The influence of stereoscopic vision on surgical performance in minimal invasive surgery-a substudy of the IDOSP-Study (Influence of 3D- vs. 4 K-Display Systems on Surgical Performance in minimal invasive surgery)

Abstract

Purpose: This study is a secondary analysis of the IDOSP trial published in the Annals of Surgery 2020. The aim of this study was to examine the influence of stereo acuity on surgical performance in a laparoscopic training parkour with 3D- versus 4 K-2D-display technique.

Methods: The surgical performance of medical students (MS), non-board-certified surgeons (NBC), and board-certified surgeons (BC) was compared using 3D- versus 4 K-2D-display technique at a training parkour in a randomized cross-over trial. Stereo acuity was tested by TNO and Titmus Stereo tests.

Results: Eighty-nine participants were included in this sub-trial. The median stereo acuity for all participants, measured with the Titmus test, was 25 s arc, with TNO test 30 s arc. Higher quality stereo vision, measured with the Titmus test, correlated significantly with a reduced parkour time (r = 0.26, p = 0.02) and error (r = 0.21, p = 0.048) with the 3D screen. The TNO test did not correlate significantly with parkour performance. There was no statistically significant correlation between parkour time nor error and stereo acuity using the 4 K system (p > 0.457 respectively). Higher age showed a significant correlation with lower stereo acuity measured with TNO (r = 0.21, p = 0.014), but not with the Titmus test (r = - 0.7, p = 0.39). Seven percent of the group "NBC and BC" showed reduced stereo acuity > 120 s arc with the Titmus test and 3% with the TNO test.

Conclusion: High-quality stereo vision is of utmost importance for surgical skills using a 3D-display system. This was most obvious for MS and for tasks that place particularly high demands on hand-eye coordination. The Titmus test was more precise than the TNO test to predict the benefit of a 3D monitor system. Experience and fine motor skills could partly compensate for a poorer stereo acuity.

Trial registration: This trial was registered at clinicaltrials.gov (trial number: NCT03445429, registered February 26, 2018).

Keywords: 3D; 4 K; Laparoscopic; Minimal invasive surgery; Stereo vision; Surgical performance.

Conflict of interest statement

The authors declare no competing interests.

© 2022. The Author(s).

Figures

Fig. 1

Scatter plots showing the correlation between stereo acuity measured by the Titmus or TNO test with parkour time and error

Fig. 2

Boxplots of 4 K-2D (blue) versus 3D (green) median overall parkour time and error for three Titmus and for three TNO stereo subgroups: subgroup 1 with 25 s arc or better, subgroup 2 with > 25 to 40 s arc, and subgroup 3 with 50 s arc and worse

Fig. 3

A The TNO stereo test uses a random dot pattern and requires anaglyph red and green glasses (worn over prescription glasses). The test contains several plates with concealed test items (disks with a sector missing) that only can be seen with binocular vision. Plates V–VII were used for the determination of stereoscopic sensitivity. Measure disparity values were 480, 240, 120, 60, 30, and 15 s of arc. B The Titmus stereo test is a contour stereo test; images are separated horizontally in order to present figures to each eye. This test requires cross-polarized filters (worn over prescription glasses). The second part of the test (circles) was used for the determination of stereoscopic vision. Subjects with stereo vision can see one out of four circles per object coming forward. Measure disparity values were 400, 200, 160, 100, 63, 50, 40, 32, 25, and 20 s of arc