Transverse Maxillary Deficiency Predicts Increased Upper Airway Collapsibility during Drug‐Induced Sleep Endoscopy

Abstract

Objective. To examine the relationship between craniofacial skeletal anatomy and objective measures of pharyngeal collapse obtained during drug-induced sleep endoscopy. We hypothesized that transverse maxillary deficiency and an increased pharyngeal length will be associated with higher levels of pharyngeal collapsibility.Study Design. Cross-sectional analysis in a prospective cohort.Setting. University Hospital.Methods. A cross-sectional analysis was conducted in a cohort of consecutive patients from the positive airway pressure (PAP) alternatives clinic who underwent computed tomography (CT) analysis and drug-induced sleep endoscopy for characterization of upper airway collapsibility. PAP titration was used to determine pharyngeal critical pressure (P CRIT ) and pharyngeal opening pressure (PhOP). CT metrics included: Transverse maxillary dimensions (interpremolar and intermolar distances) and pharyngeal length (posterior nasal spine to hyoid distance).Results. The cohort (n = 103) of severe obstructive sleep apnea (Apnea and Hipopnea Index 32.1 ± 21.3 events/h) was predominantly male (71.8%), Caucasian (81.6%), middleaged (54.4 ± 14.3 years), and obese (body mass index [BMI] = 30.0 ± 4.9 kg/m 2 ). Reduced transverse maxillary dimensions were associated with higher P CRIT (intermolar distance: β [95% confidence interval, CI] = −.25 [−0.14, −0.36] cmH 2 O/mm; p = .03) and PhOP (Interpremolar distance: β = −.25 [−0.14, −0.36] cmH 2 O/ mm; p = .02). Longer pharyngeal length was also associated with higher P CRIT (β = .11 [0.08, 0.14] cmH 2 O/mm, p = .04) and PhOP (β [95% CI] = .06 [0.03, 0.09] cmH 2 O/mm, p = .04). These associations persisted after adjustments for sex, age, height, and BMI. Conclusion.Our results further the concept that skeletal restriction in the transverse dimension and hyoid descent are associated with elevations in pharyngeal collapsibility during sleep, suggesting a role of transverse deficiency in the pathogenesis of airway obstruction.

Association Between Soft Tissue Measures From Computed Tomography and Upper Airway Collapsibility on Drug‐Induced Sleep Endoscopy

“…In our investigation, we studied OSA patients (AHI > 5 events/h) undergoing CT and drug‐induced sleep endoscopy with PAP as part of a diagnostic workup for CPAP alternative treatments. In a similar cohort, we have shown that linear CT skeletal measurements, specifically reduced airway width (transverse maxillary dimension) and increased airway length (posterior nasal spine to hyoid distance), were associated with greater collapsibility measures (PhOP and Pcrit A ) after adjustment for age, sex, and BMI 27 . The present study applied a standardized protocol for volumetric analysis to explore soft tissue determinants of upper airway collapsibility.…”

“…In a similar cohort, we have shown that linear CT skeletal measurements, specifically reduced airway width (transverse maxillary dimension) and increased airway length (posterior nasal spine to hyoid distance), were associated with greater collapsibility measures (PhOP and Pcrit A ) after adjustment for age, sex, and BMI. 27 The present study applied a standardized protocol for volumetric analysis to explore soft tissue determinants of upper airway collapsibility. Our results conveyed an association of larger tongue volumes, smaller mandibular volumes, and smaller retro-palatal CSA with greater collapsibility (PhOP).…”

“…Regardless work from our group suggesting that craniofacial transverse deficiency and pharyngeal length can predict increased upper airway collapsibility, 27 yet the impact of soft tissue volumes on pharyngeal collapsibility requires more investigation. 28 The present study seeks to determine whether soft tissue measurements from awake CT are associated with the severity of upper airway collapse observed during DISE-PAP.…”