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Resonator sensor technique for medical use : An intraocular pressure measurement systemEklund, 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>
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Resonator sensor technique for medical use : an intraocular pressure measurement systemEklund, 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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Applanation Resonance Tonometry for Intraocular Pressure MeasurementHallberg, Per January 2006 (has links)
Elevated intraocular pressure (IOP) is one of the major risk factors for glaucoma. Since glaucoma is a leading cause of blindness, reliable methods for measuring the IOP are important. This doctoral dissertation presents a new method, applanation resonance tonometry (ART), for measurement of IOP. The method is based on resonance sensor technology combined with the novel multipoint analysis of continuously sampled data of both contact force and contact area. The ART was evaluated in in vitro porcine-eye studies as well as in clinic on both healthy volunteers and patients. A new symmetric probe with a larger sensor tip and improved aligning light was developed and evaluated in vitro. It showed that the error from off-centring was highly reduced. The new ART probe, used as a biomicroscope device (ARTBiom) and as a handheld device (ARTHand), was further evaluated in a clinical study designed in accordance with the International Standard Organisation’s (ISO) requirement. Both the ARTBiom and the ARTHand met the precision set by the requirements. Laser surgery is a common way to correct vision. The biomechanical effect of photorefractive keratectomy (PRK) on IOP measurements was evaluated using Goldmann applanation tonometry (GAT) and ART in an in vitro study. Both methods were affected, but to a different extent. The flat contact probe of GAT, as compared with the convex tip of ART, and single point vs. multipoint approach, provide explanation to the ART advantage regarding measurement error of IOP after PRK. In conclusion, resonance sensor technology has made it possible to introduce a new multipoint method for measuring IOP, and the method is relevant for measuring IOP in humans. It may be possible to reduce errors in the clinical measurement of IOP with this new method, especially after corneal surgery. The ART has the potential to become a useful clinical instrument for IOP measurement.
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Pressão intraocular média obtida por três diferentes avaliadores utilizando os tonômetros de rebote e de aplanação em equinosMoreno, Tatiana Martinez January 2016 (has links)
A mensuração da pressão intraocular (PIO) é essencial para o exame oftálmico, pois permite o diagnóstico de doenças oftálmicas como uveíte e glaucoma, além de auxiliar no monitoramento das cirurgias intraoculares. Objetivou-se comparar a tonometria de rebote com a tonometria de aplanação em equinos. Além disso, determinar a reprodutibilidade dos valores obtidos em ambos os aparelhos. A PIO foi aferida em 30 equinos da raça Crioula, machos ou fêmeas, com idade entre um e 16 anos utilizando o tonômetro de rebote (TonoVet®) e o tonômetro de aplanação (Tonopen Avia®). Previamente a aferição da PIO, todos os animais foram submetidos ao exame oftálmico incluindo, avaliação dos reflexos pupilares, teste da lágrima de Schirmer, prova da fluoresceína e biomicroscopia com lâmpada de fenda portátil. Foram utilizados apenas bulbos oculares hígidos. A análise estatística foi feita com ANOVA e teste t de Student. A reprodutibilidade foi avaliada pelo cálculo do coeficiente de correlação intraclasse (ICC). A média da PIO foi de 26,16 ± 5,13 mmHg utilizando o tonômetro de rebote e de 22,55 ±7,32 mmHg com o tonômetro de aplanação. A média da PIO de acordo com o avaliador utilizando o tonômetro de rebote foi de 25,27 ± 4,9 mmHg para o examinador A, 25,80 ± 5,2 mmHg para o examinador B e de 27,40 ± 5,1 mmHg para o examinador C. Com o tonômetro de aplanação as médias obtidas foram de 20,03 ± 4,5 mmHg com o examinador A, 19,67 ± 6,0 mmHg com o examinador B e de 27,97 ± 10,3 mmHg com o examinador C (p<2,3). O ICC foi de 0,18 para o tonômetro de aplanação e de 0,41 para o tonômeto de rebote. Os valores da pressão intraocular média obtidos com o tonômetro de rebote são superestimados quando comparados aos valores obtidos com o tonômetro de Tonopen Avia® em equinos saudáveis. Comparativamente ao Tonopen Avia® os valores obtidos com o Tonovet® demonstraram maior reprodutibilidade. / The measurement of intraocular pressure (IOP) is essential for the ophthalmic examination, as it allows the diagnosis of eye diseases such as uveitis and glaucoma, as well as aid in the monitoring of intraocular surgery. This study aimed to compare the mean intraocular pressure (IOP) values in horses obtained by three different examiners using the rebound and applanation tonometer’s. Each examiner measured the IOP of 30 “Crioulo” horses, males or females, aged one to 16 years old, using rebound tonometer and applanation tonometer. Previous to the experiment an ophthalmic examination was performed in horses. Only animals without alterations were selected. Three veterinarians measured IOP with rebound (Tonovet®) and applanation tonometer’s (TonoPen Avia®). Comparisons were made using ANOVA and student t test. Intraclass correlation coefficient (ICC) was calculated for reproducibility. IOP measurements resulted in mean values of 26.16 ± 5.13 mmHg for rebound tonometer and 22.55 ±7.32 mmHg for applanation tonometer. These values were different on statistical analysis. Rebound tonometer mean values, according with the examiner, were: A 25.27 ± 4.9 mmHg, B 25.80 ± 5.2, C 27.40 ± 5.1 mmHg. For applanation tonometer the mean IOP for examiner A (20.03 ± 4.5 mmHg), B (19.67 ± 6.0 mmHg), C (27.97 ± 10.3 mmHg). With the Tonopen Avia® tonometer examiner C measured higher IOP’s than examiners A and B. Intraclass correlation coefficient was 0.41 for rebound tonometer was 0.18 for applanation tonometer. It was observed that the values obtained with the Tonovet® were overestimated compared to Tonopen Avia® in healthy horses. When compared with Tonopen Avia® values obtained with the Tonovet® showed a higher reproducibility.
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Pressão intraocular média obtida por três diferentes avaliadores utilizando os tonômetros de rebote e de aplanação em equinosMoreno, Tatiana Martinez January 2016 (has links)
A mensuração da pressão intraocular (PIO) é essencial para o exame oftálmico, pois permite o diagnóstico de doenças oftálmicas como uveíte e glaucoma, além de auxiliar no monitoramento das cirurgias intraoculares. Objetivou-se comparar a tonometria de rebote com a tonometria de aplanação em equinos. Além disso, determinar a reprodutibilidade dos valores obtidos em ambos os aparelhos. A PIO foi aferida em 30 equinos da raça Crioula, machos ou fêmeas, com idade entre um e 16 anos utilizando o tonômetro de rebote (TonoVet®) e o tonômetro de aplanação (Tonopen Avia®). Previamente a aferição da PIO, todos os animais foram submetidos ao exame oftálmico incluindo, avaliação dos reflexos pupilares, teste da lágrima de Schirmer, prova da fluoresceína e biomicroscopia com lâmpada de fenda portátil. Foram utilizados apenas bulbos oculares hígidos. A análise estatística foi feita com ANOVA e teste t de Student. A reprodutibilidade foi avaliada pelo cálculo do coeficiente de correlação intraclasse (ICC). A média da PIO foi de 26,16 ± 5,13 mmHg utilizando o tonômetro de rebote e de 22,55 ±7,32 mmHg com o tonômetro de aplanação. A média da PIO de acordo com o avaliador utilizando o tonômetro de rebote foi de 25,27 ± 4,9 mmHg para o examinador A, 25,80 ± 5,2 mmHg para o examinador B e de 27,40 ± 5,1 mmHg para o examinador C. Com o tonômetro de aplanação as médias obtidas foram de 20,03 ± 4,5 mmHg com o examinador A, 19,67 ± 6,0 mmHg com o examinador B e de 27,97 ± 10,3 mmHg com o examinador C (p<2,3). O ICC foi de 0,18 para o tonômetro de aplanação e de 0,41 para o tonômeto de rebote. Os valores da pressão intraocular média obtidos com o tonômetro de rebote são superestimados quando comparados aos valores obtidos com o tonômetro de Tonopen Avia® em equinos saudáveis. Comparativamente ao Tonopen Avia® os valores obtidos com o Tonovet® demonstraram maior reprodutibilidade. / The measurement of intraocular pressure (IOP) is essential for the ophthalmic examination, as it allows the diagnosis of eye diseases such as uveitis and glaucoma, as well as aid in the monitoring of intraocular surgery. This study aimed to compare the mean intraocular pressure (IOP) values in horses obtained by three different examiners using the rebound and applanation tonometer’s. Each examiner measured the IOP of 30 “Crioulo” horses, males or females, aged one to 16 years old, using rebound tonometer and applanation tonometer. Previous to the experiment an ophthalmic examination was performed in horses. Only animals without alterations were selected. Three veterinarians measured IOP with rebound (Tonovet®) and applanation tonometer’s (TonoPen Avia®). Comparisons were made using ANOVA and student t test. Intraclass correlation coefficient (ICC) was calculated for reproducibility. IOP measurements resulted in mean values of 26.16 ± 5.13 mmHg for rebound tonometer and 22.55 ±7.32 mmHg for applanation tonometer. These values were different on statistical analysis. Rebound tonometer mean values, according with the examiner, were: A 25.27 ± 4.9 mmHg, B 25.80 ± 5.2, C 27.40 ± 5.1 mmHg. For applanation tonometer the mean IOP for examiner A (20.03 ± 4.5 mmHg), B (19.67 ± 6.0 mmHg), C (27.97 ± 10.3 mmHg). With the Tonopen Avia® tonometer examiner C measured higher IOP’s than examiners A and B. Intraclass correlation coefficient was 0.41 for rebound tonometer was 0.18 for applanation tonometer. It was observed that the values obtained with the Tonovet® were overestimated compared to Tonopen Avia® in healthy horses. When compared with Tonopen Avia® values obtained with the Tonovet® showed a higher reproducibility.
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Pressão intraocular média obtida por três diferentes avaliadores utilizando os tonômetros de rebote e de aplanação em equinosMoreno, Tatiana Martinez January 2016 (has links)
A mensuração da pressão intraocular (PIO) é essencial para o exame oftálmico, pois permite o diagnóstico de doenças oftálmicas como uveíte e glaucoma, além de auxiliar no monitoramento das cirurgias intraoculares. Objetivou-se comparar a tonometria de rebote com a tonometria de aplanação em equinos. Além disso, determinar a reprodutibilidade dos valores obtidos em ambos os aparelhos. A PIO foi aferida em 30 equinos da raça Crioula, machos ou fêmeas, com idade entre um e 16 anos utilizando o tonômetro de rebote (TonoVet®) e o tonômetro de aplanação (Tonopen Avia®). Previamente a aferição da PIO, todos os animais foram submetidos ao exame oftálmico incluindo, avaliação dos reflexos pupilares, teste da lágrima de Schirmer, prova da fluoresceína e biomicroscopia com lâmpada de fenda portátil. Foram utilizados apenas bulbos oculares hígidos. A análise estatística foi feita com ANOVA e teste t de Student. A reprodutibilidade foi avaliada pelo cálculo do coeficiente de correlação intraclasse (ICC). A média da PIO foi de 26,16 ± 5,13 mmHg utilizando o tonômetro de rebote e de 22,55 ±7,32 mmHg com o tonômetro de aplanação. A média da PIO de acordo com o avaliador utilizando o tonômetro de rebote foi de 25,27 ± 4,9 mmHg para o examinador A, 25,80 ± 5,2 mmHg para o examinador B e de 27,40 ± 5,1 mmHg para o examinador C. Com o tonômetro de aplanação as médias obtidas foram de 20,03 ± 4,5 mmHg com o examinador A, 19,67 ± 6,0 mmHg com o examinador B e de 27,97 ± 10,3 mmHg com o examinador C (p<2,3). O ICC foi de 0,18 para o tonômetro de aplanação e de 0,41 para o tonômeto de rebote. Os valores da pressão intraocular média obtidos com o tonômetro de rebote são superestimados quando comparados aos valores obtidos com o tonômetro de Tonopen Avia® em equinos saudáveis. Comparativamente ao Tonopen Avia® os valores obtidos com o Tonovet® demonstraram maior reprodutibilidade. / The measurement of intraocular pressure (IOP) is essential for the ophthalmic examination, as it allows the diagnosis of eye diseases such as uveitis and glaucoma, as well as aid in the monitoring of intraocular surgery. This study aimed to compare the mean intraocular pressure (IOP) values in horses obtained by three different examiners using the rebound and applanation tonometer’s. Each examiner measured the IOP of 30 “Crioulo” horses, males or females, aged one to 16 years old, using rebound tonometer and applanation tonometer. Previous to the experiment an ophthalmic examination was performed in horses. Only animals without alterations were selected. Three veterinarians measured IOP with rebound (Tonovet®) and applanation tonometer’s (TonoPen Avia®). Comparisons were made using ANOVA and student t test. Intraclass correlation coefficient (ICC) was calculated for reproducibility. IOP measurements resulted in mean values of 26.16 ± 5.13 mmHg for rebound tonometer and 22.55 ±7.32 mmHg for applanation tonometer. These values were different on statistical analysis. Rebound tonometer mean values, according with the examiner, were: A 25.27 ± 4.9 mmHg, B 25.80 ± 5.2, C 27.40 ± 5.1 mmHg. For applanation tonometer the mean IOP for examiner A (20.03 ± 4.5 mmHg), B (19.67 ± 6.0 mmHg), C (27.97 ± 10.3 mmHg). With the Tonopen Avia® tonometer examiner C measured higher IOP’s than examiners A and B. Intraclass correlation coefficient was 0.41 for rebound tonometer was 0.18 for applanation tonometer. It was observed that the values obtained with the Tonovet® were overestimated compared to Tonopen Avia® in healthy horses. When compared with Tonopen Avia® values obtained with the Tonovet® showed a higher reproducibility.
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Goldmann tonometry tear film error and partial correction with a shaped applanation surfaceMcCafferty, Sean, Enikov, Eniko, Schwiegerling, Jim, Ashley, Sean 01 1900 (has links)
Purpose: The aim of the study was to quantify the isolated tear film adhesion error in a Goldmann applanation tonometer (GAT) prism and in a correcting applanation tonometry surface (CATS) prism. Methods: The separation force of a tonometer prism adhered by a tear film to a simulated cornea was measured to quantify an isolated tear film adhesion force. Acrylic hemispheres (7.8 mm radius) used as corneas were lathed over the apical 3.06 mm diameter to simulate full applanation contact with the prism surface for both GAT and CATS prisms. Tear film separation measurements were completed with both an artificial tear and fluorescein solutions as a fluid bridge. The applanation mire thicknesses were measured and correlated with the tear film separation measurements. Human cadaver eyes were used to validate simulated cornea tear film separation measurement differences between the GAT and CATS prisms. Results: The CATS prism tear film adhesion error (2.74 +/- 0.21 mmHg) was significantly less than the GAT prism (4.57 +/- 0.18 mmHg, p<0.001). Tear film adhesion error was independent of applanation mire thickness (R-2=0.09, p=0.04). Fluorescein produces more tear film error than artificial tears (+0.51 +/- 0.04 mmHg; p<0.001). Cadaver eye validation indicated the CATS prism's tear film adhesion error (1.40 +/- 0.51 mmHg) was significantly less than that of the GAT prism (3.30 +/- 0.38 mmHg; p=0.002). Conclusion: Measured GAT tear film adhesion error is more than previously predicted. A CATS prism significantly reduced tear film adhesion error by similar to 41%. Fluorescein solution increases the tear film adhesion compared to artificial tears, while mire thickness has a negligible effect.
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Effect of numerical modelling assumptions on the simulated corneal response during Goldmann applanation tonometryBotha, Natasha January 2014 (has links)
It is widely known that Central Corneal Thickness (CCT) and Radius of Curvature (RoC)
in
uence the estimated IntraOcular Pressure (IOP) obtained from Goldmann Applanation
Tonometry (GAT). However, not much is known about the in
uence of corneal material
properties, especially in a clinical setting.
Several numerical studies have been conducted in an attempt to quantify the in
uence of
corneal material properties on the IOP. These studies agree that corneal material properties
do in
uence the estimated IOP, which contradict the initial premise on which GAT was
designed, namely that material properties do not in
uence the obtained GAT readings. Also,
there is no consensus among these studies with respect to corneal material properties, thus a
wide range of proposed properties exist.
A possible explanation for this range of available corneal properties is the numerical modi elling assumptions used, which seem to be quite different. Different sets of experimental in ation test data were used to calibrate the constitutive models and different limbal boundary conditions were applied to simulate the experimental setup as well as in vivo conditions during GAT simulations. Therefore the purpose of this study is to determine whether these modelling assumptions in uence the obtained IOP and ultimately the overall conclusions.
A Finite Element (FE) model of the human cornea is developed, implementing a constitutive model to represent the complex corneal structure and two limbal boundary conditions. This model is then calibrated using two different sets of experimental in
ation test data. During calibration of the fibre reinforced elastic constitutive model it is found that independent of the assumptions made regarding the material coe cients, that the numerical in ation data compare well with the experimental data for all cases.
Using this model a GAT simulation is conducted to estimate the IOP and the in
uence of the modelling assumptions, cornea geometry and material properties are then investigated. The results indicate that the modelling assumptions, cornea geometry and material properties do infuence the estimated IOP. However, when assuming the cornea ground substance stiffness to be constant, it is found that the in
uence on IOP due to material properties is not as
significant. A correction equation is also proposed to account for the corneal geometric
properties by calibrating the numerical model for a numerically normal cornea. This is done by utilising the various data sets which are obtained during the calibration of the constitutive model with the experimental inflation test data.
It is concluded that using only inflation data to calibrate the constitutive model is not sufficient to uniquely describe the corneal material. This is evident as different material data sets are obtained, even though the experimental inflation
data is matched well for a variety of
considered cases. Each of these material data sets, in conjunction with geometric properties,
yield different estimates for IOP during GAT simulations.
This study therefore recommends the use of additional experimental data, such as strip
extensometry, along with inflation test data to adequately calibrate a numerical model. It
should also be noted that when modelling GAT care should be taken when considering the choice of limbal boundary condition, experimental data for calibration and assumptions made with regards to material coe cients, as these choices could potentially influence the outcomes and conclusions of a study. / Dissertation (MEng)--University of Pretoria, 2014. / gm2014 / Mechanical and Aeronautical Engineering / unrestricted
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Reabilitação cardiovascular de curto prazo em mulheres com diabetes mellitus tipo 2 : repercussões sobre o balanço redox, a função vascular e a qualidade de vida / Effects of short-term cardiovascular rehabilitation in women with type 2 diabetes mellitus : repercussions on redox balance, vascular function and quality of lifeSilva, Weriton Ferreira da 04 August 2009 (has links)
Introduction: Diabetes is characterized by insufficient production of insulin and/or incapacity of this hormone in playing its functions. Such disease impairs the function of the endothelium, the latter capable of regulating the vascular tone and important in the control of inflammatory response as well. Once dysfunctional, the endothelium no longer exhibits such functions, occurring mostly redox imbalance, this one evident in diabetic patients. Nowadays, several studies point to endothelial dysfunction as a contributor in the development of diabetic vascular complications, while the practice of physical activity, although of low intensity, brings benefits in the handling of type 2 diabetes, including reduction of cardiovascular risk factors. Physical intervention as a therapeutic proposal appears to be a promising way in the clinical management of diabetes mellitus, probably avoiding the progression of systemic complications. Aim: To assess the vascular function and the REDOX balance in patients with type 2 diabetes mellitus (T2DM) before and after the cardiovascular rehabilitation for six weeks. Methods: 43 diabetic female patients aged 57.50 ± 2.02 years were selected from the ambulatory of Endocrinology at Prof. Alberto Antunes Teaching Hospital (Federal University of Alagoas). The diagnosis for T2DM was established according to the criteria of the Brazilian Society of Diabetes (2007). Initial assessment was performed by laboratory and clinical evaluation. The cardiovascular rehabilitation program consisted of six weeks of aerobic training (50 to 70% of the maximum heart rate), associated to endurance training. Four patients have completed the six weeks rehabilitation program. Assessment of biochemical profile (fasting and postprandial glucose, glicosilated hemoglobin, total cholesterol, VLDL, LDL, HDL, triglycerides, uric acid, albumin and creatinin), REDOX balance (SOD and catalase activity and lipid peroxidation) and quality of life (through the application of the SF-36) were performed before and after the rehabilitation program period. Indirect assessment of vascular function was performed by the Augmentation Index (AI), wave reflection, systolic and diastolic blood pressure and pulse pressure, which were obtained by the left radial artery tonometry (HEM-9000 AI device). Physical capacity was assessed by the six-minute walk test. Results: After rehabilitation, there was a significant reduction in the serum albumin levels (3.52 ± 0.478 vs 3.85 ± 0.50 mg/dL, P=0.0159) and an increase in the serum acid uric levels (5.00 ± 0.25 vs 4.57 ± 0.21 mg/dL, P=0.0298), without, however, alterations in the creatinin levels (P=0.3760). It was observed a reduction in the systolic and diastolic blood pressure (141.50 ± 3.67 vs 117.00 ± 6.01 mmHg, p<0.01; 77.75 ± 1.48 vs 71.25 ± 3.03 mmHg, P<0.05, respectively) and in the pulse pressure (63.75 ± 2.29 vs 45.750 ± 3.68 mmHg, P<0.01), without improvement in the Augmentation Index, with an improvement in five parameters during the assessment of the quality of life: physical functioning (25.00 ± 17.56 vs 93.75 ± 6.25 %, P<0.05), vitality (31.250 ± 10.48 vs 87.50 ± 5.20 %, P<0.05), social functioning (50.00 ± 17.68 vs 100.00 ± 0.00 %, P<0.05), role physical (47.50 ± 8.53 vs 92.50 ± 3.22 %, P<0.01) and bodily pain (21.62 ± 10.68 vs 65.75± 12.49 %, P<0.01). There were no statistically significant changes neither in the glycemic and lipid profiles nor in the functional capacity. Conclusion: The cardiovascular rehabilitation program during six weeks in diabetic patients was capable of promoting improvement in hemodynamic parametres and in the quality of life, without greater changes in the biochemical profile and functional capacity. These observations permit to consider that in diabetic patients the cardiovascular rehabilitation should be initiated as soon as possible to promote a reduction in the cardiovascular risk in these individuals. / Introdução: O diabetes caracteriza-se pela produção insuficiente de insulina e/ou pela incapacidade desse hormônio em desempenhar suas funções. Tal doença prejudica a função do endotélio, tecido este capaz de regular o tônus vascular e a resposta inflamatória. Quando disfuncional, esta camada celular não mais exibe tais funções, ocorrendo, principalmente, o desbalanço redox, evidente em pacientes diabéticos. Atualmente, diversos estudos apontam para a disfunção endotelial como contribuinte para o desenvolvimento das complicações vasculares diabéticas, ao passo que a prática de atividade física, ainda que de baixa intensidade, traz benefícios no manejo do diabetes mellitus tipo 2, incluindo redução dos fatores de risco cardiovascular. Desta forma, a intervenção física como proposta terapêutica apresenta-se promissora no manejo clinico do diabetes mellitus, podendo evitar a progressão de complicações sistêmicas. Objetivo: Avaliar a função vascular e o balanço redox em pacientes portadores de diabetes mellitus tipo 2 (DMII), antes e após a reabilitação cardiovascular por seis semanas. Método: 43 pacientes do sexo feminino com idade média de 57,50 ± 2,02 foram selecionadas do ambulatório de Endocrinologia do Hospital Universitário Prof. Alberto Antunes (Universidade Federal de Alagoas). O diagnóstico de DMII foi estabelecido de acordo com os critérios da Sociedade Brasileira de Diabetes (2007). A avaliação inicial foi feita através de exames clínicos e laboratoriais. O programa de reabilitação cardiovascular consistiu de seis semanas de exercício aeróbio (50 a 70% da freqüência cardíaca máxima) associado a exercícios resistidos. Quatro pacientes completaram as seis semanas de reabilitação. Avaliação do perfil bioquímico (glicemia de jejum e pós-prandial, hemoglobina glicosilada, colesterol total, VLDL, LDL, HDL, triglicerídeos, ácido úrico, albumina e creatinina), balanço REDOX (atividades da SOD e catalase e peroxidação lipídica) e qualidade de vida (através da aplicação do SF-36) foram realizadas antes e após o programa de reabilitação. A avaliação indireta da função vascular foi realizada através do Augmentation Index (AI), onda de reflexão, pressões arteriais sistólica e diastólica e pressão de pulso, obtidos por tonometria da artéria radial esquerda (com o equipamento HEM-9000 AI). A capacidade física foi avaliada através do teste de caminhada de seis minutos. Resultados: Após a reabilitação, houve redução significativa dos níveis séricos albumina (3,52 ± 0,478 vs 3,85 ± 0,50 mg/dL, P=0,0159) e aumento dos níveis de ácido úrico (5,00 ± 0,25 vs 4,57 ± 0,21 mg/dL, P=0,0298), sem, entretanto, alterações dos níveis de creatinina (p=0,3760). Também foram reduzidas as pressões arteriais sistêmicas sistólica e diastólica (141,50 ± 3,67 vs 117,00 ± 6,01 mmHg, P<0,01; 77,75 ± 1,48 vs 71,25 ± 3,03 mmHg, P<0,05, respectivamente) e a pressão de pulso (63,75 ± 2,29 vs 45,750 ± 3,68 mmHg, P<0,01), sem redução no Augmentation Index, com melhora em cinco parâmetros da qualidade de vida: aspectos físicos (25,00 ± 17,56 vs 93,75 ± 6,25 %, P<0,05), vitalidade (31,250 ± 10,48 vs 87,50 ± 5,20 %, P<0,05), aspectos sociais (50,00 ± 17,68 vs 100,00 ± 0,00 %, P<0,05), capacidade funcional (47,50 ± 8,53 vs 92,50 ± 3,22 %, P<0,01) e dor (21,62 ± 10,68 vs 65,75 ± 12,49 %, P<0,01). Não foram observadas variações estatisticamente significativas para o perfil glicêmico, lipídico e capacidade funcional. Conclusão: O programa de reabilitação cardiovascular por seis semanas em pacientes diabéticas foi capaz de promover melhora em parâmetros hemodinâmicos e na qualidade de vida, sem maiores mudanças no perfil bioquímico e capacidade funcional. Estas observações permitem considerar que em pacientes diabéticos a reabilitação cardiovascular deve ser iniciada o mais precoce possível a fim de promover redução do risco cardiovascular nestes indivíduos.
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Uso do tonômetro de aplanação portátil Kowa HA-2 na mensuração da pressão intraocular em gatos / Use of portable applanation tonometer Kowa HA-2 in the measurement of intraocular pressure in catsRicci, Cláudia Lizandra 17 March 2015 (has links)
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Previous issue date: 2015-03-17 / The objective of this study was to measurement of the intraocular pressure (IOP) with Kowa HA-2 tonometer in cats analyzing the calibration, the accuracy and the validation of ambulatory clinical use. For calibration the post-mortem study was accomplished in 10 healthy eyes of 5 cats comparing the ocular manometry with the values of the IOP checked with the tonometer. For evaluation of the accuracy an in vivo study was accomplished in 20 healthy eyes of 10 anesthetized cats being compared the ocular manometry with the IOP obtained with the tonometer. For validation of the ambulatory clinical study of the IOP measurement was accomplished in 78 eyes of 39 healthy cats, in 7 eyes with clinical signs of glaucoma and in 20 eyes with clinical signs of uveitis. The correlation coefficient (r²) between the manometer and the tonometer was 0.993 and the equation of lineal regression was y=0.0915x+0.0878 in postmortem study. In the in vivo study the medium values of IOP in the manometry were 15.6±1.1 mmHg and in the tonometry were 15.5±1.2 mmHg, there was no statistics significant difference between the manometry and the tonometry. In the ambulatory clinical study with healthy cats the medium values of IOP with the tonometer were 15.0±1.5 mmHg, in the eyes with clinical signs of glaucoma were 38,4±8,1 mmHg and in the eyes with clinical signs of uveitis were of 10,4±2,0 mmHg. Therefore, there was a satisfactory correlation and accuracy between the IOP values obtained by direct ocular manometry and the tonometer in question. In the ambulatory clinical study the IOP values obtained with the tonometer were compatible for animals with healthy eyes and with clinical signs of glaucoma and uveitis. So, we can conclude that the Kowa HA-2 tonometer can be used in the routine ophthalmic examination, as it is a practical method for IOP measurement in cats. / O objetivo deste estudo foi mensurar a pressão intraocular (PIO) com o uso do tonômetro Kowa HA-2 em gatos, analisando a calibração, a acurácia e a validação do seu uso clínico ambulatorial. Para calibração foi realizado o estudo post-mortem em 10 olhos sadios de 5 gatos comparando a manometria ocular com os valores da PIO aferida com o tonômetro. Para avaliação de sua acurácia foi realizado um estudo in vivo em 20 olhos sadios de 10 gatos anestesiados comparando-se a manometria ocular com a PIO obtida com o tonômetro. Para validação do seu uso clínico ambulatorial foi realizado um estudo da mensuração da PIO em 78 olhos sadios de 39 gatos, em 7 olhos com sinais clínicos de glaucoma e em 20 olhos com sinais clínicos de uveíte. O coeficiente de correlação (r²) entre o manômetro e o tonômetro Kowa HA-2 foi de 0,993 e a equação de regressão linear foi y=0,0915x+0,0878 no estudo postmortem. No estudo in vivo, os valores médios de PIO na manometria foram de 15,6±1,1 mmHg e na tonometria foram de 15,5±1,2 mmHg não havendo diferença estatística significativa entre a manometria e a tonometria. No estudo ambulatorial com os gatos sadios, os valores médios de PIO com o tonômetro Kowa HA-2 foram 15,0±1,5 mmHg, nos olhos com sinais clínicos de glaucoma foram 38,4±8,1 mmHg e nos olhos com sinais clínicos de uveíte foram 10,4±2,0 mmHg. Houve, portanto, correlação e acurácia satisfatória entre os valores de PIO com a manometria e o tonômetro em questão. No estudo ambulatorial os valores de PIO obtidos com o tonômetro foram compatíveis para animais com olhos sadios e com sinais clínicos de glaucoma e uveíte. Desta maneira, podemos concluir que o tonômetro Kowa HA-2 pode ser empregado no exame oftálmico de rotina, pois trata-se de um método prático na aferição da PIO em gatos.
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