Fig. 3From: Quantitative effects of head rotation angle on apnea hypopnea index in positional obstructive sleep apnea – a preliminary case seriesMean apnea-hypopnea index (AHI) at all head rotation angles (A), head rotation ≤ 20° vs > 20° from horizon (B), torso position supine vs non-supine (C), and combination of head rotation angle and torso position (D)Back to article page