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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Efeito das combinações fixas dos análogos de prostaglandina com maleato de timolol sobre a barreira hematoaquosa e hematorretiniana de pacientes pseudofácicos com glaucoma primário de ângulo aberto / Effect of prostaglandin analogues and timolol fixed combinations on the blood-aqueous barrier in pseudophakic patients with open angle glaucoma

Santana, Alana Mendonça, 1981- 24 August 2018 (has links)
Orientador: Vital Paulino Costa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T05:19:20Z (GMT). No. of bitstreams: 1 Santana_AlanaMendonca_M.pdf: 2805390 bytes, checksum: 9512111e988de78a1ffde9d9f877658b (MD5) Previous issue date: 2014 / Resumo: O objetivo deste trabalho foi investigar os efeitos das combinações fixas dos análogos de prostaglandinas com timolol sobre a barreira hematoaquosa, a espessura macular central e a pressão intraocular (PIO), em pacientes pseudofácicos com glaucoma primário de ângulo aberto. Neste ensaio clínico randomizado, com observador mascarado e duração de 6 meses, os pacientes foram tratados uma vez por dia (20:00 horas) com lubrificante (grupo controle) ou com a combinação fixa de maleato de timolol 0,5% e latanoprosta 0,005% (CFLT), maleato de timolol 0,5% e bimatoprosta 0,03% (CFBT) ou maleato de timolol 0,5% e travoprosta 0,004% (CFTT). Foi incluído no estudo apenas um olho de 61 pacientes: CFLT (n=16), CFBT (n=15), CFTT (n=15) e grupo controle (n=15). A barreira hematoaquosa foi avaliada por meio do &quot;laser flare meter¿ antes do início do uso das medicações e após 15 dias, 1,2,3,4,5 e 6 meses de tratamento. A PIO foi medida sempre às 9:00 horas, nas mesmas ocasiões. A espessura macular central foi avaliada por meio da tomografia de coerência óptica antes do uso das medicações, após 1 e 6 meses de tratamento ou na hipótese de piora da acuidade visual. Não houve aumento estatisticamente significante nos valores médios de &quot;flare¿ em comparação aos valores iniciais em todos os grupos (p>0,05) em todas as visitas, exceto no grupo CFTT no primeiro mês (p=0,0476) e no grupo CFLT (p=0,0129) no terceiro mês de seguimento. Não houve diferença estatisticamente significativante entre os valores médios de &quot;flare¿ entre os grupos durante o estudo (p>0,05). A média dos valores da espessura macular central aumentou significativamente nos grupos CFLT (p=0,012) e CFTT (p=0,0419) no primeiro mês de tratamento em relação aos valores iniciais. Não houve aumento estatisticamente significante nos valores médios da espessura macular central em relação aos valores iniciais em todos os grupos após 6 meses de tratamento (p>0,05) e não ocorreu diferença estatisticamente significante entre os grupos durante o estudo (p>0,05). A PIO média inicial foi significativamente menor no grupo controle (p=0,0000). Todas as combinações fixas reduziram significativamente a PIO em todas as visitas (P<0,0001), com efeito hipotensor semelhante entre si (p=0,816). Estes resultados indicam que o uso das combinações fixas de análogos de prostaglandinas com timolol não aumentou significativamente a média dos valores de &quot;flare¿ ou a média da espessura macular após 6 meses de tratamento nesta população / Abstract: The aim of this study was to investigate the effects of prostaglandin analogues and timolol fixed-combinations on the blood-aqueous barrier, central macular thickness and intraocular pressure (IOP) in pseudophakic patients with primary open angle glaucoma. In this randomized, masked-observer, 6-month clinical trial, patients were treated once daily (8 pm) with lubricant eye drops (control group), 0,5% timolol and 0,005% latanoprost fixed-combination (LTFC), 0,5% timolol and 0,03% bimatoprost fixed-combination (BTFC) or 0,5% timolol and 0,004% travoprost fixed-combination (TTFC). One eye of 61 patients were included in the study: LTFC (n=16), BTFC (n=15), TTFC (n=15) and control group (n=15). The blood-aqueous barrier status was assessed using the laser flare meter before the medications were started and after 15 days, 1, 2, 3, 4, 5 and 6 months of treatment. The IOP was measured always at 9 am, at the same intervals. The central macular thickness was evaluated with optical coherence tomography before medications were started, after 1 and 6 months of follow-up or if a patient showed decreased visual acuity at any time during follow-up. There was no significant increase in mean flare measurements from baseline in all groups (p>0.05) in all visits, except TTFC group at 1 month (p=0,0476) and LTFC group at 3 months (p=0,0129). There were no significant differences in mean flare values among the groups (p>0.05). Mean central macular thickness values were significantly higher in LTFC (p=0,012) and TTFC groups (p=0,0419) at 1 month of follow-up. There was no significant increase in mean central macular thickness values from baseline in all groups (p>0.05) after 6 months and no significant differences among the groups (p>0.05) during follow-up. At baseline, mean IOP was significantly lower in control group (p=0,0000). All fixed-combinations significantly reduced IOP in all follow-up visits, with similar lowering effect (p=0,816). These findings indicate that the use of prostaglandin analogues and timolol fixed-combinations didn't significantly increased mean flare values or mean central macular thicknes measurements after 6 months of follow-up in this population / Mestrado / Oftalmologia / Mestra em Ciências Médicas
62

Curva diária e valores da pressão intraocular obtidos com tonômetro de rebote em equinos hígidos da raça crioula (Equus caballus)

Bacchin, Angela Beatriz de Oliveira January 2018 (has links)
A tonometria é de extrema importância durante o exame oftálmico, pois auxilia no diagnóstico e no acompanhamento do glaucoma e de inflamações intraoculares. No entanto, os valores da pressão intraocular podem sofrer influência do momento do dia em que o exame é realizado. Objetivou-se avaliar a pressão intraocular (PIO) com tonômetro de rebote em equinos hígidos da raça Crioula em diferentes horários do dia. Foram avaliados ambos os olhos de 25 cavalos da raça Crioula, machos ou fêmeas, subdivididos em três categorias de diferentes idades designadas por GI: nove animais (3-5 anos de idade), GII: oito animais (6-8 anos de idade) e GIII: oito animais (9-16 anos de idade). Previamente à tonometria foram realizados teste lacrimal de Schirmer, biomicroscopia com lâmpada de fenda, prova da fluoresceína e oftalmoscopia indireta em todos os equinos. Num mesmo dia foram realizadas sete aferições da PIO (às 6, 9, 12, 15, 18, 21 e 24 horas). A avaliação estatística utilizou o teste T de Student quando haviam dois grupos de comparações, e o teste de análise de variância (ANOVA) para as variáveis PIO, horário de aferição (tempo) e categoria de idade. O valor médio da pressão intraocular obtido foi de 28,4±3,7 mmHg considerando todos os animais avaliados. Os valores médios da pressão intraocular para os equinos de GI, GII e GIII foram 29,2±3,5 mmHg, 28,4±4,3 mmHg e 27,7±3,2 mmHg, respectivamente. Não houve diferença estatisticamente significativa entre os olhos direito e esquerdo (p= 0,257), nem entre sexos (p= 0,284). Quando comparadas as idades, a PIO média foi significativamente maior nos indivíduos jovens (p= 0,012). Não houve diferença estatisticamente significativa entre os diferentes horários do dia (p= 0,560). Os valores da PIO aferidos com o tonômetro de rebote em equinos da raça Crioula sofreram influência da idade. Os valores da pressão intraocular média obtidos com tonômetro de rebote em equinos hígidos não variaram em diferentes horários ao longo do dia. / The tonometry is extremely important during ophthalmic examination, because assists in the diagnosis and follow-up of glaucoma and intraocular inflammation. However, intraocular pressure values may be influenced by the moment of the day it is measured. The objective was to evaluate the intraocular pressure (IOP) with Rebound Tonometer in healthy horses of the Crioula breed at different times of the day. Twenty five horses, male or female, were divided into three groups by age: Group I: nine horses (3-5 years old), Group II: eight horses (6-8 years old), and Group III: eight horses (9-16 years old). Ophthalmic examination was performed previously by Schirmer Tear Test, slit lamp biomicroscopy, fluorescein test and indirect ophthalmoscopy in all horses. Seven measurements of intraocular pressure were assessed on the same day (at 6, 9, 12, 15, 18, 21 and 24 hours).The Student’s T Test statistical analysis was used when there was two groups of comparisons, and the Analysis of Variance (ANOVA) was used for variables IOP, measurement time and age category. The average value of intraocular pressure was 28.4 ± 3.7 mmHg considering all the animals evaluated. The mean intraocular pressure for groups I, II and III were 29.2 ± 3.5 mmHg, 28.4 ± 4.3 mmHg and 27.7 ± 3.2 mmHg, respectively. There was no statistically significant difference between right and left eyes (p = 0.257), nor between genders (p = 0.284). When compared to the ages, the average IOP was significantly higher in young animals (p = 0.012). There was no statistically significant result between the different times of the day (p = 0.560). The IOP values measured with rebound tonometer in Crioula horses were influenced by age. The average intraocular pressure values obtained with rebound tonometer in healthy horses did not change with time of day.
63

The Role of the Vasculature and Immune System in Models of Glaucoma

Sabljic, Thomas F. 18 November 2016 (has links)
Purpose: The purpose of this study was to investigate the role of the vasculature and immune system in models of glaucoma. Vascular changes have been implicated in glaucoma. As well there is mounting evidence that the immune system plays a role in the disease. It is my hypothesis that the vasculature and immune system play a role in the retinal response to injury in models of glaucoma. Methods: Immunohistochemistry, in vivo retinal imaging (Bright field, fluorescent, optical coherence tomography), Slit2 injections and Evan’s blue labeling were used to investigate vascular and immune changes associated with retinal ganglion cell death after optic nerve crush up to 28 days after injury. Histology, immunohistochemistry, and intravascular labeling were utilized to investigate the role of the vascular degeneration and the systemic immune response to elevated intraocular pressure in 8-16 week old AP-2β Neural Crest Cell Knockout (AP-2β NCC KO) mice. Results: The vascular and immune responses to optic nerve crush were not found to play a significant role in the response to retinal ganglion cell death. Conversely the role of vascular degeneration and immune cell recruitment to the retinas of AP-2β NCC KO mice demonstrated that these factors played a significant role in the retinal response to injury. Conclusion: The vasculature and immune system play a varied role in the response to retinal injury and neurodegeneration depending on the model being studied. The vascular and immune changes were of minimal significance in acute optic nerve crush injury. On the other hand, the chronic injury associated with elevated intraocular pressure in AP-2β NCC KO mice was associated with significant vascular degeneration and systemic immune cell infiltration. / Thesis / Doctor of Philosophy (PhD)
64

Multidisciplinary Engineered Approaches to Investigate Human Trabecular Meshwork Endothelial Cells in Regulation of Intraocular Pressure

Kim, Bongsu January 2011 (has links)
No description available.
65

Progression of retinal ganglion cell loss observed as a result of anterior segment dysgenesis following conditional deletion of activating protein-2 in cranial neural crest cells

Saraco, Anthony January 2019 (has links)
Our lab has shown that conditionally disrupting the tcfap2beta gene, responsible for the activating protein-2beta (AP-2beta) transcription factor, exclusively in the craniofacial neural crest cells, leads to anterior segment dysgenesis. Subsequent loss of the corneal endothelium results in the adherence of the iris to the corneal stroma, causing closure of the iridocorneal angle. The activating protein-2beta neural crest cell knockout (AP-2beta NCC KO) model involves a complete blockage of the both the conventional (through the trabecular meshwork) and non-conventional (uveoscleral) pathways for aqueous humor drainage, and therefore it could be used as a powerful experimental model for glaucoma. As shown by our previous work, elevated intraocular pressure (IOP) and a 35% decrease in the number of cells in the retinal ganglion cell (RGC) layer was observed in AP-2beta NCC KO mice by 2 months; 6 to 11 months sooner than other reported mouse models of glaucoma. These observations suggested that the AP-2beta NCC KO mouse could be a novel and cost-effective experimental model for glaucoma if the RGC loss occurred progressively rather than due to a congenital defect. The purpose of this research project was to investigate how the retinal ganglion cell layer and macroglial activity changes with respect to age in the AP-2beta NCC KO mutant through immunofluorescence. Specifically, it was investigated whether the loss of RGCs was progressive and due to the increased IOP caused by the blockage of the uveoscleral drainage pathway. A significant decrease in the number of RGCs was observed between P4 and P10 in the retinal periphery of both WT and AP-2beta NCC KO mice (p<0.05), which is indicative of the programmed cell death that occurs due to retinal pruning during development. No statistical difference between WT and AP-2beta NCC KO mice phenotypes was observed at postnatal day 4 (P4), suggesting that no developmental defect resulted in the significant loss of RGCs at 2 months. In all other time points investigated, while no statistical difference was found between WT and the AP-2 NCC KO mutant, a clear downward trend was present in the AP-2 NCC KO mutant retinal ganglion cell layer from P10 to P40. There was also an expression of glial fibrillary acidic protein (GFAP) by Müller cells, indicating the presence of neuroinflammation at P35 and P40. This substantiates the potential P42 starting point of neurodegeneration our lab previously observed. This was further corroborated with Müller cell-associated expression of GFAP at P35 and P40 exclusively in the AP-2beta NCC KO mouse. Overall, we have shown that the retinal damage observed in our AP-2beta NCC KO mouse is not due to a developmental defect, but rather occurs over time. Thus, this mouse model, which appears to block both the conventional and unconventional uveoscleral pathways, has a profound effect on aqueous humor drainage. As a result, the model requires relatively little time to observe an increase in IOP and subsequent RGC loss. Our findings suggest that the AP-2beta NCC KO mouse can be a novel, powerful, and extremely cost-effective experimental model for glaucoma. / Thesis / Master of Science (MSc)
66

The effects of Nd:YAG laser cyclophotocoagulation on corneal sensitivity, intraocular pressure, aqueous tear production and corneal nerve morphology in the canine eye

Weigt, Anne Kelley 26 June 2001 (has links)
Corneal ulceration with prolonged healing following Nd:YAG laser cyclophotocoagulation in dogs is a frequent complication. It is hypothesized that these corneal ulcerations may be a form of neurotrophic keratitis due to laser-induced damage to corneal innervation. Fifteen clinically normal dogs had the neodymium:yttrium aluminum garnet(Nd:YAG) laser cyclophotocoagulation performed on the left eye. Each treated eye received 100 Joules of laser energy. Corneal touch threshold (CTT) and Schirmer I tear tests (STT) were performed before the surgery and on days 1,3,5,7,9,11, and 13 post-laser treatment. Applanation tonometry was performed before surgery and twice daily for 14 days post-laser treatment. Eyes were enucleated after 14 days and corneal nerves were stained using a gold chloride technique. Major nerve bundles entering the cornea were quantitated by quadrant, using camera lucida reproductions. Nerve bundle diameters were measured using NIH image computer software on computer-scanned images. Statistical methods included repeated values for analysis of variance for CTT, STT and IOP, and a paired t-test for nerve diameters and bundles. All laser treated eyes had significantly higher CTTs (P<0.05) compared to control eyes for all measurements. Six out of fifteen dogs had evidence of ulcerative keratitis. Intraocular pressure was significantly lower in laser treated eyes compared to control eyes in the a.m. on days 2-9,and 14, and in the p.m. on days 2-11 using a Bonferroni-corrected alpha level (P<0.0039). A significant decrease of one nerve bundle per corneal quadrant was found between the laser treated and control eyes. There was no significant difference in STT or nerve bundle diameters between laser treated and control eyes. Nd:YAG laser cyclophotocoagulation effectively reduces IOP while increasing CTT. The procedure also causes a significant decrease in the number of major nerve bundles entering the cornea, but has no effect on the diameter of those bundles. These findings support the hypothesis that nerve damage and corneal hypoesthesia are etiologic factors in ulcerative keratitis following Nd:YAG laser cyclophotocoagulation. / Master of Science
67

Curva diária de pressão intraocular em porquinhos da índia (Cavia porcellus) de diferentes faixas etárias com tonometria de rebote

Ghiggi, Eduardo January 2016 (has links)
A aferição da pressão intraocular (PIO) é essencial para o exame oftálmico. Objetivou-se estabelecer os valores da curva diária da PIO de porquinhos da índia de diferentes faixas etárias com tonômetro de rebote. A PIO foi aferida às 6, 12, 18 e 24 horas utilizando o tonômetro de rebote (Tonovet®). Os porquinhos da índia foram subdivididos em dois grupos com 10 animais no grupo I e 4 animais no grupo II, considerando as idades, designados por GI (animais entre 2 a 3 meses de idade) e GII (animais entre 2 a 3 anos de idade). Previamente, foram realizados teste da lágrima de Schirmer, prova da fluoresceína, biomicroscopia com lâmpada de fenda e oftalmoscopia indireta em todos animais. O valor médio da pressão intraocular foi de 12,0 ± 1,83 mmHg. Foram encontradas diferenças significativas entres as idades, sendo que os valores médios para o grupo I foram 11,63 ± 0,29 mmHg, e para o grupo II foram 12,82 ± 0,45mmHg (P= 0,0295). Não foram encontradas diferenças entre ambos os olhos (P= 0,7454). Não foram encontradas diferenças significativas nos valores da PIO relacionadas ao sexo (P= 0,1858). Os valores da PIO em porquinhos da índia tiveram alteração nas horas avaliadas. Com base nos resultados obtidos foi possível concluir que os valores da PIO em porquinhos da índia da sofrem alterações ao longo do dia. Os menores valores de pressão intraocular ocorreram às 18 horas. / The measuring of intraocular pressure (IOP) it is essential for the ophthalmic evaluation; the aim of this study was establish the values of the IOP diurnal curve of guinea pigs with different ages using the rebound tonometer (Tonovet®). The animals were divided according to the age in two groups, Group I (GI) constituted with 10 guinea pigs aged between 2 -3 moths, and Group II (GII), 4 animals with 2 -3 years of old. Previously the Schirmer tear test, fluorescein test, biomicroscopy with slit lamp, and direct optalmoscopy were performed on all animals. The men value of IOP was 12.0±0.34 mmHg. Statistical difference were found between ages (mean GI 11.64 ± 0.29 mmHg, and GII 12.83 ± 0.45mmHg), did not have statistical difference related with gender (P= 0.1858) or between eyes (P= 0.7454). In conclusion the guinea pigs had alteration of IOP true the day, the values of IOP are higher in the morning period, decrease true the day and at the night period haves an elevation again.
68

Estudo sobre a deformação da córnea utilizando o sistema de tonometria de não contato integrado a uma câmera de Scheimpflug em olhos saudáveis / Evaluation of corneal deformation analyzed with non-contact tonometer system integrated with an ultra-high-speed (UHS) Scheimpflug camera in healthy eyes

Valbon, Bruno de Freitas 23 September 2016 (has links)
OBJETIVOS: 1) Avaliar os parâmetros de biomecânica ocular provenientes do Corvis ST (Oculus Corvis ST, Scheimpflug Technology; Wetzlar, Germany) obtidos de olhos saudáveis de uma população de pacientes brasileiros. 2) Correlacionar os parâmetros derivados do Corvis ST com a idade de pacientes jovens saudáveis. 3) Verificar se as técnicas de facoemulsificação (FC) e do laser de femtosegundo (LFS), empregadas na correção cirúrgica de catatara, influenciam os parâmetros de biomecânica ocular provenientes do Corvis ST. 4) Analisar as alterações da deformação da córnea observadas em um caso de ectasia pós LASIK com flap espesso. MÉTODOS: 1) Estudo clínico transversal conduzido em 90 pacientes (90 olhos saudáveis). Foram avaliados 11 parâmetros derivados do sistema de tonometria de não contato integrado com a câmera ultrarrápida de Scheimpflug (Oculus Corvis ST, Scheimpflug Technology; Wetzlar, Germany), a saber: deformidade de amplitude (DA); pressão intraocular; 1st A time; tempo de concavidade máxima; 2nd A time; 1st A Length (tempo da primeira aplanação); 2nd A Length (tempo da segunda aplanação); raio de curvatura de maior alcance; raio de curvatura normal; velocidade de entrada (Vin) e de saída (Vout). Estes parâmetros foram correlacionados com a espessura central corneana mensurada pela Tomografia de Córnea e Segmento Anterior (Pentacam® - Oculus, Wetzlar, Germany). 2) Estudo clínico observacional, retrospectivo, conduzido em 89 pacientes (89 olhos saudáveis). Os parâmetros derivados do Corvis ST foram correlacionados com a idade dos pacientes. 3) Estudo clínico prospectivo, envolvendo 151 olhos de 127 pacientes com diagnóstico de catarata nuclear. Setenta e cinco olhos de 65 pacientes foram submetidos à técnica do laser de femtosegundo (AlconLenSx, Aliso Viejo, USA) e 76 olhos de 62 pacientes à facoemulsificação convencional (Alcon Infinit, Fort Worth, USA). Foram avaliados os 11 parâmetros de biomecânica ocular derivados do Corvis ST antes (Pré) e após as cirurgias de catarata (D1, primeiro dia de pósoperatório). A densitometria do cristalino (scattering) foi realizada pelo PNS (Pentacam Nucleus Staging). 4) Avaliação com tomografia de coerência óptica de espessura dos flaps corneanos pós Lasik e análise dos parâmetros biomecânicos provenientes do Corvis ST em uma córnea com ectasia pós Lasik. RESULTADOS: 1) A média de idade dos pacientes foi de 35,80 ± 12,83 anos. A média do equivalente esférico foi de -3,29 ± 3,69 dioptrias. A média da espessura central corneana foi de 547,50 ± 32,00 ?m Os valores dos 11 parâmetros biomecânicos obtidos de olhos saudáveis, foram os seguintes: deformidade de amplitude 1,05 ± 0,08 mm; tempo de concavidade máxima 18,38 ± 0,93 ms; pressão intraocular 16,43 ± 2,15 mmHg; tempo da primeira aplanação (1st A time) 8,32 ± 0,33 ms; tempo da segunda aplanação 23,80 ± 0,44 ms; raio de curvatura de maior alcance 11,09 ± 2,06 mm; raio de curvatura normal 7,59 ± 0,67 mm; tempo da primeira aplanação (1st A Length) 2,07 ± 0,38 mm; tempo da segunda aplanação (2nd A Length) 2,37 ± 0,47 mm; velocidade de entrada (Vin) 0,21 ± 0,05 m/s e velocidade de saída (Vout) -0,33 ± 0,07 m/s. 2) A média de idade dos pacientes foi de 27,50 ± 6,30 anos. O tempo de concavidade máxima alcançada da córnea (HC-time) foi o único dos 11 parâmetros que apresentou correlação significativa com a idade (p=0,04, rs=0,18). 3) A média de idade dos pacientes dos grupos LFS (laser de femtosegundo) e FC (facoemulsificação convencional) foram, respectivamente, 67,6 ± 9,9 anos e 68,4 ± 11,8 anos. No grupo LFS, 9 dos 11 parâmetros foram estatisticamente significativos entre o Pré e D1; e no grupo FC, 7 dos 11 parâmetros foram estatisticamente significativos entre o Pré e D1. Entre os 11 parâmetros biomecânicos avaliados, somente o tempo de concavidade máxima da córnea (HC-time) foi significativamente diferente entre os dois grupos em D1 (p=0,0387). 4) Paciente do sexo feminino, 45 anos, submetida à Lasik em ambos os olhos. Com a utilização da tomografia de coerência óptica (OCT Rtvue, OptoVue, Fremont, CA,USA) foram identificados: um flap com espessura central de 392 ?m no OD e dois cortes, sendo um flap incompleto profundo e o outro mais fino superiormente, no OE. Os parâmetros derivados do Corvis ST como a deformidade de amplitude são diferentes em ambos os olhos. CONCLUSÕES: 1) Os valores de 8 dos 11 parâmetros derivados do Corvis ST foram influenciados pela espessura central da córnea, porém esta influência foi baixa. 2) Em olhos saudáveis de pacientes jovens foi obtida correlação significativa entre a idade e o tempo de concavidade máxima, que é o tempo do início de aplanação até a concavidade máxima alcançada da córnea. 3) O laser de femtosegundo para cirurgia de catarata e a técnica de facoemulsificação convencional induziram alterações nas propriedades biomecânicas da córnea no D1. Dos 11 parâmetros biomecânicos estudados apenas o tempo de concavidade máxima da córnea apresentou diferença significativa entre os grupos (LFS e FC) no D1. 4) A ectasia unilateral após LASIK pode ocorrer devido a flap espesso com falência biomecânica da córnea / PURPOSE: 1) To evaluate ocular biomechanical metrics given by the CorVis ST (Oculus, Inc., Berlin, Germany) in a population of healthy Brazilian patients. 2) To correlate parameters derived from corneal deformation resulting from non-contact tonometry integrated with an ultra-high-speed (UHS) Scheimpflug camera (Oculus Corvis ST, Scheimpflug Technology; Wetzlar, Germany) with age in normal eyes from young patients. 3) To evaluate the changes of corneal biomechanical after femtosecond laser - assisted cataract (FS) and to compare the parameters derived by Corvis ST between standard phacoemulsification (SP) and femtosecond laser - assisted in cataract surgery. 4) To report a case of post-LASIK corneal ectasia due to a thick flap, while the contralateral eye did not develop ectasia after an incomplete deep flap cut, followed by a thinner flap Lasik procedure. METHODS: 1) An observational and cross-sectional study involving 1 eye randomly selected from 90 healthy patients. Studied parameters (including deformation amplitude, first applanation time, highest concavity time, second applanation time, first applanation length, second applanation length, curvature radius highest concavity, curvature radius normal, velocity in, and velocity out) derived from the CorVis ST were correlated to central corneal thickness from the Pentacam (Oculus, Inc.). Differences between data on the basis of gender were evaluated. 2) Observational, retrospective study involving one eye randomly selected from study participants, totaling 89 healthy eyes. The Scheimpflug images were taken with an ultra-high-speed camera during each measurement by the Corvis ST. The deformation amplitude (DA) and other parameters (e.g., pachy apex, intraocular pressure, 1st A time, highest concavity-time, 2nd A time, 1st A Length, 2nd A Length, Wing-Dist, curvature radius highest concavity, curvature radius normal, Vin, Vout) measured by the corvis ST were correlated with age. 3) Prospective study: 151 eyes of 127 patients were underwent cataract surgery. 75 eyes of 65 patients were with femtosecond laser-assisted (FS)(Alcon Len Sx, Aliso Viejo,USA) and 76 eyes of 62 patients with standard phacoemulsification (SP) (Alcon Infinit, FortWorth, USA). 4) Case Report. RESULTS: 1) About the first study: Mean patient age was 35.80 ± 12.83 years (range: 21.07 to 78.84 years). Mean central corneal thickness was 547.50 ± 32.00 ?m (range: 490 to 647 ?m) and mean spherical equivalent refraction was -3.29 ± 3.69 diopters (range: -9.50 to +10.37 diopters). Mean deformation amplitude was 1.05 ± 0.08 mm (range: 0.91 to 1.26 mm). Highest concavity time was 18.38 ± 0.93 ms (range: 16.95 to 21.07 ms). Intraocular pressure was 16.43 ± 2.15 mm Hg (range: 11.50 to 21.0 mm Hg). First applanation time was 8.32 ± 0.33 ms (range: 7.53 to 9.12 ms) and second applanation time was 23.80 ± 0.44 ms (range: 22.76 to 24.95 ms). First applanation length (max) was 2.07 ± 0.38 mm (range: 1.20 to 3.10 mm) and second applanation length (max) was 2.37 ± 0.47 mm (range: 1.33 to 4.12 mm). Curvature radius highest concavity was 11.09 ± 2.06 mm (range: 7.58 to 15.98 mm) and curvature radius normal was 7.59 ± 0.67 mm (range: 6.82 to 11.02 mm). Velocity in was 0.21 ± 0.05 m/s (range: 0.16 to 0.72 m/s) and velocity out was -0.33 ± 0.07 m/s (range: - 0.72 to -0.20 m/s). Studied parameters were not associated with gender. 2) Mean patient age was 27.50 ± 6.30 years. The highest concavity-time was the only studied parameter statistically significantly correlated to age (i.e., p=0.04, rs=0.18). 3) In relation the surgery of cataract: In group of FS, 9 of 11 parameters derived from Corvis ST were statistically significant (ss). In group of SP, 7 of 11 parameters derived from Corvis ST were ss. Only the HC - time was statistically significant between two groups (FS;SP) with p = 0.0387. 4) Corneal OCT identified a deep meniscos-shaped Lasik flap, with a central thickness of a 392 ?m in the right eye, and a incomplete deep peripheral cut in the left eye with a thinner meniscos-shaped LASIK flap. CONCLUSIONS: 1) Eight of 11 ocular biomechanical metrics given by the CorVis ST were associated with central corneal thickness, but the influence of central corneal thickness on these measurements was low. 2) In healthy eyes, age and pressure or biomechanics as derived from the Corvis ST parameters were not associated with exception to highestconcavity-time, i.e., the time from starting until the highest concavity is reached. 3) The use of the femtosecond laser- assisted system for cataract surgery and standard phacoemulsification induzed changes of biomechanical properties of the cornea by Corvis ST. Only 1 of 11 parameters studied was different statistically in two groups. 4) Unilateral ectasia after LASIK may occur due to a thick flap which leads to biomechanical failure of the cornea
69

Mittelfristiger Einfluss der Vitrektomie bei Makulaerkrankungen auf den Augeninnendruck / Medium-term influence of pars plana vitrectomy on intraocular pressure

Gebest, Julia 24 January 2019 (has links)
No description available.
70

Die Auswirkungen Ketamin-basierter Narkoseprotokolle auf den intraokularen Druck bei der Katze – eine prospektive randomisierte Blindstudie

McIntosh, Jenny 12 June 2013 (has links) (PDF)
Der Einsatz von Ketamin erfolgt in der Humananästhesie, vor allem aufgrund seiner vielfältigen Nebenwirkungen, nur noch nach strenger Indikation. In der Veterinärmedizin ist Ketamin tierartenübergreifend für die Injektionsnarkose weit verbreitet. Um den bekannten Nebenwirkungen vorzubeugen, wird Ketamin mit verschiedenen anderen Anästhetika kombiniert und stellt so ein sicheres Narkoseverfahren bei Tieren dar. Eine besondere Herausforderung ist die Anästhesie bei ophthalmologischen Patienten unter Berücksich-tigung der Kontrolle des Intraokularen Drucks (IOP). In diesem Zusammenhang gibt es in der Literatur widersprüchliche Angaben zur Auswirkung von Ketamin auf den IOP beim Menschen und verschiedenen Tierarten. Auch für die Auswirkungen von Propofol und der endotrachealen Intubation auf den IOP existieren widersprüchliche Aussagen. In der vorliegenden Arbeit wurde untersucht, ob gängige Ketamin-Kombinationsnarkosen bei der augengesunden Katze einen Einfluss auf den IOP haben. Angeregt durch Berichte in der Literatur wurde zudem untersucht, ob die Applikation von Propofol sowie die endotracheale Intubation den IOP bei der Katze beeinflussen. Methodik: Untersucht wurden 48 adulte, augengesunde Katzen, die dem chirurgischen Patientengut der Klinik für Kleintiere der Universität Leipzig entstammten. Es handelt sich um eine prospektive, randomisierte Blindstudie. Die Patienten wurden vier Untersuchungsgruppen zugeordnet. Zur intramuskulären Narkoseeinleitung erhielten Tiere der KX-Gruppe Ketamin (10 mg/kg) und Xylazin (1 mg/kg), der KXAtr-Gruppe Ketamin (10 mg/kg), Xylazin (1 mg/kg) und Atropin (0,025 mg/kg), der KA-Gruppe Ketamin (20 mg/kg) und Acepromazin (0,5 mg/kg) und der KM-Gruppe Ketamin (10 mg/kg) und Medetomidin (50 g/kg). Bei allen Patienten wurde mittels Tono-Pen® XL zu verschiedenen Zeitpunkten der IOP bestimmt: vor Narkoseeinleitung (Ausgangswert), nach Narkoseeinleitung nach 5, Zusammenfassung 86 10, 15 und 20 Minuten und direkt nach der Intubation sowie final nach Beendigung der Narkose während der Aufwachphase. Einige Tiere erhielten zur Vertiefung der Narkose vor der Intubation Propofol. Im Anschluss erfolgte eine ophthalmologische Untersuchung der Patienten, um eine Augenerkrankung auszuschließen. Ergebnisse: Der mittlere Ausgangs-IOP aller Tiere beträgt 15,8 mmHg. Mit p = 0,756 besteht kein signifikanter Unterschied zwischen den Gruppen. Getrennt nach linken (OS) und rechten (OD) Augen ist der mittlere IOP 15,7 und 15,8 mmHg. Dieser Unterschied ist nicht signifikant (p = 0,442). Daher wird für die Auswertung der Mittelwert aller 6 Datenpunkte pro Tier und Messzeitpunkt zugrunde gelegt. Im Vergleich zum Ausgangswert zeigt die KX-Gruppe keine signifikanten IOP-Änderungen. Die KXAtr-Gruppe und die KM-Gruppe weisen zur Final-Messung einen signifikanten IOP-Abfall um 16 % (p = 0,012) bzw. 17 % (p = 0,021) im Vergleich zum Ausgangswert auf. Die KA-Gruppe zeigt zur 15-Minuten-Messung den stärksten IOP-Abfall mit 21 % Prozent (p = 0,001) gegenüber dem Ausgangswert. Ab der 10-Minuten-Messung bis zur post-Intubations-Messung ist der IOP-Abfall der KA-Gruppe signifikant. Für die Gesamtstichprobe hat die Intubation keinen signifikanten Einfluss auf den IOP (p = 0,063). Die Gabe von Propofol zur Vertiefung der Narkose bei einzelnen Tieren hat ebenfalls keinen signifikanten Einfluss auf den IOP (p = 0,42). Schlussfolgerung: Die verwendeten Ketamin-basierten Narkoseprotokolle bewirken bei der augengesunden Katze keinen signifikanten IOP-Anstieg. Die Gruppen KX, KXAtr und KM gewährleisten für den Zeitraum von 20 Minuten nach Narkoseeinleitung einen relativ stabilen IOP. Trotz des signifikanten IOP-Abfalls in der KA-Gruppe sind sämtliche IOP-Schwankungen aller Gruppen klinisch nicht relevant. Die gemessenen IOP-Werte bewegen sich alle im physiologischen Bereich. Zudem geben die Ergebnisse keinen Hinweis auf eine IOP-Steigerung infolge Propofolgabe und Intubation bei der Katze. / Ketamine is used in human medicine based on strict indications, mainly due to its numerous side effects. In veterinary medicine however Ketamine is commonly used to induce anesthesia intramuscularly throughout all species. To minimize the well known side effects Ketamine is used in combination with several other anesthetics and thus represents a safe anesthetic procedure in animals. Ophthalmological patients are a particular challenge for anesthetists with regard to maintaining the intraocular pressure (IOP). Conflicting data can be found in the literature about the effects of Ketamine on IOP in humans and various animal species. The literature also contains various statements about the effects of Propofol and endotracheal intubation on IOP. In this clinical trial we investigated the effects of commonly used Ketamine-based anesthetic protocols on IOP in cats. Motivated by conflicting statements in the literature the analysis of the effects of Propofol and endotracheal intubation on IOP was included in the study. Methods: This is a prospective, randomized, blinded study. 48 adult cats without ophthalmological abnormalities, recruited from the pool of admitted surgical patients of the Department of Small Animal Medicine of the University of Leipzig were included in the study. The patients were assigned to one of the following four groups and anesthesia was induced intramuscularly. Cats in the KX-group were induced with Ketamine (10 mg/kg) and Xylazine (1 mg/kg). Cats in the KXAtr-group were induced with Ketamine (10 mg/kg), Xylazine (1 mg/kg) and Atropine (0,025 mg/kg). Cats in the KA-group were induced with Ketamine (20 mg/kg) and Acepromazine (0,5 mg/kg). Cats in the KM-group were induced with Ketamine (10 mg/kg) and Medetomidine (50 g/kg). In all patients the IOP was measured three times per eye using the Tono-Pen® XL at particular times: baseline IOP before induction of anesthesia, at 5, 10, 15 and 20 minutes after induction of anesthesia, after intubation and final IOP after completion of surgery. Some cats received a single bolus of Propofol to be able to tolerate endotracheal intubation. After the final IOP-measurement all Zusammenfassung 88 cats were subjected to an ophthalmological examination, including slitlamp biomicroscopy and gonioscopy, in order to exclude patients with ophthalmological pathologies. Results: The mean baseline IOP for all animals is 15,8 mmHg (SD 4,0). There is no significant difference between the four groups (p = 0,756). The mean IOP for the right (OD) and left eyes (OS) of all patients was 15,8 mmHg and 15,7 mmHg, respectively. There is no significant difference between right (OD) and left eyes (OS) (p = 0,442). Therefore all further analyses are based on the mean of all six data points per animal and measuring time. The KX-group shows no significant IOP-change relative to baseline-IOP. The KXAtr and KM-group show a significant decrease in IOP of 16 % and 17 %, respectively, at the final measurement compared with baseline-IOP. The KA-group shows a significant decrease in IOP starting at 10 minutes after induction of anesthesia until the post-intubation measurement. The maximum decrease in IOP in this group is 21 % relative to baseline-IOP 15 minutes after induction of anesthesia. For the total data no significant influence of endotracheal intubation on IOP could be detected (p = 0,063). The application of Propofol in a total of 14 cats has no significant effect on IOP (p = 0,42). Conclusion: The Ketamine-based anesthetic protocols used in this study do not cause a significant increase in IOP in cats without ophthalmological abnormalities. The KX, KXAtr and KM-group ensure a relatively stable IOP for the time period of 20 minutes after induction of anesthesia. Despite the significant IOP-decrease in the KA-group none of the IOP-changes in all groups examined are of clinical relevance. All of the collected IOP-values are within the physiological range for cats. There is no evidence for an increase in IOP caused by endotracheal intubation or the application of Propofol.

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