Comparison of six display modes for a multi-resolution foveated laparoscope

To overcome the field of view and ergonomic limitations of standard laparoscopes, we are developing a multi-resolution foveated laparoscope that can simultaneously obtain both wide- and zoomed-in-view images through a single scope. To facilitate the effective access to the dual views of images with different resolution and field coverage acquired by our laparoscope, six different display modes have been developed. Each of the six display modes has inherent advantages and disadvantages. This study compares the six display modes through a human-subject experiment, which was conducted with an emulated laparoscope using a 4K camera.

Twenty-four subjects without medicine background performed three evaluation trials of a touching task with each of the display modes. Various objective measurements including task completion time, the number of collisions, gaze position, and tooltip position, and subjective preference for the display modes were recorded.

For all the measurements except for task completion time and moving speed of tooltip, there were statistically significant differences among the display modes. Although the focus plus warped context view mode was selected as one of the least preferred modes, it showed the best task performance.

The unblocked wide context view was useful to provide a situational awareness even when it was severely distorted in some of the display modes, and information continuity played an important role in improving task performance. Moreover, the position change of viewing window coupled to the location of region of interest helped improve task performance, by providing an additional cue for spatial awareness.