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At least 1,585 records · Page 88Linked to original sources
PubMed1995

On the nosology of the "primary true microcephaly, chorioretinal dysplasia, lymphoedema" association.

We describe a male child with prenatal growth retardation, true microcephaly, pedal lymphoedema and characteristic ocular anomalies. Ophthalmological examination revealed remnants of the posterior hyaloidea, more pronounced in the right eye where a retinal fold extended from the papilla into the vitreum, chorioretinal dysplasia with narrow retinal vessels, multiple large round areas of chorioretinal atrophy and atrophic papillae. The associations "Microcephaly-chorioretinal dysplasia", "Microcephaly-retinal folds" and "Microcephaly-lymphoedema" have been reported as separate autosomal dominant conditions. The findings in the present child suggest that these associations could be variable expressions of the same autosomal dominant condition.

Abnormalities, Multiple↗
PubMed1999

Continued lodging of retinal emboli in a patient with internal carotid artery and ophthalmic artery occlusions.

Internal carotid artery or ophthalmic artery occlusions are devastating ophthalmological events which lead to severe impairment of vision. A case of multiple branch retinal artery occlusions in a 63-year-old male with internal carotid artery and ophthalmic artery occlusions on brain angiography is presented. Emboli lodging in branches of the retinal arteries were bright, glistening, yellow or orange in appearance. Such a distinctive ophthalmoscopic appearance led to the diagnosis of cholesterol emboli. Fluorescein and indocyanine green angiography disclosed delayed filling of the retinal vessels and choroid, and showed multiple hypofluorescence distal to the vessels in which the emboli were lodged. At the time of initial examination, the number of emboli lodged in retinal arteries was estimated at more than 20. As time passed, a few of the previous emboli disappeared and new emboli appeared in other sites on fundus examination. We think that the lodging of new emboli in other sites is due to the continued break-up of atheromatous tissue through the collateral circulation associated with the occlusion of the internal carotid and ophthalmic arteries.

Acute Disease↗
PubMed2000

High frequency color Doppler image of choroidal detachment.

PURPOSE: To study the Color Doppler Image (CDI) characteristics of choroidal detachment and the applied value of CDI. METHODS: Seventy-two cases (74 eyes) of choroidal detachment were studied retrospectively. RESULTS: The typical ultragraph of chroridal detachment displayed one or several smooth hemispherical or lobuler circular thick bands, with convex side toward vitreous cavity. Most of the choroidal detachments were located before the equator, a few of them were beyond the equator. CDI displayed blood flow singnal in the band. Pulse Doppler showed the frequency spectrum features of retinal detachment band were similar to those of central retinal vessels, whereas the frequency spectum features of choroidal detachment bend resembled those of ciliary artery in some cases of retinal detachment (RD) accompanied by choroidal detachment. CONCLUSION: CDI could make a correct and precise diagnosis of choroidal detachment.

Adolescent↗
PubMed1981

Retinal branch vein occlusion.

Retinal branch vein occlusion is one of the most common diseases of the retinal vessels. In this retrospective study, 27 affected eyes were reviewed to determine the natural history, complications, and visual prognosis. Retinal branch vein occlusion most often involves temporal retinal veins at the arteriovenous crossing. The precise cause is unknown, but a high degree of association with systemic hypertension and diabetes mellitus is known. The clinical and fluorescein angiographic appearance of acute and chronic retinal branch vein occlusion is described and illustrated. The most common complications affecting visual acuity are macular edema and preretinal neovascularization. It is imperative that collateral channels be distinguished from neovascularization. If the patient's initial visual acuity is good, the prognosis is excellent, but if the initial acuity is poor, the visual outcome is less certain.

Adolescent↗
PubMed1994

[The prognosis of arterial occlusions of the eye].

Central retinal artery occlusion is caused by embolism or changes in blood rheology and viscosity. In the past, different concepts of treatment were introduced. Main princip is to improve microcirculation by increasing the pressure of perfusion, the diameter of retinal vessels or decreasing blood viscosity. Success of therapy depends on the age of artery occlusion and the rate of persisting retinal perfusion. The different concepts of therapy and their results are discussed.

Combined Modality Therapy↗
PubMedDate not supplied

Optociliary veins.

Optociliary veins occur in three clinical settings: in chronic central retinal vein obstruction, with retro-orbital tumors, and as congenital anomalies. In the last setting, associated anomalies of the disc and retinal vessels may be present, which makes differentiation from the first two difficult. Fluorescein angiography may be of value in making this differentiation for, in some if not all congenital OC veins, the direction of flow is from the choroid into the central retinal vein. Two cases are presented in which a congenital optociliary vein was present in association with a fundus picture mimicking a central retinal vein obstruction or papilledema. In both cases, fluorescein angiography demonstrated that the vessel was a congenital anomaly, draining from the choroid into the retina.

Child↗
PubMed2006

The blood pressure-induced diameter response of retinal arterioles decreases with increasing diabetic maculopathy.

BACKGROUND: The aim of the study was to compare the diameter response of retinal arterioles and retinal thickness in patients with different stages of diabetic maculopathy during an increase in the arterial blood pressure. METHODS: Four groups each consisting of 19 individuals were studied. Group A consisted of normal individuals and groups B-D consisted of type 2 diabetic patients matched for diabetes duration, age, and gender, and characterized by: Group B no retinopathy, Group C mild retinopathy, Group D maculopathy not requiring laser treatment. The diameter changes of a large retinal arteriole were measured using the Retinal Vessel Analyzer (RVA, Imedos, Germany) before, during, and after an increase in the blood pressure induced by isometric exercise. Additionally, the retinal thickness was measured using optical coherence tomography scanning. RESULTS: The arterioles contracted during isometric exercise in normal persons (diameter response: -0.70+/-0.48%) and in patients with no retinopathy (-1.15+/-0.44%), but dilated in patients with mild retinopathy (0.41+/-0.49%) and diabetic maculopathy (0.54+/-0.44%), p=0.01. Retinal thickness was normal in Group A (260+/-5.0 microm), Group B (257+/-4.5 microm), and Group C (253+/-4.4 microm), but was significantly (p=0.006) increased in Group D (279+/-5.3 microm). CONCLUSIONS: The diameter response was reduced in type 2 diabetic patients with retinopathy, whereas retinal thickness was increased in patients with diabetic maculopathy. This suggests that impairment of diameter response in retinal arterioles precedes the development of diabetic macular edema.

Arterioles↗
PubMed1987

Laminin-like immunoreactivity in induced new vessels in kitten and mouse eyes.

Laminin is a basement membrane glycoprotein, widely distributed in body tissues. It has been found on capillary basement membranes in both developing and adult retinal vessels. Oxygen-induced retinopathy was produced in kittens and mice by exposing them to a high oxygen environment during the newborn period. When the animals developed a proliferative retinopathy after a period of survival in room air, they were sacrificed and the eyes enucleated and embedded in paraffin wax. Cross-sections were cut and de-waxed. After preliminary digestion with pepsin, we used a fluorescein isothiocyanate (FITC)-labelled double antibody technique to identify laminin-like immunoreactivity (LLIR). LLIR was found on both intravitreal and intraretinal new vessels in the kitten and mouse, indicating that it is probably secreted by endothelial cells during the formation of pathological new vessels.

Animals↗
PubMed2006

[Screening analysis of retinopathy of prematurity and treatment of threshold retinopathy of prematurity].

OBJECTIVE: To investigate the incidence and the risk factors associated with the development of retinopathy of prematurity (ROP) by ROP screening in the premature infants and to evaluate the treatment effect of threshold ROP. METHODS: From March 2000 to December 2004, 108 premature infants with birth weight less than 2.0 kg or gestational age less than 37 weeks admitted to the Neonatal Intensive Care Unit at Guangdong Provincial People's Hospital were enrolled in the present study. They were examined with binocular indirect ophthalmoscope. The perinatal variables of the premature infants were analyzed to evaluate their correlation with the development of ROP. The infants with threshold ROP were treated with retinal photocoagulation or cryotherapy. RESULTS: The overall incidence of ROP was 21.3% (23 of 108). Among 23 premature infants with ROP, 56.5% (13 of 23) were in stage 1, 13.0% (3 of 23) in stage 2 and 30.4% (7 of 23) in stage 3. All infants with ROP stage 3 fulfilled the criteria of threshold ROP. As compared with non-ROP group, ROP infants had lower birth weight [(1.43 +/- 0.25) kg; t = 4.059, P < 0.001], shorter gestation age [(31.0 +/- 2.3) W; t = 2.637, P = 0.013], longer median time of oxygen supplementation (17 d; Z = -3.630, P < 0.001) and more demand of mechanical ventilation (chi(2) = 12.009, P = 0.001). Cases with multiple gestational births in ROP group were not significantly different from that in non-ROP group (chi(2) = 1.013, P = 0.314). Multivariate logistic regression analysis showed that low birth weight (beta = -2.542, OR = 0.079, P = 0.032) and mechanical ventilation (beta = 1.341, OR = 3.823, P = 0.025) were significantly associated with the development of ROP. In a total of seven cases with threshold ROP, six cases were treated with retinal laser photocoagulation or transscleral cryotherapy timely. After followed up for two months to two years, all treated eyes had normal pupil response to the light. The optic disk, macula and posterior retina appeared normal. No abnormal retinal vessels and proliferative vitreoretinopathy were found. One premature infant with threshold ROP, not treated by laser photocoagulation or transscleral cryotherapy, developed retinal detachment in both eyes. CONCLUSIONS: Premature infants with low birth weigh, shorter gestational age, longer history of oxygen supplemental and the using of mechanical ventilation have more chance of developing ROP. The analysis of risk factors will be helpful in understanding and prediction of development of ROP. ROP screening and timely treatment for threshold ROP are very important for preventing the development of advanced ROP in premature infants.

Female↗
PubMed1990

[Microscopic quantification of fluorescein distribution in retinas of normal and diabetic rats].

To identify more precisely the site and the nature of the abnormality of the Blood-Retinal Barrier (B.R.B.) in diabetes, quantitative fluorescence microscopy was used to measure time-dependent changes of fluorescence in ocular tissues of normal and diabetic rats, after intravenous fluorescein injection. Fluorescein distribution across the retinal layers was studied in control and streptozotocin diabetic rats at 5, 30 and 60 minutes after dye injection. Fluorescein intensities of choriocapillaris and retina were compared with plasma fluorescein levels. The results show a B.R.B. dysfunction in diabetic rats arising from abnormal leakage of fluorescein into the retina. After 60 minutes there was a greater fluorescence intensity localized to the inner retinal layers, consistent with a probable inhibition or saturation of active transport mechanisms for dye removal through the retinal vessels.

Animals↗
PubMed2003

Fluorescein and indocyanine green angiography findings in Behçet's disease.

AIM: To evaluate and compare the fluorescein (FA) and indocyanine green angiographic (ICGA) findings, and to investigate the choroidal involvement in Behçet's disease. METHODS: FA and ICGA were performed on 112 eyes of 62 patients with Behçet's disease, between November 1993 and July 2002, using Topcon IMAGEnet Digital System. Patients were aged 16-50 years; 48 (77.4%) were male and 14 (22.6%) were female. RESULTS: FA showed dye leakage from retinal vessels in 57 (50.9%) eyes, cystoid macular oedema in 18 eyes (16.1%), optic disc oedema in four eyes (3.6%), disc neovascularisation in three eyes (2.7%), and retinal neovascularisation in two eyes (1.8%). ICGA showed hyperfluorescent lesions in 40 eyes (35.7%), hypofluorescent lesions in 17 eyes (15.2%), hyperfluorescent and hypofluorescent lesions in 12 (10.7%) eyes, ICG leakage from choroidal vessels in 11 eyes (9.8%), irregular filling of choriocapillaris in five eyes (4.5%), and choroidal filling defect in four eyes (3.6%). Hyperfluorescent and hypofluorescent lesions which were seen in 53 out of 69 eyes (76.8%) on ICGA, were not visible on FA. 55 eyes (49.1%) showed hyperfluorescence on the disc on both FA and ICGA, whereas 36 (32.1%) showed hyperfluorescence only on FA. CONCLUSION: The hyperfluorescence and/or hypofluorescence, irregular filling of the choriocapillaris, choroidal filling defect, and ICG leakage from choroidal vessels seen only on ICGA may suggest choroidal involvement in Behçet's disease.

Adolescent↗
PubMed2003

Reproducibility and clinical application of a newly developed stabilized retinal laser Doppler instrument.

PURPOSE: To describe a newly developed stabilized retinal laser Doppler instrument, to report the reproducibility of retinal blood flow measurements, and to present examples of its clinical application. DESIGN: Experimental study. METHODS: The intrasession, intersession, and interobserver reproducibility of retinal blood flow measurements obtained using the Canon Laser Blood Flowmeter model CLBF 100 was assessed. Intrasession: the coefficients of variation (CV) for repeated measurements (5X) of retinal vessel diameter (D), time-average centerline blood velocity (V(av)), and blood flow (F) were calculated at 18 sites along temporal retinal arteries and 18 sites along temporal retinal veins using both eyes in six healthy volunteers. Intersession: the correlation coefficients and average differences between two sets of measurements at the same 36 retinal sites made by one examiner on two different days were calculated. Interobserver: the correlation coefficients and average differences between two sets of measurements at nine sites (five arterial and four venous) in five eyes of five of the volunteers made by two examiners on the same day were calculated. Results from two patients, one with branch retinal vein occlusion (BRVO), and one with central retinal vein occlusion (CRVO), are used to illustrate abnormal retinal circulatory characteristics. RESULTS: intrasession: CV (mean +/- SD) for D, V(av), and F were 5.5% +/- 2.2%, 13.1% +/- 6.3%, and 13.8% +/- 4.7% in arteries and 3.5% +/- 2.1%, 11.9% +/- 5.9%, and 12.7% +/- 5.5% in veins. Intersession/interobserver: strong correlations between measurements made by one examiner on two different days and by two examiners on the same day were found in D, V(av), and F. Average differences in F were 16.4% +/- 12.8% for intersession and 12.6% +/- 7.0% for interobserver comparisons. Results from the patient with BRVO show marked differences in flow characteristics in the affected quadrant compared with an unaffected quadrant in the same eye, and to the fellow eye. Results from the patient with CRVO show a dramatic improvement in flow characteristics after clearing of the occlusion. CONCLUSIONS: The reproducibility results and the fact that blood flow is measured in actual units of microl/min indicate that the instrument can be used for reliable comparison of blood flow characteristics at different retinal vascular sites in the same eye, at comparable sites in both eyes, and for comparison between patients and healthy control subjects.

Adult↗
PubMed1991

Vitreous fluorophotometric recordings in HIV infection.

Fluorophotometry was performed in 10 patients. Five of these were affected by AIDS and five ARC (AIDS Related Complex). All patients had normal fundi detectable by standard examination and by fluorescein angiography. In spite of the normal condition of the fundus, vitreous fluorophotometry readings were constantly above normal. We believe that the disturbance of the blood retinal barrier appears before any lesion detectable both clinically and by fluorangiography. It is possible that the first toxic effect of the retrovirus is at the level of the retinal vessels.

AIDS-Related Complex↗
PubMed2001

Hydranencephaly in an infant with vascular malformations.

Hydranencephaly is a condition in which cerebral hemispheres are absent and reduced to fluid-filled sacs in a normal skull. Numerous causes have been proposed. We report a male infant with hydranencephaly and congenital vascular malformations (port wine stains, generalized nevus flammeus, anomalous retinal vessels, and absent internal carotid flow). Magnetic resonance imaging of the brain showed absence of most of the cerebrum except for small portions of the occipital cortex and thalami. Magnetic resonance angiography showed flow within the vertebral and basilar arteries without internal carotid intracranial flow above the internal carotid petrous and cavernous portion. This is a report of cutaneous and retinal malformations associated with hydranencephaly. Vascular malformations of larger vessels (e.g., webbing of the carotid arteries and an absent internal carotid arterial system) have been observed in other infants with hydranencephaly, and are proposed to lead to brain destruction. The case reported herein supports the role of primary vascular malformations in the development of some cases of hydranencephaly.

Blood Vessels↗
PubMed1981

Experimental allergic encephalomyelitis. II. Retinal and other ocular manifestations.

Experimental allergic encephalomyelitis (EAE) was produced in 6 adult rhesus monkeys. All the animals developed acute EAE. Optic neuritis developed in all eyes. A vasculo-occlusive retinopathy was seen in five of the 12 eyes. Conjunctivitis and iridocyclitis were seen in some eyes. The available evidence indicates that the retinopathy is secondary to the optic nerve changes and represents central retinal vein occlusion by intraneural compression. Histopathologic studies revealed no evidence of inflammatory infiltration in the retina or around the retinal vessels.

Animals↗
PubMed1993

Asymmetric distribution of arteriovenous crossings in the normal retina.

BACKGROUND: Recently, there has been renewed interest in the orientation of the crossing retinal vessels at arteriovenous intersections, particularly as it relates to the risk of branch vein occlusion. Little is known about the distribution of the two types of crossings in the normal retina. METHODS: The authors studied standard fundus photographs of 51 subjects without retinal disease. Arteriovenous crossings were analyzed for fundus location and relative orientation of the crossing vessels (vein-posterior or vein-anterior). FINDINGS: In the superotemporal quadrant, crossings were distributed closer to the optic disc (P < 0.001), and a greater proportion of crossings were vein-posterior (P = 0.01) than in the inferotemporal quadrant. As a result, within a 3-disc diameter (DD) radius of the optic disc, there were significantly more vein-posterior crossings in the superotemporal than in the inferotemporal quadrant (P < 0.001). CONCLUSION: These findings further define normal retinal vascular anatomy and may explain the predilection for branch retinal vein occlusions to occur in the superotemporal quadrant.

Adult↗
PubMed1992

Local production of fibronectin by ectopic human retinal cells.

The distribution of fibronectin mRNA and fibronectin in adult human retina and epiretinal membranes was investigated by in situ hybridisation and immunohistochemical techniques. The cells in normal adult retina contained little or no fibronectin mRNA and the retina only showed fibronectin immunoreactivity in retinal vessels. The cells in detached neuroretina did not contain fibronectin message but the vitreoretinal interface of the detached retina exhibited variable fibronectin immunoreactivity. Retinal glia, retinal pigment epithelium and fibroblast-like cells in membranes at the vitreoretinal juncture (epiretinal membranes) showed variable labelling with the fibronectin mRNA probe and all the membranes immunostained for fibronectin. No difference could be detected between membrane cell types in the intensity of labelling with the mRNA probe or for fibronectin immunoreactivity. The results indicate that cells in situ in attached and detached adult human retina do not produce fibronectin. Although fibronectin at the vitreoretinal juncture in retinal detachment is probably partly derived from plasma fibronectin resulting from breakdown of the blood-retinal barrier, ectopic retinal cells produce fibronectin and contribute to the glycoprotein epiretinal membranes.

Adolescent↗
PubMed1978

Retinal damage produced by intraocular fiber optic light.

We exposed the maculas of owl monkey eyes to light from an intraocular fiber optic light source similar to that used for human pars plana vitrectomy. Retinal irradiance was calculated at 0.22 W/cm2. Eyes were exposed for time intervals ranging from 30 minutes to five minutes and were observed after light treatment by fundus photography and fluorescein angiography. Tissue was obtained for light and electron microscopy by animal killing at one hour, 24 hours, one week, and four weeks. Fundus lesions were seen ophthalmoscopically as early as five hours following 30 minutes of light exposure. Significant damage to the photoreceptor layer and less damage to the pigment epithelium was present by light and electron microscopy as early as one hour after 30 minutes of light exposure. By one month complete loss of photoreceptors with Müller cell junctions between inner retina and flattened abnormal retinal pigment epithelium cells was observed. Fluorescein angiography revealed significant staining of the pigment epithelium and outer retina 24 hours after 30 minutes of light exposure. No leakage from retinal vessels occurred. At one month following light treatment, transmission of choroidal fluorescein through window defects in the pigment epithelium was present with no retinal staining. The threshold for ophthalmoscopically visible fundus lesions in this study was 15 minutes of light exposure. Ten minutes of light treatment was the threshold for microscopic changes. Short light exposures damaged the outer retina and spared the pigment epithelium. Removing a substantial amount of the infrared light from our light source did not protect the retina from damage. Removal of light between 400 and 500 nm is probably more helpful in protecting the retina. Intermittent light exposure of the retina seemed as harmful as uninterrupted illumination for the same cumulative period of time. We speculate that the retinal damage caused by intraocular fiber optic light has primarily a photic mechanism. Damage to the retinal pigment epithelium may be secondary to outer retinal damage. The present levels of intraocular light used for human pars plana vitrectomy are probably safe in most instances. Lengthy preretinal membrane stripping procedures during vitrectomy, however, may pose a threat of light damage to the retina. This damage must be appreciated as continued efforts are made to produce brighter sources of intraocular light for human pars plana vitrectomy.

Animals↗