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At least 1,333 records · Page 74Linked to original sources
PubMed2005

Bilateral peripapillary subretinal neovessel membrane associated with chronic papilledema: report of two cases.

BACKGROUND: Increased intracranial pressure (ICP) usually results in headaches and papilledema with infrequent loss of visual acuity. Peripapillary subretinal neovessel membranes (PSNVM) rarely complicate chronic papilledema. HISTORY AND SIGNS: Case 1: A headache-free 9-year-old boy presented with a bilateral loss of vision due to chronic papilledema. Bilateral PSNVM was present. Cerebral imaging revealed a pilocytic astrocytoma and hydrocephaly. Case 2: A headache-free 39-year-old man presented with severe visual loss of the left eye due to an exudative macular star. Severe papilledema and PSNVM were present in both eyes due to idiopathic intracranial hypertension. THERAPY AND OUTCOME: Lowering of ICP (tumor resection - Case 1 and lumboperitoneal shunt - Case 2) resulted in involution of the PSNVMs in both patients. No improvement of visual acuity occurred for Case 1 (optic atrophy) but Case 2 benefited from gradual visual recovery. CONCLUSIONS: PSNVMs are rare complications of chronic papilledema, as only 10 patients have been reported so far in the literature. Absence of headaches in both of our patients was probably responsible for the late diagnosis, hence chronicity of papilledema. Laser therapy of PSNVM might not be necessary once the ICP is lowered.

Adult↗
PubMed2005

Pericytes and the pathogenesis of diabetic retinopathy.

Incipient diabetic retinopathy is characterized by increased vascular permeability and progressive vascular occlusion. Pericyte loss precedes capillary occlusion in the diabetic retina, but its cause remains unclear. One concept proposes that pericyte loss is the result of toxic product accumulation and induction of destructive cellular signals generated within the pericyte. Alternatively, new experimental data indicate that pericyte dropout may result from regulations which induce pericyte elimination as an active process. Pericytes are critical for the development of a proper retinal network, and appear protective for endothelial cells under hyperglycemic conditions. The unifying hypothesis of hyperglycemia-induced microvascular damage centers around hyperglycemia-induced mitochondrial overproduction of reactive oxygen species. The pharmacological prevention of acellular capillaries without the rescue of pericyte loss in experimental diabetic retinopathy suggests that the endothelium is the primary therapeutic target.

Animals↗
PubMed2006

Macular atrophy after combined intravitreal triamcinolone acetonide (IVTA) and photodynamic therapy (PDT) for retinal angiomatous proliferation (RAP).

BACKGROUND: Retinal angiomatous proliferation (RAP) is a variant of exudative AMD that appears to respond poorly to standard PDT. This pilot study explores the potential efficacy and safety of combined intravitreal triamcinolone acetonide (IVTA). PATIENTS AND METHODS: In a prospective interventional case series 10 eyes of 8 patients with RAP were treated with combined IVTA/PDT. RESULTS: After 3 months there was no evidence of significant exudative activity in 7/10 eyes treated with IVTA/PDT, three eyes required re-treatment. After 6 months 4/10 eyes were "dry" on fluorescein angiography, visual acuity was stable (loss of less than 3 Snellen lines) or had improved in 5/10 eyes. 5/10 eyes had lost 3 or more lines, due to central macular atrophy in 4/5 eyes and secondary to a progressive exudative lesion in 1/5 eyes. CONCLUSIONS: Intravitreal steroids combined with PDT appear to be a step ahead in the treatment of RAP. Our results, however, raise the question whether combined treatment may create more atrophy leading to vision loss in some cases.

Aged↗
PubMed1997

[Cryocoagulation in therapy of proliferative diabetic retinopathy].

BACKGROUND: The importance and indication of panretinal photocoagulation in proliferative diabetic retinopathy is well established. In contrast the indication of cryotherapy in this disease is more controversial especially in regard of new indications for early vitrectomy. The present study was performed to characterize the clinical possibilities and limitations of cryotherapy in complicated proliferative diabetic retinopathy. PATIENTS AND METHODS: In 231 patients with proliferative diabetic retinopathy and vitreous hemorrhage limiting further photocoagulation the visual outcome and diabetic retinal changes were observed before and after cyrotherapy (15-20 effects) of the ophthalmoscopically visible peripheral retina. RESULTS: After cryotherapy regression of active proliferations could be seen in 70% of the patients. Resorption of vitreous hemorrhages could be found in 80% of the patients. This was associated with improvement in visual acuity in 50-60% of the patients. Loss of vision was caused due to tractional detachment in 20% of the patients and due to further vitreous hemorrhages in 10% of the patients. Comparison of retinal changes between patients with worsened visual acuity and patients with increase in visual acuity demonstrated the preoperative fibrotic status of disc neovascularisation as the most important prognostic factor. The development of central tractional detachment was significantly higher in patients with preoperatively partly regressed disc neovascularisation. CONCLUSIONS: Cryotherapy of the peripheral retina in proliferative diabetic retinopathy with vitreous hemorrhages is therefore only indicated after ophthalmoscopical or echographical exclusion of peripapillary fibrosis and retinal traction and with sufficient visibility of the peripheral retina for the application.

Adult↗
PubMed1996

[Fluorescence angiography in age-related macular degeneration. Study of the incidence of lesions treatable with coagulation].

BACKGROUND: The treatment of late age-related Macular Degeneration (AMD) according to the results of prospective clinical studies is indicated in classical choroidal neovascularisations (NV), which can be delineated from the center of the fovea. To evaluate the effectiveness of this therapy, the knowledge of the frequency of treatable lesions in the spectrum of late AMD is important. PATIENTS AND METHODS: The frequency of different manifestations of late AMD and of lesions treatable with photocoagulation according to the results of prospective clinical studies was recorded in a consecutive series of 2503 fluorescein angiogramms in patients with symptomatic late AMD. RESULTS: Classical choroidal NV could be detected in 35.4% of the patients. In 5.5% of the patients these NV were extra- or juxtafoveolar and therefore laser treatment could be recommended. 10.2% of the patients demonstrated small (< 1 PD) subfoveal classical NV and 20.4% of the patients showed large (> 1 PD) subfoveal NV or membranes associated with large subfoveal, subretinal hemorrhages. Occult choroidal NV could be seen in 41.8% of the patients. These occult NV were larger 1 PD in 21.9% of the patients and small (< 1 PD) in 19.9% of the patients. Pigment epithial detachments (PED) could be seen in 14.6% of the patients (9.9 vascular PED, 3.7% avascular PED, 1.0% rip of the retinal pigment epithelium). Disciform scars were present in 7.2% of the angiogramms. CONCLUSIONS: The spectrum of late AMD can be differentiated in several clinical features. In this consecutive series of 2503 symptomatic AMD patients only appr. 6%% of the patients could be treated with laser treatment according to the results of prospective clinical studies. Because in addition the success of this treatment is very limited, the development of new therapeutic options is one of the major tasks in ophthalmology.

Aged↗
PubMed1995

[Laser coagulation of senile, moist macular degeneration].

Age-related macular degeneration (AMD) is a common disease in ophthalmology. The current status of knowledge in subretinal neovascularisations concerning epidemiology and treatment based on the findings of the macular photocoagulation study is shown. Most important parameters in treatment of subretinal neovascularisations in AMD are exact localization of the membrane in fluorescein angiography, its size and the visual acuity. The treatment of extra-foveal, well demarcated membranes can be recommended. Moreover recent results in the treatment of subfoveal, well demarcated membranes show some benefit for the patient as long as the size of the membrane is lower than 2 discs areas and the actual visual acuity is taken into account. Indocyanin-Green-(ICG)-angiography is recommended in occult subretinal membranes. Guidelines for the treatment are given.

Aged↗
PubMed1994

[Postoperative leakage of silicone oil into the anterior chamber].

BACKGROUND: One reason for complications after silicone oil application is the postoperative entrance of silicone oil into the anterior chamber. In a retrospective study, we tried to define risk factors for oil entrance into the anterior chamber. METHODS: 159 Eyes of 148 patients, vitrectomized and filled with silicone oil between 1988 and 1992 were analysed. In 22 eyes (13.8%) silicone oil entered the anterior chamber postoperatively. Eyes with emulsified oil in the anterior chamber and eyes, where the oil entered the anterior chamber during cataract extraction were not included in this group. Diagnoses, postoperative fundus findings and lens status, intraocular pressure, depth of the anterior chamber and time of the oil entrance were analysed. RESULTS: Risk factors in the first 10 postoperative days (14 eyes = 63.6%) seem to be aphakia and choroidal effusions, especially if combined with buckling procedures (encircling bands). In the late postoperative period, i.e. up to 6.5 months (8 eyes = 36.4%), proliferative vitreoretinopathy was responsible for the entrance of silicone oil into the anterior chamber in all cases. The decreased production of aqueous humour combined with hypotony seems also to play an important role in this process. CONCLUSIONS: It seems that in the early postoperative period the frequency of oil entrance into the anterior chamber can only be lowered by a subtotal oil filling in aphakic eyes with accompanying encircling procedures. It remains open if radical amputation of the vitreous base can avoid peripheral reproliferations.

Anterior Chamber↗
PubMed1993

[Indications for photocoagulation in diabetic retinopathy].

Since the publication of randomized studies essentially performed in England and the United States, indications to photocoagulation in most cases of diabetic retinopathy have become precise and accepted by all physicians who take care of diabetics. These indications are reviewed following these randomized studies and the programme of blindness prevention recommended by the World Health Organization and the International Diabetes Federation. Presentation of the techniques used in Lausanne.

Diabetic Retinopathy↗
PubMed1993

[Growth inhibition of intraocular proliferative explants under in vitro conditions by verapamil].

BACKGROUND: For the treatment of non neoplastic proliferations in the fundus, a nontoxic, proliferation-inhibiting long-term therapy would be desirable in addition to vitreoretinal surgery. In theory, the use of calcium channel blockers as a means of prevention appears promising. METHODS: In order to test the action of Verapamil in the above application, 42 preretinal, epiretinal and subretinal membranes were removed during pars plana vitrectomy between May, 1991 and June, 1992. Following crushing, these were cultured under cell culture conditions. RESULTS: Cell division outside the membranes was seen in 27 cases. In 13 cases the minimum cell count was approximately 1000 per primary culture. Subcultures were prepared from each of the latter, the cells having been divided into four portions. Two of the samples were diluted with Verapamil in a concentration of 0.25 microgram/ml. When cell fusion began, the number of intact cells in each sample was determined. Verapamil inhibited growth significantly (significance level of 0.93, P < 0.01). CONCLUSIONS: A larger number of cases would have to be studied to permit more comprehensive conclusions.

Adolescent↗
PubMed1993

[Role of the vitreous body in diabetic retinopathy].

UNLABELLED: In recent years it has become evident that the vitreous must play a role in various aspects of diabetic retinopathy. The exact role of the vitreous is however in many aspects still ill defined. There are structural changes of the vitreous, as for instance vitreous liquefaction and posterior vitreous detachment, that are associated with the occurrence and earlier onset of diabetic retinopathy. Further there are angiogenic and angioinhibitory factors in the vitreous which influence neovascularisation by means of endothelial cell proliferation. Photocoagulation of the retina can cause structural changes (posterior vitreal detachment) and histological changes (increased hyalocytes activity) which can protect against the progression of proliferative diabetic retinopathy. The role of vitrectomy in protecting against proliferative diabetic retinopathy is generally concerned to be related to the removal of the vitreal scaffold. But vitrectomy can also induce changes in the oxygenation of the eye. If complete detachment of the posterior vitreous can be achieved it might be possible to further slow the progression of diabetic retinopathy. CONCLUSIONS: It is possible that in the future manipulation of the vitreous by means of enzymes and lasers can play a role in the treatment and prevention of diabetic retinopathy.

Diabetic Retinopathy↗
PubMed1992

[Perimetry findings before and after surgical removal of epimacular membranes].

The visual acuity and the central visual field (Octopus program M1) were analyzed before and after peeling of epimacular membranes (EMM) in 18 eyes. The EMM were classified according to their etiology as idiopathic, secondary nonvascular and secondary vascular. A large variability of initial visual field indices was found pre- and postoperatively (table 1). The least functional improvement was found following peeling of EMM with a history of more than 12 months as well as of idiopathic EMM with an initial mean defect (MD) of greater than 3 dB (fig. 8 und 9). The best success rate was achieved for eyes with idiopathic EMM and MD less than or equal to 3 dB and for eyes with secondary nonvascular EMM (fig. 6 and 7). The visual acuity but not the MD improved postoperatively in the 3 eyes with vascular EMM which had developed after a retinal vascular branch occlusion.

Aged↗
PubMed1992

[An approach to diabetic retinopathy].

Presentation of ophthalmological taking in charge program of the diabetic patients, program elaborated during a symposium in London under the supervision of the World's Health Organisation and the International Federation of Diabetes. A calendar of the necessary controls is worked out. A scheme of the proposed treatment is decided. This program has to be known and followed by the patients, the general doctors and Swiss ophthalmologists.

Diabetic Retinopathy↗
PubMed1991

[Clinical use and results of trans-scleral Nd-YAG cyclophotocoagulation in therapy-refractory glaucoma].

We report on our results of transscleral Nd-YAG-cyclophotocoagulation on 27 eyes with refractory glaucoma. Cyclophotocoagulation was performed with similar parameters according to our findings of morphological investigation in normal human donor eyes. 9 eyes had hemorrhagic glaucoma, 10 eyes had secondary glaucoma after intraocular silicone oil tamponade because of proliferative diabetic retinopathy or because of complicated retinal detachment with proliferative vitreoretinopathy. None of the patients in this group had silicone oil in the anterior chamber, silicone oil emulsification and only one eye had rubeosis iridis. The third group of 8 eyes had glaucoma with aniridia, post-traumatic or postinflammatory glaucoma, glaucoma after extraction of a congenital cataract and one eye with an absolute painful pseudoexfoliation glaucoma. The effects were applied coaxially through the conjunctiva at 1 to 1.5 mm distance from the limbus. The energy was between 3.8 and 4.2 Joules, the exposure time was 10 ms. The focus of the laser beam was placed 3.6 mm posteriorly with a focus adjustment of 9 at the LASAG Microruptur 2. The mean postoperative observation period was 7.5 months. Among the group of hemorrhagic glaucomas the intraocular pressure could in 78% be lowered below 22 mmHg, in 60% among the secondary glaucomas after intraocular silicone oil application and in 50% among the heterogenous third group. In eyes with preceding cyclocryocoagulation 82% fulfilled this criterion. The intraocular pressure stayed stable after 4 weeks at a mean level of 40% below the preoperative values. In all cases the intraocular pressure was at least lowered by 14 mmHg. Vision was reduced in three eyes by the underlying disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Lens changes following intraocular tamponade in vitrectomy. Linear densitometric image analysis of Scheimpflug photographs 6 months after operation].

A complication arising from vitrectomy is the formation of cataract. As a result of an intra- and postoperative tamponade chosen (BSS, air, SF6-gas, silicon oil) the size and frequency of the cataract varies accordingly. 6 months after vitrectomy Scheimpflug photography and microdensitometric evaluation of the negatives were performed on 30 pairs of phacic eyes showing changes in the transparency of the lens. Following silicon oil tamponade a significant deterioration of transparency (t-test) was observed in the lens nucleus of the operated eye; in the area of the lens in front of the nucleus a marked but not significant deterioration of transparency was discovered following both silicon oil and SF6-gas tamponade. In the case of the area in front of the nucleus following SF6-gas tamponade as well as the whole of the lens following BSS or air tamponade a small but not at all significant difference in lens transparency was apparent after comparison of the operated to the non-operated eyes.

Cataract↗
PubMed1991

[Retinochoroidopathy in a patient with seropositive trichinosis].

A 28 years old butcher contracted a systemic trichinosis after fasting sausage. Twelve days after onset of systemic symptoms he developed a hemorrhagic maculopathy in his left eye. In addition, on both eyes there were focal atrophies of the retinal pigment epithelium in the mid-periphery. We believe a causal connection of the maculopathy with his serologically proven trichinosis as a retinal involvement is well known in trichinosis and histologically demonstrated by Herrenschwand (1928). To our knowledge this is the first case of hemorrhagic maculopathy in trichinosis.

Adult↗
PubMed1991

[Pathophysiology and prevention of retinopathy of prematurity].

In premature infants there is a temporal and causal relation between the change in the erythropoiesis after birth and the manifestation of retinopathy. The physiological substitution of the fetal erythrocytes can be controlled by an analysis of the fetal hemoglobin. In premature infants in which the erythropoiesis has not yet been converted there is an interval of time where there is a chronic hypoxemia of the retina and in which neovascularisation occurs. The oxygen deficit arises because fetal blood - in comparison with adult blood - exhibits a higher affinity to oxygen. If high values of HbF are ascertained in premature infants the chronic hypoxemia of the retina can be avoided by replacing the erythrocytes. In this way, a secondary prevention of the illness is possible.

Birth Weight↗
PubMed1990

[Mononuclear phagocytes and their growth factors: pacemakers of proliferative vitreoretinopathy?].

Recent studies on the natural course of proliferative vitreoretinopathy (PVR) have focused on the mononuclear phagocyte system (MPS). Although the precise origin of these cells is not known, current evidence indicates that peripheral blood monocytes infiltrate a lesion initially, subsequently giving way to resident phagocytic cells. In this context the authors try to clarify some aspects of the confusing nomenclature of phagocytic monocytes, macrophages, and microglia. The concept of the blood-retinal barrier (BRB) and its breakdown in PVR are presented and discussed. Platelet-derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta), both secretory products of macrophages, have recently been implicated in the development of vitreoretinal pathology. These studies, however, are difficult to evaluate because the biological effects of different growth factors are closely interrelated and vary widely, including both inhibition as well as stimulation of cell growth. The authors hypothesize that plasma of macrophage-derived TGF-beta provokes an increase in fibronectin synthesis, which in turn is responsible for the fibrotic rebuilding of the vitreoretinal interface in PVR. As an adjunct to the pharmacological treatment of PVR with Daunomycin the use of steroids is recommended to suppress the initial macrophage activation and related dysfunction of the BRB.

Animals↗