Depth Perception in Telemedical Consultations

This study aimed at quantifying diminished depth perception in telemedicine due to the two-dimensional image and to devise coping strategies for the problem. Two hundred and thirty-five patients in the telemedicine room of a Minor Accident and Treatment Service were studied. The magnitude of impaired depth perception was noted. Seven coping strategies were used and the resolution of the problem was measured. Depth perception was judged to be less than 90% of binocular vision in 235 cases. This improved to more than 90% of binocular vision in 99 of the 234 cases (42.13%) when using of all strategies. Improvement by rotation of the camera 30° at a time in the axial plane was the most useful strategy and it occurred in all 235 (100%) cases. Light adjustment and angulation occurred in 206 of 235 cases (87.66%). Comparison with the opposite side helped in 179 of 235 cases (76.17%), skin color and texture in 139 of 235 cases (59.15%), shutting one eye in 103 of 235 cases (43.83%), enlarging the image in 85 of 235 cases (36.17%), and diminishing depth of field of lens in 77 of 235 cases (32.77%). Other visual cues occurred in 63 of 235 cases (26.81%). Impaired depth perception is a significant problem in telemedicine. It can be improved to make a confident diagnosis in most cases by adopting a variety of strategies that are described in this paper.