Abstract #3688

Measurement of Upper Airway Compliance Using Dynamic MRI

Yoon-Chul Kim¹, Ximing Wang², Winston Tran², Michael C.K. Khoo², Krishna S. Nayak¹

¹Electrical Engineering, University of Southern California, Los Angeles, CA, United States; ²Biomedical Engineering, University of Southern California, Los Angeles, CA, United States

In research studies of obstructive sleep apnea, upper airway (UA) compliance (related to the amount of change in UA cross-sectional area per unit pressure) is a measure of airway collapsibility. Fiberoptic endoscopy is used to measure the area but is invasive. We present a new MR imaging protocol that simultaneously acquires dynamic airway images and physiological signals and is compatible with an external airway occlusion setup. UA compliance was measured after synchronization of the UA area and mask pressure dynamics. The measurements in two volunteers during wakefulness suggest that the velopharyngeal site is likely to collapse first over the oropharyngeal site.