Experimental glaucoma triggers a pro-oxidative and pro-inflammatory state in the rat cornea.

BACKGROUND: Increasing evidence suggests that glaucoma affects the ocular surface. We aimed to investigate the cellular mechanisms underlying the glaucoma-associated corneal alterations in an animal model. METHODS: Wistar rats underwent the cauterization of two episcleral veins of the left eye to elevate the intraocular pressure (ipsilateral, G-IL). Control animals received a sham procedure (C-IL). Contralateral eyes did not receive any procedure (G-CL or C-CL). Enzymes related to the redox status, oxidative damage to macromolecules, and inflammatory markers were assessed in corneal lysates. RESULTS: Compared to C-IL, NOX4, NOX2, and iNOS expression was increased in G-IL (68%, p < 0.01; 247%, p < 0.01; and 200%, p < 0.001, respectively). We found an increase in SOD activity in G-IL (60%, p < 0.05). The GSH/GSSG ratio decreased in G-IL (80%, p < 0.05), with a decrease in GR activity (40%, p < 0.05). G-IL displayed oxidative (90%, p < 0.01) and nitrosative (40%, p < 0.05) protein damage, and enhanced lipid peroxidation (100%, p < 0.01). G-IL group showed an increased in CD45, CD68 and F4/80 expression (50%, p < 0.05; 190%, p < 0.001 and 110%, p < 0.05, respectively). G-CL displayed a higher expression of Nrf2 (60%, p < 0.001) and increased activity of SOD, CAT, and GPx (60%, p < 0.05; 90%, p < 0.01; and 50%, p < 0.05, respectively). CONCLUSIONS: Glaucoma induces a redox imbalance in the ipsilateral cornea with an adaptive response of the contralateral one. GENERAL SIGNIFICANCE: Our study provides a possible mechanism involving oxidative stress and inflammation that explains the corneal alterations observed in glaucoma. We demonstrate that these changes extend not only to the ipsilateral but also to the contralateral cornea.

Mitochondrial function is impaired in the primary visual cortex in an experimental glaucoma model.

Glaucoma is a neurodegenerative disease that affects eye structures and brain areas related to the visual system. Oxidative stress plays a key role in the development and progression of the disease. The aims of the present study were to evaluate the mitochondrial function and its participation in the brain redox metabolism in an experimental glaucoma model. 3-month-old female Wistar rats were subjected to cauterization of two episcleral veins of the left eye to elevate the intraocular pressure. Seven days after surgery, animals were sacrificed, the brain was carefully removed and the primary visual cortex was dissected. Mitochondrial bioenergetics and ROS production, and the antioxidant enzyme defenses from both mitochondrial and cytosolic fractions were evaluated. When compared to control, glaucoma decreased mitochondrial ATP production (23%, p < 0.05), with an increase in superoxide and hydrogen peroxide production (30%, p < 0.01 and 28%, p < 0.05, respectively), whereas no changes were observed in membrane potential and oxygen consumption rate. In addition, the glaucoma group displayed a decrease in complex II activity (34%, p < 0.01). Moreover, NOX4 expression was increased in glaucoma compared to the control group (27%, p < 0.05). Regarding the activity of enzymes associated with the regulation of the redox status, glaucoma showed an increase in mitochondrial SOD activity (34%, p < 0.05), mostly due to an increase in Mn-SOD (50%, p < 0.05). A decrease in mitochondrial GST activity was observed (11%, p < 0.05). GR and TrxR activity were decreased in both mitochondrial (16%, p < 0.05 and 20%, p < 0.05 respectively) and cytosolic (21%, p < 0.01 and 50%, p < 0.01 respectively) fractions in the glaucoma group. Additionally, glaucoma showed an increase in cytoplasmatic GPx (50%, p < 0.01). In this scenario, redox imbalance took place resulting in damage to mitochondrial lipids (39%, p < 0.01) and proteins (70%, p < 0.05). These results suggest that glaucoma leads to mitochondrial function impairment in brain visual targets, that is accompanied by an alteration in both mitochondrial and cytoplasmatic enzymatic defenses. As a consequence of redox imbalance, oxidative damage to macromolecules takes place and can further affect vital cellular functions. Understanding the role of the mitochondria in the development and progression of the disease could bring up new neuroprotective therapies.

Brinzolamide/brimonidine fixed-dose combination bid as an adjunct to a prostaglandin analog for open-angle glaucoma/ocular hypertension.

PURPOSE: To evaluate the additive intraocular pressure-lowering effect of twice-daily brinzolamide 1%/brimonidine 0.2% fixed-dose combination (BBFC) as an adjunct to a prostaglandin analog (PGA) in patients with open-angle glaucoma or ocular hypertension insufficiently controlled with PGA monotherapy. METHODS: In this Phase 4, double-masked trial, patients aged ⩾18 years, with a mean intraocular pressure of ⩾19 and <32 mm Hg in at least one eye were randomized (1:1) to receive BBFC + PGA (n = 96) or vehicle + PGA (n = 92) for 6 weeks. The primary endpoint was the mean change in diurnal intraocular pressure from baseline (averaged over 09:00 and 11:00 h) at Week 6. RESULTS: The mean diurnal intraocular pressure at baseline was similar in the BBFC + PGA (22.8 mm Hg) and vehicle + PGA (22.9 mm Hg) groups. The least squares mean change in diurnal intraocular pressure from baseline at Week 6 was greater with BBFC + PGA (-5.59 mm Hg (95% confidence interval: -6.2 to -5.0)) than with vehicle + PGA (-2.15 mm Hg (95% confidence interval: -2.7 to -1.6)); the treatment difference was statistically significant in favor of BBFC + PGA (-3.44 mm Hg, (95% confidence interval: -4.2 to -2.7); p < 0.001). Ocular adverse events were reported in 21.1% and 8.7% of patients in the BBFC + PGA and vehicle + PGA groups, respectively. The most frequent ocular adverse event was ocular hyperemia (5.3%) in the BBFC + PGA group and blurred vision (2.2%) in the vehicle + PGA group. CONCLUSION: BBFC + PGA significantly reduced mean diurnal intraocular pressure than PGA alone in patients with open-angle glaucoma or ocular hypertension. The safety findings with BBFC + PGA were consistent with the known safety profile of the individual medications.

Glaucoma causes redox imbalance in the primary visual cortex by modulating NADPH oxidase-4, iNOS, and Nrf2 pathway in a rat experimental model.

The aim of this study was to elucidate the intracellular sources of oxidant species, the antioxidant response as well as the main signaling pathways involved in the regulation of the redox balance in the primary visual cortex of rats subjected to an experimental glaucoma model. 3-month female Wistar strain rats were operated under a microscope by cauterizing two of the episcleral veins in order to elevate the intraocular pressure (glaucoma group); the control group received a sham procedure. Seven days after surgery, the animals were sacrificed, the brains were carefully removed, and the primary visual cortex was dissected. NADPH oxidase (NOX) activity, as well as the inducible nitric oxide synthase (iNOS) expression, the enzymatic antioxidant defenses, the metabolism of glutathione, and the translocation of Nuclear factor-erythroid 2-related factor-2 (Nrf2) and Nuclear factor k-light-chain-enhancer of activated B cells (NF-κB) were assessed. Compared to control, glaucoma group displayed an increase in NOX activity (147%, p < 0.05), leading to a rise in the steady state concentration of oxidant species. Specifically, NOX4 expression was higher (90%, p < 0.05), suggesting that it could be a source of H2O2. In addition, iNOS expression was increased in glaucoma (47%, p < 0.05), as a source of NO in the brain, induced by NF-κB translocation to the nucleus (48%, p < 0.01). An increase in primary antioxidant enzymes superoxide dismutase (40%, p < 0.01) and glutathione peroxidase (55%, p < 0.05) was observed as an adaptive response to reactive oxygen species (ROS) production. However, an alteration in glutathione metabolism was shown in glaucoma due to a decrease in its recycling (40%, p < 0.05) as well as in its de novo synthesis (53%, p < 0.05), leading to a decreased in reduced/oxidized glutathione ratio (55%, p < 0.001). Moreover, a lower expression of Nfr2 was shown in glaucoma (40%, p < 0.05), suggesting that the cell signaling pathway that regulates the antioxidant capacity is compromised. In this context, redox imbalance takes place, resulting in oxidative damage to both lipids (70%, p < 0.001) and proteins (140%, p < 0.001). These results suggest that glaucoma damages not only eye structures but also brain visual targets such as the primary visual cortex. Redox imbalance takes place due to an enhancement in ROS and reactive nitrogen species production from different sources, such as NOX family and iNOS, respectively, in an onset where the antioxidant defenses are overwhelmed due to an impaired Nrf2 signaling, leading to oxidative damage to macromolecules.

Maximum Medical Therapy: Brinzolamide/Brimonidine And Travoprost/Timolol Fixed-Dose Combinations In Glaucoma And Ocular Hypertension.

INTRODUCTION: Maximal medical therapy (MMT) is the use of ≥3 classes of topical anti-glaucoma agents to achieve maximal intraocular pressure (IOP) reduction while minimizing adverse effects and compliance challenges. PURPOSE: To evaluate the additive IOP-lowering effect of twice-daily brinzolamide 1%/brimonidine 0.2% fixed-dose combination (BBFC) used adjunctively with once daily travoprost 0.004%/timolol 0.5% fixed-dose combination (TTFC) in patients with open-angle glaucoma (OAG)/ocular hypertension (OHT). METHODS: In this phase IV, double-masked study, patients on TTFC for ≥28 days, aged ≥18 years, with mean IOP ≥19 and ≤28 mmHg in at least 1 eye were randomized to receive BBFC+TTFC (n=67) or vehicle+TTFC (n=67) for 6 weeks. The primary endpoint was mean change in diurnal IOP from baseline (BL, averaged over 09:00 and 11:00) at Week 6. RESULTS: The study was terminated prematurely due to recruitment challenges. BL mean IOP was similar in both groups (BBFC+TTFC: 21.6±1.78 mmHg; vehicle+TTFC: 21.8±1.90 mmHg). Mean change in diurnal IOP from BL at Week 6 was greater with BBFC+TTFC (-4.25 mmHg, 95% confidence interval [CI]: -4.7, -3.8) than with vehicle+TTFC (-2.11 mmHg, 95% CI: -2.6, -1.6, treatment difference, -2.15 mmHg (95% CI: -2.8, -1.5; P<0.001). Ocular adverse events (AEs) were reported in 11.9% of patients given BBFC+TTFC and 7.5% of patients given vehicle+TTFC. The AE with highest frequency was punctate keratitis (3%) in the BBFC+TTFC group; eye irritation (3%) in the vehicle+TTFC group. CONCLUSION: BBFC+TTFC as MMT demonstrated clinically relevant and statistically significant reductions in mean diurnal IOP in patients with OAG/OHT. AEs were consistent with known safety profiles of individual medications.

Genetic association study of exfoliation syndrome identifies a protective rare variant at LOXL1 and five new susceptibility loci.

Exfoliation syndrome (XFS) is the most common known risk factor for secondary glaucoma and a major cause of blindness worldwide. Variants in two genes, LOXL1 and CACNA1A, have previously been associated with XFS. To further elucidate the genetic basis of XFS, we collected a global sample of XFS cases to refine the association at LOXL1, which previously showed inconsistent results across populations, and to identify new variants associated with XFS. We identified a rare protective allele at LOXL1 (p.Phe407, odds ratio (OR) = 25, P = 2.9 × 10-14) through deep resequencing of XFS cases and controls from nine countries. A genome-wide association study (GWAS) of XFS cases and controls from 24 countries followed by replication in 18 countries identified seven genome-wide significant loci (P < 5 × 10-8). We identified association signals at 13q12 (POMP), 11q23.3 (TMEM136), 6p21 (AGPAT1), 3p24 (RBMS3) and 5q23 (near SEMA6A). These findings provide biological insights into the pathology of XFS and highlight a potential role for naturally occurring rare LOXL1 variants in disease biology.

RAND-like appropriateness methodology consensus for primary open-angle glaucoma in Latin America.

PURPOSE: To report the results of a Latin American consensus panel regarding the diagnosis and management of primary open-angle glaucoma and to compare these results with those from a similar panel in the United States. DESIGN: A RAND-like (Research and Development) appropriateness methodology was used to assess glaucoma practice in Latin America. METHODS: The 148 polling statements created for the RAND- like analysis in the United States and 10 additional statements specific to glaucoma care in Latin America were presented to a panel of Latin American glaucoma experts. Panelists were polled in private using the RAND- like methodology before and after the panel meeting. RESULTS: Consensus agreement or disagreement among Latin American experts was reached for 51.3% of statements before the meeting and increased to 66.5% in the private, anonymous meeting after polling (79.0% agreement, 21.0% disagreement). Although there was a high degree of concordance (111 of 148 statements; 75%) between the results of this Latin American panel and the United States panel, there were some notable exceptions relating to diagnostic and therapeutic decision making. CONCLUSIONS: This RAND-like consensus methodology provides a perspective of how Latin American glaucoma practitioners view many aspects of glaucoma and compares these results with those obtained using a similar methodology from practitioners in the United States. These findings may be helpful to ophthalmologists providing glaucoma care in Latin America and in other regions of the world.

During glaucoma, alpha2-macroglobulin accumulates in aqueous humor and binds to nerve growth factor, neutralizing neuroprotection.

PURPOSE: Glaucoma is an optic neuropathy caused by the chronic and progressive death of retinal ganglion cells (RGCs), resulting in irreversible blindness. Ocular hypertension is a major risk factor, but RGC death often continues after ocular hypertension is normalized, and can take place with normal tension. Continuous RGC death was related in rodents and humans to the local upregulation of neurotoxic proteins, such as TNF-α. In rat models of glaucoma, ocular hypertension also upregulates the expression of α2-macroglobulin, which is neurotoxic. α2-macroglobulin upregulation in the retina is long-lived, even after high IOP is reduced with medication. α2-macroglobulin is examined as a possible biomarker in human glaucoma, and a possible neurotoxic mechanism of action is sought. METHODS: Quantitative Western blotting of α2-macroglobulin in samples obtained from aqueous humor (human and rat) and retina (rat) was conducted. Ex vivo neuronal survival assays and nerve growth factor-α2-macroglobulin binding studies using surface plasmon resonance were used. RESULTS: Increased soluble α2-macroglobulin protein is also present in the aqueous humor in a rat glaucoma model, as well as in the aqueous humor of human glaucoma patients but not in cataract patients. One mechanism by which α2-macroglobulin is neurotoxic is by inhibiting the neuroprotective activity of nerve growth factor via TrkA receptors. CONCLUSIONS: This work further documents a potential novel mechanism of RGC death and a potential biomarker or therapeutic target for glaucoma.

Time course changes of oxidative stress markers in a rat experimental glaucoma model.

PURPOSE: To evaluate the relationship between oxidative stress markers and increased intraocular pressure in experimental glaucoma. METHODS: In vivo chemiluminescence (CL), total antioxidant capacity (TRAP), nitrite concentration (NC), and lipid peroxidation markers (TBARS) were evaluated. Wistar rats (n=18 for each time point) underwent operation, and two episcleral veins were cauterized. RESULTS: Decreases of 22%, 35%, and 27% at 7, 15, and 30 days and an increase of 22% at 60 days in CL were observed in glaucomatous eyes. In optic nerve, TBARS values were 6.9+/-0.5 nmol/mg protein (7 days), 9.4+/-0.4 nmol/mg protein (15 days), 18.0+/-1.2 nmol/mg protein (30 days), and 43.1+/-5.3 nmol/mg protein (60 days) (control, 6.2+/-0.4 nmol/mg protein; P<0.001). NC was 37.0+/-1.8 microM (7 days), 31.4+/-1.2 microM (15 days), 39.6+/-1.3 microM (30 days), and 40.0+/-1.3 microM (60 days) (control, 21.1+/-1.7 microM; P<0.001). In glaucomatous vitreous humor, TRAP decreased by 42% at 15 days and 78% at 60 days (control, 414+/-29 microM; P<0.001). In glaucomatous aqueous humor, TRAP values were 75+/-7 microM (7 days), 54+/-4 microM (15 days), 25+/-4 microM (30 days), and 50+/-3 microM (60 days) (control, 90+/-10 microM; P<0.001). CONCLUSIONS: Reactive species were increased in glaucoma, as evidenced by the increases in CL, TBARS, and NC. The decrease in the antioxidant levels may be a consequence of an increase in oxidative processes.

Oxidative stress markers in aqueous humor of glaucoma patients.

PURPOSE: Oxidative stress and antioxidant status in eye tissues may be associated with glaucomatous damage. The aim of this study was to establish the antioxidant status of aqueous humor of patients with primary open-angle glaucoma. For this purpose the authors measured the total reactive antioxidant potential (TRAP) and the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase, and glutathione peroxidase. DESIGN: Case control study. METHODS: Aqueous humor was obtained at the time of surgery from 24 patients with glaucoma and 24 cataract patients; TRAP was measured by chemiluminescence. Activities of the antioxidant enzymes were measured spectrophotometrically. Superoxide dismutase activity was determined by inhibition of the rate of adrenochrome formation at 480 nm. Catalase activity was evaluated by decrease of H(2)O(2) absorbance at 240 nm. Glutathione peroxidase (GPx) activity was determined following nicotinamide adenine dinucleotide phosphate oxidation at 340 nm. RESULTS: Total reactive antioxidant potential value of the cataract group was 124 +/- 5 micromol/l Trolox. This value was significantly decreased, by 64%, in glaucoma patients. An increase of 57% in SOD activity was observed in glaucoma patients when compared with cataract patients (41.7 +/- 2.7 U SOD/ml). Glutathione activity was threefold higher in glaucoma patients than in the cataract group (6.1 +/- 0.6 U/ml). No significant changes were found in catalase levels. CONCLUSIONS: Oxidative stress may lead to an induction of antioxidant enzymes and contribute to TRAP decrease. Superoxide dismutase, GPx activities, and TRAP may be useful oxidative stress markers in aqueous humor of glaucoma patients.

Características reológicas de los pacientes con glaucoma asociado a pseudoexfoliación capsular / Rheologic characteristicsof the patients with glaucoma ssociated with capsular pseudoexfoliaton

Introducción y propósito: la presencia de pseudoexfoliación capsular está asociada a un mayor número de fenómenos vasculares. El propósito de este trabajo fue evaluar distintos parámetros reológicos enpacientes con glaucoma asociado a pseudoexfoliación capsular. Materiales y métodos: se estudiaron 3 grupos de 15 pacientes cada uno. Grupo A: glaucoma asociado a pseudoexfoliación capsular, B: glaucoma crónico simple, y C: sujetos normales sin glaucoma. Se estudiaron en forma enmascarada los siguientes parámetros: hematocrito, hemoglobina, proteínas plasmáticas, viscosidad plasmática y plaquetas. Resultados: la viscosidad plasmática fuemayor en el grupo A comparado con el B y el C (p < 0,05). No hubo diferencias significativas desde el punto de vista estadístico en los demás parámetros evaluados. Discusión: existe una mayor viscosidad plasmática en la sangre de pacientes con glaucoma asociado a peudoexfoliación capsular. Estos resultados podrían explicar la mayor frecuencia de fenómenos vasculares observados en la población con pseudoexfoliación capsular.

Características reológicas de los pacientes con glaucoma asociado a pseudoexfoliación capsular / Rheologic characteristicsof the patients with glaucoma ssociated with capsular pseudoexfoliaton

Introducción y propósito: la presencia de pseudoexfoliación capsular está asociada a un mayor número de fenómenos vasculares. El propósito de este trabajo fue evaluar distintos parámetros reológicos enpacientes con glaucoma asociado a pseudoexfoliación capsular. Materiales y métodos: se estudiaron 3 grupos de 15 pacientes cada uno. Grupo A: glaucoma asociado a pseudoexfoliación capsular, B: glaucoma crónico simple, y C: sujetos normales sin glaucoma. Se estudiaron en forma enmascarada los siguientes parámetros: hematocrito, hemoglobina, proteínas plasmáticas, viscosidad plasmática y plaquetas. Resultados: la viscosidad plasmática fuemayor en el grupo A comparado con el B y el C (p < 0,05). No hubo diferencias significativas desde el punto de vista estadístico en los demás parámetros evaluados. Discusión: existe una mayor viscosidad plasmática en la sangre de pacientes con glaucoma asociado a peudoexfoliación capsular. Estos resultados podrían explicar la mayor frecuencia de fenómenos vasculares observados en la población con pseudoexfoliación capsular.(AU)

Trabeculectomía de pequeña incisión evitando la cápsula de Tenon: una nueva técnica para la cirugía de glaucoma / Trabeculectomy of small incision avoiding the Tenon’s capsule: a new technique for the surgery of glaucoma

Objetivo: presentar una nueva técnica para el tratamiento quirúrgico del glaucoma, que se realiza a través de una pequeña incisión minimizando el daño de la cápsula de Tenon. Material y Métodos: técnica quirúrgica, se realizó una peritomía conjuntival de 1.75 a 2.5 mm sin cortar la inserción de la cápsula de Tenon. Se procedió a realizar una incisión limbar parcial de un tercio a la mitad del espesor del limbo y de 1.75 a 2.5 mm de longitud. Se disecó un bolsillo intraescleral hacia posterior mediante un cuchillete angulado. Se preparó un cistítomo que se pasó a través del bolsillo escleral y se lo rotó hacia superior para penetrar en el espacio subtenoniano. Luego de ingresar en la cámara anterior a nivel de la incisión limbar inicial, se resecó un fragmento del piso del bolsillo escleral, seguido de una iridectomía periférica. A continución se cerró la herida escleral y luego la conjuntival en forma hermética. Pacientes: este procedimiento se realizó en pacientes con glaucoma no controlado con máxima medicación y que tenían indicación de trabeculectomía. Se analizan dos grupos de pacientes. En el grupo A se utilizó una incisión de 2.5 mm; y consistió en 30 ojos de 30 pacientes con un mínimo de seguimiento de 6 meses. Se utilizó 5-Fluorouracilo intraoperatorio en 10 pacientes cuyo diagnóstico constituía un mal pronóstico para la cirugía (glaucoma juvenil, neovascular, traumático, postpseudofaquia o cirugías previas fracasadas). En el grupo B la incisión fue de 1.75 mm; y consistió en 25 ojos de 22 pacientes con mal pronóstico para la cirugía, teniendo un seguimiento mínimo de un año. Se utilizó 5-Fluorouracilo intraoperatorio en todos los casos. Resultados: en el grupo A la presión intraocular (PIO) preoperatoria promedio fue de 34.5ñ8.1 mmHg. La PIO postoperatoria fue de 12.5ñ5.3 mmHg a los 3 meses (p<0.01), y de 13.2ñ4.1 mmHg a los 6 meses (p<0.01). El 90 por ciento de los ojos tuvieron PIO =< 18 mmHg sin medicación a los 6 meses. En el grupo B la PIO presoperatoria promedio fue de 32.5ñ5.4 mmHg. La PIO postoperatoria fue de 15.0ñ5.3 mmHg a los 6 meses (p<0.01), y de 14.04ñ3.6 mmHg al momento del último seguimiento (12 o más meses) (p<0.01). Un total de 23 sobre 25 ojos (91 por ciento) tuvieron la PIO =< 21 mmHg, seis de ellos con medicación. 17 ojos tuvieron la PIO =< 17 mmHg sin medicación y fueron considerados como éxito. 6 ojos tuvieron la PIO entre 18 y 21 (todos con medicación), y fueron considerados como éxito relativo...(TRUNCADO)

Trabeculectomía de pequeña incisión evitando la cápsula de Tenon: una nueva técnica para la cirugía de glaucoma / Trabeculectomy of small incision avoiding the Tenons capsule: a new technique for the surgery of glaucoma

Objetivo: presentar una nueva técnica para el tratamiento quirúrgico del glaucoma, que se realiza a través de una pequeña incisión minimizando el daño de la cápsula de Tenon. Material y Métodos: técnica quirúrgica, se realizó una peritomía conjuntival de 1.75 a 2.5 mm sin cortar la inserción de la cápsula de Tenon. Se procedió a realizar una incisión limbar parcial de un tercio a la mitad del espesor del limbo y de 1.75 a 2.5 mm de longitud. Se disecó un bolsillo intraescleral hacia posterior mediante un cuchillete angulado. Se preparó un cistítomo que se pasó a través del bolsillo escleral y se lo rotó hacia superior para penetrar en el espacio subtenoniano. Luego de ingresar en la cámara anterior a nivel de la incisión limbar inicial, se resecó un fragmento del piso del bolsillo escleral, seguido de una iridectomía periférica. A continución se cerró la herida escleral y luego la conjuntival en forma hermética. Pacientes: este procedimiento se realizó en pacientes con glaucoma no controlado con máxima medicación y que tenían indicación de trabeculectomía. Se analizan dos grupos de pacientes. En el grupo A se utilizó una incisión de 2.5 mm; y consistió en 30 ojos de 30 pacientes con un mínimo de seguimiento de 6 meses. Se utilizó 5-Fluorouracilo intraoperatorio en 10 pacientes cuyo diagnóstico constituía un mal pronóstico para la cirugía (glaucoma juvenil, neovascular, traumático, postpseudofaquia o cirugías previas fracasadas). En el grupo B la incisión fue de 1.75 mm; y consistió en 25 ojos de 22 pacientes con mal pronóstico para la cirugía, teniendo un seguimiento mínimo de un año. Se utilizó 5-Fluorouracilo intraoperatorio en todos los casos. Resultados: en el grupo A la presión intraocular (PIO) preoperatoria promedio fue de 34.5ñ8.1 mmHg. La PIO postoperatoria fue de 12.5ñ5.3 mmHg a los 3 meses (p<0.01), y de 13.2ñ4.1 mmHg a los 6 meses (p<0.01). El 90 por ciento de los ojos tuvieron PIO =< 18 mmHg sin medicación a los 6 meses. En el grupo B la PIO presoperatoria promedio fue de 32.5ñ5.4 mmHg. La PIO postoperatoria fue de 15.0ñ5.3 mmHg a los 6 meses (p<0.01), y de 14.04ñ3.6 mmHg al momento del último seguimiento (12 o más meses) (p<0.01). Un total de 23 sobre 25 ojos (91 por ciento) tuvieron la PIO =< 21 mmHg, seis de ellos con medicación. 17 ojos tuvieron la PIO =< 17 mmHg sin medicación y fueron considerados como éxito. 6 ojos tuvieron la PIO entre 18 y 21 (todos con medicación), y fueron considerados como éxito relativo...(TRUNCADO)(AU)