Infected nasal gout tophus: A case report.

Gout is a common form of inflammatory arthritis, characterized by the deposition of monosodium urate crystals. If chronically present and not adequately treated by serum urate reducers, gout tophi can develop at various locations. Here, we report the first infected gout tophus at the septal cartilage and nasal tip.

[Development and evaluation of a simulator for endoscopic sinus surgery]. / Entwicklung und Evaluation eines Simulators für die endoskopische Nasennebenhöhlenoperation.

BACKGROUND: Endoscopic surgical procedures have been established as gold standard in sinus surgery. Challenges for surgical training have been addressed by the use of virtual reality (VR) simulators. To date, a number of simulators have been developed. However, previous studies regarding their training effects investigated only medically pretrained subjects or the time course of training outcomes has not been reported. METHODS: A computer tomography (CT) dataset was segmented manually. A three-dimensional polygonal surface model was generated and textured using original photographic material. Interaction with the virtual environment was performed using a haptic input device. For the investigation of training outcomes with the simulator, the parameters duration and the number of errors were recorded. Ten subjects completed a training consisting of five runs on ten consecutive days. RESULTS: Within the whole exercise period, four subjects reduced the duration of intervention by more than 60%. Four subjects reduced the number of errors by more than 60%. Eight out of 10 subjects showed an improvement with respect to both parameters. On median, the duration of the procedure was reduced by 46 seconds and the number of errors by 191. The statistical analysis between the two parameters showed a positive correlation. CONCLUSION: Our data suggests that training on the FESS-simulator considerably improves the performance even in inexperienced subjects, both in terms of duration and accuracy of the procedure.

[ElePhant: an anatomic-electronic simulation system for the evaluation of computer assisted interventions and surgical education]. / ElePhant: ein anatomisch-elektronisches Simulationssystem für die Evaluation computerassistierter Eingriffe und die chirurgische Ausbildung.

BACKGROUND: Suitable simulation systems providing realistic conditions are required for preclinical evaluation of computer assisted interventions and surgical training. Techniques are necessary for an objective detection of injuries to the structures at risk. The aim of this study was the technical realization of a simulation system for the ENT intervention, mastoidectomy. MATERIALS AND METHODS: The basis of the simulation system was a CT scan of a cadaver skull. Using 3D printing, an anatomical phantom with realistic bone-like properties was created. Electronic detection systems were integrated into the structures at risk. A study with 16 ENT surgeons was conducted to prove the system's suitability for surgical training. RESULTS: The creation of simulation systems for the objective evaluation of surgical intervention qualities is feasible. A modular structure enables economic and simple replacement of the simulation area. The modules are cost effective and reproducible with high accuracy. The present study shows that the simulation system can be applied in surgical education and evaluation as an alternative to cadavers. CONCLUSION: Objective evaluation of injured structures at risk can be realized in real time. The simulation system permits preclinical evaluation studies of computer assisted instruments and surgical education. Reproducibility of the results makes multi-center studies possible.

Requirement specification for surgical simulation systems with surgical workflows.

Surgical simulations are normally developed in a cycle of continuous refinement. This leads to high costs in simulator design and as a result to a very limited number of simulators which are used in clinical training scenarios. We propose using Surgical Workflow Analysis for a goal-oriented specification of surgical simulators. Based on Surgical Workflows, the needed interaction scenarios and properties of a simulator can be derived easily. It is also possible to compare an existing simulator with the real workflow to distinguish whether it behaves realistically. We are currently using this method for the design of a new simulator for transnasal neurosurgery with good success.