HNS therapy is intended for adults with moderate to severe
obstructive sleep apnea who meet specific medical criteria. Candidates typically have an
apnea–hypopnea index (AHI) between about 15 and 65 events per hour, indicating moderate or severe
OSA. Patients should first have attempted
CPAP therapy, and either failed to achieve adequate results or been unable to tolerate
CPAP use. In clinical practice and trials, patients with a BMI above roughly 32 kg/m^2 were significantly less likely to respond to the treatment. Other key selection factors include ensuring the OSA is predominantly obstructive (with
central or mixed sleep apnea events accounting for less than 25% of the total AHI). The purpose of DISE is to confirm that the pattern of airway collapse is one that HNS can alleviate. In particular, the patient must not have a complete concentric collapse at the level of the soft palate, because simply moving the tongue forward would not resolve an all-around collapse of the airway at that location. Patients with very large tonsils that could physically prevent the device from working are also excluded until those issues are addressed. In summary, HNS is generally indicated for adult OSA patients meet the following criteria: • Moderate-to-severe OSA (AHI in approximately the 15–65 range) with mainly obstructive events. • An inability to use CPAP successfully (due to lack of efficacy or intolerance). •
Polysomnography conducted within 24 months prior to the initial consult for HNS implantation. • A body mass index below 32-35 kg/m^2. • Favorable airway anatomy, confirmed by drug-induced sleep endoscopy, without a complete concentric collapse at the
soft palate. • No other anatomical findings that would compromise performance of device. == Procedure details ==