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In der Fachliteratur und den Fachgesellschaften existieren keine verbindlichen didaktischen Empfehlungen bzw. Richtlinien zur Gestaltung chirurgischer Trainingskurse. Die fortbildenden Institutionen planen, organisieren und evaluieren in Eigeninitiative ihre Bildungsprogramme und -veranstaltungen. In den Kursen eines Bildungsanbieters wurden im Rahmen eines Forschungsprojekts mit einer padagogisch-wissenschaftlich arbeitenden Forschergruppe strukturierte Beobachtungen, Expertendiskussionen mit Kursverantwortlichen und Trainern sowie Auswertungen von Teilnehmerfragebogen durchgefuhrt. Erste Masnahmen wurden installiert und umgehend in den Prozess der fortlaufenden Evaluation einbezogen. Aus der Evaluation ergaben sich konkrete Veranderungen im organisatorischen und mikrodidaktischen Bereich, die schnellstmoglich eingebunden wurden. Des Weiteren ergaben sich langerfristig zu bearbeitende Aufgaben in den Bereichen (a) Rollenverstandnis des Trainers, (b) Feedback geben respektive Leistung bewerten und (c) Inhalte differenziert aufbereiten. Fur Fortbildungsveranstalter in der Medizin ist eine langerfristige Zusammenarbeit mit einer begleitenden padagogisch tatigen Institution nicht nur moglich sondern empfehlenswert.

Diese Arbeit stellt ein neuartiges Trainingskonzept fur die Felsenbeinchirurgie auf der Basis von Gips-Kunstoff-Modellen mit optoelektrischer Detektion von Risikostrukturen vor und evaluiert es prototypisch. Grundlage der Trainingsmodelle sind hochauflosende CT-Datensatze eines humanen Schadels. Der Datensatz wird an einem 3D-Drucker ausgedruckt. Aus Gipspulver und einem Bindemittel wird das dreidimensionale Phantom erstellt. Als Risikostrukturen wurden der N. facialis, der Labyrinthblock, die Ossikelkette, der Sinus sigmoideus, die Dura und die A. carotis interna definiert. Als Detektionsmaterialien fur die Risikostrukturen werden eine elektrisch leitfahige Metalllegierung und ein Lichtwellenleiter verwendet. 8 unerfahrene und 8 efahrene Ohrchirurgen trainierten an den optoelektrischen Trainingssystemen (Gruppe A) und auserdem an humanen Felsenbeinpraparaten (Gruppe B). Bei Verletzungen werden Anzahl, Zeitpunkt, Grad (N. facialis) und verletzte Struktur, auserdem die benotigte Gesamtzeit werden wahrend des Trainings am Modell protokolliert. Die Auswertung der anatomischen Detailtreue der Felsenbeinmodelle zeigte Ergebnisse zwischen 49,5% und 90% Ubereinstimmung. Die Fehlerdetektion wurde mit Werten zwischen 79% und 100% Ubereinstimmung mit der Wahrnehmung eines erfahrenen Chirurgen bewertet. Das Op.-Setting wurde besser gegenuber dem Frasen am humanen Felsenbeinpraparat eingeschatzt. Die Probanden bejahten die Moglichkeit, die bisherige Trainingsmethode am humanen Felsenbeinpraparat vollstandig durch das Training am untersuchten Modell zu ersetzen. Die vorliegenden Daten belegen die Eignung des hier untersuchten neuartigen Trainingssystems fur die Felsenbeinchirurgie. Das System verbindet die Vorarbeiten mit gedruckten und gesinterten Modellen mit den Moglichkeiten der Mikrosystemtechnik. Daruber hinaus ist eine vollstandige virtuelle Darstellung des Modells mit den entsprechenden weiterfuhrenden Anwendungen („look behind the wall“, virtuelle Endoskopie) moglich.

Hintergrund Die „Funktionelle Endoskopische Nasennebenhohlenoperation“ (FESS) ist durch eine einhandige Praparation und die Fuhrung des Endoskops mit der nichtdominanten Hand gekennzeichnet. Daraus ergeben sich eine Verlangerung der Operationszeit von bis zu 15% und ergonomische Defizite fur den Chirurgen. Das Ziel der vorliegenden Arbeit ist die Fortfuhrung der Konzeption eines automatisierten Assistenzsystems fur die Endoskopfuhrung bei der FESS. Dabei stehen folgende Fragen im Mittelpunkt: 1. Welches Design ist fur eine teilautomatisierte Endoskopfuhrung bei der FESS geeignet? 2. Wie sind die technischen Systemeigenschaften (Planung, Zeitaufwand, Genauigkeit, Prazision) des gewahlten Systems? 3. Bietet das System Potenzial fur eine klinische Anwendung?

Background The aim of this study was to evaluate the Navibase navigation system for ear, nose, and throat (ENT) surgery. A new methodology for evaluating surgical and human factors is developed. Patients and methods The evaluation is based on 102 ENT surgical applications, including 89 cases of functional endoscopic sinus surgery (FESS). The evaluation of surgical and human factors was performed by seven ENT surgeons. To evaluate surgical performance, level of quality (LOQ) in the 89 cases of FESS was determined, comparing the surgeon's own impressions with those of the navigation system on a scale from 0 to 100 and further comparing them with clinical results. Intraoperative changes in surgical strategy were documented. The human factors of total confidence (trust), situation awareness, skill set requirement and workload shift were recorded as level of reliance (LOR). Results The maximum deviation amounted to 1.93 mm. Averaging the quality of information resulted in an LOQ of 63.59. Every second application of the navigation system (47.9%) led to a change in surgical strategy. Total confidence showed a positive evaluation of 3.35 points in LOR. Conclusion Application-relevant information relevant to the application beyond only technical details permits comparison with other assisting systems.

Background: The feasibility of a navigate-controlled Shaver for the paranasal sinus surgery was proven in an initial study. Deficits showed up in the conversion of the planed cavity. Goal of this study is (1) the development and evaluation of a FESS demonstrator for the investigations to the surgical accuracy and (2) the evaluation of the resulting surgical accuracy for registration and conversion of the work space with an improved rigidity of the Shaver and a completely revised study design. Methods: As a demonstrator for the navigate-controlled resection of a volume through the Shaver a two-piece plastic head with an anatomical head and soft tissue model was designed. The investigation of the surgical accuracy takes place with 417 measurements to 4 different fiducial markers on the demonstrator head. The measurements for the deviation of the resulting cavity from the planned volume was realised with a work space by 24 x 24 × 30 mm. The 5 walls of the cavity were seized with 80 measuring points for each level and thus altogether 2000 measured values (5 models × 5 levels × 200 points). Results: The described demonstrator showed itself suitable for the close-to-application attempts to the surgical accuracy. The maximum deviation A max indicated position of the Shaver from the reference value amounted to 1,93 mm. The maximum average value of the exceeding of a planned cavity amounts to 1,62 mm. Conclusions: Based on these results a virtual safety passage of 2.00 mm is sufficient. The study refers the clinical serviceability of the navigate-controlled Shaver in paranasal sinus surgery.

Die Genauigkeit von Navigationssystemen stellt das herausragende Kriterium fur die Evaluation von Navigationssystemen dar. Die Angaben zur Genauigkeit variieren erheblich, und es besteht eine Diskrepanz zwischen Literaturangaben und der intraoperativen Genauigkeit. Es existiert kein einheitliches Verstandnis fur die Begriffe Genauigkeit und Prazision von Navigationssystemen, falschlicherweise werden diese auch gleichbedeutend verwendet. Daruber hinaus ist die klinische Genauigkeit nicht mit der technischen Bestimmung gleichzusetzen. Die vorliegende Arbeit hat das Ziel, den Begriff Genauigkeit und verwandte Begriffe grundlegend zu definieren, den Begriff der Prazision abzugrenzen, den Begriff chirurgische Genauigkeit abzuleiten, einen Vorschlag fur die Anwendung des Begriffs der chirurgischen Genauigkeit eines Navigationssystems zu unterbreiten, die vorhandenen Literaturangaben entsprechend einzuordnen. Dafur kamen die Normen nach der International Standardisation Organisation-ISO und dem Deutschen Institut fur Normung e.V.-DIN zur Anwendung.

In the Special Research Centre 414 of the German Research Funding (DFG, Bonn) a system for robot-assisted cranial surgery was developed. It is designed for the accurate and safe execution of craniotomies and repositioning of bone pieces. The system is intended for use in the surgical therapy of craniosynostosis. Preoperatively, CT imaging is performed. In a computerized planning system the position and shape of the intended craniotomy is intuitively planned on a virtual model of the patient's skull. Intraoperatively, after conventional removal of the covering soft tissue, the robot performs the craniotomy autonomously. Extensive testing in phantom studies and animal tests confirmed the reliability and accuracy of the system. A thorough risk analysis of the system was performed. In this paper, the first clinical use of the system on a patient is described and the clinical importance is discussed.

The use of surgical robots and manipulators is still being frequently discussed in the mass media as well as in the scientific community. Although it was already noted in 1985 that the first patient was treated by a joint team of robot and surgeon, today such systems are not routinely used. This can be explained by the high complexity of such systems and the often limited usability, but also, that it is difficult for surgeons to accept "automatic" machines. In this paper the possibilities and chances of robots and manipulators will be explained and it will be shown that robots will never work alone in the operating theatre as it is common in industry today. On the other hand, also limitations and challenges will be outlined. Therefore first a review on today's systems is given in different disciplines including oral- and cranio-maxillofacial surgery, then advantages and disadvantages are shown.

Current advise systems in surgery use standard colors to communicate specific messages. Unfortunately, these colors may have a poor contrast to the background, like red on blood rich backgrounds of an OR microscope intervention. In this work, we present an approach of choosing high contrast colors based on the current image content, which is used in a study for an AR-based mode display of an active computer assisted surgery system.

In this paper, part of the invited session - Automation in medicine, the different effects of automation to the surgeon are discussed, including positive and negative consequences. One approach to analyze effects of automation is explained, and exemplarily shown on a study of the mode error at the computer assisted surgery (CAS) system navigated control.

The aim of this work was the evaluation of a navigated and power controlled milling system for spine surgery (navigated control spine). The navigation is based on a set of intraoperatively taken fluoroscopic images from different angles. A manually planned workspace limits the power of the mill and assures a higher automatisation degree than any other established navigation system for spine surgery.Both a technical study in workspace planning from fluoroscopic images and a milling study on a spine phantom were performed with participants with different level of knowledge of spinal surgery.In the region of interest the workspace planning could be performed with a maximum excess of 1.40 mm for surgeons. In the study performing the milling of a standardised workspace the remnant bone after milling had a mean difference from the planned workspace margin of 1.96-2.12 mm in the region of most interest. Accurate handling of the mill still required a certain level of medical knowledge and experience. In both studies the time needed for application of the system proved acceptable for clinical purposes.This concept of navigated and power controlled spinal surgery has proven feasible in an experimental study. This navigation system seems therefore promising for clinical application.

The aim of this study is the evaluation of a navigation system (NaviBase) for ENT surgery. For this purpose, a new methodology for the evaluation of surgical and ergonomic system properties has been developed. The practicability of the evaluation instruments will be examined using the example of the overall assessment of the system in comparison with the current surgical standard and with other systems using clinical efficiency criteria. The evaluation is based on 102 ENT surgical applications; of these, 89 were functional endoscopic sinus surgeries (FESS). The evaluation of surgical and ergonomic performance factors was performed by seven ENT surgeons. To evaluate surgical system properties, the Level of Quality (LOQ) in 89 cases of the FESS was determined. It compares the existing information of the surgeon with that of the navigation system on a scale of 0 to 100 and with a mean value of 50 and places it in a relationship to the clinical impact. The intraoperative change of the planned surgical strategy (Change of Surgical Strategy) was documented. The ergonomic factors of the system with the categories of Overall Confidence (Trust), awareness of the situation (Situation Awareness), influence on the operating team, requirements for specific skills (Skill Set Requirement), and cognitive load (Workload Shift) were recorded for all surgical procedures as Level of Reliance (LOR). In the evaluation of the surgical system properties, an average evaluation of the quality of the information, as an LOQ of 63.59, resulted. Every second application of the navigation system (47.9%), on average, led to a change in the surgical strategy. An extension/enhancement of the indication of the endonasal approach through the use of the navigation system was shown in 7 of 102 (6.8%) cases. The completion of the resection in the FESS was rated by 74% of group I and 11% of group II as better in comparison with the standard approach. Total confidence shows a positive evaluation of 3.35 in the LOR. To supplement the evaluation of the navigation system, the technical parameters were included. The maximum deviation, Amax, of the displayed position of the reference value amounted to 1.93 mm. The average deviation was at 1.29 mm with an SD above all values, sd, of 0.29. The subsequent economic evaluation resulted in an effective average extra expenditure of time of 1.35 minutes per case. The overall evaluation of the system imparts application-relevant information beyond the technical details and permits comparability between different assistance systems.