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

A dual-view multi-resolution laparoscope for safer and more efficient minimally invasive surgery

Minimally invasive surgery (MIS) is limited in safety and efficiency by the hand-held nature and narrow fields of view of traditional laparoscopes. A multi-resolution foveated laparoscope (MRFL) was invented to address these concerns. The MRFL is a stationary dual-view imaging device with optical panning and zooming capabilities. It is designed to simultaneously capture and display a zoomed view and supplemental wide view of the surgical field. Optical zooming and panning capabilities facilitate repositioning of the zoomed view without physically moving the system. Additional MRFL features designed to improve safety and efficiency include its snub-nosed endoscope, tool-tip auto tracking, programmable focus profiles, unique selectable display modalities, foot pedal controls, and independently controlled surgeon and assistant displays. An MRFL prototype was constructed to demonstrate and test these features. Testing of the prototype validates its design architecture and confirms the functionality of its features. The current MRFL prototype functions adequately as a proof of concept, but the system features and performance require further improvement to be practical for clinical use.

Surgeon Assessment of a Novel Multi-Resolution Foveated Laparoscope

BACKGROUND

We developed a multi-resolution foveated laparoscope (MRFL) to improve situational awareness in laparoscopic surgery. We assessed surgeon objective task performance and subjective attitudes with MRFL when used for box trainer tasks and porcine surgery.

METHODS

The MRFL simultaneously obtains a wide-angle view and a magnified view. The 2 images are displayed simultaneously. 6 urologists and 2 general surgeons performed box trainer and porcine surgery tasks with the MRFL and a standard laparoscope. Task time, use of display options, and subjective assessments were obtained.

RESULTS

Subjectively, surgeons rated situational awareness, depth perception, and instrument interference as comparable between the prototype MRFL and laparoscope for trainer tasks. For porcine surgery, the MRFL was rated as having less interference than the standard laparoscope. The image quality of the MRFL was rated interior to the standard laparoscope. Participants found the different viewing modes useful for different roles and reported that they would likely use the MRFL for conventional laparoscopic and robotic surgery. Objectively, box trainer task time was comparable for 2 of 3 tasks with the remaining task shorter for the standard laparoscope. Porcine nephrectomy and oophorectomy were feasible with the prototype MRFL, although nephrectomy task time was significantly longer than traditional laparoscopy.

CONCLUSIONS

The MRFL demonstrated feasibility for performing complex surgery. Surgeons had favorable attitudes toward its features and likelihood to use the device if available. Users utilized different view types for different tasks. Longer MRFL task times were attributed to poorer image quality of the prototype.

Further Comparison of 4 Display Modes for a Multi-Resolution Foveated Laparoscope

Background. To overcome field of view and ergonomic limitations of standard laparoscopes, we are developing a multi-resolution foveated laparoscope (MRFL), which can simultaneously obtain both wide- and zoomed-in-view images. To facilitate the effectiveness of our MRFL, we have been investigating various ways of organizing and visualizing dual-view multi-resolution images acquired by the MRFL. In our prior study, we implemented and compared 6 display modes for the MRFL, assuming a typical clinical environment where a standard (but limited) resolution monitor is available. To take full advantage of our MRFL, displays having sufficient screen resolutions might be advantageous. The present study aims to further understand the effects of view configurations through displays with a standard high-definition (HD) resolution and a 4K resolution. In this study, we compare 3 display modes for limited-resolution displays against a new mode for sufficient-resolution displays. Methods. Twenty subjects performed 3 evaluation trials of a touching task with each display mode in an emulated MRFL environment. Various objective measurements including task completion time and the number of collisions, and subjective preference were recorded. Results. The new mode showed a better task completion time than the other modes, while it maintained a low number of collisions similar to the others. Moreover, the majority of participants selected the new mode as their most preferred one. Conclusions. With a sufficient display resolution, the co-registration between the unblocked and unwarped wide context view and the high-resolution zoomed-in view offered by the new mode was highly effective on both task performance and user preference.