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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.
391

Interactive Training System for Medical Ultrasound

Banker, Christian John 17 February 2009 (has links)
Ultrasound is an effective imaging modality because it is safe, unobtrusive and portable. However, it is also very operator-dependent and significant skill is required to capture quality images and properly detect abnormalities. Training is an important part of ultrasound, but the limited availability of training courses presents a significant hindrance to the use of ultrasound being used in additional settings. The goal of this work was to design and implement an interactive training system to help train and evaluate sonographers. The Interactive Training System for Medical Ultrasound is an inexpensive, software-based training system in which the trainee scans a lifelike manikin with a sham transducer containing a 6 degree of freedom tracking sensor. The observed ultrasound image is generated from a pre-stored 3D image volume and is controlled interactively by the sham transducer's position and orientation. Based on the selected 3D volume, the manikin may represent normal anatomy, exhibit a specific trauma or present a given physical condition. The training system provides a realistic scanning experience by providing an interactive real-time display with adjustable image parameters such as scan depth, gain, and time gain compensation. A representative hardware interface has been developed including a lifelike manikin and convincing sham transducers, along with a touch screen user interface. Methods of capturing 3D ultrasound image volumes and stitching together multiple volumes have been evaluated. System performance was analyzed and an initial clinical evaluation was performed. This thesis presents a complete prototype training system with advanced simulation and learning assessment features. The ultrasound training system can provide cost-effective and convenient training of physicians and sonographers. This system is an innovative approach to training and is a powerful tool for training sonographers in recognizing a wide variety of medical conditions.
392

An Inertial-Optical Tracking System for Quantitative, Freehand, 3D Ultrasound

Goldsmith, Abraham Myron 16 January 2009 (has links)
Three dimensional (3D) ultrasound has become an increasingly popular medical imaging tool over the last decade. It offers significant advantages over Two Dimensional (2D) ultrasound, such as improved accuracy, the ability to display image planes that are physically impossible with 2D ultrasound, and reduced dependence on the skill of the sonographer. Among 3D medical imaging techniques, ultrasound is the only one portable enough to be used by first responders, on the battlefield, and in rural areas. There are three basic methods of acquiring 3D ultrasound images. In the first method, a 2D array transducer is used to capture a 3D volume directly, using electronic beam steering. This method is mainly used for echocardiography. In the second method, a linear array transducer is mechanically actuated, giving a slower and less expensive alternative to the 2D array. The third method uses a linear array transducer that is moved by hand. This method is known as freehand 3D ultrasound. Whether using a 2D array or a mechanically actuated linear array transducer, the position and orientation of each image is known ahead of time. This is not the case for freehand scanning. To reconstruct a 3D volume from a series of 2D ultrasound images, assumptions must be made about the position and orientation of each image, or a mechanism for detecting the position and orientation of each image must be employed. The most widely used method for freehand 3D imaging relies on the assumption that the probe moves along a straight path with constant orientation and speed. This method requires considerable skill on the part of the sonographer. Another technique uses features within the images themselves to form an estimate of each image's relative location. However, these techniques are not well accepted for diagnostic use because they are not always reliable. The final method for acquiring position and orientation information is to use a six Degree-of-Freedom (6 DoF) tracking system. Commercially available 6 DoF tracking systems use magnetic fields, ultrasonic ranging, or optical tracking to measure the position and orientation of a target. Although accurate, all of these systems have fundamental limitations in that they are relatively expensive and they all require sensors or transmitters to be placed in fixed locations to provide a fixed frame of reference. The goal of the work presented here is to create a probe tracking system for freehand 3D ultrasound that does not rely on any fixed frame of reference. This system tracks the ultrasound probe using only sensors integrated into the probe itself. The advantages of such a system are that it requires no setup before it can be used, it is more portable because no extra equipment is required, it is immune from environmental interference, and it is less expensive than external tracking systems. An ideal tracking system for freehand 3D ultrasound would track in all 6 DoF. However, current sensor technology limits this system to five. Linear transducer motion along the skin surface is tracked optically and transducer orientation is tracked using MEMS gyroscopes. An optical tracking system was developed around an optical mouse sensor to provide linear position information by tracking the skin surface. Two versions were evaluated. One included an optical fiber bundle and the other did not. The purpose of the optical fiber is to allow the system to integrate more easily into existing probes by allowing the sensor and electronics to be mounted away from the scanning end of the probe. Each version was optimized to track features on the skin surface while providing adequate Depth Of Field (DOF) to accept variation in the height of the skin surface. Orientation information is acquired using a 3 axis MEMS gyroscope. The sensor was thoroughly characterized to quantify performance in terms of accuracy and drift. This data provided a basis for estimating the achievable 3D reconstruction accuracy of the complete system. Electrical and mechanical components were designed to attach the sensor to the ultrasound probe in such a way as to simulate its being embedded in the probe itself. An embedded system was developed to perform the processing necessary to translate the sensor data into probe position and orientation estimates in real time. The system utilizes a Microblaze soft core microprocessor and a set of peripheral devices implemented in a Xilinx Spartan 3E field programmable gate array. The Xilinx Microkernel real time operating system performs essential system management tasks and provides a stable software platform for implementation of the inertial tracking algorithm. Stradwin 3D ultrasound software was used to provide a user interface and perform the actual 3D volume reconstruction. Stradwin retrieves 2D ultrasound images from the Terason t3000 portable ultrasound system and communicates with the tracking system to gather position and orientation data. The 3D reconstruction is generated and displayed on the screen of the PC in real time. Stradwin also provides essential system features such as storage and retrieval of data, 3D data interaction, reslicing, manual 3D segmentation, and volume calculation for segmented regions. The 3D reconstruction performance of the system was evaluated by freehand scanning a cylindrical inclusion in a CIRS model 044 ultrasound phantom. Five different motion profiles were used and each profile was repeated 10 times. This entire test regimen was performed twice, once with the optical tracking system using the optical fiber bundle, and once with the optical tracking system without the optical fiber bundle. 3D reconstructions were performed with and without the position and orientation data to provide a basis for comparison. Volume error and surface error were used as the performance metrics. Volume error ranged from 1.3% to 5.3% with tracking information versus 15.6% to 21.9% without for the version of the system without the optical fiber bundle. Volume error ranged from 3.7% to 7.6% with tracking information versus 8.7% to 13.7% without for the version of the system with the optical fiber bundle. Surface error ranged from 0.319 mm RMS to 0.462 mm RMS with tracking information versus 0.678 mm RMS to 1.261 mm RMS without for the version of the system without the optical fiber bundle. Surface error ranged from 0.326 mm RMS to 0.774 mm RMS with tracking information versus 0.538 mm RMS to 1.657 mm RMS without for the version of the system with the optical fiber bundle. The prototype tracking system successfully demonstrated that accurate 3D ultrasound volumes can be generated from 2D freehand data using only sensors integrated into the ultrasound probe. One serious shortcoming of this system is that it only tracks 5 of the 6 degrees of freedom required to perform complete 3D reconstructions. The optical system provides information about linear movement but because it tracks a surface, it cannot measure vertical displacement. Overcoming this limitation is the most obvious candidate for future research using this system. The overall tracking platform, meaning the embedded tracking computer and the PC software, developed and integrated in this work, is ready to take advantage of vertical displacement data, should a method be developed for sensing it.
393

An Injury-Mimicking Ultrasound Phantom as a Training Tool for Diagnosis of Internal Trauma

Rowan, Matthew Ivan 20 December 2006 (has links)
"Ultrasound phantoms that mimic injury are training devices that can emulate pre- and post-injury conditions within specific regions of human anatomy. They have the potential to be useful tools for teaching medical personnel how to recognize trauma conditions based on ultrasound images. This is particularly important because the increased use of portable ultrasound systems allows earlier diagnosis of internal trauma at locations such as traffic accidents, earthquakes, battlefields and terrorist attacks. A physical injury mimicking ultrasound phantom of the peritoneal cavity was constructed that mimicked the ultrasonic appearance of internal bleeding. Bleeding was simulated by injecting 600 mL of fluid of varying densities into the bulk of the phantom and comparing the ultrasonic appearance to before bleeding was simulated. The physical phantom was used to investigate whether or not the density of the injected fluid had any influence on the increase of inter-organ fluid volumes. The physical phantom was imaged in 3D with a 4.5 MHz phased array transducer, and two fluid volumes were segmented using the segmentation software ITK-SNAP. The 3D image representation of the phantom showed a difference qualitatively and quantitatively between pre-injury and post-injury conditions. Qualitatively, the physical model was analyzed. These specific criteria were analyzed within each image: 1) the number of individual organs that are present, 2) the number of other organs that each individual organ touches, 3) the appearance of fluid between the organs and the scanning membrane and 4) the merging of two separate fluid pockets. Using a Wilcoxon Rank-Sum test, a statistically significant difference was shown to exist between pre-injury and post-injury ultrasound images with a 95% level of confidence. Quantitatively, a Chi-Squared test was used to show that the volume of fluid between adjacent organs, calculated by ITK-SNAP, had no dependence on the density of the injected fluid. Furthermore, using a one-tailed T-test, there was at least a 99.9% confidence that the inter-organ volume estimations for the pre-injury and post-injury configurations were statistically different. As a final means of evaluation, the experimental phantom was taken to Harvard Medical School in November 2006 and analyzed by ultrasonographers. The doctors were very excited about its potential uses and found other interesting characteristics that the phantom was not designed for. In addition to modeling the appearance of an injected fluid volume, visualization of fluid flowing into the phantom, modeling the appearance of air in the inter-peritoneal space and simulating a surgical tool or bandage being accidentally left inside the patient could be modeled as well. The injury mimicking phantom was also modeled numerically, using ADINA finite element software. Using the same external dimensions as the experimental model, the numerical model showed that for physiologically unrealistic, very high fluid injection densities, the displacement of the organs had no statistical dependence on the density of the injected fluid, using an acceptance criterion of: P-value < 0.05. This was confirmed using an F-test of the average organ phantom tip displacement tabulated at several different times during simulation. The P-value obtained for analyzing the average tip displacement was 0.0506. However, a plot of the mass ratio, an expression of how the injected fluid has dispersed into the bulk of the phantom, showed that an unrealistically high fluid injection density had a different mass ratio profile than the other fluid injection densities that were simulated. This F-test revealed a strong indication, P-value = 0.0069, that the very high density caused a different fluid dispersion pattern. The numerical phantom offered a distinct advantage over the experimental model in that the dispersion of the injected fluid could be modeled numerically but not observed experimentally. Modeling the phantom numerically had some disadvantages. The numerical model had to have a large gap between adjacent organs. This had to occur because the contact algorithm within ADINA is incapable of modeling dynamic contact when fluid-structure interactions are modeled. This led to a volume fraction representation of the solid domain that was too low compared with the experimental model and what is found anatomically. For future iterations of the injury mimicking phantom, the numerical model will be used to help design the physical phantoms."
394

Computer vision-based tracking and feature extraction for lingual ultrasound

Al-Hammuri, Khalid 30 April 2019 (has links)
Lingual ultrasound is emerging as an important tool for providing visual feedback to second language learners. In this study, ultrasound videos were recorded in sagittal plane as it provides an image for the full tongue surface in one scan, unlike the transverse plane which provides an information for small portion of the tongue in a single scan. The data were collected from five Arabic speakers as they pronounced fourteen Arabic sounds in three different vowel contexts. The sounds were repeated three times to form 630 ultrasound videos. The thesis algorithm was characterized by four steps. First: denoising the ultrasound image by using the combined curvelet transform and shock filter. Second: automatic selection of the tongue contour area. Third: tongue contour approximation and missing data estimation. Fourth: tongue contour transformation from image space to full concatenated signal and features extraction. The automatic tongue tracking results were validated by measuring the mean sum of distances between automatic and manual tongue contour tracking to give an accuracy of 0.9558mm. The validation for the feature extraction showed that the average mean squared error between the extracted tongue signature for different sound repetitions was 0.000858mm, which means that the algorithm could extract a unique signature for each sound and across different vowel contexts with a high degree of similarity. Unlike other related works, the algorithm showed an efficient and robust approach that could extract the tongue contour and the significant feature for the dynamic tongue movement on the full video frames, not just on the significant single and static video frame as used in the conventional method. The algorithm did not need any training data and had no limitation for the video size or the frame number. The algorithm did not fail during tongue extraction and did not need any manual re-initialization. Even when the ultrasound image recordings missed some tongue contour information, the thesis approach could estimate the missing data with a high degree of accuracy. The usefulness of the thesis approach as it can help the linguistic researchers to replace the manual tongue tracking by an automated tracking to save the time, then extracts the dynamics features for the full speech behavior to give better understanding of the tongue movement during the speech to develop a language learning tool for the second language learners. / Graduate
395

Traitement des tumeurs cérébrales par ultrasons focalisés de haute intensité - sur un modèle tumoral greffé chez le rat / High intensity focused ultrasound therapy for brain tumors - in a rat brain tumor model.

Dervishi, Elvis 24 September 2014 (has links)
La thérapie par faisceaux ultrasonores focalisés de forte intensité (HIFU / High Intensity Focused Ultrasound) est une nouvelle technique d’ablation tissulaire, fondée sur la focalisation de faisceaux ultrasonores de forte intensité pour réaliser une élévation de température capable de créer une nécrose thermique. Le cerveau a été jusqu’à présent peu accessible aux ultrasons car il est protégé par la boîte crânienne. Mais de nouvelles techniques de focalisation par correction des aberrations des faisceaux ultrasonores laissent espérer des applications prochaines en intracrânien, où l’HIFU pourrait constituer une intéressante alternative à la chirurgie et à la radiothérapie stéréotaxique. Le but général de ce travail a été de tester la thérapie HIFU contrôlée par Imagerie de Résonance Magnétique (IRM) pour le traitement des tumeurs cérébrales dans un modèle petit animal in vivo de tumeur cérébrale. Nous espérons ainsi fournir des apports sur la thérapie HIFU et ses effets biologiques sur le cerveau et les tumeurs cérébrales, connaissances nécessaires avant de passer à des études cliniques chez l’homme. Le plan de ce travail est le suivant : 1) développement d’un protocole de thérapie HIFU contrôlé par IRM sur le cerveau sain et sur un modèle de tumeur RG2 greffée en intracérébral chez le rat ; 2) étude des effets biologiques de l’HIFU par l’IRM et l’examen anatomo-pathologique sur le tissu cérébral sain et la tumeur RG2 en intracérébral, montrant une sensibilité variable des tissus à l’hyperthermie ; 3) étude de sécurité (tolérance et effets indésirables), démonstration d’efficacité sur la tumeur RG2 (ralentissement de l’évolution tumorale et augmentation de la survie des animaux traités). En conclusion, l’HIFU a montré sa précision et son efficacité dans le traitement de la tumeur RG2 greffée en intracérébral chez le rat. Cette technique n’est cependant pas exempte de complications, notamment un œdème périlésionnel et des hémorragies intratumorales. / High Intensity Focused Ultrasound (HIFU) therapy is an innovative approach for tissue ablation, based on high intensity focused ultrasound beams. At focus, HIFU induces a temperature elevation and the tissue can be thermally destroyed. For transcranial brain therapy, the skull bone is a major limitation but new adaptive techniques for focusing ultrasound through the skull are underway and in the near future HIFU therapy could be an interesting alternative to brain surgery and radiotherapy.The overall aim of this work is to test HIFU therapy guided by Magnetic Resonance Imaging (MRgHIFU) for the treatment of brain tumors in an in vivo brain tumor model in rodent in order to provide inputs for future regulatory approval for clinical trial with a clinical prototype. In this work: 1) a dedicated system for transcranial MRgHIFU in an in vivo rat brain tumor model was developed, and a full protocol was applied in healthy brain tissue of rats and in transplanted tumors; 2) the biological effects of HIFU therapy was evaluated using MRI and histology in healthy brain tissue and in RG2 brain tumor, showing a different tissue sensibility for hyperthermia; 3) tolerance and side effects were investigated and the treatment was shown to improve the animal survival time by 50%. In conclusion, HIFU therapy has proved its accuracy and efficacy in the treatment of the RG2 brain tumor transplanted intracerebral in rats. However this technique is not free of complications, in particular edema and hemorrhages.
396

Simulação da vascularização através da cortical óssea de mandíbulas suínas por meio da ultrassonografia modo B e Doppler / Simulation of vasularization of the cortical bone of the jaw swine by using ultrasound B mode and Doppler

Baladi, Marina Gazzano 06 July 2011 (has links)
A ultrassonografia é um método de diagnóstico que aproveita o eco produzido pelo som para ver, em tempo real, as sombras produzidas pelas estruturas e órgãos. Os aparelhos de ultrassom em geral utilizam uma frequência próxima de 1MHz. A ultrassonografia permite ainda, pelo modo Doppler, conhecer o sentido e a velocidade de fluxos sanguíneos. Por não utilizar radiação, ionizante, é um método inócuo e barato. A avaliação da circulação nos tecidos corpóreos pode indicar o tipo de lesão ou, nos casos de cirurgia, mostrar a posição de artérias presentes na região. Neste trabalho foi de finalidade apresentar a espessura óssea ideal para a captação do sinal Doppler, utilizando uma amostra de 10 mandíbulas suínas maceradas, avaliando-se a região dos terceiros molares (de ambos os lados, direito e esquerdo, totalizando 20 hemimandíbulas). As mandíbulas suínas foram preparadas para receber e adaptar tubos de CFlex conectados a um capilar de vidro e a uma bomba propulsora, por onde passava o líquido, simulando a vascularização sanguínea. Foram tomadas diferentes medidas de espessura óssea, sendo possível, em algumas hemimandíbulas, captarmos sinais. Na dependência da espessura da cortical óssea, que em nosso trabalho estudamos no intervalo de 0,2 a 1,0mm, possibilitou-se a captação de sinais, no modo B e Doppler, referentes ao simulador da vascularização. A ultrassonografia é um recurso imaginológico com aplicabilidade cada vez maior na área da Saúde, em particular no estudo da vascularização intraóssea. / Ultrasound is an image diagnostic method that takes advantage of the echo produced by sound to see in real time, the shadows produced by the structures and organs. Ultrasound machines typically use a frequency of about 1MHz. The ultrasound also enables, by the Doppler mode, to read the direction and velocity of blood flow. As we do not use radiation, ionizing radiation, it is a harmless and inexpensive method. The evaluation of the circulation in body tissues may indicate the type of injury, or in cases of surgery, it shows the position of the arteries in the region. This study aimed to present the ideal bone thickness to capture the Doppler signal using a sample of 10 macerated pig jaws, assessing the region of the third molars (on both sides, right and left, totaling 20 hemijwas). The pig jaws were prepared to accept and adapt CFlex tubes connected to a glass capillary and a pump, through which liquid flowed, simulating the blood vasculature. Different measures of bone thickness, were taken and in some hemijaws signals were possible to be taken. Depending on the thickness of cortical bone, which in our work we have studied in the range 0,2 to 1,0 mm, made it possible to capture signals in B mode and Doppler simulator for the vasculature. Ultrasound is a resource imaginologic increasing applicability in healthcare, particularly in the study of intraosseous vascularity.
397

Fetal responsiveness to auditory and tactile stimulation

Marx, Viola January 2018 (has links)
The aim of this thesis was to examine fetal behavioural responses to auditory and tactile stimulation. Responses were examined for the second- and third-trimester fetuses (second-trimester ≤ 27 gestational weeks (wGA), third- trimester >27 wGA), in both experiments, respectively. Experiment 1 of this thesis examined fetal behavioural responses to the mother’s recorded and live voice, contrasting findings to an environmental sound and silent control conditions. Behavioural responses of 30 fetuses trimester (20-33 wGA, N = 13 in the 2nd and N = 17 in the 3rd trimester) Were examined in the following conditions were explored: (1) mother’s live, (2) and recorded voice, (3) an environmental sound, and (4) a silent control condition. Findings showed the strongest responses to maternal sounds as well as differential responses between gestational age groups. Younger fetuses displayed an arousal response to maternal voice, whereas third-trimester fetuses displayed an orientating response. The aim of Experiment 2 was to examine whether fetuses can differentiate between different human sources of tactile stimulation of the maternal abdomen. Behavioural responses of 28 fetuses (20-33 wGA, N = 15 in the 2nd and N = 13 in the 3rd trimester) were examined across four conditions: (1) mother’s, (2) father’s, and (3) stranger’s touch, as well as a (4) silent control condition. Differential responses to the tactile stimulation were found, especially in reaching of the uterine wall, and self- touch across the four conditions. Third- trimester fetuses touched the uterus wall for significantly longer than fetuses in the second-trimester. The strongest responses were found to the mother’s touch. Further differential responses were found between age groups, with third-trimester fetuses clearly differentiating between different sources of tactile stimulation, while second-trimester fetuses hardly showed differentiated responses. It is suggested that maturational differences in both experiments are due to the fetal development of the central nervous system, and might indicate the emergence of a proprioceptive self-awareness by the 3rd trimester.
398

Evaluation of harmonic motion elastography and acousto-optic imaging for monitoring lesion formation by high intensity focused ultrasound

Draudt, Andrew Bruce January 2012 (has links)
Malignant or benign tumors may be ablated with high‐intensity focused ultrasound (HIFU). This technique, known as focused ultrasound surgery (FUS), has been actively investigated for decades, but slow to be implemented and difficult to control due to lack of real‐time feedback during ablation. Two methods of imaging and monitoring HIFU lesions during formation were implemented simultaneously, in order to investigate the efficacy of each and to increase confidence in the detection of the lesion. The first, Acousto‐Optic Imaging (AOI) detects the increasing optical absorption and scattering in the lesion. The intensity of a diffuse optical field in illuminated tissue is mapped at the spatial resolution of an ultrasound focal spot, using the acousto‐optic effect. The second, Harmonic Motion Imaging (HMI), detects the changing stiffness in the lesion. The HIFU beam is modulated to force oscillatory motion in the tissue, and the amplitude of this motion, measured by ultrasound pulse‐echo techniques, is influenced by the stiffness. Experiments were performed on store‐bought chicken breast and freshly slaughtered bovine liver. The AOI results correlated with the onset and relative size of forming lesions much better than prior knowledge of the HIFU power and duration. For HMI, a significant artifact was discovered due to acoustic nonlinearity. The artifact was mitigated by adjusting the phase of the HIFU and imaging pulses. A more detailed model of the HMI process than previously published was made using finite element analysis. The model showed that the amplitude of harmonic motion was primarily affected by increases in acoustic attenuation and stiffness as the lesion formed and the interaction of these effects was complex and often counteracted each other. Further biological variability in tissue properties meant that changes in motion were masked by sample‐to‐sample variation. The HMI experiments predicted lesion formation in only about a quarter of the lesions made. In simultaneous AOI/HMI experiments it appeared that AOI was a more robust method for lesion detection. / Bernard M. Gordon Center for Subsurface and Imaging Systems (CenSSIS) via the NSF ERC award number EEC‐9986821.
399

AvaliaÃÃo da eficÃcia da ultra-sonografia anorretal tridimensional dinÃmica (ecodefecografia) no diagnÃstico de anorretocele e intussuscepÃÃo retal em mulheres com evacuaÃÃo obstruÃda comparando com a cinedefecografia / Evaluation of the effectiveness of the ultrasound dynamic three-dimensional anorrectal (ecodefecography) in the anorrectocele diagnosis and rectal intussuscepcion in women with obstructed evacuation comparing with the cinedefecography

FlÃvio Roberto Santos e Silva 21 December 2006 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A sÃndrome de evacuaÃÃo obstruÃda ocorre com maior frequÃncia em mulheres entre a quarta e a quinta dÃcada de vida afetando progressivamente a qualidade de vida destas pacientes. O objetivo à demonstrar a eficÃcia da ultra-sonografia anorretal tridimensional dinÃmica (ecodefecografia) no diagnÃstico de anorretocele e intussuscepÃÃo retal em mulheres com evacuaÃÃo obstruÃda, comparando com a cinedefecografia. Foi realizado um estudo prospectivo com 30 pacientes com queixas de evacuaÃÃo obstruÃda (constipaÃÃo crÃnica ou disquezia refratÃria a medicaÃÃes) e provenientes do ServiÃo de Coloproctologia do Hospital UniversitÃrio Walter CantÃdio da Universidade Federal do CearÃ, no perÃodo de abril de a outubro de 2006. A idade mÃdia foi de 47,7 anos, variando de 24 a 79 anos (DP +/- 14,83). Com relaÃÃo à paridade, 5 (16,0 %) pacientes sÃo nulÃparas, duas ( 6,0 %) sÃo primÃparas e 23 (76,0 %) submeteram-se a dois ou mais partos. A mÃdia de concepÃÃes por paciente foi de 3,33 partos vaginais (0 a 11 partos) (DP +/- 3.30) e partos cesÃreos com mÃdia de 0,26 partos (0 a 3 partos) (DP+/- 0,63). Baseando-se no Sistema de ClassificaÃÃo da Cleveland Clinic para ConstipaÃÃo (SCCC-C), o escore mÃdio foi 14 pontos com variaÃÃo de 7 a 25 pontos (DP +/- 4,66). Os parÃmetros avaliados incluÃram dados de histÃria clÃnica, exame fÃsico, achados da cinedefecografia (CD) e da ecodefecografia (ED). Seis pacientes foram consideradas normais na cinedefecografia e 5 pacientes na ecodefecografia. Durante a ED, observou-se deslocamento posterior da vagina durante o esforÃo evacuatÃrio, permanecendo ao mesmo nÃvel ao fim do esforÃo. As mediÃÃes realizadas entre as linhas foram iguais a zero. Foram identificadas 5 pacientes com anorretocele grau I, 7 com grau II e 12 com grau III à cinedefecografia enquanto a ecodefecografia diagnosticou 5 pacientes com grau I, 7 pacientes com grau II e 13 pacientes com grau III. Houve somente uma discordÃncia pois uma paciente apresentou-se normal à CD enquanto a ED demonstrou a presenÃa de anorretocele grau III (Kappa = 0,902, p<0,001). Foi identificada intussuscepÃÃo retal em 5 pacientes à CD enquanto a ED confirmou estes achados e identificou esta alteraÃÃo anÃtomo-funcional em mais 7 pacientes (Kappa = 0.462, p< 0,05) e demonstrando equivalÃncia moderada entre os exames. Conclui-se que a ecodefecografia à um mÃtodo eficaz para avaliar pacientes com evacuaÃÃo obstruÃda pois apresentou resultados semelhantes à cinedefecografia na identificaÃÃo de anorretocele e superior no diagnÃstico da intussuscepÃÃo, possibilitando ainda quantificar a anorretocele, à um exame pouco invasivo, bem tolerado, demonstra as estruturas anatÃmicas envolvidas na defecaÃÃo e nÃo expÃe as pacientes à radiaÃÃo
400

Ultra-sonografia transvaginal com dopplervelocimetria na monitorização endometrial durante o tratamento hormonal na pós-menopausa / Transvaginal ultrasound with Dopplervelocimetry for endometrial monitoring during hormone therapy in post-menopause

Rubens Brocco Dolce 20 September 2006 (has links)
INTRODUÇÃO: O tratamento estrogênico isolado e contínuo por seis meses é uma opção no tratamento de sintomas climatéricos. A monitorização endometrial deve ser realizada rotineiramente; nela, a ultra-sonografia (US) e a biópsia uterina têm papel importante. A US e a Dopplervelocimetria também avaliam as mudanças circulatórias uterinas. OBJETIVO: Estudar o comportamento da vascularização uterina e do endométrio em mulheres na pós-menopausa tratadas com estrógeno contínuo por seis meses, seguido de progestógeno isolado por 14 dias, e estabelecer suas relações com a proliferação endometrial. MÉTODO: Estudo clínico, prospectivo e controlado, onde quarenta mulheres na pós-menopausa, sem contraindicações para tratamento hormonal (TH). Foram divididas em dois grupos: Estrógeno e Controle. As do Grupo Estrógeno (GE), n= 24, receberam 50 mcg de estradiol-17 beta (E2) transdérmico, duas vezes por semana, durante seis meses. As mulheres do Grupo Controle (GC), n=16, não receberam TH. Todas realizaram FSH, E2 e glicemia de jejum; US transvaginal; Dopplervelocimetria das artérias uterinas, miometriais e endometriais e biópsia aspirativa de endométrio. O GE repetiu os mesmos exames, com exceção de FSH, E2 e glicemia, no terceiro e no sexto mês de tratamento. No GC, a biópsia do endométrio foi repetida apenas no sexto mês de tratamento. As mulheres do GE utilizaram, ao fim de seis meses, 10 mg de acetato de medroxiprogesterona por dia, durante 14 dias. RESULTADOS: No GE, a resistência vascular das artérias uterinas diminuiu no terceiro e no sexto mês de tratamento. O fluxo miometrial das artérias arqueadas aumentou significantemente no sexto mês de tratamento. O aumento da espessura do endométrio ocorreu de forma significante no terceiro mês. No GE houve hiperplasia endometrial simples e sem atipias em 20,8 % das mulheres. No GE, comparando as mulheres que tiveram proliferação com aquelas que mantiveram a atrofia endometrial, observou-se que, no sexto mês de tratamento, o grupo que apresentou proliferação teve diminuição significante da resistência vascular da artéria uterina esquerda, enquanto no grupo que manteve a atrofia, a resistência vascular aumentou na artéria uterina direita. No GC não ocorreu variação da resistência vascular das artérias uterinas bilaterais; o fluxo miometrial das artérias arqueadas não se modificou e não houve proliferação endometrial. CONCLUSÃO: A terapia estrogênica isolada por seis meses diminuiu a resistência vascular das artérias uterinas bilateralmente. A proliferação endometrial precedeu o aumento de vascularização miometrial. Houve associação entre a proliferação endometrial e a diminuição da resistência vascular na artéria uterina esquerda, no final do sexto mês de tratamento estrogênico / INTRODUCTION: Isolated continuous estrogen therapy for 6 months is an option to manage climacteric symptoms. Endometrial monitoring should be performed as a routine, in which ultrasound and uterine biopsy have an important role. Ultrasound with Dopplervelocimetry also assesses uterine circulatory changes. OBJECTIVE: To study the uterine circulatory changes of women in continuous estrogen therapy for 6 months using Doppler velocimetry and to define correlations with endometrial proliferation. METHOD: Clinical prospective controlled study. Forty menopause women were studied, without contraindications to hormone therapy (HT). They were divided into 2 groups: Estrogen and Control. In the Estrogen Group (EG) n = 24, they were treated with transdermal 50mcg estradiol-17 beta (E2), changed twice a week for 6 months. Women in the Control Group (CG) n=16, were not treated with hormones. They all underwent FSH, E2, fast glucose, transvaginal ultrasound , uterine, myometrial and endometrial artery Dopplervelocimetry and aspiration biopsy of endometrium. The EG repeated the same procedures in months 3 and 6 of treatment. In CG, endometrial biopsy was repeated only in the 6th month of treatment. At the end of treatment, EG women received 10 mg of medroxyprogesterone acetate per day for 14 days. RESULTS: In EG, vascular resistance of uterine arteries reduced in the 3rd and 6th months of treatment. Myometrial flow of arcuate arteries was significantly increased in the 6th month of treatment. Increased endometrial thickness was significant in the 3rd month. In EG, the authors detected simple endometrial hyperplasia without atypias in 20.8% of the subjects. In EG, in the 6th month of treatment, upon comparing women who had proliferation and those who maintained the endometrial atrophy, we observed that the group that presented proliferation had significant reduction of vascular resistance of left uterine artery, whereas the group that maintained atrophy had increase in vascular resistance of right uterine artery. In CG, there was no vascular resistance modification, no myometrial flow diference and no endometrial proliferation. CONCLUSION: Isolated estrogen therapy for 6 months reduced vascular resistance of bilateral uterine arteries. Morphological affections to the endometrium preceded myometrial vascular abnormalities. There was association of endometrial proliferation and reduction of vascular resistance of the left uterine artery in the 6th month of estrogen treatment

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