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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.
41

Anestesia peribulbar guiada por ultrassom com diferentes volumes de ropivacaína a 1 por cento associada ou não ao bicarbonato de sódio em cães / Anesthesia peribulbar guided by ultrasound with ropivacaine 1 percent in different volumes associated or not with sodium bicarbonate in dogs

Wagatsuma, Juliana Tessália [UNESP] 08 August 2016 (has links)
Submitted by JULIANA TESSÁLIA WAGATSUMA null (jutessalia@yahoo.com.br) on 2016-09-16T18:40:05Z No. of bitstreams: 1 tese banco unesp.pdf: 1884895 bytes, checksum: 6191e5a465fbd78f3ca1dd64c9983f46 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-16T20:19:27Z (GMT) No. of bitstreams: 1 wagatsuma_jt_dr_araca.pdf: 1884895 bytes, checksum: 6191e5a465fbd78f3ca1dd64c9983f46 (MD5) / Made available in DSpace on 2016-09-16T20:19:27Z (GMT). No. of bitstreams: 1 wagatsuma_jt_dr_araca.pdf: 1884895 bytes, checksum: 6191e5a465fbd78f3ca1dd64c9983f46 (MD5) Previous issue date: 2016-08-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Sete cães foram submetidos à anestesia inalatória com isoflurano para permitir a realização do bloqueio peribulbar, com punção única inferior, guiado por ultrassonografia com ropivacaína a 1%, e assim comprovar a eficácia desta técnica de bloqueio guiado na redução do volume anestésico injetado de ropivacaína a 1%, e avaliar possíveis efeitos potencializadores como a redução da latência e do volume anestésico utilizado, assim como complicações oftálmicas associadas à alcalinização do anestésico com bicarbonato de sódio a 0,33%. Foram avaliados dois volumes diferentes de ropivacaína a 1% (0,2 mL/Kg e 0,1 mL/Kg) associados ou não ao bicarbonato de sódio a 0,33% que, ao ser adicionado ao anestésico, elevou o pH da solução anestésica para 6,0. Uma vez realizado o bloqueio peribulbar, com punção única inferior, guiado por ultrassom o tempo necessário para ocorrer a centralização do bulbo do olho era cronometrado, e os animais permaneciam anestesiados para a aferição da pressão intraocular, que foi realizada imediatamente e 15 minutos após o bloqueio e, concluída essa mensuração, a anestesia foi encerrada. Com os cães já despertos foram avaliados os seguintes parâmetros: a pressão intraocular, o diâmetro pupilar, o bloqueio motor, sensitivo (realizado por meio de estesiometria corneal com estesiômetro de Cochet e Bonnet), e a observação das intercorrências oftálmicas como quemose, hiperemia conjuntival, hematoma subconjuntival, prurido e secreção ocular. As análises estatísticas foram conduzidas com o auxílio do software de livre acesso RStudio. Variáveis não paramétricas, ordinais e categóricas foram avaliadas por teste estatística tipo ANOVA ou ATS. Variáveis contínuas paramétricas foram avaliadas pelo Modelo linear misto para medidas repetidas. O Teste Kendall Tau-b foi utilizado para verificar possíveis correlações entre as variáveis. Com exceção do reflexo fotomotor (G0,1: 30 (0-90) e G0,2: 150 (0-210 minutos), não houve diferença significativa entre grupos quando comparado a latência, a pressão intraocular, o diâmetro pupilar, as durações e qualidade dos bloqueios motor e sensitivo, e as intercorrências oftálmicas, mas houve diferença significativa quando comparados os momentos dentro de um mesmo grupo para todas as variáveis analisadas. Deste modo concluiu-se que entre os volumes avaliados de ropivacaína a 1%, no bloqueio peribulbar guiado por US em cães, houve um melhor desempenho clínico relacionado a intensidade e duração dos bloqueios sensitivo e motor, com o volume de 0,2 mL/kg. A adição de NaHCO3 - a 0,33% não agregou benefícios, como a potencialização da ação ou redução da latência anestésica, contudo não ocorreram intercorrências oftálmicas significativas relacionadas diretamente à sua administração ou a da ropivacaína a 1%. / Seven dogs were subjected to inhalation anesthesia with isoflurane to allow the realization of peribulbar block, with lower single puncture, guided by ultrasound with 1% ropivacaine, and thus prove the effectiveness of this blocking technique guided in reducing anesthetic volume of ropivacaine 1%, and evaluate possible potentiating effects such as reducing the latency and anesthetic volume used and ophthalmic complications associated with the anesthetic alkalinization with sodium bicarbonate 0,33%. We evaluated two different volumes of 1% ropivacaine (0.2 ml / kg and 0.1 ml / kg) with or without sodium bicarbonate to 0.33% which when added to anesthetic raised the pH of the solution anesthetic to 6.0. Once performed peribulbar block, with lower single puncture guided by ultrasound time required to place the centralization of the eye bulb was timed, and the animals remained anesthetized for the measurement of intraocular pressure was carried out immediately and 15 minutes after blockade and completed this measurement, anesthesia was terminated. With dogs the following parameters already awake were evaluated intraocular pressure, pupil size, the duration and intensity of motor block, sensory (performed by esthesiometry corneal with esthesiometer Cochet and Bonnet), and observation of ophthalmic complications as chemosis, conjunctival hyperemia, subconjunctival hematoma, pruritus, and ocular secretion resulting from the anesthetic technique or employee drug. Statistical analyzes were conducted with the free software Rstudio. nonparametric variables, ordinal variables and categorical variables were evaluated using the statistical test ANOVA type or ATS. Parametric continuous variables were assessed by linear mixed model for repeated measures. The Test Kendall Tau-b was used to verify possible correlations between variables. Aside from fotomotor reflex (G0,1: 30 (0-90) and G0,2: 150 (0-210 minutes), there was no significant difference between groups when compared to latency, intraocular pressure, pupil size, the durations and quality of sensory and motor block, and ophthalmic complications, but there was significant difference when comparing times within the same group for all variables. Thus it was concluded that among the evaluated volumes of 1% ropivacaine in the lock US peribulbar guided in dogs, there was a better clinical performance related to the intensity and duration of sensory and motor block, with a volume of 0.2 ml / kg. the addition of 0.33% NaHCO3 no added benefits, such as potentiation of action or reduction of latency anesthetic, but no significant ophthalmic complications directly related to its administration or the 1% ropivacaine. / FAPESP: 2014/09654-6
42

Avaliação da pressão intraocular em chinchilas (chinchilla Lanigera) de diferentes faixas etárias utilizando tonometria de rebote

Claros Chacaltana, Flor Diana Yokoay January 2013 (has links)
A aferição da pressão intraocular (PIO) é fundamental durante o exame oftálmico. Objetivou-se estabelecer os valores de referência da PIO de chinchilas de diferentes faixas etárias utilizando o tonômetro de rebote. A PIO foi aferida ao longo do dia às 7, 12 e 19 horas utilizando o tonômetro de rebote (Tonovet®). As chinchilas foram subdivididas em três grupos com 12 animais cada, considerando as idades, designados por GI (animais com idade entre dois a seis meses), GII (com idade entre 20 e 34 meses) e GIII (animais com idade entre 37 e 135 meses). Previamente, foram realizados teste da lágrima de Schirmer, prova da fluoresceína, biomicroscopia com lâmpada de fenda e oftalmoscopia indireta em todos os animais. O valor médio da pressão intraocular encontrado foi 2,49 ± 0,56 mmHg, os valores médios para o grupo I foi de 2,47±0,581 mmHg, no grupo II de 2,47±0,581 mmHg e no grupo III de 2,51±0,531 mmHg. Não foram encontradas diferenças significativas entre a idade e a PIO (P = 0,756). Não foram encontradas diferenças significativas entre as horas do dia e a PIO (P = 0,415). Não foram encontradas diferenças significativas entre os sexos (P = 0,857). Os valores da PIO em chinchilas não sofrem alterações decorrentes do sexo e da idade dos animais. Não ocorre influência do ritmo circadiano na PIO de chinchilas. / The assessment of intraocular pressure (IOP) is essential for the ocular examination. The purpose of this study was to establish reference values of intraocular pressure chinchillas (Chinchilla lanigera) of different age groups. Thirty-six Chinchillas were divided in three groups of 12 animals each, considering the ages designated by GI (animals aged two to six months), GII (aged between 20 and 34 months) and GIII (animals aged between 37 and 135 months). Intraocular pressure was measured at 7, 12 and 19 hours. Tear production was measured, fluorescein test, slit-lamp biomicroscopy and indirect ophthalmoscopy in all animals and IOP was measured using the rebound tonometer (Tono Vet®) set on the P (undefined species) setting, with measurements obtained from each eye. No abnormalities were found on ophthalmic examination. The mean (±SD) of IOP was 2.49 ± 0.56 mmHg, with a range of 2-4 mmHg. The mean (±SD) of IOP for group I, II and III were 2.47 ± 0.581 mmHg, 2.47 ± 0.581 mmHg and 2,51 ± 0.531 mmHg, respectively. No significant differences were found between age and IOP and no significant differences were found between the hours of day and IOP. No significant differences were found between the genders. The IOP in chinchillas is unchanged between genders and age of the animals. The circadian rhythm is not influenced by IOP in chinchillas.
43

Comparação entre o tonômetro de rebote (Tonovet) e o novo tonômetro de aplanação (Tono-pen a via) durante curva diurna da pressão intraocular de coelhos adultos. / Comparison of a rebound (tonovet) and an new applanation tonometer (tonopen-avia) for diurnal curves of intraocular pressure in adults rabbits

Pereira, Fabiana Quartiero January 2010 (has links)
A determinação da pressão intraocular (PIO) é fundamental no exame oftálmico. Atualmente, novos tonômetros, baseados em diferentes princípios, estão sendo continuamente desenvolvidos. O objetivo deste estudo foi estabelecer os valores de referência da PIO de coelhos adultos, sem efeito de tranquilizantes, mensurada com o tonômetro de rebote (Tonovet) e o de aplanação (Tono-Pen Avia). Também foi preconizada a mensuração da PIO ao longo do dia nesta espécie e a comparação dos resultados obtidos com os dois tonômetros. A PIO foi aferida ao longo do dia (6h, 9h, 12h, 15h e 18h) em 38 coelhos (76 olhos) da raça Nova Zelândia Branca, adultos, com idade média de seis meses, machos ou fêmeas, com massa corporal média de 3,5kg. Previamente, foi realizado teste da lágrima de Schirmer, prova da fluoresceína, biomicroscopia com lâmpada de fenda e oftalmoscopia direta em todos os animais. A tonometria de rebote foi realizada primeiro e, decorridos 10 minutos, foi instilado colírio anestésico e realizada a tonometria de aplanação. A PIO obtida utilizando as duas técnicas foi comparada estatisticamente. A média da PIO com o Tonovet foi de 9,51 ± 2,62 mmHg (variação de 3- 23mmHg) e 15,44 ± 2,16 mmHg (variação de 8 – 26mmHg) com o Tono-Pen Avia. Houve diferença estatística significante entre os valores obtidos com os dois tonômetros (P < 0,001). A relação entre os dois tonômetros foi representada através da equação de regressão linear: y = 0,4923x + 10,754 (y= Tonovet e x= Tono-Pen Avia). No início do dia foram registradas PIOs mais elevadas, mas a média dos valores ao longo do dia, com ambos os aparelhos, foi estatisticamente o mesmo (p = 0,086). O valor do coeficiente de correlação obtido foi r2= 0,357. Os resultados demonstram que o Tono-Pen Avia é mais variável e superestima a PIO de coelhos quando comparado ao Tonovet. Nas primeiras horas do dia, a PIO de coelhos foi mais alta que nos demais horários, independentemente do tonômetro utilizado. / The determination of intraocular pressure (IOP) is crucial in eye examination. Currently, new tonometers based on different principles are being continuously developed. The objective was to establish reference values of IOP of adults rabbits without the effect of tranquilizers, utilizing the rebound tonometer (Tonovet ) and the applanation tonometer (Tono-Pen Avia) for measurements. It also aimed to advocate the measurement of IOP throughout the day in this species and compare the results obtained with the two tonometers. The IOP was measured throughout the day (6h, 9h, 12h, 15h and 18h) in 38 New Zealand White rabbits (76 eyes), adults, males or females, with mean weight of 3.5kg and an average age of six months. Previously, the Schirmer tear test, fluorescein test, biomicroscopy with slit lamp and direct ophthalmoscopy were performed in all animals. First, the rebound tonometry was performed and after a minimum of 10 minutes anesthetic drops were instilled and applanation tonometry was carried out. IOP obtained using the two techniques was compared by statistical analysis. The average IOP was 9.51 ± 2.62 mmHg (range 3 - 23 mmHg) and 15.44 ± 2.16 mmHg (range 8 – 26mmHg), with Tonovet and Tono-Pen Avia, respectively. Statistic significant difference between the two tonometers was (P <0.001). The linear regression equation that describes the relationship between the two tonometers was: y = 0.4923 x + 10.754 (y= Tonovet e x= Tono-Pen Avia). Earlier in the day, higher IOPs were recorded, but the average behavior of IOP throughout the day with both devices was statistically the same (p = 0.086). The value of the correlation coefficient was r2 = 0.357. The results show that the Tono-Pen Avia is more variable and overestimates the IOP of rabbits when compared with the Tonovet. In the early hours, the IOP of rabbits was higher than at other times, regardless of the tonometer used.
44

Avaliação da pressão intraocular em chinchilas (chinchilla Lanigera) de diferentes faixas etárias utilizando tonometria de rebote

Claros Chacaltana, Flor Diana Yokoay January 2013 (has links)
A aferição da pressão intraocular (PIO) é fundamental durante o exame oftálmico. Objetivou-se estabelecer os valores de referência da PIO de chinchilas de diferentes faixas etárias utilizando o tonômetro de rebote. A PIO foi aferida ao longo do dia às 7, 12 e 19 horas utilizando o tonômetro de rebote (Tonovet®). As chinchilas foram subdivididas em três grupos com 12 animais cada, considerando as idades, designados por GI (animais com idade entre dois a seis meses), GII (com idade entre 20 e 34 meses) e GIII (animais com idade entre 37 e 135 meses). Previamente, foram realizados teste da lágrima de Schirmer, prova da fluoresceína, biomicroscopia com lâmpada de fenda e oftalmoscopia indireta em todos os animais. O valor médio da pressão intraocular encontrado foi 2,49 ± 0,56 mmHg, os valores médios para o grupo I foi de 2,47±0,581 mmHg, no grupo II de 2,47±0,581 mmHg e no grupo III de 2,51±0,531 mmHg. Não foram encontradas diferenças significativas entre a idade e a PIO (P = 0,756). Não foram encontradas diferenças significativas entre as horas do dia e a PIO (P = 0,415). Não foram encontradas diferenças significativas entre os sexos (P = 0,857). Os valores da PIO em chinchilas não sofrem alterações decorrentes do sexo e da idade dos animais. Não ocorre influência do ritmo circadiano na PIO de chinchilas. / The assessment of intraocular pressure (IOP) is essential for the ocular examination. The purpose of this study was to establish reference values of intraocular pressure chinchillas (Chinchilla lanigera) of different age groups. Thirty-six Chinchillas were divided in three groups of 12 animals each, considering the ages designated by GI (animals aged two to six months), GII (aged between 20 and 34 months) and GIII (animals aged between 37 and 135 months). Intraocular pressure was measured at 7, 12 and 19 hours. Tear production was measured, fluorescein test, slit-lamp biomicroscopy and indirect ophthalmoscopy in all animals and IOP was measured using the rebound tonometer (Tono Vet®) set on the P (undefined species) setting, with measurements obtained from each eye. No abnormalities were found on ophthalmic examination. The mean (±SD) of IOP was 2.49 ± 0.56 mmHg, with a range of 2-4 mmHg. The mean (±SD) of IOP for group I, II and III were 2.47 ± 0.581 mmHg, 2.47 ± 0.581 mmHg and 2,51 ± 0.531 mmHg, respectively. No significant differences were found between age and IOP and no significant differences were found between the hours of day and IOP. No significant differences were found between the genders. The IOP in chinchillas is unchanged between genders and age of the animals. The circadian rhythm is not influenced by IOP in chinchillas.
45

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.
46

Optical Performance Test & Analysis of Intraocular Lenses

Choi, Junoh January 2008 (has links)
Cataract is a condition in the eye that if left untreated, could lead to blindness. One of the effective ways to treat cataract is the removal of the cataractous natural crystalline lens and implantation of an artificial lens called an intraocular lens(IOL). The designs of the IOLs have shown improvements over the years to further imitate natural human vision. A need for an objective testing and analysis tool for the latest IOLs grow with the advancements of the IOLs.In this dissertation, I present a system capable of objective test and analysis of the advanced IOLs. The system consists of-Model eye into which an IOL can be inserted to mimic conditions of the human eye.-Modulation Transfer Function measurement setup capable of through-focus test for depth of field studies and polychromatic test for study of effects of chromatization.-Use of Defocus Transfer Function to simulate depth of field characteristic of rotationally symmetric multifocal designs and extension of the function to polychromatic conditions.-Several target imaging experiments for comparison of stray light artifacts and simulation using a non-sequential ray trace package.
47

Análise de qualidade óptica e performance visual em olhos implantados com lentes intraoculares asféricas neutras / Implantation of an aspherical intraocular lens

Santhiago, Marcony Rodrigues de 05 October 2012 (has links)
Objetivo: Determinar se o implante de uma determinada lente intraocular asférica resulta em redução das aberrações oculares e melhora da qualidade ótica e sensibilidade ao contraste sem que ocorra redução critica da profundidade de foco. Desenho: Estudo prospectivo, duplo-cego, randomizado. Métodos: Este estudo que incluiu 25 pacientes com catarata bilateral, uma LIO asférica foi implantada em um olho e uma LIO esférica no olho contralateral. Aberrações de maior ordem e parâmetros de qualidade ótica foram obtidos através de aberrômetro de retinoscopia dinâmica, 1 e 3 meses apos a cirurgia. Foi também medido a acuidade visual com e sem correção e a sensibilidade ao contraste. Acuidade visual para perto e distancia intermediaria foi obtida como forma de medida da profundidade de foco. Resultados: Não houve diferença estatisticamente significativa entre os grupos para acuidade visual corrigida e não corrigida 1 e 3 meses apos a cirurgia. Houve diferença estatisticamente significativa entre os grupos quanto a sensibilidade ao contraste sob condições fotópticas na frequência espacial de 12 ciclos por grau e sob condições mesópicas em todas as frequências espaciais estudadas. O grupo com a LIO Akreos AO obteve menores valores de aberrações de maior ordem totais e de aberração esférica com pupilas de 5 e 6 mm e melhores valores de qualidade ótica comparado ao grupo com LIO Akreos Fit (p <0.05). Não houve diferença significativa entre os grupos quando se investigou visão de perto e intermediaria corrigido para longe. Conclusões: A LIO asférica Akreos AO induziu menos aberrações de maior ordem além de produzir melhores parâmetros de qualidade ótica com melhores resultados de sensibilidade ao contraste em condições mesópicas sem redução critica de profundidade de foco quando comparado a LIO esférica Akreos Fit. / PURPOSE: To determine whether implantation of an aspherical intraocular lens (IOL) results in reduced ocular aberrations and improved optical quality and contrast sensitivity after cataract surgery without critical reduction of depth of focus. DESIGN: Double-blinded, randomized, prospective study. METHODS: In an intraindividual study of 25 patients with bilateral cataract, an aspherical IOL (Akreos Advanced Optic [AO]; Bausch & Lomb, Inc., Rochester, New York, USA) was implanted in one eye and a spherical IOL (Akreos Fit; Bausch & Lomb, Inc) in the fellow eye. Higher-order aberrations with a 5- and 6-mm pupil and optical quality parameters were measured with a dynamic retinoscopy aberrometer at 1 and 3 months after surgery. Uncorrected and best-corrected visual acuity and contrast sensitivity under mesopic and photopic conditions also were measured. Distancecorrected near and intermediate visual acuity were studied as a measurement of depth of focus. RESULTS: There was no statistically significant difference between eyes in uncorrected and best-corrected visual acuity at 1 and 3 months after surgery. There was a statistically significant between-group difference in contrast sensitivity under photopic conditions at 12 cycles per degree and under mesopic conditions at all spatial frequencies. The Akreos AO group obtained statistically significant lower values of higher-order aberrations and spherical aberration with 5- and 6-mm pupils and better optical quality parameters compared with the Akreos Fit group (P < .05). There was no significant difference in distance-corrected near and intermediate visual acuity between both groups. CONCLUSIONS: Aspherical aberration-free Akreos AO IOL induced significantly less higher-order aberrations and spherical aberration than the Akreos Fit. Contrast sensitivity under mesopic conditions and optical quality parameters were better with the Akreos AO with similar results of depth of focus.
48

Comparação da função visual entre pacientes implantados com lentes intraoculares para a correção da presbiopia após a facoemulsificação / Comparison of visual function in patients implanted with intraocular lenses to correct presbyopia after phacoemulsification

Ferreira, Miriam Alves 14 June 2018 (has links)
Objetivo: Estudar maneiras distintas de se corrigir a presbiopia durante a facoemulsificação, através da avaliação do desempenho visual de quatro diferentes modelos de lentes intraoculares; assim como determinar a influência da pupila na recuperação visual e comparar a independência ao uso de óculos após o implante bilateral. Casuística e Métodos: Estudo prospectivo, consecutivo, randomizado que avaliou 60 pacientes (120 olhos) divididos em quatro grupos: lentes multifocais Restor +3, Restor +2.5, monovisão com a lente SN60WF e a pseudoacomodativa Crystalens XO. Foram incluídos pacientes que apresentavam catarata nuclear NI, NII ou cortical similar, que foram submetidos à avaliação oftalmológica completa no pré- operatório e com 1, 3 e 12 meses após a cirurgia. Antes do procedimento, os seguintes exames foram realizados: biometria óptica (Lenstar 900), microscopia especular, avaliação da região macular e das camadas de fibras nervosas por meio de Tomografia de Coerência Óptica (OCT), avaliação da sensibilidade ao contraste (Software Macular Mapping Test) e pupilometria dinâmica (ISCAN INC). As cirurgias foram realizadas por dois cirurgiões, em caráter ambulatorial. Durante o seguimento, nas visitas de 1, 3 e 12 meses após a cirurgia, foram realizadas medidas de acuidade visual longe e perto, mono e binocular, curva de desfoco monocular e pupilometria; e foi aplicado um questionário de satisfação baseado do Visual Functioning Questionnaire - 25 (VFQ 25), assim como medidas de sensibilidade ao contraste. Resultados: Dos 120 olhos selecionados, 114 foram operados, 106 avaliados com um mês de cirurgia, 100 com três meses e 45 pacientes (90 olhos) chegaram a última avaliação com um ano de follow-up. As médias da acuidade visual para longe sem correção binocular foram de 0,09 ± 0,04; 0,09 ± 0,03 e 0,11 ± 0,03 logMar para as lentes Restor +2.5, Restor +3 e SN60WF, respectivamente. Entre elas não se observou diferença significativa. Já para a lente Crystalens XO, a média foi de 0,24 ± 0,04 logMar, constatando-se sua inferioridade para longe de forma significativa estatisticamente em relação às demais. Este resultado foi atribuído à pobre previsibilidade refracional da lente pseudoacomodativa (-1.33 ± 1.37 dpt). Para perto, não houve diferença entre os grupos Restor +3 e monovisão, e as lentes Restor +2.5 e Crystalens apresentaram piores resultados que as duas primeiras, de forma significativa. As médias para perto, em logMar foram de 0,08 ± 0,01; 0,17 ± 0,04; 0,22 ± 0,04 e 0,23 ± 0,07 para as lentes Restor +3, SN60WF, Restor +2.5 e Crystalens, respecivamente. A curva de desfoco das lentes multifocais Restor +3 e Restor +2.5 apresentou dois picos de acuidade visual máxima; o primeiro vértice próximo a zero e o segundo em -2.5 dpt para a Restor +3 e -2 dpt para a Restor +2.5. O segundo vértice da Restor +3 foi mais acentuado em relação ao da Restor +2.5. Já o modelo Crystalens apresentou a curva de desfoco com um pico de acuidade visual máxima, semelhante às lentes monofocais SN60WF, ambas com vértice próximo ao equivalente esférico programado. A partir da curva de desfoco, somando-se as acuidades visuais entre os dois picos de melhor visão, foi criado um índice, denominado Índice de Multifocalidade. O intuito foi criar um indicador de qualidade de visão longe, intermediário e perto para as diversas lentes. O modelo Restor +3 obteve o melhorResumo índice entre as lentes estudadas, porém não mostrou diferença significativa em relação à Restor +2.5, que, por sua vez, não evidenciou diferença quanto à Crystalens. A lente SN60WF teve o pior índice. Já em relação a pupila, não houve interferência de sua amplitude de contração no pré-operatório com as acuidades visuais longe e perto após a cirurgia. Contudo, o tamanho da pupila contraída demonstrou correlação com o índice de multifocalidade. A avaliação da sensibilidade a estímulos de baixo contraste (10%) no campo visual central (8 graus) não foi diferente entre os grupos, tanto no pré quanto no pós-operatório. E em relação à presença de halos e glare, os grupos Restor +3 e +2.5 apresentaram incidência de 26% e 43%, respectivamente; já no grupo SN60WF não houve relato. A satisfação com a performance visual para longe foi de 78% no grupo Crystalens, 80% no grupo monovisão e 90% para as multifocais Restor +3 e Restor +2.5. Para perto, 100 % dos usuários da Restor +3, 80% da monovisão, e 50% dos grupos Restor +2.5 e Crystalens estavam satisfeitos. Finalmente, entre as maneiras distintas de se corrigir a presbiopia na facoemulsificação, o grupo Restor +3 atingiu 93% de independência do uso de óculos após a cirurgia. Inesperadamente e de acordo com os resultados, o modelo Restor +2.5 demonstrou baixa probabilidade de independência (14%). Para a monovisão e Crystalens, 30% e 50%, respectivamente. Conclusões: Tanto a lente multifocal Restor +3 quanto a monovisão com a SN60WF foram eficazes de forma semelhante na correção da presbiopia, porém o modelo Restor +3 proporcionou maior probabilidade de independência ao uso de óculos. Os modelos Restor +2.5 e a Crystalens XO pseudoacomodativa foram inferiores que as duas primeiras, pela lente multifocal Restor +2.5 apresentar resultados aquém do previsto para perto, com baixa independência do uso de óculos; e a Crystalens mostrar imprevisibilidade refracional biométrica, comprometendo a visão de longe dos usuários. A respeito da dinâmica pupilar, as medidas do pré e pós-operatório não evidenciaram interferência no desempenho visual das lentes multifocais, monovisão e pseudoacomodativa; exceto no índice de multifocalidade, onde as pupilas contraídas apresentaram correlação com os resultados. / Objective: Study different ways of correcting presbyopia in phacoemulsification by comparing visual performance of four different models of intraocular lenses; as well as to determine the influence of the pupil on visual recovery and to compare the independence of glasses after bilateral implant. Casuistic and Methods: Prospective, consecutive, randomized study with 60 patients (120 eyes) divided into 4 groups: Restor +3 and Restor +2.5 multifocal lenses, monovision with SN60WF and Crystalens XO pseudoacommodative lens. Patients who had nuclear NI, NII or similar cortical cataract were submitted to a complete ophthalmologic evaluation in the preoperative period and at 1,3 and 12 months after surgery. Before procedure, the following tests were performed: optical biometry (Lenstar 900), specular microscopy, analyse of macular region and nerve fiber layers with Optical Coherence Tomography (OCT), contrast sensitivity (MMTest Software) and pupilometry dynamics (ISCAN INC). Surgeries were performed by two surgeons. During the follow-up, visits of 1, 3 and 12 months were measured far and near, mono and binocular visual acuity, defocous curve, pupilometry, satisfaction questionnaire was applied based on Visual Functioning Questionnaire - 25 (VFQ 25) as well as a contrast sensitivity measurements (Macular Mapping Test). Results: Of the 120 eyes selected, 114 were operated, 106 were evaluated at 1 month of surgery, 100 at 3 months, and 45 pacients (90 eyes) achieve the last evaluation at 1 year follow-up. The mean visual acuity for far without binocular correction was 0.09 ± 0.04; 0.09 ± 0.03 and 0.11 ± 0.03 logMar for the lenses Restor +2.5, Restor +3 and SN60WF respectively. Between them there was no difference. For the Crystalens XO lens, the mean was 0.24 ± 0.04 logMar, showing its inferiority statistically significantly different than the others. This result was attributed by the poor refractive predictability of the pseudoacommodative lens (-1.33 ± 1.37 dpt). For close, there was no difference between the Restor +3 and monovision groups, and the Restor +2.5 and Crystalens lenses were worse than the first with statistical significance . The means for near were 0,08 ± 0,01; 0.17 ± 0.04; 0.22 ± 0.04 and 0.23 ± 0.07 for the Restor +3, SN60WF-, Restor +2.5 and Crystalens lenses. The defocous curve of the multifocal lenses Restor +3 and Restor +2.5 had 2 peaks of maximum visual acuity, the first in zero and the second close to -2.5 dpt for Restor +3 and -2 dpt for Restor +2.5. The second vertex of Restor +3 was more pronounced than Restor +2.5. The Crystalens group presented a defocous curve with only 1 peak of maximum visual acuity, as well as the SN60WF monofocal lenses, both with a vertex near the programmed spherical equivalent. From the defocous curve, adding the visual acuity between the two best view peaks, an index was created, called Multifocality Index. The aim was to create a far, intermediate and close quality index for the various lenses. Restor +3 obtained the best index, but that was no significantly different than Restor +2.5, which had no difference with Crystalens. SN60WF achieved the worst index. Regarding the pupil, did no notice interference of its preoperative contraction amplitude with the visual acuities far and near after the surgery. However, the size of contracted pupil had a statistically significant correlation with the multifocality index. The sensitivity to low contrastAbstract stimuli (10%) in the central visual field (8 degrees) was no different between the groups, both in the pre and postoperative periods. About presence of halos and glare, the multifocal lenses Restor +3 and Restor +2.5 showed 26% and 43% respectively. No cases were reportaded with model SN60WF. The satisfaction with the far visual performance was 78% in the Crystalens group, 80% for monovision and 90% in the multifocal lenses Restor +3 and +2.5. For near, 100% of Restor +3 users, 80% of monovision, and 50% of Restor +2.5 and Crystalens groups were satisfied. Finally, among the distinct ways of correcting presbyopia in phacoemulsification, the Restor +3 group showed that 93% of their users achieved independence of the glasses after surgery. Unexpectedly and according to the visual results, the Restor +2.5 model showed a low probability of independence, 14%. For monovision and Crystalens, 30% and 50% respectively. Conclusions: Both Restor +3 and monovision with SN60WF were similarly effective for correction of presbyopia, but the Restor +3 model provides a greater probability of independence from wearing glasses. The Restor +2.5 and pseudoacommodative models Crystalens XO were worst than the first two, because the multifocal Restor +2.5 presented results below the predicted for near, with low independence of the use of glasses; and model Crystalens unexpected biometric refractive unpredictability, compromising the view from far away from users. Regarding the pupillary dynamics, the pre and postoperative measurements showed no interference in the visual performance of multifocal, monovision and pseudoacommodative lenses; except in the multifocality index, where pupils contracted had a correlation with the results.
49

Resonator sensor technique for medical use : An intraocular pressure measurement system

Eklund, Anders January 2002 (has links)
<p> In the work of this doctoral dissertation a new resonator sensor technique, first presented in 1989, has been further developed and evaluated with focus on technical characteristics and applications within the medical field.</p><p> In a first part a catheter-type tactile sensor using the resonator sensor technique was evaluated in a silicone model and applied to human prostate in vitro. The main finding was that different histological compositions of prostate tissue correlated with the frequency shift, .fS, of the resonator sensor and that the common property was the hardness of the tissue. The results indicated that hardness of the prostate tissue, and maybe hardness of human tissue in general, can be expressed according to a cone penetration standard (DIN ISO 2137) and that the hardness can be measured with this tactile sensor system. The tissue hardness application for the resonator sensor technique has to be further developed and evaluated in a larger study. The study also produced results that has led to the basic understanding of the resonator sensor system. One important result was that .fS of the sensor system was related to the contact area between sensor and sample. This indicated that the resonance sensor could be used for contact area measurement.</p><p> In a second part, containing three studies, the area-sensing capability from the first study was utilised in the development and evaluation of the applanation resonator sensor (ARS) for measurement of intraocular pressure (IOP). For the purpose of evaluating IOP-tonometers, an in vitro pig-eye model was developed, and it was shown that a saline column connected to the vitreous chamber could be used successfully to induce variations in IOP.</p><p> A ARS sensor with a flat contact surface was applied onto the cornea with constant force and .fS was measured. A mathematical model based on the Imbert-Fick law and the assumption that .fS was linearly related to contact area was proposed and verified with a convincing result. IOP measured with the ARS correlated well (r=0.92, n=360) with the IOP elicited by a saline column.</p><p> The ARS in a constant-force arrangement was evaluated on healthy human subjects in vivo. The results verified the sensor principle but revealed a nonnegligible source of error in off-centre positioning between the sensor and cornea. The sensor probe was redesigned and evaluated in the in vitro model. The new probe, with a spherical contact surface against the eye reduced the sensitivity to off-centre positioning. It was also shown that a .fS normalisation procedure could reduce the between-eye differences.</p><p> The ARS method for IOP measurement was further developed using combined continuous force and area measurement during the dynamic phase when the sensor initially contacts the cornea. A force sensor was included with the resonator sensor in one probe. Evaluation was performed with the in vitro pig-eye model. The hypothesis was that the IOP could be deduced from the differential change of force and area during that phase. The study showed good accuracy and good reproducibility with a correlation of r=0.994 (n=414) between measured pressure in the vitreous chamber and IOP according to the ARS. Measurement time was short, 77 ms after initial contact. Problems with inter-eye differences and low resolution at high pressures were reduced. The ARS method is the first to combine simultaneous, continuous sampling of both parameters included in the applanation principle. Consequently, there is a potential for reducing errors in the clinical IOP tonometry. </p>
50

Resonator sensor technique for medical use : an intraocular pressure measurement system

Eklund, Anders January 2002 (has links)
In the work of this doctoral dissertation a new resonator sensor technique, first presented in 1989, has been further developed and evaluated with focus on technical characteristics and applications within the medical field. In a first part a catheter-type tactile sensor using the resonator sensor technique was evaluated in a silicone model and applied to human prostate in vitro. The main finding was that different histological compositions of prostate tissue correlated with the frequency shift, .fS, of the resonator sensor and that the common property was the hardness of the tissue. The results indicated that hardness of the prostate tissue, and maybe hardness of human tissue in general, can be expressed according to a cone penetration standard (DIN ISO 2137) and that the hardness can be measured with this tactile sensor system. The tissue hardness application for the resonator sensor technique has to be further developed and evaluated in a larger study. The study also produced results that has led to the basic understanding of the resonator sensor system. One important result was that .fS of the sensor system was related to the contact area between sensor and sample. This indicated that the resonance sensor could be used for contact area measurement. In a second part, containing three studies, the area-sensing capability from the first study was utilised in the development and evaluation of the applanation resonator sensor (ARS) for measurement of intraocular pressure (IOP). For the purpose of evaluating IOP-tonometers, an in vitro pig-eye model was developed, and it was shown that a saline column connected to the vitreous chamber could be used successfully to induce variations in IOP. A ARS sensor with a flat contact surface was applied onto the cornea with constant force and .fS was measured. A mathematical model based on the Imbert-Fick law and the assumption that .fS was linearly related to contact area was proposed and verified with a convincing result. IOP measured with the ARS correlated well (r=0.92, n=360) with the IOP elicited by a saline column. The ARS in a constant-force arrangement was evaluated on healthy human subjects in vivo. The results verified the sensor principle but revealed a nonnegligible source of error in off-centre positioning between the sensor and cornea. The sensor probe was redesigned and evaluated in the in vitro model. The new probe, with a spherical contact surface against the eye reduced the sensitivity to off-centre positioning. It was also shown that a .fS normalisation procedure could reduce the between-eye differences. The ARS method for IOP measurement was further developed using combined continuous force and area measurement during the dynamic phase when the sensor initially contacts the cornea. A force sensor was included with the resonator sensor in one probe. Evaluation was performed with the in vitro pig-eye model. The hypothesis was that the IOP could be deduced from the differential change of force and area during that phase. The study showed good accuracy and good reproducibility with a correlation of r=0.994 (n=414) between measured pressure in the vitreous chamber and IOP according to the ARS. Measurement time was short, 77 ms after initial contact. Problems with inter-eye differences and low resolution at high pressures were reduced. The ARS method is the first to combine simultaneous, continuous sampling of both parameters included in the applanation principle. Consequently, there is a potential for reducing errors in the clinical IOP tonometry.

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