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Endocavitary applicator of therapeutic ultrasound integrated with RF receiver coil for high resolution MRI-controlled thermal therapyRata, Mihaela 15 December 2009 (has links) (PDF)
This thesis presents technical and methodological developments aiming tooffer a viable alternative for the treatment of digestive cancers (rectum and esophagus). Compared to the standard methods of therapy, the high intensity contact ultrasound guided by MRI is a less invasive approach. MRI offers 2 advantages: good spatial resolution, and real-time temperature control. This treatment method requires efficacy and safety. Three prototypes of RF coil integrated with ultrasound transducers were built in order to increase the spatial and temporal resolution ofthe MR images, and the accuracy of the temperature measurement. The integrated coils showed a better sensitivity compared to a standard extracorporeal coil. Anatomical (voxel 0.4x0.4x5 mm3)and thermometry (voxel 0.75x0.75x8 mm3, 2s/image) high resolution MR images were acquired in-vivo. The temperature was measured, within a radius of 20 mm from the balloon, with a standard deviation <1°C. The flow artifacts caused by the water circulating inside the cooling balloon could be shifted out of the region of interest. The temperature evolution was controlled automatically, at different depths, with one control point per beam. The controller showed a good accuracy during in-vivo experiments (standard deviation less than 5%). The phased-arrayultra sound transducer permits the successive activation of multiple beams during the same dynamic of sonication. Simulations were conducted in order to offer an optimal treatment planning for a defined tumor. A new design of ultrasound transducer with 256 elements with revolution symmetry, based on a natural geometrical focalization, was proposed.
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Complicated gallstone disease in Sweden 1988-2006 : a register studySandzén, Birger January 2011 (has links)
Background The gallstone prevalence in the western world is 10-20%. Most gallstones are silent, but symptoms and complications appear in 20-40%. The incidence of symptom development in patients with silent gallstones is 2-4% per year. The indication for surgical (including endoscopic) treatment of gallstones is symptoms of certain magnitude, and no contraindications. During the past three decades an intense technical development in imaging (ultrasound, computerised tomography and magnetic resonance imaging), endoscopic therapy, and surgery has taken place. The aim of this thesis is to scrutinize changes in management of complicated gallstone disease on a population-based level, using national register data. Have the new methods improved the treatment of acute pancreatitis, common bile duct stones and acute gallbladder disease? Methods Data is collected from National Patient Register (NPR) run by The Swedish National Board of Health and Welfare. NPR collects discharge data from every admission from every Swedish hospital. Mortality is calculated as standardised mortality ratio (SMR) using age-, gender-, and calendar year specific survival estimates. We have studied both general trends in admissions and treatment alternatives and outcomes in defined patient cohorts. Length of hospital stay, readmission, and mortality has been used as proxy indicators of the effectiveness of treatment strategies used. Results During the study period mortality in acute pancreatitis (SMR within 90 days of admission) improved and hospital stay for all patients with acute pancreatitis decreased. Cholecystectomy rate at or shortly after index stay for mild acute biliary pancreatitis increased from 14.5 % to 22.7 %. Of all patients with acute pancreatitis 68.4 % of the patients had no aetiological diagnosis in the register. The incidence of bile duct interventions increased 27.8% from 1988 through 2006. The favoured treatment of bile duct stones changed from open choledocholithectomy to endoscopic sphincterotomy with stone extraction during the same period. However, in 2006, still 19.6% of bile duct interventions for stones were performed as choledochotomy and in the great majority of these cases as open surgery. This indicates a continuing need of education in open bile duct surgery. Mean hospital stay for treatment of common bile duct stones decreased significantly (4.5 days) during the period studied. The mortality (SMR) diminished although without statistical significance during the time period, and there was no significant difference in SMR between choledochotomy and endoscopic sphincterotomy. For acute gallbladder disease a moderate increase of admissions occurred from 1988 through 2006. The relation between acute cholecystectomies versus all cholecystectomies did not change during this period. Of all patients admitted with acute gallbladder disease 32.3 % were cholecystectomised during their first hospital stay, whereas 20.3 % underwent elective cholecystectomy and 6.1 % emergency cholecystectomy within two years of first admission. 41.4 % of patients were not operated on for gallbladder disease within two years of first admission with this diagnosis. Mortality from first admission and 90 days onwards was elevated three-fold during the entire period without time trend, without statistical difference between age groups, and between patients who had cholecystectomy at first admission or later. Conclusion During the audit period treatment of acute pancreatitis improved. However, etiological classification and timing of cholecystectomy in mild acute biliary pancreatitis fell below accepted guidelines. Interventions on the common bile duct for gallstone disease increased significantly. Common bile duct clearance has been separated from cholecystectomy, and cholecystectomy often not done. Only one third of all patients with acute gallbladder disease underwent cholecystectomy at first admission. There is room for improvement in treatment of complicatedgallstone disease, and, gallstone surgeons still need good knowledge in open biliary surgery.
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Nonlinear Interactive Source-filter Model For Voiced SpeechKoc, Turgay 01 October 2012 (has links) (PDF)
The linear source-filter model (LSFM) has been used as a primary model for speech processing
since 1960 when G. Fant presented acoustic speech production theory. It assumes
that the source of voiced speech sounds, glottal flow, is independent of the filter, vocal tract.
However, acoustic simulations based on the physical speech production models show that,
especially when the fundamental frequency (F0) of source harmonics approaches to the first
formant frequency (F1) of vocal tract filter, the filter has significant effects on the source due
to the nonlinear coupling between them. In this thesis, as an alternative to linear source-filter
model, nonlinear interactive source-filter models are proposed for voiced speech.
This thesis has two parts, in the first part, a framework for the coupling of the source and the
filter is presented. Then, two interactive system models are proposed assuming that glottal
flow is a quasi-steady Bernoulli flow and acoustics in vocal tract is linear. In these models,
instead of glottal flow, glottal area is used as a source for voiced speech. In the proposed interactive
models, the relation between the glottal flow, glottal area and vocal tract is determined
by the quasi-steady Bernoulli flow equation. It is theoretically shown that linear source-filter
model is an approximation of the nonlinear models. Estimation of ISFM&rsquo / s parameters from only speech signal is a nonlinear blind deconvolution problem. The problem is solved by a
robust method developed based on the acoustical interpretation of the systems. Experimental
results show that ISFMs produce source-filter coupling effects seen in the physical simulations
and the parameter estimation method produce always stable and better performing
models than LSFM model. In addition, a framework for the incorporation of the source-filter
interaction into classical source-filter model is presented. The Rosenberg source model is extended
to an interactive source for voiced speech and its performance is evaluated on a large
speech database. The results of the experiments conducted on vowels in the database show
that the interactive Rosenberg model is always better than its noninteractive version.
In the second part of the thesis, LSFM and ISFMs are compared by using not only the speech
signal but also HSV (High Speed Endocopic Video) of vocal folds in a system identification
approach. In this case, HSV and speech are used as a reference input-output data for
the analysis and comparison of the models. First, a new robust HSV processing algorithm is
developed and applied on HSV images to extract the glottal area. Then, system parameters
are estimated by using a modified version of the method proposed in the first part. The experimental
results show that speech signal can contain some harmonics of the fundamental
frequency of the glottal area other than those contained in the glottal area signal. Proposed
nonlinear interactive source-filter models can generate harmonics components in speech and
produce more realistic speech sounds than LSFM.
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Risikofaktoren für Blutungskomplikationen nach ÖsophagusvarizenligaturGrothaus, Johannes 09 July 2012 (has links) (PDF)
Esophageal varices are expanded veins of the submucosa that develop in patients with portal hypertension. They develop as collaterals between the portal vein and the superior vena cava. Varices are seen when the HPVG rises >12mmHG and can lead to a life-threatening bleeding episode. Endoscopic band ligation (EBL) is the treatment of choice of acute variceal bleeding. It is also performed for primary and secondary prophylaxis of bleeding from esophageal varices. After EBL, patients are at risk of postinterventional bleeding. Therefore, patients are often hospitalized until endoscopy proves all applied ligation bands have dropped off. At present, there is no standardized algorithm for surveillance of patients after EBL. Furthermore, risk factors for bleeding complications after EBL are poorly evaluated. The available studies mostly investigated patient collectives .after endoscopic sclerotherapy. The aim of this study was to investigate bleeding behaviour after EBL, to make recommendations for in- and out-patient surveillance after EBL and to analyze independent risk factors for bleeding complications after EBL.
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Unterschiede im Blutungsverhalten nach ÖsophagusvarizenligaturPetrasch, Florian 20 October 2011 (has links) (PDF)
Background: Endoscopic band ligation (EBL) is generally accepted as the treatment of choice for bleeding from
esophageal varices. It is also used for secondary prophylaxis of esophageal variceal hemorrhage. However, there is
no data or guidelines concerning endoscopic control of ligation ulcers. We conducted a retrospective study of EBL
procedures analyzing bleeding complications after EBL.
Methods: We retrospectively analyzed data from patients who underwent EBL. We analyzed several data points,
including indication for the procedure, bleeding events and the time interval between EBL and bleeding.
Results: 255 patients and 387 ligation sessions were included in the analysis. We observed an overall bleeding rate
after EBL of 7.8%. Bleeding events after elective treatment (3.9%) were significantly lower than those after
treatment for acute variceal hemorrhage (12.1%). The number of bleeding events from ligation ulcers and variceal
rebleeding was 14 and 15, respectively. The bleeding rate from the ligation site in the group who underwent
emergency ligation was 7.1% and 0.5% in the group who underwent elective ligation. Incidence of variceal
rebleeding did not vary significantly. Seventy-five percent of all bleeding episodes after elective treatment occurred
within four days after EBL. 20/22 of bleeding events after emergency ligation occured within 11 days after
treatment. Elective EBL has a lower risk of bleeding from treatment-induced ulceration than emergency ligation.
Conclusions: Patients who underwent EBL for treatment of acute variceal bleeding should be kept under medical
surveillance for 11 days. After elective EBL, it may be reasonable to restrict the period of surveillance to four days
or even perform the procedure in an out-patient setting.
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A biomechanical study of top screw pullout in anterior scoliosis correction constructsMayo, Andrew January 2007 (has links)
Top screw pullout is a significant problem in anterior scoliosis correction, with rates of 5-15% reported in the literature. The Mater Misericordiae Hospital in Brisbane currently has a series of 125 patients with scoliosis treated by thoracoscopic anterior fusion, instrumentation and correction between April 2000 and August 2007. In this series 11 top screws are known to have pulled out (a rate of 8.8%), with six occurring in the first week, and all within 6 weeks, suggesting that the problem is one of excessive static force rather than fatigue.
This thesis describes a biomechanical investigation into the mechanics of vertebral body screw pullout in anterior scoliosis surgical constructs. Previous biomechanical studies of vertebral body screws have evaluated their resistance to either straight pullout or cephalo-caudad compression forces, however the aim of this study was to assess screw resistance to more realistic loading conditions, namely pullout of initially angled screws, and pullout where the motion path is an arc rather than a straight axial pullout, as would be expected in a single rod anterior construct.
The first series of experiments involved straight and angled pullout tests using synthetic bone. In the angled tests, both locked and free-to-pivot configurations were tested. The second series of experiments tested the effect of cephalo-caudad pre-compression (the actual deformity correction step performed during surgery) on subsequent axial pullout strength. A third series of experiments performed arc pullouts using synthetic bone, and the final series of experiments tested the pullout resistance of a newly proposed screw position configuration against the standard screw positioning using ovine lumbar vertebrae.
Synthetic bone testing revealed that for initially angled pullout, resistance is greatest as the screw angle approaches 0 (ie a direct axial pullout). Cephalo-caudad pre-compression reduced subsequent pullout strength for cases where a staple was not used under the screw head, but if a staple was used the pre-compression did not decrease pullout force significantly. Arc pullout resistance was greatest when the screw was angled at 10 cephalad, and the mean pullout strength for the proposed screw configuration using ovine lumbar vertebrae (1864N) was almost double that of the standard screw positioning (993N).
The clinical implication of this study is that top screw pullout resistance can be maximised by placing the top screw as close as possible to the top endplate and the bottom screw as close as possible to the bottom endplate, although this will have detrimental effects on the pullout of the second screw should the top screw pull out. Screw angulation is a less important factor but any angulation should be in a cephalad direction and around 10º in magnitude. The experimental results also suggest that the use of a staple may play a role in preventing cephalo-caudad pre-compression forces from reducing screw resistance to subsequent pullout forces.
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Estudo do Fluorelastômero Viton utilizado para revestimento da ponteira dos equipamentos endoscópicos. / Study of the Viton Fluorelastomer used for tip coating of endoscopic equipment.LIMA, Vanessa Sena Correia. 10 April 2018 (has links)
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Previous issue date: 2014-09-15 / Biomaterial é um termo usado para indicar os materiais que constituem as peças de
implantes médicos, dispositivos extracorporais, e descartáveis que têm sido
utilizados em medicina bem como em todos os aspectos de saúde do paciente. As
aplicações dos biomateriais são muitas e variadas, incluindo desde dispositivos de
uso prolongado, como veias e válvulas artificiais, a dispositivos de exames, como
endoscópios. Endoscopia, que significa olhar por dentro, trata-se de uma
especialidade médica que se utiliza de um equipamento chamado de endoscópio
para diagnóstico e tratamento de enfermidades. Através da endoscopia podem-se
diagnosticar enfermidades, efetuar biópsias de lesões, extrair corpos estranhos,
realizar dilatações, fazer acompanhamentos após cirurgias, passar sondas ou
cateteres, tratar sangramentos, retirar pólipos e acessar a via biliar para realizar
procedimentos cirúrgicos. Os endoscópios flexíveis possuem em sua ponta flexível
uma borracha conhecida como Fluoroelastômero Viton®. Os fluorelastômeros são
elastômeros sintéticos fluorados, conhecidos como Borracha Fluorada para serviços
em temperaturas elevadas e ambientes quimicamente agressivos. Baseado no
exposto este trabalho teve como objetivo estudar o fluorelastômero Viton® utilizado
no revestimento de ponteiras dos equipamentos endoscópicos. Foram verificadas
três grupos de amostras de ponteiras de endoscópios constituídas de Viton®
denominadas G, M e P, em sua forma virgem e tratadas com álcool etílico e HCl,
ambos concentrados, onde estas amostras foram caracterizadas por Microscopia
Óptica (MO), Microscopia Eletrônica de Varredura (MEV), Espectroscopia na Região
de Infravermelho com Transformada de Fourier (FTIR), Espectroscopia por Energia
Dispersiva de raios X (EDS), Difração de raios X (DRX), Ensaio de Ângulo de
Molhabilidade e Ensaio de Citotoxicidade. Verificou-se para todas as amostras (G, M
e P) uma superfície com morfologia granulada e irregular, com presença de
elementos contaminantes e imperfeições, com bandas características de
fluorelastômeros, difratogramas amorfos típicos de elastômeros, caráter hidrofílico e
toxicidade em meio celular exceto para a amostra M. Observou-se que o tratamento
com álcool etílico não provocou alteração estrutural no fluorelastômero agindo
apenas como eliminador de impurezas superficiais. O tratamento com HCl provocou
alterações na morfologia e estrutura química do elastômero. Verificou-se a
necessidade de adaptação da rota de produção deste fluorelastômero para
utilização como biomaterial. Foi proposta a utilização de revestimentos a base
siloxanos que possam aumentar a vida útil do fluorelastômero Viton®. / Biomaterial is a term used to indicate the materials constituting the parts of medical
implants, extracorporeal devices, disposable and which have been used in medicine
as well as in all aspects of patients' health. The applications of biomaterials are many
and varied, ranging from extended use devices such as artificial valves and veins,
the devices exams such as endoscopes. Endoscopy, which means looking inside, it
is a medical specialty that uses a device called endoscope for diagnosis and
treatment of diseases. By endoscopy can be diagnosed illnesses, perform biopsies of
lesions, extracting foreign bodies, perform dilations, do follow ups after surgery,
spend probes or catheters, to treat bleeding, remove polyps and access to the
surgical procedures biliary. Flexible endoscopes have in your flexible rubber tip one
known as Viton® fluoroelastomer. The fluoroelastomers are synthetic fluorinated
elastomers, known as Rubber Fluorinated services to high temperatures and
chemically aggressive environments. Based on the above this work was to study the
Viton® fluoroelastomer coating used on tips of endoscopic equipment. Three groups
of samples from the tips of endoscopes consist of Viton® called L, M and P, in its
virgin form and treated with HCl and ethyl alcohol, both concentrated where these
samples were characterized by Optical Microscopy (OM), Electron Microscopy Were
Verified (SEM), Spectroscopy in the Region of Fourier Transform Infrared (FTIR)
Spectroscopy Energy Dispersive X-ray (EDS), diffraction (XRD), test of Angle
Wettability and Cytotoxicity Assay rays. It was found for all samples (L, M, P) and a
surface irregular with granular morphology, presence of contaminants and
imperfections, characteristic bands of fluoroelastomers, typical XRD of amorphous
elastomers, hydrophilic, and toxicity in cell except for M. In the sample was observed
that treatment with ethanol did not cause structural changes in the fluoroelastomer as
scavenger only surface impurities. Treatment with HCl caused changes in the
morphology and chemical structure of the elastomer. There was a need to adapt the
production of fluoroelastomer route for use as a biomaterial. The use of coatings
siloxanes base that can increase the life of Viton® fluoroelastomer was proposed.
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Specifika ošetřovatelské péče u dětí podstupující endoskopické vyšetření trávicího traktu / Specifice of nursing care for children undergoing endoscopic examination of the gastrointestinal tractHALÁMKOVÁ, Hana January 2011 (has links)
Although it is not a new method endoscopy has undergone incredible development in recent years. The examination is however very unpleasant for a patient, which is why health care staff should be well trained, particularly for child patients. The aim of the thesis was to map the specifics of nursing care for children undergoing endoscopic examination of the gastrointestinal tract. We approached the whole issue from the point of view of caring staff ? nurses. In the theoretical part we first described the gastrointestinal tract anatomy, endoscopy development and types of endoscopic examination. Then we dealt with the role of a nurse in the care for child patients undergoing these examinations. We formed three goals for the research. Goal 1: To find out how nurses prepare child patients for the individual endoscopic examinations. Goal 2: To verify whether nurses caring about a child patient undergoing gastrointestinal tract endoscopy are specifically trained. Goal 3 served as the output of the work: To elaborate recommendation for nurses preparing child patients for the individual endoscopic examinations. We chose quantitative research for collection of the necessary information. A questionnaire designed for nurses caring for child patients was the data collection technique. The questionnaire was anonymous, distributed at paediatric clinics of faculty hospitals of Moravian region. 104 questionnaires suitable for processing returned from 140 issued. The research has shown that nurses working at the clinics where the research was performed master the correct nursing care for child patients undergoing endoscopic examination of the gastrointestinal tract. Nevertheless the fact that most information is gained upon practical experience, with low emphasis on initial and repeated training of nurses also results from the research. A recommendation was elaborated upon the gathered information in the form of a standard nursing procedure proposal.
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Medical use of radiation in gastroenterology:optimising patient radiation exposure during endoscopic retrograde cholangiopancreatography (ERCP)Saukko, E. (Ekaterina) 04 December 2018 (has links)
Abstract
Fluoroscopically guided procedures are currently an area of special concern in relation to radiation protection, as they may produce a high radiation dose to patients and increase the risk of skin injury. ERCP is a gastrointestinal procedure used as a gold standard in the treatment of pancreatobiliary disorders. It is performed under endoscopic and fluoroscopic guidance. Recently, both the number and the complexity with associated increased technical difficulty of therapeutic ERCP procedures have significantly increased.
The present study aimed to assess the medical use of radiation in ERCP, with special emphasis on optimisation of radiation protection of patients. For this purpose, the level of patient radiation exposure during ERCP was evaluated by registering the radiation dose indices in Finnish hospitals. The entrance surface dose was measured by thermoluminescent dosimeters and the effective dose was estimated using conversion coefficients. For dose optimisation and for quality assurance, the local diagnostic reference levels (DRL) for ERCP were established and reviewed after five years. A single centre prospective analysis was conducted to identify patient-, procedure- and operator-related factors affecting dose area product (DAP) and fluoroscopy time (FT).
The results showed a large variation of dose indices in overall, as among participating hospitals due to differences in patient characteristics, operator, equipment and procedural complexity. The risk of radiation-induced skin injury and the lifetime cancer risk seems to be reasonably low, indicating ERCP to be a low-dose study. Local DRL is an effective tool in the optimisation process, as a certain degree of dose reduction was achieved during the years. Multiple factors were found to affect DAP and FT in ERCP. The awareness of these factors may help to predict possible prolonged procedures that cause a higher radiation dose to the patient and thus facilitate the use of appropriate precautions. / Tiivistelmä
Säteilysuojelun näkökulmasta läpivalaisuohjauksessa tehtävät toimenpiteet ovat erityisen huolen aiheena, koska ne voivat aiheuttaa potilaille suuria säteilyannoksia ja siten lisätä ihovaurion riskiä. ERCP on ruoansulatuskanavan endoskopiatoimenpide, jota käytetään haima- ja sappitiesairauksien hoidossa kultaisena standardina. ERCP suoritetaan duodenoskoopilla läpivalaisukontrollissa. Viime vuosina ERCP toimenpiteiden määrät ja toimenpiteiden monimutkaisuus ovat kasvaneet merkittävästi lisääntyneen teknisen haastavuuden vuoksi.
Tutkimuksen tarkoituksena oli arvioida säteilyn lääketieteellistä käyttöä ERCP:ssa, kiinnittäen eritystä huomiota potilaan säteilysuojelun optimointiin. Potilaan säteilyaltistuksen tasoa ERCP:ssa arvioitiin keräämällä potilasannoksia suomalaisista sairaaloista, pinta-annokset mitattiin termoloistedosimetreilla ja efektiivinen annos laskettiin muuntokertoimilla. Säteilyaltistuksen optimointi- ja laadunvalvonnan työkaluksi ERCP:lle asetettiin paikalliset vertailutasot ja ne tarkistettiin 5 vuoden kuluttua. Potilaaseen, toimenpiteeseen ja toimenpiteen suorittajaan liittyvät tekijät, jotka vaikuttavat annoksen ja pinta-alan tuloon (DAP) sekä läpivalaisuaikaan, selvitettiin retrospektiivisesti yhdessä sairaalassa.
Tutkimuksen tulokset osoittivat, että potilaan säteilyannoksissa oli suurta vaihtelua niin yleisesti, kuin osallistuvien sairaaloiden välillä. Vaihtelu johtui potilaan ominaisuuksista, erilaisista läpivalaisulaitteista, toimenpiteen suorittajista ja ERCP toimenpiteiden vaikeusasteesta. Säteilyn aiheuttaman ihovaurion riski ja elinikäinen syöpäriski näyttäisi tulosten perusteella olevan kohtuullisen alhainen, mikä osoittaa, että ERCP on matala-annostutkimus. Paikallinen vertailutaso osoittautui tehokkaaksi optimointityökaluksi, sillä annostason lasku ERCP:ssa saavutettiin vuosien kuluessa. Useiden tekijöiden todettiin vaikuttavan DAP:n ja läpivalaisuaikaan ERCP:ssa. Näiden tekijöiden tiedostaminen voi auttaa tunnistamaan etukäteen ne haastavat ERCP toimenpiteet, jotka voivat aiheuttaa suuria säteilyannoksia potilaille, ja siten mahdollistaa niihin varautumisen.
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Preservação de cadáver de coelho (Oryctolagus cuniculus) com a solução de Larssen modificada para treinamento em cirurgia videolaparoscópicaMenezes, Cláudio Leonardo Montassieur de January 2012 (has links)
As habilidades psicomotoras são fundamentais para conduzir de forma adequada e segura um procedimento videocirúrgico. A cirurgia laparoscópica difere da cirurgia tradicional, pois o cirurgião deve guiar suas manobras em um ambiente tri-dimensional, através de imagem bi-dimensional, é privado da sensação táctil direta com os tecidos e necessita adquirir coordenação motora para a utilização de um novo tipo de instrumental cirúrgico. Faz-se necessário o desenvolvimento de modelos de treinamento factíveis para a formação de cirurgiões laparoscópicos, que simulem adequadamente as situações vivenciadas na sala de operação. Esta pesquisa objetivou desenvolver um modelo de cadáver de coelho embalsamado, utilizando a solução de Larssen modificada, para treinamento em quatro procedimentos laparoscópicos: colecistectomia, nefrectomia, esplenectomia e criptorquidectomia. Foram utilizados 17 coelhos de diferentes raças, submetidos a dois procedimentos cirúrgicos cada um. Destes, 15 foram eutanasiados, embalsamados e criopreservados. Após uma semana, os animais foram descongelados em caixa plástica com água aquecida a 40ºC e utilizados no treinamento de um cirurgião sem experiência prévia em videocirurgia. Dois coelhos foram operados vivos, sob anestesia geral inalatória, ao final da fase de treinamento, para verificar a capacidade do cirurgião em realizar as quatro técnicas laparoscópicas citadas, sem ocorrência de complicações significativas, sendo estes animais eutanasiados ao final dos procedimentos. Os cadáveres de coelhos mantiveram suas características teciduais semelhantes àquelas encontradas em um animal vivo. A coloração dos tecidos e órgãos abdominais foi bastante similar ao verificado in vivo, enquanto o odor variou entre leve e moderado e a textura variou entre normal e friável. A imersão dos cadáveres em água aquecida foi efetiva para alcançar o descongelamento completo, com mínima interferência da temperatura ambiente, tendo duração de quatro a cinco horas. O modelo experimental proposto neste estudo apresentou boas condições para execução e treinamento de colecistectomia laparoscópica, nefrectomia total laparoscópica e criptorquidectomia laparoscópica. As condições encontradas na cavidade abdominal dos coelhos embalsamados não foram satisfatórias para a prática adequada de esplenectomia laparoscópica, pela dificuldade em estabelecer boa visualização e manipulação do baço. / Psychomotor skills are essential to correctly and safely conduct endoscopic surgical procedures. Laparoscopic surgery differs from traditional surgery because the surgeon must guide his maneuvers in a tri-dimensional environment, through a bi-dimensional image, he’s deprived of direct tactile sensation with the tissues and needs to acquire motor coordination to use a new type of surgical instruments. Its necessary feasible experimental models to train laparoscopic surgeons, which properly simulates the situations experienced in the operation room. This research aims at proposing a embalmed rabbit cadaver model, prepared with the modified Larssen solution, for training in four laparoscopic procedures: cholecystectomy, nephrectomy, splenectomy, cryptorchidectomy. Seventeen rabbits from different breeds were used, each undergoing two surgical procedures. Of these, 15 were euthanized, embalmed and cryopreservated. After one week, they were thawed in a plastic box with water heated to 40ºC and used in the training of a surgeon with no previous experience with endoscopic surgery. Two rabbits underwent surgery under general anesthesia with a volatile agent, at the end of the training step, to check the surgeon’s ability to perform the four mentioned laparoscopic techniques, without the occurrence of major complications, both being euthanized at the end of the procedures. The rabbit cadavers kept tissues properties similar to those found in a living animal. The color of the abdominal tissues and organs was very close to that verified in vivo, although odor tended from slight to moderate and consistency tended from normal to friable. The cadavers immersion in heated water was effective to completely thaw then, with minimum interference of room temperature, within four to five hours. The experimental model proposed in this study presented valuable conditions to perform and train laparoscopic cholecystectomy, laparoscopic total nephrectomy and laparoscopic cryptorchidectomy. The state of the abdominal cavity found in the embalmed rabbits was unsatisfactory for suitable practice of laparoscopic splenectomy, because of the difficulty in establishing good visualization and manipulation of the spleen.
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