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1.
Eye (Lond) ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965319

RESUMEN

BACKGROUND: Age-related macular degeneration (AMD) remains a primary cause of blindness, with neovascular AMD (nAMD) presenting particular treatment challenges. Despite anti-vascular endothelial growth factor (anti-VEGF) therapies, many patients exhibit a suboptimal response to the previously available anti-vascular endothelial growth factor (anti-VEGF) therapies. This study evaluates the efficacy and treatment interval extension of faricimab in this patient cohort. METHODS: In a retrospective single-centre study at University Hospitals of Bristol and Weston, UK, nAMD patients suboptimally responsive to previous anti-VEGF therapies were switched to faricimab. Treatment started with an initiation phase of 4 monthly injections followed by a 'Treat and Extend' protocol. Outcomes included best-recorded visual acuity (BRVA), central subfield thickness (CST), the presence of retinal fluid, and treatment intervals. RESULTS: Among 98 eyes of 79 patients, following faricimab treatment, significant reductions in CST and retinal fluid were noted, indicating decreased disease activity. While BRVA changes were not statistically significant, the anatomical improvements suggest a potential therapeutic benefit. Notably, 40% of patients achieved extended treatment intervals, reducing the treatment burden. CONCLUSION: Faricimab offers a promising alternative for nAMD patients with suboptimal responses to prior anti-VEGF treatments, demonstrating significant anatomical improvements and the possibility of extended dosing intervals. These findings highlight the need for prospective real-world studies to further assess faricimab's role in nAMD management and its long-term impact on patient outcomes.

2.
Int Ophthalmol ; 40(1): 179-184, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31463623

RESUMEN

PURPOSE: The aim of the study was to evaluate retinal sensitivity and stereoacuity (SA) in retinitis pigmentosa (RP) patients. METHODS: Twenty-six patients with RP were examined, mean age 36.4 ± 7.21 (SD) years old and best corrected visual acuity better than 0.15 logMAR. The control group (CG) included 25 healthy subjects matching the RP group by age and sex. Every patient and healthy control underwent a complete ophthalmologic examination: Titmus, Lang, TNO stereotests and microperimetry (MP-1) (Nidek Technologies). Results were subjected to factor analysis using Varimax rotation, and p values < 0.05 were considered statistically significant. RESULTS: With the Titmus stereotest, the mean SA was 136.52 ± 26.5 (SD) arcsec in the RP group and 67.2 ± 11.5 (SD) in CG; Lang SA was 391.39 ± 53.72 (SD) in RP group and 1150 ± 33.4 (SD) in CG; and TNO SA was 69.3 ± 14.39 (SD) in the RP group and 15.97 ± 3.7 (SD) in CG. Factor analysis showed significant correlation between visual acuity and SA (p = 0.0001) in RP group. MP-1 demonstrated that in RP patients, inter-ocular difference in retinal sensitivity and fixation stability was related to anomalous stereopsis (p values < 0.05). CONCLUSION: Progressive RP degeneration in the cone system could determine a significant impairment in the binocular vision due to anomalous inter-ocular retinal sensitivity and incomplete Panum's area utilization, causing an incongruent retinal localization. These findings suggest a possible reason why RP patients with a central retinal involvement, even if minimal, perceive a damaged stereoscopic perception that produces a severe disability.


Asunto(s)
Percepción de Profundidad , Retina/fisiopatología , Retinitis Pigmentosa/fisiopatología , Tomografía de Coherencia Óptica/métodos , Visión Binocular/fisiología , Agudeza Visual , Adulto , Electrorretinografía , Femenino , Humanos , Masculino , Retina/patología , Células Fotorreceptoras Retinianas Conos/patología , Retinitis Pigmentosa/diagnóstico
4.
Ophthalmic Surg Lasers Imaging Retina ; 47(7): 677-81, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27434902

RESUMEN

Optical coherence tomography angiography (OCTA) provides noninvasive in vivo vascular imaging of the retina and choriocapillaris. To highlight OCTA utility, the authors align structural changes and their resolution with functional outcome. The authors present a case of acute posterior multifocal placoid pigment epitheliopathy (APMPPE) and sequential changes during transition to inactive disease. In the acute phase, altered flow and nonperfusion were seen in defined islands of choriocapillaris. Over time, progressive reperfusion was observed and accompanied clinical resolution and functional visual restoration. The imaging features acquired described the level of nonperfusion the authors had assumed when extrapolating findings from multiple independent imaging modalities. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:677-681.].


Asunto(s)
Capilares/patología , Coroides/irrigación sanguínea , Imagen Multimodal/métodos , Epitelio Pigmentado Ocular/patología , Enfermedad Aguda , Adulto , Constricción Patológica/diagnóstico , Angiografía con Fluoresceína/métodos , Fondo de Ojo , Humanos , Masculino , Enfermedades de la Retina , Tomografía de Coherencia Óptica/métodos
5.
Int Ophthalmol ; 35(5): 727-31, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26253458

RESUMEN

PURPOSE: To evaluate the visual and topographic outcomes of a two-stage approach treatment for progressive keratoconus (KC) associated with high myopia and cataract. METHODS: Two patients, a 50-year-old man and a 54-year-old woman with high myopia (spherical equivalent greater than -10D), cataract, and progressive KC with poor spectacle-corrected vision and contact lens intolerance underwent a 2-stage approach treatment: first corneal collagen cross-linking (CXL) followed after at least 6 months by phacoemulsification with intraocular lens (IOL) implantation in both eyes. RESULTS: In both patients after a mean follow-up of 3.5 years (from 2 to 4) uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and corneal topography pattern improved in both eyes, and the patients were satisfied with the visual improvement and happy with tolerable glasses. CONCLUSION: This 2-stage approach reported no complications and was effective in improving visual acuity and corneal patterns in patients with high myopia, cataract, and progressive KC.


Asunto(s)
Reactivos de Enlaces Cruzados/uso terapéutico , Queratocono/cirugía , Implantación de Lentes Intraoculares/métodos , Miopía Degenerativa/cirugía , Facoemulsificación/métodos , Catarata/fisiopatología , Colágeno/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fármacos Fotosensibilizantes/uso terapéutico , Resultado del Tratamiento , Agudeza Visual
6.
J Cataract Refract Surg ; 41(3): 527-32, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25648281

RESUMEN

PURPOSE: To evaluate the changes in corneal sensitivity after corneal collagen crosslinking (CXL) with the epithelium off (epi-off) and with the epithelium on (epi-on) in eyes with keratoconus. DESIGN: Prospective interventional case series. SETTING: Eye Clinic, A. Fiorini Hospital, Terracina (Latina), Rome, Italy. METHODS: On the basis of the corneal pachymetry at the area of topographic steepening, eyes treated with CXL were divided in 2 groups: those with a corneal thickness of 400 µm or more (epi-off) and those with a corneal thickness of less than 400 µm (epi-on). Corneal sensitivity was measured using a contact esthesiometer (Cochet-Bonnet) before treatment and 1 and 7 days and 1, 3, 6, 9, and 12 months after treatment. RESULTS: The study evaluated 50 CXL-treated eyes in 50 patients (25 epi-on and 25 epi-off) from January 7, 2012, to December 15, 2012. In the epi-off group, corneal sensitivity was statistically significantly reduced for up to 3 months after CXL and gradually returned to normal levels. In the epi-on group, corneal sensitivity was statistically significantly reduced for up to 7 days but was not statistically significantly different from preoperative values at other measurement times. At 7 days, the corneal sensitivity was statistically significantly lower in the epi-off eyes than in the epi-on eyes. CONCLUSIONS: Epi-off and epi-on CXL both caused hypoesthesia, but corneal sensitivity subsequently recovered completely. The corneal hypoesthesia was more pronounced in eyes in which the epi-off technique was used, and the recovery time was shorter for eyes treated using epi-on CXL. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.


Asunto(s)
Colágeno/metabolismo , Córnea/fisiología , Reactivos de Enlaces Cruzados , Epitelio Corneal/cirugía , Queratocono/tratamiento farmacológico , Fármacos Fotosensibilizantes/uso terapéutico , Sensación/fisiología , Adulto , Paquimetría Corneal , Topografía de la Córnea , Desbridamiento , Femenino , Humanos , Queratocono/metabolismo , Queratocono/fisiopatología , Masculino , Estudios Prospectivos , Recuperación de la Función , Riboflavina/uso terapéutico , Rayos Ultravioleta , Adulto Joven
7.
Ophthalmic Genet ; 35(1): 47-50, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23758497

RESUMEN

BACKGROUND: To determine the prevalence of macular cysts in patients with clinical cone-rod dystrophy (CORD) using spectral-domain optical coherence tomography (SD-OCT). If macular cysts could be demonstrated in such patients, they might benefit from treatment with a carbonic anhydrase inhibitor that has been shown to be effective for treating macular cysts in various night-blinding disorders. MATERIAL AND METHODS: Thirty-six CORD patients underwent a complete ophthalmic examination and an SD-OCT examination using two different systems. The presence of hypo-reflective lacunae was used to determine the presence of macular cysts. RESULTS: The patients' mean age was 42.9 ± 19.5 years (range 6-71 years). Mean BCVA was 1.09 ± 0.64 logMAR (range no light perception to 20/25 + 2 in the better-seeing eye). All the 72 eyes studied showed a variable degree of retinal thinning, disruption of what has been referred to as the inner segment ellipsoid and outer nuclear layer (ONL) thinning of the macula. None showed evidence of macular cysts on OCT testing. CONCLUSIONS: Although macular cysts are a common feature of various hereditary night-blinding retinal dystrophies, these were not identified in our cohort of CORD patients.


Asunto(s)
Quistes/epidemiología , Retinitis Pigmentosa/epidemiología , Adolescente , Adulto , Anciano , Niño , Quistes/diagnóstico , Electrorretinografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Retinitis Pigmentosa/diagnóstico , Tomografía de Coherencia Óptica , Trastornos de la Visión/diagnóstico , Agudeza Visual/fisiología , Campos Visuales/fisiología , Adulto Joven
8.
Retina ; 34(5): 989-95, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24280667

RESUMEN

PURPOSE: To evaluate dark-adapted retinal sensitivity in patients with Stargardt disease (STGD1) using a modified MP-1 microperimeter and to compare the sensitivity loss with structural changes observed using spectral domain optical coherence tomography and confocal scanning laser ophthalmoscope infrared imaging. METHODS: Twelve STGD1 patients and 10 normally sighted controls participated. Dark-adapted mean sensitivity (MS) was obtained using a MP-1 microperimeter. Additionally, MS percent difference between the patients and the controls was obtained. Sensitivity results were superimposed on confocal scanning laser ophthalmoscope infrared images and compared with corresponding spectral domain optical coherence tomography scans. RESULTS: Dark-adapted MS ± standard deviation was 8.34 ± 1.54 dB for the controls and 3.68 ± 1.74 dB for STGD1 patients (P < 0.001). There was a significant reduction in MS of 24.0% in these patients. Sensitivity reductions were observed in areas that showed changes on confocal scanning laser ophthalmoscope infrared images and on spectral domain optical coherence tomography, including disorganizational loss of the retinal pigment epithelium, and abnormal photoreceptor inner segment ellipsoid and external limiting membrane reflectance bands. CONCLUSION: With topographical accuracy, dark-adapted MS measurements can be made in STGD1 patients and controls using the MP-1 microperimeter. Sensitivity loss is associated with structural changes. This finding can be useful for the determination of optimal areas for potential improvement of retinal function in patients with Stargardt disease.


Asunto(s)
Adaptación a la Oscuridad/fisiología , Degeneración Macular/congénito , Retina/patología , Agudeza Visual/fisiología , Campos Visuales/fisiología , Adulto , Femenino , Humanos , Degeneración Macular/fisiopatología , Masculino , Persona de Mediana Edad , Oftalmoscopía , Enfermedad de Stargardt , Tomografía de Coherencia Óptica , Pruebas del Campo Visual , Adulto Joven
9.
ScientificWorldJournal ; 2013: 683090, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24298221

RESUMEN

Corneal sensitivity has recently received much attention given the crucial role the corneal nerves play in maintaining normal corneal structure and function. An increased understanding of the corneal sensitivity and dry eye disease in keratoconus, including alterations of the conjunctival cells, may help explain the pathogenesis of this disorder. There is histological evidence of the involvement of corneal nerves in the pathology of keratoconus and it has been suggested that this plays a role in the pathophysiological features and progression of the disease. In this review, the impaired corneal sensitivity found on keratoconus and corneal sensitivity changes after cross-linking performed in patients with keratoconus are reported.


Asunto(s)
Córnea/inervación , Córnea/fisiopatología , Queratocono/patología , Queratocono/fisiopatología , Nervio Oftálmico/patología , Nervio Oftálmico/fisiopatología , Sensación , Vías Aferentes/patología , Vías Aferentes/fisiopatología , Córnea/patología , Humanos
10.
Can J Ophthalmol ; 48(5): 438-42, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24093193

RESUMEN

OBJECTIVE: To evaluate the efficacy of the MP-1 microperimeter (Nidek Technologies Srl, Padova, Italy) and Visual Pathfinder (LACE Inc) in improving visual function of patients with myopic maculopathy. DESIGN: Prospective, nonrandomized, interventional case series. PARTICIPANTS: Seventeen patients (34 eyes) between 36 and 58 years of age with myopic maculopathy and central retinal scotomas. METHODS: After a complete eye examination, all patients underwent 10 training sessions with MP-1 biofeedback (7 minutes) and Visual Pathfinder (3 minutes) for each eye once a week. Statistical analysis was performed with Student t test. The p values less than 0.05 were considered statistically significant. RESULTS: The mean best corrected visual acuity increased from 0.64 ± 0.22 to 0.38 ± 0.20 logMAR at the end of follow-up (p = 0.03); visual-evoked potential P100 amplitude increased from 3.54 ± 1.90 to 6.64 ± 2.91 µV at the end of follow-up (p = 0.04); average retinal sensitivity, calculated in the 12 degrees of the central retina, increased from 6.6 ± 2.6 to 14.6 ± 3.6 dB (p = 0.03). Fixation behaviour in the 2 degrees of the central retina increased from 45% ± 17% to 75% ± 23% (p = 0.04). The bivariate contour ellipse area (95%) increased from 10.34 ± 3.11 to 7.64 ± 2.71 square degrees (p = 0.04). CONCLUSIONS: The combination of acoustic biofeedback training with MP-1 and Visual Pathfinder offers a reasonable improvement of visual function in patients with myopic maculopathy. This method might be considered as a rehabilitative strategy as a "therapeutic option" in these patients for whom most treatments usually do not work.


Asunto(s)
Biorretroalimentación Psicológica/métodos , Potenciales Evocados Visuales/fisiología , Miopía Degenerativa/rehabilitación , Enfermedades de la Retina/rehabilitación , Escotoma/rehabilitación , Agudeza Visual/fisiología , Pruebas del Campo Visual/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miopía Degenerativa/complicaciones , Miopía Degenerativa/fisiopatología , Estudios Prospectivos , Lectura , Retina/fisiopatología , Enfermedades de la Retina/etiología , Enfermedades de la Retina/fisiopatología , Escotoma/etiología , Escotoma/fisiopatología , Resultado del Tratamiento
11.
Surv Ophthalmol ; 58(6): 560-84, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24160730

RESUMEN

Cystic macular lesions frequently contribute to impaired visual acuity in hereditary retinal dystrophies. Their pathogenesis varies and is not entirely understood. Carbonic anhydrase inhibitors have proven to be potentially efficacious, although not in all cases. We discuss the various factors and mechanisms implicated in the etiology of cystic macular lesions (anatomical abnormalities, impairment of the blood-retinal barrier, tangential vitreous traction, and mutations in retinoschin, etc.) and the various treatments that have been proposed.


Asunto(s)
Coroideremia/complicaciones , Enfermedades Hereditarias del Ojo/complicaciones , Atrofia Girata/complicaciones , Edema Macular/tratamiento farmacológico , Degeneración Retiniana/complicaciones , Retinitis Pigmentosa/complicaciones , Retinosquisis/complicaciones , Trastornos de la Visión/complicaciones , Inhibidores de Anhidrasa Carbónica/uso terapéutico , Humanos , Edema Macular/diagnóstico , Edema Macular/etiología
12.
Appl Psychophysiol Biofeedback ; 38(1): 11-6, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22903517

RESUMEN

In this study we evaluated the efficacy of visual rehabilitation by means of two different types of biofeedback techniques in patients with age related macular degeneration (AMD). Thirty patients, bilaterally affected by AMD, were randomly divided in two groups: one group was treated with an acoustic biofeedback (AB group), the other was treated with luminous biofeedback of a black and white checkerboard flickering during the examination (LB group). All patients underwent a complete ophthalmological examination. Rehabilitation consisted of 12 training sessions of 10 min for each eye performed once a week for both groups. Both groups showed better visual performance after rehabilitation and luminous flickering biofeedback stimulus showed a statistically significant improvement in training the patients to modify their preferred retinal locus in comparison to acoustic biofeedback. This suggests that it might be possible in the damaged retina to override dead photoreceptor and outer retinal layers and involve residual surviving cells, as well as amplify and integrate retinal and brain cortex plasticity by using other spared channels towards associative pathways.


Asunto(s)
Biorretroalimentación Psicológica/métodos , Degeneración Macular/rehabilitación , Estimulación Acústica , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa , Resultado del Tratamiento
13.
Int Ophthalmol ; 31(5): 417-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22102213

RESUMEN

In this study, we investigated the visual performance of two aspherical intraocular lenses (IOLs), Tecnis ZCB00 and Acrysof SN60WF, by measuring high-order aberration, visual evoked potentials (VEP), retinal sensitivity, and fixation stability by MP-1 microperimetry and contrast sensitivity values. Twenty-two patients with age-related cataract were randomly allocated to either the Tecnis or the Acrysof group. All measurements were taken from patients of both groups 2 months postoperatively. Statistical analysis was performed with Student's t test, where P-values < 0.05 were considered significant. Results were not statistically significant with regard to high-order aberration, VEP, retinal sensitivity, and fixation stability. However, the contrast sensitivity values varied significantly between Tecnis ZCB00 and Acrysof SN60WF, with Tecnis ZCB00 performing better. The anterior aspherical surface design of the Tecnis IOL indicated better mesopic contrast sensitivity at mediate and high frequencies, ensuring a better quality of vision after cataract surgery.


Asunto(s)
Extracción de Catarata , Lentes Intraoculares , Seudofaquia/fisiopatología , Agudeza Visual/fisiología , Aberrometría , Anciano , Sensibilidad de Contraste/fisiología , Potenciales Evocados Visuales/fisiología , Femenino , Fijación Ocular/fisiología , Humanos , Implantación de Lentes Intraoculares , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
14.
Clin Ophthalmol ; 5: 1269-72, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21966199

RESUMEN

PURPOSE: To evaluate the usefulness of acoustic biofeedback by means of Mozart's Sonata for Two Pianos in D Major K. 448 to maintain and/or restore visual performance in a patient with macular pucker and glaucoma. METHODS: A 74-year-old patient with open angle glaucoma in both eyes and macular pucker in the right eye (RE) underwent visual rehabilitation with acoustic biofeedback by means of the MAIA™ Vision Training Module (Centervue, Padova, Italy) 10 minutes each eye once a week for 5 weeks. The patient was asked to move his eyes according to a sound which changed into Mozart's Sonata for Two Pianos when the patient locked the fixation target. RESULTS: Best-corrected visual acuity improved in his right eye (RE) and was stable in the left eye (LE). Fixation stability improved in both eyes, and retinal sensitivity decreased in the RE and improved in the LE. The characteristic of the macular pucker did not change during the training as demonstrated with optical coherence tomography. The patient was very satisfied with the training, as demonstrated by a 25-item questionnaire (National Eye Institute - Visual Functioning Questionnaire, NEI-VFQ-25). The patient's reading speed and the character size which he was able to read improved in his RE. CONCLUSION: Music could enhance synaptic plasticity and affect neural learning and fixation training by means of MAIA vision training. Therefore it can improve visual performance in patients with macular pucker, postpone the surgical time, and assure a better quality of life for the patient.

15.
Clin Ophthalmol ; 5: 1007-10, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21845025

RESUMEN

BACKGROUND: The purpose of the study was to evaluate vitreoretinal interface (VRI) alteration with a short-wavelength scanning laser ophthalmoscope (swSLO), the Nidek F-10, and compare the results with those obtained by means of spectral-domain optical coherence tomography (SD-OCT). METHODS: Thirty-six eyes were studied (20 patients, mean age 68 ± 12.3 years). All patients underwent a complete ophthalmologic examination, which comprised SD-OCT and Nidek F-10 analysis with short-wavelength blue laser. Eyes were divided into four groups depending on the degree of VRI alteration observed with the swSLO and SD-OCT. Statistical analysis was performed using the Chi-square test. P values less than 0.05 were considered statistically significant. RESULTS: OCT ANALYSIS: eight eyes (22%) grade 0 (no abnormalities), 15 eyes (42%) grade 1 (preretinal cellophane); seven (19%) grade 2 (preretinal wrinkling); six (17%) grade 3 (macular pucker or hole). Nidek F-10 analysis: seven (19%) grade 0, 16 (45%) grade 1; seven (19%) grade 2; six (17%) grade 3. Chi-square = 0.099, P = 0.992. There was no statistically significant difference between the two instruments. CONCLUSION: Nidek F-10 allows both a quantitative and a qualitative evaluation of VRI and is equal to SD-OCT in detecting alteration of the inner portion of the retina, providing an easy way to evaluate and map differences in the inner vitreoretinal surface.

16.
J Pediatr Ophthalmol Strabismus ; 47 Online: e1-3, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-21158358

RESUMEN

Alström syndrome is a multisystemic disorder characterized by cone-rod dystrophy, hearing loss, obesity, insulin resistance and hyperinsulinemia, type 2 diabetes mellitus, dilated cardiomyopathy, and progressive hepatic and renal dysfunction. The cone-rod retinal dystrophy usually develops within a few weeks after birth. The authors examined a young boy with Alström syndrome by means of microperimetry and spectral domain optical coherence tomography (OCT). Instead of the typical alterations observed in cone-rod dystrophies, the characteristics of the central foveal tissue suggest signs of retinal immaturity, with only a single layer of short, thick cones and rods and immature short outer segments. High-speed and high-resolution spectral domain OCT allowed a detailed analysis of retinal layers in a young patient with Alström syndrome for the first time.


Asunto(s)
Síndrome de Alstrom/diagnóstico , Retina/fisiopatología , Distrofias Retinianas/diagnóstico , Tomografía de Coherencia Óptica , Síndrome de Alstrom/fisiopatología , Preescolar , Pruebas de Percepción de Colores , Electrorretinografía , Humanos , Masculino , Distrofias Retinianas/fisiopatología , Agudeza Visual/fisiología , Pruebas del Campo Visual , Campos Visuales/fisiología
17.
J Ophthalmol ; 2010: 354645, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21461356

RESUMEN

Endothelin is a potent vasoactive peptide occurring in three isotypes, ET-1, ET-2, and ET-3. Through its two main receptors, endothelin A and endothelin B, it is responsible for a variety of physiological functions, primarily blood flow control. Recent evidence from both human and animal models shows involvement of endothelin in diabetes, retinal circulation, and optic neuropathies. Increased circulating levels of endothelin-1 (ET-1) have been found in patients with diabetes, and a positive correlation between plasma ET-1 levels and microangiopathy in patients with type-2 diabetes has been demonstrated. In addition to its direct vasoconstrictor effects, enhanced levels of ET-1 may contribute to endothelial dysfunction through inhibitory effects on nitric oxide (NO) production. Experimental studies have shown that chronic ET-1 administration to the optic nerve immediately behind the globe causes neuronal damage, activation of astrocytes, the major glial cell in the anterior optic nerve, and upregulation of endothelin B receptors. This paper outlines the ubiquitous role of endothelin and its potential involvement in ophthalmology.

18.
Appl Psychophysiol Biofeedback ; 34(2): 127-33, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19396541

RESUMEN

Macular disease is one of the main causes of visual impairment. We studied the efficacy of low-vision rehabilitation by means of MP-1 biofeedback examination in patients with different macular disease. Five patients were enrolled (3 female and 2 male, mean age 53.8 years) and a total of 9 eyes was examined: 2 eyes with vitelliform dystrophy, 1 with a post-traumatic macular scar, 2 with Stargardt disease, 2 with myopic macular degeneration, 2 with cone dystrophy. All the patients underwent the following tests: visual acuity, reading speed, fixation test, MP-1 microperimetry. Low-vision rehabilitation, which lasted 10 weeks, consisted of 10 training sessions of 10 min for each eye, performed once a week using the MP-1 biofeedback examination. Statistical analysis was performed using Student's t-test. p values less than 0.05 were considered statistically significant. After training all patients displayed an improvement in visual acuity, fixation behaviour, retinal sensitivity and reading speed. Fixation behaviour within the 2 degrees diameter circle improved and was statistically significant for reading speed (p = 0.01). Reading speed improved from a mean value of 64.3 to 92 words/min. Our results show that audio feedback can, by increasing attentional modulation, help the brain to fix the final preferred retinal locus. Audio feedback facilitates stimuli transmission between intraretinal neurons as well as between the retina and brain, which is where the highest level of stimuli processing occurs, thereby probably supporting a "remapping phenomenon".


Asunto(s)
Biorretroalimentación Psicológica/instrumentación , Degeneración Macular/rehabilitación , Trastornos de la Visión/rehabilitación , Adulto , Anciano , Angiografía , Femenino , Fijación Ocular/fisiología , Humanos , Degeneración Macular/patología , Masculino , Persona de Mediana Edad , Músculos Oculomotores/fisiología , Proyectos Piloto , Lectura , Retina/fisiopatología , Vasos Retinianos/fisiología , Escotoma/patología , Encuestas y Cuestionarios , Tomografía de Coherencia Óptica , Trastornos de la Visión/patología , Agudeza Visual/fisiología
20.
Int Ophthalmol ; 29(5): 423-5, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18568294

RESUMEN

The optic nerve head pit is a congenital anomaly of the optic disc due to imperfect closure of the superior edge of the embryonic fissure. We studied in detail by means of fluorescein angiography (FLA), microperimetry (fundus related perimetry), and ocular coherence tomography (OCT) the case of a 30-year-old woman who had an optic pit with secondary retinoschisis in her right eye.


Asunto(s)
Disco Óptico/anomalías , Retinosquisis/etiología , Pruebas del Campo Visual/métodos , Adulto , Anomalías del Ojo/complicaciones , Anomalías del Ojo/diagnóstico , Femenino , Angiografía con Fluoresceína , Fondo de Ojo , Humanos , Retinosquisis/diagnóstico , Tomografía de Coherencia Óptica
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