Thesis (M.D.) -- University of Adelaide, Dept. of Surgery, 2000. / Includes bibliographical references.

Thesis (M.A.Sc.) - Simon Fraser University, 2007. / Theses (School of Engineering Science) / Simon Fraser University. Also issued in digital format and available on the World Wide Web.

Orientador: Wilter Ricardo Russiano Vicente / Coorientador: Aracélle Elisane Alves / Banca: Eliandra Antônia Pires Buttler / Banca: Marcelo Marcondes Seneda / Resumo: O sucesso da produção in vitro de embriões requer a utilização de uma técnica de recuperação eficiente de oócitos, e os melhores resultados têm sido obtidos pela aspiração laparoscópica. O objetivo deste trabalho foi avaliar os efeitos de sucessivas sessões de aspirações foliculares na quantidade, qualidade e capacidade de maturação in vitro de oócitos obtidos de ovelhas submetidas à estimulação hormonal prévia (80 mg FSH + 300 UI eCG). Foram selecionadas seis ovelhas (n=6) da raça Santa Inês, as quais foram submetidas a nove sessões de aspiração folicular por vídeolaparoscopia com intervalo de sete dias, totalizando 56 aspirações. Ao final do período de cultivo de 24 horas, os oócitos foram corados e classificados quanto ao estádio de maturação nuclear e citoplasmática. A taxa de recuperação foi de 61,4±2%, observando-se ausência de variação entre as sessões (p>0,05), e a média de oócitos recuperados por fêmeas de 6,4±2 por semana, com um total de 249 oócitos recuperados, sendo a média de 42±4 oócitos por fêmea no total das apirações. Não houve diferença significativa entre a classificação da maturação nuclear (p=0,937), mas sim entre a maturação citoplasmática (p<0,0001), entretanto não foi observado variação estatística entre as semanas quanto a maturação nuclear (p=0,908) e a maturação citoplasmática (p=0,792). Concluímos que após nove sessões consecutivas de aspiração folicular o número e a qualidade dos oócitos recuperados permaneceram constantes assim como as taxas obtidas de maturação nuclear e citoplasmática, demonstrando a viabilidade desta técnica para repetidas aspirações foliculares em uma mesma doadora / Abstract: The success of in vitro production requires an effective collection technique as well as an efficient oocyte recovery. In addition, the best results have been applied for using laparoscopic aspiration. The aim of the present study was to evaluate if successive follicle aspiration sessions may interfere on quantity, quality and in vitro maturation of oocytes recovery from ewes submitted to hormonal stimulation. Santa Ines ewes (n=6) were submitted to a total of nine sessions (one session per week) of follicle aspiration performed by videolaparoscopy. The oocytes from each session were classified in according to quality and to in vitro maturation capacity. Nuclear and citoplasmatic maturation were assessed. The recovery rate was 61,39±19,97%, with no variation among the sessions (p>0,05) and the mean of recovered oocytes per ewe was 6,36±2,0 per week. There was no significant difference among nuclear maturation classification (p=0,937), but there was significant difference among citoplasmatic maturation (p<0,0001). There was no statistical variation among weeks to nuclear maturation (p=0,908), neither to citoplasmatic maturation (p=0,792). We could conclude that after nine consecutive sessions of follicle aspiration the number and quality of the recovery oocytes were constant, as well as nuclear and citoplasmatic maturation rates. Therefore, laparoscopic recovery of oocytes is a viable technique for repeated follicle aspiration in the same donor / Mestre

Laparoscopy has been shown in human medicine to have a rapid recovery time and less morbidity when compared to open abdominal surgery. It involves the insufflation of carbon dioxide into the peritoneal cavity. This creates a space for the surgeon to work in and manipulate the organs. In the normal abdominal cavity the peritoneal cavity is a potential space obliterated by the serosal contact between all the organs. The insufflation of carbon dioxide turns this potential space into a working space. This allows the introduction of an endoscope, usually through a single port, and then various instruments usually through another port into the peritoneal cavity. Multiple veterinary studies have shown the advantages of laparoscopy to decrease the morbidity of animals post surgery. The visualisation of the organs tends to be enhanced by the increased lighting and magnification provided by the laparoscopic equipment. There are intricate attachments and associations between various abdominal organs that are responsible for maintaining organ position and orientation in the peritoneal cavity. Computed tomography (CT) has been proven in human medicine to show excellent abdominal anatomical resolution. It is the modality of choice to detect free abdominal gas. Logically, if there is a massive insufflation of gas, it would be expected that this will enhance the ability of CT to provide real anatomical likeness to the laparoscopic image. The animals were all subjected to multiple CT scans and the scans were found to be rapid and noninvasive. There was a concern over the amount of radiation that each animal received and this was pre-empted by using a CARE 4D dose. The CT machine detected the thickness of the part of the animal being scanned and only provided the needed kV and mAs to penetrate and create an image. This was a paediatric human modality. Six beagle dogs were used and all assessed prior to the study to be clinically healthy. An abdominal ultrasound was performed to assess that they had normal abdominal anatomy. All animals had eight scans performed, four pre-insufflation (PrI) and four post-insufflation (PoI). The animals were placed in a ventro-dorsal routine (VDR), a ventro-dorsal Trendelenburg (VDT), a left lateral (LL) and a right lateral (RL) position. The scans were performed using a helical dual slice sliding gantry CT machine, Somatom Emotion (Siemens AG, Erlangen, Germany). With the insufflation of carbon dioxide in this study, the attachments and associations change and these were shown to play a role in the movement of the abdominal organs during the manipulations and how the organs come to lie in the abdominal cavity. It was shown that together with the insufflation of carbon dioxide into the abdomen, a very important factor in the movement of the organs was gravity. In certain organs the effect of gravity was found to be the significant factor when the positioning of the animal was changed, more so than the insufflation of the abdomen when PrI and PoI scans were compared. The effects of gravity during the changes in position and the insufflation of the abdomen were compared using a set number of measurements, of organ size and location. The size and location of the organs was compared to set landmarks in the body such as the sternum and certain vertebra, depending on the organ in question. These measurements were compared between the pre- and post-insufflation scans to evaluate the changes that occurred after insufflation with regards to the movement of certain organs and their exposure for a surgical approach. These measurements gave the data an objective value which could then be analysed statistically to determine any significant changes. The p value was set at <0.05 in determining statistical significance using a Kruskal-Wallis one way of variance (ANOVA) and the Tukey-Kramer multiple comparison test. This data was analysed and used to determine the best position to place an animal in order to perform laparoscopic surgery of certain organs. This dissertation showed that the VDR and VDT positions proved much better laparoscopic access to the majority of the parenchymatous organs in the peritoneal cavity than the lateral positions. There were certain organs such as the kidney, the ovaries, the uterine horns and the duodenum that were visualised on CT clear of the rest of the parenchymatous organ mass on the non-dependant part in the respective lateral positions. This indicated that these organs will be easily accessible during laparoscopic surgery in the RL and LL. However no matter what position was used, no position was perfect for every organ of interest, and positions need to be combined for certain procedures. The use of positioning will not remove the need for intra-operative retraction and laparoscopic retractors are an essential part of the surgeon’s arsenal when performing laparoscopic procedures. Copyright / Dissertation (MMedVet)--University of Pretoria, 2011. / Companion Animal Clinical Studies / unrestricted

This research presents the design, fabrication and controller development of a robotic retractor which driven by a robotic manipulator for laparoscopic colorectal surgery. The system consists of a dual-head fan retractor and a manipulator. The dual-head fan retractor comprises two fan devices, retractor wrist, tubular element and handle. The fan device is facilitated with a fan end-effector, an expansion mechanism and a clutchspring mechanism. Two fan devices have been used in the system to provide an anthropoid hand-holding shape which is specifically advanced for surgical purpose because intestine tends to slip when subject to disturbance and the anthropoid handholding shape can effectively halt that. One of the two fan devices is rotatable which makes the anthropoid hand-holding shape achievable. The retractor wrist possesses a triggering device, based on clutch-spring mechanism, for rotating the rotatable fan device. The clutch-spring mechanism has an impact on rotating the palms of the fan devices. In front of the handle, it is the so called front body which includes two fan devices, retractor wrist and tubular element. The front body can be controlled and is motorised using two motors fixed to the tubular element. The dual-head fan retractor is modelled in SolidWorks, and stress analysis of the retractor has been carried out by SolidWorks Simulation. Then, the mathematical model of the fan blades is developed. A 3-joint manipulator is modelled and controlled by a computed torque PD control approach as part of an investigative study to fit such a system to the retractor for robotic manipulation. Based on this investigation, the retractor is attached to a 2-joint robotic manipulator which has one rotational joint and a prismatic joint. This manipulator is mathematically modelled, and the dynamic equations are obtained. Control methods from Azenha and Khatib are simulated and compared. Azenha & Machado's method has fewer input parameters and less oscillation when utilising the same control gains. Timeoptimal control is then successfully developed for the above 2-joint manipulator. This study clearly indicates that a retractor to be used for laparoscopic surgery can be effectively controlled using a multi-joints and multi degrees of freedom robotic manipulator.

Includes bibliographical references. / 1 v. : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / A thesis based on collective clinical, basic research material and publications in endoscopic paediatric surgical procedures. Discusses the application of adult percutaneous renal surgical techniques for managing renal calculi disease in children, and modifications to this technique. Describes the introduction to laparoscopic surgery and the author's contribution to this technique. Also includes publications on paediatric urology. / Thesis (M.D.)--University of Adelaide, Dept. of Surgery, 2000

Accompanying CD-ROM contains image files and software. / Bibliography: leaves 259-286. / xvi, 286 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Explores the factors affecting the movement of tumour cells from a primary malignancy across the peritoneal cavity to the port-site following laparoscopic intervention. Filter methods and radio-labelled tumour cells provided the most useful way of following cell movement. Concludes spread of tumour cells to the port-site is more likely in the presence of disseminated disease, as well as with inappropriate surgical technique. Metastasis may be reduced by the use of intraperitoneal lavage and appropriate surgical technique. / Thesis (M.D)--University of Adelaide, Dept. of Surgery, 1999

published_or_final_version / abstract / toc / Surgery / Master / Master of Surgery

Thesis (M.S.)--University of Hong Kong, 2002. / Title from title frame. Includes bibliographical references (leaves 133-151).

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed May 16, 2007). PDF text: x, 248 p. : ill. (some col.) ; 4.25Mb. UMI publication number: AAT 3237054. Includes bibliographical references. Also available in microfilm and microfiche formats.