In this article, a new Micromanipulator System (MMS-II) for middle ear surgery is presented. The purpose of this work was to develop a simple but effective manipulator that would enable the surgeon to move standard surgical instruments in a precise way even under non-ergonomic conditions. The MMS-II is lightweight, small, and easy to use; it requires no PC, besides a small microcontroller-based joystick console. Such features, together with a practicable sterilization concept and the availability of a multiplicity of surgical instruments, allow the system to be used in standard surgical procedures.

OBJECTIVE: Surgical Process Models (SPMs) are models of surgical interventions. The objectives of this study are to validate acquisition methods for Surgical Process Models and to assess the performance of different observer populations. DESIGN: The study examined 180 SPM of simulated Functional Endoscopic Sinus Surgeries (FESS), recorded with observation software. About 150,000 single measurements in total were analyzed. MEASUREMENTS: Validation metrics were used for assessing the granularity, content accuracy, and temporal accuracy of structures of SPMs. RESULTS: Differences between live observations and video observations are not statistically significant. Observations performed by subjects with medical backgrounds gave better results than observations performed by subjects with technical backgrounds. Granularity was reconstructed correctly by 90%, content by 91%, and the mean temporal accuracy was 1.8 s. CONCLUSION: The study shows the validity of video as well as live observations for modeling Surgical Process Models. For routine use, the authors recommend live observations due to their flexibility and effectiveness. If high precision is needed or the SPM parameters are altered during the study, video observations are the preferable approach.

Abstract We present a full featured surgery simulator for endoscopic third ventriculostomy (ETV) in an interactive grid environment. The basic ventriculostomy simulator introduced previously has been extended with new 3D models and animation methods for raising the simulation realism. It enables full haptic interaction with textured deformable models of a hydrocephalic configured human ventricular system derived from MR‐data. Visual effects like bleeding in the cerebrospinal fluid (CSF) have been implemented for faulty interactions during training sessions which are recorded in a database for further evaluation. Based on the training data comparative studies were carried out whereas the benefits of virtual reality (VR)‐based training have been demonstrated. Furthermore, KisGrid is presented as an interactive grid environment for real‐time surgical simulators. It enables collaborative and supervised haptic training over networks with access to remote surgical models and hardware. The grid applet ViCoM is introduced as a tool for audio‐visual communication, monitoring, and training session archiving. Long distance tests have been successfully carried out for multicast video conferencing, training session monitoring, and haptic surgical collaboration with deformable models. Copyright © 2009 John Wiley & Sons, Ltd.

For difficult cases in endoscopic sinus surgery, a careful planning of the intervention is necessary. Due to the reduced field of view during the intervention, the surgeons have less information about the surrounding structures in the working area compared to open surgery. Virtual endoscopy enables the visualization of the operating field and additional information, such as risk structures (e.g., optical nerve and skull base) and target structures to be removed (e.g., mucosal swelling). The Sinus Endoscopy system provides the functional range of a virtual endoscopic system with special focus on a realistic representation. Furthermore, by using direct volume rendering, we avoid time-consuming segmentation steps for the use of individual patient datasets. However, the image quality of the endoscopic view can be adjusted in a way that a standard computer with a modern standard graphics card achieves interactive frame rates with low CPU utilization. Thereby, characteristics of the endoscopic view are systematically used for the optimization of the volume rendering speed. The system design was based on a careful analysis of the endoscopic sinus surgery and the resulting needs for computer support. As a small standalone application it can be instantly used for surgical planning and patient education. First results of a clinical evaluation with ENT surgeons were employed to fine-tune the user interface, in particular to reduce the number of controls by using appropriate default values wherever possible. The system was used for preoperative planning in 102 cases, provides useful information for intervention planning (e.g., anatomic variations of the Rec. Frontalis), and closely resembles the intraoperative situation.

Slice-based visualizations of CT and MRI data are frequently used for diagnosis, intervention planning and intraoperative navigation since they allow a precise analysis and localization. We present new techniques to enhance the visualization of cross sectional medical image data. Our work is focussed on intervention planning and intraoperative navigation. We address the following problems of slice-based visualization in these areas: the lack of a graphical overview on the positions of anatomic structures, the localization of a target structure and the display of safety zones around pathologic structures. To improve the overview, we introduce LIFTCHARTs, attached as vertical bars to a slice-based visualization. For localizing target structures, we introduce halos. These techniques restrict the occlusion of the original data to a minimum and avoid any modification of the original data. To demonstrate the usability of these visualization techniques, we show two application scenarios in which the techniques come into operation.

In this paper, we present visualization techniques for neck dissection planning. These interventions are carried out to remove lymph node metastasis in the neck region. 3d visualization is intended to explore and to quantify anatomic and pathologic structures and thus support decisions concerning the surgical strategy. For this purpose we developed and combined visualization and interaction techniques such as cutaway views, silhouettes and colorcoded distances. In addition, a standardized procedure for processing and visualization of the patient data is presented.