Recognizing hypertrophy of torus tubaris: Implications for pediatric hypoglossal nerve stimulation in down syndrome children

Abstract

Objective

Pediatric hypoglossal nerve stimulation (HGNS) is an effective treatment for severe obstructive sleep apnea (OSA) in children with Down syndrome (DS). However, candidacy for HGNS requires the absence of concentric velopharyngeal collapse on drug-induced sleep endoscopy (DISE). A subset of children with DS with hypertrophic torus tubaris (HTT) may appear to have velopharyngeal collapse, making diagnosis difficult. We propose a method to differentiate HTT and anteroposterior collapse from true circumferential velopharyngeal collapse.

Study design

Retrospective case series from 2016 to 2024.

Setting

Single tertiary centre.

Methods

Four children with DS and severe OSA underwent DISE as part of HGNS evaluation. HTT were noted to cause velopharyngeal narrowing, mimicking concentric collapse. A 120-degrees endoscope was used to visualize the velopharynx revealing the HTT. These cases were reviewed and subsequently approved for HGNS implantation.

Results

All four children (median age 14.5, range 11–17years, all male) went on to have successful and uncomplicated HGNS, with resolution of OSA defined by a ≥50 % reduction in pre-operative obstructive apnea-hypopnea index (OAHI) and a post-operative OAHI <10 events/h. The median reduction in pre-operative OAHI was 85.2 (range 55.6–93.1 %) and the median post-operative OAHI was 3.85 (range 2.9–7.9 events/h).

Conclusion

Accurate DISE evaluation is crucial to avoid misdiagnosing HTT with anteroposterior velopharyngeal collapse as concentric velopharyngeal collapse, ensuring appropriate HGNS candidacy for children with DS and OSA, who often fail conventional treatments.