Evaluation of the usability of two types of image display systems, during laparoscopy

Abstract
This study was performed to assess the optimal display location of a flat-screen monitor for laparoscopy. It was also performed to assess the posture (objective), opinion, and preference (subjective) of subjects using a flat-screen monitor positioned in the optimal display location and a cathode-ray tube monitor on a tower next to the operating table (current situation). Twelve surgeons performed cholecystectomies using the two display systems alternately. The postures of the operator and the assistant were assessed by an infrared video analysis system. The posture of the assistant is significantly better when using a flat-screen monitor [more neutral head flexions (p = 0.036) and neutral neck torsions (p = 0.012)]. No significant differences were found for the posture of the operator. The operators and assistants felt more comfortable when using a flat-screen monitor (p = 0.008) and they preferred this display to the use of a monitor on a tower. The use of flat-screen monitors is better for the physical and psychological comfort of the users, even though the technical performance is inferior in comparison with that of regular monitors.