Combined external-endonasal approach for complete excision of the lacrimal drainage apparatus

Purpose: The purpose of this study was to describe a new surgical technique for the complete excision of the lacrimal drainage apparatus (LDA) that combines external and endoscopic approaches. Methods: This study involved a noncomparative, retrospective chart review of the clinical and pathological findings of four patients presenting with LDA papillomas who underwent a combined open and endonasal excision of the lacrimal system. Results. Of the four patients, three were male. The mean age at referral was 41 years, and all cases were unilateral. Histopathology revealed two transitional cell papillomas, one squamous cell papilloma, and one combined transitional/squamous papilloma. Epiphora and an external lesion were the main complaints at presentation. Nasolacrimal duct obstruction was present in all four patients. Papilloma virus infection was suggested in two cases and was confirmed in the only patient who had recurrence. CT identified a solid enhancing mass in two cases. The surgical approach in all cases was performed with the patient under general anesthetic supplemented with infiltration of local anesthesia with vasoconstriction. The lacrimal sac was exposed as per an external dacryocystorhinostomy with biopsy collection from the lacrimal sac lumen to confirm the diagnosis prior LDA excision. The superior aspect of the LDA was isolated by using lacrimal probes in each canaliculus to stabilized parallel incisions and careful dissection toward the common canaliculus until they met the medial aspect of the lacrimal sac. The sac was then separated from the periosteum from the medial orbital wall, using sharp dissection. Finally, an endoscopic dissection of the lower end of the nasolacrimal duct released the most inferior aspect of the LDA, allowing the surgeon to pull and excise the complete system from the external wound. Conclusions: Extensive LDA papillomas required complete excision of the drainage system to prevent recurrence and/or malignant transformation. The use of a combined approach through an open excision of the superior part of the LDA in conjunction with the direct manipulation of the nasolacrimal duct guided by the nasal endoscope facilitates the complete excision of the system for extensive benign lesions.

Listening to the 'voices' of students with severe learning difficulties through a task-based approach to research and learning in physical education

In this article, Hayley Fitzgerald, Anne Jobling and David Kirk consider the physical education and sporting experiences of a group of students with severe learning difficulties. Their study is thought provoking, not only because of the important and somewhat neglected subject matter, but equally for the research approach adopted. The way in which the study engaged with the students and the insights gained from that engagement will be of particular interest to practitioner researchers.

Laparoscopic Swenson procedure - An optimal approach for both primary and secondary pull-through for Hirschsprung's disease

Background/Purpose: Several pull-through procedures are available for the surgical management of Hirschsprung's disease (HD) in children. The authors have adopted a laparoscopic approach since 1995, including laparoscopic Swenson procedure (LSw), both for one-stage primary and 2-stage secondary procedures. The aim of this study was to examine the role of LSw in children with HD in both primary and secondary procedures. Methods: From January 1995 to December 2001, 42 children with biopsy-proven HD underwent laparoscopic pull-through procedure for HD. This group included 29 children who underwent LSw, a detailed analysis of which forms the basis of this report. Results: Sixteen children underwent a single-stage neonatal LSw; the median weight of this group at the time of surgery was 3.2 kg and the median age was 5 days. Secondary LSw was performed in the remaining 13 children, which included 3 children with total colonic HD who underwent laparoscopic total colectomy and LSw. The median operating time was 105 minutes (range, 66 to 175 minutes). The median time to commence full diet was 48 hours (range, 24 to 86 hours), and median time to return to normal play and activity was 72 hours (range, 48 hours to 5 days). There was no difference in operating time between primary and secondary pull-through procedures. There were no intraoperative complications, and no patient required open conversion. Postoperative ileus was noted in 3 children and enterocolitis in 2. The median hospital stay was 4 days (range, 2 to 6 days). Follow-up was between 6 months to 7 years with a median follow-up of 2.2 years. At follow-up, 2 children required laparoscopic antegrade continence enema procedure. A satisfactory continence was noted in 15 of the 19 children who were older than 3 years at the time of last follow-up. Conclusions: LSw seems to be a suitable procedure for laparoscopic management of HD in children. LSw is safe and effective, both for primary and secondary type of pull-through procedures, with good short-term results.

Stochastic dynamic programming for election timing: A game theory approach

In this paper, we consider dynamic programming for the election timing in the majoritarian parliamentary system such as in Australia, where the government has a constitutional right to call an early election. This right can give the government an advantage to remain in power for as long as possible by calling an election, when its popularity is high. On the other hand, the opposition's natural objective is to gain power, and it will apply controls termed as "boosts" to reduce the chance of the government being re-elected by introducing policy and economic responses. In this paper, we explore equilibrium solutions to the government, and the opposition strategies in a political game using stochastic dynamic programming. Results are given in terms of the expected remaining life in power, call and boost probabilities at each time at any level of popularity.

Small firm internationalisation; understanding the practice through an interpretive approach

The unit of analysis in firm internationalisation studies is the firm but this overlooks the importance of the individual in the internationalisation process. An evaluation of the dominant theories of firm internationalisation highlights an implicit dualistic ontology, that is, where research subject and object are considered to be separate and independent. Implications of this assumption are discussed after reviewing the dominant literatures on firm internationalisation. An alternative approach is proposed that focuses on understanding internationalisation of the firm from an individual practitioner’s perspective. It is suggested that contemporary firm internationalisation research has been hindered by its basic assumptions and its inherent researcher orientation. An interpretive phenomenographic approach is proposed as a means of achieving a first-person, practitioner’s perspective of the process of firm internationalisation, specifically in the context of the small firm. Preliminary interpretations of interviews with owners/managers of small Australian wineries are presented.

Learning to play Pac-Man: An evolutionary, rule-based approach

Pac-Man is a well-known, real-time computer game that provides an interesting platform for research. We describe an initial approach to developing an artificial agent that replaces the human to play a simplified version of Pac-Man. The agent is specified as a simple finite state machine and ruleset. with parameters that control the probability of movement by the agent given the constraints of the maze at some instant of time. In contrast to previous approaches, the agent represents a dynamic strategy for playing Pac-Man, rather than a pre-programmed maze-solving method. The agent adaptively "learns" through the application of population-based incremental learning (PBIL) to adjust the agents' parameters. Experimental results are presented that give insight into some of the complexities of the game, as well as highlighting the limitations and difficulties of the representation of the agent.