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PubMed1991

[FGF and physiopathological implications].

The role of FGF in retinal pathologies can be considered in two respects: 1-as a causative agent (for instance, stimulating aberrant growth or abnormally affecting some aspects of cellular behaviour), or 2-as a possible therapeutic drug (for instance, its ability to rescue neuronal cells from programmed or surgically-induced death), there is evidence for both: the retina, particularly the photoreceptors (PR), seems to be highly succeptible to a host of genetic defects, for instance, in the rat mutant RCS a defect in the pigmented epithelial cells (RPE) leads to the destruction of the PR. Transocular injection of FGF into RCS rats reduces the rate of PR cell loss. On the other hand, we have recently identify a difference in FGF-Receptor cell biology in the RCS mutant which may underline this particular dystrophy. Cultures of purified RPE cells were established from the dystrophic RCS rat and its congenic normal sighted control, and the number and affinity of cell surface FGF-R determined by incubation with 125I-bFGF. Scatchard analysis of the bining data indicated that whereas affinites were in both strains around 60pM, there was a large reduction in receptor number, about 70% in the mutant. Analysis of other FGF/FGF-R criteria, such as mitogenic activity, receptor molecular weight and the profile of FGF degradatoin showed no significant differences between the strains. Thus, defects in the FGF/FGF-R regulating system may actually led to retinal degeneration (RCS rat). But, once again, the underlying principles of FGF mechanisms of action in vivo are at present too incompletely understood to permit rationalization of these various observations.

Animals↗
PubMed2006

Vascular ophthalmological side effects associated with antiviral therapy for chronic hepatitis C are related to vascular endothelial growth factor levels.

We have screened for the incidence of vascular ophthalmological side effects (VOSE) in chronic hepatitis C (CHC) patients undergoing pegylated interferon (peg-IFN) plus ribavirin (RBV) therapy and sought evidence for angiogenesis activation. Thirty-four CHC patients were prospectively evaluated (18 patients with 180 microg/week of peg-IFN-alpha2a plus 800mg/day of RBV and 16 with 1.5 microg/kg/week of peg-IFN-alpha2b plus 800-1,200mg/day of RBV). Complete ophthalmological evaluation and serum vascular endothelial growth factor (VEGF) levels were assessed before and at the end of therapy. Thirteen patients (38.2%) developed VOSE, eight (23.5%) featured subconjunctival haemorrhage, and five (14.7%) had evidence of retinopathy - all were unrelated to age, sex, genotype, the type of antiviral schedule used and response to therapy. At the end of treatment, the VOSE group had significantly higher serum VEGF levels than the group of patients without detectable side effects (median 281 [range 106-386] vs 117 [83-225] pg/ml, P=0.05). These differences increased when VEGF values were corrected by platelet count. In the VOSE group, baseline VEGF and VEGF/platelet values were also significantly higher (164 [55-260] vs 64 [21-172] pg/ml, P=0.046; and 0.920 [0.217-1.543] vs 0.320 [0.100-0.661] pg/10(6) platelets, P=0.024, respectively]. In a multivariate model VEGF/platelet values at end of treatment and hepatic fibrosis stage were the only predictors of VOSE development. In 3 out of 13 patients visual acuity was affected and 2 had residual lesions in the follow-up. In this exploratory study, antiviral therapy of CHC frequently induces VOSE, apparently through an activation of angiogenesis.

Adult↗
PubMed2006

[Vitrectomy for severe proliferative diabetic retinopathy: a comparison of optical fiber free intravitreal surgery system with traditional vitrectomy].

OBJECTIVE: To compare the optical fiber free intravitreal surgery system with traditional vitrectomy in eyes with severe proliferative diabetic retinopathy (PDR). METHODS: 22 eyes of 18 patients with extensive fibrovascular proliferation associated with PDR were undergone vitrectomy using optical fiber free intravitreal surgery system (OFFISS) with bimanual technique, peeling of epiretinal membrane and/or internal limiting membrane, intraocular laser coagulation, air-fluid exchange, tamponading of air and expansive gases or silicon oil were performed according to the condition of diseases. 22 eyes with similar severity of fibrovascular proliferation treated with traditional vitrectomy were served as control. RESULTS: The operations were finished successfully in both different vitrectomy systems, but fundus cannot be visualized during fluid-gas exchange in phakic eyes, and intraocular illumination had to been used again in OFFISS group. Postoperatively, retina was fully attached in all eyes, best-corrected visual acuity of 19 eyes had improved two lines and more in OFFISS group, and 17 eyes in control group. No significant difference in surgical complications was found between OFFISS and traditional vitrectomy group. Mean duration of peeling membrane was less in OFFISS group than control group. CONCLUSIONS: The efficacy of vitrectomy using different system for severe PDR both are satisfactory and comparable. We consider vitrectomy using OFFISS more safe and effective during complicated surgical manipulations than using traditional vitrectomy system.

Adult↗
PubMed1991

[Immunohistochemical findings of epiretinal membranes after silicone oil injection].

During vitreoretinal surgery, 23 epiretinal membranes from eyes treated with silicone oil were removed. They were examined by immunohistochemical methods and compared with 15 membranes from eyes affected by proliferative vitreoretinopathy (PVR) and not treated with silicone oil and with 4 membranes from eyes with intermediate uveitis. PVR membranes from eyes treated with silicone oil showed a high level of macrophages and a strong expression of HLA-DR. Additionally, lymphocytes were found in PVR membranes, a finding that has not been described before. Similar changes were seen in proliferations removed from eyes affected by uveitis, but these membranes were found to have smaller amounts of extracellular substance. In contrast to this, most cells in the PVR membranes from eyes not treated with silicone oil react with vimentin, GFAP and cytokeratin. In none of these membranes were we able to find T-lymphocytes. It is not possible to say whether or not the different findings are attributable ot the silicone oil.

Extracellular Matrix↗
PubMedDate not supplied

[Results of experimental studies of the possibility of using low temperature in the treatment of retinopathy of prematurity].

The purpose of the paper was to study whether the use of cryotherapy can cause decrease of angiogenic activity of the primary avascular retina in kittens with oxygen induced retinopathy. The studies showed that after cryotherapy comes to a considerable decrease of angiogenic activity of this part of the retina. It indicates that cryotherapy should arrest the development of more advanced stages of retinopathy of prematurity.

Animals↗
PubMed1991

[Preventive treatment using laser of age-related macular degeneration of the contralateral eye after age-related macular degeneration of the first eye].

Since 1982, and with informed patient consent, we have photocoagulated confluent drusen and limited serous pigment epithelium detachment (SPED) in the fellow eye of ten patients suffering from advanced, disciform type, age-related macula degeneration (ARMD). This treatment was only carried out on appearance of metamorphopsia. Photocoagulation was performed with either the green ray of the argon laser, or the yellow ray of a dye laser. Spots of about 200 microns were placed in a grid-like fashion among the drusen. No complications were observed due to the treatment. The follow-up period on these ten patients, eight women and two men, mean age 77 years, was two to eight years, and the three patients have died. The drusen disappeared completely in three patients and partially in one. The functional results seemed favorable in three cases. In one case of confluent drusen associated with SPED and serous retinal detachment, vision improved remarkably from 0.3 to 0.5 with a Parinaud 2, with a follow-up of five years. In another case, the improvement was from 0.4 to 0.7 but the patient died after only a few months. In another case, vision has been stable for five years. The vision of the seven remaining patients deteriorated; three cases showed central areolar sclerosis, and one case a localised new vessel with vision less than 0.1. In three cases vision dropped to 0.2 and Parinaud 6, but they have been stable for at least four years (eight years for one patient).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

Sickle cell retinopathy.

Sickle cell retinopathy was described as early as 1930 and research has been ongoing as to the pathophysiology of the disease, its effects on the eye and successful treatment. Disease stages have been identified and treatment modalities have been established for each stage. Research results and case reports have been published in medical journals available to physicians; however, there are no identifiable publications applicable to the nursing skills required to deal with this disease. Ophthalmic nurses should be knowledgeable of the sickle cell diseases and specifically the resultant retinopathy.

Anemia, Sickle Cell↗
PubMed1991

[Thrombospondin and its importance in proliferative retinal diseases].

Thrombospondin (TSP), a platelet-derived protein of the integrin-binding family with adhesive and mitogenic properties was localized in surgically obtained epiretinal traction membranes from patients with traumatic (7/8) and idiopathic (8/8) proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR) (6/8). Using double-label immunofluorescence techniques, we demonstrated co-localization of TSP with the endothelial cell marker, von Willebrand factor, in PDR; however, only a minority of labeled macrophages showed simultaneous staining for TSP. Therefore, macrophages are probably not a major source of TSP in PVR. We demonstrated co-distribution of blood coagulation factor XIII and two of its cross-linking substrates, fibronectin and TSP, in epiretinal membranes, as well as the detection of plasmin and presumably plasmin-induced TSP breakdown products in physiologic and pathologic vitreous. These results suggest that the coagulation system has a functional role in proliferative retinal disorders and imply that the application of inhibitors of the coagulation cascade like heparin may be a potential therapeutic approach.

Antibodies, Monoclonal↗
PubMed1991

[Perfluorodecalin as a hydrokinetic substance in complicated retinal detachment].

Perfluorodecalin is a clear colourless fluid with high specific gravity. It is immiscible with gas, blood, water, or any other fluid used in vitrectomy. The low viscosity permits easy injection and removal with microsurgical equipment. The high weight displaces subretinal fluid anteriorly through retinal breaks back into the vitreous space. Posterior retinotomies can be avoided. A large bubble of perfluorodecalin in the vitreous cavity stabilizes the retina mechanically during dissection and peeling of epiretinal membranes. Before the procedure is ended the fluid must be completely removed from the eye and replaced by BSS, air, gas, or silicon oil. We present the surgical technique and preliminary results.

Fluorocarbons↗
PubMed1991

[Delayed resorption of subretinal fluid after pneumatic retinopexy].

Delayed resorption of pooled subretinal fluid has been reported to cause impaired visual acuity due to involvement of the macula in up to 10% of all case. In our series of 60 eyes treated consecutively with pneumatic retinopexy for retinal detachment, 9 eyes experienced delayed absorption of subretinal fluid. Only 6 eyes showed the phenomenon of pooled, localized subretinal fluid without peripheral extension to the ora serrata. The time for complete absorption of these circumscribed subretinal bullae ranged from 8 to 52 weeks (mean 22.7 weeks). Impaired visual acuity could not be detected in any of these cases. This may be due to the location of these bullae, which never involved the macula. Therefore, we do not consider the occurrence of this phenomenon to be a reason not to carry out pneumatic retinopexy.

Adult↗
PubMed1991

[Possibilities of silicone oil removal after complex vitreoretinal surgery].

The question of the long-term risks and benefits of silicone oil removal after complex vitreoretinal surgery involving the use of silicone oil has not yet been answered. A consecutive series of 50 eyes from which silicone oil had been removed were therefore analyzed in a retrospective study. In all cases the retina was completely attached and seemed to be stabilized before silicone oil removal. The reasons for the original surgery were severe proliferative diabetic retinopathy (PDR) in 20 cases and proliferative vitreoretinopathy (PVR) in 30, in 2 of which PVR developed after perforating injuries. Silicone oil was removed because the retina was clinically stable and completely attached, and in some cases cataract or glaucoma was present. The complication rate after silicone oil removal in these situations varied widely in dependence on the form of disease. After PDR stable conditions were achieved in 70% of cases after silicone oil removal. After PVR with retinal detachment the situation remained stable in only 50%. The most frequent complication was retinal redetachment because of recurrent PVR, accounting for 80% of all failures. The success rate with silicone oil removal after PDR in this study was independent of the duration of tamponade, which had lasted for about 1 year in most cases. Following PVR, silicone oil removal seems to be more safer after long-term tamponade (22 months) than after a shorter duration (12 months). Secondary glaucoma during silicone oil tamponade could be influenced positively in 70% of all cases by silicone oil removal. Because of the relatively high rate of complications after silicone oil removal, especially in PVR, the indications for removal must be carefully considered.

Adolescent↗
PubMed1991

[Daunomycin and silicone oil in treatment of proliferative vitreoretinopathy].

We describe the long-term results after treatment of 68 eyes in advanced stages of proliferative vitreoretinopathy with vitrectomy, daunomycin perfusion, and silicone oil injection. Six reoperations were performed. After 18 months, 73% of the eyes showed no signs of retinal detachment and 89% had a visual acuity greater than 20/800. These results are better than those reported in previously published studies. Whether this improvement is due to the daunomycin treatment or to more aggressive surgical techniques, such as retinotomies, remains to be answered by a randomized trial.

Combined Modality Therapy↗
PubMed1991

[Experimental studies of proliferative vitreoretinopathy].

A new experimental rabbit model was developed to investigate vitreoretinal proliferation (PVR). PVR was initiated by injection of zymosan A from Saccharomyces cerevisiae into the vitreous. The experiments were performed in two groups. In group A zymosan was injected into the normal vitreous; in group B zymosan was injected after the vitreous body had been degraded by the previous injection of hyaluronidase. In group A only moderate phagozytotic activity was found up to the 5 h day. However, in group B excessive invasion of macrophages was observed within 20 h and phagozytotic activity increased markedly. This was confirmed by an increase of enzymatic activity of beta-n-acetyl-glucoseaminidase in the anterior chamber and in the vitreous space. Transmission electron microscopy revealed characteristic morphology in zymosan A, which can apparently only be digested very slowly in the phagocytes. Therefore, macrophages could be traced during their transformation into fibroblastlike cells forming the vitreoretinal membranes.

Acetylglucosaminidase↗
PubMed1991

Age-related macular degeneration: current aspects of pathogenesis and treatment.

About 1.1 million people are estimated to have age-related macular degeneration in West Germany. Anatomical aspects of the normal macula and physiological ageing processes in the retina will be described including alterations in the choroid, in Bruch's membrane, the pigment epithelium and the sensory retina. Risk factors for the development of age-related macular degeneration are age per se, perhaps ethnologic characteristics, ocular characteristics, and perhaps environmental factors. The histopathology of age-related macular degeneration will be shown in respect to the formation of drusen in Bruch's membrane, changes in the retinal pigment epithelium, subretinal scar formation, and the development of subretinal choroidal neovascularisation. The clinical importance of subretinal neovascularisation will be discussed including the indications and problems of laser treatment.

Age Factors↗
PubMed1991

[Comparative immunohistochemical studies of epiretinal membranes in proliferative vitreoretinal diseases].

Epiretinal membranes are a fibrocellular tissue whose cellular components are macrophages, glial cells, retinal pigment epithelial cells and fibroblasts. In our immunohistochemical study on epiretinal membranes in proliferative vitreoretinopathy (PVR), proliferative diabetic retinopathy, macular pucker, uveitis and after intraocular silicone oil tamponade we analyzed the cellular growth patterns of these histogenetically different cell types on serial sections of paraffin-embedded and frozen material. In addition, the topographic distribution of fibronectin was analyzed and the localization of the epidermal growth factor receptor, which is the coreceptor for the transforming growth factor alpha, was examined by staining procedures. We used antibodies against macrophages (Ki-M7), cytokeratin, vimentin, desmin, glial fibrillary acidic protein and against the proliferation antigen Ki-67. The different cell systems often showed cell-type-specific growth patterns causing an "organoid" structure of the epiretinal membranes. Macrophages predominated in membranes of eyes affected by uveitis and after intraocular silicone oil tamponade. The coexistence of macrophages and other cell types within the same area might be explained by intercellular regulatory mechanisms. Fibronectin, which has functions that are important for cell adhesion, migration, proliferation and differentiation, was topographically localized mainly in areas of denser cell populations and within the walls of newly formed capillaries in diabetic membranes. There was no correlation with specific cell types, however. Among the cellular receptors necessary for signal transduction of mitogenic substances, we localized the coreceptor for the epidermal growth factor and the transforming growth factor alpha among actively proliferating macrophages in a PVR membrane.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Division↗
PubMed1990

[Pulsed Doppler ultrasonography of the ophthalmic artery in proliferating diabetic retinopathy].

In 19 patients with bilateral proliferative diabetic retinopathy we examined the blood velocity in the ophthalmic artery with pulsed ultrasound and analyzed the outline of the pulse curve with the fast fourier transformation. The data were compared with the results in 50 normal objects. Patients with diabetic proliferative retinopathy showed increased systolic blood velocities (p less than 0.05), decreased diastolic blood velocities (p less than 0.05) and an alteration in the outline of the pulse curve (p less than 0.001). These changes can be due to diabetic-induced decrease in the elasticity of the wall of the ophthalmic artery and to microangiopathic alterations in the choroid. In some patients in the course of the ophthalmic artery, we saw localized peaks in the blood velocity, which can be interpreted as local stenosis in the ophthalmic artery.

Aged↗
PubMed1990

[Acute vitreous hemorrhage--possibilities for differential diagnostic, echographic assessment].

In acute vitreal hemorrhage, echography is the method of choice for evaluation of the vitreous body. Echography ist capable of providing information on the localization, the density, and the mobility, and in certain diseases, also on the cause of the hemorrhage. The echographic findings (standardized echography) recorded in 216 patients with acute vitreal hemorrhage examined within 14 months (Jan. 1988 to Feb. 1989) were evaluated. In 91 patients (42%) diabetic retinopathy was known: in such cases echography can disclose proliferative changes and traction-detachment of the retina. In 58 patients (27%) echography revealed a posterior vitreous detachment, while in 17 patients (8%) an additional retinal detachment was found. In 39 patients (18%) a degenerative, disciform lesion of the macula was revealed as the cause of the hemorrhage, in 5 patients (2%) a malignant melanoma of the choroid, and in 2 patients a (large) retinal tear. In 5 patients, apart from the vitreous opacities no changes in the posterior segment could be found.

Diabetic Retinopathy↗