. After 46 hr, 3H-thymidine was injected into the vitreous cavity of all eyes and 2 hr later the eyes were enucleated. Intense 3H-thymidine uptake was seen in eyes with bFGF (56 +/- 20 SD positive cells per section) but not in control eyes (7-10 positive cells per section (P less than 0.001). Trypsin digest preparations showed that the thymidine uptake was predominantly in the venular (89%) and capillary (10%) endothelium and not in arterioles (1%) (P less than 0.001). The data suggest that retinal venular endothelial cells respond preferentially to exogenous bFGF, and in part may explain their prominent role in the neovascular process. In a second group of experiments to test the hypothesis that retinal ischemia releases a diffusable factor similar to bFGF that can cause 3H-thymidine uptake in retinal vascular cells, we created branch retinal vein occlusion in six cat eyes. The fellow eyes received no injections. In the eyes with branch vein occlusion there was an intense 3H-thymidine uptake within the distribution of the occluded vein (84 +/- 77 SD positive cells per section), but none in the areas outside the occluded vein (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

We studied the effect of topical timolol maleate 0.5% on the retinal circulation of eyes with ocular hypertension using laser Doppler velocimetry and monochromatic fundus photography. Patients with ocular hypertension had normal eye examinations and had documented elevated intraocular pressures of 23 mmHg or higher on two or more separate occasions. In a double-masked randomized design, one eye of each subject received timolol maleate 0.5% and the fellow eye received placebo. Vessel diameter, maximum velocity of red blood cells, and volumetric blood flow rate were determined in a major retinal vein of each eye just prior to the instillation of drops, and then 2 hr later. In comparison to the baseline value, there was an increase of 12.0% in average red blood cell velocity (P less than 0.005, statistically significant) and of 8.4% in volumetric blood flow rate in the timolol-treated eyes (P less than 0.05, statistically significant). No significant changes in these quantities were observed in the placebo-treated eyes. Also, no significant change in venous diameter was detected in the placebo- and the timolol-treated eyes. In comparison to the baseline, a significantly larger increase in red blood cell velocity was observed in the timolol-treated eyes than in the placebo-treated eyes (P less than 0.05). The difference between the increase in blood flow observed in the timolol-treated eyes and the placebo-treated eyes achieved a probability value of P = 0.058. The increase in blood flow observed in the timolol-treated eyes may be related to the increase in perfusion pressure produced by this drug.

Timolol is widely used in glaucoma treatment without sufficient knowledge of its vascular retinal effects. In this study, we measured the retinal vessel diameters before and after instillation of 0.5% timolol twice daily in one eye for 1 week, using photographic enlargements (x44). A total of 12 normal, caucasian subjects aged 25-39 years (average, 30.6 +/- 4.2 years) participated in this study. In all, 75% of the subjects had a diminution of retinal arterial size in the treated eye. The mean arterial diametric decrease was 4.1% in treated eyes compared with both untreated eyes and pretreatment values of treated eyes. These diminutions were statistically significant according to Student's paired t-test (P less than 0.05). No statistical difference was found in venous diameters (t = -0.065). Results showed that 0.5% timolol may have a vasoconstrictive effect on the retinal arteries of normal human subjects after 1 week of unilateral instillation twice daily. We suggest that this arterial vasoconstriction could be caused by the effect of timolol on the vascular beta-2 receptors. Further investigations are warranted to determine whether timolol also acts on ciliary arteries and whether arterial vasoconstriction participates in lowering intraocular pressure.

In 48 cases with well-documented retinal vasculopathy, the therapeutic effect of cinnarizine and flunarizine over a period of several months to 3 years has been clinically evaluated. Objective measurements comprised determination of visual field and acuity, funduscopy, three-mirror funduscopy, and fluorangiography with determination of capillary leakage and circulation time. The most prominent features were disappearance of cotton wool nodules, improvement of visual function and capillary perfusion, inhibition of capillary leakage, and a positive hemokinetic effect in arteriolar, capillary, and venous beds. Degeneration of post-ganglionic fibers was partly restored. In some patients with glaucoma, the aspect of the optic disc was normalized. It is concluded that selective calcium-entry-blockers clearly improve tissue perfusion in ischemic areas.

Animals were given a 0.1-mL intravitreous injection of various agents and followed up with frequent ophthalmoscopic examinations. Fundus photographs were performed before injection and at six and 24 hours after injection. Vascular caliber was assessed by a previously described technique of performing measurements on fundus photographs taken and projected in a standardized fashion. No significant vascular dilation was identified for vehicle alone, carbachol, histamine, isoproterenol hydrochloride, or bradykinin. Mild dilation within one hour, but not persisting for 24 hours, was noted for dibutyryl cyclic adenosine monophosphate. Prominent dilation within one hour, becoming maximal by five hours but not persisting for 24 hours, was noted for adenosine, dipyridamole, and sodium nitroprusside. The adenosine-induced vasodilation was effectively blocked by an adenosine receptor antagonist, BW-A1433U. N-ethylcarboxamidoadenosine (NECA), a nonspecific adenosine selective agonist, was a much more potent vasodilator than two relatively selective A1 adenosine agonists, N6-cyclopentyladenosine and N6-phenylisopropyladenosine, suggesting that A2 receptors are involved. The vascular dilation caused by adenosine, dipyridamole, and particularly NECA, but not nitroprusside or dibutyryl cyclic adenosine monophosphate, was accompanied by retinal hemorrhages, producing a picture reminiscent of some features of ischemic retinopathies. This study suggests that adenosine may be an important mediator of vasodilation, and therefore blood flow, in the retina.

One dose of each prostaglandin preparation was injected into the vitreous body of the right eye of 64 rabbits. Doses less than 200mug caused no toxicity. Doses greater than 200mug exhibited the following changes observed by ophthalmoscopic observation, fluorescein angiography, histologic preparation, and electron microscopy: vascular leakage, vascular occlusion, hemorrhage, and retinal detachment. Electron micrographs revealed damaged retinal vascular endothelial cells. These changes were considered secondary toxic phenomena and did not occur at physiologic prostaglandin concentrations.

A 40-year-old woman took oral contraceptives for four years. She developed a vascular glaucoma and one year later the eye was enucleated. No other apparent cause for the occlusion was present. The vascular occlusion consisted of a combined central retinal artery and vein occlusion with severe intimal hyperplasia. An intravascular granulomatous reaction is attributed to chronic vascular injury.