Biomedical subjects

V Sørhus

Publications and source records attributed to V Sørhus.

3 recordsLinked to original sources

PubMed2006

Virtual reality simulator training equals mechanical robotic training in improving robot-assisted basic suturing skills.

BACKGROUND: This study aimed to investigate the effect of a virtual reality simulator on the learning of basic robotic suturing skills. METHODS: Two randomized groups of students underwent a controlled training program. Both groups completed an identical test before and after training. The increase in the number of stitches placed during the pretest and posttest was used as an objective measure of the training effect. To evaluate the subjective feeling of understanding and mastering, the students indicated this on a visual analog scale. RESULTS: Both groups showed a significant increase in the number of stitches placed during the posttest, and an increase in subjective feeling of understanding and mastering. The increase did not differ between the groups, indicating that the virtual reality simulator equaled the mechanical trainer in training of robotic suturing technique. CONCLUSIONS: Training in basic robot-assisted suturing skills using a virtual reality simulator without additional training equaled training using a mechanical simulator.

Computer Simulation↗

PubMed2001

Digital trainer developed for robotic assisted cardiac surgery.

Robotic systems for cardiac surgery have been introduced in clinical trials to facilitate minimally invasive techniques. Widespread use of surgical robotics necessitates new training methods to improve skills and continue practicing as the robotic systems are frequently being upgraded. Today, robotic training is performed on expensive animal models. An integration of a digital trainer with the two present robotic systems applied in coronary artery bypass procedures on beating heart requires real time simulation of tissue mechanics, sutures, instruments and bleeding. However, it requires no extra haptic device, since the robotic master is the haptic apparatus itself. By developing new data structures and parametric geometry descriptions we have demonstrated the possibility of obtaining surgical simulation on a standard PC Linux system. This technology is beneficial when simulation is exploited over a network with limited bandwidth, especially when it comes to the handling of soft tissue dynamics.

Computer Simulation↗

PubMed2000

Controlled auxotonic twitch in papillary muscle: a new computer-based control approach.

Based on new advancements in digital technology, we developed a PC- and DSP-based measurement and control system for isolated papillary muscle experiments. High flexibility was obtained through a three level control. Length or force was controlled real-time with a sample frequency of 5000 Hz. Muscle length and up to three segment lengths were measured simultaneously and each of these lengths could be chosen as feedback variable. Individual algorithms were implemented for different twitch types. Batches of twitches were organized in experiment protocols. The system included a new twitch type, namely a controlled auxotonic twitch. In this twitch, the muscle acted against a virtual ideal spring, giving a proportional change in developed force and shortening. The value of the virtual spring constant could be set on-line or defined in the experiment protocol. An increasing virtual spring constant represented a smooth transition from isotonic to isometric conditions.

Algorithms↗