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Proper monitor height is guided by the gaze-down technique, which is placing the
center of the screen approximately 10–20° below eye level [ 119 ]. This positioning
mimics the neutral orientation of the human eye in its orbit, which is at an inclination
of 15°, and prevents neck extension [ 120 ]. An easy way to approximate proper moni-
tor height is to place the top of the screen at eye level as seen in the top image of
Fig. 22.4 and in Fig. 22.5. In this position, electromyography registers the lowest
Fig. 22.3 Proper monitor placement in the operating room is shown with a straight line between
the surgeon and assistant’s body orientation, target organ, and monitor
C. Ronstrom et al.