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1.
Klin Monbl Augenheilkd ; 212(5): 311-3, 1998 May.
Artículo en Alemán | MEDLINE | ID: mdl-9677565

RESUMEN

PURPOSE: To measure critical (foveal) flicker fusion frequencies (CFF) in normal eyes, unilateral maculopathies and neuropathies and in orthoptic amblyopias. METHODS: A newly developed apparatus (4F) with LED's measured subjective foveal CFF by ascending and descending mode in a group of normals and patients. RESULTS: The apparatus (4F) measures temporal resolution. Foveal CFF ist more reduced in neuropathies than in maculopathies. In contrast, CFF in amblyopic eyes is hardly reduced, in most cases equal or better than in the dominant fellow eye. This is independent from the visual acuity of the amblyopic eye. CONCLUSION: CFF testing is useful in the evaluation of unexplained (unilateral) reduction of visual acuity. A dissociation between visual acuity and CFF (within normal range) is present in cases of amblyopia.


Asunto(s)
Ambliopía/diagnóstico , Fusión de Flicker/fisiología , Mácula Lútea , Enfermedades del Nervio Óptico/diagnóstico , Enfermedades de la Retina/diagnóstico , Ambliopía/fisiopatología , Diagnóstico Diferencial , Humanos , Mácula Lútea/fisiopatología , Enfermedades del Nervio Óptico/fisiopatología , Enfermedades de la Retina/fisiopatología , Umbral Sensorial/fisiología , Agudeza Visual/fisiología
2.
Klin Monbl Augenheilkd ; 204(5): 391-3, 1994 May.
Artículo en Francés | MEDLINE | ID: mdl-8051879

RESUMEN

In cases of senile ectropion the orbicularis muscle and the skin of the lower eyelid lose their elasticity and tonus. After excision of the conjunctiva and the tarsus, enlarged by granulomatous inflammation, the free posterior border of the lower eyelid is nicely applied against the eyeball and the lower eyelid recovers its elasticity and practically normal tonus. Often excess fibro-elastic tissue forms a spontaneous vertical fold over a distance half of the distance over which the eyelid should have been shortened. Excision of the excess tucked lower eyelid tissue results in a highly satisfactory esthetic and functional cure.


Asunto(s)
Ectropión/cirugía , Anciano , Ectropión/etiología , Ectropión/patología , Epitelio/patología , Párpados/patología , Párpados/cirugía , Humanos , Metaplasia , Tono Muscular/fisiología , Técnicas de Sutura
3.
J Cell Sci ; 104 ( Pt 1): 211-8, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8449999

RESUMEN

Mitogenic activities of human retinal pigment epithelial cell-conditioned medium (HRPE-CM) with different effects, such as inhibition, stimulation or no effect, on the proliferation of vascular endothelial cells (EC) in vitro have been reported. In this study, 14 HRPE cell lines were established from normal human eyes. Human umbilical vein endothelial cells (HUVEC) in the early passages were used as target cells to detect the mitogenic activity of HRPE-CM on the growth of vascular EC. Our results confirm that HRPE cells in culture continuously synthesize and secrete HUVEC growth substance(s) into a serum-free medium. The ability of HRPE cell lines to produce this mitogen seem unrelated either to in vivo donor factors or to in vitro cell life span. Using an enzyme-linked immunosorbance assay, we demonstrated that only HRPE cell extract, not HRPE-CM, can be recognized by basic fibroblast growth factor (bFGF)-specific antibody, though identical bioactivities on the growth of HUVEC were found in both preparations. The active component in HRPE-CM was heat- and trypsin-sensitive, and stable at extremes of pH (2.5 to 10.0). In addition, the bioactive molecule could not pass through a M(r) 30,000 cut-off membrane, suggesting that it is a fairly high molecular mass polypeptide. These observations suggest that the EC growth factor in HRPE-CM is distinct from fibroblast growth factors (FGFs).


Asunto(s)
Mitógenos/metabolismo , Epitelio Pigmentado Ocular/citología , División Celular/efectos de los fármacos , Células Cultivadas , Inhibición de Contacto/efectos de los fármacos , Medios de Cultivo Condicionados/farmacología , Medio de Cultivo Libre de Suero , Endotelio Vascular/citología , Humanos , Recién Nacido , Mitógenos/aislamiento & purificación , Mitógenos/farmacología , Epitelio Pigmentado Ocular/metabolismo , Estimulación Química , Venas Umbilicales
4.
Klin Monbl Augenheilkd ; 200(5): 525-8, 1992 May.
Artículo en Francés | MEDLINE | ID: mdl-1614146

RESUMEN

Optic neuropathy during non-Hodgkin lymphoma is a late central nervous system complication of unfavourable prognosis. It appears especially with involvement of the bone marrow. A normal cerebrospinal fluid, lack of any beneficial effect of the chemo-corticotherapy and absence of papilledema suggest paraneoplastic, or iatrogenic (radio and (or) chemotherapeutic) neuropathy with conclusive histopathological proof only at autopsy. More frequently, cerebrospinal fluid containing malignant cells, papilledema and a beneficial effect of the chemocortico-therapy suggests malignant infiltration of the optic nerve as occurs in our case. Optic neuropathy during non-Hodgkin lymphoma may exceptionally precede the systemic disease by several years. Early oculomotor involvement suggests meningeal malignant infiltration as found in meningeal carcinomatosis.


Asunto(s)
Linfoma no Hodgkin/patología , Neuritis Óptica/diagnóstico , Síndromes Paraneoplásicos/diagnóstico , Potenciales Evocados Visuales/fisiología , Humanos , Masculino , Persona de Mediana Edad , Nervio Óptico/patología , Neuritis Óptica/patología , Síndromes Paraneoplásicos/patología , Agudeza Visual/fisiología
5.
Bull Soc Belge Ophtalmol ; 244: 1-16, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1297505

RESUMEN

Loss of mainly field in POAG is due to Schnabel's cavernous atrophy of the axons at their scleral passage, built up by aligned stacks of glial collagen (IV and I) tissue plates, which contain capillaries. Organisation, size and structural surroundings encircle isolated or grouped axons not evenly distributed. The stereotype pattern of fieldloss linked to a characteristic optic nerve lesion suggests POAG be considered a N.O. disease as raised IOP may be only one of the risk factors. Are cavernous atrophy (loss of field) and the trabecular spaces narrowing (rise of IOP) both the result of the same pathogenic mechanism acting on the collagen fiber (IV and I) of the scleral coat, resp. lamina cribrosa (posterior segment) and trabecular meshwork (anterior segment)? If so, IOP-rise only worsens the condition as will do a hemodynamic energy crisis at the level of the axons. Interactive dominance at any of both levels may explain unexpected discrepancies between IOP and fieldloss. Considering "to treat or not to treat" accurate field loss predictability testing, urgent research topic, are discussed.


Asunto(s)
Glaucoma de Ángulo Abierto/fisiopatología , Presión Intraocular , Cámara Anterior/fisiopatología , Humanos , Disco Óptico/patología , Disco Óptico/fisiopatología , Arteria Retiniana/fisiopatología , Malla Trabecular/fisiopatología , Campos Visuales
6.
Graefes Arch Clin Exp Ophthalmol ; 230(4): 358-61, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1505768

RESUMEN

While spatial resolution may be easily assessed with contrast-sensitivity frequency (CSF) data, determination of foveal flicker-fusion frequency (4F) is a simple method of providing the ophthalmic practitioner with accurate information about temporal resolution. The authors describe a simple apparatus that controls luminance, light intensity, light intervals, stimulus size, homogeneity of background illumination, and binocular gaze, especially when using two wavelengths, allowing an increased number of applications with reliable and comparable results. It may prove to be a useful tool for screening, clinical and subclinical assessment, and for evaluating visual acuity, also during follow-up.


Asunto(s)
Fusión de Flicker/fisiología , Fóvea Central , Oftalmología/instrumentación , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa , Umbral Sensorial , Agudeza Visual/fisiología
7.
Klin Monbl Augenheilkd ; 198(5): 377-81, 1991 May.
Artículo en Francés | MEDLINE | ID: mdl-1886361

RESUMEN

The isolated presumably inflammatory involvement mostly acute and unilateral of the photoreceptor layer of the retina, in the macular region, has been described as clinical entity: macular neuroretinopathy. Three cases are presented. Its evolution, ophthalmoscopic appearance (cuneiform tear drop), negative angiofluorography, normal electroophthalmography, differentiates neuroretinopathy from cystoid edema (CME), retinoschisis, acute macular multifocal placoid pigmentepitheliopathy, pigmentepitheliitis, and "Multiple evanescent white dot syndrome" (MEWDS). Visual acuity is mildly decreased but its recovery is poor even after a long period of time. Secondarily the pigmentepithelium may be involved. MEWDS is characterised by a primary fruste involvement of the pigmentepithelial layer simultaneously with a secondary involvement of the choriocapillaris, and possibly photoreceptor layer.


Asunto(s)
Mácula Lútea , Retinitis/diagnóstico , Adulto , Femenino , Angiografía con Fluoresceína , Humanos , Mácula Lútea/patología , Mácula Lútea/fisiopatología , Masculino , Epitelio Pigmentado Ocular/patología , Epitelio Pigmentado Ocular/fisiopatología , Vasos Retinianos/patología , Vasos Retinianos/fisiopatología , Retinitis/patología , Retinitis/fisiopatología , Escotoma/diagnóstico , Escotoma/patología , Escotoma/fisiopatología , Campos Visuales/fisiología
8.
Biophys J ; 59(2): 433-44, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2009358

RESUMEN

The application of photon correlation spectroscopy on mammalian eye lenses in vivo is revisited. It is shown that the use of a short wavelength laser type and a logarithmic correlator improves the signal-to-noise ratio to such an extent that shorter measurement times are possible without impairing the information content of the correlation function. Experimental correlation functions obtained in vivo on a rabbit eye lens, are analyzed with several techniques. The histogram approach is most successful for the determination of the distribution function of relaxation processes in the correlation function and proposes four different populations of components in the lens. This result is comparable to that from in vitro measurements on highly concentrated solutions of alpha-crystallins and of fiber cell cytoplasm, the former proteins being the main scattering components both in vivo and in vitro in the eye lens system. Our results indicate that the application of photon correlation spectroscopy on eye lenses in vivo offers new perspectives to use this technique as a fast, noninvasive tool to study relaxation phenomena in normal and cataractous lenses. The sensitivity of the method allows it to be used as an important analytical technique in the study of prevention and treatment of cataract.


Asunto(s)
Cristalino/fisiología , Absorciometría de Fotón , Animales , Rayos Láser , Luz , Matemática , Conejos
9.
Ophtalmologie ; 4(1): 4-7, 1990.
Artículo en Francés | MEDLINE | ID: mdl-2250938

RESUMEN

The authors suggest the production by the cultured RPE cell of one or more angiogenic substances. This activity is highly increased when RPE are cultured in poor conditions, either due to a poor medium or after having been challenged by a high number of rod outer segments. The mitotic factor appears heat-labile and trypsine sensitive, but not dialysable which suggest their biochemical nature to be a protein.


Asunto(s)
Endotelio Vascular/citología , Sustancias de Crecimiento/biosíntesis , Mitosis/fisiología , Epitelio Pigmentado Ocular/metabolismo , Anciano , Comunicación Celular/fisiología , Células Cultivadas , Humanos , Persona de Mediana Edad
10.
Ophtalmologie ; 3(1): 69-72, 1989.
Artículo en Francés | MEDLINE | ID: mdl-2641076

RESUMEN

A complete uveal dysgenesis with absence of the anterior chamber and fixed mydriatic pupil was observed in the left eye of a boy. His younger sister and his father, and also the right eye of the patient showed similar but more discrete anterior uveal alterations. All three persons present some facial peculiarities. They are also heterozygous for a paracentric inversion of the short arm of chromosome 3. Four other cases with this chromosomal aberration were found in the literature, none with eye anomalies.


Asunto(s)
Aberraciones Cromosómicas/genética , Inversión Cromosómica , Cromosomas Humanos Par 3 , Enfermedades de la Úvea/genética , Aberraciones Cromosómicas/diagnóstico , Aberraciones Cromosómicas/patología , Trastornos de los Cromosomas , Citogenética , Humanos , Lactante , Masculino , Oftalmoscopía , Enfermedades de la Úvea/diagnóstico , Enfermedades de la Úvea/patología
12.
Arch Neurol ; 45(9): 1046-7, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3415523

RESUMEN

Apparent sustained lid lag appears to be a peculiar neuro-ophthalmologic finding in Guillain-Barré-Strohl syndrome. We propose that the sign occurs with peripheral facial paralysis and it results after attempted forced lid closure, rather than being of central origin.


Asunto(s)
Párpados/fisiopatología , Parálisis Facial/fisiopatología , Polineuropatías/fisiopatología , Adulto , Electromiografía , Electronistagmografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome
13.
Experientia ; 44(8): 702-4, 1988 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-3410002

RESUMEN

Sucrose, nycodenz, metrizamide and a mixture of equal volumes of sucrose and metrizamide were used as density gradient media for the isolation of retinal rod outer segments. The high osmolarity of sucrose had a strongly negative effect on the nature of the rod outer segments, whereas they were much better preserved using iodinated density gradient media such as nycodenz and metrizamide for their isolation.


Asunto(s)
Células Fotorreceptoras , Segmento Externo de la Célula en Bastón , Animales , Bovinos , Fraccionamiento Celular/métodos , Centrifugación por Gradiente de Densidad/métodos , Yodo , Microscopía Electrónica
14.
Klin Monbl Augenheilkd ; 192(5): 551-4, 1988 May.
Artículo en Francés | MEDLINE | ID: mdl-3404964

RESUMEN

Certain patients with reduction or loss of central visual function and/or hemianopic changes of the visual field can be classified as well-informed malingerers, individuals who are easily influenced by suggestion, or neurotics suffering from "conversion hysteria." The main symptom is one of a functional sensory change (loss or reduction of visual field). The task falling to the ophthalmologist is to prove the contrary, using certain subjective and objective tests to prove the incompatibility of the results with the physiological facts. The authors discuss the specificity of these tests in this context and present a number of cases with the characteristic temporal or nasal functional hemianopsia comparing them with patients who have hemianopsias due to real anatomic lesions.


Asunto(s)
Trastornos de Conversión/psicología , Dominancia Cerebral , Hemianopsia/psicología , Adolescente , Adulto , Conmoción Encefálica/psicología , Estudios de Seguimiento , Humanos , Masculino , Campos Visuales
16.
Klin Monbl Augenheilkd ; 192(2): 157-62, 1988 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-2834602

RESUMEN

The present paper describes a 62-year-old male patient with progressive night blindness and generalized peripheral neuropathy linked to HLA A29 and HLA B12. Multiple yellowish patches, radiating from the optic disk, were observed at the level of the retina, though they were not clearly outlined during angiofluorography. No signs nor symptoms of inflammation were present. There was also a discrepancy between the visual field and the objective ophthalmoscopic findings. The author has coined the term inner neuroretinopathy to define this phenomenon. Differential diagnosis with birdshot and vitiliginous retinopathy is extensively discussed.


Asunto(s)
Antígenos HLA-A , Antígenos HLA-B , Ceguera Nocturna/complicaciones , Enfermedades del Sistema Nervioso Periférico/complicaciones , Enfermedades de la Retina/complicaciones , Diagnóstico Diferencial , Electrorretinografía , Angiografía con Fluoresceína , Antígenos HLA/análisis , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Enfermedades del Sistema Nervioso Periférico/genética , Enfermedades de la Retina/diagnóstico
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