Endoscopic camera rotation: a conceptual solution to improve hand-eye coordination in minimally-invasive surgery

During minimally-invasive surgery the surgeon's hand-eye coordination is di sturbed due to indirect sight of the operative field. Two negative effects occur: the location and the orientation of the operative field presented on the monitor do not correspond to the location and orientation of the actua l operative field. This study investigated whether endoscopic task performa nce improves under the following conditions: with location of the monitor s creen at surgeon's hand level, and with rotation of the endoscopic camera s o that the instrument movements in the monitor image are no longer misorien ted with respect to the actual instrument movements. An endoscopic manipula tion task was performed under standardised conditions, except for two varyi ng monitor and camera rotations. The endoscope was positioned so that a 90 degrees misorientation between the displayed instrument and actual instrume nt existed in the standard condition. Task performance was best when the en doscopic camera was rotated, so that misorientations between the movements of the displayed instrument and the actual instrument were eliminated. The execution time was shorter (p <0.05) and the experienced mental effort was lower (p <0.01). Monitor location did not significantly influence overall t ask performance. Rotation of the endoscopic camera, so that misorientations are eliminated, improves eye-hand coordination during endoscopic manipulat ion.