Three-dimensional (3-D) video systems: Bi-channel or single-channel optics?

Background and Study Aims: This paper presents the results of a comparison between two different three-dimensional (3-D) video systems, one with singl e-channel optics, the other with hi-channel optics. The latter integrates t wo lens systems, each transferring one half of the stereoscopic image; the former uses only one lens system, similar to a two-dimensional (2-D) endosc ope, which transfers the complete stereoscopic picture. Material and Methods: In our training centre for minimally invasive surgery , surgeons were involved in basic and advanced laparoscopic courses using b oth a 2-D system and the two 3-D video systems. They completed analog scale questionnaires in order to record a subjective impression of the relative convenience of operating in 2-D and 3-D vision, and to identify perceived d eficiencies in the 3-D system. As an objective test, different experimental tasks were developed, in order to measure performance times and to count p re-defined errors made while using the two 3-D video systems and the 2-D sy stem. Results and Conclusions: Using the hi-channel optical system, the surgeon h as a heightened spatial perception, and can work faster and more safely tha n with a single-channel system. However, single-channel optics allow the us e of an angulated endoscope, and the free rotation of the optics relative t o the camera, which is necessary for some operative applications.