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So-called "central retinal vein occlusion". I. Pathogenesis, terminology, clinical features.

Pathogenesis of occlusion of the central retinal vessels, based on experimental and clinical findings, is discussed. It suggests that the so-called "central retinal vein occlusion" represents not only occlusion of the central retinal vein but also retinal arterial ischemia. Based on this pathogenesis the following terminology is recommended for central retinal vascular occlusion: (a) Ischemic retinopathy is due to occlusion of the central retinal artery. (b) Venous stasis retinopathy is due to occlusion of the central retinal vein alone. (c) Hemorrhagic retinopathy is due to occlusion of the central retinal vein associated with retinal ischemia. Clinical findings of (b) and (c) are compared which indicate that the two conditions are distinct entities and unfortunately so far have been dumped under a common heading of so-called "central retinal vein occlusions". Such a distinction is extremely important before any attempts are made to evaluate their natural history or effects of any therapy on them.

Humans↗

Retinal vasculitis in rheumatoid arthritis: an angiographic study.

The authors studied sixty patients affected by classical or definite rheumatoid arthritis (RA), to evaluate the possible existence of retinal vasculitis, by employing fluorescein angiography. Retinal vasculitis was found in 18% of the examined patients, even if no clinical and ophthalmoscopic signs of retinal vessel inflammation were present. The authors suggest that the retina should be examined in RA patients, since retinal vasculitis may be asymptomatic at the beginning, but can represent one of the possible extra-articular manifestations of the disease.

Adult↗

[Ocular signs of primary hyperoxaluria type I].

PURPOSE: To report the results of ophthalmological examination of 14 patients with primary oxalosis of type I, and to appreciate the diagnostic value of these signs. MATERIAL AND METHODS: Fourteen patients, 7 girls and 7 boys with an average age of 8-35 years (3 months - 15 years). Ten patients had renal failure, 2 died without dialysis and eight were treated with dialysis; 5 out of 8 had hemodialysis and the duration of this treatment varied between 3 months and 3.5 years, 3 out of 8 had peritoneal dialysis. RESULTS: Visual acuity was 10/10 in 11 cases and we noted a vision of 5/10 in one eye in one case. Ocular fundus examination was normal in 7 cases. In 5 cases, it showed numerous minute white round flecks at the posterior pole and near the retinal vessels which probably correspond to deposition of calcium oxalate crystals. In one case we found a diffuse retinal pigment atrophy and in another case a sectorial papillar atrophy without loss of vision. CONCLUSION: This flecked retinopathy can occur before hemodialysis or after a few months or years of hemodialysis. There is no correlation between duration of dialysis and ocular lesions.

Adolescent↗

Angiogenic factors in human proliferative sickle cell retinopathy.

BACKGROUND/AIMS: Preretinal neovascular formations called sea fans develop at the border of non-perfused peripheral retina in sickle cell retinopathy. Angiogenic factors which could contribute to their development, however, have not been examined previously. The objective of this study was to determine immunohistochemically if vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) were associated with sea fan formations. METHODS: Immunohistochemistry on cryosections was used to localise bFGF, VEGF, heparan sulphate proteoglycan, human serum albumin, collagens IV and II, and von Willebrand factor in tissue from five sickle cell and one control subject. RESULTS: The greatest immunoreactivity for VEGF and bFGF was in the feeder and preretinal vessels of sea fans (p<0.01). The most prominent reaction product was localised to vascular endothelial cells. In retinal vessels, VEGF and bFGF immunoreactivities were greater in sickle cell subjects (both proliferative and non-proliferative) than in the control subject (p<0.01 and p<0.02 respectively). In the sickle cell retina, no angiogenic factor immunoreactivity was detected in non-perfused periphery and there was no significant difference in bFGF or VEGF immunoreactivity between perfused retina and the border of perfused and non-perfused areas. CONCLUSION: Our results demonstrate for the first time that VEGF and bFGF are associated with sea fan formations in sickle cell retinopathy. Both factors may function in an autocrine manner because immunoreactivity for these factors was greater within the neovascularisation than in adjacent retina.

Adolescent↗

Ultrastructural and immunocytochemical studies of iris vessels in rats with experimental autoimmune uveoretinitis.

In this study, we describe the ultrastructural and immunocytochemical changes that occur in the iris of rats with experimental autoimmune uveoretinitis (EAU). General changes include perivascular infiltration of inflammatory cells, followed by hemorrhage and extensive tissue destruction. Alterations in the iris epithelium were also noted. A breakdown in the blood-iris barrier was demonstrated in some vessels at the peak of inflammation; peroxidase reaction product was seen in the basement membrane and perivascular spaces. We found that, in inflamed iris vessels, endothelial cells and smooth muscle cells become hypertrophic and show increased amounts of synthetic organelles. This finding is similar to our previous observations on endothelial cells and smooth muscle cells in retinal vessels in EAU. In addition, as was reported in the retinal vascular basement membrane in EAU, there is an increase in immunoreactivity of several extracellular matrix molecules in the iris vascular basement membrane; during inflammation, there is a significant increase in immunoreactivity of collagen types I and III, entactin, fibronectin, and laminin. Activated endothelial cells and smooth muscle cells are likely to be involved in the synthesis of certain of these matrix molecules.

Animals↗

Early biosynthetic changes in the diabetic-like retinopathy of galactose-fed rats.

The histological lesions of diabetic micro-angiopathy have a long latency, but vascular cell function may be affected at early stages of the process. Rats with experimental galactosaemia develop a diabetic-like retinopathy in the absence of other metabolic abnormalities characteristic of diabetes mellitus; basement membrane thickening is measurable in their retinal vessels after 7 months of galactose feeding. To examine the course of biosynthetic changes relevant to the process, retinal expression of collagen IV and fibronectin were compared in rats fed a 30% galactose diet or a control diet for 5 or 9 weeks. Total retinal RNA was studied by reverse transcription-polymerase chain reaction; the fibronectin primers encompassed the alternatively spliced EIIIA exon. The levels of alpha 1 (IV) collagen and fibronectin mRNAs were measured relative to an internal standard (beta-actin mRNA). The proportion of EIIIA+ to EIIIA- fibronectin transcripts was similar in the retinas of control and galactose-fed rats, which, however, showed increased levels of both fibronectin and collagen IV mRNAs in the presence of unchanged beta-actin mRNA levels. An upward trend was detected by 5 weeks of galactose feeding; and after 9 weeks the fibronectin/actin ratio was 1.2 +/- 0.3 vs 0.8 +/- 0.2 in controls (p = 0.015) and the collagen IV/actin ratio was 1.3 +/- 0.3 vs 0.9 +/- 0.2 in controls (p = 0.04). Thus, hyperhexosaemia of a few weeks' duration is a perturbation sufficient to increase the synthesis of basement membrane components in the retina. The search for additional early biosynthetic changes should assist in reconstructing the pathogenesis of hexose-induced retinal microangiopathy.

Actins↗

Retinal blood flow measurements in branch retinal vein occlusion using scanning laser Doppler flowmetry.

PURPOSE: To determine capillary blood flow measurements in eyes with branch retinal vein occlusion using a scanning laser Doppler flowmeter. METHODS: Retinal capillary blood flow in branch retinal vein occlusion areas and corresponding ipsilateral nonbranch retinal vein occlusion areas, 11 equivalent areas of the contralateral fellow eye of 12 consecutive untreated branch retinal vein occlusion patients, and 16 eyes of 11 age-matched normal control subjects were measured with scanning laser Doppler flowmetry. A template consisting of eight squares, each with a field of 100 x 100 microm (10 x 10 pixel) with space interval of 500 microm equidistant horizontally and vertically was used to obtain blood flow measurements in all subjects. Mean blood volume, flow, and velocity were obtained by averaging the mean values measured in each field. We avoided measurement over large retinal vessels to prevent the aliasing artifact of blood cells from moving faster than the sampling frequency. RESULTS: Branch retinal vein occlusion areas have significantly decreased microvascular blood volume (P = .0009), flow (P = .02), and velocity (P = .016) compared with ipsilateral nonbranch retinal vein occlusion areas in the same eye. Branch retinal vein occlusion areas also have decreased blood volume (P = .001), flow (P = .0042), and velocity (P = .0044) compared with areas of contralateral fellow eyes of branch retinal vein occlusion subjects. Branch retinal vein occlusion areas have significantly decreased blood volume (P = .0012), flow (P = .008), and velocity (P = .02) compared with age-matched normal areas. CONCLUSION: Average retinal blood volume, flow, and velocity in areas of branch retinal vein occlusion are significantly lower than in healthy retinas. The ability to noninvasively measure hemodynamic changes in the retinal capillary bed may be relevant to development of new therapies for retinovascular disease.

Aged↗

Idiopathic juxtafoveolar retinal telangiectasia: a review and case report.

Idiopathic juxtafoveolar retinal telangiectasis is a group of retinal vascular anomalies characterized by retinal vessel dilation and tortuosity, multiple aneurysm formations, varying degrees of vascular leakage and lipid exudate deposition. Idiopathic juxtafoveolar retinal telangiectasis may occur as a primary disorder (either congenital or acquired), or may be caused or accompanied by other systemic or ocular diseases. The visual prognosis and effectiveness of therapy is dependent upon the etiology of the retinal telangiectasis. Included in this review is a case report, as well as the classification system used to identify idiopathic juxtafoveolar retinal telangiectasia.

Journal Article↗

Immunolocalization of transforming growth factor-alpha and its receptor in the normal and hyperoxia-exposed neonatal rat retina.

PURPOSE: Transforming growth factor-alpha (TGF-alpha) is a mitogenic polypeptide for a variety of different cells types including retinal neurons and glial cells. We have examined the temporal and spatial expression of TGF-alpha and its receptor in the normal and hyperoxia-exposed neonatal rat retina to determine if the expression is consistent with a role in retinal development and response to retinal injury. METHODS: We have used immunohistochemistry to examine TGF-alpha and epidermal growth factor receptor (EGF-R) on postnatal days (1, 5, 10, 14, 18, and 25). To examine TGF-alpha and EGF-R expression after retinal injury we studied the retinas from rats which were exposed to 80% oxygen for 10 days and then recovered in room air. Immunolocalization of type IV collagen was performed to examine the retinal vasculature development after hyperoxia. RESULTS: The pattern of TGF-alpha and EGF-R expression in the neural retina evolved from a diffuse pattern on postnatal day 1 to restricted sites on postnatal day 14. The TGF-alpha immunoreactivity was consistent with localization in Müller cells on postnatal day 14. Both TGF-alpha and EGF-R patterns were altered in the retinas from rats that had been exposed to hyperoxia and recovered in room air for 4 days. The type IV confirmed immunostaining confirmed vaso-obliteration in the deep layer of retinal vessels after hyperoxia. CONCLUSIONS: Our findings of altered expression of TGF-alpha and EGF-R during retinal development suggests a biological function for this growth factor, possibly promoting retinal cell proliferation, differentiation, and survival. The altered immunolocalization of TGF-alpha and EGF-R in the hyperoxia-exposed retina suggest that TGF-alpha is likely involved in the retinal response to injury.

Animals↗

Fluorescein angiography in the long-term follow-up of choroidal melanoma after conservative treatment.

Three patients showed a growing choroidal melanoma, of them 2 in the only eye. The tumours were treated with Ru106/Rh106 plaques and surrounded by argon or krypton photocoagulation. The patients were followed up for 34-36 months by regular fluorescein angiography. In areas in which the radiation effect was optimal most choroidal and retinal vessels disappeared within 3-6 months. Outside this area occlusion of the vasculature as well as progressing atrophy of the tumour and the overlying retinal pigment epithelium were seen to continue for more than 12 months after treatment. Disappearance of the leaking vessels of the tumour may be the most reliable fluorescein angiographic sign of tumour regression following conservative treatment.

Aged↗

Retinal contraction and metamorphopsia scores in eyes with idiopathic epiretinal membrane.

PURPOSE: Using M-CHARTS (Inami Co., Tokyo, Japan), which were developed by the authors to measure metamorphopsia, and image-analysis software, which was developed to quantify retinal contraction, the authors investigated the relationship between the degree of retinal contraction and the degree of metamorphopsia in eyes with idiopathic epiretinal membrane (ERM). METHODS: This study was conducted in 29 eyes with ERM (29 patients, 20 women; mean age, 62.1 +/- 8.6 years) observed for at least 3 years (mean, 3.55 +/- 0.6 years) after diagnosis. Horizontal (MH) and vertical (MV) metamorphopsia scores were obtained with the M-CHARTS. Horizontal and vertical retinal contraction due to ERM was measured by using image-analysis software developed by the authors to calculate horizontal and vertical components of changes in the locations of retinal vessels on sequential fundus images. RESULTS: There was a significant (P < 0.01) positive correlation between the degree of retinal contraction and metamorphopsia score. In addition, there were significant positive correlations between horizontal contraction of the retina and the MV score (P < 0.01) and between vertical contraction of the retina and the MH score (P < 0.05). No significant correlations were found between change in the metamorphopsia score and change in visual acuity or mean defect. CONCLUSIONS: Metamorphopsia scores correlate well with measurements of retinal contraction due to idiopathic ERM. Using M-CHARTS is a simple and useful method for quantitatively monitoring metamorphopsia in patients with ERM.

Contracture↗

Myogenic response reduction by high blood glucose levels in human retinal arterioles.

PURPOSE: The effect of elevated blood glucose level on the myogenic response of human retinal arterioles to acute increases in blood pressure is investigated. METHODS: The vascular response to raised blood pressure (Bayliss effect) was measured in 12 healthy volunteers by use of the retinal vessel analyzer (RVA). For a 9-minute period an on-line measurement of the diameter of a retinal branch arteriole was performed. After the first 3 minutes (baseline measurement) a second phase with 3 minutes of isometric exercise caused an acute rise in blood pressure, followed by 3 minutes of recovery (phase III). After the first session 100 g glucose were administered per os. After 30 minutes blood glucose was measured again and an identical second session was performed with higher blood glucose levels. The Wilcoxon test was used for statistical analysis. RESULTS: During the first session a rise in mean arterial pressure of 22.8 (+/-8.4) mmHg was followed by an arterial vasoconstriction of -6.6 (+/-1.7) %. The administration of 100 g glucose resulted in a significant rise in blood glucose levels within 30 minutes between the two sessions (4.35 mmol/L vs 7.46 mmol/L) (p=0.002). The blood pressure rise of 25.7 (+/-7.3) mm Hg in the second session was associated with a significant loss in arterial vasoconstriction of -2.3 (+/-1.4) % (session I vs session II p=0.002). CONCLUSIONS: The myogenic response of the arterial wall in human retinal arterioles was significantly reduced during acute rise of blood glucose levels.

Adult↗

Fluorescein fundus angiography of stroke-prone SHR.

The fluorescein fundus angiography was performed on SHRSP, SHR, and NR. The following results were obtained. 1. No expravasation of fluorescein from retinal vessels of SHR and NR was observed at any phase of circulation. 2. The extravasation of fluorescein from retinal arterioles and peripapillary capillary of SHRSP of post-hypertensive stage was seen at arterial phase of circulation. These extravasation of fluorescein coincided with the initial stage of stroke incidence.

Animals↗

Ocular findings in 55 patients with Down's syndrome.

Fifty-five patients with Down's syndrome were examined to evaluate the characteristics and frequency of ocular findings. Of these patients, 29 (52.7%) were hypermetropes, 7 (12.7%) were emmetropes, and 7 (12.7%) were myopes; astigmatism of more than 3.00 diopters was present in 7(12.7%) patients. Strabismus was observed in 12 (21.8%) patients. All but one of these 12 patients also had esotropia. Congenital nasolacrimal duct obstruction was present in 12 subjects (21.8%). Blepharitis was found in 19 (34.5%) cases. Nystagmus occurred in 7 (12.7%) patients. Brushfield spots were detected in only 20 (36.3%) of the patients and were more common in light-colored irides. Lens opacities were diagnosed in 11 (20%) patients, and two underwent successful cataract surgery. On fundus examination, an increased number of retinal vessels crossing the optic nerve head was detected in 21 (38.1%) cases. One of the patients had a retinal detachment. Significant but correctable ocular problems are present in patients with Down's syndrome and may interfere with the quality of life of the patient and with binocular vision. Surgical intervention may be needed for strabismus and for cataracts.

Adolescent↗

[Pulsating macroaneurysm of a retinal arterial branch].

Pulsating macroaneurysms of retinal vessels have so far been described only as isolated cases. The case reported here was a 72-year-old female patient with systemic hypertension and suspected Raynaud's disease. The pulsating macroaneurysm was only observed for a few days; subsequently it fibrosed and an arterial branch occlusion was demonstrated. Retinal macroaneurysms have been mentioned in combination with aneurysmal cerebral vessels in hypertonic patients, suggesting generalized vessel wall disease. This patient's central visual acuity was hardly affected, even after a number of months, and photocoagulation treatment was thus unnecessary. Such treatment for retinal macroaneurysms should be considered in each case individually, depending on the extent of bleeding and edema.

Aged↗

Local fibrinolytic activity of human optic nerve vessels.

The local fibrinolytic activity of the human optic nerve vessels was investigated in 25 eyes obtained at autopsy using Todd's fibrinolysis autography. The veins generally showed higher fibrinolytic activity than the arteries except for the central retinal vessels, as was the case in the systemic blood vessels. Out of 25 cases, 6 (24%) showed a lower activity in the central retinal veins than in the arteries, 7 (28%) a higher activity in the veins than in the arteries and in 12 (48%) the tendency was transitional.

Adult↗

[Fundus fluorescein and indocyanine green angiographic study of Behcet's disease and Vogt-Koyanagi-Harada syndrome].

OBJECTIVE: To study the choroidal and retinal changes in Behcet's disease and Vogt-Koyanagi-Harada syndrome (VKHS) using indocyanine green angiography (ICGA) and fundus fluorescein angiography (FFA). METHODS: Seventeen cases (27 eyes) of Behcet's disease and 18 cases (36 eyes) of VKHS were examined with FFA and ICGA. All of the patients showed an active intraocular inflammation when examined. RESULTS: FFA showed leakage from retinal vessels in patients with Behcet's disease. ICGA revealed choroidal abnormalities including dilatation and hyperpermeability of choroidal vessels in 11 eyes (40.7%). In VKHS, FFA revealed the hyperfluorescence and serous pigment epithelium detachments. Dilatation and hyperpermeability of choroidal vessels revealed by ICGA were found in 36 eyes (100%), multihypofluorescent dark dots in 32 eyes (88.9%), and choroidal filling defects in 28 eyes (77.8%). CONCLUSIONS: Although retinal vascular lesions are predominant in Behcet's disease, choroidal abnormalities evidenced by dilatation of choroidal vessels are also present in some patients. Hyperfluorescence and hypofluorescence revealed are the main findings in the patients with VKHS. A combination of FFA and ICGA is recommended for the examination of Behcet's disease and VKHS.

Adult↗

Acute annular outer retinopathy as a variant of acute zonal occult outer retinopathy.

PURPOSE: A 23-year-old man developed a rapid-onset, large, dense scotoma that was associated with a peculiar gray intraretinal ring corresponding to the edge of the scotoma and normal fluorescein angiographic findings. This disorder may represent a variant of acute zonal occult outer retinopathy. METHODS: We studied one patient by ophthalmoscopic examination and fluorescein angiography. RESULTS: The patient experienced a short period of concentric enlargement of the scotoma and narrowing of the retinal vessels within the ring, followed by stabilization of the scotoma and slow progressive depigmentation and intraretinal migration of the retinal pigment epithelium within the zone of visual loss. The cause of this disorder, which affects primarily the outer retina, was not determined. CONCLUSIONS: We speculate that this disorder is part of the spectrum of acute zonal occult outer retinopathy and that the gray border, which separates the normal from the abnormal retina, represents an immune ring phenomenon.

Acute Disease↗