Comparison of the upper airway dynamics of oronasal and nasal masks with positive airway pressure treatment using cine magnetic resonance imaging.
OBJECTIVE
It is known that oronasal masks are not as effective at opening the upper airway compared to nasal only continuous positive airway pressure (CPAP) masks in patients with sleep-disordered breathing. However, the physiological mechanism for this difference in efficacy is not known; although, it has been hypothesized to involve the retroglossal and/or retropalatal region of the upper airway. The objective of this study was to investigate differences in retroglossal and retropalatal anterior-posterior space with the use of oronasal vs. nasal CPAP masks using real-time cine magnetic resonance imaging (cMRI).


METHODS
Ten subjects (eight men, two women) with obstructive sleep apnea (OSA) were given cMRI with both nasal and oronasal CPAP masks. Each subject was imaged with each interface at pressures of 5, 10, and 15 cm of H2O, while in the supine position along the sagittal plane.


RESULTS
The oronasal mask produced significantly less airway opening in the retropalatal region of the upper airway compared to the nasal mask interface. During exhalation, mask style had a significant effect on anterior-posterior distance p = 0.016. No differences were found in the retroglossal region between mask styles.


CONCLUSIONS
Our study confirmed previous findings showing differences in treatment efficacy between oronasal and nasal mask styles. We have shown anatomic evidence that the nasal mask is more effective in opening the upper airway compared to the oronasal mask in the retropalatal region.
Department of Neurology, Weill Cornell Medical College, New York, NY, USA. mae2001@med.cornell.edu.|Center for Sleep Medicine, Weill Cornell Medical College, 425 East 61st Street, 5th Floor, New York, NY, 10065, USA. mae2001@med.cornell.edu.
Matthew R
MR
Ebben
Department of Medicine, Weill Cornell Medical College, New York, NY, USA.
Sara
S
Milrad
Department of Radiology, Weill Cornell Medical College, New York, NY, USA.
Jonathan P
JP
Dyke
Department of Radiology, Weill Cornell Medical College, New York, NY, USA.
C Douglas
CD
Phillips
Department of Neurology, Weill Cornell Medical College, New York, NY, USA.|Department of Medicine, Weill Cornell Medical College, New York, NY, USA.
Ana C
AC
Krieger
D000328:Adult; D000368:Aged; D002648:Child; D045422:Continuous Positive Airway Pressure / Q000295:instrumentation*; D004867:Equipment Design; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007223:Infant; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008397:Masks; D008875:Middle Aged; D010159:Palate / Q000503:physiopathology; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology / Q000628:therapy*; D014059:Tongue / Q000503:physiopathology
Apnea; Cine magnetic resonance imaging; Mask; Nasal; Obstructive sleep apnea; Oronasal