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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.
21

Left Shoulder Pain After Routine Colonoscopy: An Unusual Presentation of Splenic Laceration

Dziadkowiec, Karolina N., Stawinski, Peter M., Radadiya, Dhruvil, Katz, Aviv 21 April 2020 (has links)
Splenic injury is an uncommon complication following a colonoscopy procedure. Splenic laceration typically presents with post-procedural abdominal pain. We present a case of non-specific shoulder pain, following an uneventful routine colonoscopy and highlight the importance of maintaining a high degree of clinical suspicion for the general gastroenterologist.
22

Deformable Registration of Supine and Prone Colons for CT Colonography

Suh, Jung Wook 21 November 2007 (has links)
State-of-the-art three-dimensional endo-luminal virtual colonoscopy (VC) or CT colonography (CTC) is a minimally invasive medical procedure that examines the entire colon in order to detect polyps and colorectal cancer. Most colon cancers malignantly transform from polyps, which are extra growths on the surface of the mucous membrane. Three dimensional endoscopic colon lumen interior images offered by CTC allow physicians to examine the colon interactively. Thus, CTC has several advantages over conventional optical colonoscopy including reduced risk. One of the challenging problems that prevent practical use in clinical situations is the complexity of the human colon. The colon's deformation by peristalsis and the diverse shapes of polyps make it difficult to distinguish polyps from other non-threatening entities in the colon. Hence, most CTC protocols acquire both prone and supine images to improve the visualization of the lumen wall, reduce false positives, and improve sensitivity. Comparisons between the prone and supine images can be facilitated by computerized registration between the scans. In this dissertation, two algorithms for registering colons segmented from prone and supine images are presented. First is an algorithm for three dimensional registration of the prone and supine colon when both are well distended and there is a single connected lumen. Second is another registration algorithm between colons with topological differences caused by inadequate bowel preparation or peristalsis. Such topological changes make deformable registrations of the colons difficult, and at present there are no registration algorithms which can accommodate them. The first algorithm uses feature matching of the colon centerline and a modified version of the demons deformable registration algorithm to define a deformation field between the prone and supine lumen surface. The second method utilizes embedded map representation of colon volume. The two proposed colon registration methods will contribute to improving the accuracy of the computerized registration process and increasing the versatility of the clinical use of CT colonoscopy. / Ph. D.
23

Effective and Accelerated Informative Frame Filtering in Colonoscopy Videos Using Graphic Processing Units

Karri, Venkata Praveen 08 1900 (has links)
Colonoscopy is an endoscopic technique that allows a physician to inspect the mucosa of the human colon. Previous methods and software solutions to detect informative frames in a colonoscopy video (a process called informative frame filtering or IFF) have been hugely ineffective in (1) covering the proper definition of an informative frame in the broadest sense and (2) striking an optimal balance between accuracy and speed of classification in both real-time and non real-time medical procedures. In my thesis, I propose a more effective method and faster software solutions for IFF which is more effective due to the introduction of a heuristic algorithm (derived from experimental analysis of typical colon features) for classification. It contributed to a 5-10% boost in various performance metrics for IFF. The software modules are faster due to the incorporation of sophisticated parallel-processing oriented coding techniques on modern microprocessors. Two IFF modules were created, one for post-procedure and the other for real-time. Code optimizations through NVIDIA CUDA for GPU processing and/or CPU multi-threading concepts embedded in two significant microprocessor design philosophies (multi-core design and many-core design) resulted a 5-fold acceleration for the post-procedure module and a 40-fold acceleration for the real-time module. Some innovative software modules, which are still in testing phase, have been recently created to exploit the power of multiple GPUs together.
24

Development and Testing of the Colonoscopy Embarrassment Scale

Mitchell, Kimberly Ann 26 January 2010 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Colorectal cancer (CRC), the third leading cause of cancer-related death in the U.S., could largely be prevented if more people had polyps removed via colonoscopies. Embarrassment has been identified as one important barrier to colonoscopy, but little is known about embarrassment in this context. Further, there is no instrument available to measure this construct. Therefore, the purpose of this study was to develop a reliable and valid instrument to measure colonoscopy-related embarrassment. The study aims were to: 1) estimate reliability and validity of a new instrument, the Colonoscopy Embarrassment Scale (CES); 2) examine relationships among demographic/personal characteristics, health beliefs, and CES scores; 3) examine relationships among demographic/personal characteristics, physician recommendation, health beliefs, and colonoscopy compliance; and 4) evaluate participants’ perceptions of aspects of having a colonoscopy that are most embarrassing and their suggestions for reducing embarrassment. The Health Belief Model and Transtheoretical Model of Change provided theoretical support for this study. Participants were HMO members aged 50-65 years (n=234). Using a cross-sectional, descriptive research design, data were collected using a mailed survey. The response rate was 56%. Data were analyzed using independent samples t-tests, correlations, Chi Square, and regression. Results showed that the six-item CES had internal consistency (Cronbach’s alpha of .89) and construct validity. Lower income, higher BMI, lower CRC knowledge, higher barriers, and lower self-efficacy were related to higher CES scores (or more embarrassment). Higher CRC knowledge, lower barriers, higher self-efficacy, and a physician recommendation for the test were related to higher compliance with colonoscopy. Lower barriers, higher self-efficacy, and a physician recommendation were predictive of compliance with colonoscopy. In conclusion, embarrassment is a significant barrier to colonoscopy, yet there are steps that can be taken to reduce embarrassment such as increasing privacy and limiting bodily exposure. The CES is a tool that can be used to measure colonoscopy-related embarrassment and the results could be used in developing further interventions to reduce embarrassment, leading to increased colonoscopies and lower mortality.
25

Evaluation of an Active Colonoscopy Training Model

Kale, Ravindra V. January 2012 (has links)
No description available.
26

Effects of dehydration time and staining technique on microscopic diagnosis of colitis

Liljeroth, Annica January 2008 (has links)
<p>ABSTRACT</p><p>In the western world colitis is a common chronic disease and in Sweden the prevalence is around 1%. If a patient has bloody diarrhea it is probably ulcerative proctocolitis or Crohn’s disease, whereas if the diarrhea is watery, it is microscopic colitis. For a diagnosis, the patient has to do a colonoscopy and a colonic biopsy sample has to be taken. The biopsy sample will be sent to a laboratory for sectioning, staining and microscopic analysis.</p><p>In this study we compared the effects of short and long dehydration time of the sample before the sectioning. We also compared staining with Alcianblue/Van Gieson and Van Gieson alone.</p><p>Our results showed that a short dehydration time was a milder treatment and made it easier to section the biopsy sample. The comparison of the two methods was unsuccessful because the staining with Alcianblue/Van Gieson failed.</p>
27

A colonoscopia com e sem auxílio de métodos de cromoscopia no diagnóstico das lesões planas, deprimidas e elevadas do cólon e reto / Colonoscopy making or not use of chromoscopy methods on the diagnosis of flat, depressed and augmented colorectal lesions

Tafner, Edmar 16 March 2011 (has links)
O câncer colorretal (CCR) é uma das maiores causas de óbito no mundo industrializado, com uma incidência anual de 800.000 casos novos, o que significa 8,5% de todos os novos e 12% das mortes relacionadas a essa doença. No Brasil, excluindo-se os cânceres de pele não melanoma, o CCR é o quarto mais freqüente entre os homens e o terceiro entre as mulheres. O risco de desenvolver CCR é de aproximadamente 5% a 6% na população ocidental. Existem evidências epidemiológicas de redução do CCR em 60% -90% quando a colonoscopia com polipectomia é usada preventivamente A colonoscopia ainda é o melhor método para o diagnóstico precoce do CCR e das lesões precursoras. Contudo existem falhas de detecção não desprezíveis. O objetivo deste estudo foi comparar o resultado do exame detalhado da mucosa do cólon e do reto através da colonoscopia convencional, da cromoendoscopia e do NBI, na detecção de lesões elevadas, deprimidas e planas em pacientes submetidos ao exame sem antecedentes pessoais e ou familiares. Entre janeiro de 2007 e outubro de 2009 foram selecionados 181 pacientes divididos aleatoriamente em três grupos: A: 48 pacientes, controle; B: 29 pacientes, NBI; C: 104 pacientes, cromoscopia difusa. Pode-se observar que dos 181 pacientes examinados 38 (21%) não apresentavam lesões. Os 143 pacientes com lesão, apresentaram um número médio de 2,65 lesões, com mínimo de 1 e máximo de 7 lesões. Nos total dos 181 pacientes e no conjunto dos 143 pacientes com lesões não foi observada diferença estatisticamente significante entre os três grupos A, B e C para a idade, o tempo reto-ceco e o tempo ceco-reto, enquanto que para a altura, peso e conseqüente IMC houve variação estatística. O tamanho médio das 379 lesões encontradas nos 143 pacientes, avaliado pelo seu diâmetro foi de 5,45 ± 2,84 mm, sem variação estatística entre os grupos, entre os hemicólons e entre os hemicólons nos grupos. Os tamanhos das lesões foram reunidos em três intervalos distintos: até 5 mm (76,30%), de 6 a 10 mm (19,50%) e de 11 a 20 mm (4,20%). Do total de 379 lesões, 203 (53,6%) mostraram-se neoplásicas e 176 (46,4%) não neoplásicas. O tamanho médio das 203 lesões neoplásicas foi de 5,96 mm, e das 176 não neoplásicas, 4,87 mm. As lesões neoplásicas mostraram-se maiores que as não neoplásicas, com significância estatística. Nos grupos não houve variação significante entre neoplasia e não neoplasia, mas diferença significante entre o tamanho das neoplasias e não neoplasias. Não houve diferença estatística entre os tamanhos das lesões nos dois hemicólons, mas com diferença significante entre os tamanhos das lesões neoplásicas e não neoplásicas. O mesmo se observa quando os segmentos do cólon são analisados individualmente. Os dois segmentos que apresentaram diferença significante, especificamente, quanto ao tamanho das lesões neoplásicas e não neoplásicos foram o sigmóide e o transverso. Nota-se que todas as lesões subpediculadas e as lesões plano-elevadas com depressão central eram neoplásicas. As lesões planas e neoplásicas são proporcionalmente mais visíveis no hemicólon direito nos grupos B (85,7%) e C (67,9%), sem diferença estatística. As hipóteses diagnósticas das lesões feitas durante o exame colonoscópico foram comparadas com os resultados histopatológicos. Pode-se observar que no grupo A sensibilidade de 82,7%, especificidade de 59%, com taxa de concordância de 72,5 %, considerada regular, no grupo B sensibilidade de 92,3%, especificidade de 61,9%, com concordância de 78,7 %, regular e no C sensibilidade de 88,8%, especificidade de 79,3%, taxa de concordância de 84,2%, considerada boa. Proporcionalmente o grupo C tem maior número de pacientes com três ou mais lesões e três ou mais lesões neoplásicas, mas sem valor estatístico. Conclui-se que não houve diferença estatística entre os 181 pacientes examinados e os 143 pacientes com lesões, quanto aos dados gerais, não houve diferenças significativas quanto ao número relativo, ao tipo e ao tamanho das lesões. As lesões neoplásicas apresentam-se maiores quando comparadas às não-neoplásicas, com significância estatística. A concordância entre a hipótese diagnóstica colonoscópica e a histologia é maior no grupo da cromoscopia / Colorectal cancer (CRC) is one of the largest causes of death on the industrialized world. Its annual incidence of 800.000 new cases means 8,5% of all the new ones and 12% of deaths related to this disease. In Brazil, excluding the non-melanoma skin-cancers, CRC is the fourth more frequent among men and the third one among women. The risk for developping CRC is approximately of 5 to 6% on the Western population. There are epidemiological evidences for reducing CRC on 60-90% when colonoscopy with polypectomy is used preventively. Colonoscopy is still the best method both for the early dyagnosis of CRC and precursor lesions. However, there are non-contemptible failures on the detection. This paper purpose was comparing the result of colon and rectum mucous membrane detailed test through conventional colonoscopy, chromoendoscopy and NBI, on the detection of augmented, depressed and flat lesions in patients submitted to it without any personal or familiar antecedents. Between January 2007 and October 2009 181 patients were selected randomically and divided into 3 groups: A: 48 control patients; B: 29 patients, NBI; C: 104 patients, diffuse chromoscopy. It is observed that, from the 181 examined patients, 38 (21%) didnt present lesions. The 143 patients with lesion, presented an average number of 2,65 lesions, with a minimum of 1 and a maximum of 7 lesions. On the total of the 181 patients and on the whole of the 143 patients with lesions it was not observed any statistically significant difference among the three groups A, B and C as for Age, the Rectum-Cecum Time and the Cecum-Rectum Time, while there was a statistical variation for Height, Weight and consequent bmi. The average size of the 379 lesions found on the 143 patients, assessed by its diameter was of 5,45 mm (2.14 in.) + 2,84 mm (1,11 in), without any statistical variation among the groups, among the hemicolons and among the hemicolons in the groups. The size of the lesions were gathered into three distinct intervals: up to 5 mm [1.9 in.] (76,30%), from 6 mm [2.3 in.] to 10 mm [3.9 in] (19,50%) and from 11 to 20 mm [4.3 to 7.8 in] (4,20%). From the total of 379 lesions, 203 (53,6%) revealed themselves neoplastic and 176 (46,4%) non-neoplastic. The average size of the 203 neoplastic lesions was of 5,96 mm (2.34 in.), and of the 176 non-neoplastic ones, 4,87 mm [12,36 in]. Neoplastic lesions have shown larger than the non-neoplastic ones, with a stastistical significance. On the groups there is any significant variation between neoplasia and non-neoplasia, but a significant difference between the neoplasias and non-neoplasias size. There was any statistical difference among the lesion size on both hemicolons, however, a significant difference among the sizes of neoplastic and non-neoplastic ones. The same is observed when colon segments were analyzed individually. The two segments that have presented significant lesions, specifically on what concerns the size of neoplastic and non-neoplastic ones were the Sigmoid and the Transverse. It is observed that all the subpediculated lesions and the flat-augmented ones with a central depression were neoplastics. The flat and neoplastic lesions are proportionally more visible on the right hemicolon at groups B (85,7%) and C (67,9%), without any statistical difference. The diagnostic hypotheses of the lesions grown during the colonoscopic test were compared to the histopathological results. On control group (A) it is observed a 82,7% sensibility, a 59% specificity with a concordance rate of 72,5%, considered regular. On group B it is observed a 92,3% sensibility, a 61,9% specificity, with a regular concordance rate of 78,7%. On group C it is observed a 88,8% sensibility, a 79,3% specificity, a 84,2% concordance rate, considered good. Proportionally group C has a larger number of patients with 3 or more lesions and or more neoplastic lesions, but with no statistical value. On what concerns general data, it is concluded that there wasnt any statistical difference among the 181 patients examined and the 143 ones presenting lesions as for the relative number, the type and size of the lesions. Neoplastic lesions appear to be larger when compared to non-neoplastic ones, with a statistical significance. The concordance between the colonoscopic diagnostic hypothesis and the histology is larger on chromoscopy group
28

Preparo de cólon para realização de colonoscopia: estudo prospectivo randomizado comparativo entre solução de polietilenoglicol baixo volume mais bisacodil versus solução de manitol mais bisacodil / Bowel preparation for performing colonoscopy: prospective randomized comparison study between low volume solution of polyethylene glycol plus bisacodyl versus bisacodyl and mannitol solution

Vieira Junior, Manoel Carlos 31 August 2011 (has links)
A colonoscopia é atualmente o padrão ouro para investigação da mucosa dos cólons, reto e íleo terminal. Para sua realização, há necessidade de uso de soluções para limpeza do cólon que, em geral, são mal toleradas pelos pacientes. Os objetivos do presente estudo foram comparar duas soluções de preparo intestinal para colonoscopia, quanto à efetividade, tolerabilidade, aceitabilidade e segurança em pacientes que se submeteriam a colonoscopia eletivamente, no Centro de Diagnóstico em Gastroenterologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Trata-se de estudo unicêntrico, prospectivo, com alocação aleatória dos pacientes. Cem pacientes pareados por sexo e idade foram randomizados em dois grupos. O grupo I recebeu bisacodil mais 1 litro de Polietilenoglicol (PEG) na véspera e 1 litro no dia do exame. O grupo II recebeu bisacodil na véspera e 1 litro de manitol 10% no dia do exame. A mesma dieta foi orientada nos dois grupos. A qualidade do preparo foi graduada através das escalas de Boston e Ottawa. A tolerabilidade e aceitabilidade foram aferidas por questionários previamente estudados. Quanto à segurança, foram ava liadas: variação de sinais vitais antes e após o preparo e complicações. Noventa e seis pacientes (96%) completaram o estudo. Não se observou diferença na qualidade do preparo entre os grupos(p = 0,059). Quanto à tolerabilidade, o grupo I (PEG) apresentou frequência significativamente menor de náusea, vômito, dor abdominal e distensão abdominal (p < 0,05). A aceitabilidade foi significativamente melhor com o grupo I (PEG) (p < 0,05). Em relação à segurança, o grupo I (PEG) apresentou-se mais seguro. No presente estudo, podemos concluir que ambos os preparos são semelhantes em eficácia (p > 0,05) e a solução de PEG apresentou melhor tolerabilidade, aceitabilidade e segurança em comparação ao preparo com manitol (p < 0,05). / Colonoscopy is currently the gold standard to examine the colon, the rectum, and the terminal ileum. To perform a colonoscopy, is necessary to use solutions to clean the colon that are generally poorly tolerated by the patients. The study aims to compare the effectiveness, tolerability, acceptability and safety of two solutions used for intestinal preparation for elective colonoscopy examination in the Diagnosis Center Of Hospital das Clinicas, Faculty of Medicine, University of São Paulo. It is a Prospective study carried out in a single center, with random allocation of the patients. One hundred patients that were paired based on sex and age were randomized into two groups. Group I received bisacodyl plus 1 liter of polyethylene glycol (PEG) the night before and 1 liter on the day of the exam. Group II received bisacodyl the night before and 1 liter of a 10% mannitol solution on the day of the exam. The patients diet was the same for both groups. The quality of the preparation was graded based on the Boston and Ottawa scales. Tolerability and acceptability were measured using previously validated questionnaires. In terms of safety, variations in vital signs before and after the preparation were recorded, as well as any complications. Ninety-six patients (96%) completed the study. No difference was observed in the quality of the preparation between the two preparation methods (p = 0,059). As for tolerability, group II (the mannitol preparation group) presented a significantly higher frequency of nausea, vomiting, abdominal pain and abdominal distension (p < 0,05). Acceptability was significantly better in group I (p < 0,05). The PEG solution was also shown to be safer than mannitol. Based on the present study, the following conclusions can be made: 1) Both methods of preparation had similar efficiencies (p > 0,05); 2) PEG method showed higher tolerability, acceptability and safety compared to the mannitol method (p < 0,05).
29

Lessons learnt from quality improvement in radiological service : Four key factors for sucess

Löfgren, Oskar, Österström, Anna January 2012 (has links)
BackgroundIn this study, we describe a Quality Improvement (QI) intervention in three radiology departments within the Swedish health care system, with a special focus on access and methodology. AimThe goals for the QI-intervention were to implement best practice for patients with suspected colon cancer, and reduce the Turn Around Time (TAT).The aim of the study was to identify relevant factors for successful QI in order to further develop the organisation to create a system of continuous QI (CQI) for the radiological service. MethodsInitially, a multiprofessional QI-team was formed. To identify waste and areas for improvement, process mapping and lead time analysis were conducted during a collaborative learning approach. A focus group interview was carried out with the participants in the QI-intervention and the local managers, and a qualitative content analysis of the focus group transcript was performed. ResultsBest practise was gradually introduced, and overall access was improved, but TAT was not changed. Four key factors for CQI were revealed; Communication, Engagement, Context, and Patient- and Customer focus. Moreover, the impact of providing useful and reliable measurements to the frontline staff was found to be high DiscussionThe lack of decreased TAT indicates that further redesign of the radiology process is needed. As the impact of measurements was considered high, an improved system for obtaining and providing useful information to all parts in the organization is essential. Moreover, the infrastructure for CQI needs to be developed further, e.g. by clarifying roles, educating in improvement knowledge, and developing multiprofessional meetings. Finally, motivating and engaging staff is crucial to improve healthcare. It is important with a deeper understanding what triggers this, patient centeredness could be one.
30

Impact of a Multifaceted Intervention on Promoting Adherence to Screening Colonoscopy among HIV/AIDS Population

Ferron, Pansy 21 December 2011 (has links)
Colorectal cancer (CRC) is the second leading cause of death in the United States and has the highest death rate among Blacks. Whereas studies have targeted patients to increase CRC adherence in the general population few studies have focused on improving providers’ adherence to screening guidelines. Also, CRC screening studies among HIV-positive patients consistently show lower screening rates compared to screening rates among HIV negative persons. Results of screening colonoscopy studies among HIV positive patients show higher prevalence of neoplastic lesions and colon cancer is diagnosed at advanced cancer stages; these patients have shorter disease-free survival compared to HIV-negative patients. The aim of this transdisciplinary retrospective–prospective and randomized control study is to examine providers’ adherence to screening colonoscopy guidelines before and after screening reminders, evaluate the impact of an educational screening video and review of colonoscopy decisions tree plus usual care on patient adherence compared to usual care only. Results showed that providers’ adherence to screening colonoscopy guidelines significantly increased after reminders to refer patients were placed in medical records. The randomized trial showed that patients in the intervention group were more adherent to screening colonoscopy appointments compared to patients in the usual care arm. Also, patients with little or no social support in the intervention arm were more likely to keep appointments. This is the first reported study of a Transdisciplinary prevention model integrating evidence-based medicine, behavioral medicine and human factors decision support through a multi-faceted intervention to increase screening colonoscopy adherence in the HIV population. We integrated a provider reminder system, patient informed decision support of colonoscopy educational video and decision tree review in addition to patient provider communication to promote increased provider and patient screening behavior. Further studies are needed to elucidate the impact of patient centered intervention strategies and social support on screening colonoscopy behavior.

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