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El edema macular pseudofáquico (EMP) es una complicación en la cirugía de catarata. Existen diversos factores que aumentan el riesgo de desarrollar EMP tales como la uveítis, membranas epirretinianas y diabetes mellitus. Se ha demostrado ampliamente que un mayor porcentaje de pacientes diabéticos desarrolla EMP tras someterse a cirugía de catarata frente a los pacientes no diabéticos. El EM es la principal causa de pérdida de agudeza visual en estos pacientes. Existen dos tipos de EM en paciente diabético: 1) El EMP tras cirugía de catarata en pacientes diabéticos. 2) El Edema macular diabético (EMD)que se genera por las alteraciones intrínsecas vasculares que el paciente diabético tiene. Un tratamiento preventivo podría mejorar los resultados de los pacientes diabéticos tras someterse a cirugía de catarata, con los correspondientes beneficios para la calidad de vida del paciente y su repercusión en los costes sanitarios asociados a esta patología. Existen 4 AINEs aprobados por la FDA (Food and Drugs Administration) para el manejo de la inflamación tras la cirugía de catarata: bromfenaco, dicloflenaco, ketorolaco y nepafenaco. Aunque prácticamente todos los AINEs se han venido usando en prevención en pacientes intervenidos quirúrgicamente de catarata, nepafenaco es el único aprobado por la EMA (European Medicines Agency) para esta indicación, y lo ha demostrado en pacientes con retinopatía diabética. El objetivo del presente trabajo es revisar la literatura publicada al respecto y destacarla importancia de una estrategia de prevención de edema macular en pacientes diabéticos sometidos a cirugía de catarata (AU)

Pseudophakic macular edema (PME) is a common complication of cataract surgery. There are several factors that increase the risk of developing PME such as uveitis, epiretinal membranes and diabetes mellitus. There is ample evidence that a higher percentage of diabetic patients develop PME after undergoing cataract surgery compared to patients without diabetes.Macular edema is the main cause of loss of visual acuity in these patients. There are two types of ME in diabetic patients: 1) PME after cataract surgery in diabetic patients. 2) Diabetic Macular Edema (DME) that is generated by intrinsic vascular alterations present in diabetic patients. A preventive treatment could improve outcomes of diabetic patients undergoing cataract surgery, with corresponding benefits to the quality of life and their impact on health care costs associated with this pathology. There are 4 NSAIDs approved by the FDA (Food and Drugs Administration) for the management of inflammation after cataract surgery: bromfenac, dicloflenac, ketorolac and nepafenaco. Although practically all NSAIDs are been used for the prevention in patients with cataract surgery, nepafenac is the only one approved by the EMA (European Medicines Agency) for this indication, and it has demonstrated its effects in patients with diabetic retinopathy. The aim of this paper is to review the published literature and highlight the importance of a macular edema prevention strategy in diabetic patients undergoing cataract surgery (AU)

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OBJECTIVE: To assess the mean best-corrected visual acuity (BCVA) change in patients with exudative-haemorrhagic age-related macular degeneration (EH-ARMD) after 12-month period of treatment with ranibizumab. METHODS: A retrospective, multicentre and national study of intravitreal administered ranibizumab was conducted on 2 groups of EH-ARMD patients: only one eye affected (group 1) versus second eye affected (group 2), having the first one affected. Eligible subjects were ≥ 50 years old with primary or secondary active subfoveal EH-ARMD-related choroidal neovascularisation (CNV). RESULTS: A total of 184 patients (91 group 1 and 93 group 2) were included. Mean age (SD) was 75.3 (7.5) years, and 53.6% were women. The BCVA showed a VA improvement at 12 months of 9.3 (18.0) number of letters in group 1 and 5.1 (16.8) number of letters in group 2 (P<.0001 and P=.0042, respectively). No statistical differences between groups were observed. Lesion characteristics in the total population (baseline vs 12-month) were: drusen (69.1% vs 61.1%), macular haemorrhages (59.0% vs 7.3%), lipid exudates (28.1% vs 8.2%), and retinal pigment epithelium detachment (46.8% vs 19.0%). The optical coherence tomography (OCT) in the total population (baseline vs 12-month) showed a reduction in macular oedema (73.6% vs 20.9%), subretinal fluids (71.3% vs 14.7%), and intraretinal cysts (38.5 vs 19.7%), as well as a reduction of the mean foveal thickness 377.4 ± 109.8µm vs 249.1 ± 67.8µm in group 1 and 354.1 ± 123.2µm vs 254.6 ± 67.4µm in group 2, P<.0001, both groups, with no significant differences between groups. CONCLUSIONS: Intravitreal administration of ranibizumab for a minimum of 12-months significantly improved the BCVA, decreased lesion characteristics, and reduced the initial mean foveal thickness in patients with CNV primary or secondary to EH-ARMD, both in patients with only one eye affected and in patients with a second eye affected, having the first one affected.

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Objetivo: Evaluar el cambio medio de la mejor agudeza visual corregida (MAVC) en pacientes con degeneración macular asociada a la edad exudativa-hemorrágica (DMAE-EH) a los 12 meses de tratamiento con ranibizumab. Métodos: Estudio observacional, retrospectivo, multicéntrico y nacional, en dos grupos de pacientes con DMAE-EH: primer ojo afectado (grupo 1) y segundo ojo afectado (grupo 2), teniendo afectado el primer ojo. Se incluyeron pacientes ≥ 50 años, diagnosticados de neovascularización coroidea subfoveal activa principal o recurrente secundaria a DMAE-EH. Resultados: Se incluyó a 184 pacientes (91 en grupo 1 y 93 en grupo 2), edad media ± DE de 75,3 ± 7,5 años y 53,6% mujeres. La MAVC mostró una mejoría de la AV a los 12 meses de 9,3 ± 18,0 número de letras en el grupo 1 y 5,1 ± 16,8 número de letras en el grupo 2 (p < 0,0001 y p = 0,0042, respectivamente), sin observarse diferencias significativas (NS) entre ambos grupos. Las lesiones retinianas en la población total (basal vs 12 meses) fueron: drusas (69,1 vs 61,1%), hemorragias maculares (59,0 vs 7,3%), exudados lipídicos (28,1 vs 8,2%) y desprendimiento del epitelio pigmentario (46,8 vs 19,0%). Los resultados de la tomografía de coherencia óptica (OCT) en la población total (basal vs 12 meses) mostraron una reducción del edema macular (73,6 vs 20,9%), del fluido subretiniano (71,3 vs 14,7%) y de quistes intrarretinianos (38,5 vs 19,7%), así como una reducción del grosor foveal medio de 377,4 ± 109,8 μm vs 249,1 ± 67,8 μm en el grupo 1 y de 354,1 ± 123,2 μm vs 254,6 ± 67,4 μm en el grupo 2, con p < 0,0001 en ambos grupos, sin observarse diferencias significativas entre grupos (AU)

Conclusiones: La administración de ranibizumab intravítreo durante un mínimo de 12 meses conllevó una mejoría significativa en la MAVC, una disminución de las lesiones retinianas y una disminución del grosor retiniano medio inicial en pacientes con NVC principal o secundaria a DMAE-EH, tanto en los pacientes con primer ojo afectado como en los pacientes con segundo ojo afectado, teniendo afectado el primero (AU)

Objective: To assess the mean best-corrected visual acuity (BCVA) change in patients with exudative-haemorrhagic age-related macular degeneration (EH-ARMD) after 12-month period of treatment with ranibizumab. Methods: A retrospective, multicentre and national study of intravitreal administered ranibizumab was conducted on 2 groups of EH-ARMD patients: only one eye affected (group 1) versus second eye affected (group 2), having the first one affected. Eligible subjects were ≥ 50 years old with primary or secondary active subfoveal EH-ARMD-related choroidal neovascularisation (CNV). Results: A total of 184 patients (91 group 1 and 93 group 2) were included. Mean age (SD) was 75.3 (7.5) years, and 53.6% were women. The BCVA showed a VA improvement at 12 months of 9.3 (18.0) number of letters in group 1 and 5.1 (16.8) number of letters in group 2 (P<0.0001 and P=0.0042, respectively). No statistical differences between groups were observed. Lesion characteristics in the total population (baseline vs 12-month) were: drusen (69.1% vs 61.1%), macular haemorrhages (59.0% vs 7.3%), lipid exudates (28.1% vs 8.2%), and retinal pigment epithelium detachment (46.8% vs 19.0%). The optical coherence tomography (OCT) in the total population (baseline vs 12-month) showed a reduction in macular oedema (73.6% vs 20.9%), subretinal fluids (71.3% vs 14.7%), and intraretinal cysts (38.5 vs 19.7%), as well as a reduction of the mean foveal thickness 377.4 ± 109.8 μm vs 249.1 ± 67.8 μm in group 1 and 354.1 ± 123.2 μm vs 254.6 ± 67.4 μm in group 2, P<0.0001, both groups, with no significant differences between groups. Conclusions: Intravitreal administration of ranibizumab for a minimum of 12-months significantly improved the BCVA, decreased lesion characteristics, and reduced the initial mean foveal thickness in patients with CNV primary or secondary to EH-ARMD, both in patients with only one eye affected and in patients with a second eye affected, having the first one affected (AU)

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Objetivo: Describir los resultados clínicos de la cirugía combinada de catarata (facoemulsificación e implante de lente intraocular) y vitrectomía 23-gauge, y evaluar la eficacia y la seguridad de esta técnica. Métodos: Estudio retrospectivo, consecutivo y no comparativo. Se incluyeron 105 ojos a los que se realizó cirugía combinada de catarata (facoemulsificación e implante de lente intraocular en el saco capsular) y vitrectomía 23-gauge por diversas indicaciones. Se midió la mejor agudeza visual corregida (AV logMAR) y la presión intraocular (PIO) previa y posteriormente a la cirugía, y se registraron las complicaciones postoperatorias. Resultados: El periodo de seguimiento posquirúrgico medio fue de 16,6±9,9 meses. La media de la AV logMAR preoperatoria fue 0,83±0,4 y la postoperatoria 0,44±0,38 en la visita final (1 mes), con una mejoría en el 83% de los ojos. La PIO media preoperatoria fue 16,7±3,7mmHg. En el postoperatorio, la PIO media fue 22,5±12,8 el primer día, 17,5±6,8 tras una semana y 15,3±3,8mmHg al mes. Las complicaciones postoperatorias incluyeron: opacificación capsular posterior (n=5), edema macular (n=4), desepitelización corneal (n=3), desprendimiento de retina (n=2), vitreorretinopatía proliferativa (n=2), desprendimiento coroideo (n=1), agujero macular (n=1), hemorragia vítrea (n=1) y membrana epirretiniana (n=1). Conclusiones: Los resultados obtenidos en este estudio demuestran que la cirugía combinada de catarata con vitrectomía 23-gauge es una técnica segura y eficaz. Entre otras ventajas ofrece una rápida rehabilitación, una escasa incidencia de complicaciones y evita una nueva intervención(AU)

Purpose: To report the clinical outcomes of cataract surgery (phacoemulsification and intraocular lens implantation) combined with 23-gauge vitrectomy, and to evaluate the effectiveness and safety of this technique. Methods: A retrospective, consecutive, non-comparative study which included 105 eyes. Phacoemulsification and intraocular lens implantation (in the capsular sac) combined with 23-gauge vitrectomy were performed. Indications for undergoing surgery were varied. Best corrected logMAR visual acuity (VA) and intraocular pressure (IOP) were measured pre- and postoperatively, and postoperative complications were recorded. Results: Patients were followed-up for a mean of 16.6±9.9 months. The mean preoperative VA was 0.83±0.40 logMAR, and mean postoperative VA one month after surgery was 0.44±0.38 logMAR. The postoperative visual acuity improved in 83.8% of cases. The mean preoperative IOP was 16.6±3.7mmHg, while the mean postoperative IOP was 22.5±12.8mmHg (1 day after surgery), 17.5±6.8mmHg (after 1 week), and 15.3±3.8mmHg (after 1 month). Postoperative complications included posterior capsular opacification (n=5), macular edema (n=4), corneal de-epithelization (n=3), retinal detachment (n=2), proliferative vitreoretinopathy (n=2), choroidal detachment (n=1), macular hole (n=1), vitreous hemorrhage (n=1), epiretinal membrane (n=1), and transient elevated intraocular pressure (n=36). Conclusions: The surgery reported in this study involving phacoemulsification combined with 23-gauge vitrectomy was found to be safe and effective, and was associated with improved clinical features, including rapid rehabilitation, a low incidence of complications, and avoids repeat surgery(AU)

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PURPOSE: To report the clinical outcomes of cataract surgery (phacoemulsification and intraocular lens implantation) combined with 23-gauge vitrectomy, and to evaluate the effectiveness and safety of this technique. METHODS: A retrospective, consecutive, non-comparative study which included 105 eyes. Phacoemulsification and intraocular lens implantation (in the capsular sac) combined with 23-gauge vitrectomy were performed. Indications for undergoing surgery were varied. Best corrected logMAR visual acuity (VA) and intraocular pressure (IOP) were measured pre- and postoperatively, and postoperative complications were recorded. RESULTS: Patients were followed-up for a mean of 16.6±9.9 months. The mean preoperative VA was 0.83±0.40 logMAR, and mean postoperative VA one month after surgery was 0.44±0.38 logMAR. The postoperative visual acuity improved in 83.8% of cases. The mean preoperative IOP was 16.6±3.7mmHg, while the mean postoperative IOP was 22.5±12.8mmHg (1 day after surgery), 17.5±6.8mmHg (after 1 week), and 15.3±3.8mmHg (after 1 month). Postoperative complications included posterior capsular opacification (n=5), macular edema (n=4), corneal de-epithelization (n=3), retinal detachment (n=2), proliferative vitreoretinopathy (n=2), choroidal detachment (n=1), macular hole (n=1), vitreous hemorrhage (n=1), epiretinal membrane (n=1), and transient elevated intraocular pressure (n=36). CONCLUSIONS: The surgery reported in this study involving phacoemulsification combined with 23-gauge vitrectomy was found to be safe and effective, and was associated with improved clinical features, including rapid rehabilitation, a low incidence of complications, and avoids repeat surgery.

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The Spanish Quality Assurance Program applied to the process of donation after brain death entails an internal stage consisting of a continuous clinical chart review of deaths in critical care units (CCUs) performed by transplant coordinators and periodical external audits to selected centers. This paper describes the methodology and provides the most relevant results of this program, with information analyzed from 206,345 CCU deaths. According to the internal audit, 2.3% of hospital deaths and 12.4% of CCU deaths in Spain yield potential donors (clinical criteria consistent with brain death). Out of the potential donors, 54.6% become actual donors, 26% are lost due to medical unsuitability, 13.3% due to refusals to donation, 3.1% due to maintenance problems and 3% due to other reasons. Although the national pool of potential donors after brain death has progressively decreased from 65.2 per million population (pmp) in 2001 to 49 pmp in 2010, the number of actual donors after brain death has remained at about 30 pmp. External audits reveal that the number of actual donors could be 21.6% higher if all potential donors were identified and preventable losses avoided. We encourage other countries to develop similar comprehensive approaches to deceased donation performance.

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PURPOSE: The retina is the neurosensorial tissue of the eye and is extremely rich in polyunsaturated lipid membranes. This feature makes it especially sensitive to oxygen and/or nitrogen activated species and lipid peroxidation. Several authors have postulated the importance of superoxide (O2-) and peroxynitrite production in the development of diabetic complications. In the present study, we have used two different antioxidants, ebselen and lutein, that present as a common feature their peroxynitrite scavenging capacity, to ameliorate the oxidative stress that exists in the retina in diabetic patients. METHODS: Hyperglycemia was accomplished by the intraperitoneal injection of Alloxan in a mouse model of diabetic retinopathy. Malondialdehyde (MDA) and glutathione (GSH) concentrations in eye homogenates (without the lens) were determined. We also recorded serial electroretinograms (ERG) and measured latency and implicit times. RESULTS: The MDA concentration increased and the GSH concentration decreased in the eyes of the diabetic animals. Treatment with ebselen and lutein restored the MDA and GSH concentrations to control values. Latency and implicit times were not affected by the diabetes. CONCLUSION: New studies are required to better understand the protective mechanism of ebselen and lutein in this model of experimental diabetic retinopathy.

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Propósito: La retina es el tejido neurosensorial del ojo y es extremadamente rica en membranas con lípidos poliinsaturados. Esta característica la hace especialmente sensible a los radicales libres derivados de oxígeno o nitrógeno y a la peroxidación lipídica. Diversos autores postulan la importancia de la producción de superóxido (O2– ) y peroxinitrito en el desarrollo de las complicaciones de la diabetes. En este trabajo hemos empleado dos antioxidantes, ebselen y luteína, que presentan la característica común de ser secuestrantes de peroxinitrito, para evitar el estrés oxidativo que la hiperglucemia induce en la retina.Métodos: La hiperglucemia se consiguió mediante la inyección de Aloxana. Se determinaron la concentración de malondialdehído (MDA) y de glutation (GSH) en homogenado de ojo. También se realizaron electrorretinogramas (ERG) de todos los animales y se midió el tiempo de latencia y de culminación.Resultados: La concentración de MDA aumentó y la de GSH disminuyó en los animales diabéticos. Los tratamientos con ebselen y luteína corrigieron las concentraciones de MDA y de GSH. El tiempo de latencia y de culminación del ERG no se ve afectado por la diabetes.Conclusión: Se requieren nuevos estudios para confirmar el mecanismo protector del ebselén y la luteína en este modelo de diabetes experimental

Purpose: The retina is the neurosensorial tissue of the eye and is extremely rich in polyunsaturated lipid membranes. This feature makes it especially sensitive to oxygen and/or nitrogen activated species and lipid peroxidation. Several authors have postulated the importance of superoxide (O2– ) and peroxynitrite production in the development of diabetic complications. In the present study, we have used two different antioxidants, ebselen and lutein, that present as a common feature their peroxynitrite scavenging capacity, to ameliorate the oxidative stress that exists in the retina in diabetic patients. Methods: Hyperglycemia was accomplished by the intraperitoneal injection of Alloxan in a mouse model of diabetic retinopathy. Malondialdehyde (MDA) and glutathione (GSH) concentrations in eye homogenates (without the lens) were determined. We also recorded serial electroretinograms (ERG) and measured latency and implicit times. Results: The MDA concentration increased and the GSH concentration decreased in the eyes of the diabetic animals. Treatment with ebselen and lutein restored the MDA and GSH concentrations to control values. Latency and implicit times were not affected by the diabetes. Conclusion: New studies are required to better understand the protective mechanism of ebselen and lutein in this model of experimental diabetic retinopathy

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PURPOSE: To compare three methods of inducing experimental glaucoma in the adult pig, based on achieving chronic elevation of the intraocular pressure (IOP). METHODS: A total of 16 adult pigs were used in the present study. In all instances, the right eye was used as control and the left eye as the experimental eye. The animals were divided into three groups: 1) 3 pigs in which 3 episcleral veins were cauterized (experimental period = 21 weeks); 2) 6 animals in which the anterior chamber of the eye was injected with a solution containing latex fluorospheres (experimental period = 11 weeks); and 3) 4 pigs in which the anterior chamber of the eye was injected with a solution containing latex fluorospheres plus methylcellulose (experimental period = 11 weeks). RESULTS: The episcleral vein cauterization was the only method which produced a sustained elevation of the IOP throughout most of the experimental period. Moreover, the elevation of the IOP achieved by this method resulted in selective retinal ganglion cell (RGC) loss that affected mainly the mid-peripheral and peripheral retina and caused an increase in the mean soma area of the remaining RGCs. CONCLUSIONS: Cauterization of the episcleral veins resulted in a significant and sustained elevation of the IOP and RGC loss when compared with the other two approaches tested in the present study, which barely modified the pig's RGC distribution. Thus, we conclude that the episcleral vein cauterization is the best of the methods tested to induce experimental glaucoma in the pig.

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Objetivo: Comparar tres métodos de inducción de glaucoma experimental en el cerdo adulto, basados en el aumento crónico de la presión intraocular (PIO).Material y métodos: En el presente estudio se emplearon un total de 16 cerdos adultos. En todos los casos se utilizaron los ojos derechos como control y los ojos izquierdos fueron operados. Dividimos los animales en tres grupos: 1) tres cerdos a los que se les cauterizó tres de las venas epiesclerales (período de seguimiento = 21 semanas), 2) seis animales a los que se les inyectó una solución que contenía fluoroesferas en la cámara anterior (período de seguimiento = 11 semanas) y 3) cuatro cerdos a los que se les inyectó una solución que contenía fluoroesferas junto con metil-celulosa en la cámara anterior (período de seguimiento = 11 semanas).Resultados: La cauterización de las venas epiesclerales resultó ser el único de los métodos que produjo un aumento mantenido de la PIO a lo largo de la mayor parte del periodo experimental. Además, el aumento de la PIO producido siguiendo este método resultó en una pérdida selectiva de células ganglionares de la retina (CGR), la cual afectó principalmente a la retina media y periférica y causó un aumento en el área media de las CGR supervivientes.Conclusiones: La cauterización de las venas epiesclerales provocó un aumento mantenido y significativo de la PIO así como una pérdida de CGR, en comparación con los otros dos métodos utilizados en el presente estudio, los cuales apenas modificaron la distribución de las CGR de cerdo. Por tanto, concluimos que la cauterización de las venas epiesclerales es el mejor de los métodos ensayados para inducir glaucoma experimental en cerdo

Purpose: To compare three methods of inducing experimental glaucoma in the adult pig, based on achieving chronic elevation of the intraocular pressure (IOP). Methods: A total of 16 adult pigs were used in the present study. In all instances, the right eye was used as control and the left eye as the experimental eye. The animals were divided into three groups: 1) 3 pigs in which 3 episcleral veins were cauterized (experimental period = 21 weeks); 2) 6 animals in which the anterior chamber of the eye was injected with a solution containing latex fluorospheres (experimental period = 11 weeks); and 3) 4 pigs in which the anterior chamber of the eye was injected with a solution containing latex fluorospheres plus methylcellulose (experimental period = 11 weeks). Results: The episcleral vein cauterization was the only method which produced a sustained elevation of the IOP throughout most of the experimental period. Moreover, the elevation of the IOP achieved by this method resulted in selective retinal ganglion cell (RGC) loss that affected mainly the mid-peripheral and peripheral retina and caused an increase in the mean soma area of the remaining RGCs. Conclusions: Cauterization of the episcleral veins resulted in a significant and sustained elevation of the IOP and RGC loss when compared with the other two approaches tested in the present study, which barely modified the pig's RGC distribution. Thus, we conclude that the episcleral vein cauterization is the best of the methods tested to induce experimental glaucoma in the pig

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PURPOSE: Diabetic retinopathy is the primary cause of blindness in developed countries, and though strict glycemic control is desirable to prevent complications, this is not always achievable. Thus, adjunctive therapies are needed to help in preventing or delaying the onset of diabetic complications. We have studied the biochemical and functional changes in the retina of diabetic mice, and the ability of ebselen and lutein, two antioxidants, to reverse these effects, using as a comparison the effect of insulin therapy. METHODS: Alloxan injection was used to achieve hyperglycemia. Malondialdehyde (MDA) concentration in blood and glutathione peroxidase (GPx) activity in eye homogenate were measured. Serial electroretinograms (ERG) were recorded. RESULTS: MDA concentration in the blood was high in diabetic animals. GPx activity in eye homogenate decreased in the diabetic conditions. Maximal electroretinogram amplitude decreased in diabetic animals with respect to controls. Ebselen and lutein restored MDA levels, GPx activity and ERG amplitude, and had no effect on glycemia. CONCLUSION: These results call for further studies on ebselen or lutein as adequate adjunctive therapies for diabetes.

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Propósito: La retinopatía diabética es la primera causa de ceguera en países desarrollados, aunque lo mejor para prevenir las complicaciones es un adecuado control glucémico, este no siempre se puede conseguir. Por tanto, es necesario el uso de terapias coadyuvantes que ayuden a prevenir o retrasar la aparición de complicaciones propias de la diabetes. Se han estudiado los cambios bioquímicos y funcionales que ocurren en la retina de ratones diabéticos, y la capacidad del ebselen y la luteína, dos antioxidantes de corregir estos efectos, comparándolos con la terapia insulínica. Métodos: La hiperglucemia se consiguió mediante la inyección de Aloxana. Se determinaron la concentración sérica de Malondialdehído (MDA) y la actividad glutation peroxidasa (GPx) en homogenado de ojo. También se realizaron electroretinogramas (ERG) de todos los animales. Resultados: La concentración sérica de MDA aumentó y la actividad GPx disminuyó en los animales diabéticos. La amplitud máxima del electroretinograma disminuyó en los animales diabéticos con respecto a los controles. Los tratamientos con Ebselen y luteína corrigieron los valores de MDA, actividad GPx y amplitud en el ERG, sin tener ningún efecto sobre la glucemia. Conclusión: Estos resultados inducen nuevos estudios sobre el ebselen y la luteína como adecuadas terapias coadyuvantes en la diabetes(AU)

Purpose: Diabetic retinopathy is the primary cause of blindness in developed countries, and though strict glycemic control is desirable to prevent complications, this is not always achievable. Thus, adjunctive therapies are needed to help in preventing or delaying the onset of diabetic complications. We have studied the biochemical and functional changes in the retina of diabetic mice, and the ability of ebselen and lutein, two antioxidants, to reverse these effects, using as a comparison the effect of insulin therapy. Methods: Alloxan injection was used to achieve hyperglycemia. Malondialdehyde (MDA) concentration in blood and glutathione peroxidase (GPx) activity in eye homogenate were measured. Serial electroretinograms (ERG) were recorded. Results: MDA concentration in the blood was high in diabetic animals. GPx activity in eye homogenate decreased in the diabetic conditions. Maximal electroretinogram amplitude decreased in diabetic animals with respect to controls. Ebselen and lutein restored MDA levels, GPx activity and ERG amplitude, and had no effect on glycemia. Conclusion: These results call for further studies on ebselen or lutein as adequate adjunctive therapies for diabetes(AU)

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PURPOSE: To study the pig retinal ganglion cell (RGC) survival in culture, analysing the possible neuroprotective effect of retinal Müller glia (RMG) and brain-derived neurotrophic factor (BDNF). METHODS: Adult pig retina were dissociated and cultured under different conditions: 1) on laminin/poly-D-lysine-coated coverslips in chemically defined medium (CDM); 2) on laminin/poly-D-lysine-coated coverslips in CMD supplemented with BDNF; 3) on confluent monolayer cultures of RMG in CDM; 4) on laminin/poly-D-lysine substrate in conditioned medium obtained from RMG. RGCs were identified by immunocytochemistry using antibody against 68 kDa neurofilament and observed under an fluorescent microscope. RGCs were classified on the basis of the size, number and length of neurites, and their survival was assayed for each treatment. RESULTS: Confluent RMG substrates and RMG conditioned medium significantly increased the survival of cultured pig RGC. Moreover these two conditions increased the mean area of RGCs and enhanced neurite growth and elongation. Addition of BDNF to culture medium did not modify survival but increased RGC size, neurite number and neurite length. CONCLUSIONS: These findings demonstrate that factor(s) secreted by RMG exert beneficial effects on adult RGC survival and neurite regeneration in vitro, and might constitute important agent(s) for RGC neuroprotection. BDNF also increases the mean area of RGCs and enhances neurite growth but it does not increase the survival of RGCs.

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Objetivo: Estudiar la supervivencia de las células ganglionares de la retina (CGR) de cerdo en cultivo, analizando el posible efecto neuroprotector de las células de Müller de la retina (CMR) y del factor neurotrófico derivado del cerebro (BDNF).Métodos: Las retinas de cerdo adulto fueron disociadas y cultivadas en diferentes condiciones: 1) sobre sustrato de laminina/poli-D-lisina en medio de cultivo químicamente definido; 2) sobre sustrato de laminina/poli-D-lisina en medio químicamente definido al que se añadió BDNF; 3) sobre monocapas de CMR en medio químicamente definido; 4) sobre sustrato de laminina/poli-D-lisina en medio condicionado procedente del sobrenadante de las CMR. Las CGR fueron identificadas mediante inmunocitoquímica, utilizando anticuerpos contra el neurofilamento de 68 kDa, y observadas con un microscopio de fluorescencia. Se analizó la supervivencia para cada condición de cultivo y se clasificaron las CGR en función de su tamaño y del número y longitud de las neuritas. Resultados: La supervivencia de las CGR aumentó cuando las células fueron cultivadas sobre monocapas confluentes de CMR o en medio condicionado. Estas condiciones produjeron un incremento en el área media de las células y un aumento en el número de neuritas emitidas por cada célula, así como en la longitud de las neuritas. Cuando el medio de cultivo se suplementó con BDNF no se obtuvo ningún efecto sobre la supervivencia de las CGR aunque aumentó el tamaño, y el número y longitud de sus neuritas. Conclusión: Nuestro trabajo demuestra que algún/os factor/es secretados por las células de Müller tienen un efecto neuroprotector sobre las CGR in vitro. El BDNF produce también un incremento en el área media de las células y favorece la formación de neuritas, sin embargo no aumenta la supervivencia (AU)

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INTRODUCTION: The Real Ordinance 2070/1999 meant an important modification in the legislation, when including transcranial Doppler (TCD) in explorations to confirm the clinical diagnosis of brain death (BD). Habitually for their employment in the diagnosis of BD, we look for blood flow signal from the middle cerebral arteries (MCA) and the basilar artery (BA). OBJECTIVES: To check the effectiveness of the TCD like test of BD, looking for both middle cerebral arteries (MCA) and both intracranial vertebral arteries (VA), instead of the BA, and taking as Gold Standard cerebral scintigraphic techniques. PATIENTS AND METHODS: . We present 25 patients diagnosed clinically with BD; on these TCD was carried out to confirm BD. Later on we proceeded to carry out cerebral scintigraphic techniques in all these cases. As statistical tool the test of c2 is used with confidence interval of 95%. RESULTS: In 24 of the 25 cases, the TCD was effective in confirming the diagnosis of BD. In the remaining patient, a false positive result was obtained, since the TCD didn't reveal flow in the infratentorial compartment, as contrary to the cerebral scintigraphic techniques which showed the presence of residual flow at this level; this residual flow disappeared in 36 hours. This patient was hemodynamically unstable during TCD exploration. CONCLUSIONS: In our results the TCD obtains a reliability of 100% when confirming the absence of blood flow in the supratentorial compartment; nevertheless the false positive result obtained at the infratentorial level, warns us to be cautious in accepting the flow from the VA as a test of absence of flow at the infratentorial compartment, especially in those patients with hemodynamic instability.

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PURPOSE: To evaluate, in vitro, the solubility and stability of all-trans RA in silicone oil (SiO) and, in vivo, the stability and the antiproliferative effect of all-trans RA in SiO on an experimental model of PVR. METHODS: The solubility and stability of RA in SiO, in vitro and in vivo, were evaluated by HPLC. Rabbits underwent unilateral gas-compression vitrectomy and gas-SiO exchange. Rabbits received 10 micrograms (n = 17), 5 micrograms (n = 11), and 2 micrograms (n = 9) of all-trans RA in SiO, and SiO only (n = 12). All rabbits received an intravitreous injection of 150,000 fibroblasts. RESULTS: RA is stable in SiO in vitro, but some isomerization from all-trans to 13-cis was observed under light exposure. In vivo, after 1 week, trace amounts of RA in SiO were observed in the controls and in the experimental animals, suggesting a steady state between the release of RA from the SiO and from the retina to the SiO. The rate of fractional retinal detachment was significantly lower in the animals that received 10 and 5 micrograms of RA than in the controls (P < 0.05). No statistical differences were found between the eyes treated with 10 and 5 micrograms of RA. Eyes that received 2 micrograms of RA showed no difference from the control group. CONCLUSIONS: The in vivo data suggest that retinoic acid might be useful as an antiproliferative agent in human eyes.

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The antiproliferative properties of a single intravitreous injection of BCNU [carmustine; 1,3-bis(2 chloroethyl)-1-nitrosourea] dissolved in 1 ml of medical grade, 1,000-centistoke silicone oil were evaluated in a rabbit model of proliferative vitreoretinopathy (PVR). 10 micrograms and 15 micrograms of BCNU in 1 ml silicone oil resulted in a 46% and 27% reduction in the incidence of retinal detachments, respectively. Chi-square tests showed a significant statistical difference (P < 0.05) between the control and treated groups. However, histopathologic examination of the eyes injected with BCNU and silicone oil indicated some retinal disorganization even at the lower therapeutic levels. With a therapeutic index of < 1.0, BCNU in silicone oil has a low margin of safety for treatment of PVR. Nevertheless, this study demonstrates that silicone oil when used for retinal tamponade in PVR may be the vehicle for delivery of a lipophilic antiproliferative agent.

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