Clinical Radiographic Predictors of Response to Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea

• Authors: Clara H Lee, Weill Cornell Med Coll; Everett G Seay, University of Pennsylvania; James W Reese, Baylor Radiologists; Xin Wu, Emory University; Richard J Schwab, University of Pennsylvania; Brendan Keenan, University of Pennsylvania; Raj C Dedhia, University of Pennsylvania
• Journal Title: OTOLARYNGOLOGY-HEAD AND NECK SURGERY
• Volume: Volume 164, Number 5
• Publisher: SAGE PUBLICATIONS LTD | 2021-05-01, Pages 1122-1127
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1177/0194599820963141
• Subjects: Health Sciences, Radiology; Health Sciences, Medicine and Surgery
• Keywords: Science & Technology; Life Sciences & Biomedicine; Otorhinolaryngology; Surgery; obstructive sleep apnea; hypoglossal nerve stimulation; radiograph; outcomes; POSITIVE AIRWAY PRESSURE; THERAPY

Abstract

Objective: To determine if clinically acquired cephalometric measurements, specifically soft palate size, can predict hypoglossal nerve stimulation outcomes. Study Design: Combined prospective cohort study and retrospective review. Setting: US sleep otolaryngology training program. Methods: Adults with obstructive sleep apnea and apneahypopnea index greater than 15 events/h who underwent hypoglossal nerve stimulation. Eligible subjects had diagnostic preoperative sleep studies and full-night efficacy postoperative studies for analysis. Lateral neck x-rays were obtained as part of routine clinical care and measured for key cephalometric variables by trained head and neck radiologists. Continuous variables were compared using the Student t test, while χ2 testing was used for categorical variables. Results: Fifty-one patients met all study criteria. On average, patients were white, middle aged, and overweight. Following hypoglossal nerve stimulation, the overall cohort achieved a significant apnea-hypopnea index reduction from 36.7 events/h to 20.6 events/h (P <.01) and a response rate of 47% (defined as apnea-hypopnea index reduction >50% and apnea-hypopnea index <20 events/h). On average, therapy responders had significantly thinner soft palates than nonresponders (13.4 ± 3.8 mm vs 16.0 ± 3.4 mm, P =.045). Conclusions: Patient-specific anatomic factors, specifically soft palate thickness, may help identify optimal candidates for hypoglossal nerve stimulation. A larger, prospective study including both anatomic and physiologic variables is required to validate these findings.