Latency doesn’t negatively affect the performance of most physicians using a three-dimensional heads-up display (3D HUD) visualization systems for vitreoretinal surgery, according to a presentation at the 2020 ASRS Virtual Meeting by David Tri Ta Kim, MD FRCSC. Latency as a key disadvantage of the 3D HUD over the optical microscope should be reevaluated, Dr Kim concluded.
In this study, 30 participants utilized a 3D HUD at 4 levels of latency (50 ms, 66 ms, 90 ms, and 120 ms) to perform suturing and peeling. No statistical difference between completion times between a 50 ms latency and a 122 ms latency were found for either task, regardless of if the participant had VR training or used 3D HUD regularly.
A questionnaire administered for each time trial, found that usability dropped by 60% at 122 ms when compared to 50 ms in the suturing task; no significant difference was noted at 66 ms or 90 ms. Usability dropped 20% at 122 ms compared to 50 ms in the peeling task.
The authors concluded that, “The results of this study suggest that latency, at the levels found in current models of 3D HUD, are below the threshold of negatively affecting performance for the majority of users and therefore challenge the belief that latency plays a key role in the difference felt between the optical microscope and 3D HUD.”
Tri Ta Kim D, et al. The effect of latency on digital vitreoretinal surgery. Presented at: 2020 ASRS Virtual Meeting.