Limits...
Surgical simulator design and development.

Dankelman J - World J Surg (2008)

Bottom Line: Several training simulators have become commercially available, but fundamental research into the requirements for effective and efficient training in MIS is still lacking.During MIS, force feedback is reduced owing to friction in the laparoscopic instruments and within the trocar.Although force feedback is reduced during MIS, it is needed for tissue manipulation, and therefore force application should be trained as well.

View Article: PubMed Central - PubMed

Affiliation: Department of BioMechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering (3mE), Delft University of Technology, Mekelweg 2, Delft, 2628, CD, The Netherlands. j.dankelman@tudelft.nl

ABSTRACT
With the introduction of minimally invasive surgery (MIS), it became necessary to develop training methods to learn skills outside the operating room. Several training simulators have become commercially available, but fundamental research into the requirements for effective and efficient training in MIS is still lacking. Three aspects of developing a training program are investigated here: what should be trained, how it should be trained, and how to assess the results of training. In addition, studies are presented that have investigated the role of force feedback in surgical simulators. Training should be adapted to the level of behavior: skill-based, rule-based, or knowledge-based. These levels can be used to design and structure a training program. Extra motivation for training can be created by assessment. During MIS, force feedback is reduced owing to friction in the laparoscopic instruments and within the trocar. The friction characteristics vary largely among instruments and trocars. When force feedback is incorporated into training, it should include the large variation in force feedback properties as well. Training different levels of behavior requires different training methods. Although force feedback is reduced during MIS, it is needed for tissue manipulation, and therefore force application should be trained as well.

Show MeSH
Interposition of instruments between the surgeon’s hands and the tissue. Force feedback is reduced because of friction of the instruments (1, 2) in the trocar (3, 4, 5) and the limited flexibility of the abdominal wall
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2211365&req=5

Fig3: Interposition of instruments between the surgeon’s hands and the tissue. Force feedback is reduced because of friction of the instruments (1, 2) in the trocar (3, 4, 5) and the limited flexibility of the abdominal wall

Mentions: To investigate the role of reduced force feedback during surgery, and therefore also during training, forces must be measured. In our group, a number of studies have been performed to explore the reduction of force feedback in more detail [31]. Force transmission is distorted for several reasons (Fig. 3). Sjoerdsma et al. determined the mechanical transmission characteristics of four different graspers by measuring the ratio between the forces in the jaw and the forces in the handgrip at different opening angles (1 and 2 in Fig. 3). It was found that the mechanical transfer functions were highly nonconstant, differing greatly among the graspers. Furthermore, the transmission function of the grasping forces to the hand was dependent on the opening handle, and the mechanical efficiency was less than 50% [32]. Den Boer et al. [33] evaluated the feedback quality of commercially available reusable and disposable dissectors. Subjects were asked to feel a simulated arterial pulse in a tube, and a sensory threshold measured by a psychophysical method was determined. It was found that the sensory threshold is highly dependent on the mechanical efficiency of the instruments. Heijnsdijk et al. [34] showed that when the mechanical efficiency was improved the performance during tissue-holding tasks was not. Tasks to determine tissue properties, however, were performed better with instruments having a high mechanical efficiency, indicating that the impact of impaired force feedback depends on the task being performed.Fig. 3


Surgical simulator design and development.

Dankelman J - World J Surg (2008)

Interposition of instruments between the surgeon’s hands and the tissue. Force feedback is reduced because of friction of the instruments (1, 2) in the trocar (3, 4, 5) and the limited flexibility of the abdominal wall
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2211365&req=5

Fig3: Interposition of instruments between the surgeon’s hands and the tissue. Force feedback is reduced because of friction of the instruments (1, 2) in the trocar (3, 4, 5) and the limited flexibility of the abdominal wall
Mentions: To investigate the role of reduced force feedback during surgery, and therefore also during training, forces must be measured. In our group, a number of studies have been performed to explore the reduction of force feedback in more detail [31]. Force transmission is distorted for several reasons (Fig. 3). Sjoerdsma et al. determined the mechanical transmission characteristics of four different graspers by measuring the ratio between the forces in the jaw and the forces in the handgrip at different opening angles (1 and 2 in Fig. 3). It was found that the mechanical transfer functions were highly nonconstant, differing greatly among the graspers. Furthermore, the transmission function of the grasping forces to the hand was dependent on the opening handle, and the mechanical efficiency was less than 50% [32]. Den Boer et al. [33] evaluated the feedback quality of commercially available reusable and disposable dissectors. Subjects were asked to feel a simulated arterial pulse in a tube, and a sensory threshold measured by a psychophysical method was determined. It was found that the sensory threshold is highly dependent on the mechanical efficiency of the instruments. Heijnsdijk et al. [34] showed that when the mechanical efficiency was improved the performance during tissue-holding tasks was not. Tasks to determine tissue properties, however, were performed better with instruments having a high mechanical efficiency, indicating that the impact of impaired force feedback depends on the task being performed.Fig. 3

Bottom Line: Several training simulators have become commercially available, but fundamental research into the requirements for effective and efficient training in MIS is still lacking.During MIS, force feedback is reduced owing to friction in the laparoscopic instruments and within the trocar.Although force feedback is reduced during MIS, it is needed for tissue manipulation, and therefore force application should be trained as well.

View Article: PubMed Central - PubMed

Affiliation: Department of BioMechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering (3mE), Delft University of Technology, Mekelweg 2, Delft, 2628, CD, The Netherlands. j.dankelman@tudelft.nl

ABSTRACT
With the introduction of minimally invasive surgery (MIS), it became necessary to develop training methods to learn skills outside the operating room. Several training simulators have become commercially available, but fundamental research into the requirements for effective and efficient training in MIS is still lacking. Three aspects of developing a training program are investigated here: what should be trained, how it should be trained, and how to assess the results of training. In addition, studies are presented that have investigated the role of force feedback in surgical simulators. Training should be adapted to the level of behavior: skill-based, rule-based, or knowledge-based. These levels can be used to design and structure a training program. Extra motivation for training can be created by assessment. During MIS, force feedback is reduced owing to friction in the laparoscopic instruments and within the trocar. The friction characteristics vary largely among instruments and trocars. When force feedback is incorporated into training, it should include the large variation in force feedback properties as well. Training different levels of behavior requires different training methods. Although force feedback is reduced during MIS, it is needed for tissue manipulation, and therefore force application should be trained as well.

Show MeSH