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1.
BMC Ophthalmol ; 15: 173, 2015 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26645589

RESUMEN

BACKGROUND: One of the most challenging problems in vitro-retinal surgery is the recurrence of retinal detachment in the context of high-grade proliferative vitreoretinopathy (PVR). The aim of our retrospective study was to assess the surgical outcomes of pars plana vitrectomy, 180° inferior retinotomy and silicone oil tamponade combined with phacoemulsification and IOL implantation for recurrent inferior retinal detachment with grade C PVR in phakic eyes. The study was carried out at tertiary referral centre - University Hospital of Rome "Tor Vergata". METHODS: Retrospective analysis of 33 eyes affected by recurrent inferior retinal detachment and grade C PVR after primary encircle scleral buckling (SB group - 12 eyes), or pars plana vitrectomy (PPV group - 21 eyes). All patients subsequently underwent PPV and silicone oil tamponade at our Institution. The first outcome measure was retinal reattachment, and second outcomes were reoperation rates, best-corrected visual acuity (BCVA) and postoperative complications. RESULTS: All patients in the SB group and 19 (90%) patients of the PPV group achieved retinal reattachment. Final BCVA was better in the SB group (p = 0.045). Two eyes in the PPV group required a third vitrectomy with heavy silicone oil tamponade. Postoperative complications included silicone oil in a deep anterior chamber (3 eyes in each group), untreatable hypotony in 1 eye in the PPV group (that led to enucleation due to phthisis bulbi), and elevated intraocular pressure in 3 patients (2 eyes in the PPV group). CONCLUSIONS: Phacoemulsification with IOL implant, PPV with silicone oil tamponade associated with 180° inferior retinotomy may lead to better anatomical success in patients who have previously undergone SB procedure for inferior retinal detachment repair compared with eyes that underwent a primary PPV.


Asunto(s)
Endotaponamiento , Retina/cirugía , Desprendimiento de Retina/cirugía , Curvatura de la Esclerótica , Aceites de Silicona/administración & dosificación , Vitrectomía , Vitreorretinopatía Proliferativa/cirugía , Adulto , Anciano , Femenino , Humanos , Implantación de Lentes Intraoculares , Masculino , Persona de Mediana Edad , Facoemulsificación , Complicaciones Posoperatorias , Recurrencia , Retina/fisiopatología , Desprendimiento de Retina/fisiopatología , Estudios Retrospectivos , Líquido Subretiniano , Agudeza Visual/fisiología , Vitreorretinopatía Proliferativa/clasificación , Vitreorretinopatía Proliferativa/fisiopatología
2.
Front Neurosci ; 9: 479, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26733792

RESUMEN

AIM: To assess the frequency of glaucoma-like alterations in Alzheimer's disease (AD) patients using Heidelberg Retinal Tomograph III (HRT-3) and Frequency Doubling Technology (FDT) perimetry. METHODS: The study included 51 eyes of 51 AD subjects and 67 eyes of 67 age- and sex-matched controls. Subjects underwent an ophthalmological examination including measurements of intraocular pressure (IOP), Matrix FDT visual field testing, optic nerve head morphology and retinal nerve fiber layer thickness (RNFLt) assessment by slit-lamp biomicroscopy and HRT-3. RESULTS: The frequency of alterations was significantly higher in the AD group (27.5 vs. 7.5%; p = 0.003; OR = 4.69). AD patients showed lower IOP (p = 0.000) despite not significantly different values of central corneal thickness (CCT) between the groups (p = 0.336). Of all the stereometric parameters measured by HRT-3, RNFLt was significantly lower in AD patients (p = 0.013). This group also had significantly worse results in terms of Moorfields Regression Analysis (p = 0.027). Matrix showed significantly worse Mean Deviation (MD) (p = 0.000) and Pattern Standard Deviation (PSD) (p = 0.000) values and more altered Glaucoma Hemifield Test (p = 0.006) in AD patients. Pearson's R correlation test showed that Mini Mental State Examination is directly correlated with MD (R = 0.349; p = 0.034) and inversely correlated with PSD (R = -0.357; p = 0.030). CONCLUSION: Patients with AD have a higher frequency of glaucoma-like alterations, as detected by the use of HRT-3. These alterations were not associated with elevated IOP or abnormal CCT values.

3.
Eur J Ophthalmol ; 24(3): 358-63, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24338580

RESUMEN

PURPOSE: To assess eye movements pattern during reading process in patients with primary open-angle glaucoma (POAG) using a microperimeter. METHODS: Thirty-two patients with POAG at early and moderate stage, according to Glaucoma Staging System 2, and 34 healthy age- and sex-matched subjects were included in the study. Reading speed and accuracy were previously evaluated with specific tests adjusted for age. In addition, all participants performed a reading test with Microperimeter Nidek MP1. Ocular movements during the reading process were recorded and values of maximum and minimum eye movements along the horizontal (Xmax and Xmin) and vertical (Ymax and Ymin) axis and mean ocular movement speed were provided by the MP1. RESULTS: There were significant differences between patients with and without POAG in terms of Xmax and Ymax eye movement values (4.75 ± 2.57 versus 3.38 ± 0.67, p = 0.003; and 4.39 ± 1.43 versus 3.34 ± 0.52, p<0.001, respectively). These differences were significant even comparing only stage 1 patients to controls. There were no significant differences in Xmin and Ymin values and mean ocular movement speed between the 2 groups. CONCLUSIONS: The study showed significant differences in eye movements pattern in patients with POAG during the reading test performed with the MP1 when compared to the control group. These alterations may be partly the consequence of the neurodegenerative process of the central visual pathway in glaucoma.


Asunto(s)
Movimientos Oculares/fisiología , Glaucoma de Ángulo Abierto/fisiopatología , Trastornos de la Motilidad Ocular/fisiopatología , Lectura , Pruebas del Campo Visual , Campos Visuales/fisiología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Agudeza Visual/fisiología
4.
J Glaucoma ; 21(1): 1-6, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21173704

RESUMEN

PURPOSE: To assess the 12-year incidence of glaucoma and glaucoma-related visual field loss in a population-based cohort study. PATIENTS: In 2000, we reexamined 411 of the 581 survivors from the original Ponza eye study conducted in 1988. METHODS: Primary open-angle (POAG), primary angle-closure (PACG), and secondary [pseudoexfoliative (PEX)] glaucoma were diagnosed according to the 3-tiered system of evidence developed by the International Society of Geographical and Epidemiological Ophthalmology. Severity of glaucoma was classified according to the Bascom-Palmer system. Visual loss was defined according to World Health Organization guidelines. Relative risk ratios were calculated for several variables. RESULTS: The 12-year incidence of definite POAG was 3.8% (95% confidence intervals (CI), 2.3-6.2), that is, an average annual rate of 0.32%. Corresponding rates for PACG and PEX glaucoma were 0.5% (95% CI, 0.1-1.8) and 0.8% (95% CI, 0.3-2.2), respectively. Half the incident glaucoma cases (45%) had not been diagnosed earlier. Fifty-five percent of the incident POAG eyes had Bascom-Palmer stage 1 or 2 disease and 40% of the incident PACG or PEX glaucoma eyes had stage 3 or 4 disease. Seven of 20 incident glaucoma cases presented with monocular or binocular visual loss because of advanced visual field loss. Significant risk factors for POAG included high myopia (>6.0 D), intraocular pressure ≥22 mm Hg, and glaucoma family history. CONCLUSION: The average annual incidence of definite POAG in Ponzas lower than that reported in persons of African ancestry and higher than that observed in certain other white populations.


Asunto(s)
Síndrome de Exfoliación/epidemiología , Glaucoma de Ángulo Cerrado/epidemiología , Glaucoma de Ángulo Abierto/epidemiología , Trastornos de la Visión/epidemiología , Campos Visuales , Adulto , Anciano , Anciano de 80 o más Años , Síndrome de Exfoliación/diagnóstico , Reacciones Falso Positivas , Femenino , Glaucoma de Ángulo Cerrado/diagnóstico , Glaucoma de Ángulo Abierto/diagnóstico , Humanos , Incidencia , Presión Intraocular , Italia/epidemiología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Valor Predictivo de las Pruebas , Factores de Tiempo , Agudeza Visual/fisiología
5.
Mol Vis ; 17: 1298-304, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21633716

RESUMEN

PURPOSE: To evaluate levels of malondialdehyde and the total antioxidant capacity (TAC) in the blood, aqueous humor, and vitreous bodies of diabetic and nondiabetic patients. We also measured the blood energy charge potential (ECP). METHODS: We examined 19 patients with type 2 diabetes mellitus and diabetic retinopathy. Ten were scheduled for cataract surgery and pars plana vitrectomy because of proliferative diabetic retinopathy (PDR). The other nine, with mild nonproliferative PDR (NPDR), and fourteen nondiabetic, age-matched subjects enrolled as a control group were scheduled for cataract surgery and vitrectomy because of epiretinal membranes. Blood, aqueous humor and vitreous body samples were collected at the time of surgery. Malondialdehyde concentrations and blood ECP were measured with high-performance liquid chromatography. The TAC of the samples was estimated with the oxygen radical absorbance capacity method. RESULTS: The level of blood and vitreous malondialdehyde in the PDR group was significantly higher compared to controls and to NPDR patients. PDR patients also had lower levels of TAC at the vitreous body and aqueous humor level, but not at the blood level, compared to controls and with NPDR patients. In all diabetic patients, the blood ECP values were significantly lower, compared to control subjects. CONCLUSIONS: Our data support the hypothesis that oxidative stress and the decrease of antioxidant defenses are associated with the progression of diabetic retinopathy to its proliferative form. Antioxidant supply may have the effect of correcting oxidative stress and inhibiting disease progression.


Asunto(s)
Antioxidantes/análisis , Humor Acuoso/química , Retinopatía Diabética/metabolismo , Peroxidación de Lípido , Cuerpo Vítreo/química , Anciano , Análisis Químico de la Sangre , Cromatografía Líquida de Alta Presión , Diabetes Mellitus Tipo 2 , Retinopatía Diabética/fisiopatología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Malondialdehído/análisis , Estrés Oxidativo
6.
J Cataract Refract Surg ; 37(2): 415-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21241929

RESUMEN

We present an interventional case report of a 76-year-old man who developed bilateral angle-closure glaucoma with extensive choroidal detachment following administration of oral acetazolamide immediately after routine cataract extraction and intraocular lens implantation. Rapid clinical improvement occurred after acetazolamide was stopped and high-dose intravenous steroid therapy was given. Although extremely rare, this adverse effect should be considered in patients who develop acute bilateral angle-closure glaucoma and choroidal effusion after cataract surgery.


Asunto(s)
Acetazolamida/efectos adversos , Inhibidores de Anhidrasa Carbónica/efectos adversos , Extracción de Catarata , Enfermedades de la Coroides/inducido químicamente , Glaucoma de Ángulo Cerrado/inducido químicamente , Acetazolamida/administración & dosificación , Acetazolamida/uso terapéutico , Enfermedad Aguda , Administración Oral , Anciano , Inhibidores de Anhidrasa Carbónica/administración & dosificación , Inhibidores de Anhidrasa Carbónica/uso terapéutico , Enfermedades de la Coroides/diagnóstico , Fondo de Ojo , Glucocorticoides/administración & dosificación , Humanos , Inyecciones Intravenosas , Implantación de Lentes Intraoculares , Masculino , Metilprednisolona/administración & dosificación , Cuidados Posoperatorios , Ultrasonografía
7.
Eur J Ophthalmol ; 21(3): 251-7, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20853257

RESUMEN

PURPOSE: The aim of this study was to evaluate the measurement of intraocular pressure (IOP) using a new induction/impact rebound tonometer (ICare®) compared with Goldmann applanation tonometry (GAT). We also aimed to quantify the systematic and random errors (bias) of the 2 methods, to evaluate the sensitivity and specificity of the ICare® tonometer in identifying patients with 21 mmHg or more measured with the GAT, and to study the influence of corneal thickness on IOP measurement with the 2 tonometers. METHODS: We compared the IOP values obtained with the 2 instruments in 97 patients. RESULTS: Analysis based on the Bland and Altman method revealed that the IOP values recorded with the ICare® tonometer were slightly higher than those obtained with the GAT. The estimated bias for right eye measurements was 0.78 mmHg with 95% limits of agreement ±3.55 mmHg. This overestimation, which is not clinically relevant, was confirmed when we used the IOP values corrected according to central corneal thickness for data analysis. The sensitivity and specificity were 0.90 and 0.95, respectively. CONCLUSIONS: The ICare® tonometer proved to be comparable with other nonconventional tonometers and can be used by nonophthalmologists and paramedical personnel during screening tests of populations. In addition, the ICare® tonometer could be considered a valid alternative to GAT when GAT is not available.


Asunto(s)
Glaucoma/diagnóstico , Presión Intraocular/fisiología , Tonometría Ocular/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hipertensión Ocular/diagnóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Childs Nerv Syst ; 26(9): 1139-49, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20349187

RESUMEN

BACKGROUND: The incidence of preterm delivery and the survival rate of preterm newborns are rising, due to the increased use of assisted reproductive technology associated with multiple gestations and improved technology in obstetrics and neonatology, which allow saving preterm infants at earlier gestational ages. As a consequence, the risk of developmental disabilities in preterm children is high, and clinical pictures need to be fully defined. METHODS: Narrative review including articles regarding neurodevelopmental disorders published in the international medical literature and reported in PubMed between the years 2000 and January 2010. RESULTS: Although survival rates of extremely low birth weight infants (ELBW) significantly increased during the last decade, the substantial stability of disability trends in this population was disappointing. Late-preterm infants, who account for about 75% of all preterm births and had not been considered at risk for adverse long-term neurodevelopmental outcomes in the past, are now reconsidered as more likely to develop such events, though their risk remains lower than in ELBW. CONCLUSIONS: The findings of the studies discussed in our article support the importance of early diagnosis in order to make decision about appropriate treatment of preterm infants.


Asunto(s)
Trastornos del Conocimiento/fisiopatología , Discapacidades del Desarrollo/fisiopatología , Enfermedades del Prematuro/fisiopatología , Recien Nacido Prematuro , Trastornos del Conocimiento/patología , Discapacidades del Desarrollo/patología , Humanos , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recién Nacido , Enfermedades del Prematuro/patología , Nacimiento Prematuro
9.
Eur J Ophthalmol ; 20(1): 237-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19882512

RESUMEN

PURPOSE: We report a case of ocular worm treated surgically and confirmed by microbiological identification. METHODS: A 33-year-old Swiss woman presented to the ophthalmic unit, complaining of pain and foreign body sensation in the left eye. Slit-lamp examination disclosed a subconjunctival amber -colored cord in the conjunctival fornix. Presentation, clinical and histopathologic evaluation, and treatment are described. RESULTS: At the time of surgery, an alive and still intact worm was extracted through conjunctival incision. Histopathology confirmed the presence of filariasis. CONCLUSIONS: As the flow of immigrants from endemic areas of Europe increases, ocular manifestation of loiasis is becoming more frequent and ophthalmologists need to be aware of this diagnosis.


Asunto(s)
Enfermedades de la Conjuntiva/parasitología , Cuerpos Extraños en el Ojo/parasitología , Infecciones Parasitarias del Ojo/parasitología , Loa/aislamiento & purificación , Loiasis/parasitología , Adulto , Animales , Enfermedades de la Conjuntiva/diagnóstico , Enfermedades de la Conjuntiva/cirugía , Cuerpos Extraños en el Ojo/diagnóstico , Cuerpos Extraños en el Ojo/cirugía , Infecciones Parasitarias del Ojo/diagnóstico , Infecciones Parasitarias del Ojo/cirugía , Femenino , Humanos , Loiasis/diagnóstico , Loiasis/cirugía
10.
Radiology ; 252(2): 496-501, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19435941

RESUMEN

PURPOSE: To evaluate, with high-field-strength diffusion-tensor (DT) magnetic resonance (MR) imaging, the axonal architecture of the optic nerves and optic radiations in patients with glaucoma and determine whether DT MR imaging-derived parameters correlate with disease severity. MATERIALS AND METHODS: The study was approved by the institutional review board. All participants provided written informed consent. Sixteen patients with primary open-angle glaucoma were examined. Glaucoma severity was clinically assessed with use of a six-stage system based on static threshold visual field parameters. Ten healthy individuals served as control subjects. DT MR imaging was performed with a 3-T MR unit. Mean diffusivity (MD) and fractional anisotropy (FA) maps were automatically created. Regions of interest were positioned on the MD and FA maps, and mean MD and mean FA values were calculated for each optic nerve and each optic radiation. RESULTS: The optic radiations and optic nerves of patients with glaucoma, as compared with control subjects, had significantly higher MD and significantly lower FA. The mean MD values for the optic nerves and the glaucoma stages varied consistently (r = 0.8087, P < .0001). A negative correlation between mean FA for the optic nerves and glaucoma stage (r = -0.7464, P < .0001) was observed. CONCLUSION: Glaucoma is a complex neurologic disease that affects optic nerves and optic radiations. The finding that DT MR imaging-derived MD and FA in the optic nerves correlate with glaucoma severity suggests that these parameters could serve as complementary indicators of disease severity.


Asunto(s)
Vías Aferentes/patología , Glaucoma/complicaciones , Glaucoma/patología , Enfermedades del Nervio Óptico/complicaciones , Enfermedades del Nervio Óptico/patología , Nervio Óptico/patología , Anciano , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
Ophthalmic Epidemiol ; 15(6): 366-71, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19065429

RESUMEN

PURPOSE: To investigate the incidence of endophthalmitis in Italy. METHODS: The Ministry of Health Hospital Admissions online database was searched to identify cases of endophthalmitis and cases with risk factors for endophthalmitis (corneal ulcer, open wound of the eyeball, and intraocular surgery including retinal, iris, and lens procedures with or without vitrectomy). Annual Incidence rates (overall, and age- and gender-specific) were computed in the general population and in the population with one or more of the risk factors for endophthalmitis. RESULTS: The overall annual incidence of endophthalmitis / 100,000 inhabitants was 2.0 (95% confidence interval (CI):1.8-2.1) in 2003. The risk for endophthalmitis and for most factors that cause predisposition to endophthalmitis was higher in males. The annual incidence rates of corneal ulcer, open wounds of the eyeball, retinal procedures, iris procedures, lens procedures, and other intraocular procedures were respectively (per 100,000 inhabitants) 4.6, 4.8, 43.0, 9.2, 775.7, and 63.0. The annual incidence of endophthalmitis per 100,000 predisposed subjects was 220 (95% CI: 210-230), and the risk was higher in males (relative risk 1.7, 95% CI: 1.5-1.9). Annual incidence rates remained stable from 1999 to 2003. CONCLUSIONS: Higher rates of open wounds of the eyeball, corneal ulcers, and retinal surgery among males may be responsible for their higher risk for endophthalmitis.


Asunto(s)
Endoftalmitis/epidemiología , Vigilancia de la Población , Adolescente , Adulto , Distribución por Edad , Anciano , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Italia/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Distribución por Sexo , Adulto Joven
12.
Prog Brain Res ; 173: 3-14, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18929097

RESUMEN

Certain general conclusions can be drawn from a series of 56 studies on glaucoma prevalence. Even in the most recently published studies the rate of undiagnosed glaucoma is particularly high. Another fairly constant finding is the discrepancy between the clinical and epidemiologic diagnoses of glaucoma. The prevalence of primary open-angle glaucoma (POAG) has been increasing, and this trend is undoubtedly due at least in part to advances in diagnostic technology. The decreasing prevalence of primary angle-closure glaucoma (PACG) is due to the adoption of more stringent criteria for the diagnosis of this form of glaucoma. Prevalence increases proportionately with age for each racial group. African or African origin populations had the highest POAG prevalence at all ages but the increase in prevalence of POAG is steeper for white populations. PACG is commonest in Asian ethnic groups, with the exception of the Japanese. Low-tension glaucoma (LTG) is quite common in the Japanese population. Over 80% of those with PACG live in Asia, while POAG disproportionately affects those of African derivation. Women are more affected by glaucoma. Very few incidence studies have been completed, because the cost of examining large samples is high. There are only two recent studies conducted on persons of African descent in Barbados (West Indies) and on white inhabitants of Rotterdam (Netherlands). Risk of incident glaucoma was highest among persons classified as having suspect POAG at baseline, followed by those with ocular hypertension. No difference in incidence of POAG between men and women was found. The more recent studies which included routine visual-field testing reveal rates of blinding glaucoma <10% in many countries, including those that are developing.


Asunto(s)
Ceguera , Glaucoma de Ángulo Abierto/complicaciones , Glaucoma de Ángulo Abierto/epidemiología , Ceguera/epidemiología , Ceguera/etiología , Glaucoma de Ángulo Abierto/diagnóstico , Glaucoma de Ángulo Abierto/fisiopatología , Humanos , Factores de Riesgo
13.
Prog Brain Res ; 173: 575-82, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18929135

RESUMEN

Glaucoma is a worldwide leading cause of irreversible vision loss characterized by progressive death of retinal ganglion cells (RGCs). In the course of glaucoma, RGC death may be the consequence of energy impairment that triggers secondary excitotoxicity and free radical generation. There is substantial evidence also that a number of free radical scavengers and/or agents that improve mitochondrial function may be useful as therapies to ameliorate cell death in various neurological disorders including glaucoma. Coenzyme Q10 (CoQ10), an essential cofactor of the electron transport chain, has been reported to afford neuroprotection in neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases, and its protective effect has been attributed in part to its free radical scavenger ability and to a specific regulation of the mitochondrial permeability transition pore. Using an established animal model of transient retinal ischemia, we have conclusively identified a role for abnormal elevation of extracellular glutamate in the mechanisms underlying RGC death that occurs, at least in part, via activation of the apoptotic program. Under these experimental conditions, N-methyl-D-aspartate (NMDA) and non-NMDA subtype of glutamate receptor antagonists, nitric oxide synthase inhibitors, and CoQ10 afford retinal protection supporting an important role for excitotoxicity in the mechanisms underlying RGC death.


Asunto(s)
Glaucoma/tratamiento farmacológico , Fármacos Neuroprotectores , Retina/efectos de los fármacos , Ubiquinona/análogos & derivados , Animales , Calpaína/metabolismo , Muerte Celular/fisiología , Glaucoma/patología , Ácido Glutámico/metabolismo , Humanos , Presión Intraocular/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Estrés Oxidativo , Ratas , Daño por Reperfusión/prevención & control , Retina/citología , Retina/patología , Células Ganglionares de la Retina/metabolismo , Células Ganglionares de la Retina/patología , Ubiquinona/farmacología , Ubiquinona/uso terapéutico
14.
Int Rev Neurobiol ; 82: 397-406, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17678974

RESUMEN

Recent studies support a role for excitotoxicity in the development of retinal ganglion cell (RGC) damage in subjects suffering from glaucoma. Coenzyme Q10 (CoQ10), an essential cofactor of the electron transport chain, has been reported to afford neuroprotection, preventing the formation of the mitochondrial permeability transition pore. Using an established animal model of retinal ischemia/reperfusion here, we show that synaptic glutamate increases at 130min from beginning of reperfusion and delayed apoptosis in the RGC layer is seen at 24h. Intraocular administration of CoQ10 minimizes glutamate increase and affords neuroprotection, suggesting that oxidative stress and energy failure might be implicated in the mechanisms of RGC death.


Asunto(s)
Presión Intraocular/fisiología , Isquemia/patología , Enfermedades de la Retina/prevención & control , Ubiquinona/análogos & derivados , Administración Tópica , Animales , Coenzimas/administración & dosificación , Coenzimas/uso terapéutico , Ácido Glutámico/toxicidad , Etiquetado Corte-Fin in Situ , Masculino , Microdiálisis , Ratas , Ratas Wistar , Enfermedades de la Retina/patología , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología , Ubiquinona/administración & dosificación , Ubiquinona/uso terapéutico
15.
Invest Ophthalmol Vis Sci ; 48(7): 2997-3004, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17591864

RESUMEN

PURPOSE: To evaluate whether high intraocular pressure (IOP)-induced ischemia is associated with modifications in the retinal endocannabinoid metabolism and to ascertain whether drugs that interfere with the endocannabinoid system may prevent retinal damage due to ischemic insult. METHODS: Anandamide (AEA) synthesis, transport, hydrolysis, and AEA endogenous levels were assessed by means of high-performance liquid chromatography in the retinas of rats undergoing 45 minutes of ischemia followed by 12 hours of reperfusion. Under these experimental conditions, binding to cannabinoid (CB1R) and vanilloid (TRPV1) receptor was assessed with rapid-filtration assays. AEA-hydrolase (FAAH, fatty acid amide hydrolase), CB1R and TRPV1 protein content was determined by enzyme-linked immunosorbent assay. Finally, to characterize the neuroprotective profile of drugs that interfere with the endocannabinoid system, cell counting in the retinal ganglion cell (RGC) layer and real-time polymerase chain reactions for Thy-1 mRNA expression were used. RESULTS: In rat retina, ischemic insult followed by reperfusion resulted in enhanced FAAH activity and protein expression paralleled by a significant decrease in the endogenous AEA tone, whereas the AEA-membrane transporter or the AEA-synthase NAPE-PLD (N-acyl-phosphatidylethanolamine-hydrolyzing-phospholipase-d) were not affected. Retinal ischemia-reperfusion decreased the expression of cannabinoid (CB1) and vanilloid (TRPV1) receptors. Systemic administration of a specific FAAH inhibitor (e.g., URB597) reduced enzyme activity and minimized the retinal damage observed in ischemic-reperfused samples. Similarly, intravitreal injection of the AEA stable analogue, R(+)-methanandamide, reduced cell loss in the RGC layer, and this was prevented by systemic administration of a CB1 or TRPV1 selective antagonist (e.g., SR141716 and capsazepine, respectively). CONCLUSIONS: The original observation that retinal ischemia-reperfusion reduces endogenous AEA via enhanced expression of FAAH supports the deduction that this is implicated in retinal cell loss caused by high IOP in the RGC layer.


Asunto(s)
Moduladores de Receptores de Cannabinoides/fisiología , Endocannabinoides , Presión Intraocular , Daño por Reperfusión/metabolismo , Enfermedades de la Retina/metabolismo , Amidohidrolasas/antagonistas & inhibidores , Amidohidrolasas/metabolismo , Animales , Ácidos Araquidónicos/metabolismo , Benzamidas/farmacología , Capsaicina/análogos & derivados , Capsaicina/farmacología , Carbamatos/farmacología , Recuento de Células , Cromatografía Líquida de Alta Presión , Inhibidores Enzimáticos/farmacología , Ensayo de Inmunoadsorción Enzimática , Hidrólisis , Masculino , Hipertensión Ocular/complicaciones , Piperidinas/farmacología , Alcamidas Poliinsaturadas/metabolismo , Pirazoles/farmacología , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor Cannabinoide CB1/antagonistas & inhibidores , Receptor Cannabinoide CB1/metabolismo , Daño por Reperfusión/etiología , Daño por Reperfusión/patología , Daño por Reperfusión/prevención & control , Enfermedades de la Retina/etiología , Enfermedades de la Retina/patología , Enfermedades de la Retina/prevención & control , Células Ganglionares de la Retina/patología , Vasos Retinianos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rimonabant , Canales Catiónicos TRPV/antagonistas & inhibidores , Canales Catiónicos TRPV/metabolismo , Antígenos Thy-1/genética
16.
Acta Ophthalmol Scand ; 82(6): 718-22, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15606470

RESUMEN

PURPOSE: To determine whether implantation of a new intraocular lens (IOL) with a modified prolate anterior surface, designed to reduce the positive spherical aberration of the pseudophakic eyes, results in improved contrast sensitivity assessed in terms of low contrast visual acuity (VA). METHODS: We carried out an intraindividual study of 12 patients with bilateral cataracts, randomized to receive a prolate anterior surface IOL (Tecnis Z9000, Pharmacia) in one eye and a biconvex spherical surface IOL (CeeOn 911 A, Pharmacia) in the other. High and low contrast VA was assessed under photopic conditions, before and after pupil dilation. RESULTS: After mydriasis, the Technis Z9000 provided significantly better low contrast VA at contrast levels < or = 25%. No significant difference was found under normal pupil conditions. CONCLUSION: Our results confirm the hypothesis that the spherical aberration of the eye after cataract surgery can be reduced by an anterior prolate surface IOL.


Asunto(s)
Sensibilidad de Contraste/fisiología , Implantación de Lentes Intraoculares , Lentes Intraoculares , Seudofaquia/fisiopatología , Agudeza Visual/fisiología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Facoemulsificación , Diseño de Prótesis
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