El presente trabajo es una adaptación de la técnica quirúrgica de trabeculectomía para el tratamiento del glaucoma canino. Para tal fin se utilizaron 5 caninos de distintos sexos, razas y edades, con una historia clínica de glaucoma. Ellos fueron intervenidos en la Clínica de Animales Menores de la Facultad de Medicina Veterinaria de la Universidad Nacional Mayor de San Marcos, empleándose la técnica quirúrgica de trabeculectomía, la cual consiste en crear una nueva vía de drenaje del humor acuoso. En cada uno de los casos, se demostró que dicha técnica es una alternativa, rápida, poco costosa y confiable para el tratamiento resolutivo de esta patología. Con el fin de verificar su eficacia se realizaron evaluaciones oftalmológicas post-quirúrgicas. Los hallazgos mostraron en todos los casos una importante disminución de la presión intraocular. Al comparar las presiones intraoculares antes y después de la intervención quirúrgica se encontró una diferencia estadística significativa con un nivel de confiabilidad del 99%. Se concluye que la técnica quirúrgica de trabeculectomía puede ser usada en la resolución del aumento de la presión intraocular en caninos. / The present work in an adjustment of the surgical technique of trabeculectomy for the treatment of the canine glaucoma. To accomplish it, 5 canines of different sex, races and age, with clinical history of glaucoma were used. They were treated in the Clinic of Small Animals of the Faculty of Veterinary Medicine of the National University of San Marcos. The surgical technique of trabeculectomy permitted to find a new way of draining of the aqueous humor. In each of the cases, there was demonstrated that the technique is a quick, cheap and reliable alternative for treatment of this pathology. In order to verify its efficiency, postsurgical evaluations were done. In all the case the findings showed an important decrease of the intraocular pressure. When comparing the intraocular pressures before an after the surgical intervention. There was found a significative statistical difference, with 99% of reliance. It is concluded that the surgical technique of trabeculectomy can be used successfully in the treatment of the increase of he intraocular pressure in canine.

Objetivo: Determinar la diferencias en las mediciones de tonometría de contorno dinámico (TCD) y la tonometría de aplanación (TAG) al relacionarlas con el grosor y la curvatura corneal. Materiales y métodos: Estudio transversal, comparativo. Se obtuvo una muestra por conveniencia, esto incluyó a 116 ojos de pacientes que acudieron al programa social del Instituto de Ojos Oftalmosalud, sin patología ocular demostrada, entre los meses de febrero a Abril del 2009. Se tomaron medidas del grosor, curvatura corneal, presión intraocular por TCD y TAG Resultados: La edad promedio de los participantes fue 55 años, el 52.58% varones. La media de la PIO por contorno dinámico fue 19.3 mm Hg y de la tonometría de aplanación 16.32 mm Hg, existiendo diferencias significativas entre ambas mediciones de PIO (p menor 0,0006). El grosor de la córnea central por paquimetría fue 539.4 en promedio y la media de la curvatura corneal en dioptrías de 43.28. Las comparaciones de las medias de la PIO de la TAG y TCD según el grosor corneal central (GCC) son significativas en las medidas menores a 500 micras (p menor 0.000001). Según la curvatura corneal se mantienen estas diferencias de manera significativa, es mayor con el TCD. Conclusiones: La tonometría de contorno dinámico sobreestima significativamente la PIO comparada con la tonometría de aplanación. La PIO evaluada con ambos instrumentos comparadas con el grosor corneal muestran diferencias significativas, siendo similares en córneas entre 500 a 549 micras. / Objective: To determine the differences in the measurements of Dynamic contour tonometry and Goldmann applanation tonometry in relation with the thickness and the corneal curvature. Methodology: Study transverse, a sample was obtained by convenience, included 116 patients’ eyes went to the Oftalmosalud social program, without ocular pathology, showed through February to April, 2009. They took measures of the thickness, corneal curvature, pressure for CDT and AGT. Results: The age average of the participants was of 55 years, 52.58% males. The stocking of the IOP one for contour dinamic was 19.3 mmHg and for applanation tonometry 16.32mmHg, existing significant differences among both mensurations of IOP (p less 0, 0006). The thickness of the central cornea for paquimetry was 539.4 on the average and the stocking of the corneal bend in dioptrias of 43.28. The comparisons of the stockings of the IOP one of AGT and CDT according to the thickness corneal power station (CCT) are significant in the measures smaller to 500 microns (p less 0.000001). According to the corneal curvature stays with significant differences ways being bigger with CDT. Conclusions: The tonometry of contour dinamic overestimates the IOP one compared with the applanation tonometry significantly. The IOP one evaluated with both instruments compared with the corneal thickness shows significant differences, being similar in corneas among 500 to 549 microns.

The purpose of this thesis was to investigate the effect of corneal swelling on the accuracy of Goldmann tonometry estimates of intraocular pressure (IOP). In the first experiment, central corneal thickness (CCT, ultrasonic pachymetry), IOP (Goldmann tonometry) and corneal curvature (keratometry) was measured in one eye of 25 subjects every two hours for 24 hours, except for 8 hours overnight (no measurements taken), and for the first two hours after awakening (measurement frequency 20 minutes). CCT (+20.1??10.9 pm) and IOP (+3.1??2.4 mmHg) peaked on eye opening, and then decreased at a similar rate (r=0.967, p<0.001) for the next two hours. Corneal swelling may have influenced the accuracy of Goldmann IOP measurements during this time. In the second and third studies, the CCT, IOP and corneal curvature were measured in both eyes of two groups of 25 subjects before and after the induction of corneal swelling, resulting from two hours of monocular closed eye contact lens wear. The increase in IOP was correlated to the increase in CCT at a rate of 0.33 to 0.48 mmHg per 10 pm, which signified an overestimation error in Goldmann IOP measurement. However, the change in IOP could not be accounted for solely by the change in CCT. In the fourth study, CCT, IOP and corneal curvature were used in conjunction with the Orssengo-Pye algorithm to determine the range of Young's modulus in the normal population, which was 0.29??0.06 MPa. Physiological variations in Young's modulus had a similar effect on Goldmann tonometry to CCT. In the fifth study, the data collected for studies 2 and 3 was used to calculate the Young's modulus changes associated with corneal swelling, again with the assistance of the Orssengo-Pye algorithm. No systematic change in Young's modulus was recorded after contact lens wear, but the model suggested that corneal biomechanical changes were responsible for the remainder of the change in IOP. All experimental results were combined to develop a model to calculate the diurnal variation of Goldmann IOP errors. The likely error in IOP due to overnight corneal swelling was 0.6 to 1.4 mmHg, which may explain as much as 45% (1.4 mmHg) of the 3.1 mmHg diurnal variation of IOP. In summary, small amounts of corneal swelling were shown to have a clinically significant impact on the accuracy of Goldmann tonometry. This may interfere with the measurement of the diurnal variation of IOP, particularly if measurements are taken prior to the resolution of overnight corneal swelling.

Made available in DSpace on 2014-06-11T19:23:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-16Bitstream added on 2014-06-13T20:50:54Z : No. of bitstreams: 1 renzo_r_me_jabo.pdf: 301706 bytes, checksum: 7ba09919044057e80244fe4b39f2b41e (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Estudaram-se a pressão intraocular, a densidade e a hexagonalidade de células endoteliais, níveis de Prostaglandina E2 e sua correlação com catarata senil madura (n=8) ou hipermatura (n=8). Adicionalmente, foram utilizados valores de Prostaglandina E2 do humor aquoso de cães oftalmologicamente saudáveis (n=7). Para avaliação da pressão intraocular empregou-se tonometria digital de aplanação. A avaliação da densidade e da hexagonalidade das células endoteliais foi realizada por meio de microscopia especular de não contato. Sob anestesia geral, 0,2mL de humor aquoso foram colhidos por meio de paracentese da câmara anterior. As amostras de aquoso foram congeladas e armazenadas à -80 oC para mensuração da concentração de PGE2, por imunoensaio enzimático competitivo. Os valores foram comparados estatisticamente, empregando-se análise de variância de via única, e o teste de múltiplas comparações de Bonferroni. Teste t não pareado foi utilizado para se avaliar os dados obtidos por microscopia especular. Possíveis correlações entre os resultados foram comparadas aplicando-se o teste de Person. Adotou-se nível de significância de p<0,05. Em ambos os grupos observou-se diminuição significativa da pressão intraocular (PIO), entretanto não houve diferença entre eles (p = 0,90). As médias dos valores de densidade celular (CD) e de hexagonalidade (HEX) foram 2253,363 cell/mm² e 59,03% para GSM e 2058,325 cell/mm² e 63,75% para GSH, respectivamente. Entretanto não houve diferença significativa entre ambos, tanto para CD (p=0,201), quanto para HEX (p=0,61). Observou-se incremento nos valores de PGE2 nos grupos com catarata em relação aos cães oftalmologicamente saudáveis (p<0,001), entretanto, não houve diferença significativa entre os grupos com catarata... / Intraocular pressure, endothelial cell density and hexagonality, and aqueous humor prostaglandin E2 (PGE2) were studied and correlated in dogs with mature (n=8) and hypermature (n=8) senil cataratcs. In addition, aqueous humor PGE2 values of ophthalmic healthy dogs (n=7) were used. Non contact specular microscopy was used to evaluate density and hexagonality of endothelial cells. 0.2mL of aqueous humor was collected by means of anterior chamber paracentesis. Aqueous humor samples were frozen at -80 oC and concentration of PGE2 were quantified by means of competitive enzyme immunoassay. PGE2 values were statistically compared with one way analysis of variance and Bonferroni´s multi comparison test. Specular microscopy data were assessed by means of unparied T test. Person´s test was used in order to assess possible correlations among data. Significance was set at value of P < 0.05. Values of endothelial cell density and hexagonality did not change significantly between groups (P = 0.61). PGE2 values were significantly higher in dogs with cataract, when compared with ophthalmic healthy dogs (P < 0.001), however, this parameter did not change significantly between mature and hypermature groups (P > 0.05). Is it possible tosay that cataract patients in stages of maturity or hipermaturity develop uveitis... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:23:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2004Bitstream added on 2014-06-13T19:30:13Z : No. of bitstreams: 1 borges_ag_me_botfmvz.pdf: 619936 bytes, checksum: 26f3dbd1632fca5d2ec5d73fee61d030 (MD5) / Dentre as doenças oculares diagnosticadas no cão, o glaucoma reveste-se de singular importância, como afecção potencial causadora de cegueira. O aumento da pressão intra-ocular (PIO) é o fator de risco primário para o desenvolvimento da neuropatia óptica glaucomatosa canina. A dorzolamida e o timolol, fármacos utilizados para o tratamento do glaucoma, reduzem a PIO pela diminuição da produção do humor aquoso, embora utilizem diferentes mecanismos de ação. O objetivo do trabalho foi avaliar o efeito do cloridrato de dorzolamida 2%, maleato de timolol 0,5% e da combinação de ambos na pressão intra-ocular de cães normais e verificar possíveis alterações na PIO do olho contra-lateral sem tratamento. Foram utilizados 60 cães, distribuídos em três grupos (G) aleatórios de 20 animais. Cada grupo recebeu tratamento tópico no olho esquerdo com timolol 0,5% (GT), dorzolamida 2% (GD) ou a combinação, timolol 0,5% e dorzolamida 2% (GTD). Em todos os grupos, a mensuração da PIO foi realizada utilizando-se tonômetro de aplanação (Tonopen). As medidas foram realizadas, em ambos os olhos, uma hora antes e uma, duas, quatro, seis e oito horas após a instilação de uma gota do colírio no olho esquerdo. No olho tratado percentual de redução máxima da associação timolol/dorzolamida foi numericamente superior (27%) comparado ao timolol (21,9%) e dorzolamida (22,4%) quando utilizados como monoterapia. O olho não tratado apresentou uma redução significativa da PIO, sendo que a redução máxima para o GT foi de 7%, para o GD de 13,8% e para o GTD de 13,6%. A dorzolamida e a associação timolol/dorzolamida promoveram uma ação redutora maior, após uma e seis horas da sua instilação no olho tratado. A administração tópica do timolol 0,5%, dorzolamida a 2% como monoterapia e a associação fixa destes fármacos resultou na redução significativa da PIO de cães clinicamente normais. / Glaucoma is one of the most important ocular diseases in the dog. Increased intraocular pressure (IOP) is the major risk factor for the development of glaucoma. Dorzolamide and timolol are drugs used for the treatment of glaucoma. Both drugs modify aqueous humor outflow by different mechanisms, resulting in decreased IOP. The aim of this work was to evaluate the efficacy of dorzolamide hydrochloride, timolol maleate and the combination of both drugs on IOP of healthy dogs. Sixty adult dogs were randomly and equally assigned to three groups (n = 20 per group). Each group received topical treatment in the left eye with 0,5% timolol, 2% dorzolamide or the combination (0,5% timolol / 2% dorzolamide). IOP measurements were made using aplanation tonometry (Tono-pen) after local instillation of 0,5% proparacaine in he both eyes. Measurements were performed 1 hour before (baseline) instillation of a single drop of the test drugs in the left eye, and at 1, 2, 4, 6 and 8 hours after treatment. Similar measurements were also performed in the right eye (nontreated eye). In the nontreated eye, IOP decreased over time, with a maximum decrease from baseline of 7%, 13,8% and 13,6% in the timolol, dorzolamide e timolol/dorzolamide groups, respectively. In the treated eye, there was a greater reduction in IOP for the combination (27% maximum decrease from baseline) when compared with timolol (21,9%) and dorzolamide (22,4%) groups. Dorzolamide and timolol/dorzolamide caused greater decreases in IOP at 1 and 6 hours after drug instillation. It was concluded that 0,5% timolol, 2% dorzolamide and the combination of these drugs are effective in reducing IOP in healthy dogs.

Orientador: Cláudia Valéria Seullner Brandão / Resumo: Dentre as doenças oculares diagnosticadas no cão, o glaucoma reveste-se de singular importância, como afecção potencial causadora de cegueira. O aumento da pressão intra-ocular (PIO) é o fator de risco primário para o desenvolvimento da neuropatia óptica glaucomatosa canina. A dorzolamida e o timolol, fármacos utilizados para o tratamento do glaucoma, reduzem a PIO pela diminuição da produção do humor aquoso, embora utilizem diferentes mecanismos de ação. O objetivo do trabalho foi avaliar o efeito do cloridrato de dorzolamida 2%, maleato de timolol 0,5% e da combinação de ambos na pressão intra-ocular de cães normais e verificar possíveis alterações na PIO do olho contra-lateral sem tratamento. Foram utilizados 60 cães, distribuídos em três grupos (G) aleatórios de 20 animais. Cada grupo recebeu tratamento tópico no olho esquerdo com timolol 0,5% (GT), dorzolamida 2% (GD) ou a combinação, timolol 0,5% e dorzolamida 2% (GTD). Em todos os grupos, a mensuração da PIO foi realizada utilizando-se tonômetro de aplanação (Tonopen). As medidas foram realizadas, em ambos os olhos, uma hora antes e uma, duas, quatro, seis e oito horas após a instilação de uma gota do colírio no olho esquerdo. No olho tratado percentual de redução máxima da associação timolol/dorzolamida foi numericamente superior (27%) comparado ao timolol (21,9%) e dorzolamida (22,4%) quando utilizados como monoterapia. O olho não tratado apresentou uma redução significativa da PIO, sendo que a redução máxima para o GT foi de 7%, para o GD de 13,8% e para o GTD de 13,6%. A dorzolamida e a associação timolol/dorzolamida promoveram uma ação redutora maior, após uma e seis horas da sua instilação no olho tratado. A administração tópica do timolol 0,5%, dorzolamida a 2% como monoterapia e a associação fixa destes fármacos resultou na redução significativa da PIO de cães clinicamente normais. / Abstract: Glaucoma is one of the most important ocular diseases in the dog. Increased intraocular pressure (IOP) is the major risk factor for the development of glaucoma. Dorzolamide and timolol are drugs used for the treatment of glaucoma. Both drugs modify aqueous humor outflow by different mechanisms, resulting in decreased IOP. The aim of this work was to evaluate the efficacy of dorzolamide hydrochloride, timolol maleate and the combination of both drugs on IOP of healthy dogs. Sixty adult dogs were randomly and equally assigned to three groups (n = 20 per group). Each group received topical treatment in the left eye with 0,5% timolol, 2% dorzolamide or the combination (0,5% timolol / 2% dorzolamide). IOP measurements were made using aplanation tonometry (Tono-pen) after local instillation of 0,5% proparacaine in he both eyes. Measurements were performed 1 hour before (baseline) instillation of a single drop of the test drugs in the left eye, and at 1, 2, 4, 6 and 8 hours after treatment. Similar measurements were also performed in the right eye (nontreated eye). In the nontreated eye, IOP decreased over time, with a maximum decrease from baseline of 7%, 13,8% and 13,6% in the timolol, dorzolamide e timolol/dorzolamide groups, respectively. In the treated eye, there was a greater reduction in IOP for the combination (27% maximum decrease from baseline) when compared with timolol (21,9%) and dorzolamide (22,4%) groups. Dorzolamide and timolol/dorzolamide caused greater decreases in IOP at 1 and 6 hours after drug instillation. It was concluded that 0,5% timolol, 2% dorzolamide and the combination of these drugs are effective in reducing IOP in healthy dogs. / Mestre

Clinical relevance: Mobility and fall risk may be important considerations in choosing between intraocular lenses. Background: Fall risk in older adults increases when wearing multifocal spectacles, but little is known about mobility among individuals with different types of intraocular lenses. This study compared visual function, fall risk and balance control following bilateral implantation of monofocal or multifocal intraocular lenses. Methods: This was a non-randomised, cross-sectional study involving adults with bilateral intraocular lenses. Participants completed questionnaires concerning physical functioning, fall history and balance-related confidence. Binocular visual acuity, contrast sensitivity (Pelli-Robson chart and computerized testing), depth perception and glare sensitivity were assessed. Physical performance measures included the Sensory Organization Test, preferred gait speed, Dynamic Gait Index and wayfinding in a virtual environment. Results: Fifteen participants (mean ± standard deviation, 67.1 ± 6.8 years) had monofocal intraocular lenses and 14 participants (68.1 ± 6.1 years) had multifocal intraocular lenses. Contrast sensitivity in the monofocal group was significantly better than that in the multifocal group (p = 0.02) at intermediate and high spatial frequencies. Contrast sensitivity of the monofocal group also was less affected by glare than the contrast sensitivity of the multifocal group, at an intermediate spatial frequency (p = 0.02). However, the multifocal group had significantly better Dynamic Gait Index scores (p = 0.04), even after controlling for perceived physical function. Conclusions: The participants with monofocal intraocular lenses generally had better contrast sensitivity than did those with multifocal intraocular lenses. However, the scores on a mobility test that is associated with fall risk were worse for those with monofocal lenses.

Ocular disease is one of the most common problems encountered in sea lions at various zoos and aquariums around the world.1 The California sea lion (Zalophus californianus) is one of the most common marine mammals maintained in zoos and is also the most commonly afflicted with ocular disease. Studies have shown that pinnipeds housed in captivity manifest an array of ocular lesions.2 Eye disease can range from a pinpoint corneal opacity to loss of vision due to keratopathy, cataracts and secondary glaucoma. Glaucoma is a disease that has not been extensively studied in the sea lion.3 Observation of clinical signs and determination of intraocular pressures (IOP) are critical for early diagnosis. IOP measurement may elucidate intraocular disease and provides information on the balance between aqueous humor production and outflow. The objective of this study is to measure IOP in California sea lions that have clinically normal eyes as well as those with varying degrees of ocular diseases, and to evaluate the incidence of secondary glaucoma in this species.

Previously, we showed that transcription factor activating protein 2-beta (AP-2β) deletion from the periocular mesenchyme (POM)-derived neural crest cells (NCCs) using Wnt1Cre (AP-2β NCC knockouts/AP-2β NCC KOs) resulted in anterior segment abnormalities and increased intraocular pressure (IOP). The present study investigated the role of AP-2β in development of structures of the conventional pathway including the trabecular meshwork and Schlemm’s canal, and the unconventional pathway including the ciliary muscle. Studies using NCC KOs revealed that the embryonic POM migrated appropriately, but a significant reduction in postnatal POM cell proliferation in the angle was observed, accompanied by reduced expression of trabecular meshwork and Schlemm's canal markers when compared to controls, which likely contributed to the elevated IOP in NCC KOs. However, since Wnt1Cre was expressed in multiple NCC derivatives, AP-2β was deleted specifically from the developing trabecular meshwork region (TMR) using Mgp-Cre knock-in (Mgp-Cre.KI) mice. Although migration of the POM giving rise to the trabecular meshwork was not affected, peripheral anterior synechia (PAS), a decrease in expression of trabecular meshwork and Schlemm’s canal markers, and significantly increased IOP was observed in TMR KOs compared to controls, paired with loss of retinal ganglion cells (RGCs), and reduced retinal thickness and function. However, treatment with latanoprost, a prostaglandin analog that increases outflow through the unconventional pathway, significantly reduced elevated IOP in TMR KOs. Overall, the results suggest that AP-2β plays a cell-autonomous role in trabecular meshwork development and a non-cell-autonomous role in Schlemm’s canal development, while also playing an indirect role in unconventional pathway function, and thus, is important for IOP homeostasis. Moreover, the AP-2β NCC KO and AP-2β TMR KO may serve as models of primary angle closure glaucoma that can be used to test IOP-lowering drugs, molecular targets and neuroprotective strategies to develop treatments for human glaucoma. / Thesis / Doctor of Philosophy (PhD) / Glaucoma is the leading cause of irreversible blindness worldwide. Primary angle closure glaucoma is one type of glaucoma resulting from abnormalities in structures that allow aqueous humour found in the front of the eye from exiting the eye through two major routes, including the conventional and unconventional pathways. Defects in these structures lead to increased intraocular pressure (IOP) that damages specialized cells important for vision. This project examines the role of transcription factor activating protein 2-beta (AP-2β) in development of structures responsible for IOP balance. Data from the current study showed that AP-2β is required for formation of the structures of the conventional pathway, but does not directly affect development of unconventional pathway structures. The two AP-2β deletion mutants used here can model human primary angle closure glaucoma to test the effect of various drugs and cell protection strategies aimed at treating glaucoma.

No / Aspheric intraocular lenses (IOLs) are designed to correct spherical aberration in pseudophakic eyes. We predict the benefit from correcting spherical aberration based on simulations and aberrometry of pseudophakic eyes implanted with spherical IOLs. METHODS Ray tracing was performed through a model eye with an equi-biconvex spherical IOL and with a spherical aberration-correcting aspheric IOL. The IOLs were increasingly tilted and/or displaced, and the resulting transverse aberrations of 169 rays were transformed into Zernike coefficients for different pupil sizes. The benefit from correcting spherical aberration at individual mesopic pupils was investigated by canceling in the sets of Zernike coefficients for 41 eyes implanted with a spherical IOL. RESULTS Both the model eye and the real eye data predict that age-related miosis reduces spherical aberration in the eye implanted with a spherical IOL to approximately 1/3 of the spherical aberration at a 6-mm pupil. A reduction of similar magnitude occurs when spherical aberration-induced non-paraxial defocus is corrected by a spectacle lens. For natural mesopic pupils, canceling the Zernike coefficient improved the objective image quality at a rate similar to changing defocus by 0.05 diopters. Average centration and tilt levels diminish the lead of aspheric IOLs over spherical IOLs, depending on the direction of decentration. CONCLUSIONS The benefit from correcting spherical aberration in a pseudophakic eye is limited for some or all of the following reasons: wearing glasses, age-related miosis, tilt and decentration of IOL, small contribution of spherical aberration to all aberrations, and intersubject variability