Thesis (M.S.) -- University of Adelaide, Dept. of Surgery, 2000. / Includes bibliographical references (13 leaves).

Thesis (M.S.)--University of Michigan, 1985.

Thesis (M.S.)--University of Michigan, 1985.

Fibrotic diseases account for an estimated 45% of the total number of deaths in the developed world (Wynn 2007). Tendons are an excellent model for studying the dysregulated response which leads to fibrosis, as tendons have an organized, parallel matrix, in which tissue defects could easily be distinguished. Wong et al. (2006b) demonstrated the presence of a bell-shaped region around sutures in tendons that was devoid of cells in histological sections. The mechanisms of the formation of this acellular zone, that was also noted in cornea and cartilage (Matsuda et al. 1999; Hunziker and Stähli 2008), were unknown. It was hypothesized that the acellular zone was formed by cell death and that suturing caused alterations to the extracellular matrix of sutured regions of tendon, which made the acellular zone refractory to cellular re-population. The acellular zone was tracked in sutured tendons for up to a year to determine the temporal properties of the acellular zone. Electron microscopic and time lapse studies were carried out to determine if the acellular zone formed by cell migration or cell death. Microarray analysis was conduced to confirm this and to reveal potential molecular targets for future studies. The extracellular matrix of sutured tendons was studied by electron, atomic, scanning and polarized light microscopy and mechanical measurements were obtained using nanoindentation. It was concluded that the acellular zone formed within 24 hours and persisted for up to a year. Tension and size of the suture's grasp were also shown to be important for acellular zone formation. Cell death was the main effector of acellular zone formation. Microarray analysis showed evidence of upregulation of inflammatory mediators and programmed necrosis pathways. The sutured extracellular matrix was denser, more disorganized and had a lower Young's modulus than unsutured regions of the same tendon. These differences in the properties of the extracellular matrix of sutured tendons may be the cause of the persistence of the acellular zone.

No description available.

A live animal model of major haemorrhage using an implanted short gastric artery was devised to test the efficacy and safety of these endo-suture devices in vivo. Pulsatile arterial bleeding was successfully reproduced in eight pigs' stomachs through incision of the pre-buried vessels. Endoscopic suturing controlled the bleeding in all animals without obvious complications. The mean operating time with the Eagle Claw V was statistically shorter than that with the Eagle Claw II machine (3.6 verse 13.8 minutes, p<0.001). / A vessel-perfusion-manometry system was first established incorporating porcine stomach and splenic artery with the Erlangen model. / From these investigations, it is concluded that (1) Both the vessel-perfusion-manometry system and the animal arterial haemorrhage model are reliable, reproducible and realistic methods suitable for endoscopic experiment in the laboratory settings. (2) Either three-throw knot tied endoscopically or intracorporeal endo-loop ligation can secure vessels as large as 2mm in diameter enduring flow pressure greater than 200 mmHg. (3) It is possible to control massive arterial bleeding in stomach with endoscopic suturing using the novel apparatus with a curved needle. (4) The Eagle Claw V represents significant improvement over previous version, and is associated with ease of operation and higher security, which brings the technique closer to clinical applications. (Abstract shortened by UMI.) / Peptic ulcer remains the most common cause of upper gastrointestinal haemorrhage. Existing endoscopic haemostatic modalities cannot securely control massive ulcer bleeding from large eroded vessels. A well-designed endoscopic suturing device has the possibility to plicate large artery. In addition, it may provide enormous potential in other forms of endo-surgery. A novel suturing device using a curved needle, the Eagle Claw, was developed. The aims of this thesis were to evaluate the efficacy and safety of the Eagle Claw II and V in arresting artificial gastric bleeding from large vessel in a laboratory setting. These devices were tested both in vitro on the bench and in vivo in live animal models. / Hu Bing. / "August 2005." / Adviser: Ng Ekw. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3694. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 136-160). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

SAMMANFATTNING Bakgrund: Globalt sett drabbas cirka 70-80 procent av alla kvinnor av någon typ av bristning i underlivet när de föder sitt första barn och dessa skador kan orsaka både smärta och lidande. Det är av stor vikt att barnmorskor och obstetriker känner till det kvinnliga könsorganets anatomi så att både diagnostisering och handläggning av bristningar blir korrekt. Forskning kring hur dessa skador skall kunna undvikas är ständigt pågående. En av de många frågor som ställs är huruvida förekomsten av dessa skador minskar när barnmorskan utför perinealskydd och hur detta används när kvinnan föder i vatten. Vattenfödsel är ett omdiskuterat ämne och forskare har olika uppfattning om dess för- och nackdelar. Syfte: Syftet med detta arbete var att beskriva utfallet och handläggningen av perinealbristningar vid vattenfödslar. Metod: En kvantitativ ansats har använts och information ifrån 123 kvinnors förlossningsjournaler har sammanställts. Alla kvinnorna födde sina barn i vatten på BB Sophia eller Södra BB från mars 2014 till mars 2015. Bristningsgrad har beskrivits i tabeller och diagram i förhållande till variablerna paritet, barnets vikt, utdrivningsskedets längd, barnets huvudomfång, tid för bad, BMI, ålder och suturering. Resultat: Betydligt fler av förstföderskorna drabbades av perinealbristning än vad omföderskorna gjorde. Av de kvinnor som fick en grad 3 eller grad 4 bristning hade alla längre utdrivningsskeden och var förstföderskor. Nio procent av kvinnorna i studien fick en grad 3 bristning vilket ses som en hög siffra. Av de totalt 101 kvinnorna som fick någon typ av perinealbristning lämnades tio stycken osuturerade och nästan hälften av barnmorskorna som besvarat enkäten använde sig av perinealskydd vid vattenfödslar. Slutsats: Att vara förstföderska ökar risken för perinealbristningar oavsett om kvinnan föder i vatten eller inte. Utdrivningsskedets längd kan ha betydelse samt även om barnmorskan använder perinealskydd eller inte. Vad som i övrigt påverkar utfallet av bristningar vid vattenfödsel är inte säkerställt. Mer forskning i ämnet behövs.

Thesis (MMed)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: OBJECTIVE The purpose of the study is to establish the best method of wound closure with regards to patient satisfaction that includes wound cosmesis and pain. STUDY DESIGN One hundred patients were randomised to two groups for the closure of abdominal wounds; one group had subcuticular sutures and the other staples. They were followed up at 6 weeks. The primary outcome was patient satisfaction that includes wound cosmesis and pain. The secondary outcome was wound complications. RESULTS In women undergoing abdominal operations there was no difference as regards the patient satisfaction in both the groups, subcuticular sutures n= 51 vs. staples n=49 (P = 0.76). CONCLUSION Our study suggest that there is no statistically significant difference in the methods of wound closure, subcuticular sutures vs. staples as regards the patient satisfaction and the appearance of the scar leaving the decision in the hands of the surgeon to choose any method according to their own personnel preference and availability. / AFRIKAANSE OPSOMMING: NAVORSINGSDOEL Die fokus van hierdie projek is om vas te stel wat die beste metode van vel sluiting is ten opsigte van pasiënt bevrediging ten opsigte van wond voorkoms en pyn. METODES Een honderd pasiënte is ewekansig verdeel tot velsluiting van abdominale wonde met subkutane oplosbare steke of velhakies. Evaluasie is gedoen tydens ‘n opvolg besoek 6 weke na chirurgie. Die hoof uitkoms was pasiënt tevredenheid. Evaluasie van wond komplikasies is as sekondêre uitkoms beskryf. RESULTATE Vroulike pasiënte wat ‘n Pfannenstiel velinsnyding ondergaan toon geen verskil in pasiënt tevredenheid wanneer subkutane steke (n = 51) met velhakies (n = 49) vergelyk word nie (P = 0.76). SAMEVATTING Ons projek het geen statisties beduidende verskil getoon ten opsigte van pasiënt tevredenheid of wond voorkoms met 6 weke opvolg nie. Dit laat dus die besluit by die chirurg om metode van velsluiting te kies afhangend van voorkeur en toerusting beskikbaarheid.

Minimally invasive or laparoscopic surgery has completely changed the focus of surgery becoming an alternative to various types of open surgery. Minimally invasive surgery avoids invasive open surgery as the operation is performed through one or more small incisions in the abdomen and using a small camera called laparoscope. Through these incisions, surgeons insert specialized surgical instruments to perform the operation resulting in less postoperative pain, shorter hospital stay, and faster recovery. However, the main problems during minimally-invasive surgery are the limited space for operating instruments and the reduced visibility and range of motion inside the patient’s body. During minimally-invasive surgery, one of the most difficult and time consuming surgical procedures is suturing and knot tying. This procedure significantly increases the operation time as it requires advanced techniques and extensive experience by surgeons.The main goal of this research is to investigate, design, and develop a new suturing instrument to facilitate suturing procedures during minimally invasive surgery.Qualitative research data was collected through interviews with a surgeon and six indepth observations of minimally invasive surgeries at Tampa General Hospital. Different design concepts and mechanisms were created using SolidWorks CAD software, and tested using SimulationXpress in order to identify dimensions, materials and expected performance of the design and its components. The prototypes of the device were made using a Dimension SST 768 FDM machine and tested by the surgeon to ensure that the final design meets the specified needs and criteria. This new device will eliminate the use of many different devices during the operation and allow the use of any type of suture. The proposed suturing device aims to benefit both patients and surgeons. For surgeons, the new device aims to decrease the number of steps for laparoscopic suturing through an intuitive and ergonomic design. For patients, the proposed device will reduce time during surgery and under general anesthesia leading towards improved health care.

Successful applications of Reinforcement Learning (RL) in the robotics field has proliferated after DeepMind and OpenAI showed the ability of RL techniques to develop intelligent robotic systems that could learn to perform complex tasks. Ever since the use of robots for surgical procedures, researchers have been trying to bring some sort of autonomy into the operating room. Surgical robotic systems such as da Vinci currently provide the surgeons with direct control. To relieve the stress and the burden on the surgeon using the da Vinci robot, semi-automating or automating surgical tasks such as suturing can be beneficial. This work presents a RL-based approach to automate the needle hand-off task. It puts forward two approaches based on the type of environment, a discrete and continuous space approach. For capturing a unique suturing style, user data was collected using the da Vinci Research Kit to generate a sparse reward function. It was used to derive an optimal policy using Q-learning for a discretized environment. Further, a RL framework for da Vinci Research Kit was developed using a real-time dynamics simulator - Asynchronous Multi-Body Framework (AMBF). A model was trained and evaluated to reach the desired goal using model-free RL techniques while considering the dynamics of the robot to help mitigate the difficulty in transferring trained model to real-world robots. Therefore, the developed RL framework would enable the RL community to train surgical robots using state of the art RL techniques and transfer it to real-world robots with minimal effort. Based on the results obtained, the viability of applying RL techniques to develop a supervised level of autonomy for performing surgical tasks is discussed. To summarize, this work mainly focuses on using RL to automate the suture hand-off task in order to move a step towards solving the greater problem of automating suturing.