For more than 40 years, surgical procedures were described for the treatment of sleep-related breathing disorders (SRBD) [43, 44, 49]. The physiological spectrum of these diseases ranges from partial upper-airway collapse with an increase in upper-airway resistance, manifested as snoring, flow limitation, and hypopnea, to complete upper-airway collapse and apnea. The soft palate is assumed to be the primary noise generator during sleep, although other structures in the upper airway may generate obstruction to airflow and subsequently hypopnea–apnea. The collapsibility of the upper airway was demonstrated to be different in healthy patients (low), snorers (intermediate), and patients with apnea (high).