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Dissertations / Theses on the topic 'Endoscopic surgery'
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1
Tan, Hock Lim. "The development of paediatric endoscopic surgery /." Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09MD/09mdt161.pdf.
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Fan, King-man Joe, and 樊敬文. "Natural orifice translumenal endoscopic surgery (NOTES)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45872004.
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Tighe, Jonathan L'Estrange. "Industrial design in endoscopy : the development of a tissue and organ extractor." Thesis, Queensland University of Technology, 1997. https://eprints.qut.edu.au/36028/7/36028_Digitised_Thesis.pdf.
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Throughout history, developments in medicine have aimed to improve patient
quality of life, and reduce the trauma associated with surgical treatment.
Surgical access to internal organs and bodily structures has been traditionally
via large incisions. Endoscopic surgery presents a technique for surgical
access via small (1 Omm) incisions by utilising a scope and camera for
visualisation of the operative site. Endoscopy presents enormous benefits for
patients in terms of lower post operative discomfort, and reduced recovery
and hospitalisation time.
Since the first gall bladder extraction operation was performed in France in
1987, endoscopic surgery has been embraced by the international medical
community. With the adoption of the new technique, new problems never
previously encountered in open surgery, were revealed. One such problem is
that the removal of large tissue specimens and organs is restricted by the
small incision size. Instruments have been developed to address this problem
however none of the devices provide a totally satisfactory solution. They have
a number of critical weaknesses:
-The size of the access incision has to be enlarged, thereby
compromising the entire endoscopic approach to surgery.
- The physical quality of the specimen extracted is very poor and is not
suitable to conduct the necessary post operative pathological
examinations.
-The safety of both the patient and the physician is jeopardised.
The problem of tissue and organ extraction at endoscopy is investigated and
addressed. In addition to background information covering endoscopic
surgery, this thesis describes the entire approach to the design problem, and
the steps taken before arriving at the final solution.
This thesis contributes to the body of knowledge associated with the
development of endoscopic surgical instruments. A new product capable of
extracting large tissue specimens and organs in endoscopy is the final
outcome of the research.
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Chun, Mei-yee Elke. "Comparing Hong Kong market experience with the market development in China in minimally invasive surgery /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19876671.
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Mouton, Wolfgang Georg. "Effects of humidified gas insufflation in endoscopic surgery /." Title page, contents and abstract only, 1998. http://web4.library.adelaide.edu.au/theses/09MS/09ms934.pdf.
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Diale, Ndivhuwo. "Audit of outcomes of endoscopic cholesteatoma ear surgery." Master's thesis, Faculty of Health Sciences, 2019. http://hdl.handle.net/11427/31190.
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Background: Endoscopic ear surgery has gained acceptance as a complementary tool to microscopic ear surgery, but perhaps not so much as an instrument for exclusive use.With this approach becoming popular, there is scarce data on cholesteatoma recidivism and hearing outcomes, when exclusively used. Objectives: Auditing outcomes of endoscopic ear surgery for the surgical management of cholesteatoma in the Groote Schuur hospital (above13 year age group) and the Red Cross War Memorial Children’s hospital (below 13 year age group) , with a secondary aim of comparing recidivism and hearing outcomes of 4 different surgical techniques for cholesteatoma resection, namely, exclusive endoscopic (EES), microscopic canal wall down (CWD), microscopic canal wall up (CWU) and combined endoscopic-microscopic techniques. Methods: A retrospective chart review was conducted at our two tertiary academic referral hospitals in Cape Town, namely, Red Cross War Memorial Children’s Hospital and Groote Schuur Hospital from January 2012 to December 2016. Results: A total of 128 cholesteatoma ear surgeries were done; 110 patients were above the age of 13 years and 18 patients were below the age of 13 years. Eight Red Cross patients underwent EES, 7 had CWU, 2 had CWD and 1 had a combined technique. Overall recidivism rate in this population was 33% (6/18), of which 2 were approached exclusively endoscopically, 2 underwent a microscopic CWU, 1 had a CWD and 1 had combined endoscopic-microscopic approach. The mean postoperative hearing in this group was 40dB compared to a preoperative mean of 50,3 decibels (dB). In the Groote Schuur group, 23 underwent an exclusive endoscopic approach; 42 had a CWU, 40 had a CWD and 5 had a combined endoscopic-microscopic approach. Overall recidivism rate for the above 13 year old group was 17% (19/110). Of those, 7 were from the endoscopic group, 8 from the CWU group, 1 from CWD group and 3 from the combined technique group. Mean postoperative hearing was 47,4dB compared to a preoperative hearing of 48,4dB. Conclusions: The CWD technique demonstrated superior outcomes in both the above and below 13 year age groups. In the above 13 year old group, the EES approach had the same recurrence rate as CWU. While paediatric cholesteatomas have much higher recidivism rates compared to adults, our below 13 year old group was too small to conclude any statistical significant differences between the different approaches, and therefore, further studies are required in this age group. Management of cholesteatoma requires a highly individualized approach that takes into account anatomic, clinical and social factors to determine the most appropriate surgical treatment paradigm
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Poon, Tung-chung Jensen, and 潘冬松. "Laparoscopic colorectal resection: the impacton clinical outcomes & strategies to further optimize its results." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45205711.
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Schomisch, Steve J. "Overcoming Barriers to Natural Orifice Translumenal Endoscopic Surgery (NOTES)." Cleveland State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=csu1251915281.
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Lau, Hung, and 劉雄. "Endoscopic totally extraperitoneal inguinal hernioplasty: techniquesand advances for optimal outcome." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36425242.
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Erian, Mark. "Contributions to the practice of endoscopic surgery in gynaecology : based on personal published work 1990-2005 /." [St. Lucia, Qld.], 2006. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19784.pdf.
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Surangsrirat, Decho. "Computer Integrated Endoscopic Simulator for Training in Esophagogastroduodenoscopy." Scholarly Repository, 2001. http://scholarlyrepository.miami.edu/oa_dissertations/545.
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We propose a computer integrated endoscopic simulator for training in upper endoscopy as a low-cost alternative to the traditional training methods and virtual reality simulators. The use of a real endoscope in conjunction with our simulator and computer system in an actual operating room setup makes the training environment similar to a real procedure. Endoscopic surgery is the performance of surgery through a small incision with the aid of special medical equipment called a flexible endoscope. The advantage of this technique over open surgery is that there is significantly less operative trauma, resulting in less pain and a shorter recovery time. Side effects of the surgery, such as the risk of infection, are also reduced. While endoscopy procedure has tremendous benefits, surgeons require considerable practice and time to develop competency. Traditionally, the procedure has been taught at the expense of patient comfort and safety, in other words, gastroenterology training fellows have performed the surgery under the supervision of physicians. Patients who undergo the endoscopies performed by fellows, particularly early in the training period, have been more likely to suffer more discomfort and prolonged procedures. In this study, we introduce a new type of simulator which combines the use of mechanical model and computer system as an additional or low-cost alternative for training in upper endoscopy. Our approach is to integrate a computer system with a realistic mechanical model to create a computer-based simulator for upper endoscopy training. The simulator will cover the basics of flexible endoscopy and teach a trainee the skills required to perform upper endoscopy. The mechanical training model with a sensor system that simulates a human upper gastrointestinal tract, including pathologies such as ulcers and polyps, will be built and integrated with computer software. The software offers the following functions: provides help to the trainee, provides curriculum-required learning tasks, and assesses the performance and diagnostic skills. Due to the optical nature of an endoscopic lens, the obtained image suffers from a barrel-type spatial distortion, which results in an inconsistent measurement of object size and distance. Our distortion correction system with automatic calibration, based on least squares estimation, offers a better perception of size and distance from the endoscopic images. In order to examine the endoscopic maneuvering skills of the trainee, the automatic evaluation system is created. The system uses images from the exam procedure to verify the trainee skills. We use Support Vector Machine to classify endoscopic images of different regions in upper gastrointestinal tract. The experimental results on the distortion correction and image classification are reported. Simulator validation survey result from gastroenterology surgeons and fellows is included in this dissertation. A recommendation for further study is also enclosed.
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Surangsrirat, Decho. "Computer Integrated Endoscopic Simulator with Nonlinear Distortion Correction System." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_theses/147.
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The minimally invasive surgery or endoscopic surgery is the performance of surgery through a small incision with the aid of special medical equipment called a flexible endoscope. The advantage of this technique over open surgery is that there is significantly less operative trauma, resulting in less pain and shorter recovery time. Side effects of the surgery, such as the risk of infection, also reduce. Despite the tremendous benefits, surgeons require considerable practice and time to become competent in endoscopy. Traditionally, the procedure has been taught at the expense of patient comfort and safety as residents have performed the surgery under the supervision of physicians. Patients who undergo the endoscopies performed by students, particularly early in the training period, have been more likely to suffer more discomfort and prolonged procedures. Therefore, using the simulator becomes a promising alternative for endoscopic training process. Our approach is to integrate the computer system with a realistic mechanical model to create a computer-based simulator for upper endoscopy training. The simulator will cover the basics of flexible endoscopy and teach the student the skills required to perform the upper endoscopy. The mechanical training model that simulates a human upper gastrointestinal tract, including pathologies such as ulcers and polyps, will be built and integrated with computer software that will both help and evaluate the student. Due to the optical system of an endoscope, a barrel-type spatial distortion of the image is obtained which results in an inconsistent measurement of object size and distance. The distortion correction system, which includes automatic calibration and expansion coefficients calculation, offers a better perception of size and distance from the endoscopic images to the trainee. With the completion of the distortion correction system, an evaluation system including object recognition can be implemented with high accuracy. Finally, the results of visual observation and numerical analysis are discussed. A recommendation for further study is enclosed.
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Lu, I. "Smart knives : controlled cutting schemes to enable advanced endoscopic surgery." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1318091/.
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With the backdrop of the rapidly developing research in Natural Orifice Transluminal Endoscopic Surgery (NOTES), analysis of the literature supported the view that inventing new, controlled tissue dissection methods for flexible endoscopic surgery may be necessary. The literature also confirmed that white space exists for research into and the development of new cutting tools. The strategy of “deconstructing dissection” proposed in this thesis may provide dissection control benefits, which may help address the unique manoeuvring challenges for tissue dissection at flexible endoscopy. This assertion was supported by investigating six embodiments of the strategy which provided varying degrees of enhanced tissue dissection control. Seven additional concepts employing the strategy which were not prototyped also were offered as potential solutions that eventually might contribute evidence in defence of the strategy. One concept for selective ablation — dye-mediated laser ablation — was explored in-depth by theoretical analysis, experimentation and computation. The ablation process was found to behave relatively similar to unmediated laser ablation, but also to depend on cyclic carbonisation for sustained ablation once the dye had disappeared. An Arrhenius model of carbonisation based on the pyrolysis and combustion of wood cellulose was used in a tissue ablation model, which produced reasonable results. Qualitative results from four methods for dye application and speculation on three methods for dye removal complete the framework by which dye-mediated laser ablation might deliver on the promise offered by “deconstructing dissection”. Overall, this work provided the “deconstructing dissection” strategic framework for controlled cutting schemes and offered plausible evidence that the strategy could work by investigating embodiments of the scheme. In particular, dye-mediated laser ablation can provide selective ablation of tissue, and a theoretical model for the method of operation was offered. However, some practical hurdles need to be overcome before it can be useful in a clinical setting.
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Karimyan, Vahe. "Enhancement of spatial awareness in natural orifice transluminal endoscopic surgery." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/11084.
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Natural orifice transluminal endoscopic surgery (NOTES) represents a challenging concept to pursue in minimally invasive procedures, with a promise of becoming even less invasive, but with the additional issues of being team dependent and more technology intensive. The safety of patients undergoing any surgical procedure is of principal importance. When a surgeon performs laparoscopic procedures, he only has a two dimensional field of view and as a result, his spatial awareness is diminished. A surgeon operating under conditions of reduced spatial awareness poses an increased risk to a patient. Spatial awareness is deemed a necessary skill for the safe deployment of NOTES procedures. Understanding the surgeon’s situational and spatial awareness during NOTES investigation is therefore of paramount importance for the safe performance of this type of procedures. Enhancing scene visualisation, for instance by means of additional viewpoints or electromagnetic tracking, seems a feasible strategy for augmenting spatial awareness in NOTES. This study aims to propose novel approaches involving electromagnetic tracking and additional off-axis visualisation in an attempt to assess, as well as enhance spatial awareness of the operating field in NOTES. The original contributions of this thesis include: • Validation of an outlining approach to characterise spatial awareness in minimally invasive surgery particularly in NOTES • Qualitative and quantitative assessment of spatial awareness n NOTES • Identification of certain navigation behavioural patterns in NOTES • Design and evaluation of spatial awareness enhancement tool for NOTES The value of the research presented in this thesis, as well as the potential for further development is also discussed in the context of spatial awareness in MIS in general.
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Chan, Kin-wa, and 陳建華. "Transcriptomic approach to study the effect of polypectomy on human endometrial receptivity." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206559.
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Background: Endometrial polyps are common in women at reproductive ages, and found in more than 11% of infertile women. Hysteroscopic polypectomy is recommended to alleviating symptoms in patients with abnormal uterine bleeding. While the relationship between an endometrial polyp and subfertility is not clearly established, there is some evidence that hysteroscopic polypectomy may improve fertility outcome in IVF patients. Accumulating evidence suggested that elevated levels of activated mast cells as well as elevated matrix MMPs and cytokines levels in the patients who suffer from endometrial polyps. Moreover, significant increases in glycodelin levels were found in patients’ plasma and uterine. And there was a significant negative relationship between plasma glycodelin and progesterone levels in patients with endometrial polyps. To further understand whether hysteroscopic polypectomy affects endometrial microenvironment that is conductive to embryo implantation, we recruited 9 IVF patients and use microarray to compare their endometrial gene expressions before and after polypectomy. Methods: We investigated the change of endometrial gene expression patterns before and after polypectomy. Three out of 9 samples were subjected to microarray study. Quantitative-PCR (qPCR) was used to confirm the expression in all 9 samples, and compared with endometrial samples taken from patients underwent natural (LH+7 days, n = 8) and stimulated (hCG+7 days, n = 8) IVF cycles but without polyps. The outcome of subsequent IVF cycle was obtained to correlate the change of gene expression patterns. Results: Microarray analysis demonstrated that no genes are commonly differentially expressed in all 3 samples. One of the samples has shown very heterogeneous result. Sixteen genes (hERα, hERβ, OLFM1, OLFM2, IL15, CXCL14, GPX3, CCL4, UPKIB, PAEP, MMP26, SLC1A1, MUC15, MUC16, TM4SF4 and TFPI2) that are differentially expressed in any 2 of the samples and genes related to endometrial receptivity (OLFM1, IL15, CXCL14, GPX3, PAEP, MMP26, SLC1A1, MUC16) were selected for further analysis. We found that 3 samples have a gene expression pattern similar to natural cycle (LH+7 days) after polypectomy; while the other samples have a gene expression similar to the stimulated cycle (hCG+7 days). Clinical findings of the treated patients did not have strong correlation with pregnancy outcome. One out of two patients who had gene expression patterns similar to natural cycle got pregnant; while one out of seven patients who has gene expression patterns similar to stimulated cycle get pregnant after polypectomy. Conclusion: Polypectomy modulates endometrial gene expression patterns in some patients similar to those in natural cycles. However, our data did not support endometrial polypectomy significantly improved pregnancy outcome in the limited number of patient subjects (n=9) in this study.published_or_final_version
Obstetrics and Gynaecology
Master
Master of Medical Sciences
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Tate, David James. "Endoscopic Resection Of Early Neoplastic Colonic Lesions – Towards A Safe, Minimally-Invasive, Evidence-Based Endoscopic Alternative To Surgery." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20817.
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Colorectal cancer (CRC) arises from pre-malignant polyps, a process effectively interrupted by colonoscopic polypectomy (CP). Incomplete or poor-quality CP attenuates this effect. Large sessile colorectal polyps (≥20mm) [laterally spreading lesions – LSL] harbour a greater risk of malignancy versus smaller polyps but the majority can be safely and effectively removed in a single session by CP. This thesis contains four themes all relating to colonoscopic polypectomy. Theme 1 is entitled quality and safety in colonoscopic polypectomy. Within this theme Chapter 2 describes a published prospective imaging study of 141 sessile serrated polyps (SSP). The study concluded that the accuracy of a standardised protocol for endoscopic assessment of dysplasia within SSP was 95.0% as compared to the gold standard of blinded specialist gastrointestinal pathologists. This may be an important important tool for reducing rates of interval cancer after colonoscopy via the recognition and complete resection of dysplastic SSP. Chapter 3 contains a published pilot study of 41 SSP successfully removed using piecemeal cold snare polypectomy. There was no incidence of delayed bleeding or perforation. If confirmed in larger studies, this finding could reduce the burden of removing SSPs on patients and healthcare systems, particularly by the avoidance of clinically significant post-endoscopic bleeding. Chapter 4 contains a published study demonstrating that a simple score to determine the complexity of polypectomy (the SMSA score) could predict robust outcomes after polypectomy of large colorectal polyps. Lower SMSA scores (SMSA 2 versus 4) predicted a greater likelihood of EMR success (OR 13.34 [95% confidence interval {95% CI} 1.85-96.27]) and a lesser likelihood of adverse events including delayed bleeding (OR 0.36 [95% CI 0.22-0.58]), adenoma recurrence (OR 0.19 [95% CI 0.09-0.41]) and need for surgery at 2 weeks (OR 0.53 [95% CI 0.4-0.71]) (SMSA 3 versus 4). This information is highly relevant for patient consent since it can be determined by simple criteria known prior to the procedure, often present in referring endoscopy report. In addition, this data lends itself to the establishment of polyp-specific key performance metrics for those performing endoscopic resection. It can also be applied to time and resource management at an endoscopy unit level, for example to determine the estimated procedure length for a particular polyp or the suitability of a particular polyp for training purposes. Chapter 5 contains an unpublished study of the responses of 707 endoscopists in 7 countries to an online survey indicating that cold snare polypectomy is underutilised for diminutive and small polypectomy, submucosal invasive cancer is underappreciated by endoscopists and benign large colorectal polyps are routinely referred for surgery. Theme 2 is entitled refining the management of complex large colonic laterally spreading lesions (LSL). Within this theme Chapter 7 contains a published study of two-stage endoscopic mucosal resection. This describes a technique where, if a resection cannot be completed in a single session, the LSL may be removed at a second session within 2-3 months, with 81.8% of cases avoiding surgery to long-term follow up. Chapter 8 contains a published study on cold-forceps avulsion and adjuvant snare-tip soft coagulation (CAST). This is a simple cost-effective technique to resect non-lifting adenoma, a situation which often results in failed or incomplete resection of LSL. Of lesions completely resected using this technique, 99% eligible for surveillance avoided surgery to long-term follow up. Chapter 9 contains a published prospective study of LSL at the appendiceal orifice (AO). These LSL are traditionally described as difficult to resect endoscopically and are often an indication for surgery. The study demonstrated that if the distal margin of an LSL can be visualised within the AO and there is no endoscopic imaging evidence of submucosal invasive cancer that 91% of patients undergoing surveillance avoided surgery to a median of 18 months. Theme 3 is entitled mitigating recurrence after endoscopic resection of large colonic laterally spreading lesions. Within this theme Chapter 10 contains a published randomised controlled study of 400 lesions demonstrating that the technique of thermal ablation of the post EMR defect resection margin reduces the risk of polyp recurrence by four times. Chapter 11 contains a published study demonstrating that the temporal pattern of adenoma recurrence after EMR more likely if the LSL is ≥40mm in maximum dimension, contains high grade dysplasia or there was bleeding during the procedure requiring endoscopic control methods. Finally theme 4 is entitled future tools and methods for collaborative research in clinical endoscopic practice. Within this theme Chapter 12 contains details of a next-generation validated data collector for endoscopic resection procedures which in the future may allow greater collaboration between centres undertaking endoscopic resection, quality of data captured, correlation of endoscopic imaging, histologic and procedural data and the co-ordination of high quality observational and randomised studies. This thesis therefore contains 8 published studies that iterate the effectiveness of colonoscopic polypectomy. The future of the management of early neoplastic colonic lesions is endoscopic via an evidence-based patient and polyp specific approach.
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Cabras, Paolo. "3D Pose estimation of continuously deformable instruments in robotic endoscopic surgery." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAD007/document.
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Connaître la position 3D d’instruments robotisés peut être très utile dans le contexte chirurgical. Nous proposons deux méthodes automatiques pour déduire la pose 3D d’un instrument avec une unique section pliable et équipé avec des marqueurs colorés, en utilisant uniquement les images fournies par la caméra monoculaire incorporée dans l'endoscope. Une méthode basée sur les graphes permet segmenter les marqueurs et leurs coins apparents sont extraits en détectant la transition de couleur le long des courbes de Bézier qui modélisent les points du bord. Ces primitives sont utilisées pour estimer la pose 3D de l'instrument en utilisant un modèle adaptatif qui prend en compte les jeux mécaniques du système. Pour éviter les limites de cette approche dérivants des incertitudes sur le modèle géométrique, la fonction image-position-3D peut être appris selon un ensemble d’entrainement. Deux techniques ont été étudiées et améliorées : réseau des fonctions à base radiale avec noyaux gaussiens et une régression localement pondérée. Les méthodes proposées sont validées sur une cellule expérimentale robotique et sur des séquences in-vivoKnowing the 3D position of robotized instruments can be useful in surgical context for e.g. their automatic control or gesture guidance. We propose two methods to infer the 3D pose of a single bending section instrument equipped with colored markers using only the images provided by the monocular camera embedded in the endoscope. A graph-based method is used to segment the markers. Their corners are extracted by detecting color transitions along Bézier curves fitted on edge points. These features are used to estimate the 3D pose of the instrument using an adaptive model that takes into account the mechanical plays of the system. Since this method can be affected by model uncertainties, the image-to-3d function can be learned according to a training set. We opted for two techniques that have been improved : Radial Basis Function Network with Gaussian kernel and Locally Weighted Projection. The proposed methods are validated on a robotic experimental cell and in in-vivo sequences
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Kamedien, Mogammad Sauliegh. "Incidence of atrophic rhinitis after endoscopic sinonasal surgery : a retrospective review." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/13206.
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Includes bibliographical references.Sinonasal tumours have been resected endoscopically at Groote Schuur Hospital Cape Town South Africa since 2003. Surgery, although seen as minimally invasive because no external incisions are visible, is often very aggressive and destructive to the nasal structures. The removal of the nasal turbinates has always been seen as sacrilege due to the risk of developing atrophic rhinitis. If the theory regarding developing atrophic rhinitis after a simple turbinectomy stands true, one would expect a high incidence of atrophic rhinitis after radical resection of the sinonasal structures. This has not been our experience. METHODS: The study population includes a retrospective case review of all patients that had endoscopic sinonasal tumour resection by the same surgeon between 2006 and 2010. All patients were assessed for symptoms and signs suggestive of atrophic rhinitis up to two years post resection. RESULTS: 51 patients (34M: 17F) were included in the study. Patients with residual or recurrent tumour (n=19) and patients who had received adjuvant radiotherapy (n=17) had a statistically significant chance of developing symptoms and signs suggestive of atrophic rhinitis over time. Variables such as age, gender, extent of surgery, bilateral disease, benign or malignant tumour, were not statistically significant in the development of symptoms and signs suggestive of atrophic rhinitis over time. CONCLUSIONS: Atrophic rhinitis is not more common in patients who undergo endoscopic sinonasal surgery without adjuvant therapy. However, patients with residual tumour (after debulking surgery) or recurrent tumour and those who had received adjuvant radiotherapy had a statistically significant chance of developing symptoms and signs suggestive of atrophic rhinitis over time. Keywords: atrophic rhinitis, endoscopic resection, turbinectomy, medial maxillectomy, sinonasal tumours.
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Sdiri, Bilel. "2D/3D Endoscopic image enhancement and analysis for video guided surgery." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCD030.
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Grâce à l’évolution des procédés de diagnostiques médicaux et les développements technologiques, la chirurgie mini-invasive a fait des progrès remarquables au cours des dernières décennies surtout avec l’innovation de nouveaux outils médicaux tels que les systèmes chirurgicaux robotisés et les caméras endoscopiques sans fil. Cependant, ces techniques souffrent de quelques limitations liées essentiellement l’environnement endoscopique telles que la non uniformité de l’éclairage, les réflexions spéculaires des tissus humides, le faible contraste/netteté et le flou dû aux mouvements du chirurgien et du patient (i.e. la respiration). La correction de ces dégradations repose sur des critères de qualité d’image subjective et objective dans le contexte médical. Il est primordial de développer des solutions d’amélioration de la qualité perceptuelle des images acquises par endoscopie 3D. Ces solutions peuvent servir plus particulièrement dans l’étape d’extraction de points d’intérêts pour la reconstruction 3D des organes, qui sert à la planification de certaines opérations chirurgicales. C’est dans cette optique que cette thèse aborde le problème de la qualité des images endoscopiques en proposant de nouvelles méthodes d’analyse et de rehaussement de contraste des images endoscopiques 2D et 3D.Pour la détection et la classification automatique des anomalies tissulaires pour le diagnostic des maladies du tractus gastro-intestinal, nous avons proposé une méthode de rehaussement de contraste local et global des images endoscopiques 2D classiques et pour l’endoscopie capsulaire sans fil.La méthode proposée améliore la visibilité des structures locales fines et des détails de tissus. Ce prétraitement a permis de faciliter le processus de détection des points caractéristiques et d’améliorer le taux de classification automatique des tissus néoplasiques et tumeurs bénignes. Les méthodes développées exploitent également la propriété d’attention visuelle et de perception de relief en stéréovision. Dans ce contexte, nous avons proposé une technique adaptative d’amélioration de la qualité des images stéréo endoscopiques combinant l’information de profondeur et les contours des tissues. Pour rendre la méthode plus efficace et adaptée aux images 3Dl e rehaussement de contraste est ajusté en fonction des caractéristiques locales de l’image et du niveau de profondeur dans la scène tout en contrôlant le traitement inter-vues par un modèle de perception binoculaire.Un test subjectif a été mené pour évaluer la performance de l’algorithme proposé en termes de qualité visuelle des images générées par des observateurs experts et non experts dont les scores ont démontré l’efficacité de notre technique 3D d’amélioration du contraste. Dans cette même optique,nous avons développé une autre technique de rehaussement du contraste des images endoscopiques stéréo basée sur la décomposition en ondelettes.Ce qui offre la possibilité d’effectuer un traitement multi-échelle et d’opérer une traitement sélectif. Le schéma proposé repose sur un traitement stéréo qui exploite à la fois l’informations de profondeur et les redondances intervues,ainsi que certaines propriétés du système visuel humain, notamment la sensibilité au contraste et à la rivalité/combinaison binoculaire. La qualité visuelle des images traitées et les mesures de qualité objective démontrent l’efficacité de notre méthode qui ajuste l’éclairage des images dans les régions sombres et saturées et accentue la visibilité des détails liés aux vaisseaux sanguins et les textures de tissuesMinimally invasive surgery has made remarkable progress in the last decades and became a very popular diagnosis and treatment tool, especially with the rapid medical and technological advances leading to innovative new tools such as robotic surgical systems and wireless capsule endoscopy. Due to the intrinsic characteristics of the endoscopic environment including dynamic illumination conditions and moist tissues with high reflectance, endoscopic images suffer often from several degradations such as large dark regions,with low contrast and sharpness, and many artifacts such as specular reflections and blur. These challenges together with the introduction of three dimensional(3D) imaging surgical systems have prompted the question of endoscopic images quality, which needs to be enhanced. The latter process aims either to provide the surgeons/doctors with a better visual feedback or improve the outcomes of some subsequent tasks such as features extraction for 3D organ reconstruction and registration. This thesis addresses the problem of endoscopic image quality enhancement by proposing novel enhancement techniques for both two-dimensional (2D) and stereo (i.e. 3D)endoscopic images.In the context of automatic tissue abnormality detection and classification for gastro-intestinal tract disease diagnosis, we proposed a pre-processing enhancement method for 2D endoscopic images and wireless capsule endoscopy improving both local and global contrast. The proposed method expose inner subtle structures and tissues details, which improves the features detection process and the automatic classification rate of neoplastic,non-neoplastic and inflammatory tissues. Inspired by binocular vision attention features of the human visual system, we proposed in another workan adaptive enhancement technique for stereo endoscopic images combining depth and edginess information. The adaptability of the proposed method consists in adjusting the enhancement to both local image activity and depth level within the scene while controlling the interview difference using abinocular perception model. A subjective experiment was conducted to evaluate the performance of the proposed algorithm in terms of visual qualityby both expert and non-expert observers whose scores demonstrated the efficiency of our 3D contrast enhancement technique. In the same scope, we resort in another recent stereo endoscopic image enhancement work to the wavelet domain to target the enhancement towards specific image components using the multiscale representation and the efficient space-frequency localization property. The proposed joint enhancement methods rely on cross-view processing and depth information, for both the wavelet decomposition and the enhancement steps, to exploit the inter-view redundancies together with perceptual human visual system properties related to contrast sensitivity and binocular combination and rivalry. The visual qualityof the processed images and objective assessment metrics demonstrate the efficiency of our joint stereo enhancement in adjusting the image illuminationin both dark and saturated regions and emphasizing local image details such as fine veins and micro vessels, compared to other endoscopic enhancement techniques for 2D and 3D images
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Wilson, William. "Surgical training with an augmented digital environment (SurgADE) an adaptable approach for teaching minimally invasive surgery techniques /." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0006300.
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VOLPATTO, SILVIO. "Robotic technology and endoluminal surgery in digestive surgery." Doctoral thesis, Politecnico di Torino, 2018. http://hdl.handle.net/11583/2709912.
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BACKGROUND. Colorectal cancer (CRC) is the third most common cancer in males and second in females, and the fourth most common cause of cancer death worldwide. The implementation of screening programs has allowed to the identification of an increasing number of early-stage neoplastic lesions. Presently, superficial colorectal neoplasms (including precancerous lesions and early cancer) can be resected in the colon by Endoscopic Mucosal Resection (EMR) and Endoscopic Submucosal Dissection (ESD), while in the rectum by Transanal Endoscopic Microsurgery (TEM). They are the preferred choices inside of the minimally invasive panorama regarding the CRC treatment. TEM technique offers more advantages than EMR and ESD, but it can’t overcome the recto-sigmoid junction. Many authors, research institutes and biomedical industries have proposed different solutions for microsurgery dissection of early lesions in the colon, but all these proposals have in common the development of platforms expressly designed for this use, with significant purchasing and management costs. The aim of our research project is to develop a robotic platform that allows to treat lesions throughout the colon limiting the costs of management and purchasing. This new robotic platform, developed in collaboration with Scuola Superiore Sant’Anna in Pisa, is called RED (Robot for Endoscopic Dissection). At the tip of a standard endoscope a hood (RED) is placed. RED is equipped by two extractable teleoperated robotic arms (i.e., diathermic hook and gripper); their motion is provided by onboard miniaturized commercial motors and a dedicated external platform. The endoscopist holds the endoscope near the lesion, while the operator drives the robotic arms through a remote control.
MATERIALS AND METHODS. Several preliminary studies have been conducted in the following order. A first test was conducted for identification of force value for lifting and pulling maneuvers using a modified TEM instrument. A CAD study was conducted to determine the maximum size that the hood must have in order to overcome the critical angle represented by the splenic flexure. Several tests were conducted to determine the degrees of freedom of each robotic arm, starting with the CAD drawing to make subsequently the mock-ups of each configuration. Finally, a 3D mock-up was produced that was assembled on an endoscope to perform the in vitro test to evaluate the workspace and field of view using a pelvic trainer for TEM.
RESULTS. The first test shown that the minimum force that the gripper will have to develop with the push-pull is 1.5N. The CAD study shown that the maximum dimensions the hood must have to overcome splenic flexure are: maximum diameter 28mm, maximum length 57mm. After several configurations was been tested, the final prototype features are: gripper arm with pitch sliding and open/close of the tip and diathermic hook arm with pitch, roll and sliding. There will be 6 such distributed motors: 3 external motors for the gripper arm that will operate through cables contained in a sheath adherent to colonscope and 3 embedded motors for diathermic hook arm (one integrated on the hood for the sliding degree of motion and the other two inside of the arm). The in-vitro test has been carried out to evaluate the workspace and they proved that the operating field vision is not obstructed by the hood and the working range is sufficiently wide to perform a dissection.
CONCLUSION. Tests conducted up to this point have allowed us to identify the overall layout of the RED: dimensions, degrees of freedom, number and distribution of motors needed for the operation of robotic arms; moreover, it is proved that the device, once assembled, maintained the visual and operational field characteristics necessary to perform an accurate dissection. The next step will be to realize a RED steel final prototype and in-vivo tests will be carry out to replicate an endoscopic dissection into the colon.
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Lau, Hung. "Endoscopic totally extraperitoneal inguinal hernioplasty : techniques and advances for optimal outcome." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36425242.
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Thomson, David Alexander. "The role of endoscopic retrograde pancreatography in the management of pancreatic trauma." Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/14312.
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Background: Endoscopic retrograde pancreatography (ERP) has various applications in the diagnosis and management of pancreatic trauma. The utility of ERP in pancreatic trauma presenting to a level 1 equivalent trauma centre was analysed. Methods: Patients who sustained pancreatic trauma and underwent ERP were identified. Patient demographics, mechanism of injury, time to presentation, diagnostic modalities, associated injuries, clinical management, endoscopic interventions and their timing, surgical treatment and patient outcomes were recorded. Results: Forty-eight patients with pancreatic trauma were referred for ERP after blunt (26), gunshot (15), or stab (7) injury. The average time from injury to ERP was 38 days (range 2 – 365). An ERP visualized the duct in 47 patients. Twenty-four patients had a pancreatic fistula, 12 patients had a main pancreatic duct stricture or cut-off and 10 patients had a pseudocyst. Endoscopic interventions were pancreatic duct sphincterotomy (15), pancreatic duct stent (7) or pseudocyst drainage (6). Ten patients demonstrated minor injuries and no interventions were performed. One patient had a normal pancreatogram. Ten patients required pancreatic surgery following ERP (distal pancreatectomy n=6, pancreaticojejenostomy n=3 and cystjejenostomy n=1). One patient unable to tolerate ERP had a distal pancreatectomy. Conclusion: The majority of ERPs were performed post surgery or after a delayed presentation. Diagnostic success was high and in conjunction with therapeutic interventions 77% of patients avoided surgery for their pancreatic complications. ERP is an effective tool in the delayed management of the local complications of pancreatic trauma.
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Ali, Mahmoud El-Sayed. "Mucin gene expression in chronic sinusitis patients undergoing functional endoscopic sinus surgery." Thesis, University of Newcastle upon Tyne, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246606.
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Khatri, Hershil. "Modelling the effects of middle meatal synechiae post-endoscopic sinus surgery using computational fluid dynamics (CFD) and virtual surgery." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29534.
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Chronic rhinosinusitis (CRS) is a common sinonasal condition carrying a significant disease burden. Functional endoscopic sinus surgery (FESS) is often indicated where medical management fails. Middle turbinate lateralisation and adhesion formation (MiTLAF) is a common cause of failed FESS. Various MiTLAF prevention techniques have been described in the literature; however, no studies objectively analyse the physiological sequelae. This thesis reviews the literature regarding MiTLAF prevention techniques to determine the most efficacious and safe technique(s). As a proof of concept, computational fluid dynamics (CFD) analysis was employed to model aerodynamic changes occurring in the presence of MT synechiae.
Systematic review was performed following the PRISMA guidelines. The effects of post-operative MT synechiae on airflow velocity and streamlines, temperature, and relative humidity levels were done using CFD. A three-dimensional sinonasal model was segmented from the data, and virtual surgery was performed to simulate a full-house functional endoscopic sinus surgery. Multiple synechiae models were virtually created in locations to reflect those most commonly seen in clinical practice. CFD analysis was performed on each model, in comparison with a control model without synechiae. Mass-weighted averages for airflow velocity, relative humidity and mucosal temperature were recorded to assess for dynamic changes in the presence of synechiae.
The reviewed literature suggests that silastic splints and conchopexy are most safe and effective in MiTLAF prevention. CFD analysis demonstrated aberrant downstream airflow in all models. There was reduced airflow and increased air temperature/humidity in ipsilateral frontal, ethmoid and sphenoid sinuses with increased airflow velocity and reduced air/mucosal surface temperature in a concentrated central “jet” in the middle meatus. Effects were more significant with larger synechia. Bulk inspired airflow at the nasopharynx was largely unaffected. These findings may explain the persistent symptoms seen in post-FESS CRS patients with MT synechiae and reinforce the importance of prevention and adhesiolysis. Further studies with multiple models of actual post-FESS patients with synechiae are required to validate these findings.
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Agrawal, Ankur S. "Automating endoscopic camera motion for teleoperated minimally invasive surgery using inverse reinforcement learning." Digital WPI, 2018. https://digitalcommons.wpi.edu/etd-theses/1252.
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During a laparoscopic surgery, an endoscopic camera is used to provide visual feedback of the surgery to the surgeon and is controlled by a skilled assisting surgeon or a nurse. However, in robot-assisted teleoperated systems such as the daVinci surgical system, the same control lies with the operating surgeons. This results in an added task of constantly changing view point of the endoscope which can be disruptive and also increase the cognitive load on the surgeons. The work presented in this thesis aims to provide an approach that results in an intelligent camera control for such systems using machine learning algorithms. A particular task of pick and place was selected to demonstrate this approach. To add a layer of intelligence to the endoscope, the task was classified into subtasks representing the intent of the user. Neural networks with long short term memory cells (LSTMs) were trained to classify the motion of the instruments in the subtasks and a policy was calculated for each subtask using inverse reinforcement learning (IRL). Since current surgical robots do not enable the movement of the camera and instruments simultaneously, an expert data set was unavailable that could be used to train the models. Hence, a user study was conducted in which the participants were asked to complete the task of picking and placing a ring on a peg in a 3-D immersive simulation environment created using CHAI libraries. A virtual reality headset, Oculus Rift, was used during the study to track the head movements of the users to obtain their view points while they performed the task. This was considered to be expert data and was used to train the algorithm to automate the endoscope motion. A 71.3% accuracy was obtained for the classification of the task into 4 subtasks and the inverse reinforcement learning resulted in an automated trajectory of the endoscope which was 94.7% similar to the human trajectories collected demonstrating that the approach provided in thesis can be used to automate endoscopic motion similar to a skilled assisting surgeon.
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Viebig, Elisabeth [Verfasser]. "NOTES "Natural Orifice Transluminal Endoscopic Surgery" : Vorstellungen und Meinungen unterschiedlicher Fachdisziplinen / Elisabeth Viebig." Gießen : Universitätsbibliothek, 2013. http://d-nb.info/1065462557/34.
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Goncalves, Nicholas. "Transorbital Endoscopic Surgery for Sphenoid Wing Meningioma: Long-term Outcomes & Surgical Technique." Master's thesis, Faculty of Health Sciences, 2020. http://hdl.handle.net/11427/32268.
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Sphenoid wing meningiomas are benign tumors that result in proptosis, visual impairment and pain. Traditional open surgical approaches are associated with significant morbidity. Transorbital endoscopic surgery has been developed as a minimally invasive approach to gain access to these tumors and address the main presenting symptoms. The aim of the study was to assess long term vision and proptosis outcomes in patients undergoing a transorbital endoscopic resection of sphenoid wing meningioma using a combined endonasal, precaruncular and extended superior eyelid approach and to describe the surgical approach. Materials & Methods A retrospective chart review was conducted in 21 patients with lateral sphenoid wing meningioma at Groote Schuur Hospital & Cape Town Mediclinic from 2015–2019. All patients had undergone a transorbital endoscopic subtotal resection (Simpson grade II – IV) by the same surgical team. Vision was assessed using a Snellen chart and proptosis measured in mm using a Hertel exophthalmometer by an ophthalmologist. Measurements were taken at 6 weeks, 6 months and at 1 year postoperatively and compared to pre-operative values. Patients were categorized according to the WHO classification of vision into group A (blind), group B (low vision) & group C (normal vision) according to their pre-operative visual acuity. Nonparametric statistical tests employing the Wilcoxon Signed-Ranks Test were used for analysis. Statistical significance was determined by a confidence interval of 0.95, p = < 0.05 for both visual acuity (converted to LogMar) and proptosis in mm. Results A total of 21 patient charts were reviewed. The mean age of presentation was 48.8 years (range 34-79 years), and the majority of patients were female (20/21 = 95%). The most common presenting complaints were loss of vision (100%), proptosis (95%) and headache (76%). Preoperative visual results were as follows: 10 (48%) in group A (blind), 4 (19%) in group B (low vision) and 7 (33%) in group C (normal vision). In group A, 6 (60%) remained unchanged, 2 (20%) deteriorated & 1 (10%) improved. In group B, 3 (75%) improved, and 1 (25%) remained stable. In group C, 5 (71%) improved and 2 (29%) remained stable. Vision in groups B & C showed no deterioration. Patients in group A showed no benefit from optic nerve decompression. Vision in groups B & C showed a statistically significant improvement at 6 weeks [95% CI] (p = 0.021). This trend extended to long term follow up at 6 months [95% CI] (p= 0.021) and 1 year [95% CI] (p = 0.0054) postoperatively. Proptosis initially decreased, proving statistical significance at 6 weeks [95% CI] (p = 0.0054) postoperatively. The decrease at 6 months (p = 0.08) was not statistically significant and trended towards an increase in proptosis by 1 year (p = 0.78) postoperatively. The mean hospital stay was 2.7 days (range 2 – 4 days). The majority of tumors were histologically classified as WHO grade I. Conclusion Endoscopic medial optic canal decompression prior to transorbital multiportal surgery for sphenoid wing meningioma stabilizes or improves visual acuity for at least 1 year. Lateral orbitotomy via a superior eyelid approach and subtotal tumor resection initially decreases proptosis, but in the long term, returns to its preoperative state by 1 year if the main tumor component is not addressed. The earlier that medial optic nerve decompression is performed and the better the preoperative visual acuity, the greater the likelihood of favorable long-term visual outcomes.
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TOLLNER, ALISON MARIE. "DIVIDED ATTENTION DURING ADAPTATION TO VISUAL-MOTOR ROTATION IN AN ENDOSCOPIC SURGERY SIMULATOR." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1061235487.
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Amanov, Ernar [Verfasser]. "Designing a robotic port system for laparo-endoscopic single-site surgery / Ernar Amanov." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2019. http://d-nb.info/1219652229/34.
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Christiane, Peter-John. "Development of a minimally invasive robotic surgical manipulator /." Link to the online version, 2008. http://hdl.handle.net/10019/2249.
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Chun, Mei-yee Elke, and 秦美兒. "Comparing Hong Kong market experience with the market development in China in minimally invasive surgery." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31268778.
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Höller, Kurt [Verfasser]. "Novel Techniques for Spatial Orientation in Natural Orifice Translumenal Endoscopic Surgery (NOTES) / Kurt Höller." Aachen : Shaker, 2011. http://d-nb.info/1098041984/34.
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Chen, Min Si. "Calibration and registration of an image enhanced surgical navigation system for endoscopic sinus surgery." Thesis, University of East Anglia, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.439900.
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Luck, A. J. "The application of new technology to colorectal surgery / by Andrew James Luck." c1999, 1999. http://hdl.handle.net/2440/38360.
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Includes bibliography (leaves 249-291).xxiv, 291, [52] leaves :
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
Discusses and evaluates the role of intra-operative ultrasound in colorectal surgery ; techniques of laparoscopic surgery and the impact on the incidence of hypothermia during surgery ; advanced prognostic techniques in colorectal cancer ; the impact of ambulatory anorectal surgery ; and, the potential of an information video to decrease the anxiety of patients through imparting essential information to patients.
Thesis (M.D.)--University of Adelaide, Dept. of Surgery, 1999
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Chan, Balwin Man Hong. "A miniaturized 3-D endoscopic system using active stereo-vision /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202002%20CHANB.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002.Includes bibliographical references (leaves 106-108). Also available in electronic version. Access restricted to campus users.
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Yu, Tin-men, and 余天敏. "An evidence-based patient education intervention to reduce pre-procedural anxiety." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44627105.
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Ахтирська, А. О. "Відновлення репродуктивної функції жінок ендоскопічним методами." Thesis, Сумський державний університет, 2017. http://essuir.sumdu.edu.ua/handle/123456789/58593.
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Chen, Kehui. "Powering of endoscopic cutting tools for minimally invasive procedures." Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-theses/887.
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" Sample cutting is an important minimally invasive medical procedure. Currently there are several types of medical devices used to cut a distal biological sample, for example, a video endoscope and TurboHawk Plaque Excision Systems. Directional Atherectomy (DA) with the TurboHawk Plaque Excision Systems is a catheter-based, minimally invasive treatment method for peripheral arterial disease (PAD). During a procedure, a catheter is directed toward an area of plaque buildup to remove the plaque from the body, restoring blood flow (Covidien, 2013). Endoscopy is an important procedure used in the medical field to study and diagnose different parts of a body without the need to undergo a major surgery. The major devices are a video endoscope with a flexible or rigid insertion tube and endoscopic therapy devices. Arrays of the devices, through the instrument channel in the insertion tube of endoscopes, to perform a variety of functions are offered. The biological sample cut is one of the important endoscopic therapies. Both of Directional Atherectomy and endoscopy procedures require a power transmission from the proximal tip of device to the distal end, where the cutter is located, for cutting a sample. However, the working length is up to meters, and the diameter of the devices is in millimeter scale in the minimally invasive surgery. Thus enough power transmitting to the distal end of the device for the biological sample cutting is crucial. This research presents the effort toward the investigation of the potential power mechanisms from the proximal tip to the cutter at the distal end of the device for rapid rotational cutting motion to improve the cutting efficiency and accuracy. In this thesis, the potential powering mechanisms including fluid, electrical, and torque coils are investigated. Since the transmission power is used for a rotational cutting action, and the cutting geometry has influence on the cutting power, thus this research also focuses on the analysis of the cutting geometry for the rotational sample cutting. The Hertz contact theory and von Mises yield criterion are used to find the influence of tool geometry on the material removing process, as well as Abaqus, a commercial FEM software, is used for the finite element analysis. Fiber-reinforced composite structures are the main characteristic of the representative biological sample, and their mechanical behavior is strongly influenced by the concentration and structural arrangement of constitute such as collagen and elastin. Researches show that the biological sample, for example, a soft biological sample, has hyperelastic properties and behave anisotropically, and there are a few publications about the plastic properties and cutting mechanics. Thus a linear elastic and linear plastic material model is defined for the finite element analysis of material removal. The analytical results and finite element results both show that as the tool rake angle increases or the tool angle decreases, the magnitude of cutting force decreases. A preliminary representative sample cutting experiment was conducted, and standard cutters with different cutting geometries were tested in order to find the characteristic of the biological sample cutting and the influence of tool geometry on the required cutting power. The experiments reveal the same conclusions as the analytical and finite element results. "
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Lindström, Pernilla. "A Study on Endoscopic Live Donor Nephrectomy and Elevated Intraperitoneal Pressure." Doctoral thesis, Uppsala University, Department of Surgical Sciences, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2969.
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Live donor nephrectomy (LDN) is a unique surgical challenge where surgery is performed on healthy individuals. It is of great importance to keep the morbidity of donors as low as possible, as well as harvesting a kidney in optimal condition. Lowering morbidity is the motive for introducing the endoscopic technique in LDN. Oliguria and impaired kidney function can, however, be seen during pneumoperitoneum and endoscopic LDN have been criticized for not yet being proven safe enough.
The aims of this study were to investigate the changes in renal function during elevated intraabdominal pressure (IAP) in donors and rats and to evaluate donor morbidity and safety of the new endoscopic techniques compared to the open LDN.
In two studies, a rat model was used. It was found that elevation of IAP diminished glomerular filtration rate (GFR). Cardiac output (CO) and renal blood flow decreased as well. Elevation of IAP activates the renin system and aldosterone was increased. Acute angiotensin II receptor 1 blockade (candesartan) treatment lowered blood pressure significantly and impaired renal function during elevated IAP. Volume expansion prior to, and during, pneumoperitoneum reduces the deleterious effects on renal function.
Three studies on kidney live donors show that traditional laparoscopic surgery (TLS) takes longer time to perform than open LDN. Hand-assistance facilitates the operation and increases the safety margin as well as shortens the operation by 27% compared to TLS. Evaluation of a hand-assisted retroperitoneoscopy (HARS), performed for the first time ever in Uppsala 2001, show that the operation is short and safe, the donors experience little pain and the renal function is favourable compared to open surgery, TLS and hand-assisted transperitoneal laparoscopic approaches.
In conclusion, the results indicate that elevated IAP decreases GFR due to decreased CO and activation of the RAAS, which can be avoided with adequate hydration. Endoscopy can be facilitated if hand-assistance is applied and in particular hand-assisted retroperitoneoscopic nephrectomy shows advantages for the donor.
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Shaw, Chi-kee Leslie. "Evaluation of sheep model with regard to healing of nasal epithelium after endoscopic sinus surgery." Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09MS/09mss534.pdf.
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Bibliography: leaves 109-125. This thesis validated the use of sheep as a suitable animal model to study endoscopic sinus surgery (ESS) and to evaluate factors that may play a role in the healing of nasal epithelium after surgery. Nasal packing was shown to cause a significant injury and should be used by ESS surgeons with caution. Full-thickness wounds should be avoided in the nose where possible as the re-ciliation was significantly reduced when compared to partial-thickness wounds. In addition the healing of the nose took significantly longer than previously thought and was incomplete 84 days after surgery. Scanning electron microscopy was shown to be an important outcome measure for the healing of the nasal mucosa after ESS and a new technique for measuring the re-ciliation was validated.
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Mourad, Mohammed [Verfasser], and Marcos [Akademischer Betreuer] Tatagiba. "Endoscopic assisted surgery of posterior skull base. Analysis of the advantages / Mohammed Mourad ; Betreuer: Marcos Tatagiba." Tübingen : Universitätsbibliothek Tübingen, 2017. http://d-nb.info/1199615145/34.
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Bessell, Justin Raymond. "The development, validation and analysis of new endosurgical procedures in upper gastrointestinal surgery /." Title page, table of contents and summary only, 1995. http://web4.library.adelaide.edu.au/theses/09MD/09mdb557.pdf.
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Leung, Wing-ki Vikki, and 梁頴琪. "The implications of transcatheter aortic valve implantation (TAVI) adoption." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48424031.
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Aortic stenosis is a life-threatening valvular heart disease. At the onset of symptoms, a patient’s prognosis becomes poor and the risk of death rapidly increases. Aortic valve replacement surgery remains the gold standard in treatment for aortic stenosis. However, in the total population of patients with severe aortic stenosis, about one third are deemed inoperable due to their high surgical risk. In recent years, the development of transcatheter aortic valve implantation (TAVI), a non-invasive heart valve replacement procedure brought hope for the elderly, high-risk and inoperable aortic stenosis patient population pool. A literature review was performed to examine the safety, efficacy and effectiveness evidence for transcatheter aortic valve treatment option. The results showed that TAVI is a safe treatment option, however the effectiveness for the whole patient population is unknown. The adoption of this alternative treatment option is certainly coupled with multiple dimension of impact from a public health perspective. It remains inconclusive whether TAVI is an effective treatment option to be adopted.published_or_final_version
Public Health
Master
Master of Public Health
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Nondela, Babalwa Bukeka. "Correlation of 99mTc Sucralfate scan and endoscopic grading in caustic oesophageal injury: An observational analytic study at Red Cross War Memorial Children’s Hospital." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29701.
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Introduction: Technecium (Tc) 99m Sucralfate scan has been shown to be a reliable and non-invasive screening modality after caustic substance ingestion, followed by oesophagoscopy under general anaesthesia to grade the extent and severity of injury. Aim: To determine a correlation between the 99mTc Sucralfate scan and the endoscopy findings in children presenting with caustic oesophageal injury. Methods: An observational analytic study of children who had both 99mTc Sucralfate scan and endoscopy after caustic substance ingestion at Red Cross War Memorial Children’s Hospital in a period between January 2009 and September 2016. The oesophageal injury was classified into low grade and high grade according to the degree of adhesion on 99mTc Sucralfate scan and modification of Zargar endoscopic grading. Approval of the study by the University of Cape Town Faculty of Health Sciences Human Research Ethics Committee was obtained, REF. 049/2017. Results: Out of a total of 197 children, 40 children were identified who had both investigations done on average 26hours post injury. Low grade adhesion on 99mTc Sucralfate scan was found in 27 children (68%), and all had low grade Zargar’s oesophageal injuries. None of these subsequently developed residual pathology. Thirteen had high grade adhesion and five of these had high grade injury on endoscopy. Three (23%) developed oesophageal strictures. Correlation of 99mTc Sucralfate and endoscopic findings reached statistical significance with a p-value of 0.0014. No morbidity was associated with either the scan or endoscopy. Conclusions: Low grade Sucralfate scan finding has potential to successfully eliminate the need for invasive endoscopy under general anaesthesia and thereby reducing procedure related morbidity, hospitalization and associated costs. However, mandatory endoscopy is required in children with high grade adhesion seen on 99mTc Sucralfate scan. This requires confirmation using a larger prospective study.
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Nakamura, Tatsuro. "Revisiting the infracardiac bursa using multimodal methods: topographic anatomy for surgery of the esophagogastric junction." Kyoto University, 2020. http://hdl.handle.net/2433/253166.
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Dirksen, Carmen Desirée. "Medical technology assessment of endoscopic surgery costs, effects and diffusion of laparoscopic cholecystectomy and laparoscopic inguinal hernia repair /." [Maastricht : Maastricht : Universiteit Maastricht] ; University Library, Maastricht University [Host], 1998. http://arno.unimaas.nl/show.cgi?fid=8252.
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Osada, Hiroaki. "Novel device prototyping for endoscopic cell sheet transplantation using a three-dimensional printed simulator." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263545.
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Tanji, Masahiro. "Impact of Intraoperative 3-Tesla MRI on Endonasal Endoscopic Pituitary Adenoma Resection and a Proposed New Scoring System for Predicting the Utility of Intraoperative MRI." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/264635.
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京都大学新制・論文博士
博士(医学)
乙第13419号
論医博第2227号
新制||医||1052(附属図書館)
京都大学大学院医学研究科脳統御医科学系専攻
(主査)教授 高橋 淳, 教授 中本 裕士, 教授 大森 孝一
学位規則第4条第2項該当
Doctor of Medical Science
Kyoto University
DFAM
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Dray, Xavier. "Evaluation et optimisation des techniques d'abord transgastrique de la cavité péritonéale en chirurgie endoscopique transluminale par les orifices naturels (natural orifice translumenal endoscopic surgery, notes)." Paris, CNAM, 2009. http://www.theses.fr/2009CNAM0672.
Full textAbstract:
NOTES (Natural Orifice Translumenal Endoscopic Surgery) is a surgical technique that aims to gain access to the peritoneal cavity with a flexible endoscope, through a natural orifice and through the wall of the digestive or urogenital tract. Mastering the per-oral transgastric route (available to both genders, as opposed to the transvaginal route) is an important challenge for the development of this technique. The studies presented in this thesis demonstrate the feasibility of transgastric endoscopic procedures in a live porcine model. This work emphasizes: (1) the need for a prevention of infection prior to transgastric NOTES procedures; (2) the interest of a preliminary pneumoperitoneum before the creation of the transgastric access, to prevent any damage of the surrounding organs; (3) the safe use of a balloon-dilation technique for creation of the transgastric access, as compared to the use of a sphincterotome-incision ; (4) the feasibility of intraperitoneal delivery of sterile prothetic material during NOTES, as illustrated by the transgastric NOTES ventral hernia repair technique; (5) the need for technological improvement for safe, quick and reliable transgastric access to the peritoneal cavity (for example by using a 2 µm wavelength laser) and gastrotomy closure (for example with hemoclips, threaded-tagsLa NOTES (Natural Orifice Translumenal Endoscopic Surgery) est une technique chirurgicale qui consiste à aborder la cavité péritonéale à l’aide d’un endoscope souple, à travers les orifices naturels puis à travers la paroi du tube digestif ou des voies uro-génitales. La maîtrise d’un abord per-oral et transgastrique (disponible pour les deux sexes, par opposition à l’abord transvaginal) est un objectif hautement souhaitable pour le développement de cette technique. Les travaux présentés dans cette thèse démontrent la faisabilité d’interventions endoscopiques souples par voie transgastrique sur modèle porcin vivant. Ils mettent en évidence : (1) l’intérêt de protocoles anti-infectieux avant une NOTES transgastrique ; (2) la nécessité de réaliser un pneumopéritoine avant création d’un abord transgastrique pour prévenir la survenue de plaies d’organes de voisinage; (3) la meilleure tolérance d’une dilatation au ballon plutôt que d’une incision au sphinctérotome lors de la création de la voie d’abord transgastrique ; (4) la possibilité d’introduire de façon stérile par voie transgastrique du matériel prothétique pour un usage intrapéritonéal (telle qu’illustrée par une technique de cure d’éventration ombilicale par NOTES transgastrique) ; (5) le caractère encore imparfait et hautement dépendant des avancées technologiques des méthodes endoscopiques de création (par exemple à l’aide d’un laser de 2 µm de longueur d’onde) et de fermeture (par exemple par clips, points en T, agrafes) de la voie d’abord transgastrique ; et (6) la faisabilité de tests d’étanchéité mini-invasifs et hautement spécifiques (utilisant par exemple de l’hydrogène dilué)