Hyoid Suspension as the Only Procedure

1.2

Indications and Contraindications

Obstruction of the airway at the retropalatinal and retropharyngeal airway is the key factor in the pathophysiology of obstructive sleep apnea syndrome (OSAS). Patient selection is crucial in successful surgery of the upper airway in OSAS. In addition to polysomnography, topical diagnostic workup is of paramount importance in this regard. We routinely perform polysomnography first and after that in cases of an Apnea/Hypopnea Index (AHI) below 30, schedule patients for sedated endoscopy (“sleep endoscopy”) with midazolam (without an anesthetist present) in those patients in whom surgery is considered. In patients with an AHI below 30 who refuse nasal continuous positive airway pressure (NCPAP) treatment up front, or in patients who cannot accept NCPAP for whatever reason, sedated endoscopy is performed as well, but by an anesthetist, with propofol. In the study period (March 2000–June 2004), in the case of mainly or only retrolingual obstruction as assessed by sleep endoscopy and a low AHI (arbitrarily <15–20, snoring up to mild sleep apnea), we usually started with radiofrequency ablation of the tongue base. In this situation, in the case of mild or moderate OSAS, oral devices were offered as an alternative. In cases of a relatively higher AHI (moderate to severe OSAS), the effect of Mandibular Repositioning Appliance (MRA) treatment is less efficacious. In the case of an index of 15 to 30 and mainly retrolingual obstruction, we performed hyoid suspension (aka hyoidthyroidpexia ) as the only procedure. In higher AHI patients we perform multilevel surgery (hyoid suspension, radiofrequency ablation of the tongue base, uvulopalatopharyngoplasty [UPPP]), with/or without genioglossal advancement (see Chapter 50 ). These patients usually have more severe and multilevel obstruction, which explains the higher AHI.

Hyoid suspension involves stabilization of the hyoid bone inferiorly by attachment to the superior border of the thyroid cartilage. The underlying principle for altering the hyoid is that anatomically, the hyoid complex is an integral part of the hypopharynx. Anterior movement of the hyoid complex increases the posterior airway space and neutralizes obstruction at the tongue base. This concept has been supported by several reports. In the United States, hyoid suspension is often performed in combination with genioglossus advancement and followed by maxillomandibular osteotomy (MMO) as phased surgery in case of failure. The rationale for using hyoid suspension only in our series was to avoid more radical and more extensive unnecessary surgery in well-selected patients. In this chapter we report our experiences with this procedure.

2.1

Upper Airway Assessment

Hyoid suspension was performed in the case of obstruction at the base of the tongue ( Fig. 53.1 ), assessed by physical examination and flexible sleep endoscopy. A high suspicion of mainly retropalatal obstruction (large tonsils and long uvula) excluded patients for hyoid suspension. Candidates for surgery were categorized into two groups: those who did not have prior surgery at the oropharyngeal or hypopharyngeal level (primary hyoid suspension) and those for whom UPPP was inadequate or detrimental (secondary hyoid suspension). In the latter group hyoid suspension was offered as salvage treatment. Multilevel obstruction (Fujita II) occurred in 20 patients; slight obstruction at the retropalatal level occurred in 9 patients (primary hyoid suspension, n = 14), and residual retropalatal obstruction after UPPP occurred in 12 patients (secondary hyoid suspension, n = 17). Only four patients who underwent primary hyoid suspension showed simple tongue base obstruction (Fujita III). Before UPPP, 15 patients showed multilevel obstruction (Fujita II), with emphasis on the palatal level; 2 patients showed retropalatal obstruction only (Fujita I). Sleep endoscopy workup according to the Fujita classification is shown in Fig. 53.2 .