Airflow-based detection of lateral wall collapse in sleep apnea patients help predict hypoglossal nerve stimulation efficacy: Study

A new study published in The European Respiratory Journal showed that lateral wall collapse as a major contributing factor to hypoglossal nerve stimulation (HGNS) failure and demonstrates that airflow-based detection of oropharyngeal lateral wall (OLW) collapse may accurately assess HGNS efficacy, marking a substantial improvement in HGNS patient selection.

A significant predictor of how well individuals react to hypoglossal nerve stimulation for obstructive sleep apnea is lateral wall collapse observed during drug-induced sleep endoscopy (DISE). Knowing the pattern of collapse, particularly at the lateral pharyngeal walls, helps determine who will benefit most from HNS since OSA includes dynamic airway constriction.

Also, studies show that airflow shape during sleep provides additional information on neuromuscular tone and airway behavior. Combining these 2 evaluations offers a more precise means of predicting treatment effectiveness, directing patient selection, and maximizing hypoglossal nerve stimulation results.

This study prospectively aimed to establish that OLW collapse is linked to decreased HGNS effectiveness among HGNS candidates. This research also assessed whether a recently developed non-invasive technique for diagnosing OLW collapse using airflow morphologies is linked to decreased HGNS effectiveness since DISE is a resource-intensive process that delays therapy.

This was an observational cohort research that comprised patients who had DISE, HGNS implantation, and follow-up sleep testing. For Aim 2, airflow data predicting the likelihood of OLW collapse were obtained during DISE using a pneumotachograph (n = 138; DISE Flow cohort) and from a home sleep test (HST) using a nasal cannula for validation (n = 46; HST cohort). After controlling for baseline AHI, linear regression quantified relationships between HGNS efficacy (percent decrease in apnoea-hypopnoea index (AHI)) and either DISE-determined OLW collapse or flow shape-determined OLW collapse (probability score per 2sd).

DISE-determined OLW collapse decreased HGNS effectiveness by -18.0% (95% CI -31.9- -6.2%) when compared to non-OLW collapse. In the DISE Flow (-24.8%, 95% CI -40.4- -11.7%) and HST (-22.7%, 95% CI -50.0- -2.6%) cohorts, higher flow shape-determined OLW collapse probability (Δ2sd) was linked to lower HGNS effectiveness.

Overall, oropharyngeal lateral wall collapse decreased the effectiveness of hypoglossal nerve stimulation by −18. Reduced effectiveness in drug-induced sleep endoscopy flow and home sleep test cohorts was predicted by airflow-based OLW probability.

Source:

Vena, D., Op de Beeck, S., Yang, H., Sumner, J., Mann, D., Wang, T.-Y., Aishah, A., Azarbarzin, A., Messineo, L., Calianese, N., Alex, R., Esmaeili, N., Vanderveken, O. M., White, D. P., Wellman, A., Huyett, P., & Sands, S. A. (2025). Lateral wall collapse from sleep endoscopy and airflow shape predicts hypoglossal nerve stimulation efficacy in obstructive sleep apnoea. The European Respiratory Journal: Official Journal of the European Society for Clinical Respiratory Physiology, 66(4), 2500236. https://doi.org/10.1183/13993003.00236-2025